KR20170125080A - Liquid crystal aligning agent, liquid crystal alignment film and liquid crystal display element - Google Patents

Abstract

하기 (A) 성분, (B) 성분을 함유하는 액정 배향제.
(A) 성분 : 액정을 수직 배향시키는 측사슬과, 라디칼 발생 부위를 갖는 측사슬을 갖는 폴리이미드 전구체 및 그것을 이미드화하여 얻어지는 폴리이미드에서 선택되는 적어도 1 종의 중합체.
(B) 성분 : 하기에서 선택되는 적어도 1 종의 디아민을 사용하여 얻어지는 폴리이미드 전구체 및 그것을 이미드화하여 얻는 폴리이미드에서 선택되는 중합체, 또는 하기에서 선택되는 적어도 1 종의 테트라카르복실산 2 무수물을 사용하여 얻어지는 폴리이미드 전구체 및 그것을 이미드화하여 얻는 폴리이미드에서 선택되는 중합체.
식 중의 기호의 정의는 명세서 기재와 같다.

A liquid crystal aligning agent containing the following components (A) and (B).
Component (A): at least one polymer selected from a polyimide precursor having side chains for vertically aligning liquid crystals and side chains having radical generating sites, and polyimide obtained by imidating the side chains.
Component (B): a polymer selected from a polyimide precursor obtained by using at least one diamine selected from the following and a polyimide obtained by imidating it, or a tetracarboxylic acid dianhydride selected from the following And a polymer selected from a polyimide obtained by imidizing the polyimide precursor.
The definitions of the symbols in the formula are the same as those in the specification.

Description

TECHNICAL FIELD [0001] The present invention relates to a liquid crystal alignment film, a liquid crystal alignment film, a liquid crystal alignment film,

The present invention relates to a liquid crystal aligning agent, a liquid crystal alignment film, and a liquid crystal display element which can be used for a liquid crystal display element of a vertical alignment type manufactured by irradiating ultraviolet rays while applying a voltage to liquid crystal molecules.

A liquid crystal display element of a method of responding liquid crystal molecules oriented perpendicularly to a substrate by an electric field (also referred to as a vertical alignment (VA) system) includes a step of irradiating ultraviolet rays while applying a voltage to the liquid crystal molecules .

In such a vertical alignment type liquid crystal display device, ultraviolet rays are irradiated while a voltage is applied to the liquid crystal cell and a photo-polymerizable compound is added to the liquid crystal composition in advance and a vertical alignment film such as a polyimide system is used. (PSA (Polymer Sustained Alignment) type device, for example, see Patent Document 1 and Non-Patent Document 1).

In such a PSA type device, the direction in which the liquid crystal molecules in response to an electric field is generally tilted is controlled by protrusions formed on the substrate or slits formed on the display electrodes, etc. However, a photopolymerizable compound is added to the liquid crystal composition, Since the polymer structure in which the direction in which the liquid crystal molecules are tilted is formed on the liquid crystal alignment film by irradiating ultraviolet rays while applying a voltage, compared with the method of controlling the tilt direction of the liquid crystal molecules only by the projections or slits, It is said to be speeding up.

On the other hand, in this PSA type liquid crystal display element, the unreacted polymerizable compound remaining in the liquid crystal becomes an impurity (contamination) in the liquid crystal, and thus there is a problem that the reliability of the liquid crystal display element is lowered. Further, in the UV irradiation treatment required for the PSA method, if the irradiation amount is large, the components in the liquid crystal are decomposed to cause a decrease in reliability.

It has also been reported that the response speed of a liquid crystal display element is also increased by adding a photopolymerizable compound to a liquid crystal alignment film instead of a liquid crystal composition (SC-PVA type liquid crystal display, see, for example, Non-Patent Document 2) .

Japanese Patent Application Laid-Open No. 2003-307720

 K. Hanaoka, SID 04 DIGEST, pp. 1200-1202  K. H. Y.-J. Lee, SID 09 DIGEST, P.666-668

In recent years, with the improvement of the quality of a liquid crystal display element, it is desired to further accelerate the response speed of the liquid crystal with respect to voltage application. For this purpose, it is necessary that the polymerizable compound reacts effectively with irradiation of ultraviolet light having a long wavelength not accompanied by decomposition of components in the liquid crystal, thereby exhibiting the orientation fixation ability. In addition, unreacted polymerizable compounds do not remain after irradiation with ultraviolet rays, so that the reliability of the liquid crystal display element may not be adversely affected.

It is also desired to improve the electric characteristics of the resulting liquid crystal display element, in particular to improve the DC charge storage characteristics.

The object of the present invention is to solve the problems of the above-described conventional techniques, and it is also possible to efficiently react the polymerizable compound with ultraviolet rays of a long wavelength, to improve the response speed of the liquid crystal display element of the vertical alignment system, A liquid crystal alignment film, a liquid crystal display element and a method of manufacturing a liquid crystal display element which can improve the electric characteristics of the obtained liquid crystal display element, in particular, the direct current charge accumulation characteristics.

As a result of intensive studies, the inventors of the present invention have found that the above problems can be achieved by introducing a specific structure that generates radicals by irradiation with ultraviolet light to a polymer constituting the liquid crystal aligning agent, thereby completing the present invention.

That is, the present invention has the following points.

1. A liquid crystal aligning agent comprising the following components (A), (B) and an organic solvent.

(A): a polyimide precursor having side chains for vertically orienting liquid crystals and side chains having sites for generating radicals by irradiation with ultraviolet rays represented by the following formula (I), and polyimide precursors At least one kind of polymer selected from the polyimide obtained.

[Chemical Formula 1]

R ₁ and R ₂ each independently represent an alkyl group or an alkoxy group having 1 to 10 carbon atoms; T ₁ and T ₂ each independently represents a single bond or a group selected from the group consisting of -O-, -COO-, -OCO-, -NHCO-, _{-CONH-, -NH-, -CH 2 O-,} -N (CH 3) -, -CON (CH 3) -, -N (CH 3) and the coupler of the CO-, S is a single bond or unsubstituted or An alkylene group having 1 to 20 carbon atoms which is substituted by a fluorine atom. The -CH ₂ - or -CF ₂ - of the mono-alkylene group may be optionally substituted with -CH = CH-, and in the case where any of the groups shown below are not adjacent to each other, these groups may be substituted; -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbon ring, a divalent heterocyclic ring, and Q represents a structure selected from the following.

(2)

And R is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

(B): a polyimide precursor obtained by using as a raw material a diamine component containing at least one diamine selected from the following formulas (B-1) to (B-5), and a polyimide precursor obtained by imidizing the polyimide precursor A polyimide precursor obtained by using as a raw material a tetracarboxylic acid dianhydride component containing a polymer selected from polyimide or at least one tetracarboxylic acid dianhydride selected from the following formulas (3) and (4), and A polymer selected from polyimides obtained by imidizing the polyimide precursor.

(3)

Y ₁ is a monovalent organic group having a secondary amine, a tertiary amine or a heterocyclic structure, and Y ₂ is a divalent organic group having a secondary amine, a tertiary amine or a heterocyclic structure.

[Chemical Formula 4]

n, m is 0 or 1, and X and y are a single bond, a carbonyl, an ester, a phenylene, or a sulfonyl group.

2. A liquid crystal alignment film obtained by coating the substrate with the liquid crystal aligning agent and firing the liquid crystal aligning agent.

3. The liquid crystal display according to claim 1, wherein the liquid crystal cell is provided by irradiating ultraviolet rays while applying a voltage to the liquid crystal layer in contact with a liquid crystal alignment film obtained by applying and firing the liquid crystal aligning agent described in 3.1. device.

A liquid crystal cell is produced by irradiating ultraviolet rays while applying a voltage to the liquid crystal layer by contacting the liquid crystal alignment film obtained by applying and firing the liquid crystal aligning agent described in 4.1 to the substrate to form a liquid crystal cell / RTI >

According to the present invention, it is possible to provide a liquid crystal display element of the vertical alignment system which can accelerate the response speed of the liquid crystal even with a long wavelength ultraviolet light irradiation and has less accumulation of direct current charges.

The liquid crystal aligning agent of the present invention contains the following components (A), (B) and an organic solvent.

(A): a polyimide precursor having side chains for vertically orienting liquid crystals and side chains having sites for generating radicals by irradiation with ultraviolet rays represented by the following formula (I), and polyimide precursors At least one kind of polymer selected from the polyimide obtained.

[Chemical Formula 5]

(B): a polyimide precursor obtained by using at least one kind of diamine selected from the following formulas (B-1) to (B-5) as a raw material and a polyimide obtained by imidizing the polyimide precursor A polymer selected from a polyimide precursor obtained by using a polymer or at least one tetracarboxylic acid dianhydride selected from the following formulas (3) and (4) as raw materials, and a polyimide obtained by imidizing the polyimide precursor .

[Chemical Formula 6]

(7)

The liquid crystal alignment film is a solution for forming a liquid crystal alignment film, and the liquid crystal alignment film is a film for aligning the liquid crystal in a predetermined direction.

Hereinafter, each constituent requirement will be described in detail.

≪ Component (A) >

The liquid crystal aligning agent of the present invention comprises a side chain for vertically orienting a liquid crystal and a polyimide precursor having a side chain having a site generating a radical by ultraviolet irradiation represented by the formula (1), and a polyimide precursor Is at least one kind of polymer selected from polyimides obtained by imidization.

Here, the polyimide precursor refers to polyamic acid and polyamic acid ester.

≪ Side chain in which radicals are generated by ultraviolet irradiation >

The component (A) contained in the liquid crystal aligning agent of the present invention has, as a side chain, a site where radicals are generated by ultraviolet irradiation. A site where radicals are generated by ultraviolet irradiation can be represented by the following formula (I).

[Chemical Formula 8]

In the formula (I), Ar bonded to the carbonyl is involved in the absorption wavelength of ultraviolet rays, and therefore, a structure having a long conjugate length such as naphthylene or biphenylene is preferable when the wavelength is long. Ar may be substituted with a substituent, and such substituent is preferably an electron-donating organic group such as an alkyl group, a hydroxyl group, an alkoxy group, an amino group or the like.

When Ar has a structure such as naphthylene or biphenylene, the solubility is deteriorated and the degree of difficulty of synthesis is also increased. If the wavelength of the ultraviolet ray is in the range of 250 nm to 380 nm, a phenyl group is most preferable since sufficient characteristics can be obtained even with a phenyl group.

R ₁ and R ₂ are each independently an alkyl group, an alkoxy group, a benzyl group or a phenethyl group having 1 to 10 carbon atoms, and in the case of an alkyl group or an alkoxy group, R ₁ and R ₂ may form a ring .

Q is preferably an electron-donating organic group, and is preferably the following.

[Chemical Formula 9]

(R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ₃ represents -CH ₂ -, -NR-, -O-, or -S-.)

When Q is represented by -OR, R is preferably an alkyl group having 1 to 4 carbon atoms for the purpose of increasing the surface presence ratio of the component (A) after coating. When Q is alkyl, the polarity is lowered and it is easy to shift to the surface. From the viewpoint of the difficulty of synthesis and the like, 1 to 2 is more preferable, and 1 is most preferable.

In the case where Q is an amino derivative, there is a possibility that a problem such as formation of a salt with a carboxylic acid group and an amino group may occur during polymerization of polyamic acid which is a precursor of polyimide, and therefore, Practical skill.

When a polyimide precursor and / or a polyimide is used as the polymer containing the liquid crystal aligning agent and the structure of the formula (I) is to be introduced into the side chain, the side chain structure of the formula (I) It is preferable in view of handleability and ease of synthesis of the polymer.

Concretely, the following are preferably the moieties which generate radicals by ultraviolet irradiation in the formula (I). Particularly, (b), (c), or (d) is preferable in view of the reliability of the resulting liquid crystal display element, and more preferably (d) in terms of the surface layer existence ratio of the radical generating site on the surface of the liquid crystal alignment film.

[Chemical formula 10]

In addition, -T ₁ -ST ₂ - serves as a linking group connecting diaminobenzene and a site which generates a radical by ultraviolet irradiation. T ₁ and T ₂ are each independently a single bond, -O-, -S-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N (CH ₃ ) -, -CON (CH ₃ ) -, or -N (CH ₃ ) CO-. S is an alkylene group having 1 to 20 carbon atoms which may be substituted by a single bond or a fluorine atom (provided that -CH ₂ - or -CF ₂ - in the alkylene group may be optionally substituted with -CH = CH- , -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbon ring or a heterocyclic ring, provided that any of the following groups is not adjacent to each other, to be. In particular, T ₂ is most preferably -O- in terms of the degree of synthetic difficulty. S is preferably an alkylene group having 2 to 10 carbon atoms, more preferably 4 to 8 carbon atoms in view of the degree of synthesis and solubility.

<Side Chain for Vertically Orienting Liquid Crystal>

The polymer contained in the liquid crystal aligning agent of the present invention preferably has, in addition to the side chain represented by the formula (I), a side chain that vertically aligns the liquid crystal. The side chain for vertically orienting the liquid crystal is represented by the following formula [II-1] or formula [II-2].

(11)

X ¹ , X ² , X ³ , X ⁴ , X ⁵ , and n in the formula [II-1] are as defined above.

Among them, X ¹ is preferably a single bond, - (CH ₂ ) _a - (a is an integer of 1 to 15), -O-, -CH ₂ O-, or -O- in view of availability of raw materials and ease of synthesis. -COO-, more preferably a single bond, - (CH ₂ ) _a - (a is an integer of 1 to 10), -O-, -CH ₂ O- or -COO-. Among them, X ² is preferably a single bond or (CH ₂ ) _b - (b is an integer of 1 to 10). X ³ is preferably a single bond, - (CH ₂ ) _c - (c is an integer of 1 to 15), -O-, -CH ₂ O- or -COO- in view of ease of synthesis , More preferably a single bond, - (CH ₂ ) _c - (c is an integer of 1 to 10), -O-, -CH ₂ O- or -COO-.

Among them, X ⁴ is preferably an organic group having from 17 to 51 carbon atoms having a benzene ring, a cyclohexane ring or a steroid skeleton from the viewpoint of ease of synthesis. X ⁵ is preferably a benzene ring or a cyclohexane ring. n is preferably from 0 to 3, more preferably from 0 to 2, from the viewpoint of availability of raw materials and ease of synthesis.

X ⁶ is preferably an alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 10 carbon atoms, an alkoxyl group having 1 to 18 carbon atoms, or a fluorinated alkoxyl group having 1 to 10 carbon atoms. More preferably an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms. And particularly preferably an alkyl group having 1 to 9 carbon atoms or an alkoxyl group having 1 to 9 carbon atoms.

Preferable combinations of X ¹ , X ² , X ³ , X ⁴ , X ⁵ , X ⁶ and n in the formula [II-1] include those described in International Publication No. WO2011 / 132751 (2-1) to (2-629) listed in Tables 6 to 47 on pages 34 to 34 can be used. In each table of the International Publication, X ¹ to X ⁶ in the present invention are represented as Y ¹ to Y ⁶ , and Y ¹ to Y ⁶ are read in place of X ¹ to X ⁶ .

In (2-605) to (2-629) listed in the tables of International Publication, the organic group having a steroid skeleton having 17 to 51 carbon atoms in the present invention is a group having a carbon number of 12 to 25 The organic group having 12 to 25 carbon atoms having a steroid skeleton is replaced with an organic group having 17 to 51 carbon atoms having a steroid skeleton. Among them, (2-25) to (2-96), (2-145) to (2-168), (2-217) to (2-240), (2-268) , (2-364) to (2-387), (2-436) to (2-483), or (2-603) to (2-615). Particularly preferable combinations are (2-49) to (2-96), (2-145) to (2-168), (2-217) to (2-240), (2-603) 606), (2-607) to (2-609), (2-611), (2-612), or (2-624).

[Chemical Formula 12]

In the formula [II-2], X ⁷ and X ⁸ are as defined above. X ⁷ is preferably a single bond, -O-, -CH ₂ O-, -CONH-, -CON (CH ₃ ) - or -COO-, more preferably a single bond, -O-, CONH- or -COO-. X ⁸ Among them, an alkyl group having 8 to 18 carbon atoms is preferable.

As the side chain for vertically orienting the liquid crystal, it is preferable to use the structure represented by the formula [II-1] from the viewpoint of obtaining a high and stable vertical orientation of the liquid crystal.

The ability of a polymer having a side chain to vertically orient liquid crystals to vertically orient liquid crystals differs depending on the structure of side chains vertically orienting liquid crystals, but generally the amount of side chains that vertically orient liquid crystals The ability to vertically orient the liquid crystal increases, and when it is decreased, it decreases. Further, in the case of having a cyclic structure, the ability of vertically aligning the liquid crystal tends to be higher as compared with the case where the cyclic structure is not provided.

&Lt; Side chain of photoreactive &

The component (A) contained in the liquid crystal aligning agent of the present invention may have a photoreactive side chain in addition to the side chain represented by the above formula (I). The photoreactive side chain has a functional group capable of forming a covalent bond (hereinafter also referred to as a photoreactive group) by reaction with light such as ultraviolet (UV) light.

The photoreactive side chain may be directly bonded to the main chain of the polymer or may be bonded via a bonding group. The side chain of the photoreactive is represented by, for example, the following formula (III).

[Chemical Formula 13]

In the formula (III), R ⁸ , R ⁹ and R ¹⁰ are as defined above. Among them, R ⁸ is preferably a single bond, -O-, -COO-, -NHCO-, or -CONH-. R ⁹ can be formed by a conventional organic synthetic method, but from the viewpoint of ease of synthesis, a single bond or an alkylene group having 1 to 12 carbon atoms is preferable.

Specific examples of the divalent carbon ring or heterocyclic ring for substituting any -CH ₂ - in R ⁹ include the following.

[Chemical Formula 14]

R ¹⁰ is preferably a methacryl group, an acrylic group, a vinyl group or a styryl group in view of photoreactivity.

The existing amount of the photoreactive side chain is preferably within a range capable of accelerating the response speed of the liquid crystal by reacting with ultraviolet light to form a covalent bond and in order to accelerate the response speed of the liquid crystal, Insofar as no influence is given, as much as possible is preferable.

<Specific diamine>

The diamine (hereinafter also referred to as a specific diamine) used in the production of the polymer forming the liquid crystal aligning agent of the present invention has, as a side chain, a site where a radical is decomposed by irradiation with ultraviolet rays.

[Chemical Formula 15]

Ar, R ₁ , R ₂ , T ₁ , T ₂ , and Sn in the above formula (1) are as defined above.

The diaminobenzene in the formula (1) may have any structure of o-phenylenediamine, m-phenylenediamine or p-phenylenediamine, but from the viewpoint of reactivity with acid dianhydrides, m-phenylenediamine , Or p-phenylenediamine is preferable.

The specific diamine is most preferably a structure represented by the following formula in view of ease of synthesis, high versatility, and characteristics. In the formula, n is an integer of 2 to 8.

[Chemical Formula 16]

&Lt; Synthesis of specific diamine >

In the present invention, a specific diamine can be obtained by synthesizing a dinitro group or a mononitro group having an amino group, which is protected by a protecting group which can be removed in a reduction step, through each step, and converting the nitro group into an amino group Followed by deprotection.

There are various methods for synthesizing the diamine precursor. For example, a method of synthesizing a site where radicals are generated by ultraviolet irradiation, introducing a spacer site, and then bonding the dinitrobenzene with dinitrobenzene will be described below. In the formula, n is an integer of 2 to 8.

[Chemical Formula 17]

In the case of the above reaction, hydroxyl groups are present at two points. However, they can be synthesized selectively by optimizing the kind of the base (catalyst) and the injection ratio.

The base to be used is not particularly limited, but is preferably an inorganic base such as potassium carbonate, sodium carbonate or cesium carbonate, or an organic base such as pyridine, dimethylaminopyridine, trimethylamine, triethylamine or tributylamine.

The method of reducing the dinitro compound as the diamine precursor is not particularly limited and a method in which a catalyst such as palladium carbon, platinum oxide, Raney nickel, platinum carbon, rhodium-alumina or platinum sulfide carbon is used as a catalyst and ethyl acetate, There is a method of performing reduction with a hydrogen gas, hydrazine, hydrogen chloride, or the like in a solvent such as hydrofluoric acid, hydrofluoric acid, hydrofluoric acid, hydrofluoric acid, hydrofluoric acid, hydrofluoric acid, An autoclave may be used as needed.

On the other hand, when the structure contains an unsaturated bonding site, the use of palladium carbon or platinum carbon reduces the unsaturated bond sites and may lead to saturation bonding. Therefore, preferable conditions include reduced iron, tin, tin chloride Or a reducing condition using poisoned palladium carbon, platinum carbon, iron-doped platinum carbon, or the like as a catalyst.

The diamine of the present invention can also be obtained by deprotecting a diaminobenzene derivative protected by a benzyl group or the like in the reduction step.

The specific diamine is preferably used in an amount of 10 to 80 mol%, more preferably 20 to 60 mol%, and particularly preferably 30 to 50 mol%, based on the diamine component used in the synthesis of the polyamic acid.

&Lt; Diamines having side chains for vertically orienting liquid crystals &gt;

As a method for introducing a side chain for orienting the liquid crystal vertically into the polyimide polymer, it is preferable to use a diamine having a specific side chain structure as a part of the diamine component. It is particularly preferable to use a diamine (also referred to as a specific side chain type diamine compound) represented by the following formula [2].

[Chemical Formula 18]

In the formula [2], X represents the structure represented by the formula [II-1] or the formula [II-2], n represents an integer of 1 to 4,

As the specific side chain type diamine, it is preferable to use a diamine represented by the following formula [2-1] in view of obtaining a high and stable vertical orientation of liquid crystal.

[Chemical Formula 19]

X ¹ , X ² , X ³ , X ⁴ , X ⁵ and n in the formula [2-1] are the same as defined in each of the above-mentioned formula [II-1] Preferred ones are the same as those defined in each of the above-mentioned formula [II-1].

In the formula [2-1], m is an integer of 1 to 4. Preferably an integer of 1.

Specific side chain type diamines specifically include, for example, the structures represented by the following formulas [2a-1] to [2a-31].

[Chemical Formula 20]

(Wherein R ¹ represents -O-, -OCH ₂ -, -CH ₂ O-, -COOCH ₂ - or -CH ₂ OCO-, R ² represents a linear or branched alkyl group having 1 to 22 carbon atoms, A linear or branched alkoxyl group having from 1 to 22 carbon atoms, a linear or branched, fluorine-containing alkyl group having from 1 to 22 carbon atoms, or a fluorine-containing alkoxyl group).

[Chemical Formula 21]

(R ³ represents -COO-, -OCO-, -CONH-, -NHCO-, -COOCH ₂ -, -CH ₂ OCO-, -CH ₂ O-, -OCH ₂ - or -CH ₂ - R ⁴ is a linear or branched alkyl group having 1 to 22 carbon atoms, a linear or branched alkoxyl group having 1 to 22 carbon atoms, a linear or branched linear or branched alkyl group having 1 to 22 carbon atoms, Practical skill).

[Chemical Formula 22]

(R ⁵ represents -COO-, -OCO-, -CONH-, -NHCO-, -COOCH ₂ -, -CH ₂ OCO-, -CH ₂ O-, -OCH ₂ -, -CH ₂ -, -O - or -NH-, and R ⁶ is a fluorine group, a cyano group, a trifluoromethane group, a nitro group, an azo group, a formyl group, an acetyl group, an acetoxy group or a hydroxyl group.

(23)

(R ⁷ is a linear or branched alkyl group having 3 to 12 carbon atoms, and the cis-trans isomer of 1,4-cyclohexylene is a trans isomer).

&Lt; EMI ID =

(R ⁸ is a linear or branched alkyl group having 3 to 12 carbon atoms, and the cis-trans isomer of 1,4-cyclohexylene is a trans isomer).

(25)

(A ₄ is a linear or branched alkyl group having 3 to 20 carbon atoms which may be substituted with a fluorine atom, A ₃ is a 1,4-cyclohexylene group or a 1,4-phenylene group, A ₂ is an oxygen atom or COO- * (provided that the combined hand tagged "*" in combination with a _3), and, a ₁ is an oxygen atom or - COO- (combined hand affixed However, "*" (CH ₂₎ a ₂₎ and Lt; / RTI &gt; A ₁ is an integer of 0 or 1, a ₂ is an integer of 2 to 10, and a ₃ is an integer of 0 or 1.

(26)

(27)

(28)

[Chemical Formula 29]

(30)

Of the above-mentioned formulas [2a-1] to [2a-31], particularly preferred are compounds represented by formulas [2a-1] to [2a-6], formulas [2a- 22] to formula [2a-31].

Examples of the diamine having a specific side chain structure represented by the above formula [II-2] include diamines represented by the following formulas [2b-1] to [2b-10].

(31)

(A &^lt; 1 &gt; represents an alkyl group having 1 to 22 carbon atoms or a fluorine-containing alkyl group).

(32)

(33)

(34)

In formula [2b-5] to formula [2b-10], A ¹ represents -COO-, -OCO-, -CONH-, -NHCO-, -CH ₂ -, -O-, -CO- or -NH -, A ² represents a linear or branched alkyl group having 1 to 22 carbon atoms or a linear or branched fluorine-containing alkyl group having 1 to 22 carbon atoms.

The diamine may be used alone or in combination of two or more thereof depending on the properties such as liquid crystal alignability, pretilt angle, voltage holding property, and accumulated charge when used as a liquid crystal alignment film.

The diamine having a side chain that vertically aligns the liquid crystal is preferably used in an amount of 5 to 50 mol%, more preferably 10 to 40 mol%, of the diamine component used in the synthesis of the polyamic acid, And preferably 15 to 30 mol%.

The use of a diamine having a side chain for vertically orienting a liquid crystal is particularly excellent in view of the improvement of the response speed and the ability to fix the liquid crystal alignment.

&Lt; Diamines containing photoreactive side chains &gt;

The diamine having a photoreactive side chain is, for example, a diamine having a side chain represented by the formula (3), specifically, a diamine represented by the following formula (3), but is not limited thereto .

(35)

(The definitions of R ⁸ , R ⁹ and R ^{10 in} the formula (3) are the same as those of the formula (III).)

The bonding position of two amino groups (-NH ₂ ) in the formula (3) is not limited. Specifically, with respect to the coupler of the side chain, the position of 2,3, the position of 2, the position of 2,5, the position of 2,6, the position of 3, 4, the position of 3, 5 on the benzene ring . Of these, from the viewpoint of reactivity in the synthesis of polyamic acid, the positions of 2,4, 2,5, or 3,5 are preferable. When the ease of synthesis of the diamine is also considered, the position of 2,4 or the position of 3,5 is more preferable.

Specific examples of the diamine having a photoreactive side chain include the following.

(36)

(X ⁹ and X ¹⁰ each independently represent a single bond, -O-, -COO-, -NHCO-, or -NH-, and Y represents an alkylene group having 1 to 20 carbon atoms which may be substituted with a fluorine atom .)

Examples of the diamine having a photoreactive side chain include a group causing a photodimerization reaction represented by the following formula and a diamine having a group generating a photopolymerization reaction in a side chain.

(37)

Y ₁ represents -CH ₂ -, -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, or -CO-. Y ₂ is an alkylene group having 1 to 30 carbon atoms, a divalent carbon ring or a heterocyclic ring, and one or more hydrogen atoms of the alkylene group, divalent carbon ring or heterocyclic ring may be substituted with a fluorine atom or an organic group do. Y ₂ may be substituted with -CH ₂ - when the following groups are not adjacent to each other; -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, -CO-. Y ₃ represents -CH ₂ -, -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, -CO-, or a single bond. Y ₄ represents a new namoyl group. Y ₅ is a single bond, an alkylene group having 1 to 30 carbon atoms, a divalent carbon ring or a heterocyclic ring, and one or more hydrogen atoms of the alkylene group, divalent carbon ring or heterocyclic ring may be substituted with a fluorine atom or an organic group . Y ₅ may be substituted with -CH ₂ - when the following groups are not adjacent to each other; -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, -CO-. Y ₆ represents a photopolymerizable group which is an acrylic group or a methacryl group.

Specific examples of the diamine having a group causing a photodimerization reaction and a group causing a photopolymerization reaction in the side chain include, but are not limited to, the following.

(38)

The diamine may be used singly or in combination of two or more types depending on the properties of the liquid crystal alignment film, such as the liquid crystal alignment property, the pretilt angle, the voltage holding property, the charge accumulation, and the response speed of the liquid crystal display device .

The diamine having a photoreactive side chain is preferably used in an amount of 10 to 70 mol%, more preferably 20 to 60 mol%, and particularly preferably 30 to 60 mol%, based on the diamine component used in the synthesis of the polyamic acid. 50 mol%.

<Other diamines>

Further, in the case of producing the polyimide precursor and / or polyimide, other diamines other than the diamines described above can be used in combination as the diamine component, so long as the effect of the present invention is not impaired. Specific examples thereof include aromatic diamines such as p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, m- Dimethyl-m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,5-diaminophenol, 2,4-diaminophenol, 3,5- Diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol, 4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'- Diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 3,3'-dicarboxy- 4,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-biphenyl, 3,3'-trifluoromethyl-4,4'-diaminobiphenyl, 3,4 Diaminobiphenyl, 3,3'-diaminobiphenyl, 2,2'-diaminobiphenyl, 2,3'-diaminobiphenyl, 4,4'-diaminodiphenylmethane, 3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2'-diaminodiphenylmethane, 2,3'-diamino Phenylmethane, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,3 (4-aminophenyl) silane, bis (3-aminophenyl) silane, dimethyl-bis (4-aminophenyl) Aminophenyl) silane, dimethyl-bis (3-aminophenyl) silane, 4,4'-thiodianiline, 3,3'- thiodianiline, 4,4'- diaminodiphenylamine, Diaminodiphenylamine, 3,4'-diaminodiphenylamine, 2,2'-diaminodiphenylamine, 2,3'-diaminodiphenylamine, N-methyl (4,4'-diamino (3,3'-diaminodiphenyl) amine, N-methyl (3,4'-diaminodiphenyl) amine, N-methyl (2,2'-diaminodiphenyl) ) Amine, N-methyl (2,3'-diaminodiphenyl) amine, 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, , 4-diaminonaphthalene, 2,2'-diaminobenzophene , 2,3'-diaminobenzophenone, 1,5-diaminonaphthalene, 1,6-diaminonaphthalene, 1,7-diaminonaphthalene, 1,8-diaminonaphthalene, Bis (4-aminophenyl) ethane, 1,2-bis (3-aminophenyl) ethane, 2,6-diaminonaphthalene, 2,6-diaminonaphthalene, Bis (4-aminophenyl) propane, 1,3-bis (3-aminophenyl) propane, ) Butane, bis (3,5-diethyl-4-aminophenyl) methane, 1,4-bis (4-aminophenoxy) benzene, (4-aminophenyl) benzene, 1,3-bis (4-aminophenoxy) benzene, 4,4 '- [1,4-phenylenebis (methylene)] dianiline, 4,4' - [ Phenylenbis (methylene)] dianiline, 3,3 '- [1,4-phenyl Phenylenebis [(4-aminophenyl) methanone], 1,4-phenylenebis (methylene)] dianiline, Phenylenebis [(3-aminophenyl) methanone], 1,3-phenylenebis [(4-aminophenyl) methanone] Phenylenebis (4-aminobenzoate), 1,4-phenylenebis (3-aminobenzoate), 1,3- (3-aminophenyl) isophthalate, bis (3-aminophenyl) isophthalate, bis (3-aminophenyl) isophthalate, bis , N, N '- (1,4-phenylene) bis (4-aminobenzamide) (4-aminobenzamide), N, N '- (1,3-phenylene) bis (3-aminobenzamide), N, N'- ) Terephthalamide, N, N'-bis (3-aminophenyl) terephthalate Bis (4-aminophenyl) isothiamides, N, N'-bis (3-aminophenyl) isophthalamide, 9,10- Bis [4- (4-aminophenoxy) phenyl] propane, 2,2'-bis [4- Bis (3-aminophenyl) hexafluoropropane, 2,2'-bis (3-aminophenyl) hexafluoropropane, 2,2'- Bis (3-aminophenyl) propane, 2,2'-bis (3-amino- Bis (4-aminophenoxy) propane, 1,3-bis (3-aminophenoxy) propane, Bis (4-aminophenoxy) butane, 1,5-bis (4-aminophenoxy) Bis (4-aminophenoxy) pentane, 1,6-bis (4-aminophenoxy) (3-aminophenoxy) hexane, 1,7-bis (4-aminophenoxy) heptane, 1,7- Bis (3-aminophenoxy) octane, 1,9-bis (3-aminophenoxy) (3-aminophenoxy) undecane, 1,11- (3-aminophenoxy) undecane, 1,12- (4-aminocyclohexyl) methane, bis (4-amino-3-methylcyclohexyl) dicyclohexylcarbodiimide, Methane and the like, aliphatic diamines such as 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7- - aliphatic diamines such as diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, and 1,12-diaminododecane.

The other diamine may be used alone or in combination of two or more thereof depending on the properties such as liquid crystal alignability, pretilt angle, voltage holding property, and accumulated charge when the liquid crystal alignment film is used.

&Lt; Tetracarboxylic acid dianhydride &gt;

The tetracarboxylic acid dianhydride component to be reacted with the diamine component is not particularly limited. Specific examples include pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid, 2,3,6,7-anthracene tetracarboxylic acid, 1,2,5,6-anthracene tetracarboxylic acid, 3,3 ', 4,4'-biphenyltetracarboxylic acid, 2,3,3 (3,4-dicarboxyphenyl) ether, 3,3 ', 4,4'-benzophenonetetracarboxylic acid, bis (3,4-dicarboxyphenyl) Sulfone, bis (3,4-dicarboxyphenyl) methane, 2,2-bis (3,4-dicarboxyphenyl) propane, 1,1,1,3,3,3-hexafluoro-2,2- (3,4-dicarboxyphenyl) propane, bis (3,4-dicarboxyphenyl) dimethylsilane, bis (3,4-dicarboxyphenyl) diphenylsilane, 2,3,4,5- (3,4-dicarboxyphenyl) pyridine, 3,3 ', 4,4'-diphenylsulfone tetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid Acid, 1,3-diphenyl-1,2,3,4-cyclobutanetetracar Oxydipetetracarboxylic acid, 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,2,4,5-cyclohexane Tetracarboxylic acid, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutane tetracarboxylic acid, 1,2-dimethyl-1,2,3,4-cyclobutane tetracarboxyl Acid, 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic acid, 1,2,3,4-cycloheptane tetracarboxylic acid, 2,3,4,5-tetrahydrofuran tetra Carboxylic acid, 3,4-dicarboxy-1-cyclohexylsuccinic acid, 2,3,5-tricarboxycyclopentylacetic acid, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene Succinic acid, bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic acid, bicyclo [4,3,0] nonane-2,4,7,9-tetracarboxylic acid, Bicyclo [4,4,0] decane-2,4,7,9-tetracarboxylic acid, bicyclo [4,4,0] decane-2,4,8,10-tetracarboxylic acid, tricyclo [6.3.0.0 &lt; 2,6 &gt;] undecane-3,5,9,11-tetracarboxylic acid, 1,2,3,4-butanetetracarboxylic acid, 4- (2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4-tetrahydronaphthalene- 2,2,2] oct-7-ene-2,3,5,6-tetracarboxylic acid, 5- (2,5-dioxotetrahydrofuryl) -3-methyl- - cyclohexane-1,2-dicarboxylic acid, tetracyclo [6,2,1,1,0,2,7] dodeca-4,5,9,10-tetracarboxylic acid, 3,5, Tetracarboxylic dianhydrides obtained from 6-tricarboxy norbornane-2: 3,5: 6 dicarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid and the like. Of course, the tetracarboxylic acid dianhydride may be used alone or in combination of two or more, depending on the properties such as liquid crystal alignability, voltage holding characteristics, and accumulated charge when the liquid crystal alignment film is used.

&Lt; Component (B) &gt;

The liquid crystal aligning agent of the present invention is a polyimide precursor obtained by using as a component (B) a diamine component containing at least one kind of diamine selected from the following formulas (B-1) to (B-5) A tetracarboxylic acid dianhydride component containing a polymer selected from polyimide obtained by imidizing a polyimide precursor or at least one tetracarboxylic acid dianhydride selected from the following formulas (3) and (4) A polyimide precursor obtained by a reaction of a diamine, and a polymer selected from a polyimide obtained by imidizing the polyimide precursor.

[Chemical Formula 39]

(40)

When at least one kind of tetracarboxylic acid dianhydride selected from the above-mentioned formulas (3) and (4) is used as a raw material, it is preferable that the material interacts with [liquid crystal-orientation film] Can be improved. Examples of the tetracarboxylic acid dianhydride represented by the formulas selected from the formulas (3) and (4) include, but are not limited to, the following compounds.

(41)

At least one tetracarboxylic acid dianhydride selected from the above-mentioned formulas (1-1) to (1-4) is a tetracarboxylic acid dianhydride component used in the synthesis of the component (B) It is preferable to use an amount of 10 to 100%. It is more preferable to use 10 to 60%.

In addition, the tetracarboxylic acid dianhydride other than the above-mentioned formulas (1-1) to (1-4) may be used as a raw material for the component (B), as long as the effect of the present invention is not impaired. Specific examples include the tetracarboxylic acid dianhydride described as the component (A), but are not limited thereto.

For example, when a tetracarboxylic acid dianhydride having an aliphatic group or an alicyclic group is also used as a raw material, the amount of the tetracarboxylic acid dianhydride is preferably from 0 to 90% of the tetracarboxylic acid dianhydride component used in the synthesis of the component (B) Is preferably used.

When at least one tetracarboxylic acid dianhydride selected from the above-mentioned formulas (1-1) to (1-4) is used as the component (B), the diamine component to be reacted is not particularly limited, Include the diamines exemplified as the component (A), but the use of at least one diamine selected from the above-mentioned formulas (B-1) to (B-5) is preferable from the viewpoint of the accumulated charge characteristics.

The polymer as the component (B) is preferably a polyimide precursor obtained by using as a raw material a diamine component containing at least one kind of diamine selected from the following formulas (B-1) to (B-5) Or a polyimide obtained by imidizing a polyimide.

(42)

(Wherein Y ₁ represents a secondary amine, a tertiary amine, or a monovalent organic group having a heterocyclic structure, and Y ₂ represents a secondary amine, a tertiary amine, or a divalent organic group having a heterocyclic structure. )

At least one diamine having a specific structure having a high polarity and selected from the above formulas (B-1) to (B-5), or a diamine having a carboxyl group and a diamine having a nitrogen- By using at least one of them in combination, the charge transfer is promoted by electrostatic interaction such as salt formation or hydrogen bonding, so that the accumulated charge characteristics can be improved. Examples of the at least one diamine selected from the above-mentioned formulas (B-1) to (B-5) include the following diamines, but are not limited thereto.

(43)

The polymer as the component (B) may be a diamine having a side chain that vertically aligns the liquid crystal used in the component (A).

The at least one diamine selected from the above-mentioned formulas (B-1) to (B-5) is preferably a diamine in an amount of 10 mol% to 80 mol% of the diamine component used in the synthesis of the polyamic acid (B) Is preferably used.

When at least one kind of diamine selected from the above-mentioned formulas (B-1) to (B-5) is used, the tetracarboxylic acid dianhydride component to be reacted is not particularly limited, Tetracarboxylic acid dianhydride exemplified as the component can be mentioned. However, the use of at least one tetracarboxylic acid dianhydride selected from the above-mentioned formulas (3) and (4) is preferable from the viewpoint of reduction of accumulated charge.

<Polymerizable compound>

The liquid crystal aligning agent of the present invention may contain a polymerizable compound having a group capable of photopolymerization or photo-crosslinking at two or more ends, if necessary. Such a polymerizable compound is a compound having two or more terminals having a group capable of photopolymerization or photo-crosslinking. Here, the polymerizable compound having a photopolymerizable group is a compound having a functional group that causes polymerization by irradiation of light. The compound having a photocrosslinking group is a compound having a photocrosslinking group that reacts with at least one polymer selected from a polymer of a polymerizable compound, a polyimide precursor, and a polyimide obtained by imidizing the polyimide precursor, And a functional group capable of crosslinking. Further, the compound having a photo-crosslinkable group also reacts with the compound having a photo-crosslinkable group.

By using the liquid crystal aligning agent of the present invention containing the above polymerizable compound in a liquid crystal display device of a vertical alignment type such as an SC-PVA type liquid crystal display, side chains and photoreactive side chains for orienting the liquid crystal vertically The reaction speed can be remarkably improved and the response speed can be sufficiently improved even when the amount of the polymerizable compound to be added is smaller than that of the polymer having the polymerizable compound alone.

Examples of the photopolymerization or photo-crosslinking group include a monovalent group represented by the following formula (IV).

(44)

(R ¹² represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms) Z ¹ Represents a divalent aromatic ring or heterocyclic ring which may be substituted with an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms. Z ² represents a monovalent aromatic ring or heterocyclic ring which may be substituted by an alkyl group having 1 to 12 carbon atoms or an alkoxyl group having 1 to 12 carbon atoms.

Specific examples of the polymerizable compound include a compound having a group capable of photo-polymerizing at each of two terminals represented by the following formula (V), a terminal having a group capable of photo-crosslinking with a terminal having a group capable of photo-polymerizing represented by the following formula (VI) , Or a compound having a group capable of photo-crosslinking at each of two terminals represented by the following formula (VII).

Further, according to the following formula (V) ~ (VII), R 12, Z 1 and Z ² are the same as R ^12, Z ¹ and Z ² in the formula (IV) and, Q ¹ is a divalent organic group to be. Q ¹ has a cyclic structure such as a phenylene group (-C ₆ H ₄ -), a biphenylene group (-C ₆ H ₄ -C ₆ H ₄ -), or a cyclohexylene group (-C ₆ H ₁₀ -) . This is because the interaction with the liquid crystal tends to become large.

[Chemical Formula 45]

(46)

(47)

Specific examples of the polymerizable compound represented by the formula (V) include a polymerizable compound represented by the following formula (4). In the formula (4), V and W are each a single bond or -R ¹ O-, R ¹ is a linear or branched alkylene group having 1 to 10 carbon atoms, preferably -R ¹ O-, and R &lt; ¹ &gt; is a linear or branched alkylene group having 2 to 6 carbon atoms. V and W may be the same or different, but if they are the same, synthesis is easy.

(48)

Further, even when a polymerizable compound which is not a? -Methylene-? -Butyrolactone group and has an acrylate group or a methacrylate group as a photopolymerization or photocrosslinking group, the acrylate group or the methacrylate group may be a spacer such as an oxyalkylene group , The polymerizable compound having a structure bonded to the phenylene group can remarkably improve the response speed particularly in the same manner as the polymerizable compound having an? -Methylene-? -Butyrolactone group at both ends. The polymerizable compound having a structure in which an acrylate group or a methacrylate group is bonded to a phenylene group through a spacer such as an oxyalkylene group has improved stability to heat and has been obtained at a high temperature, It can withstand enough.

<Synthesis of polyamic acid>

When a polyamic acid is obtained by reacting a diamine component with a tetracarboxylic acid dianhydride, a known synthetic method can be used. Generally, it is a method of reacting a diamine component and a tetracarboxylic acid dianhydride component in an organic solvent. The reaction between the diamine component and the tetracarboxylic acid dianhydride is advantageous in that it proceeds relatively easily in an organic solvent and does not generate by-products.

The organic solvent used in the reaction is not particularly limited as long as it dissolves the produced polyamic acid. An organic solvent in which the polyamic acid does not dissolve may be mixed with the solvent in the range that the produced polyamic acid is not precipitated. In addition, water in the organic solvent inhibits the polymerization reaction, and further causes hydrolysis of the produced polyamic acid. Therefore, it is preferable to use an organic solvent that is dehydrated and dried.

Examples of the organic solvent used in the reaction include N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethylformamide, N-methylformamide, Pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, 3-methoxy-N, N-dimethylpropanamide, N- But are not limited to, lactam, dimethylsulfoxide, tetramethylurea, pyridine, dimethylsulfone, hexamethyl sulfoxide,? -Butyrolactone, isopropyl alcohol, methoxymethyl pentanol, dipentene, ethyl amyl ketone, , Methyl isoamyl ketone, methyl isopropyl ketone, methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, butyl cellosolve acetate, ethyl cellosolve acetate, butyl carbitol, ethyl carbitol, ethylene glycol , Ethylene glycol monoacetate, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether , Propylene glycol, propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monobutyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, diethylene glycol, diethylene glycol Monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, dipropylene Glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether , Diisobutyl Butyl ether, diisobutyl ketone, methylcyclohexene, propyl ether, dihexyl ether, dioxane, n-hexane, n-pentane, n-octane, diethyl ether, cyclohexanone, ethylene Propyleneglycol monoethyl ether, methyl pyruvate, methyl pyruvate, methyl 3-methoxypropionate, methyl 3-ethoxypropionate, methyl ethyl ketone, methyl lactate, Methoxypropionate, propyl 3-methoxypropionate, butyl 3-methoxypropionate, diglyme, 4-hydroxy-4-methyl-2-pentanone, 2-ethyl-1-hexanol and the like. These organic solvents may be used alone or in combination.

The method of reacting the diamine component and the tetracarboxylic acid dianhydride component in an organic solvent can be carried out by stirring the solution in which the diamine component is dispersed or dissolved in an organic solvent and stirring the solution so that the tetracarboxylic acid dianhydride component is dispersed in the organic solvent, A method in which a diamine component is added to a solution in which a tetracarboxylic acid dianhydride component is dispersed or dissolved in an organic solvent, a method in which a tetracarboxylic acid dianhydride component and a diamine component are alternately added It may be. When the diamine component or the tetracarboxylic acid dianhydride component is composed of a plurality of compounds, they may be reacted in a preliminarily mixed state, or they may be sequentially reacted individually, or the low molecular weight compounds reacted individually may be mixed and reacted, May be used.

The temperature at which the diamine component and the tetracarboxylic acid dianhydride component are reacted is, for example, in the range of -20 占 폚 to 150 占 폚, preferably -5 占 폚 to 100 占 폚. In the reaction, the total concentration of the diamine component and the tetracarboxylic acid dianhydride component is preferably 1 to 50 mass%, more preferably 5 to 30 mass%, relative to the reaction solution, for example.

The ratio of the total molar amount of the tetracarboxylic acid dianhydride component to the total molar amount of the diamine component in the above polymerization reaction can be selected according to the molecular weight of the polyamic acid to be obtained. As the molar ratio is closer to 1.0, the molecular weight of the produced polyamic acid becomes larger and, in the same way as the usual polycondensation reaction, it is 0.8 to 1.2, indicating a preferable range.

The method for synthesizing the polyamic acid to be used in the present invention is not limited to the above method. Instead of the tetracarboxylic acid dianhydride, a tetracarboxylic acid or tetracarboxylic acid The corresponding polyamic acid can also be obtained by using a tetracarboxylic acid derivative such as an acid halide or the like and reacting it by a known method.

Examples of the method of imidizing the polyamic acid to form polyimide include thermal imidization in which a solution of polyamic acid is heated as it is, and catalyst imidization in which a catalyst is added to a solution of polyamic acid. In addition, the imidation rate from polyamic acid to polyimide does not necessarily have to be 100%.

The temperature at which the polyamic acid is thermally imidized in the solution is 100 ° C to 400 ° C, preferably 120 ° C to 250 ° C, and it is preferable to carry out the removal while removing the water generated by the imidization reaction out of the system.

The catalyst imidation of polyamic acid can be carried out by adding a basic catalyst and acid anhydride to a solution of polyamic acid and stirring at -20 to 250 캜, preferably 0 to 180 캜. The amount of the basic catalyst is 0.5 to 30 moles, preferably 2 to 20 moles, of the amide group, and the amount of the acid anhydride is 1 to 50 moles, preferably 3 to 30 moles, of the amide group. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, trioctylamine, etc. Among them, pyridine is preferred because it has a basicity suitable for proceeding the reaction. As the acid anhydride, acetic anhydride, trimellitic anhydride, pyromellitic anhydride and the like can be given. Of these, use of acetic anhydride is preferable since the purification after completion of the reaction becomes easy. The imidization rate by the catalyst imidization can be controlled by adjusting the catalyst amount, the reaction temperature, and the reaction time.

The polyamic acid ester can be produced by reacting a tetracarboxylic acid diester dichloride with a diamine in the same manner as in the synthesis of the polyamic acid or by reacting a diamine having the same structure as that of the tetracarboxylic acid diester with the polyamic acid in the presence of a suitable condensing agent or base And the like. It is also possible to synthesize a polyamic acid in advance by the above method and to esterify the carboxylic acid in the amic acid using a polymer reaction. Specifically, for example, the tetracarboxylic acid diester dichloride and diamine are reacted in the presence of a base and an organic solvent at -20 ° C to 150 ° C, preferably 0 ° C to 50 ° C for 30 minutes to 24 hours, Can be reacted for 1 hour to 4 hours to synthesize a polyamic acid ester. The polyimide can also be obtained by heating the polyamic acid ester at a high temperature to accelerate the depolarization and ring closure.

When a polyimide precursor or polyimide such as polyamic acid, polyamic acid ester or the like is recovered from the reaction solution, the reaction solution may be put into a poor solvent and precipitated. Examples of poor solvents to be used in the precipitation include methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene and water. The polymer precipitated by charging into a poor solvent can be recovered by filtration and then dried at normal temperature or under reduced pressure or by heating. Further, when the recovered polymer is redissolved in an organic solvent and the operation of reprecipitation and recovery is repeated 2 to 10 times, impurities in the polymer can be reduced. As the poor solvent at this time, for example, alcohols, ketones, hydrocarbons and the like can be mentioned. When three or more poor solvents selected from these are used, the purification efficiency is further increased, which is preferable.

<Liquid Crystal Aligner>

The liquid crystal aligning agent of the present invention contains at least one polymer having a structure represented by the above formula (1) in a side chain, but the content of such a polymer is preferably from 1 to 20 mass%, more preferably from 3 to 15 mass% %, Particularly preferably 3 to 10% by mass. When two or more terminals each contain a polymerizable compound having a photo-polymerization or photo-crosslinking group, the content thereof is preferably from 1 to 50 parts by mass, more preferably from 5 to 30 parts by mass, per 100 parts by mass of the polymer Wealth.

The liquid crystal aligning agent of the present invention may contain a polymer other than the above-mentioned polymer. At this time, the content of such another polymer in the entire polymer component is preferably from 0.5 to 80% by mass, and more preferably from 20 to 50% by mass.

 The molecular weight of the polymer having the liquid crystal aligning agent is preferably in the range of from 0.1 to 10 parts by weight based on the weight average molecular weight measured by GPC (Gel Permeation Chromatography) method in consideration of the strength of the liquid crystal alignment film obtained by applying the liquid crystal aligning agent, The molecular weight is preferably 5,000 to 1,000,000, more preferably 10,000 to 150,000.

The solvent contained in the liquid crystal aligning agent is not particularly limited and includes a polymer having a structure represented by the above formula (1) in its side chain, and a polymer having two or more terminals that are photopolymerized or photo- And a compound capable of dissolving or dispersing a component containing the compound. For example, organic solvents such as those exemplified in the synthesis of the polyamic acid may be mentioned. Among them, N-methyl-2-pyrrolidone,? -Butyrolactone, N-ethyl-2-pyrrolidone, Dimethyl propanamide is preferable from the viewpoint of solubility. Of course, two or more types of mixed solvents may be used.

It is also preferable to use a solvent which improves the uniformity and smoothness of the coating film in a solvent having high solubility for the component containing the liquid crystal aligning agent. Such solvents include, for example, isopropyl alcohol, methoxymethyl pentanol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl cellosolve acetate, butyl cellosolve acetate, ethyl cellosolve acetate Propylene glycol monoacetate, propylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether, Glycol monobutyl ether, propylene glycol-tert-butyl ether, dipropylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl Ether, dipropylene glycol monomethyl ether, pro Dipropylene glycol monoacetate monoethyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monoacetate monopropyl ether, 3-methyl-3-methoxybutyl acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether, dipropylene glycol monoacetate monoethyl ether, Propylene glycol monomethyl ether, tripropylene glycol methyl ether, 3-methyl-3-methoxybutanol, diisopropyl ether, ethyl isobutyl ether, diisobutylene, amyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, But are not limited to, ether, dihexyl ether, n-hexane, n-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, Ethyl, methyl 3-methoxypropionate, methylethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropyl Methoxypropionate, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, Propylene glycol monoacetate, propylene glycol-1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2 - (2-ethoxypropoxy) propanol, lactic acid methyl ester, lactic acid ethyl ester, n-propyl lactate, n-butyl lactate, lactic acid isoamyl ester and 2-ethyl-1-hexanol . These solvents may be mixed with a plurality of kinds. These solvents are preferably used in an amount of 5 to 80 mass%, more preferably 20 to 60 mass%, of the total solvent contained in the liquid crystal aligning agent.

The liquid crystal aligning agent may contain components other than those described above. Examples thereof include a compound which improves film thickness uniformity and surface smoothness when the liquid crystal aligning agent is applied, and a compound which improves the adhesion between the liquid crystal alignment film and the substrate.

Examples of the compound that improves film thickness uniformity and surface smoothness include a fluorine-based surfactant, a silicon-based surfactant, and a nonionic surface-active agent. (Manufactured by Tohchem Products), Megafac F171, F173, R-30 (manufactured by Dainippon Ink & Chemicals, Incorporated), Fluorad FC430 and FC431 (manufactured by Sumitomo 3M), EF301, EF303 and EF352 , Asahi Guard AG710, Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by Asahi Glass Co., Ltd.). The proportion of these surfactants to be used is preferably 0.01 to 2 parts by mass, more preferably 0.01 to 1 part by mass based on 100 parts by mass of the total amount of the polymer contained in the liquid crystal aligning agent.

Specific examples of the compound that improves the adhesion between the liquid crystal alignment layer and the substrate include a functional silane-containing compound and an epoxy group-containing compound. For example, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3 3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxy (2-aminoethyl) Aminopropyltriethoxysilane, N-trimethoxysilylpropyltriethoxysilane, N-trimethoxysilylpropyltriethoxysilane, N-trimethoxysilylpropyltriethoxysilane, N-trimethoxysilylpropyltriethoxysilane, Amine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl Acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N- Bis (oxyethylene) -3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N- Aminopropyltriethoxysilane, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neo Pentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6 -Tetraglycidyl-2,4-hexanediol, N, N, N ', N'-tetraglycidyl-m-xylylenediamine, 1,3-bis (N, N-diglycidylaminomethyl ) N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylmethane, 3- (N-allyl-N-glycidyl) aminopropyltrimethoxysilane, 3- (N, N-diglycidyl) And the like can be given no trimethoxysilane.

In order to further increase the film strength of the liquid crystal alignment film, a phenol compound such as 2,2'-bis (4-hydroxy-3,5-dihydroxymethylphenyl) propane or tetra (methoxymethyl) bisphenol may be added. These compounds are preferably added in an amount of 0.1 to 30 parts by mass, more preferably 1 to 20 parts by mass, per 100 parts by mass of the total amount of the polymer contained in the liquid crystal aligning agent.

The liquid crystal aligning agent may be added with a dielectric material or a conductive material for the purpose of changing electric characteristics such as dielectric constant and conductivity of the liquid crystal alignment film as long as the effect of the present invention is not impaired.

By applying this liquid crystal aligning agent on the substrate and baking it, a liquid crystal alignment film for vertically aligning the liquid crystal can be formed. By using the liquid crystal aligning agent of the present invention, the response speed of the liquid crystal display element using the obtained liquid crystal alignment film can be made fast. The polymerizable compound each having a photopolymerization or photocrosslinking group at two or more terminals, which may be contained in the liquid crystal aligning agent of the present invention, is not contained in the liquid crystal aligning agent, or is contained in the liquid crystal together with the liquid crystal aligning agent , So-called PSA mode, the photoreaction becomes highly sensitive, and a tilt angle can be given even with a small amount of ultraviolet radiation.

For example, a cured film obtained by applying the liquid crystal aligning agent of the present invention to a substrate, drying it if necessary, and baking it may be used as it is as a liquid crystal alignment film. Alternatively, the cured film may be rubbed, irradiated with polarized light or light of a specific wavelength, treated with an ion beam or the like, or UV may be irradiated with a voltage applied to the liquid crystal display element after liquid crystal filling as the PSA orientation film . In particular, it is useful to use it as an alignment film for PSA.

The substrate to be used is not particularly limited as long as it is a substrate having high transparency and may be a glass plate, polycarbonate, poly (meth) acrylate, polyethersulfone, polyarylate, polyurethane, polysulfone, polyether, , Plastic substrates such as trimethylpentene, polyolefin, polyethylene terephthalate, (meth) acrylonitrile, triacetylcellulose, diacetylcellulose, and acetate butyrate cellulose. It is preferable to use a substrate on which an ITO electrode or the like for liquid crystal driving is formed from the viewpoint of process simplification. In a reflective liquid crystal display element, an opaque material such as a silicon wafer can be used only for a substrate on one side, and a material for reflecting light such as aluminum can be used as the electrode in this case.

The method of applying the liquid crystal aligning agent is not particularly limited, and examples thereof include a printing method such as screen printing, offset printing and flexographic printing, an ink jet method, a spray method, a roll coating method, a dip, a roll coater, a slit coater, have. From the viewpoint of productivity, the transfer printing method is widely used industrially and is preferably used in the present invention.

The coating film formed by applying the liquid crystal aligning agent by the above method may be fired to form a cured film. The drying step after the application of the liquid crystal aligning agent is not necessarily required, but it is preferable to carry out the drying step when the time from the application to the firing is not constant for each substrate or when the firing is not performed immediately after application. The drying may be carried out as long as the solvent is removed to such an extent that the coating film shape is not deformed by, for example, conveyance of the substrate, and the drying means is not particularly limited. For example, a method of drying on a hot plate at a temperature of 40 ° C to 150 ° C, preferably 60 ° C to 100 ° C, for 0.5 minutes to 30 minutes, preferably for 1 minute to 5 minutes.

The firing temperature of the coating film formed by applying the liquid crystal aligning agent is not limited and is, for example, 100 to 350 占 폚, preferably 120 to 300 占 폚, and more preferably 150 to 250 占 폚. The baking time is from 5 minutes to 240 minutes, preferably from 10 minutes to 90 minutes, and more preferably from 20 minutes to 90 minutes. The heating can be carried out by a generally known method, for example, a hot plate, a hot air circulation path, an infrared ray or the like.

The thickness of the liquid crystal alignment film obtained by baking is not particularly limited, but is preferably 5 to 300 nm, and more preferably 10 to 100 nm.

<Liquid crystal display element>

In the liquid crystal display element of the present invention, after the liquid crystal alignment film is formed on the substrate by the above method, a liquid crystal cell can be manufactured by a known method. As a specific example of the liquid crystal display element, there are two substrates arranged so as to face each other, a liquid crystal layer formed between the substrate and the liquid crystal layer, and a liquid crystal cell having the liquid crystal alignment film formed by the liquid crystal aligning agent of the present invention The liquid crystal display device of the vertical alignment type is a liquid crystal display device having a vertical alignment method. Specifically, a liquid crystal alignment film is formed by applying the liquid crystal aligning agent of the present invention on two substrates and firing, and two substrates are arranged so that the liquid crystal alignment films face each other. A liquid crystal layer And a liquid crystal cell formed by placing a liquid crystal layer in contact with a liquid crystal alignment layer and irradiating ultraviolet rays while applying a voltage to the liquid crystal alignment layer and the liquid crystal layer.

It is possible to polymerize the polymerizable compound by irradiating ultraviolet rays while applying a voltage to the liquid crystal alignment film and the liquid crystal layer using the liquid crystal alignment film formed by the liquid crystal aligning agent of the present invention, By reacting the photoreactive side chain of the polymer with the polymerizable compound, the orientation of the liquid crystal is more efficiently fixed, and the liquid crystal display element is remarkably excellent in the response speed.

The substrate used in the liquid crystal display element of the present invention is not particularly limited as long as it is a substrate having high transparency, but is usually a substrate on which a transparent electrode for driving liquid crystal is formed. Specific examples include the same substrates as those described above for the liquid crystal alignment film. A substrate having a conventional electrode pattern or a projection pattern may be used. In the liquid crystal display element of the present invention, however, since the liquid crystal aligning agent of the present invention is used, It is possible to operate in a structure in which an electrode pattern is formed and a counter substrate is not provided with a slit pattern or a projection pattern. With the liquid crystal display element having such a structure, the process at the time of manufacturing can be simplified and a high transmittance can be obtained .

In a high-performance device such as a TFT-type device, a device such as a transistor is formed between an electrode for liquid crystal driving and a substrate.

In the case of a transmissive liquid crystal display element, it is common to use such a substrate, but in a reflective liquid crystal display element, it is possible to use an opaque substrate such as a silicon wafer only on a substrate on one side. At this time, a material such as aluminum that reflects light may be used for the electrode formed on the substrate.

The liquid crystal material constituting the liquid crystal layer of the liquid crystal display element of the present invention is not particularly limited and liquid crystal materials used in conventional vertical alignment methods such as MLC-6608 and MLC-6609 manufactured by Merck, Liquid crystal can be used. In the PSA mode, for example, a liquid crystal containing a polymerizable compound represented by the following formula can be used.

(49)

In the present invention, as a method of sandwiching the liquid crystal layer between two substrates, known methods can be mentioned. For example, a pair of substrates on which a liquid crystal alignment film is formed is prepared, spacers such as beads are dispersed on a liquid crystal alignment film of one of the substrates, and the other side of the substrate is bonded (Bonded), and the liquid crystal is injected under reduced pressure and sealed. A pair of substrates on which a liquid crystal alignment film is formed is prepared, a spacer such as beads is dispersed on a liquid crystal alignment film of one of the substrates, and liquid crystal is dropped thereon. Thereafter, A liquid crystal cell can also be manufactured by a method in which one substrate is bonded and encapsulated. The thickness of the spacer is preferably 1 to 30 占 퐉, more preferably 2 to 10 占 퐉.

The step of forming the liquid crystal cell by irradiating ultraviolet rays while applying a voltage to the liquid crystal alignment film and the liquid crystal layer is performed by applying an electric field to the liquid crystal alignment film and the liquid crystal layer by applying a voltage between the electrodes provided on the substrate, And a method of irradiating ultraviolet rays while maintaining the electric field. Here, the voltage applied between the electrodes is, for example, 5 to 30 Vp-p, preferably 5 to 20 Vp-p. The irradiation amount of ultraviolet rays is, for example, 1 to 60 J, preferably 40 J or less. When the amount of ultraviolet radiation is small, reliability deterioration caused by destruction of members constituting the liquid crystal display element can be suppressed, The time can be reduced and the production efficiency is increased.

As described above, when ultraviolet rays are irradiated while a voltage is applied to the liquid crystal alignment film and the liquid crystal layer, the polymerizable compound reacts to form a polymer, and the direction in which the liquid crystal molecules are tilted by the polymer is stored, Can speed up. When ultraviolet rays are irradiated while a voltage is applied to the liquid crystal alignment film and the liquid crystal layer, a side chain for vertically orienting the liquid crystal, a polyimide precursor having a photoreactive side chain, and a polyimide precursor obtained by imidizing the polyimide precursor , The light-reactive side chains of the polymer and the photoreactive side chains of the polymer react with each other, so that the response speed of the resulting liquid crystal display element can be increased.

Example

Hereinafter, the present invention will be described in more detail based on examples, but the present invention is not limited at all by these examples.

&Lt; Synthesis of liquid crystal aligning agent &gt;

The abbreviations used in the preparation of the following liquid crystal aligning agent are as follows.

(Acid anhydride)

BODA: bicyclo [3,3,0] octane-2,4,6,8-tetracarboxylic acid dianhydride

CBDA: 1,2,3,4-Cyclobutane tetracarboxylic acid dianhydride

PMDA: pyromellitic acid dianhydride

TCA: 2,3,5-tricarboxycyclopentyl acetic acid-1,4,2,3-2 anhydride

(Diamine)

p-PDA: p-phenylenediamine

DBA: 3,5-diaminobenzoic acid

3AMPDA: 3,5-diamino-N- (pyridin-3-ylmethyl) benzamide

The photosensitive diamines represented by the following formulas DA-1 to DA-3

(50)

The polymerizable diamine represented by the following formula DA-4

(51)

Vertically-oriented side chain diamines represented by the following formulas DA-5 to DA-7

(52)

Diamines represented by the following formulas DA-8 to DA-9

(53)

<Solvent>

NMP: N-methyl-2-pyrrolidone

BCS: butyl cellosolve

<Additives>

3AMP: 3-Picolylamine

<Polymerizable compound>

The polymerizable compound represented by the following formula RM1

(54)

The conditions for measuring the molecular weight of the polyimide are as follows.

Apparatus: Room temperature gel permeation chromatography (GPC) apparatus (SSC-7200) manufactured by Senshu Scientific Co.,

Column: Column (KD-803, KD-805) manufactured by Shodex Co.,

Column temperature: 50 ° C

30 mmol / l of lithium bromide-hydrate (LiBr.H ₂ O), 30 mmol / l of phosphoric acid-anhydrous crystals (o-phosphoric acid) as an additive, 30 mmol / l of N, N'-dimethylformamide (tetrahydrofuran ) &Lt; / RTI &gt; 10 ml / l)

Flow rate: 1.0 ml / min

Standard sample for preparing calibration curve: TSK standard polyethylene oxide (molecular weight: about 9,000,000, 150,000, 100,000, 30,000) manufactured by Tosoh Corporation and polyethylene glycol (molecular weight about 12,000, 4,000, 1,000) manufactured by Polymer Laboratories.

The imidization rate of the polyimide was measured as follows. 20 mg of the polyimide powder was placed in an NMR sample tube (NMR sampling tube standard φ5 manufactured by Kusano Scientific Co., Ltd.), 1.0 ml of deuterated dimethyl sulfoxide (DMSO-d ₆ , 0.05% TMS mixture) was added, . This solution was subjected to proton NMR measurement at 500 MHz using an NMR measuring instrument (JNW-ECA500) manufactured by Nippon Dental Electronics. The rate of imidization is determined as a reference proton derived from a structure that does not change before and after imidization, and the peak integrated value of the proton and the total amount of proton peaks derived from the NH group of the amic acid appearing in the vicinity of 9.5 to 10.0 ppm Value was obtained by the following formula. In the following formula, x is the proton peak integrated value derived from the NH group of the amic acid, y is the peak integrated value of the reference proton, and? Is the NH of the amic acid when the polyamic acid (imidation rate is 0%) Is the ratio of the number of reference protons to one proton of the group.

Imidization ratio (%) = (1 -? X / y) x 100

(Synthesis Example 1)

(13.22 g, 40.0 mmol) and DA-5 (15.22 g, 40.0 mmol) were dissolved in NMP (164.6 g) and treated with 60 C for 5 hours, CBDA (11.57 g, 59.0 mmol) and NMP (54.9 g) were added and reacted at 40 ° C for 10 hours to obtain a polyamic acid solution.

NMP was added to the polyamic acid solution (250 g) to dilute it to 6.5 mass%, acetic anhydride (46.4 g) and pyridine (14.4 g) were added as imidation catalysts and reacted at 70 ° C for 3 hours. The reaction solution was poured into methanol (3300 ml), and the resulting precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C to obtain a polyimide powder (A). The imidization rate of the polyimide was 72%, the number average molecular weight was 14,000, and the weight average molecular weight was 38000.

NMP (44.0 g) was added to the obtained polyimide powder (A) (6.0 g), and the mixture was stirred and dissolved at 70 占 폚 for 20 hours. 6.0 g of 3AMP (1 mass% NMP solution), 4.0 g of NMP and 40.0 g of BCS were added to this solution and stirred at room temperature for 5 hours to obtain liquid crystal aligning agent (U1).

(Synthesis Example 2)

DA-5 (15.22 g, 40.0 mmol) was dissolved in NMP (168.0 g) and treated with 60 (10.01 g, 40.0 mmol) After reacting for 5 hours at room temperature, CBDA (11.57 g, 59.0 mmol) and NMP (55.98 g) were added and reacted at 40 ° C for 10 hours to obtain a polyamic acid solution.

NMP was added to the polyamic acid solution (250 g) to dilute it to 6.5 mass%, acetic anhydride (45.4 g) and pyridine (14.0 g) were added as imidation catalysts and reacted at 70 ° C for 3 hours. The reaction solution was poured into methanol (3300 ml), and the resulting precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C to obtain a polyimide powder (B). The imidization ratio of the polyimide was 73%, the number average molecular weight was 18,000, and the weight average molecular weight was 37000.

NMP (44.0 g) was added to the obtained polyimide powder (B) (6.0 g), and the mixture was stirred and dissolved at 70 占 폚 for 20 hours. 6.0 g of 3AMP (1 mass% NMP solution), 4.0 g of NMP and 40.0 g of BCS were added to this solution and stirred at room temperature for 5 hours to obtain liquid crystal aligning agent (U2).

(Synthesis Example 3)

3 (13.78 g, 40.0 mmol), DA-5 (15.22 g, 40.0 mmol) was dissolved in NMP (166.2 g) and a solution of 60 (10.01 g, 40.0 mmol) After reacting for 5 hours at room temperature, CBDA (11.57 g, 59.0 mmol) and NMP (55.42 g) were added and reacted at 40 ° C for 10 hours to obtain a polyamic acid solution.

NMP was added to the polyamic acid solution (250 g) to dilute it to 6.5 mass%, acetic anhydride (45.49 g) and pyridine (14.3 g) as an imidation catalyst were added and reacted at 70 ° C for 3 hours. The reaction solution was poured into methanol (3300 ml), and the resulting precipitate was separated by filtration. The precipitate was washed with methanol, and dried at 100 ° C under reduced pressure to obtain a polyimide powder (C). The polyimide had an imidization rate of 72%, a number average molecular weight of 21,000, and a weight average molecular weight of 82,000.

NMP (44.0 g) was added to the obtained polyimide powder (C) (6.0 g), and the mixture was stirred and dissolved at 70 占 폚 for 20 hours. To this solution, 6.0 g of 3AMP (1 mass% NMP solution), 4.0 g of NMP (40.0 g) and BCS were added and stirred at room temperature for 5 hours to obtain liquid crystal aligning agent (U3).

(Synthesis Example 4)

5 (7.61 g, 20.0 mmol), DA-7 (9.90 g, 20.0 mmol), TCA (11.21 g, 50.0 mmol), p-PDA (4.33 g, 40.0 mmol) (9.61 g, 49.0 mmol) and NMP (49.54 g) were added to the reaction mixture and reacted at 40 ° C for 10 hours to obtain a polyamic acid solution. .

NMP was added to the polyamic acid solution (220 g) to dilute it to 6.5 mass%, acetic anhydride (35.1 g) and pyridine (10.9 g) as an imidation catalyst were added and reacted at 50 ° C for 3 hours. The reaction solution was poured into methanol (2900 ml), and the resulting precipitate was separated by filtration. The precipitate was washed with methanol, and dried at 100 ° C under reduced pressure to obtain a polyimide powder (D). The imidization ratio of the polyimide was 51%, the number average molecular weight was 11000, and the weight average molecular weight was 25,000.

NMP (44.0 g) was added to the obtained polyimide powder (D) (6.0 g), and the mixture was stirred and dissolved at 70 占 폚 for 20 hours. To this solution, 6.0 g of 3AMP (1 mass% NMP solution), 4.0 g of NMP (40.0 g) and BCS were added and stirred at room temperature for 5 hours to obtain liquid crystal aligning agent (U4).

(Synthesis Example 5)

5 (7.61 g, 20.0 mmol), DA-6 (8.69 g, 20.0 mmol), DA-4 (7.93 g, 30.0 mmol), DA-3 (10.33 g, 30.0 mmol) (11.57 g, 49.0 mmol) and NMP (56.14 g) were added and reacted at 40 ° C for 10 hours to obtain a polyamic acid solution. The resulting solution was reacted at 80 ° C for 5 hours, .

NMP was added to the polyamic acid solution (250 g) to dilute it to 6.5 mass%, acetic anhydride (27.2 g) and pyridine (70.2 g) were added as imidation catalysts and reacted at 50 ° C for 3 hours. The reaction solution was poured into methanol (3500 ml), and the resulting precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C to obtain a polyimide powder (E). The imidization ratio of the polyimide was 59%, the number average molecular weight was 14,000, and the weight average molecular weight was 51,000.

NMP (44.0 g) was added to the obtained polyimide powder (E) (6.0 g), and the mixture was stirred and dissolved at 70 占 폚 for 20 hours. 6.0 g of 3AMP (1 mass% NMP solution), 4.0 g of NMP and 40.0 g of BCS were added to this solution and stirred at room temperature for 5 hours to obtain liquid crystal aligning agent (U5).

(Synthesis Example 6)

DA-5 (11.42 g, 30.0 mmol) was dissolved in NMP (143.7 g), and DA-8 (9.96 g, After reacting for 5 hours at room temperature, CBDA (4.12 g, 21.0 mmol) and NMP (47.89 g) were added and reacted at 40 ° C for 10 hours to obtain a polyamic acid solution.

NMP was added to the polyamic acid solution (180 g) to dilute it to 6.5 mass%, acetic anhydride (19.1 g) and pyridine (14.8 g) were added as imidation catalysts and reacted at 80 ° C for 4 hours. The reaction solution was poured into methanol (2200 ml), and the resulting precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C to obtain a polyimide powder (E). The imidization ratio of the polyimide was 57%, the number average molecular weight was 12,000, and the weight average molecular weight was 39000.

NMP (44.0 g) was added to the obtained polyimide powder (E) (6.0 g), and the mixture was stirred and dissolved at 70 占 폚 for 20 hours. 6.0 g of 3AMP (1 mass% NMP solution), 4.0 g of NMP and 40.0 g of BCS were added to this solution and stirred at room temperature for 5 hours to obtain a liquid crystal aligning agent (L1).

(Synthesis Example 7)

(12.51 g, 50.0 mmol), DBA (12.93 g, 85.0 mmol) and DA-9 (6.16 g, 15.0 mmol) were dissolved in NMP (123.3 g) and reacted at 60 ° C for 3 hours. CBDA g, 48.5 mmol) and NMP (41.11 g) were added and reacted at 40 ° C for 10 hours to obtain a polyamic acid solution.

NMP was added to the polyamic acid solution (180 g) to dilute it to 6.5 mass%, acetic anhydride (44.4 g) and pyridine (13.8 g) were added as imidation catalysts and reacted at 80 ° C for 2 hours. The reaction solution was poured into methanol (2400 ml), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried under reduced pressure at 100 ° C to obtain a polyimide powder (F). The imidization ratio of the polyimide was 70%, the number average molecular weight was 12,000, and the weight average molecular weight was 31,000.

NMP (44.0 g) was added to the resulting polyimide powder (F) (6.0 g), and the mixture was stirred and dissolved at 70 占 폚 for 20 hours. 6.0 g of 3AMP (1 mass% NMP solution), 4.0 g of NMP and 40.0 g of BCS were added to this solution and stirred at room temperature for 5 hours to obtain a liquid crystal aligning agent L2.

(Synthesis Example 8)

5 (11.42 g, 30.0 mmol) was dissolved in NMP (136.5 g) at 60 ° C and the mixture was stirred at room temperature for 3 hours. After reacting for 3 hours, PMDA (4.36 g, 48.5 mmol), CBDA (11.37 g, 58.0 mmol) and NMP (45.51 g) were added and reacted at 40 ° C for 10 hours to obtain a polyamic acid solution.

NMP was added to the polyamic acid solution (180 g) to dilute it to 6.5 mass%, acetic anhydride (40.0 g) and pyridine (12.4 g) were added as an imidization catalyst and reacted at 50 ° C for 3 hours. The reaction solution was poured into methanol (2300 ml), and the resulting precipitate was separated by filtration. The precipitate was washed with methanol, and dried at 100 ° C under reduced pressure to obtain a polyimide powder (G). The imidization ratio of the polyimide was 78%, the number average molecular weight was 9000, and the weight average molecular weight was 20,000.

NMP (44.0 g) was added to the obtained polyimide powder (G) (6.0 g), and the mixture was stirred and dissolved at 70 캜 for 20 hours. 6.0 g of 3AMP (1 mass% NMP solution), 4.0 g of NMP and 40.0 g of BCS were added to this solution and stirred at room temperature for 5 hours to obtain a liquid crystal aligning agent (L3).

(Example 1)

3.0 g of the liquid crystal aligning agent (U1) obtained in Synthesis Example 1 as a first component and 7.0 g of the liquid crystal aligning agent (L1) obtained in Example 5 as a second component were mixed and stirred for 1 hour to obtain a liquid crystal aligning agent A1 ) Was prepared.

&Lt; Production of liquid crystal cell &

Using the liquid crystal aligning agent (A1) obtained in Example 1, a liquid crystal cell was produced in the following order. The liquid crystal aligning agent A1 obtained in Example 1 was spin-coated on the ITO surface of the ITO electrode substrate on which ITO electrode patterns having a pixel size of 100 mu m x 300 mu m and a line / space of 5 mu m were formed, , And then fired in a hot-air circulating oven at 200 캜 for 30 minutes to form a liquid crystal alignment film having a thickness of 100 nm.

The liquid crystal aligning agent A1 was spin-coated on an ITO surface on which no electrode pattern was formed, dried for 90 seconds on a hot plate at 80 占 폚 and fired in a hot air circulating oven at 200 占 폚 for 30 minutes, A liquid crystal alignment film having a thickness of 100 nm was formed.

A bead spacer of 4 mu m was dispersed on the liquid crystal alignment film of one of the two substrates, and then a sealant (solvent type thermosetting type epoxy resin) was printed thereon. Subsequently, the other side of the substrate on the side where the liquid crystal alignment film was formed was inwardly joined with the above-mentioned substrate, and then the sealing agent was cured to prepare empty cells. A liquid crystal MLC-3023 (trade name, manufactured by Merck & Co., Inc.) containing a polymerizable compound for PSA was injected into this empty cell by a low pressure injection method to prepare a liquid crystal cell.

The response speed of the obtained liquid crystal cell was measured by the following method. Thereafter, in a state in which a DC voltage of 15 V was applied to the liquid crystal cell, UV light having passed through a 365 nm band-pass filter was irradiated from the outside of the liquid crystal cell at 10 J / cm2. The UV illuminance was measured using UV-MO3A manufactured by ORC. Thereafter, in order to deactivate the unreacted polymerizable compound remaining in the liquid crystal cell, the UV (FL lamp: FLR40SUV32 / A-1) was irradiated using a UV-FL irradiation apparatus manufactured by Toshiba Litech Co., 1) for 30 minutes. Thereafter, the response speed was again measured, and the response speeds before and after the UV irradiation were compared. Further, the pretilt angle of the pixel portion was measured with respect to the cell after UV irradiation.

The residual DC voltage of each cell was measured. The results are shown in the table.

How to measure the response speed

First, a liquid crystal cell was disposed between a set of polarizers in a measuring apparatus comprising a pair of polarizers in the state of backlight, Cross-Nicol, and a light quantity detector in this order. At this time, the pattern of the ITO electrode in which the line / space was formed was made to have an angle of 45 degrees with respect to Cross-Nicol. Then, a rectangular wave having a voltage of + 7 V and a frequency of 1 kHz is applied to the liquid crystal cell, and the change until the luminance observed by the light amount detector is saturated is acquired by an oscilloscope. The luminance when the voltage is not applied is 0%, and a voltage of ± 6 V was applied. The time taken for the luminance to change from 10% to 90% was taken as the response speed with the saturation luminance value as 100%.

&Quot; Measurement of the pretilt angle &quot;

LC analyzer LCA-LUV42A manufactured by Meier Technology Co., Ltd. was used.

&Quot; Evaluation of residual DC voltage &quot;

A rectangular wave of 30 Hz and 7.8 Vpp superimposed with DC 2 V was applied to the liquid crystal cell prepared above at 23 DEG C for 100 hours, and the voltage (residual DC voltage) remaining in the liquid crystal cell immediately after the DC voltage was cut off was applied to the liquid crystal cell Lt; / RTI &gt; This value is an indicator of residual image caused by DC accumulation. When this value is approximately 30 mV or less, it is determined that the afterimage characteristic is excellent.

(Example 2)

A liquid crystal aligning agent (A2) was prepared in the same manner as in Example 1 except that the liquid crystal aligning agent (L1) was a liquid crystal aligning agent (L2). The same operation as in Example 1 was carried out to measure the response speed, the pretilt angle, and the residual DC voltage.

(Example 3)

A liquid crystal aligning agent (A3) was prepared in the same manner as in Example 1 except that the liquid crystal aligning agent (L1) was a liquid crystal aligning agent (L3). The same operation as in Example 1 was carried out to measure the response speed, the pretilt angle, and the residual DC voltage.

(Example 4)

A liquid crystal aligning agent (A4) was prepared in the same manner as in Example 1 except that the liquid crystal aligning agent (U1) was a liquid crystal aligning agent (U2). The same operation as in Example 1 was carried out to measure the response speed, the pretilt angle, and the residual DC voltage.

(Example 5)

A liquid crystal aligning agent (A5) was prepared in the same manner as in Example 4 except that the liquid crystal aligning agent (L1) was a liquid crystal aligning agent (L2). The same operation as in Example 1 was carried out to measure the response speed, the pretilt angle, and the residual DC voltage.

(Example 6)

A liquid crystal aligning agent (A6) was prepared in the same manner as in Example 4 except that the liquid crystal aligning agent (L1) was a liquid crystal aligning agent (L3). The same operation as in Example 1 was carried out to measure the response speed, the pretilt angle, and the residual DC voltage.

(Example 7)

A liquid crystal aligning agent (A7) was prepared in the same manner as in Example 1 except that the liquid crystal aligning agent (U1) was changed to the liquid crystal aligning agent (U3). The same operation as in Example 1 was carried out to measure the response speed, the pretilt angle, and the residual DC voltage.

(Example 8)

A liquid crystal aligning agent (A8) was prepared in the same manner as in Example 7 except that the liquid crystal aligning agent (L1) was a liquid crystal aligning agent (L2). The same operation as in Example 1 was carried out to measure the response speed, the pretilt angle, and the residual DC voltage.

(Example 9)

A liquid crystal aligning agent (A9) was prepared in the same manner as in Example 7 except that the liquid crystal aligning agent (L1) was a liquid crystal aligning agent (L3). The same operation as in Example 1 was carried out to measure the response speed, the pretilt angle, and the residual DC voltage.

(Example 10)

A liquid crystal aligning agent (A10) was prepared in the same manner as in Example 1 except that the liquid crystal aligning agent (U1) was a liquid crystal aligning agent (U4). The same operation as in Example 1 was carried out to measure the response speed, the pretilt angle, and the residual DC voltage.

(Example 11)

A liquid crystal aligning agent (A11) was prepared in the same manner as in Example 10 except that the liquid crystal aligning agent (L1) was a liquid crystal aligning agent (L2). The same operation as in Example 1 was carried out to measure the response speed, the pretilt angle, and the residual DC voltage.

(Example 12)

A liquid crystal aligning agent (A12) was prepared in the same manner as in Example 10 except that the liquid crystal aligning agent (L1) was a liquid crystal aligning agent (L3). The same operation as in Example 1 was carried out to measure the response speed, the pretilt angle, and the residual DC voltage.

(Example 13)

A liquid crystal aligning agent (A13) was prepared in the same manner as in Example 1 except that the liquid crystal aligning agent (U1) was a liquid crystal aligning agent (U5). The same operation as in Example 1 was carried out to measure the response speed, the pretilt angle, and the residual DC voltage.

(Example 14)

A liquid crystal aligning agent (A14) was prepared in the same manner as in Example 13 except that the liquid crystal aligning agent (L1) was a liquid crystal aligning agent (L2). The same operation as in Example 1 was carried out to measure the response speed, the pretilt angle, and the residual DC voltage.

(Example 15)

A liquid crystal aligning agent (A15) was prepared in the same manner as in Example 13 except that the liquid crystal aligning agent (L1) was changed to the liquid crystal aligning agent (L3). The same operation as in Example 1 was carried out to measure the response speed, the pretilt angle, and the residual DC voltage.

(Example 16)

, 5.0 g of the liquid crystal aligning agent (U5) as the first component, 5.0 g of the liquid crystal aligning agent (L1) as the second component and 0.06 g of the polymerizable compound (10% by mass based on the solid content of the liquid crystal aligning agent) And stirred for 1 hour to prepare a liquid crystal aligning agent (A16). The same operation as in Example 1 was carried out except that MLC-6608 was used as a liquid crystal containing no PSA polymerizable compound to measure the response speed, the pretilt angle, and the residual DC voltage.

(Comparative Example 1)

The same operation as in Example 1 was carried out except that the liquid crystal aligning agent (U1) was used as the liquid crystal aligning agent, and the response speed, the pretilt angle and the residual DC voltage were measured.

(Comparative Example 2)

The same operation as in Example 1 was performed except that the liquid crystal aligning agent (U2) was used as the liquid crystal aligning agent, and the response speed, the pretilt angle, and the residual DC voltage were measured.

(Comparative Example 3)

The same operation as in Example 1 was carried out except that the liquid crystal aligning agent (U3) was used as the liquid crystal aligning agent, and the response speed, the pretilt angle and the residual DC voltage were measured.

(Comparative Example 4)

The same operation as in Example 1 was carried out except that the liquid crystal aligning agent (U4) was used as the liquid crystal aligning agent, and the response speed, the pretilt angle and the residual DC voltage were measured.

(Comparative Example 5)

The same operation as in Example 1 was carried out except that the liquid crystal aligning agent (U5) was used as the liquid crystal aligning agent, and the response speed, the pretilt angle and the residual DC voltage were measured.

As shown in the results, in Examples 1 to 12, by introducing Component 1 having a radical generating structure, it was found that the tilt angle was given by UV irradiation and the response speed was improved. In addition, the residual DC voltage characteristic is also good, and it can be seen that almost no residual DC voltage is accumulated even after long-time DC application.

On the other hand, since the component 2 was not introduced in the comparative example, it was confirmed that the residual DC voltage was accumulated by the application of the DC for a long time.

As described above, by using the first component having the radical generating structure and the second component having the effect of suppressing the residual DC voltage in combination, it is possible to improve the response speed even with ultraviolet irradiation of a long wavelength (for example, 365 nm) It is possible to provide such an excellent liquid crystal display element.

Claims (4)

A liquid crystal aligning agent characterized by comprising the following components (A), (B) and an organic solvent.
Component (A): A polyimide precursor having side chains for vertically orienting liquid crystals and side chains having sites for generating radicals by ultraviolet irradiation shown by the following formula (1), and polyimide precursors At least one kind of polymer selected from the polyimide obtained.
[Chemical Formula 1]

R ₁ and R ₂ are each independently an alkyl group or an alkoxy group having 1 to 10 carbon atoms, and each of T 1 and T 2 is independently a single bond or -O-, -COO-, -OCO-, -NHCO-, -CONH -, -NH-, -CH ₂ O-, -N (CH ₃ ) -, -CON (CH ₃ ) -, -N (CH ₃ ) CO- and S is a single bond or an unsubstituted or fluorine atom An alkylene group having 1 to 20 carbon atoms, The -CH ₂ - or -CF ₂ - of the mono-alkylene group may be optionally substituted with -CH = CH-, and in the case where any of the groups shown below are not adjacent to each other, these groups may be substituted; -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbon ring, a divalent heterocyclic ring, and Q represents a structure selected from the following.
(2)

And R is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.
(B): a polyimide precursor obtained by using as a raw material a diamine component containing at least one diamine selected from the following formulas (B-1) to (B-5), and a polyimide precursor obtained by imidizing the polyimide precursor A polyimide precursor obtained by using as a raw material a tetracarboxylic acid dianhydride component containing a polymer selected from polyimide or at least one tetracarboxylic acid dianhydride selected from the following formulas (3) and (4), and A polymer selected from polyimides obtained by imidizing the polyimide precursor.
(3)

Y ₁ is a monovalent organic group having a secondary amine, a tertiary amine or a heterocyclic structure, and Y ₂ is a divalent organic group having a secondary amine, a tertiary amine or a heterocyclic structure.
[Chemical Formula 4]

n, m is 0 or 1, and X and y are a single bond, a carbonyl, an ester, a phenylene, or a sulfonyl group. A liquid crystal alignment film obtained by applying the liquid crystal aligning agent according to claim 1 to a substrate and firing. A liquid crystal display device characterized by comprising a liquid crystal cell comprising a liquid crystal alignment layer according to any one of claims 1 to 3 and a liquid crystal alignment layer obtained by applying and firing the liquid crystal alignment layer to a substrate to form a liquid crystal layer, device. A liquid crystal cell is produced by irradiating ultraviolet rays while applying a voltage to the liquid crystal layer by contacting the liquid crystal alignment layer obtained by applying the liquid crystal aligning agent according to claim 1 to a substrate and firing the liquid crystal alignment layer. / RTI &gt;