TW201811869A - Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element - Google Patents

Abstract

Provided are: a liquid crystal alignment agent which can enhance the adhesion between a sealant and a liquid crystal alignment film and suppress the occurrence of display unevenness in the vicinity of the frame of a liquid crystal display element even under high temperature and high humidity conditions, and which at times is used for mobile devices; a liquid crystal alignment film; and a liquid crystal display element. The liquid crystal alignment agent is characterized by containing components (A) and (B) below and an organic solvent. Component (A): a polymer having the ability to form a polymer film and align liquid crystals by alignment treatment. Component (B): a compound having an aliphatic skeleton and having three or more epoxy groups.

Description

   Liquid crystal alignment agent, liquid crystal alignment film and liquid crystal display element   

The present invention relates to a liquid crystal alignment agent for manufacturing a liquid crystal display element, a liquid crystal alignment film obtained from the liquid crystal alignment agent, and a liquid crystal display element using the liquid crystal alignment film.

Liquid crystal display elements are known as light-weight, thin, and low-power display devices. In recent years, high-definition liquid crystal display elements for smart phones or tablet-type terminals that have rapidly expanded their market share have also demanded amazing development of high display quality.

A liquid crystal display element is composed of a pair of transparent substrates with electrodes and a liquid crystal layer. However, an organic film made of an organic material is used as a liquid crystal alignment film, so that the liquid crystal becomes a desired alignment state between the substrates. That is, in the liquid crystal display element, the liquid crystal alignment film is formed on the surface where the substrate holding the liquid crystal contacts the liquid crystal, and plays a role of aligning the liquid crystal in a certain direction between the substrates. In addition, the pretilt angle of the liquid crystal can be controlled by the liquid crystal alignment film, and a method of increasing the pretilt angle (see Patent Document 1) and a method of lowering (see Patent Document 2) are mainly selected by selecting a polyimide structure.

In addition, a liquid crystal display device (VA method) in which a liquid crystal molecule is vertically aligned with a substrate by an electric field (VA method) includes a step of irradiating ultraviolet rays while applying a voltage to the liquid crystal molecules in a manufacturing process.

This VA-type liquid crystal display element is a liquid crystal composition in which a photopolymerizable compound is added in advance, and a vertical alignment film such as polyimide is used. The liquid crystal is enhanced by applying a voltage to the liquid crystal cell while irradiating ultraviolet rays. The response speed PSA (Polymer Sustained Alignment) system element is known (see Patent Document 3 and Non-Patent Document 1).

    [Prior technical literature]         [Patent Literature]    

[Patent Document 1] Japanese Patent Laid-Open No. 09-278724

[Patent Document 2] Japanese Patent Application Laid-Open No. 10-123532

[Patent Document 3] Japanese Patent Laid-Open No. 2003-307720

    [Non-patent literature]    

[Non-Patent Document 1] K. Hanaoka, SID 04 DIGEST, P.1200-1202

    [Invention of Invention]    

In recent years, in order to ensure as large a display surface as possible for a portable device such as a smart phone or a mobile phone, the width of the sealant for indirect application of the substrate of the liquid crystal display element is narrower than in the past, so-called narrow frame. With the narrow bezel of this panel, the application position of the sealant used in the production of the liquid crystal display element is the position where it is in contact with the end of the liquid crystal alignment film or the upper part of the liquid crystal alignment film. Since imines have no polar groups or are few, covalent bonds are not formed on the surface of the sealant and the liquid crystal alignment film, and there is a problem that the substrates are insufficiently adhered to each other.

As described above, especially when used under high-temperature and high-humidity conditions, water is easily mixed between the sealant and the liquid crystal alignment film, and the problem of display unevenness occurs near the frame of the liquid crystal display element. Therefore, it is a problem to improve the adhesion (adhesion) between the polyfluorene-based liquid crystal alignment film and the sealant or the substrate. As described above, the improvement of the adhesion between the liquid crystal alignment film and the sealant or the substrate must be achieved without lowering the liquid crystal alignment or the electrical characteristics of the liquid crystal alignment film. In addition, it is required to improve these characteristics.

As a result of careful review by the inventors, it was found that a liquid crystal alignment agent containing the following components (A), (B) and an organic solvent can achieve the above-mentioned problems, and completed the present invention.

(A) Component: A polymer that forms a polymer film and has the ability to align liquid crystals by alignment treatment

(B) Component: A compound having an aliphatic skeleton and having three or more epoxy groups.

By using the liquid crystal alignment agent of the present invention, the above-mentioned problems can be achieved without lowering the liquid crystal alignment or electrical characteristics. That is, by using the liquid crystal alignment agent of the present invention, it is possible to improve the adhesion between the sealant and the liquid crystal alignment film, and to suppress the occurrence of display unevenness near the frame of the liquid crystal display element under high temperature and high humidity conditions. membrane. Therefore, the liquid crystal display element having the liquid crystal alignment film can improve the adhesion between the sealant and the liquid crystal alignment film, can solve the display unevenness near the frame, and is suitable for large-screen and high-definition liquid crystal displays, especially for portable liquid crystal displays. .

     [Form of Implementing Invention]           <(A) component>     

The polymer of the component (A) contained in the liquid crystal alignment agent of the present invention is not particularly limited as long as it is a polymer film that has the ability to align liquid crystals by alignment treatment. Examples include polyamic acid and polyamidate (the following two are also referred to as polyimide precursors), polyimide of polyimide, polyurea, polyurea, Polysiloxane, polyamidoamine, polyamidoimide, (meth) acrylate, and the like. Among them, polyimide of polyimide precursor and / or polyimide of polyimide precursor is preferred.

The polyimide precursor suitable for the polymer used in the liquid crystal alignment agent of the present invention has a structural unit represented by the following formula (1).

In the formula (1), X ₁ is a tetravalent organic group, and Y ₁ is a divalent organic group. R ₁ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and A ₁ and A ₂ are each independently a hydrogen atom or an alkyl group having 1 to 10 carbon atoms and an alkenyl group having 2 to 10 carbon atoms which may have a substituent Or an alkynyl group having 2 to 10 carbon atoms.

Specific examples of the alkyl group in R ₁ include methyl, ethyl, propyl, i-propyl, n-butyl, i-butyl, s-butyl, t-butyl, and n-pentyl. Base etc. From the viewpoint of being easily imidized by heating, R ₁ is a hydrogen atom or a methyl group.

In the formula (1), X ₁ is a tetravalent organic group derived from a tetracarboxylic acid derivative, and its structure is not particularly limited. In the polyimide precursor, X ₁ may be mixed in two or more kinds. Specific examples of X ₁ include structures of the following formulae (X-1) to (X-44).

R ₈ to R ₁₁ in the formula (X-1) are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group, or a phenyl group. When R ₈ to R _{11 have} a large-volume structure, the alignment of the liquid crystal may be reduced. Therefore, a hydrogen atom, a methyl group, and an ethyl group are more preferable, and a hydrogen atom or a methyl group is particularly preferable.

In the formula (1), X ₁ preferably contains a structure selected from (X-1) to (X-14) from the viewpoint of the availability of the monomer.

The reliability of the obtained liquid crystal alignment film can be further improved, so the structure of X ₁ such as the alicyclic structure of (X-1) ~ (X-7) and (X-10) is better, (X-1) represents Better structure. In addition, in order to display good liquid crystal alignment, the structure of X ₁ is more preferably the following formula (X1-1) or (X1-2).

A preferred ratio of the structure selected from the above (X-1) to (X-44) is 20 mol% or more, more preferably 60 mol% or more, and more preferably 80 mol% or more of X _{1 as a} whole. .

In Formula (1), A ₁ and A ₂ are each independently a hydrogen atom, or an alkyl group having 1 to 10 carbons which may have a substituent, an alkenyl group having 2 to 10 carbons which may have a substituent, and may have a substituent An alkynyl group having 2 to 10 carbon atoms.

Specific examples of the alkyl group include methyl, ethyl, propyl, butyl, t-butyl, hexyl, octyl, decyl, cyclopentyl, cyclohexyl, and dicyclohexyl. Examples of the alkenyl group include those in which at least one CH-CH structure existing in the alkyl group is substituted with a C = C structure, and more specifically, vinyl, allyl, 1-propenyl, and isopropenyl , 2-butenyl, 1,3-butadienyl, 2-pentenyl, 2-hexenyl, cyclopropenyl, cyclopentenyl, cyclohexenyl, and the like. Examples of the alkynyl group include those in which one or more CH ₂ -CH ₂ structures existing in the alkyl group are substituted with a C≡C structure. More specifically, ethynyl, 1-propynyl, and 2-propyne Base etc.

The above-mentioned alkyl group, alkenyl group, and alkynyl group may have a substituent, and may further form a ring structure through a substituent. In addition, the formation of a ring structure by a substituent means that the substituents are bonded to each other or a part of the substituent and a part of the parent skeleton to form a ring structure.

Examples of the substituent include a halogen group, a hydroxyl group, a mercapto group, a nitro group, an aryl group, an organoxy group, an organothio group, an organosilyl group, a fluorenyl group, an ester group, and a sulfur group. Esters, phosphates, amido, alkyl, alkenyl, alkynyl and the like.

Examples of the halogen group of the substituent include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

Examples of the aryl group of the substituent include a phenyl group. This aryl group may be further substituted with the aforementioned other substituents.

The organic oxy group of the substituent may represent a structure represented by -O-R. This R may be the same or different, and examples thereof include the aforementioned alkyl, alkenyl, alkynyl, and aryl groups. These R may be further substituted with the aforementioned substituents. Specific examples of the organic oxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentyloxy group, a hexyloxy group, a heptyloxy group, and an octyloxy group.

The organic thio group of the substituent may represent a structure represented by -S-R. Examples of this R include the aforementioned alkyl, alkenyl, alkynyl, and aryl groups. These R may be further substituted with the aforementioned substituents. Specific examples of the organic thio group include methylthio, ethylthio, propylthio, butylthio, pentylthio, hexylthio, heptylthio, and octylthio.

The substituted organosilyl group may have a structure represented by -S1- (R) ₃ . This R may be the same or different, and examples thereof include the aforementioned alkyl, alkenyl, alkynyl, and aryl groups. These R may be further substituted with the aforementioned substituents. Specific examples of the organosilyl group include trimethylsilyl, triethylsilyl, tripropylsilyl, tributylsilyl, tripentylsilyl, trihexylsilyl, and pentyl. Dimethylsilyl, hexyldimethylsilyl and the like.

The fluorenyl group of the substituent may represent a structure represented by -C (O) -R. Examples of R include the aforementioned alkyl, alkenyl, and aryl groups. These R may be further substituted with the aforementioned substituents. Specific examples of the fluorenyl group include methyl fluorenyl, acetyl fluorenyl, propyl fluorenyl, butyl fluorenyl, isobutyl fluorenyl, pentyl fluorenyl, isopentyl fluorenyl, benzyl fluorenyl and the like.

The ester group of the substituent may represent a structure represented by -C (O) O-R or -OC (O) -R. Examples of this R include the aforementioned alkyl, alkenyl, alkynyl, and aryl groups. These R may be further substituted with the aforementioned substituents.

The thioester group of the substituent may represent a structure represented by -C (S) O-R or -OC (S) -R. Examples of this R include the aforementioned alkyl, alkenyl, alkynyl, and aryl groups. These R may be further substituted with the aforementioned substituents.

The phosphate group of the substituent may represent a structure represented by -OP (O)-(OR) ₂ . This R may be the same or different, and examples thereof include the aforementioned alkyl, alkenyl, alkynyl, and aryl groups. These R may be further substituted with the aforementioned substituents.

The amido group of the substituent may be represented by -C (O) NH ₂ or -C (O) NHR, -NHC (O) R, -C (O) N (R) ₂ , -NRC (O) R Structure. This R may be the same or different, and examples thereof include the aforementioned alkyl, alkenyl, alkynyl, and aryl groups. These R may be further substituted with the aforementioned substituents.

The aryl group of the substituent may be the same as the aryl group described above. This aryl group may be further substituted with the other substituents described above.

The alkyl group of the substituent may be the same as the alkyl group described above. This alkyl group may be further substituted with the other substituents described above.

Examples of the alkenyl group as the substituent include the same as the alkenyl group described above. This alkenyl group may be further substituted with the other substituents described above.

Examples of the alkynyl group as the substituent are the same as those described above. This alkynyl group may be further substituted with the other substituents described above.

Generally, if a bulky structure is introduced, the reactivity of the amine group or the alignment of the liquid crystal may be reduced. Therefore, A ₁ and A _{2 are more} preferably a hydrogen atom or an alkyl group having 1 to 5 carbon atoms which may have a substituent. Particularly preferred is a hydrogen atom, a methyl group or an ethyl group.

In the formula (1), Y ₁ is a divalent organic group derived from a diamine, and its structure is not particularly limited. The diamine is represented by the following formula, and when a specific example of the structure of Y ₁ is shown, the following Y-1 to Y-194 may be mentioned.

In the formula, n is an integer from 1 to 6.

Boc in the above formula represents a third butoxycarbonyl group.

(In formula (Y-192), m and n are each independently an integer of 1 to 11; m + n is an integer of 2 to 12; in formulas (Y-193) and (Y-194), j is 0 to 3 Integer).

From the viewpoint of liquid crystal alignment or pretilt angle of the obtained liquid crystal alignment film, Y ₁ is more preferably at least one selected from the structures represented by the following formulae (5) and (6).

In formula (5), R ₁₂ is a single bond or a divalent organic group having 1 to 30 carbon atoms, R ₁₃ is a hydrogen atom, a halogen atom, or a monovalent organic group having 1 to 30 carbon atoms, and a is 1 to 4 When an integer is 2 or more, R ₁₂ and R ₁₃ may be the same or different from each other.

In formula (6), R ₁₄ is a single bond, -O-, -S-, -NR _15- , amine bond, ester bond, urea bond, or a divalent organic group having 1 to 40 carbon atoms, and R ₁₅ is Hydrogen atom or methyl.

Specific examples of the formulas (5) and (6) include the following structures.

The structure with high linearity can improve the alignment of the liquid crystal when used as a liquid crystal alignment film, so Y ₁ is more preferably Y-7, Y-21, Y-22, Y-23, Y-25, Y-43, Y-44, Y-45, Y-46, Y-48, Y-54, Y-62, Y-63, Y-64, Y-65, Y-66, Y-67, or Y-160. The above-described configuration can increase the ratio of liquid crystal alignment property, the more preferred Y ₁ 20 mole% of the whole, more preferably not less than 60 mole%, and more preferably not less than 80 mole%.

When the liquid crystal alignment film is intended to increase the pretilt angle of the liquid crystal, Y _{1 is} preferably one having a long-chain alkyl group, an aromatic ring, an aliphatic ring, a steroid skeleton, or a combination thereof in a side chain. . Such Y _{1 is} preferably Y-170 to Y-191.

In formula (5), the side chain portion is preferably a structure substituted with the following formula [III-1] or [III-2].

In the above (III-1), X ¹ represents a single bond,-(CH ₂ ) _a- (a is an integer of 1 to 15), -O-, -CH ₂ O-, -COO-, or -OCO-. X ² represents a single bond or (CH ₂ ) _b- (b is an integer from 1 to 15). X ³ represents a single bond,-(CH ₂ ) _c- (c is an integer of 1 to 15), -O-, -CH ₂ O-, -COO-, or -OCO-. X ⁴ represents a bivalent cyclic group selected from a benzene ring, a cyclohexane ring, and a heterocyclic ring, and any hydrogen atom of such a cyclic group may pass through an alkyl group having 1 to 3 carbon atoms and a carbon number of 1 Alkoxy group of 3 to 3, fluorine-containing alkyl group of 1 to 3 carbon atoms, fluorine-containing alkoxy group of 1 to 3 carbon atoms or fluorine atom substitution. In addition, X ⁴ may be selected from carbon number 17 having a steroid skeleton. Divalent organic group of ~ 51 organic group. X ⁵ represents a divalent cyclic group selected from a benzene ring, a cyclohexane ring, and a heterocyclic ring. Any hydrogen atom on the cyclic group may be an alkyl group having 1 to 3 carbon atoms and 1 carbon number. Substituted by alkoxy groups of ~ 3, fluorinated alkyl groups of 1-3 carbon atoms, fluorinated alkoxy groups of 1-3 carbon atoms or fluorine atoms. n represents an integer from 0 to 4. X ⁶ represents an alkyl group having 1 to 18 carbon atoms, a fluorine-containing alkyl group having 1 to 18 carbon atoms, an alkoxy group having 1 to 18 carbon atoms, or a fluorine-containing alkoxy group having 1 to 18 carbon atoms.

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 -COO from the viewpoint of ease of obtaining or synthesizing the raw material. -, More preferably a single bond,-(CH ₂ ) _a- (a is an integer from 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). From the viewpoint of ease of synthesis, X ^{3 is} preferably a single bond,-(CH ₂ ) _c- (c is an integer of 1 to 15), -O-, -CH ₂ O-, or -COO-, more preferably Single bond,-(CH ₂ ) _c- (c is an integer from 1 to 10), -O-, -CH ₂ O-, or -COO-.

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

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 alkoxy group having 1 to 18 carbon atoms or a fluorine-containing alkoxy group having 1 to 10 carbon atoms. More preferably, it is an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. Particularly preferred is an alkyl group having 1 to 9 carbon atoms or an alkoxy group having 1 to 9 carbon atoms.

The preferred combination of X ¹ , X ² , X ³ , X ⁴ , X ⁵ , X ⁶ and n in formula [III-1] can be exemplified by 13 with International Publication WO2011 / 132751 (published on 2011.10.27) The same combinations of (2-1) to (2-629) disclosed in Tables 6 to 47 on pages 34 to 34. In the tables of the aforementioned International Publications, X ¹ to X ⁶ in the present invention are represented by Y1 to Y6, but Y1 to Y6 can also be interpreted as X ¹ to X ⁶ .

Moreover, in (2-605) to (2-629) disclosed in the tables of the aforementioned International Publications, the organic group having a carbon number of 17 to 51 in the present invention has a carbon number of 12 having a steroid skeleton. An organic group of ~ 25 means, but an organic group having 12 to 25 carbons having a steroid skeleton can be interpreted as an organic group having 17 to 51 carbons having a steroid skeleton. Among them, (2-25) ~ (2-96), (2-145) ~ (2-168), (2-217) ~ (2- 240), (2-268) ~ (2-315), A combination of (2-364) to (2-387), (2-436) to (2-483), or (2-603) to (2-615) is preferred. The best combination is (2-49) ~ (2-96), (2-145) ~ (2-168), (2-217) ~ (2-240), (2-603) ~ (2-606) ), (2-607) to (2-609), (2-611), (2-612), or (2-624).

[化 35] ─X ⁷ ─X ⁸ [III-2]

In the above (III-2), X ⁷ represents a single bond, -O-, -CH ₂ O-, -CONH-, -NHCO-, -CON (CH ₃ )-, -N (CH ₃ ) CO-,- COO- or -OCO-. X ⁸ represents an alkyl group having 8 to 22 carbon atoms or a fluorine-containing alkyl group having 6 to 18 carbon atoms. Among them, 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 is} preferably an alkyl group having 8 to 18 carbon atoms.

It is preferable to use a structure represented by the formula [III-1] from the viewpoint of obtaining a high vertical alignment of the side chain in which the liquid crystal is vertically aligned.

In addition, the polymer having a side chain in which the liquid crystal is vertically aligned, and the ability to vertically align the liquid crystal varies depending on the structure of the side chain in which the liquid crystal is vertically aligned. In general, when the amount of the side chain in which the liquid crystal is vertically aligned is increased, , The ability to make the liquid crystal vertical alignment increases, and decreases as it decreases. In addition, when having a cyclic structure, the ability to vertically align liquid crystals tends to be higher than those having no cyclic structure.

In order to increase the proportion of the above structure when the pretilt angle is increased, it is preferably 1 to 30 mol% of Y _{1 as a} whole, and more preferably 1 to 20 mol%.

     <Photoreactive side chain>     

Further, in the formula (5), a structure in which a side chain portion is substituted by the following formula [VIII] or [IX] is also preferable.

The polymer contained in the liquid crystal alignment agent of the present invention may have a photoreactive side chain.

The photoreactive side chain may be possessed by a specific polymer, or may be possessed by a "polyimide precursor and / or a polyimide of a polyimide" of a polymer other than the specific polymer. .

     <Diamine containing a photoreactive side chain>     

When a photoreactive side chain is to be introduced into a specific polymer and / or a polymer other than the specific polymer, a diamine having a photoreactive side chain may be used as part of the diamine component. Examples of the diamine having a photoreactive side chain include a diamine having a side chain represented by the formula [VIII] or the formula [IX], but it is not limited thereto.

[化 36] ─R ⁸ ─R ⁹ ─R ¹⁰ [Ⅷ] ─Y ₁ ─Y ₂ ─Y ₃ ─Y ₄ ─Y ₅ ─Y ₆ [Ⅸ]

The definitions of R ⁸ , R ⁹ and R ¹⁰ in the formula [VIII] are as follows.

That is, R ⁸ represents a single bond, -CH _2- , -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N (CH ₃ ) -, -CON (CH ₃ )-, or -N (CH ₃ ) CO-. In particular, R ^8- based single bonds, -O-, -COO-, -NHCO-, or -CONH- are preferred.

R ⁹ represents a single bond, an alkylene group having 1 to 20 carbon atoms which may be substituted by a fluorine atom, and -CH ₂ -of the alkylene group may be arbitrarily substituted by -CF ₂ -or -CH = CH-, followed by any group When they are not adjacent to each other, they may be substituted by these groups; -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbocyclic ring or heterocyclic ring.

In addition, the above-mentioned divalent carbocyclic ring or heterocyclic ring specifically includes the following, but is not limited thereto.

It can be formed by a common organic synthesis method, but from the viewpoint of ease of synthesis, R ^{9 is} preferably a single bond or an alkylene group having 1 to 12 carbon atoms.

R ¹⁰ represents a photoreactive group selected from the following formula.

From the viewpoint of photoreactivity, R ^{10 is} preferably a methacryl group, an Acryl group, or a vinyl group.

In Formula [IX], Y ₁ , Y ₂ , Y ₃ , Y ₄ , Y ₅ , and Y _{6 are} defined as follows.

That is, 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 carbocyclic ring or a heterocyclic ring. The alkylene group, a divalent carbon ring or a heterocyclic ring having one or more hydrogen atoms may pass through a fluorine atom or an organic compound. Radical substitution. In the case where the following Y ₂ groups are not adjacent, -CH ₂ -may also be substituted by these groups; -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 cassia hydrazone. Y ₅ is a single bond, an alkylene group having 1 to 30 carbon atoms, a divalent carbocyclic ring or a heterocyclic ring. The alkylene group, a divalent carbocyclic ring, or one or more hydrogen atoms of a heterocyclic ring may also pass through A fluorine atom or an organic group is substituted.

When the groups below Y ₅ are not adjacent, -CH ₂ -may also be substituted by these groups; -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, -CO-.

Y ₆ represents a photopolymerizable group of acrylfluorenyl or methacrylfluorenyl.

The photoreactive side chain specifically includes the following, but is not limited thereto. In the following formulae, X ⁹ and X ¹⁰ each independently represent a single bond, -O-, -COO-, -NHCO-, or -NH-, and Y represents a carbon number of 1 to 20 which may be substituted by a fluorine atom. Of extension alkyl.

Examples of the photoreactive side chain include a group that generates a photodimerization reaction represented by the following formula and a group that generates a photopolymerization reaction.

In the above formula, Y ₁ to Y ₆ are the same as defined above.

The diamine having the above-mentioned photoreactive side chain can be mixed with the characteristics of liquid crystal alignment, pretilt angle, voltage holding characteristics, charge accumulation, etc. when used as a liquid crystal alignment film, and the response speed of a liquid crystal when used as a liquid crystal display element. Use 1 type or 2 or more types.

In addition, the diamine having a photoreactive side chain is preferably 10 to 70 mole%, more preferably 20 to 60 mole%, and particularly preferably 30 to 30 mole% of the diamine component used in the synthesis of polyamino acid. ~ 50 Mol%.

Examples of the diamine having a photoreactive side chain include a diamine having a site in the side chain that contains a radical generating structure that is decomposed by irradiation with ultraviolet rays and generates radicals.

In the formula (1), Ar, R ₁ , R ₂ , T ₁ , T ₂ , S, and Q have the following definitions.

That is, Ar represents an aromatic hydrocarbon group selected from the group consisting of phenylene, naphthyl, and biphenylene, which may be substituted with an organic group, and a hydrogen atom may be substituted with a halogen atom.

R ₁ and R ₂ are each independently an alkyl or alkoxy group having 1 to 10 carbon atoms.

T ₁ and T ₂ are each independently a single bond or -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N (CH ₃ )-,- Bonding group of CON (CH ₃ )-, -N (CH ₃ ) CO-.

S is a single bond or an unsubstituted or fluorine-substituted alkylene group having 1 to 20 carbon atoms. However, -CH ₂ -or -CF ₂ -of an alkylene group may be arbitrarily substituted by -CH = CH-. When any of the groups listed below are not adjacent, they may be substituted by these groups; -O -, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbocyclic ring, a divalent heterocyclic ring.

Q represents a structure selected from the following (in the structural formula, 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-) .

In the formula (I), the Ar group bonded to the carbonyl group is related to the absorption wavelength of ultraviolet rays. Therefore, in the case of a long wavelength, a structure having a longer conjugate length of a naphthyl group or a biphenylene group is preferred. Ar may be substituted with a substituent. The substituent is preferably an electron-donating organic group such as an alkyl group, a hydroxyl group, an alkoxy group, or an amine group.

In Formula (I), when Ar has a structure such as a naphthyl group or a biphenylene group, the solubility is deteriorated, and the difficulty of synthesis becomes high. When the wavelength of the ultraviolet rays is in a range of 250 nm to 380 nm, sufficient characteristics can be obtained even with a phenyl group, and therefore a phenyl group is most preferable.

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

In formula (I), Q is preferably an electron-donating organic group, and the above group is preferable.

In the case where Q is an amine derivative, during polymerization of the polyfluorene acid of the precursor of the polyfluorene imine, the generated carboxylic acid group and the amine group may cause a problem such as salt formation, so it is more preferably a hydroxyl group or Alkoxy.

The diaminobenzene in formula (1) may have any one of o-phenylenediamine, m-phenylenediamine, or p-phenylenediamine, but it is preferably from the viewpoint of reactivity with acid dianhydride. m-phenylenediamine, or p-phenylenediamine.

Specifically, the structure represented by the following formula is preferable from the viewpoints of ease of synthesis, height of general versatility, characteristics, and the like. In the formula, n is an integer of 2 to 8.

Examples of the polyimide precursor used in the present invention include polyamic acid or polyamic acid obtained by a reaction between a diamine component and a tetracarboxylic acid dihydrate component.

     <(B) component>     

The component (B) contained in the liquid crystal alignment agent of the present invention is a compound having an aliphatic skeleton and having three or more epoxy groups. As long as this compound has an aliphatic skeleton and has three or more epoxy groups, other structures are not particularly limited. From the viewpoint of availability and the like, it is preferably a compound represented by the following formula.

In the above formula, m is independently an integer of 1 to 10, n is an integer of 1 to 10, preferably an integer of 1 to 5, R is an alkyl group having 1 to 7 carbon atoms, preferably 2 to 6, and p, q And r are each independently 1 to 8, preferably an integer of 1 to 6.

Preferred specific examples include the compounds exemplified below.

     <Polyamidine precursor-manufacturing of polyamic acid>     

The polyamido acid of the polyamido precursor used in the present invention can be produced by the following method. Specifically, the diamine component and the tetracarboxylic dianhydride component can be carried out in the presence of an organic solvent at -20 ° C to 150 ° C, preferably 0 ° C to 50 ° C, for 30 minutes to 24 hours. It is preferably synthesized by a reaction of 1 to 12 hours.

The reaction of the diamine component and the tetracarboxylic dianhydride component is usually performed in an organic solvent. The organic solvent used at this time is not particularly limited as long as it is a polyimide precursor produced by dissolution. Specific examples of the organic solvent used in the reaction are listed below, but are not limited to those examples. Examples include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ-butyrolactone, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl Methyl sulfene or 1,3-dimethyl-imidazolinone.

When the polyimide precursor is highly soluble, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or the following formula can be used. [D-1] to an organic solvent represented by the formula [D-3].

In formula [D-1], D ¹ represents an alkyl group having 1 to 3 carbon atoms, in formula [D-2], D ² represents an alkyl group having 1 to 3 carbon atoms, and in formula [D-3], D ³ Represents an alkyl group having 1 to 4 carbon atoms.

These solvents can be used alone or in combination. Moreover, even if it is a solvent which does not dissolve a polyfluorene imide precursor, it can mix with the said solvent within the range which does not precipitate the produced polyfluorene imine precursor. In addition, the water in the solvent will hinder the polymerization reaction and cause hydrolysis of the produced polyimide precursor. Therefore, it is preferable to use a solvent that is dehydrated and dried.

The concentration of the polyamic acid polymer in the reaction system is preferably from 1 to 30% by mass, and more preferably from 5 to 20% by mass from the viewpoint that the polymer is less likely to precipitate and a high molecular weight body can be easily obtained.

The polyamidic acid prepared as described above is capable of precipitating and recovering the polymer by sufficiently stirring the reaction solution and pouring it into a weak solvent. Furthermore, after carrying out precipitation several times, washing with a weak solvent, and then drying at ordinary temperature or heating, a purified polyamic acid powder can be obtained. The weak solvent is not particularly limited, and examples thereof include water, methanol, ethanol, hexane, cellosolve, acetone, and toluene.

     <Production of Polyimide Precursor-Polyamidate>     

The polyamidate precursor of the polyamidate precursor used in the present invention can be produced by the production method of (1), (2) or (3) shown below.

     (1) When it is made of polyamic acid     

Polyamic acid esters can be produced by esterifying the polyamino acids produced as described above. Specifically, the polyamic acid and the esterifying agent are performed at -20 to 150 ° C, preferably 0 to 50 ° C, for 30 minutes to 24 hours, and preferably 1 to 4 hours in the presence of an organic solvent. To make.

The esterifying agent is preferably one which can be easily removed by purification, and examples thereof include N, N-dimethylformamide dimethyl acetal, N, N-dimethylformamide diethyl acetal, N, N -Dimethylformamide dipropylacetal, N, N-dimethylformamide dineopentylbutyl acetal, N, N-dimethylformamide di-t-butyl acetal , 1-methyl-3-p-tolyltriazene, 1-ethyl-3-p-tolyltriazene, 1-propyl-3-p-tolyltriazene, 4- (4 , 6-dimethoxy-1,3,5-triazin-2-yl) -4-methylmorpholinium chloride and the like. The addition amount of the esterifying agent is 1 mol, and preferably 2 to 6 mol equivalents relative to the repeating unit of the polyamic acid.

Examples of the organic solvent include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone or γ-butyrolactone, N, N-dimethylformamide, N, N-dimethylacetamide , Dimethylsulfinium or 1,3-dimethyl-imidazolinone. When the solvent solubility of the polyimide precursor is high, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or the like may be used. Solvents represented by the formulas [D-1] to [D-3].

These solvents can be used alone or in combination. Moreover, even if it is a solvent which does not melt | dissolve a polyfluorene imide precursor, as long as the produced | generated polyimide precursor does not precipitate, it can mix and use with the said organic solvent. In addition, the water in the solvent will hinder the polymerization reaction and cause hydrolysis of the produced polyimide precursor. Therefore, it is preferable to use a solvent that has been dehydrated and dried.

The solvent used in the above reaction is preferably N, N-dimethylformamide, N-methyl-2-pyrrolidone, or γ-butyrolactone from the solubility of the polymer. Use by mixing 2 or more types. The concentration at the time of production is preferably from 1 to 30% by mass, and more preferably from 5 to 20% by mass from the viewpoint that the polymer is less likely to precipitate and a high molecular weight body can be easily obtained.

     (2) Production by reaction of tetracarboxylic acid diester dichloride with diamine     

Polyamidate can be made from tetracarboxylic acid diester dichloride and diamine.

Specifically, the tetracarboxylic acid diester dichloride and diamine can be carried out in the presence of a base and an organic solvent at -20 to 150 ° C, preferably 0 to 50 ° C, for 30 minutes to 24 hours. It is preferably produced by reacting for 1 to 4 hours.

As the base, pyridine, triethylamine, 4-dimethylaminopyridine and the like can be used, but in order to ease the reaction, pyridine is preferred. The amount of the alkali added is preferably 2 to 4 times the mole of the tetracarboxylic acid diester dichloride from the viewpoint that an easily removable amount and a high molecular weight body can be obtained.

The solvent used in the above reaction is preferably N-methyl-2-pyrrolidone or γ-butyrolactone from the solubility of the monomers and polymers. These solvents can be used alone or in combination of two or more. The polymer concentration at the time of production is preferably 1 to 30% by mass, and more preferably 5 to 20% by mass, from the viewpoint that the polymer is less likely to cause precipitation and a high molecular weight body can be easily obtained. In addition, in order to prevent the hydrolysis of the tetracarboxylic acid diester dichloride, it is preferable that the solvent used for the production of the polyamic acid ester is dehydrated as much as possible, preferably in a nitrogen environment to prevent the incorporation of outside air.

     (3) Manufactured from tetracarboxylic diester and diamine     

Polyamidate can be produced by polycondensation of a tetracarboxylic acid diester and a diamine.

Specifically, by reacting a tetracarboxylic diester and a diamine in the presence of a condensing agent, a base, and an organic solvent at a temperature of 0 ° C to 150 ° C, preferably 0 ° C to 100 ° C, the reaction is performed for 30 minutes to 24 minutes. It is preferably produced in 3 to 15 hours.

As the condensing agent, triphenylphosphite, dicyclohexylcarbodiimide, 1-ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride, N, N 'can be used. -Carbonyldiimidazole, dimethoxy-1,3,5-triazinylmethylmorpholine, O- (benzotriazol-1-yl) -N, N, N ', N'-tetramethyl Urea tetrafluoroborate, O- (benzotriazol-1-yl) -N, N, N ', N'-tetramethylmethylurea hexafluorophosphate, (2,3-dihydro-2 -Thioxo-3-benzoxazolyl) diphenylphosphonate and the like. The addition amount of the condensing agent is preferably 2 to 3 times the mole of the tetracarboxylic acid diester.

As the base, tertiary amines such as pyridine and triethylamine can be used. The amount of the alkali added is an amount that can be easily removed and a high-molecular-weight body can be easily obtained. It is preferably 2 to 4 times the mole of the diamine component.

In the above reaction, the reaction is effectively performed by adding a Lewis acid as an additive. The Lewis acid is preferably a lithium halide such as lithium chloride or lithium bromide. The addition amount of the Lewis acid is preferably from 0 to 1.0 times the mole of the diamine component.

In the manufacturing method of the said 3 types of polyamic acid esters, the manufacturing method of said (1) or said (2) is especially preferable in order to be able to obtain a high molecular weight polyamic acid ester.

The polymer solution obtained as described above can be precipitated by pouring the polymer into a weak solvent while stirring it sufficiently. After carrying out precipitation several times, washing with a weak solvent, and drying at room temperature or heating, a purified polyamidate powder can be obtained. The weak solvent is not particularly limited, and examples thereof include water, methanol, ethanol, hexane, butyl cellosolve, acetone, and toluene.

     <Polyimide>     

The polyimide used in the present invention can be produced by subjecting the aforementioned polyamidate or polyamidic acid to imidization. In the case of producing polyimide from polyamic acid, an alkaline catalyst is added to the polyamic acid solution or the polyamic acid solution obtained by dissolving the polyamic acid resin powder in an organic solvent. Chemical imidization is simpler. Chemical fluorene imidization is preferably carried out at a relatively low temperature. In the process of fluorene imidization, it is not easy to cause the molecular weight of the polymer to decrease, so it is preferred.

Chemical amidines can be chemically amidated by agitating the polyamidates to be amidated in an organic solvent in the presence of a basic catalyst. As the organic solvent, a solvent used in the aforementioned polymerization reaction can be used. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. In particular, triethylamine is preferred because it has sufficient basicity required for the reaction.

The temperature at which the amidine imidization reaction is performed is -20 ° C to 140 ° C, preferably 0 ° C to 100 ° C, and the reaction time is performed from 1 to 100 hours. The amount of the alkaline catalyst is 0.5 to 30 mol times, preferably 2 to 20 mol times. The fluorene imidization rate of the obtained polymer can be controlled by adjusting the amount of catalyst, temperature, and reaction time. Since the added catalyst and the like remain in the solution after the fluorene imidization reaction, the fluorene imidized polymer obtained is recovered by the method described below, and redissolved with an organic solvent to form the liquid crystal of the present invention. An alignment agent is preferred.

In the case of producing polyimide from polyacrylic acid, it is simple to add a chemical chemical imidization of the catalyst to the solution of the polyamidic acid obtained by the reaction of a diamine component and a tetracarboxylic dianhydride. Chemical fluorene imidization is preferred because fluorene imidization is carried out at a relatively low temperature, and the molecular weight of the polymer is unlikely to decrease during the fluorene imidization.

The chemical amidine can be chemically amidated by agitating the polyamidate to be amidated in an organic solvent, in the presence of a basic catalyst and an acid anhydride. As the organic solvent, a solvent used in the aforementioned polymerization reaction can be used. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. Among them, pyridine is preferred because it has a moderate basicity required for the reaction. Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, pyromellitic anhydride, and the like. When acetic anhydride is used, purification after the reaction is facilitated, so it is preferable.

The temperature of the amidine imidization reaction is -20 ° C to 140 ° C, preferably 0 ° C to 100 ° C, and the reaction time is 1 to 100 hours. The amount of the alkaline catalyst is 0.5 to 30 mol times of the amino acid group, preferably 2 to 20 mol times, and the amount of the acid anhydride is 1 to 50 mol times of the amino acid group, preferably 3 to 30 mol times. 30 mol times. The fluorene imidization rate of the obtained polymer can be controlled by adjusting the amount of catalyst, temperature, and reaction time.

Since the added catalyst and the like remain in the solution after the polyimide or polyimide imidization reaction, the obtained imidized polymer is recovered by the method described below. The organic solvent is redissolved, and it is preferred as the liquid crystal alignment agent of the present invention.

The polyimide solution obtained as described above can be precipitated into the polymer by being poured into a weak solvent while being sufficiently stirred. In addition, after several times of precipitation, washing with a weak solvent, and drying at room temperature or heating, a purified polyurethane powder can be obtained.

The weak solvent is not particularly limited, and examples thereof include methanol, acetone, hexane, butyl cellosolve, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, and benzene.

     <Liquid crystal alignment agent>     

The liquid crystal alignment agent of the present invention has a form of a solution in which the component (A) and the component (B) are dissolved in an organic solvent. The molecular weight of the polymer of the component (A) is preferably 2,000 to 500,000, more preferably 5,000 to 300,000, and still more preferably 10,000 to 100,000. The number average molecular weight is preferably 1,000 to 250,000, more preferably 2,500 to 150,000, and still more preferably 5,000 to 50,000.

The content of the component (A) in the liquid crystal alignment agent of the present invention can be appropriately changed by setting the thickness of the coating film to be formed, but from the viewpoint of forming a uniform and defect-free coating film, it is preferably 1% by weight or more. From the viewpoint of storage stability of the solution, it is preferably 10% by weight or less. Among them, 2 to 8% by weight is preferred, and 3 to 7% by weight is particularly preferred.

In addition, the content of the component (B) in the liquid crystal alignment agent of the present invention is based on 100 parts by weight of the component (A) contained in the liquid crystal alignment agent, for reasons such as liquid crystal alignment property and storage stability ( PHR), preferably 1 to 30 parts by weight, and particularly preferably 3 to 15 parts by weight.

The organic solvent contained in the liquid crystal alignment agent of the present invention is not particularly limited as long as the components (A) and (B) are uniformly dissolved. Among them, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethylsulfenyl, γ-butyrolactone, 1,3-dimethyl-imidazolinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, and the like. Among them, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, and γ-butyrolactone are preferably used.

The content of the organic solvent contained in the liquid crystal alignment agent of the present invention is preferably from 50 to 99% by weight, and particularly preferably from 80 to 99% by weight, from the standpoint of storage stability and coatability.

As long as the liquid crystal alignment agent of the present invention does not impair the effect of the present invention, a solvent (also referred to as a weak solvent) that improves the coating property or surface smoothness of the liquid crystal alignment film when the liquid crystal alignment agent is applied can be used. Specific examples of the following weak solvents may be mentioned, but they are not limited to these examples.

Examples include ethanol, isopropanol, 1-butanol, 2-butanol, isobutyl alcohol, tert-butanol, 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1 -Butanol, isoamyl alcohol, tert-pentanol, 3-methyl-2-butanol, neopentyl alcohol, 1-hexanol, 2-methyl-1-pentanol, 2-methyl-2-pentanol Alcohol, 2-ethyl-1-butanol, 1-heptanol, 2-heptanol, 3-heptanol, 1-octanol, 2-octanol, 2-ethyl-1-hexanol, cyclohexanol , 1-methylcyclohexanol, 2-methylcyclohexanol, 3-methylcyclohexanol, 1,2-ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butane Diol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, 2-methyl-2,4-pentanediol, 2- Ethyl-1,3-hexanediol, dipropyl ether, dibutyl ether, dihexyl ether, dioxane, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,2 -Butoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ether, diethylene glycol dibutyl ether, 2-pentanone, 3-pentanone, 2- Hexone, 2-heptanone, 4-heptanone, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl ethyl Ester, Glycol Acetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate, 2- (methoxymethoxy) ethanol, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol Monohexyl ether, 2- (hexyloxy) ethanol, furfuryl alcohol, diethylene glycol, propylene glycol, propylene glycol monobutyl ether, 1- (butoxyethoxy) propanol, propylene glycol monomethyl ether acetate, dipropylene glycol , Dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether ethyl Acid ester, ethylene glycol monoacetate, ethylene glycol diacetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, 2- (2-ethoxyethoxy) (Ethyl) ethyl acetate, diethylene glycol acetate, triethylene glycol, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate Esters, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl 3-ethoxypropionate, 3-methoxy Ethyl propionate, 3-ethoxypropionic acid, 3- Methoxypropionic acid, propyl 3-methoxypropionate, butyl 3-methoxypropionate, methyl lactate, ethyl lactate, n-propyl lactate, n-butyl lactate, isoamyl lactate Or a solvent represented by the aforementioned formulas [D-1] to [D-3].

Among them, 1-hexanol, cyclohexanol, 1,2-ethylene glycol, 1,2-propylene glycol, propylene glycol monobutyl ether, ethylene glycol monobutyl ether, or dipropylene glycol dimethyl ether is preferably used.

These weak solvents are preferably 1 to 80% by mass of the entire solvent contained in the liquid crystal alignment agent. Among these, 10 to 80% by mass is preferable. More preferably, it is 20 to 70% by mass.

In the liquid crystal alignment agent of the present invention, in addition to the above, as long as the effect of the present invention is not impaired, polymers other than the aforementioned (A) component may be added, and the electrical characteristics such as the dielectric constant or conductivity of the liquid crystal alignment film may be changed A dielectric or conductive substance for the purpose, a silane coupling agent for the purpose of improving the adhesion between the liquid crystal alignment film and the substrate, a crosslinkable compound for the purpose of improving the hardness or density of the film when used as the liquid crystal alignment film, In addition, when calcining a coating film, a fluorinated imidation accelerator for the purpose of fluorinated more efficiently by heating a polyfluorinated imide precursor.

In addition, to the liquid crystal alignment agent of the present invention, in order to improve the mechanical strength of the liquid crystal alignment film, the following additives may be added.

The aforementioned additive is preferably 0.1 to 30 parts by mass based on 100 parts by mass of the polymer component contained in the liquid crystal alignment agent. If it is less than 0.1 parts by mass, the effect cannot be expected, and if it exceeds 30 parts by mass, the alignment of the liquid crystal is reduced, so it is more preferably 0.5 to 20 parts by mass.

     <Liquid crystal alignment film>     

The liquid crystal alignment film of the present invention is a film obtained by applying the liquid crystal alignment agent to a substrate, and drying and calcining the substrate. The substrate to which the liquid crystal alignment agent of the present invention is applied is not particularly limited as long as it is a substrate with high transparency. Plastic substrates such as glass substrates, silicon nitride substrates, acrylic substrates, and polycarbonate substrates can be used. From the viewpoint of simplification, it is preferable to use a substrate on which an ITO (Indium Tin Oxide) electrode for liquid crystal driving is formed. In the case of a reflective liquid crystal display device, when the substrate is only one side, an opaque material such as a silicon wafer may be used. In this case, an electrode that reflects light may be used.

Examples of the method for applying the liquid crystal alignment agent of the present invention include a spin coating method, a printing method, and an inkjet method. The steps of drying and calcining after applying the liquid crystal alignment agent of the present invention can be selected at any temperature and time. Generally, in order to sufficiently remove the organic solvent contained, drying is performed at 50 ° C to 120 ° C for 1 minute to 10 minutes, and then firing is performed at 150 ° C to 300 ° C for 5 minutes to 120 minutes. The thickness of the coating film after firing is not particularly limited, but when it is too thin, the reliability of the liquid crystal display element may be reduced, so it is 5 to 300 nm, preferably 10 to 200 nm.

Examples of a method for subjecting the obtained liquid crystal alignment film to an alignment treatment include a rubbing method and a photo-alignment treatment method.

The friction treatment can be performed using an existing friction device. Examples of the material of the friction cloth at this time include cotton, nylon, and rayon. The conditions for the rubbing treatment are generally the conditions of a rotation speed of 300 to 2000 rpm, a conveying speed of 5 to 100 mm / s, and a pushing amount of 0.1 to 1.0 mm. Then, using pure water, alcohol, or the like, the residue caused by friction is removed by ultrasonic cleaning.

Specific examples of the photo-alignment treatment method include a method in which the surface of the coating film is irradiated with radiation deviating in a certain direction, and a method of applying heat treatment at a temperature of 150 to 250 ° C. to give the liquid crystal alignment energy may be mentioned. As the radiation, ultraviolet rays and visible rays having a wavelength of 100 to 800 nm can be used. Among them, ultraviolet rays having a wavelength of 100 to 400 nm are preferred, and those having a wavelength of 200 to 400 nm are particularly preferred. In addition, in order to improve the alignment of the liquid crystal, the coating film substrate may be heated at 50 to 250 ° C. while being irradiated with radiation. The radiation dose is preferably 1 to 10,000 mJ / cm ² , and particularly preferably 100 to 5,000 mJ / cm ² . The liquid crystal alignment film produced as described above can stably align liquid crystal molecules in a specific direction.

The higher the extinction ratio of polarized ultraviolet rays, the higher anisotropy can be imparted, so it is preferred. Specifically, the extinction ratio of the linearly polarized ultraviolet rays is preferably 10: 1 or more, and more preferably 20: 1 or more.

The film irradiated with the polarized radiation may be contact-treated with a solvent containing at least one selected from water and an organic solvent.

The solvent used for the contact treatment is not particularly limited as long as it is a solvent capable of dissolving a decomposed product generated by light irradiation. Specific examples include water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, 1-methoxy-2-propanol, 1-methoxy-2-propanol acetate, and butyl cellosolve. Agents, ethyl lactate, methyl lactate, diacetone alcohol, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl acetate, butyl acetate, and cyclohexyl acetate. These solvents may be used in combination of two or more.

From the viewpoint of general versatility or safety, it is more preferably at least one selected from the group consisting of water, 2-propanol, 1-methoxy-2-propanol, and ethyl lactate. Particularly preferred are water, 2-propanol, and a mixed solvent of water and 2-propanol.

In the present invention, the contact treatment of the film irradiated with the polarized radiation and the solution containing an organic solvent is preferably performed by a treatment such as a dipping treatment, a spray treatment, or the like that sufficiently contacts the film and the liquid. Among them, the method of dipping the film in a solution containing an organic solvent is preferably 10 seconds to 1 hour, more preferably 1 to 30 minutes. The contact treatment may be performed at normal temperature or heating, preferably 10 to 80 ° C, and more preferably 20 to 50 ° C. Further, if necessary, means for improving the contact such as ultrasonic waves can be implemented.

After the contact treatment, in order to remove the organic solvent in the use solution, it may be washed (washed) or dried with a low boiling point solvent such as water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, and the like. One or both.

In addition, the above-mentioned film subjected to a contact treatment with a solvent may be heated at a temperature of 150 ° C. or higher in order to dry the solvent and reorient the molecular chains in the film.

The heating temperature is preferably 150 to 300 ° C. The higher the temperature, the more the realignment of the molecular chains can be promoted, but when the temperature is too high, there is a concern that the molecular chains are decomposed. Therefore, the heating temperature is more preferably 180 to 250 ° C, and particularly preferably 200 to 230 ° C.

When the heating time is too short, the effect of realignment of the molecular chain may not be obtained. When the heating time is too long, the molecular chain may be decomposed. The time is preferably 10 seconds to 30 minutes, and more preferably 1 minute to 10 minutes.

     <Liquid crystal display element>     

The liquid crystal display element of the present invention includes a liquid crystal alignment film obtained by the method for producing a liquid crystal alignment film. The liquid crystal display element of the present invention is obtained by using the liquid crystal alignment agent of the present invention through the aforementioned liquid crystal alignment film manufacturing method to obtain a substrate with a liquid crystal alignment film, and then manufacturing a liquid crystal cell by a conventional method, and using the liquid crystal cell to make a liquid crystal display element.

As an example of a method for manufacturing a liquid crystal cell, a liquid crystal display element having a passive matrix structure will be described as an example. Moreover, it may be a liquid crystal display element having an active matrix structure in which a switching element such as a TFT (Thin Film Transistor) is provided in each pixel portion constituting an image display.

First, a transparent glass substrate is prepared. A common electrode is provided on one of the substrates, and a segment electrode is provided on the other substrate. These electrodes can be patterned into, for example, ITO electrodes to display a desired image. Next, an insulating film is provided on each substrate to cover the common electrode and the segment electrode. The insulating film may be, for example, a film made of SiO ₂ -TiO ₂ formed by a sol-gel method.

Next, the liquid crystal alignment film of the present invention is formed on each substrate. Next, the alignment film surfaces of one of the substrates and the other of the substrates are opposed to each other, and the periphery is sealed with a sealing material. In order to control the gap of the substrate, a sealing material may be mixed with a spacer. Further, it is preferable that a spacer for controlling the substrate gap is also spread on the in-plane portion where the sealing material is not provided. A part of the sealing material is provided with an opening that can be filled with liquid crystal from the outside.

Next, a liquid crystal material is injected into a space surrounded by the two substrates and the sealing material through the opening provided in the sealing material. Then, this opening is sealed with an adhesive. For the injection, a vacuum injection method may be used, or a method using a capillary phenomenon in the atmosphere may be used. Next, a polarizing plate is provided. Specifically, a pair of polarizing plates are stuck to the surface opposite to the liquid crystal layer of two substrates. Through the above steps, the liquid crystal display element of the present invention can be obtained.

In the present invention, a resin having a reactive group such as an epoxy group, an acrylic fluorenyl group, a methacryl fluorenyl group, a hydroxyl group, an allyl group, an ethyl fluorenyl group, and the like can be used as the sealant to be cured by irradiation with ultraviolet rays or heating. In particular, a hardening resin system using reactive groups having both epoxy groups and (meth) acrylfluorenyl groups is preferred.

The sealing agent of the present invention may be blended with an inorganic filler in order to improve adhesion and moisture resistance. The inorganic filler that can be used is not particularly limited, and specific examples include spherical silica, fused silica, crystalline silica, titanium oxide, titanium black, silicon carbide, silicon nitride, boron nitride, Calcium carbonate, magnesium carbonate, barium sulfate, calcium sulfate, mica, talc, clay, alumina, magnesia, zirconia, aluminum hydroxide, calcium silicate, aluminum silicate, lithium aluminum silicate, zirconium silicate, titanic acid Barium, glass fiber, carbon fiber, molybdenum disulfide, asbestos, etc., preferably spherical silica, fused silica, crystalline silica, titanium oxide, titanium black, silicon nitride, boron nitride, calcium carbonate, Barium sulfate, calcium sulfate, mica, talc, clay, aluminum oxide, aluminum hydroxide, calcium silicate, aluminum silicate. The inorganic filler may be used in combination of two or more.

When manufacturing a liquid crystal display composition of the PSA method, a liquid crystal display element can be manufactured in the following procedure.

The liquid crystal alignment agent is coated on two substrates and calcined to form a liquid crystal alignment film. The two substrates are arranged so that the liquid crystal alignment film faces each other, and a liquid crystal layer made of liquid crystal is held between the two substrates, that is, A liquid crystal layer is provided in contact with the liquid crystal alignment film, and a voltage is applied to the liquid crystal alignment film and the liquid crystal layer while irradiating ultraviolet rays to photopolymerize a polymerizable compound in the liquid crystal layer to produce a PSA system liquid crystal exhibiting a desired tilt angle. Display element.

When manufacturing such a PSA-type liquid crystal display device, when a liquid crystal alignment agent having a photoreactive side chain structure described in this specification is used, the alignment of the liquid crystal is more efficiently fixed, and the response speed is remarkably excellent. Liquid crystal display element.

The substrate used for the liquid crystal display element of the PSA method is a single-sided substrate, for example, a line / slit electrode pattern of 1 to 10 μm is formed, and a slit pattern or a special pattern is not formed on the opposite substrate. It can also be operated. With the liquid crystal display element thus structured, the manufacturing process at the time of manufacturing can be simplified, and high transmittance can be obtained.

The liquid crystal material constituting the liquid crystal layer of the vertical alignment method is not particularly limited, and for example, MLC-6608 or MLC-6609 manufactured by Merck can be used, which is mainly a negative type liquid crystal. In the PSA method, for example, a liquid crystal containing a polymerizable compound represented by the following formula (for example, MLC-3023 manufactured by Merck) can be used.

The steps of producing a liquid crystal cell by irradiating ultraviolet rays while applying a voltage to the liquid crystal alignment film and the liquid crystal layer include, for example, applying a voltage between electrodes provided on a substrate, applying an electric field to the liquid crystal alignment film and the liquid crystal layer, and maintaining the electric field State, the method of irradiating ultraviolet rays. Here, the voltage applied between the electrodes is, for example, 5 to 30 Vp-p, and preferably 5 to 20 Vp-p. The amount of ultraviolet radiation is, for example, 1 ~ 60J, preferably less than 40J. The amount of ultraviolet radiation is small, which can suppress the decrease in reliability caused by the destruction of the components constituting the liquid crystal display element, and reduce the ultraviolet irradiation time, which can improve the manufacturing efficiency. It is better.

    [Example]    

The following examples further illustrate the present invention. However, the present invention is not limited to these examples. The abbreviations of the compounds in the following and the methods for measuring each characteristic are as follows.

NMP: N-methyl-2-pyrrolidone, BCS: butyl cellosolve

DC-1: 1,3-dimethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride

DC-2: 1,2,3,4-cyclobutane tetracarboxylic dianhydride

DC-3: Bicyclic [3,3,0] octane-2,4,6,8-tetracarboxylic dianhydride,

DC-4: pyromellitic anhydride,

DA-1: p-phenylenediamine,

DA-2: 1,2-bis (4-aminophenoxy) ethane

DA-3: 1,3-bis (4-aminophenoxy) propane

DA-4: 1-tert-butoxycarbonyl-1,3-bis (4-aminophenethyl) urea, DA-5: 4- (2-methylaminoethyl) aniline

DA-6: 1,3-bis (4-aminophenethyl) urea

DA-7: 4,4'-diaminodiphenylamine

DA-8: 3,5-diaminobenzoic acid

DA-9: 3,5-diamino-N- (pyridin-3-ylmethyl) benzidine

DA-10: Compound of the following formula DA-10

DA-11: Compound of the formula DA-11n

In the following chemical formula, Boc represents t-butoxycarbonyl.

The methods for measuring each characteristic and the methods for preparing the measurement samples used in it are described below.

    <Viscosity>    

The viscosity of the polyamic acid solution is based on an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.), with a sample volume of 1.1 mL (ml), a tapered rotor TE-1 (1 ° 34 ', R24), temperature The measurement was performed at 25 ° C.

    <Adhesiveness evaluation>         [Sample production]    

Each liquid crystal alignment agent of Examples and Comparative Examples described later was applied using a spin coater, and applied to an ITO substrate having a length of 30 mm × a width of 40 mm. Next, after drying for 2 minutes on a hot plate at 80 ° C., it was calcined in a hot air circulation oven at 230 ° C. for 30 minutes to form a coating film having a film thickness of 100 nm. After the polarizing plate was irradiated with ultraviolet light of 254 nm and 150 mJ / cm ^{2 on the} coating film surface, it was calcined in a hot air circulation oven at 230 ° C. for 30 minutes to obtain a substrate with a liquid crystal alignment film.

The prepared two substrates were prepared, and one of the substrates was coated with a 4 μm bead spacer on the liquid crystal alignment film surface, and then a sealant (XN-1500T manufactured by Kyoritsu Chemical) was dropped. Next, the liquid crystal alignment film surface of the other substrate is inside, and the overlapping width of the substrates is 1 cm. At this time, the dripping amount of the sealant was adjusted so that the diameter of the sealant after bonding was 3 mm. After the two bonded substrates were fixed with a jig, they were thermally cured at 150 ° C. for 1 hour to prepare samples of Examples and Comparative Examples for evaluation of adhesion.

    [Measurement of adhesion]    

Each of the sample substrates of the above examples and comparative examples was a desktop precision universal testing machine AGS-X 500N made by Shimadzu Corporation. After fixing the end portions of the upper and lower substrates, the upper portions of the central portions of the substrates were pressed tightly to measure the peeling time. Force (N). The results of Examples and Comparative Examples are shown in Tables 3 and 4.

    <Synthesis example 1>    

In a 100 mL four-necked flask equipped with a stirring device and a nitrogen introduction tube, weigh DA-1 (0.908 g) (8.40 mmol), DA-2 (1.37 g) (5.60 mmol), and DA-3 (2.17 g) (8.40). mmol) and DA-4 (2.23 g) (5.60 mmol), 76.8 g of NMP was added, and the solution was stirred while being fed with nitrogen. While stirring this diamine solution, DC-1 (5.99 g) (26.7 mmol) was added, and 16.1 g of NMP was further added, followed by stirring at room temperature for 24 hours to obtain a solution of polyamic acid (PAA-1, viscosity: 397 mPa.s. ).

    <Synthesis example 2>    

In a 1000 mL four-necked flask with a stirring device and a nitrogen introduction tube, weigh DA-1 (9.77 g) (90 mmol), DA-2 (21.99 g) (90 mmol), DA-3 (15.50 g) (60 mmol), And DA-4 (23.91 g) (60 mmol), 891.10 g of NMP was added, and the solution was stirred while being fed with nitrogen. DC-1 (64.56 g) (288 mmol) was added while stirring with a diamine solution, and 99.0 g of NMP was further added, followed by stirring at room temperature for 24 hours to obtain a solution of polyamic acid (PAA-2, viscosity: 435 mPa. s).

    <Synthesis example 3>    

In a 500 mL four-necked flask with a stirring device and a nitrogen introduction tube, weigh DA-5 (9.01 g) (60.0 mmol) and DA-6 (26.8 g) (89.8 mmol), add 290 g of NMP, and send nitrogen Stir to dissolve. This diamine solution was stirred under water cooling while DC-2 (27.9 g) (142 mmol) was added, and then 71.4 g of NMP was added, followed by stirring at 23 ° C for 2 hours to obtain a polyamic acid solution (PAA-3). The viscosity of this polyamic acid solution at a temperature of 25 ° C was 750 mPa. s.

    <Synthesis example 4>    

In a 15-liter four-neck flask with a stirring device and a nitrogen-containing introduction tube, weigh DA-6 (238.7 g) (800 mmol) and DA-7 (637.6 g) (3200 mmol), and add 8175.5 g of NMP. Stir to dissolve. While stirring this diamine solution under water cooling, DC-2 (176.5 g) (900 mmol) and DC-3 (750.6 g) (3000 mmol) were added, 2043.9 g of NMP was added, and the mixture was stirred at 23 ° C for 2 hours to obtain a polyfluorene. Amino acid solution (PAA-4, viscosity: 1499 mPa.s).

Table 1 shows the composition of the raw materials of the polyimide-based polymer in Synthesis Examples 1 to 4.

    [Modulation of liquid crystal alignment agent]    

Using the polyimide-based polymers obtained in the above Synthesis Examples 1 to 4, the liquid crystal alignment agents of Examples 1 to 6 and Comparative Examples 1 to 7 were prepared as follows, respectively.

The outlines of the liquid crystal alignment agents of Examples 1 to 6 and Comparative Examples 1 to 7 and the results of adhesion evaluation are shown in Tables 2, 3, and 4 described later.

    (Example 1)    

In a 20 ml sample tube with a stirrer, 3.66 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1 and 2.79 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 3 were weighed. , Adding 3.00 g of NMP, 0.85 g of NMP solution containing 3-glycidoxypropyltriethoxysilane, 0.24 g of NMP solution containing AD-1 (10 mass%), and 4.57 g of BCS, It stirred for 2 hours with the magnetic stirrer, and obtained the liquid crystal aligning agent (A-1).

    (Example 2)    

In a 20 ml sample tube with a stirrer, 3.66 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1 and the polyamino acid solution (PAA-3) obtained in Synthesis Example 3 were weighed 2.77 g, 2.83 g of NMP, 0.81 g of NMP solution containing 1% by mass of 3-glycidoxypropyltriethoxysilane, 0.42 g of NMP solution containing AD-1 (10% by mass), and 4.55 g of BCS were added And stirred with a magnetic stirrer for 2 hours to obtain a liquid crystal alignment agent (A-2).

    (Example 3)    

In a 50 ml sample tube with a stirrer, measure 4.54 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 2 and 5.40 of the polyamino acid solution (PAA-4) obtained in Synthesis Example 4. g, 5.80 g of NMP, 1.35 g of an NMP solution containing 1% by mass of 3-glycidoxypropyltriethoxysilane, 0.41 g of an NMP solution containing AD-1 (10% by mass), and 7.50 g of BCS were added. And stirred with a magnetic stirrer for 2 hours to obtain a liquid crystal alignment agent (A-3).

    (Example 4)    

In a 50 ml sample tube with a stirrer, measure 4.54 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 2 and 5.40 of the polyamino acid solution (PAA-4) obtained in Synthesis Example 4. g, 5.54 g of NMP, 1.35 g of an NMP solution containing 1% by mass of 3-glycidoxypropyltriethoxysilane, 0.68 g of an NMP solution containing AD-1 (10% by mass), and 7.50 g of BCS were added And stirred with a magnetic stirrer for 2 hours to obtain a liquid crystal alignment agent (A-4).

    (Example 5)    

In a 20 ml sample tube with a stirrer, 3.68 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1 and 2.78 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 3 were weighed. , 2.95 g of NMP, 0.87 g of a NMP solution containing 3-glycidoxypropyltriethoxysilane, 0.24 g of an NMP solution containing AD-3 (10 mass%), and 4.52 g of BCS were added, The mixture was stirred with a magnetic stirrer for 2 hours to obtain a liquid crystal alignment agent (A-5).

    (Example 6)    

In a 20 ml sample tube with a stirrer, 3.68 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1 and the polyamino acid solution (PAA-3) obtained in Synthesis Example 3 were weighed 2.80 g, 2.84 g of NMP, 0.81 g of NMP solution containing 1% by mass of 3-glycidoxypropyltriethoxysilane, 0.41 g of NMP solution containing AD-3 (10% by mass), and 4.48 g of BCS were added And stirred with a magnetic stirrer for 2 hours to obtain a liquid crystal alignment agent (A-6).

    (Comparative example 1)    

In a 20 ml sample with a stirrer, 3.69 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1 and 2.78 g of the polyamino acid solution (PAA-3) obtained in Synthesis Example 3 were weighed. , 3.22 g of NMP, 0.81 g of NMP solution containing 1% by mass of 3-glycidoxypropyltriethoxysilane, and 4.50 g of BCS were added, and stirred with a magnetic stirrer for 2 hours to obtain a liquid crystal alignment agent (B- 1).

    (Comparative example 2)    

In a 20 ml sample with a stirrer, 3.67 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1 and 2.79 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 3 were weighed. , 2.99 g of NMP, 0.83 g of NMP solution containing 1% by mass of 3-glycidoxypropyltriethoxysilane, 0.23 g of NMP solution containing AD-2 (10% by mass), and 4.49 g of BCS were added, The mixture was stirred with a magnetic stirrer for 2 hours to obtain a liquid crystal alignment agent (B-2).

    (Comparative example 3)    

In a 20 ml sample with a stirrer, 3.66 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1 and 2.79 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 3 were weighed. , 2.86 g of NMP, 0.80 g of a NMP solution containing 1% by mass of 3-glycidoxypropyltriethoxysilane, 0.40 g of a NMP solution containing AD-2 (10% by mass), and 4.53 g of BCS are added, The mixture was stirred with a magnetic stirrer for 2 hours to obtain a liquid crystal alignment agent (B-3).

    (Comparative Example 4)    

In a 20 ml sample with a stirrer, 3.68 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1 and 2.78 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 3 were weighed. , 2.98 g of NMP, 0.84 g of NMP solution containing 3-glycidoxypropyltriethoxysilane, 0.26 g of NMP solution containing AD-4 (10 mass%), and 4.49 g of BCS were added, The mixture was stirred with a magnetic stirrer for 2 hours to obtain a liquid crystal alignment agent (B-4).

    (Comparative example 5)    

In a 20 ml sample with a stirrer, 3.69 g of the polyamic acid solution (PAA-1) obtained in Synthesis Example 1 and 2.79 g of the polyamic acid solution (PAA-3) obtained in Synthesis Example 3 were weighed. , 2.82 g of NMP, 0.81 g of NMP solution containing 3-glycidoxypropyltriethoxysilane, 0.42 g of NMP solution containing AD-4 (10 mass%), and 4.48 g of BCS were added, It stirred for 2 hours with the magnetic stirrer, and obtained the liquid crystal aligning agent (B-5).

    (Comparative Example 6)    

In a 50 ml sample with a stirrer, measure 4.54 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 2 and 5.40 g of the polyamic acid solution (PAA-4) obtained in Synthesis Example 4. , 5.80 g of NMP, 1.35 g of a NMP solution containing 1% by mass of 3-glycidoxypropyltriethoxysilane, 0.405 g of an NMP solution containing AD-4 (10% by mass), and BCS (7.50 g ) And stirred with a magnetic stirrer for 2 hours to obtain a liquid crystal alignment agent (B-6).

    (Comparative Example 7)    

In a 50 ml sample with a stirrer, measure 4.54 g of the polyamic acid solution (PAA-2) obtained in Synthesis Example 2 and 5.40 g of the polyamic acid solution (PAA-4) obtained in Synthesis Example 4. , Adding 5.54 g of NMP, 1.35 g of an NMP solution containing 1% by mass of 3-glycidoxypropyltriethoxysilane, 0.675 g of an NMP solution containing AD-4 (10% by mass), and 7.50 g of BCS, It stirred for 2 hours with the magnetic stirrer, and obtained the liquid crystal aligning agent (B-7).

    <Synthesis example 5>    

DC-3 (5.00g, 20mmol), DA-8 (3.04g, 20mmol), DA-10 (6.95g, 16mmol), DA-11 (1.32g, 4mmol) were dissolved in NMP (65.3g), and After reacting at 60 ° C for 3 hours, DC-2 (3.77 g, 19.2 mmol) and NMP (15.1 g) were added, and the reaction was performed at 40 ° C for 4 hours to obtain a polyamic acid solution.

NMP was added to this polyamidic acid solution (20g), diluted to 6.5% by mass, then acetic anhydride (4.03g) and pyridine (1.25g) were added as the imidization catalyst, and the reaction was carried out at 80 ° C for 3 hours. . This reaction solution was poured into methanol (234 g), and the obtained precipitate was obtained by filtration. This precipitate was washed with methanol and dried under reduced pressure at 100 ° C to obtain polyfluorene imine powder A. The polyimide has a hydrazone imidation ratio of 74%, a number average molecular weight of 16,000, and a weight average molecular weight of 48,000.

NMP (18.0g) was added to the obtained polyfluorene imine powder A (2.0g), and it stirred at 70 degreeC for 12 hours, and was made to melt | dissolve. BCS (13.3 g) was added to this solution, and SPI-1 was obtained by stirring at room temperature for 2 hours.

    <Synthesis example 6>    

DC-3 (5.00g, 20mmol), DA-9 (7.75g, 32mmol), DA-10 (4.48g, 8mmol) were dissolved in NMP (64.9g), and after reacting at 60 ° C for 3 hours, added DC-2 (2.31g, 11.8mmol) and NMP (9.3g) were reacted at 23 ° C for 1 hour, and then DC-4 (1.74g, 8mmol) and NMP (7.0g) were added to react at 23 ° C. After 6 hours, a polyamic acid solution was obtained.

NMP was added to this polyamidic acid solution (20g), diluted to 6.5% by mass, then acetic anhydride (4.02g) and pyridine (1.25g) were added as the imidization catalyst, and reacted at 80 ° C. hour. This reaction solution was poured into methanol (234 g), and the obtained precipitate was obtained by filtration. This precipitate was washed with methanol and dried under reduced pressure at 100 ° C to obtain polyfluorene imine powder B. The polyimide has a perylene imidation ratio of 74%, a number average molecular weight of 16,000, and a weight average molecular weight of 48,000.

NMP (18.0g) was added to the obtained polyimide powder B (2.0g), and it stirred at 70 degreeC for 12 hours, and was made to melt | dissolve. BCS (13.3 g) was added to this solution, and SPI-2 was obtained by stirring at room temperature for 2 hours.

The outline of the polyfluorene-imide polymer of this invention is shown in Table 5.

    (Example 7)    

In a 20 ml sample tube with a stir bar, 5.00 g of the polyimide solution (SPI-1) obtained in Synthesis Example 5 and 5.00 g of the polyimide solution (SPI-2) obtained in Synthesis Example 6 were added. , AD-3 (0.06g), and stirred with a magnetic stirrer for 2 hours to obtain a liquid crystal alignment agent (A-7).

    (Comparative Example 8)    

In a 20 ml sample tube with a stir bar, 5.00 g of the polyimide solution (SPI-1) obtained in Synthesis Example 5 and 5.00 g of the polyimide solution (SPI-2) obtained in Synthesis Example 6 were added. And stirred with a magnetic stirrer for 2 hours to obtain a liquid crystal alignment agent (B-8).

    (Comparative Example 9)    

In a 20 ml sample tube with a stir bar, 5.00 g of the polyimide solution (SPI-1) obtained in Synthesis Example 5 and 5.00 g of the polyimide solution (SPI-2) obtained in Synthesis Example 6 were added. , AD-4 (0.06g), and stirred with a magnetic stirrer for 2 hours to obtain a liquid crystal alignment agent (B-9).

The summary of the liquid crystal alignment agent of Example 7 and Comparative Examples 8 and 9 is shown in Table 7 below, and the adhesion evaluation results of the liquid crystal alignment agents of Example 7 and Comparative Examples 8 and 9 are as follows Table 7 shows.

In addition, in the order of these adhesion evaluations, in the production of the adhesion evaluation samples, the drying on the hot plate after applying each liquid crystal alignment agent was performed, and the rest was as described above at 80 ° C instead of 70 ° C.

    [Industrial availability]    

By using the liquid crystal alignment agent of the present invention, a liquid crystal alignment film having excellent liquid crystal alignment and higher sealing and adhesion can be obtained, and therefore, it can be applied to various liquid crystal display elements requiring high display quality, especially for portable devices.

In addition, the entire contents of the specification, scope, drawings, and abstract of Japanese Patent Application No. 2016-118282 filed on June 14, 2016 are incorporated herein as a disclosure of the specification of the present invention.

Claims (13)

    A liquid crystal alignment agent, which is characterized by containing the following components (A), (B) and an organic solvent, (A) component: a polymer (B) that forms a polymer film and has the ability to align liquid crystals by alignment treatment Ingredient: A compound having an aliphatic skeleton and having three or more epoxy groups.     The liquid crystal alignment agent according to claim 1, wherein the component (A) is selected from a polyimide precursor having a structural unit represented by the following formula (1) and a polyimide of the polyimide precursor At least one polyimide, (In formula (1), X ₁ is a tetravalent organic group, Y ₁ is a divalent organic group, R ₁ is a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and A ₁ and A ₂ are each independently a hydrogen atom. Or an alkyl group having 1 to 10 carbons, an alkenyl group having 2 to 10 carbons, or an alkynyl group having 2 to 10 carbons which may have a substituent). For example, the liquid crystal alignment agent of claim 2, wherein X ₁ in the formula (1) is at least one selected from the group consisting of the structures represented by the following formulae (X-1) to (X-14), (Wherein R ₈ , R ₉ , R ₁₀ and R ₁₁ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, or an phenyl group). If the liquid crystal alignment agent of claim 2 or 3, wherein X ₁ is at least one type selected from the group consisting of the structures represented by the following formulae (X1-1) and (X1-2), The liquid crystal alignment agent according to any one of claims 2 to 4, wherein in formula (1), Y ₁ is at least one selected from the group consisting of structures represented by the following formulas (2) and (3), (In formula (2), R ₁₂ is a single bond or a bivalent organic group having 1 to 30 carbon atoms, R ₁₃ is a hydrogen atom, a halogen atom or a monovalent organic group having 1 to 30 carbon atoms, and a is 1 to 4 An integer, when a is 2 or more, R ₁₂ and R ₁₃ may be the same or different from each other, and R ₁₄ in the formula (3) is a single bond, -O-, -S-, -NR _15- , amidine A bond, an ester bond, a urea bond, or a bivalent organic group having 1 to 40 carbon atoms, and R ₁₅ is a hydrogen atom or a methyl group). The liquid crystal alignment agent according to any one of claims 1 to 5, wherein the component (B) is a compound selected from at least one of the following formulae, (In the formula, m is an integer from 1 to 10, n is an integer from 1 to 10, R is an alkyl group having 1 to 7 carbon atoms, and p, q, and r are each independently an integer from 1 to 8). The liquid crystal alignment agent according to any one of claims 1 to 5, wherein the component (B) is a compound selected from at least one of the following formulae, The liquid crystal alignment agent according to any one of claims 1 to 7, wherein the component (B) is at least one compound selected from the following structures,     The liquid crystal alignment agent according to any one of claims 1 to 8, wherein the organic solvent is selected from the group consisting of N, N-dimethylformamide, N, N-dimethylacetamide, and N-methyl-2 -Pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfene, γ-butyrolactone, 1,3-dimethyl-imidazolinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, And 4-hydroxy-4-methyl-2-pentanone in at least one species.         The liquid crystal alignment agent according to any one of claims 1 to 9, wherein the organic solvent further comprises a solvent selected from the group consisting of 1-hexanol, cyclohexanol, 1,2-ethylene glycol, 1,2-propylene glycol, and propylene glycol monobutyl ether. At least one kind of weak solvent in the group consisting of ethylene glycol monobutyl ether and dipropylene glycol dimethyl ether.         The liquid crystal alignment agent according to any one of claims 1 to 10, wherein the component (A) contains 2 to 8% by weight, and the component (B) contains 1 to 5% of the resin solid content contained in the liquid crystal alignment agent. 30% by weight, and the aforementioned organic solvent contains 50 to 99% by weight.         A liquid crystal alignment film is obtained from the liquid crystal alignment agent according to any one of claims 1 to 11.         A liquid crystal display element is provided with the liquid crystal alignment film according to claim 12.