TWI638009B - Liquid crystal alignment agent, liquid crystal alignment film and liquid crystal display element - Google Patents

Abstract

Provided is a liquid crystal alignment agent suitable for a liquid crystal display element having a fast response speed, and particularly suitable for a PSA type liquid crystal display element.

The liquid crystal alignment agent of the present invention is characterized by containing a polymer having a side chain structure represented by the following formula (I).

(Ar is shown as an aromatic hydrocarbon group; R ₁ and R _{2 are} shown as alkyl groups having 1 to 10 carbon atoms; T ₁ and T _{2 are} shown as single bonds and the like; S is shown as a single bond and the like; Q is shown as follows structure)

(R is shown as a hydrogen atom and the like; R _{3 is} shown as -CH ₂ -and the like).

Description

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

The liquid crystal alignment agent, the liquid crystal alignment film, and the liquid crystal display element related to the present invention can be used to produce a liquid crystal display element or the like in a vertical alignment method by irradiating ultraviolet rays in a state where a voltage is applied to liquid crystal molecules.

In a liquid crystal display device in which a liquid crystal molecule that is vertically aligned to a substrate is responded by an electric field (also referred to as a vertical alignment (VA) method), the manufacturing process includes applying a voltage to the liquid crystal molecules at the same time. Step of irradiating ultraviolet rays.

It is known that a liquid crystal display element of such a vertical alignment method is irradiated with ultraviolet rays while applying a voltage to a liquid crystal cell by adding a photopolymerizable compound to the liquid crystal composition in advance and using a vertical alignment film such as a polyfluorene-based system. A device that uses a technology (PSA (Polymer Sustained Alignment) method to accelerate the response speed of liquid crystals, for example, refer to Patent Document 1 and Non-Patent Document 1).

This PSA system element is generally known. Although the tilt direction of liquid crystal molecules responding to an electric field can be provided by a protrusion or a device provided on a substrate. It is controlled by being placed in a slit or the like of a display electrode, but it is a polymer that memorizes oblique directions of liquid crystal molecules by adding a photopolymerizable compound to a liquid crystal composition and applying a voltage to a liquid crystal cell while irradiating ultraviolet rays. Because the structure can be formed on the liquid crystal alignment film, the response speed of the liquid crystal display element is faster than a method in which the tilt direction of the liquid crystal molecules is controlled by only protrusions or slits.

On the other hand, the PSA-type liquid crystal display device has the following problems: the solubility of the polymerizable compound added to the liquid crystal is low, and if the amount of the polymerized compound is increased, it will precipitate at a low temperature; Amount, it is impossible to obtain a good alignment state. In addition, there is a problem that the unreacted polymerizable compound remaining in the liquid crystal becomes an impurity (contamination) in the liquid crystal, and the reliability of the liquid crystal display element is reduced. In addition, the UV irradiation treatment required in the PSA method, if the irradiation amount is large, the components in the liquid crystal will be decomposed, leading to a decrease in reliability.

Furthermore, it has been reported that, by adding a photopolymerizable compound to a liquid crystal alignment film instead of a liquid crystal composition, the response speed of a liquid crystal display element becomes faster (SC-PVA type liquid crystal display, for example, refer to non-patent literature). 2).

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2003-307720

[Non-patent literature]

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

[Non-Patent Document 2] K.HY.-J. Lee, SID 09 DIGEST, P.666-668

In recent years, as the quality of liquid crystal display elements has improved, the response speed to liquid crystals to which voltage is applied is expected to become faster. Therefore, the polymerizable compound must be able to react efficiently with irradiation of long-wavelength ultraviolet rays (which does not accompany the decomposition of the components in the liquid crystal) and exhibit the ability to align and fix. Furthermore, it is also necessary that no unreacted polymerizable compound remains after ultraviolet irradiation, so that it does not adversely affect the reliability of the liquid crystal display element.

The object of the present invention is to provide a liquid crystal alignment agent, a liquid crystal alignment film, and a liquid crystal display element which can improve the response speed of a liquid crystal display element. Or obtained by the step of reacting a polymerizable compound in a liquid crystal alignment film.

As a result of in-depth research and review conducted by the team of the present invention, it has been found that the polymer constituting the liquid crystal alignment agent is introduced with a specific structure capable of generating radicals upon irradiation of ultraviolet rays, and by using this liquid crystal alignment agent, When a liquid crystal display element obtained by a step of reacting a polymerizable compound in a liquid crystal and / or a liquid crystal alignment film is used, the above-mentioned problem can be achieved in order to improve the reactivity of the polymerizable compound, and the present invention has been completed.

That is, this invention has the following summary.

(1) a liquid crystal alignment agent comprising a polymer having a side chain structure represented by the following formula (I), (Ar is shown as an aromatic hydrocarbon group selected from the group consisting of phenylene, naphthyl, and biphenylyl, which may be substituted by organic groups, and hydrogen atoms may be substituted by halogen atoms; R ₁ and R ₂ are each independently carbon An alkyl group, alkoxy group, benzyl group, or phenethyl group having 1 to 10 atoms; if it is an alkyl group or alkoxy group, R ₁ and R _{2 may} form a ring; T ₁ and T ₂ are each independently a single bond , -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N (CH ₃ )-, -CON (CH ₃ )-, or -N (CH ₃ ) CO-; S is a single bond, or an unsubstituted or substituted carbon atom having 1 to 20 carbon atoms (however, -CH ₂ -or CF ₂ -of an alkylene group may be replaced by -CH = CH- substitution, and when any of the following groups are not adjacent to each other, they may be substituted by these groups: -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, A divalent carbocyclic ring or a divalent heterocyclic ring); Q is represented by the following structure, (R is shown as a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; R _{3 is} shown as -CH _2- , -NR-, -O-, or -S-).

(2) The liquid crystal alignment agent according to the above (1), wherein the polymer having a side chain structure represented by the aforementioned formula (I) is a polyfluorene having a side chain structure represented by the aforementioned formula (I) An amine precursor and a polymer of at least one selected from the group consisting of polyamidoimides obtained by imiminating the precursors.

(3) The liquid crystal alignment agent according to (1) or (2) above, wherein Ar in the formula (I) is a phenyl group and Q is -OR.

(4) The liquid crystal alignment agent according to any one of (1) to (3), wherein the polymer further has a side chain that vertically aligns the liquid crystal.

(5) The liquid crystal alignment agent according to the above (4), wherein the side chain for vertically aligning the liquid crystal is at least one selected from the following formulae (II-1) and (II-2),

(X ^{1 is} shown as a single bond,-(CH ₂ ) _a- (a is an integer from 1 to 15), -O-, -CH ₂ O-, -COO- or OCO-; X ^{2 is} shown as a single bond or ( CH ₂ ) _b- (b is an integer from 1 to 15); X ^{3 is} shown as a single bond,-(CH ₂ ) _c- (c is an integer from 1 to 15), -O-, -CH ₂ O-,- COO- or OCO-; X ⁴ is a divalent cyclic group selected from a benzene ring, a cyclohexane ring, and a heterocyclic ring. Any hydrogen atom on these cyclic groups may be an alkane having 1 to 3 carbon atoms. Group, alkoxy group having 1 to 3 carbon atoms, fluorinated alkyl group having 1 to 3 carbon atoms, fluorinating alkoxy group having 1 to 3 carbon atoms or fluorine atom substitution. Furthermore, X ⁴ may also be selected from steroids Divalent organic group of an organic group having 17 to 51 carbon atoms in the skeleton; X ⁵ is a divalent cyclic group selected from a benzene ring, a cyclohexane ring, and a heterocyclic ring, and any hydrogen on these cyclic groups Atoms can be substituted by alkyl groups with 1 to 3 carbon atoms, alkoxy groups with 1 to 3 carbon atoms, fluorine-containing alkyl groups with 1 to 3 carbon atoms, fluorine-containing alkoxy groups with 1 to 3 carbon atoms or fluorine atoms; n Shown as an integer from 0 to 4; X ^{6 is} shown as an alkyl group with 1 to 18 carbon atoms, a fluorine-containing alkyl group with 1 to 18 carbon atoms, an alkoxy group with 1 to 18 carbon atoms, or 1 to 18 carbon atoms (Fluoroalkoxy)

[ Chem . 4] -X ⁷ -X ⁸ [II-2] (X ^{7 is} shown as a single bond, -O-, -CH ₂ O-, -CONH-, -NHCO-, -CON (CH ₃ )-,- N (CH ₃ ) CO-, -COO- or OCO-; X ^{8 is} shown as an alkyl group having 8 to 22 carbon atoms or a fluorine-containing alkyl group having 6 to 18 carbon atoms).

(6) The liquid crystal alignment agent according to any one of (1) to (4), wherein the polymer further has a side chain including a photoreactive group in the structure.

(7) The liquid crystal alignment agent according to the above (6), wherein the structure is a side chain containing a photoreactive group and is represented by the following formula (III) or (IV), [Chem. 5] -R ⁸ -R ⁹ -R ¹⁰ [III] (R ^{8 is} shown as 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-; R ^{9 is} shown as a single bond and can be substituted by a fluorine atom of 1 to 20 carbons -CH ₂ -of an alkylene group may be arbitrarily substituted by -CF ₂ -or -CH = CH-. When any of the following groups are not adjacent to each other, they may be substituted by these groups: -O-, -COO -, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbocyclic or heterocyclic ring; R ^{10 is} shown as a photoreactive group selected from the following formula)

[化 7] -Y ₁ -Y ₂ -Y ₃ -Y ₄ -Y ₅ -Y ₆ (IV) (Y _{1 is} shown as -CH _2- , -O-, -CONH-, -NHCO-, -COO- , -OCO-, -NH-, or -CO-; Y ₂ is an alkylene group, divalent carbocyclic ring or heterocyclic ring having 1 to 30 carbon atoms, and one of the alkylene group, divalent carbocyclic ring or heterocyclic ring Or a plurality of hydrogen atoms may be substituted by fluorine atoms or organic groups; in Y ₂ , when the following groups are not adjacent to each other, -CH ₂ -may be substituted by these groups: -O-, -NHCO-, -CONH -, -COO-, -OCO-, -NH-, -NHCONH-, -CO-; Y _{3 is} shown as -CH _2- , -O-, -CONH-, -NHCO-, -COO-, -OCO- , -NH-, -CO-, or a single bond; Y _{4 is} shown as a cinnamyl group; Y ₅ is a single bond, an alkylene group having 1 to 30 carbon atoms, a divalent carbocyclic or heterocyclic ring, and this alkylene group, One or more hydrogen atoms of a divalent carbocyclic or heterocyclic ring may be substituted by a fluorine atom or an organic group; in Y ₅ , when the following groups are not adjacent to each other, -CH ₂ -may be substituted by these groups: -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, -CO-; Y _{6 is} shown as acryl group or methacryl group ( methacryl group).

(8) The liquid crystal alignment agent according to any one of (1) to (7) above, wherein the polymer contains a polyfluorene imide precursor and a polyfluorene obtained by imidizing the precursor. A polymer of at least one kind of imine, and the polyfluorene imide precursor is obtained by reacting a diamine component containing a diamine represented by the following formula (1) and a tetracarboxylic dianhydride component, (The definition of the symbol in the formula is the same as the formula (I) above).

(9) The liquid crystal alignment agent according to the above (8), wherein the polymer further contains at least one of the following polyimide precursors and polyimide obtained by imidizing the precursors. 1 type of polymer, and the polyfluorene imide precursor is obtained by reacting a diamine component containing a diamine represented by the following formula (2) with a tetracarboxylic dianhydride component, (X is the structure of the above formula [II-1] or [II-2]; n is an integer of 1 to 4).

(10) The liquid crystal alignment agent according to the above (8) or (9), wherein the polymer further contains the following polyimide precursor and polyimide obtained by imidizing the precursor A polymer of at least one kind of amine, and the polyimide precursor is a diamine component containing a diamine represented by the following formula (3) or formula (4), and a tetracarboxylic dianhydride Composition reaction, (The definitions of R ⁸ , R ⁹ and R ^{10 are} the same as those of the above formula (III))

(The definitions of Y1, Y2, Y3, Y4, Y5, and Y6 are the same as those in the above formula (IV)).

(11) The liquid crystal alignment agent according to any one of (8) to (10), wherein the diamine represented by the above (1) is 10 mol% to 80 mol% of a full diamine component.

(12) The liquid crystal alignment agent according to any one of the above (1) to (11), wherein the liquid crystal alignment agent is a liquid crystal and / or a liquid crystal alignment film contains a polymerizable compound, and a voltage is applied simultaneously A liquid crystal alignment agent for a liquid crystal display element obtained by irradiating ultraviolet rays to react the polymerizable compound.

(13) A liquid crystal alignment film obtained from the liquid crystal alignment agent according to any one of (1) to (12) above.

(14) A liquid crystal display element comprising the liquid crystal alignment film of the above (13).

(15) The liquid crystal display element according to the above (14), wherein the liquid crystal display element is polymerized by irradiating ultraviolet rays while applying a voltage. Sexual compounds are obtained.

(16) A polymer formed from a polyimide precursor having a side chain structure represented by the following formula (I) and a polyimide obtained by imidating the precursor At least one polymer selected from the group, In the formula, the definitions of R ₁ , R ₂ , T ₁ , T ₂ , S, Q, and R are the same as those in the above formula (I).

(17) a diamine represented by the following formula (I),

In the formula, the definitions of R ₁ , R ₂ , T ₁ , T ₂ , S, Q, and R are the same as those in the above formula (I).

(18) a diamine represented by the following formula,

The liquid crystal alignment agent provided by the present invention is suitable for a vertical alignment liquid crystal display element with a fast response speed, particularly a PSA type liquid crystal display element. The liquid crystal alignment agent of the present invention can produce a liquid crystal display element having a sufficiently improved response speed even in the case of irradiating ultraviolet rays having a long wavelength.

[Best Mode for Implementing Invention]

The liquid crystal alignment agent of the present invention contains at least one polymer (hereinafter also referred to as a specific polymer) having a structure represented by the formula (I) in a side chain, and a solvent. The so-called liquid crystal alignment liquid is a solution for forming a liquid crystal alignment film, and the so-called liquid crystal alignment film is a film for aligning liquid crystals in a specified direction.

As the polymer having a structure represented by the formula (I) in a side chain, at least one of a polyimide precursor and a polyimide obtained by imidating the precursor can be used. The polyfluorene imide precursor is obtained by reacting a diamine component containing a diamine represented by the above formula (IV) with a tetracarboxylic dianhydride component.

The diamine compound (hereinafter also referred to as a specific diamine) represented by the formula (IV) is a novel compound unknown in the literature.

<Side chain that generates radicals by ultraviolet irradiation>

The specific polymer contained in the liquid crystal alignment agent of the present invention has Sites that generate radicals upon irradiation with ultraviolet rays serve as side chains. The site | part which generate | occur | produces a radical by ultraviolet irradiation can be represented as following formula (I).

In the above formula (I), since the Ar system bonded by the carbonyl group is related to the absorption wavelength of ultraviolet rays, when the wavelength is increased, it is preferable that the conjugated chain length is long like a naphthyl group or a diphenyl group . 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 the formula (I), when Ar has a structure such as a naphthyl group or a diphenyl group, the solubility is deteriorated, and the difficulty of synthesis is also increased. As long as the wavelength of the ultraviolet rays is in the range of 250 nm to 380 nm, sufficient characteristics can be obtained even with a phenyl group, and therefore a phenyl group is most preferred.

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

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

(R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; R ₃ represents -CH _2- , -NR-, -O-, or -S-).

When Q is an amine derivative, when the precursor of polyimide (i.e., polyamic acid) is polymerized, the generated carboxylic acid group and the amine group may form a salt or the like, which may cause a defect. Therefore, it is preferably a hydroxyl group or an alkoxy group.

As a polymer containing a liquid crystal alignment agent, a polyfluorene imide precursor and / or a polyfluorene imine are used. When a structure of the above formula (I) is introduced into a side chain, a side chain structure of the formula (I) is used. It is better in terms of the operability of the raw materials or the ease of polymer synthesis.

In the formula (I), the site where radicals are generated by irradiation with ultraviolet rays is specifically preferred as follows. In particular, (b) or (c) is preferable from the viewpoint of reliability of the obtained liquid crystal display element.

In formula (I), -T ₁ -ST ₂ -serves as a linking group that connects a diamine benzene and a site that generates a radical by irradiation of ultraviolet rays. 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 a single bond or an alkylene group having 1 to 20 carbon atoms which may be substituted by a fluorine atom (however, -CH ₂ -or CF ₂ -of an alkylene group may be arbitrarily substituted by -CH = CH-, and now, When any of the groups are not adjacent to each other, they may be substituted by these groups: -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, divalent carbocyclic or heterocyclic) . In particular, in terms of the difficulty of synthesis, T _{2 is} most preferably -O-. In terms of the difficulty of synthesis or solubility, S is preferably an alkylene group having 2 to 10 carbon atoms, and more preferably an alkylene group having 4 to 8 carbon atoms.

<Side chain for vertical alignment of liquid crystal>

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

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

Among them, from the viewpoint of availability of raw materials or ease of synthesis, X ^{1 is} preferably a single bond,-(CH ₂ ) _a- (a is an integer of 1 to 15), -O-, -CH ₂ O -Or COO-, and 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 from 1 to 10). Among them, 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-, It is also preferably a single bond,-(CH ₂ ) _c- (c is an integer of 1 to 10), -O-, -CH ₂ O-, or COO-.

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

Among them, 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. Still more preferred 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.

As a preferable combination of X ¹ , X ² , X ³ , X ⁴ , X ⁵ , X ^6, and n in Formula [II-1], an example can be exemplified by the international publication WO2011 / 132751 (published on 2011.10.27) No. 13 (2-1) to (2-629) described in Tables 6 to 47 on pages 34 to 34 are the same combination. In the tables of the International Publication, although X ¹ to X ⁶ in the present invention are represented as Y ¹ to Y ^6, Y ¹ to Y ^{6 are} interpreted as X ¹ to X ⁶ .

In addition, (2-605) to (2-629) described in the tables of the International Publications refer to the organic group having 17 to 51 carbon atoms having a steroid skeleton in the present invention as the carbon number having a steroid skeleton. An organic group of 12 to 25 is shown, but an organic group having 12 to 25 carbons having a steroid skeleton is 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), (2-364) ~ (2-387), (2-436) ~ (2-483) or (2-603) ~ (2-615). The best combination is (2-49) ~ (2-96), (2-145) ~ (2-168), (2-217) ~ (2-240), (2-603) ~ (2-606), (2-607) ~ (2-609), (2-611), (2-612), or (2 -624).

[ Chem . 19] -X ⁷ -X ⁸ [II-2]

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

From the viewpoint of obtaining a high and stable vertical alignment of the liquid crystal, as a side chain for vertically aligning the liquid crystal, a structure represented by the formula [II-1] is preferably used.

However, polymers having side chains that orient liquid crystals vertically, the ability to orient liquid crystals vertically will vary depending on the structure of side chains that vertically align liquid crystals. Generally, when the amount of side chains that vertically align liquid crystals is large, As time goes by, the ability to align the liquid crystal vertically will increase, and when it decreases, it will decrease. In addition, when having a ring structure, the ability to align liquid crystals vertically tends to be higher than those having no ring structure.

<Photoreactive side chain>

The polymer contained in the liquid crystal alignment agent of the present invention may have a photoreactive side chain in addition to the side chain represented by the formula (I). The photoreactive side chain reacts by irradiation with light such as ultraviolet (UV) and has a functional group capable of forming a covalent bond (hereinafter also referred to as photoreactivity base).

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

[Chem. 20] -R ⁸ -R ⁹ -R ¹⁰ [III]

In 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 general organic synthesis method, but from the viewpoint of ease of synthesis, a single bond or an alkylene group having 1 to 12 carbon atoms is preferred.

Moreover, the bivalent carbocyclic ring or heterocyclic ring which substituted arbitrary -CH ₂ -in R ⁹ can be specifically exemplified as follows.

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

The photoreactive side chain is preferably present in the amount by which UV light can pass In the range where the linear irradiation reacts and forms covalent bonds to accelerate the response speed of the liquid crystal, in order to further increase the response speed of the liquid crystal, as much as possible, as long as it does not affect other characteristics.

<Polymer Forming Liquid Crystalline Alignment Agent>

The method for producing a polyfluorene imide having a specific side chain and a polyfluorene imine obtained by fluorinating the polyfluorene imide precursor are not particularly limited. Examples include: a method of polymerizing a diamine and a tetracarboxylic dianhydride having a specific side chain; a method of polymerizing a tetracarboxylic dianhydride and a diamine compound containing a specific side chain; and a tetracarboxylic dianhydride and a diamine After polymerization, a method of modifying a polymer by a certain reaction with a compound containing a specific side chain. Among them, a method of polymerizing a diamine compound containing a specific side chain and a tetracarboxylic dianhydride is preferable from the viewpoint of ease of production.

In addition to specific side chains, polyimide precursors for producing polyimide precursors having side chains and / or photoreactive side chains that vertically align liquid crystals, and polyfluorenes which are imidized with the polyimide precursors. The method of imine can also be exemplified by the same method as described above. This preferred method is also a method of polymerizing a diamine compound containing a side chain that vertically aligns liquid crystals and / or a diamine compound containing a photoreactive side chain with a tetracarboxylic dianhydride.

<Specific diamine>

The diamine (hereinafter also referred to as a specific diamine) used in the production of the above polymer (which forms the liquid crystal alignment agent of the present invention) has a borrowed A site which is decomposed by the irradiation of ultraviolet rays and generates radicals serves as a side chain.

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

The diaminobenzene in the formula (I) may have any structure of o-phenylenediamine, m-phenylenediamine, or p-phenylenediamine, and is preferred in terms of reactivity with acid dianhydride. It is m-phenylenediamine or p-phenylenediamine.

The specific amine is preferably a structure represented by the following formula from the viewpoints of ease of synthesis, high versatility, characteristics, and the like. Still, n in the formula is an integer of 2-8.

<Synthesis of Specific Diamines>

In the present invention, the specific diamine system can be synthesized by each step, or a reduction step can be used to synthesize a mononitro compound having a removable protective amine group, or a diamine can be synthesized. It can be obtained by converting a nitro group into an amine group or deprotecting a protecting group by a reduction reaction generally used.

There are various methods for the synthesis of diamine precursors, such as the following: A method of synthesizing a site that generates free radicals by external irradiation, and introducing a spacer site, and then bonding with dinitrobenzene. Still, n is an integer from 2 to 8.

In the above-mentioned reaction, although the two sites are used in the presence of a hydroxyl group, they can be selectively synthesized by optimizing the type of the base (catalyst) or the ratio of the placement.

The base used is not particularly limited, but inorganic bases such as potassium carbonate, sodium carbonate, and cesium carbonate, pyridine, dimethylaminopyridine, trimethylamine, triethylamine, and tributylamine are preferred. And other organic bases.

The method for reducing a diamine precursor (i.e., a dinitro compound) is not particularly limited. Usually, palladium-carbon, platinum oxide, Raleigh nickel, platinum carbon, rhodium-alumina, and platinum sulfide are used as catalysts. A method in which ethyl acetate, toluene, tetrahydrofuran, dioxane, alcohol-based solvents are reduced by hydrogen, hydrazine, hydrogen chloride, or the like. You can also use a pressure cooker, etc. if necessary.

On the other hand, when unsaturated bond sites are included in the structure, when palladium-carbon or platinum carbon is used, the unsaturated bond sites may be reduced and a saturated bond may be formed. Therefore, it is preferable to reduce iron or tin. Over-plated metal such as tin chloride, or poisoned palladium-carbon or platinum-carbon, iron-doped platinum-carbon, etc. are the reducing conditions for the catalyst.

In addition, the diamine derived from a diaminobenzene derivative protected with benzyl or the like can be deprotected by the reduction step described above to obtain the diamine of the present invention.

The specific diamine is preferably 10 to 80 mole% of the diamine component used in the synthesis of the polyamic acid, more preferably 20 to 60 mole%, and particularly preferably 30 to 50 mole%. Mohr%.

<Diamine having a side chain that aligns liquid crystal vertically>

As a method for introducing a side chain that vertically aligns a liquid crystal into a polyfluorene-imide-based 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 diamine compound) represented by the following formula [2].

In the formula [2], X is a structure shown in the aforementioned formula [II-1] or [II-2], n is an integer of 1 to 4, and 1 is particularly preferred.

From the viewpoint that a high and stable vertical alignment of the liquid crystal can be obtained, as the specific side chain type diamine, a diamine represented by the following formula [2-1] is preferably used.

X ¹ , X ² , X ³ , X ⁴ , X ⁵ , and n in the above formula [2-1] are the same as those respectively defined in the above formula [II-1], and, respectively, the better ones Is also the same as those defined in the above formula [II-1].

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

Specific examples of the specific side chain-type diamine include structures represented by the following formulas [2a-1] to [2a-31].

(R ^{1 is} shown as -O-, -OCH _2- , -CH ₂ O-, -COOCH ₂ -or CH ₂ OCO-, and R ² is a linear or branched alkyl group having 1 to 22 carbon atoms and carbon number. 1 to 22 linear or branched alkoxy groups, 1 to 22 carbon linear or branched fluorinated alkyl groups or fluorinated alkoxy groups).

(R ^{3 is} shown as -COO-, -OCO-, -CONH-, -NHCO-, -COOCH _2- , -CH ₂ OCO-, -CH ₂ O-, -OCH ₂ -or CH _2- , R ⁴ is Linear or branched alkyl group with 1 to 22 carbon atoms, linear or branched alkoxy group with 1 to 22 carbon atoms, linear or branched fluorine-containing alkyl group with 1 to 22 carbon atoms or Fluoroalkoxy).

(R ^{5 is} shown as -COO-, -OCO-, -CONH-, -NHCO-, -COOCH _2- , -CH ₂ OCO-, -CH ₂ O-, -OCH _2- , -CH _2- , -O -Or NH-, and R ⁶ is fluoro, cyano, trifluoromethyl, nitro, azo, formamyl, ethenyl, ethenyloxy or hydroxyl).

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

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

(A ₄ is a linear or branched alkyl group having 3 to 20 carbon atoms which may be substituted by a fluorine atom, A ₃ is 1,4-cyclohexyl or 1,4-phenylene, and A ₂ is an oxygen atom or COO- * (but the bond with "*" is bonded to A ₃ ), A ₁ is an oxygen atom or COO- * (but the bond with "*" is (CH ₂ ) a ₂ ) Bond). In addition, 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).

Among the above formulas [2a-1] to [2a-31], it is particularly preferable to use the formulas [2a-1] to [2a-6], [2a-9] to [2a-13], or [2a- 22] ~ Equations [2a-31].

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

(A ¹ is an alkyl group or a fluorine-containing alkyl group having 1 to 22 carbon atoms).

In the above formulas [2b-5] to [2b-10], A ¹ is represented as -COO-, -OCO-, -CONH-, -NHCO-, -CH _2- , -O-, -CO- or NH -, A ² is 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 above-mentioned diamines can be used singly or in combination of two or more kinds in accordance with characteristics such as liquid crystal alignment, pretilt angle, voltage holding characteristics, and stored 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 a diamine component of 5 to 50 mole% of the diamine component used in the synthesis of polyamic acid, and more preferably the diamine component. 10 ~ 40 mol%, especially preferred is 15 ~ 30 mol%.

When a diamine having a side chain that vertically aligns a liquid crystal is used, it is particularly excellent in terms of improvement in response speed and the ability to fix and align the liquid crystal.

<Diamine containing a photoreactive side chain>

Examples of the diamine having a photoreactive side chain include a diamine having a side chain represented by formula (3). Specifically, for example, a diamine represented by the following general formula (3) may be used. this.

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

The bonding position of the two amine groups (-NH ₂ ) in the formula (3) is not limited. Specifically, with respect to the bonding group of the side chain, the positions of 2,3, 2,4, 2,5, 2,6, 3,4 on the benzene ring, Position 3,5. Among them, from the viewpoint of reactivity when synthesizing polyamic acid, the positions of 2,4, 2,5, or 3,5 are preferred. If the easiness in synthesizing diamine is further added, the position of 2, 4 or 3, 5 is more preferable.

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

(X ⁹ and X ¹⁰ are each independently a single bond, -O-, -COO-, -NHCO-, or -NH-, and Y is an alkylene having 1 to 20 carbon atoms which can be substituted by a fluorine atom. base).

Moreover, as a diamine which has a photoreactive side chain, the diamine which has a photodimerization-reactive group and a photopolymerization-reactive group represented by the following formula in a side chain is mentioned.

In the above formula, Y ₁ is represented by -CH _2- , -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, or -CO-. Y ₂ is an alkylene group, divalent carbocyclic ring or heterocyclic ring having 1 to 30 carbon atoms. One or more hydrogen atoms of this alkylene group, divalent carbocyclic ring or heterocyclic ring may be substituted by fluorine atom or organic group. In Y ₂ , when the following groups are not adjacent to each other, -CH ₂ -may be substituted by these groups: -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, -CO-. Y _{3 is} shown as -CH _2- , -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH-, -CO-, or a single bond. Y _{4 is} shown as cinnamon barkyl. Y ₅ is a single bond, an alkylene group having 1 to 30 carbon atoms, a divalent carbocyclic ring or a heterocyclic ring. One or more hydrogen atoms of this alkylene group, a divalent carbocyclic ring or a heterocyclic ring may be fluorine atoms or organic Radical substitution. In Y ₅ , when the following groups are not adjacent to each other, -CH ₂ -may be substituted by these groups: -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, -CO-. Y ₆ is a photopolymerizable group of acrylfluorenyl or methacrylfluorenyl.

The above-mentioned diamine having a photoreactive side chain has characteristics such as liquid crystal alignment, pretilt angle, voltage holding characteristics, and accumulated charge when used as a liquid crystal alignment film, and response speed of liquid crystal when used as a liquid crystal display element. They can be used singly or in combination of two or more.

In addition, the diamine having a photoreactive side chain is preferably used at a content of 10 to 70 mol%, and more preferably 20 to 60 mol among the diamine components used in the synthesis of polyamic acid. %, Especially good for 30-50 mole%.

<Other diamines>

In the production of the polyfluorene imide precursor and / or the polyfluorene, without diminishing the effects of the present invention, other diamines other than the above-mentioned diamines may be used in combination as the diamine component. Specifically, for example, p-phenylenediamine, 2,3,5,6-tetramethyl-p-phenylenediamine, 2,5-dimethyl-p-phenylenediamine, and m-phenylenediamine Amine, 2,4-dimethyl-m-phenylenediamine, 2,5-diaminotoluene, 2,6-diaminotoluene, 2,5-diaminophenol, 2,4-diamine Phenol, 3,5-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 Benzene, 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, 3,3'-diaminodiphenylmethane, 3,4 '-Diaminodiphenylmethane, 2,2'-diaminodiphenylmethane, 2,3'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 3 , 3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 2,2'-diaminodiphenyl ether, 2,3'-diaminodiphenyl ether , 4,4'-sulfofluorenyl diphenylamine, 3,3'-sulfofluorenyl diphenylamine, bis (4-aminophenyl) silane, bis (3-aminophenyl) silane, dimethyl-bis (4-aminophenyl) silane, dimethyl-bis (3-aminophenyl) silane, 4,4'-thiodiphenylamine, 3,3'-thiodiphenylamine, 4,4'- Diaminodiphenylamine, 3,3'-diaminodiphenylamine, 3,4 -Diaminodiphenylamine, 2,2'-diaminodiphenylamine, 2,3'-diaminodiphenylamine, N-methyl (4,4'-diaminodiphenyl Group) amine, N-methyl (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'-diamine Benzophenone, 3,4'-diaminobenzophenone, 1,4-diaminonaphthalene, 2,2'-diaminobenzophenone, 2,3'-diaminodione Benzophenone, 1,5-Diaminonaphthalene, 1,6-Diaminonaphthalene, 1,7-Diaminonaphthalene, 1,8-Diaminonaphthalene, 2,5-Diaminonaphthalene, 2 1,6-diaminonaphthalene, 2,7-diaminonaphthalene, 2,8-diaminonaphthalene, 1,2-bis (4-aminophenyl) ethane, 1,2-bis (3-amine Phenyl) ethane, 1,3-bis (4-aminophenyl) propane, 1,3-bis (3-aminophenyl) propane, 1,4-bis (4-aminophenyl) butane, 1,4-bis (3-aminophenyl) butane, bis (3,5-diethyl-4-aminophenyl) methane , 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenyl) benzene, 1, 3-bis (4-aminophenyl) benzene, 1,4-bis (4-aminobenzyl) benzene, 1,3-bis (4-aminophenoxy) benzene, 4,4 '-[ 1,4-phenylenebis (methylene)] diphenylamine, 4,4 '-[1,3-phenylenebis (methylene)] diphenylamine, 3,4'-[1,4- Phenylene bis (methylene)] diphenylamine, 3,4 '-[1,3-phenylene bis (methylene)] diphenylamine, 3,3'-[1,4-phenylene bis (Methylene)] diphenylamine, 3,3 '-[1,3-phenylenebis (methylene)] diphenylamine, 1,4-phenylenebis [(4-aminophenyl) methyl Ketone], 1,4-phenylenebis [(3-aminophenyl) methanone], 1,3-phenylenebis [(4-aminophenyl) methanone], 1,3-phenylene Phenylbis [(3-aminophenyl) methanone], 1,4-phenylphenylbis (4-aminobenzoate), 1,4-phenylphenylbis (3-aminobenzoyl) Acid ester), 1,3-phenylene bis (4-aminobenzoate), 1,3-phenylene bis (3-aminobenzoate), bis (4-aminophenyl) ) Terephthalate, bis (3-aminophenyl) terephthalate, bis (4- Phenyl) isophthalate, bis (3-aminophenyl) isophthalate, N, N '-(1,4-phenylene) bis (4-aminobenzidine Amine), N, N '-(1,3-phenylene) bis (4-aminobenzylamine), N, N'-(1,4-phenylene) bis (3-aminophenylbenzene) (Formamidine), N, N '-(1,3-phenylene) bis (3-aminobenzamide), N, N'-bis (4-aminophenyl) p-xylylenediamine Amine, N, N'-bis (3-aminophenyl) p-xylylenediamine, N, N'-bis (4-aminophenyl) m-xylylenediamine, N, N'-bis (3-aminophenyl) m-xylylenediamine, 9,10-bis (4-aminophenyl) anthracene, 4,4'-bis (4-aminophenoxy) diphenylphosphonium, 2,2'-double [4- (4-Aminophenoxy) phenyl] propane, 2,2'-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2'-bis (4 -Aminophenyl) hexafluoropropane, 2,2'-bis (3-aminophenyl) hexafluoropropane, 2,2'-bis (3-amino-4-methylphenyl) hexafluoropropane , 2,2'-bis (4-aminophenyl) propane, 2,2'-bis (3-aminophenyl) propane, 2,2'-bis (3-amino-4-methylbenzene Propyl) propane, 3,5-diaminobenzoic acid, 2,5-diaminobenzoic acid, 1,3-bis (4-aminophenoxy) propane, 1,3-bis (3-amino (Phenoxy) propane, 1,4-bis (4-aminophenoxy) butane, 1,4-bis (3-aminophenoxy) butane, 1,5-bis (4-amino Phenoxy) pentane, 1,5-bis (3-aminophenoxy) pentane, 1,6-bis (4-aminophenoxy) hexane, 1,6-bis (3-amine Phenylphenoxy) hexane, 1,7-bis (4-aminophenoxy) heptane, 1,7- (3-aminophenoxy) heptane, 1,8-bis (4-amine Phenylphenoxy) octane, 1,8-bis (3-aminophenoxy) octane, 1,9-bis (4-aminophenoxy) nonane, 1,9-bis (3- Aminophenoxy) nonane, 1,10- (4-aminophenoxy) decane, 1,10- (3-aminophenoxy) decane, 1,11- (4-amino (Phenoxy) undecane, 1,11- (3-aminophenoxy Aromatic diamines such as undecane, 1,12- (4-aminophenoxy) dodecane, 1,12- (3-aminophenoxy) dodecane, and bis (4-amine Cyclohexyl) methane, alicyclic diamines such as bis (4-amino-3-methylcyclohexyl) methane, 1,3-diaminopropane, 1,4-diaminobutane, 1, 5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1, Aliphatic diamines such as 10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane and the like.

When other diamines are used as liquid crystal alignment films The characteristics of liquid crystal alignment, pretilt angle, voltage holding characteristics, and accumulated charge can be used singly or in combination of two or more.

<Tetracarboxylic dianhydride>

The tetracarboxylic dianhydride component which reacts with the said diamine component is not specifically limited. Specifically, for example: pyromellitic acid, 2,3,6,7-naphthalenetetracarboxylic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 1,4,5,8-naphthalenetetracarboxylic acid Acid, 2,3,6,7-anthracene tetracarboxylic acid, 1,2,5,6-anthracene tetracarboxylic acid, 3,3 ', 4,4'-biphenyltetracarboxylic acid, 2,3,3 ', 4-Biphenyltetracarboxylic acid, bis (3,4-dicarboxyphenyl) ether, 3,3', 4,4'-benzophenone tetracarboxylic acid, bis (3,4-dicarboxyl Phenyl) fluorene, bis (3,4-dicarboxyphenyl) methane, 2,2-bis (3,4-dicarboxyphenyl) propane, 1,1,1,3,3,3-hexafluoro- 2,2-bis (3,4-dicarboxyphenyl) propane, bis (3,4-dicarboxyphenyl) dimethylsilane, bis (3,4-dicarboxyphenyl) diphenylsilane, 2 , 3,4,5-pyridinetetracarboxylic acid, 2,6-bis (3,4-dicarboxyphenyl) pyridine, 3,3 ', 4,4'-diphenylphosphonium tetracarboxylic acid, 3,4 , 9,10-fluorenetetracarboxylic acid, 1,3-diphenyl-1,2,3,4-cyclobutanetetracarboxylic acid, oxodiphthalic acid, 1,2,3,4-cyclo Butanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 1,2,3,4-tetramethyl-1, 2,3,4-cyclobutanetetracarboxylic acid, 1,2-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,3-dimethyl-1,2,3, 4-cyclobutane tetracarboxylic acid, 1,2,3,4-cycloheptane tetracarboxylic acid, 2,3,4,5-tetrahydrofuran tetra Acid, 3,4-dicarboxy-1-cyclohexylsuccinic acid, 2,3,5-tricarboxycyclopentylacetic acid, 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalene Succinic acid, bicyclic [3,3,0] octane-2,4,6,8-tetracarboxylic acid, bicyclic [4,3,0] nonane-2,4,7,9-tetracarboxylic acid, bicyclic [4,4,0] decane-2,4,7,9-tetracarboxylic acid, bicyclic [4,4,0] decane- 2,4,8,10-tetracarboxylic acid, tricyclic [6.3.0.0 <2,6>] undecane-3,5,9,11-tetracarboxylic acid, 1,2,3,4-butane Tetracarboxylic acid, 4- (2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid, bicyclic [2,2,2] octyl -7-ene-2,3,5,6-tetracarboxylic acid, 5- (2,5-dioxotetrahydrofuranyl) -3-methyl-3-cyclohexane-1,2-dicarboxylic acid, Tetracyclo [6,2,1,1,0,2,7] dodecane-4,5,9,10-tetracarboxylic acid, 3,5,6-tricarboxynorbornane-2: 3,5 : 6 dicarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid and the like. Of course, depending on the characteristics of liquid crystal alignment, voltage holding characteristics, and stored charge when a liquid crystal alignment film is made, tetracarboxylic dianhydride may be used alone or in combination of two or more.

<Polymerizable compound>

The liquid crystal alignment agent of the present invention may contain "a polymerizable compound having a group for photopolymerization or photocrosslinking at two or more ends" as required; such a polymerizable compound has two or more compounds It has a terminus for photopolymerization or photocrosslinking. Here, a polymerizable compound having a group that performs photopolymerization means that the compound has a functional group that polymerizes by irradiating light. The compound having a group for photocrosslinking means that the compound has a polymer capable of reacting with a polymerizable compound by irradiating light, or a compound selected from a polyimide precursor and a polyimide precursor. A functional group that reacts with at least one type of polymer of polyfluorene imine obtained by imidization of the compound, and crosslinks the polymer with the polymer. A compound having a group for performing photocrosslinking may also react with a compound having a group for performing photocrosslinking.

By applying the liquid of the present invention containing the polymerizable compound The crystal alignment agent is used in a vertical alignment type liquid crystal display element such as a SC-PVA type liquid crystal display, as compared with a polymer having a side chain that vertically aligns a liquid crystal and a photoreactive side chain, or a polymerization thereof In the case of a sexual compound, the response speed can be significantly improved, and even a small amount of a polymerizable compound can sufficiently increase the response speed.

Examples of the group for photopolymerization or photocrosslinking include a monovalent group represented by the following formula (IV).

(R ¹² is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; Z ¹ is a divalent aromatic ring or heterocyclic group which may be substituted by an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms Ring; Z ^{2 is} shown as a monovalent aromatic ring or heterocyclic ring which may be substituted by an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms).

As specific examples of the polymerizable compound, for example, a compound represented by the following formula (V) having a group for photopolymerization at each of its two ends, and a compound represented by the following formula (VI) having: A compound having a "terminal of a polymerized group" and a "terminal having a group for photocrosslinking"; or a compound having a group for photocrosslinking at each of two terminals represented by the following formula (VII).

Yet, by the following formula (V) ~ (VII) in, R ^12, Z Z ² system ^12, Z ^1, and the same as in the formula (IV) R Z ¹ and ^2, Q ¹ is a divalent organic group. Q ^{1 is} preferably a ring having phenylene (-C ₆ H _4- ), phenylene (-C ₆ H ₄ -C ₆ H _4- ), or cyclohexyl (-C ₆ H _10- ). structure. This is because the interaction with the liquid crystal can be easily increased.

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

As a group for photopolymerization or photocrosslinking, a polymerizable compound having an acrylate group or a methacrylate group is not required even if it has an α-methylene-γ-butyrolactone group, as long as it has An acrylate group or a methacrylate group is a polymerizable compound having a structure bonded to a phenylene group through an interval such as an oxyalkylene group, and is a polymer compound having α-methylene-γ-butane at both ends as described above. The ester-based polymerizable compound is the same, which can increase the response speed particularly significantly. In addition, as long as it is a polymerizable compound having a structure in which an acrylate group or a methacrylate group is bonded to a phenylene group through an interval such as an oxyalkylene group, the thermal stability is improved, and it is sufficiently resistant to heat. A high temperature such as a firing temperature of 200 ° C or higher.

The manufacturing method of the said polymerizable compound is not specifically limited, For example, it can manufacture according to the following synthesis example. For example, the polymerizable compound represented by the above formula (4) can be represented by Taragar et al. In P. Talaga, M. Schaeffer, C. Benezra and JLStampf, Synthesis, 530 (1990 The proposed method can be synthesized by reacting 2- (bromomethyl) propenoic acid with aldehyde or ketone using SnCl ₂ . In addition, Amberlyst 15 is a strongly acidic ion exchange resin manufactured by Rohm and Haas.

(Wherein R ′ is a monovalent organic group).

In addition, 2- (bromomethyl) acrylic acid can be shown by the following reaction formulas in Ramalang et al. In K. Ramarajan, K. Kamalingam, DJO'Donnell and KDBerlin, Organic Synthesis, vol. 61, 56- 59 (1983).

As a specific synthesis example, when synthesizing a polymerizable compound represented by the above formula (1) where V is -R ¹ O- and W is -OR ^2- , and R ¹ and R ^{2 are the} same, the following reaction can be exemplified. Method 2 shown.

When synthesizing a polymerizable compound represented by the above formula (4) where R ¹ and R ² are different, a method represented by the following reaction formula can be mentioned.

In the above formula (4), when synthesizing a polymerizable compound in which V and W are single bonds, a method shown in the following reaction formula can be mentioned.

<Synthesis of Polyamic Acid>

When polyamine acid is obtained by the reaction of a diamine component and a tetracarboxylic dianhydride, a known synthetic method can be used. Generally speaking, the diamine component Method for reacting with a tetracarboxylic dianhydride component in an organic solvent. The reaction between the diamine component and the tetracarboxylic dianhydride component is advantageous because it is relatively easy to proceed in an organic solvent and does not generate by-products.

The organic solvent used for the above-mentioned reaction is not particularly limited as long as it is soluble in the generated polyamic acid. In addition, even if it is an insoluble organic solvent such as polyamic acid, it can be mixed into the above-mentioned solvent and used in a range where the generated polyamino acid and the like do not precipitate. In addition, since the water in the organic solvent hinders the polymerization reaction and further causes hydrolysis of the generated polyamic acid and the like, the organic solvent is preferably one which is dehydrated and dried.

For the organic solvent used in the above reaction, for example, N, N-dimethylformamide, N, N-dimethylacetamide, N, N-diethylformamide, N-methyl Formamidine, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 2-pyrrolidone, 1,3-dimethyl-2-imidazolinone, 3-methoxy -N, N-dimethylpropanemidamide, N-methylcaprolactam, dimethylsulfinium, tetramethylurea, pyridine, dimethylfluorene, hexamethylfluorene, γ -butane Esters, isopropanol, methoxymethylpentanol, dipentene, ethylpentyl ketone, methyl nonyl ketone, methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl ketone, Methylcelulose, ethylcelulose, methylcelulose acetate, butylcelulose acetate, ethylcelulose acetate, butylcarbitol, ethylcarbitol , 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 monoacetic acid , 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, diisobutylene, pentyl acetate, butyl butyrate, butyl ether, diisobutyl ketone, methylcyclohexyl Ene, propyl ether, dihexyl ether, dioxane, n-hexane, n-pentane, n-octane, diethyl ether, cyclohexanone, ethyl carbonate, propyl carbonate, methyl lactate Esters, ethyl lactate, methyl acetate, ethyl acetate, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, 3-ethyl Methyl ethyl propionate, ethyl 3-methoxypropionate, 3-ethoxy propionic acid, 3-methoxy propionic acid, 3-methoxy propionic acid propyl ester, 3-methoxy Butyl propionate, diethylene glycol dimethyl ether, 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 for reacting the diamine component and the tetracarboxylic dianhydride component in an organic solvent may be, for example, any of the following methods: a solution prepared by dispersing or dissolving the diamine component in an organic solvent with stirring, and then dicarboxylic acid Add the anhydride component directly, or disperse or dissolve the tetracarboxylic dianhydride component in an organic solvent and then add it; on the contrary, disperse or dissolve the tetracarboxylic dianhydride component in a solution made of an organic solvent. A method of further adding a diamine component; a method of alternately adding a tetracarboxylic dianhydride component and a diamine component, and the like. In addition, when a diamine component or a tetracarboxylic dianhydride component is formed of a plurality of compounds, they can be reacted in a mixed state in advance, or they can be individually reacted in sequence. The reaction is performed in a mixed state first, or the reactions can be sequentially performed separately. In addition, the low-molecular-weight bodies after the respective reactions can be mixed to form high-molecular-weight bodies.

The temperature at which the diamine component and the tetracarboxylic dianhydride component are reacted is, for example, -20 ° C to 150 ° C, and preferably a range of -5 ° C to 100 ° C. In addition, for the reaction system, for example, the total concentration of the diamine component and the tetracarboxylic dianhydride component in the reaction solution is preferably 1 to 50% by mass, and more preferably 5 to 30% by mass.

In the above-mentioned polymerization reaction, the ratio of the total mole number of the tetracarboxylic dianhydride component to the total mole number of the diamine component can be selected according to the molecular weight of the polyamic acid to be obtained. The same as the general polycondensation reaction, the closer this Mohr ratio is to 1.0, the larger the molecular weight of the generated polyamidic acid, if it shows a better range, it is 0.8 to 1.2.

The method for synthesizing the polyamic acid used in the present invention is not limited to the above-mentioned method, and is the same as the general method for synthesizing the polyamino acid, even if a tetracarboxylic acid or a tetracarboxylic dicarboxylic acid having a corresponding structure is used. A tetracarboxylic carboxylic acid derivative such as a halide may be used in place of the tetracarboxylic dianhydride and reacted by a known method to obtain a corresponding polyamic acid.

Examples of a method for polyimide-imidizing the above polyimide to form a polyimide include a method in which a solution of the polyacid is directly heated and then imidized, and a solution is added to the solution of the polyacid. The catalyst of the media is imidization. In addition, the rate of fluorinated imidation from polyamic acid to polyimide is not necessarily 100%.

The temperature at which the polyamidic acid is subjected to thermal hydration in a solution is 100 ° C. to 400 ° C., preferably 120 ° C. to 250 ° C., and the water generated by the fluorination reaction is excluded to the reaction system. It's better to go outside.

The catalyst of polyamic acid and imidization can be obtained by adding alkaline catalyst and acid anhydride to the solution of polyamic acid and stirring at -20 ~ 250 ℃, preferably 0 ~ 180 ℃. Implementation. The amount of the alkaline catalyst is 0.5 to 30 mol times of the amino acid group, preferably 2 to 20 mol times; 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. Examples of the basic catalyst include pyridine, triethylamine, trimethylamine, tributylamine, and trioctylamine. Among them, a pyridine system is more suitable because it has a moderate basicity when the reaction proceeds. good. Examples of the acid anhydride include acetic anhydride, trimellitic anhydride, pyromellitic dianhydride, and the like. When acetic anhydride is used, it is preferable because purification after the reaction is facilitated. The rate of ammonium imidization caused by catalyst ammonium imidization can be controlled by adjusting the amount of catalyst and adjusting the reaction temperature and reaction time.

In addition, polyamidate can be produced by reacting a tetracarboxylic acid diester dichloride with a diamine (which is the same diamine as the synthesis of the polyamidic acid described above); Alternatively, the tetracarboxylic acid diester and the diamine (which is the same diamine as the synthesis of the polyamidic acid described above) are reacted in the presence of a suitable condensing agent or base. In addition, it is also possible to synthesize a polyamidic acid in advance by the above method, and then esterify a carboxylic acid in the polyamidic acid by a polymer reaction. Specifically, for example, a tetracarboxylic acid diester dichloride and a diamine can be subjected to a temperature of -20 ° C to 150 ° C, preferably 0 ° C to 50 ° C, for 30 minutes in the presence of a base and an organic solvent. A reaction of 24 hours, preferably 1 hour to 4 hours, can synthesize polyamidate. Then, the polyamidate can be heated at a high temperature to promote dealcoholization and close the ring, thereby obtaining a polyimide.

When recovering polyimide precursors or polyimide precursors such as polyamidic acid and polyamidate generated from the reaction solution, throw the reaction solution into Put it in a weak solvent to precipitate it. Examples of the weak solvent for precipitation include methanol, acetone, hexane, butyl cyrus, heptane, methyl ethyl ketone, methyl isobutyl ketone, ethanol, toluene, benzene, and water. After being put into a weak solvent, the precipitated polymer is recovered by filtration, and can be dried under normal pressure or reduced pressure, at normal temperature or under heating. In addition, when the recovered polymer is redissolved in an organic solvent, and the operation of reprecipitation recovery is repeated 2 to 10 times, impurities in the polymer can be reduced. Examples of the weak solvent at this time include alcohols, ketones, and hydrocarbons. When three or more types of weak solvents selected from these are used, the purification efficiency can be further improved, which is preferable.

<Liquid crystal alignment agent>

The liquid crystal alignment 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 1 to 20% by mass, and more preferably It is 3 to 15% by mass, and particularly preferably 3 to 10% by mass. When the "polymerizable compound having two or more ends each having a group for photopolymerization or photocrosslinking" is contained, the content is preferably 1 to 50 parts by mass relative to 100 parts by mass of the polymer. , And preferably 5 to 30 parts by mass.

The liquid crystal alignment agent of the present invention may contain other polymers in addition to the above-mentioned polymers. At this time, the content of such other polymers in the entire polymer composition is preferably 0.5 to 80% by mass, and more preferably 20 to 50% by mass.

The molecular weight of the polymer possessed by the liquid crystal alignment agent is determined by considering the strength of the liquid crystal alignment film obtained by applying the liquid crystal alignment agent and the workability during coating film formation. When the coating film is uniform, the weight average molecular weight measured by GPC (Gel Permeation Chromatography) method is preferably 5,000-1,000,000, and more preferably 10,000-150,000.

The solvent contained in the liquid crystal alignment agent is not particularly limited, as long as it is a polymer having a structure represented by the above formula (I) in a side chain, and if necessary, "having photopolymerization at two or more ends, A polymerizable compound such as a photo-crosslinkable group or the like may be a component that can be dissolved or dispersed. For example, the organic solvent illustrated in the synthesis | combination of the said polyamic acid is mentioned. Among them, N-methyl-2-pyrrolidone, γ -butyrolactone, N-ethyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolinone, 3-methoxy- N, N-dimethylpropanemidamide is preferred from the viewpoint of solubility. Of course, you may use 2 or more types of mixed solvents.

The solvent is preferably a solvent that improves the uniformity or smoothness of the coating film, and is mixed with a solvent having a high solubility of the components contained in the liquid crystal alignment agent. Examples of such a solvent include isopropyl alcohol, methoxymethylpentanol, methyl celex, ethyl celex, butyl celex, methyl celex acetate, and butyl Kiseloth acetate, ethyl cythre acetate, butylcarbitol, ethylcarbitol, ethylcarbitol acetate, 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, diethylene glycol, diethylene glycol monoacetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dipropylene glycol monoacetate monomethyl ether, dipropylene glycol monomethyl Ether, propylene glycol monomethyl ether acetate, dipropylene glycol monoethyl ether, dipropylene Diethylene glycol 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, diisobutylene, pentyl acetate, butyl butyrate, butyl ether, diisobutyl Ketone, methylcyclohexene, propyl ether, dihexyl ether, n-hexane, n-pentane, n-octane, diethyl ether, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate Ester, n-butyl acetate, propylene glycol monoethyl ether, methyl pyruvate, ethyl pyruvate, methyl 3-methoxypropionate, methyl ethyl 3-ethoxypropionate, 3-methyl Ethoxy propionate, 3-ethoxy propionic acid, 3-methoxy propionic acid, propyl 3-methoxy propionate, butyl 3-methoxy propionate, 1-methoxy-2 -Propanol, 1-ethoxy-2-propanol, 1-butoxy-2-propanol, 1-phenoxy-2-propanol, propylene glycol monoacetate, propylene glycol diacetate, propylene glycol -1-monomethyl ether-2-acetate, propylene glycol-1-monoethyl ether-2-acetate, dipropylene glycol, 2- (2-ethoxypropoxy) propanol, lactic acid methyl Esters, ethyl lactate, n-propyl lactate, n-butyl lactate, isoamyl lactate, 2-ethyl-1-hexanol, and the like. These solvents may be mixed in plural. When these solvents are used, it is preferably 5 to 80% by mass of the entire solvent contained in the liquid crystal alignment agent, and more preferably 20 to 60% by mass.

The liquid crystal alignment agent may contain components other than the above. In this example, a compound that improves the uniformity of the film thickness or surface smoothness when the liquid crystal alignment agent is applied, a compound that improves the adhesion between the liquid crystal alignment film and the substrate, and the like can be mentioned.

Examples of compounds that improve film thickness uniformity or surface smoothness include fluorine-based surfactants, polysiloxane-based surfactants, and non-ionic boundaries. Surfactants and so on. More specifically, for example, EFTop EF301, EF303, EF352 (manufactured by TOHKEM PRODUCTS), Megafac F171, F173, R-30 (manufactured by Dainippon Ink Co., Ltd.), Florad FC430, FC431 (manufactured by Sumitomo 3M), AashiGuard AG710 , Surflon S-382, SC101, SC102, SC103, SC104, SC105, SC106 (made by Asahi Glass Co., Ltd.), etc. When using these surfactants, the use ratio is preferably 0.01 to 2 parts by mass, and more preferably 0.01 to 1 part by mass, with respect to 100 parts by mass of the total amount of polymers contained in the liquid crystal alignment agent.

Specific examples of the compound that improves the adhesion between the liquid crystal alignment film and the substrate include functional silane-containing compounds or epoxy-group-containing compounds. For example: 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-urea Propyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyl Triethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 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-aminopropyltriethoxy Silyl, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-amino Propyltriethoxysilane, N-bis (oxyethylene) -3-aminopropyltrimethoxysilane, N-bis (oxyethylene) -3-aminopropyltriethoxysilane, ethylene glycol Diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol Diglycidyl ether, glycerol diglycidyl ether, 2,2-dibromo neopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, N, N , N ', N'-Tetraglycidyl-m-xylylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N', N '-Tetraglycidyl-4, 4'-diaminodiphenylmethane, 3- (N-allyl-N-glycidyl) aminopropyltrimethoxysilane, 3- (N, N -Diglycidyl) aminopropyltrimethoxysilane and the like.

In order to increase the film strength of the liquid crystal alignment film, 2,2'-bis (4-hydroxy-3,5-dihydroxymethylphenyl) propane, tetra (methoxymethyl) bisphenol, etc. may be added. Of phenolic compounds. When these compounds are used, the total amount of the polymer contained in the liquid crystal alignment agent is preferably 0.1 to 30 parts by mass, and more preferably 1 to 20 parts by mass.

Furthermore, in addition to the above, in the liquid crystal alignment agent, as long as the effect of the present invention is not impaired, a dielectric body or a conductive material may be added for the purpose of changing the electrical properties such as the dielectric constant and conductivity of the liquid crystal alignment film. substance.

The liquid crystal alignment agent is coated on a substrate and fired, thereby forming a liquid crystal alignment film in which the liquid crystals are aligned vertically. By using the liquid crystal alignment agent of the present invention, the response speed of a liquid crystal display element using the obtained liquid crystal alignment film can be made faster. In addition, the liquid crystal alignment agent of the present invention may also contain "the light is Polymerizable compounds based on polymerization or photo-crosslinking "are not contained in the liquid crystal alignment agent or are included in the liquid crystal together with the liquid crystal alignment agent. Even in the so-called PSA mode, the photoreaction can be highly sensitive. Even with a small amount of ultraviolet radiation, a pretilt angle can be given.

For example, after the liquid crystal alignment agent of the present invention is applied to a substrate, the liquid crystal alignment agent of the present invention may be dried as necessary, and the obtained cured film may be directly used as a liquid crystal alignment film by firing. The cured film may be rubbed, irradiated with polarized light or light of a specific wavelength, or treated with an ion beam to make the PSA alignment film irradiate the liquid crystal display element after the liquid crystal is filled with a voltage. UV. Particularly suitable for use as an alignment film for PSA.

In this case, the substrate to be used is not particularly limited as long as it is a substrate having high transparency, and examples thereof include glass plates, polycarbonates, poly (meth) acrylates, polyethers, polyarylates, and polyarylates. Carbamate, polyfluorene, polyether, polyetherketone, trimethylpentene, polyolefin, polyethylene terephthalate, (meth) acrylonitrile, triethylfluorene cellulose, diethylfluorene Plastic substrates such as cellulose and cellulose acetate butyrate. In addition, the use of a substrate on which an ITO electrode or the like for driving liquid crystal is formed is preferable from the viewpoint of simplification of the manufacturing process. In addition, in a reflective liquid crystal display element, if the substrate is only one side, an opaque substrate such as a silicon wafer can also be used. In this case, an electrode that reflects light can also be used.

The application method of the liquid crystal alignment agent is not particularly limited, and examples thereof include a printing method such as screen printing, lithography, flexographic printing, an inkjet method, a spray method, a roll coating method, or a dipping, roll coating machine, Gap coating Machine, spin coater, etc. In terms of productivity, the transfer printing method is widely used in industry, and the present invention can also be suitably used.

The coating film formed by applying the liquid crystal alignment agent by the method described above can be converted into a cured film after firing. The drying step after applying the liquid crystal alignment agent on the substrate is not necessarily necessary, but it is preferably performed when the time from coating to firing is not constant for each substrate, or when firing is not directly baked after coating. Drying step. This drying may be performed so long as the solvent can be removed to such an extent that the shape of the coating film is not deformed due to the transportation of the substrate or the like, 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 to 30 minutes, and preferably 1 to 5 minutes.

The firing temperature of the coating film formed by applying the liquid crystal alignment agent is not limited, for example, 100 to 350 ° C, preferably 120 to 300 ° C, and more preferably 150 to 250 ° C. The firing time is 5 minutes to 240 minutes, preferably 10 minutes to 90 minutes, and more preferably 20 minutes to 90 minutes. Heating can be performed using a generally known method such as a hot plate, a hot air circulation furnace, an infrared furnace, or the like.

The thickness of the liquid crystal alignment film obtained after firing 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 known method can be used to fabricate a liquid crystal cell. As a specific example of the liquid crystal display element, if a liquid crystal display element having a vertical alignment method of a liquid crystal cell is provided, the liquid crystal cell has: The second substrate, the liquid crystal layer provided between the substrates, and the liquid crystal alignment film formed by the liquid crystal alignment agent of the present invention provided between the substrate and the liquid crystal layer. Specifically, it is a liquid crystal display element having a vertical alignment method of a liquid crystal cell. The liquid crystal alignment film is formed by coating the liquid crystal alignment agent of the present invention on two substrates and firing the liquid crystal alignment film. The two substrates in which the films are arranged in pairs are held between the two substrates. A liquid crystal layer made of liquid crystal is held between the two substrates, and ultraviolet rays are applied while applying a voltage to the liquid crystal alignment film and the liquid crystal layer.

The liquid crystal alignment film formed by the liquid crystal alignment agent of the present invention is used to irradiate ultraviolet rays while applying a voltage to the liquid crystal alignment film and the liquid crystal layer to polymerize a polymerizable compound and to make the polymer photoreactive side. The chains react with each other, or the photoreactive side chain of the polymer reacts with the polymerizable compound, and the alignment of the liquid crystal can be more efficiently fixed, and it becomes a liquid crystal display element having a remarkable 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 with high transparency. Usually, the substrate is a substrate on which a transparent electrode for driving liquid crystal is formed. Specific examples include the same as the substrate described in the liquid crystal alignment film. Although a substrate provided with a conventional electrode pattern or protrusion pattern can be used, the liquid crystal display element of the present invention uses the liquid crystal alignment agent of the present invention, and thus a line of, for example, 1 to 10 μm is formed on a single-sided substrate. / Slit electrode pattern, it can also operate in a structure where no slit pattern or protrusion pattern is formed on the opposite substrate, and the liquid crystal display element with this structure can simplify the manufacturing process at the time of manufacturing, and obtain High penetration.

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

In the case of a transmissive liquid crystal display element, although a substrate as described above is generally used, in a reflective liquid crystal display element, if the substrate is only one side, an opaque substrate such as a silicon wafer may be used. At this time, as the electrode formed on the substrate, a material such as aluminum that can reflect light can also be used.

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

In this invention, the method of holding this liquid crystal layer between two substrates is a well-known method. For example, a pair of substrates on which a liquid crystal alignment film is formed is prepared, and spacers such as beads are scattered on the liquid crystal alignment film of one substrate so that the side on which the liquid crystal alignment film is formed is inside to attach another A method for sealing a substrate by injecting liquid crystal under reduced pressure. In addition, one pair of substrates on which a liquid crystal alignment film is formed is prepared. The liquid crystal alignment film on one substrate is dispersed with a gap such as beads, and then the liquid crystal is dropped. Then, the surface on the side where the liquid crystal alignment film is formed is inside to attach another substrate. Liquid crystal cells can also be produced by the method of sealing. The thickness of the interval is preferably 1 to 30 μm, and more preferably 2 to 10 μm.

The step of preparing a liquid crystal cell by irradiating ultraviolet rays while applying a voltage to the liquid crystal alignment film and the liquid crystal layer may include, for example, applying a voltage between electrodes provided on a substrate to apply an electric field to the liquid crystal alignment film and the liquid crystal layer, A method of irradiating ultraviolet rays while maintaining this electric field. 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 irradiation is, for example, 1 ~ 60J, preferably 40J or less. The smaller the amount of ultraviolet irradiation, the lower the reliability caused by the destruction of the components constituting the liquid crystal display element, and the improvement of the ultraviolet irradiation time can be reduced. Manufacturing efficiency is therefore better.

As described above, when a voltage is applied to the liquid crystal alignment film and the liquid crystal layer while irradiating ultraviolet rays, the polymerizable compound reacts to form a polymer. The polymer can memorize the direction in which the liquid crystal molecules are inclined, and the response speed of the obtained liquid crystal display element can be made Get faster. In addition, when a voltage is applied to the liquid crystal alignment film and the liquid crystal layer while irradiating ultraviolet rays, a polyimide precursor having a side chain in which the liquid crystal is aligned vertically and a photoreactive side chain, and the polyimide precursor The photoreactive side chains of at least one polymer selected from the polyfluorene imine obtained by the imidization react with each other, or the photoreactive side chains of the polymer react with the polymerizable compound. The response speed of the obtained liquid crystal display element can be made faster.

[Example]

Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not limited to these examples.

<Synthesis of Diamine> (Synthesis example 1)

Step1: Synthesis of 1- (4- (2,4-dinitrophenoxy) ethoxy) phenyl) -2-hydroxy-2-methylacetone

In a 2L four-necked flask equipped with a stirrer and a nitrogen introduction tube, 100.0 g of 2,4-dinitrofluorobenzene ([Mw: 186.10 g / mol], 0.538 mol), and 2-hydroxy-4 '-(2 -Hydroxyethoxy) -2-methylpropanthene 120.6 g ([Mw: 224.25 g / mol], 0.538 mol), triethylamine 81.7 g ([Mw: 101.19 g / mol], 0.807 mol), 1000 g of THF was refluxed for 24 hours. After completion of the reaction, the mixture was concentrated on a rotary evaporator, ethyl acetate was added, and this was washed several times with pure water and physiological saline, and then dried over anhydrous magnesium sulfate.

Anhydrous magnesium sulfate was removed by filtration and concentrated on a rotary evaporator, and then recrystallized with ethyl acetate and n-hexane to obtain a milky white individual 157.0 g ([Mw: 390.34 g / mol], 0.402 mol, yield : 75%). Nuclear magnetic resonance spectrum of hydrogen atoms in the molecule ⁽¹ H-NMR spectrum) was confirmed. The measurement data are shown below.

¹ HNMR (400 MHz, CDCl ₃ ) δ: 8.75 (Ar: 1H), 8.48 to 8.45 (Ar: 1H), 8.09 to 8.05 (Ar: 2H), 7.34 to 7.31 (Ar: 1H) 7.00 to 6.96 (Ar: 2H ), 4.65 ~ 4.63 (-CH2-: 2H), 4.52 ~ 4.49 (-CH2-: 2H), 4.16 (-OH: 1H), 1.66 ~ 1.60 (-CH3 × 2, 6H) Total: 18H

Step2 Synthesis of 1- (4- (2,4-diaminophenoxy) ethoxy) phenyl) -2-hydroxy-2-methylacetone (DA-1)

In a 1 L four-necked flask, weigh 100.0 g ([Mw: 390.34 g / mol], 0.256 mol) of the dinitrobenzene derivative obtained in Step 1 and platinum-doped platinum carbon (3wt% manufactured by Evonic) 10.0. g, 500 ml of THF was added, degassing under reduced pressure and hydrogen substitution were sufficiently performed, and the reaction was allowed to proceed at room temperature for 24 hours.

After the reaction, platinum and carbon were removed by a PTFE membrane filter, and the filtrate was removed by a rotary evaporator to precipitate a solid. The obtained solid was washed with isopropyl alcohol and dried under reduced pressure to obtain 72.7 g of a pale pink solid of the target compound ([Mw: 330.38 g / mol], 0.220 mol yield: 86%) . ^{The 1} H-NMR spectrum measurement data are shown below.

¹ HNMR (400 MHz, CDCl ₃ ) δ: 8.09 to 8.05 (Ar: 2H), 7.01 to 6.97 (Ar: 2H), 6.70 to 6.68 (Ar: 1H), 6.12 (Ar: 1H), 4.36 to 4.33 (-CH2 -: 2H), 4.29 ~ 4.27 (-OH & -CH2-: 3H), 3.7 (-NH2: 2H), 3.39 (-NH2: 2H), 1.64 ~ 1.63 (-CH3 × 2: 6H) Total: 22H

(Synthesis example 2)

Step1 Synthesis of 2- (4- (2-hydroxy-2-methylpropionyl) phenoxy) ethyl 3,5-dinitrobenzoate

In a 2L four-necked flask equipped with a stirrer and a nitrogen introduction tube, 100.0 g of 2-hydroxy-4 '-(2-hydroxyethoxy) -2-methylpropanylbenzene ([Mw: 224.25g / mol] , 0.446 mol), 118.6 g of pyridine ([Mw: 79.10 g / mol], 1.50 mol), 1000 g of THF, and gradually maintaining 123.3 g of 3,5-dinitrobenzidine chloride (103.3 g) while maintaining the temperature below 10 ° C [Mw: 230.56 g / mol], 0.535 mol), and returned to room temperature after 30 minutes, and reacted for 12 hours. After confirming the completion of the reaction, it was concentrated on a rotary evaporator, ethyl acetate was added, and this was washed several times with an aqueous potassium carbonate solution (10% solution), and further washed several times with pure water and physiological saline, and then with anhydrous water. It was dried with magnesium sulfate.

Anhydrous magnesium sulfate was removed by filtration and concentrated on a rotary evaporator to obtain 162.3 g ([Mw: 418.35 g / mol], 0.388 mmol, yield: 76%) of a yellow liquid as a target substance. ^{The 1} H-NMR spectrum measurement data are shown below.

¹ HNMR (400 MHz, CDCl ₃ ) δ: 9.24 (Ar: 1H), 9.18 (Ar: 2H), 8.10 to 8.07 (Ar: 2H), 7.02 to 6.98 (Ar: 2H), 4.86 to 4.84 (-CH2-: 2H), 4.47 ~ 4.44 (-CH2-: 2H), 4.15 ~ 4.10 (-OH: 1H), 1.64 ~ 1.61 (-CH3 × 2: 6H) Total: 18H

Step2 Synthesis of 2- (4- (2-hydroxy-2-methylpropionyl) phenoxy) ethyl 3,5-diaminobenzoate (DA-2)

In a 1 L four-necked flask, weigh 150.0 g ([Mw: 390.34 g / mol], 0.384 mol) of dinitrobenzene derivative obtained in Step 1 and 10.0 g of palladium-carbon (5 wt% water), and add 500 ml of THF. Degassing and hydrogen substitution were carried out under reduced pressure, and the reaction was allowed to proceed at room temperature for 24 hours.

After the reaction was completed, palladium-carbon was removed by a PTFE membrane filter, and the filtrate was removed by a rotary evaporator to precipitate a solid. The obtained solid was recrystallized from a mixed solvent of ethyl acetate and n-hexane (weight ratio: 2: 1), and dried under reduced pressure to obtain 124.0 g ([Mw: 358.39 g / mol], 0.346 mol yield: 90%). ^{The 1} H-NMR spectrum measurement data are shown below.

¹ HNMR (400 MHz, d ₆ -DMSO) δ: 8.21 to 8.20 (Ar: 2H), 7.06 to 7.03 (Ar: 2H), 6.45 (Ar: 2H), 6.40 (Ar: 1H), 6.03 (-OH: 1H ), 5.01 (-NH2 × 2: 4H), 4.53 ~ 4.52 (-CH2-: 2H), 4.37 ~ 4.36 (-CH2-: 2H), 1.39 (-CH3 × 2: 6H) Total: 22H

<Preparation of liquid crystal alignment agent>

The abbreviations in the following are as follows.

(Acid dianhydride)

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

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

PMDA: trimellitic anhydride

TCA: 2,3,5-tricarboxycyclopentylacetic acid-1,4,2,3-acid dianhydride

(Diamine)

m-PDA: m-phenylenediamine

DBA: 3,5-diaminobenzoic acid

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

4DABP: 4,4'-diaminobenzophenone shown below

DA-1 to DA-2: Diamine generated by the following radicals obtained in Synthesis Examples 1 and 2

DA-3 ~ DA-4: The following photoreactive diamines

DA-6 ~ DA-9: The following vertical alignment diamines

<Solvent>

NMP: N-methyl-2-pyrrolidone

BCS: Butyl Cellulose

<Additives>

3AMP: 3-picolylamine

<Polymerizable compound>

Polymerizable compounds represented by the following formulas RM1 and RM2

<Liquid crystal containing polymerizable compound>

30 mg of polymerizable compound RM3 (0.3% by weight for liquid crystal) was added to negative liquid crystal MLC-6608 (10.0 g) manufactured by Merck, and dissolved at 120 ° C to prepare a liquid crystal (LC1) containing a polymerizable compound. ).

<Other>

IPDI: Isophorone diisocyanate shown below

KIP150: polymer with polystyrene radical initiation function shown below (manufactured by SYNASIA)

<Determination of molecular weight of polyimide>

Device: Room temperature gel permeation chromatography (GPC) device (SSC-7200) manufactured by Senshu Scientific, column: Shodex (KD-803, KD-805)

Column temperature: 50 ℃

Eluent: N, N'-dimethylformamide (additive is lithium bromide-hydrate (LiBr.H ₂ O) 30mmol / L (liter), phosphoric acid. Anhydrous crystal (o-phosphoric acid) is 30mmol / L, (Tetrahydrofuran (THF) is 10ml / L)

Flow rate: 1.0ml / min

Standard samples for the production of calibration lines: TSK standard polyethylene oxide (molecular weight: about 9000,000, 150,000, 100,000, and 30,000) manufactured by Tosoh Corporation, and polyethylene glycol (molecular weight: about 12,000, 4,000) manufactured by Polymer Laboratories. And 1,000).

<Determination of Polyimide Imidization Rate>

20 mg of polyfluorene imide powder was placed in an NMR sampling tube stand, 5 (Kusano Science Co., Ltd.)), was added deuterated dimethyl sulfoxide _{(DMSO-d 6, 0.05%} TMS A blend) 1.0 ml, ultrasound is applied to effect complete solution. This solution was used to measure a proton NMR at 500 MHz using an NMR measuring machine (JNW-ECA500) manufactured by JEOL. The hydrazone imidization rate is determined by using protons from which the structure does not change before and after hydrazone imidization as the reference proton. The cumulative peak value of this proton and the protons from the NH group of sulfamic acid appearing near 9.5 to 10.0 ppm The cumulative peak value is obtained using the following formula. Yet, the following formula, x is a proton from the NH group of acid amide peaks accumulation value; the cumulative value of the reference Y is a peak of a proton; [alpha] is a polyamide acid (XI imidization rate of 0%) relative XI Ratio of the number of reference protons per amino acid NH matrix proton.

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

(Example 1)

After reacting CBDA (1.86g, 10.0mmol), DA-1 (2.51g, 7.0mmol), and DA-6 (1.14g, 3.0mmol) in NMP (22.1g) for 10 hours, NMP (36.8g) was added. And BCS (27.6 g), and after stirring for 5 hours, a liquid crystal alignment agent (A) was obtained.

In addition, 0.06 g of a polymerizable compound RM1 (10% by mass in terms of solid content) was added to 10.0 g of the liquid crystal alignment agent (A), and stirred at room temperature for 3 hours to dissolve the liquid crystal alignment agent (A1). .

In addition, 0.06 g of a polymerizable compound RM2 (10% by mass in terms of solid content) was added to 10.0 g of the liquid crystal alignment agent (A), and stirred at room temperature for 3 hours to dissolve the liquid crystal alignment agent (A2). .

(Example 2)

CBDA (1.86g, 10.0mmol), DA-1 (1.08g, 3.0mmol), DA-4 (1.06g, 4.0mmol), DA-7 (1.30g, 3.0mmol) were added in NMP (21.2g) After 10 hours of reaction, NMP (35.3 g) and BCS (26.5 g) were added, and after stirring for 5 hours, a liquid crystal alignment agent (B) was obtained.

In addition, 0.06 g of a polymerizable compound RM1 (10% by mass for solid content) was added to 10.0 g of the liquid crystal alignment agent (B), and the liquid crystal alignment agent (B1) was prepared by stirring at room temperature for 3 hours to dissolve. .

(Example 3)

PMDA (0.65g, 3.0mmol), DBA (0.46g, 3.0mmol), DA-2 (0.73g, 2.0mmol), DA-3 (0.93g, 2.0mmol), DA-9 (1.20g, 3.0mmol) ) After reacting for 30 minutes in NMP (15.9 g), CBDA (1.31 g, 7.0 mmol) and NMP (5.3 g) were added and the reaction was further allowed to proceed for 10 hours. NMP (35.2g) and BCS (26.4g) were added, and after stirring for 5 hours, the liquid crystal aligning agent (C) was obtained.

In addition, 0.06 g of a polymerizable compound RM1 (10% by mass for solid content) was added to 10.0 g of the liquid crystal alignment agent (C), and the liquid crystal alignment agent (C1) was prepared by stirring at room temperature for 3 hours to dissolve. .

(Example 4)

After BODA (2.38, 10.0 mmol), DA-2 (4.39 g, 13.0 mmol), and DA-9 (2.28 g, 6.0 mmol) were dissolved in NMP (32.4 g), the reaction was carried out at 60 ° C for 5 hours, and then added CBDA (1.75 g, 9.0 mmol) and NMP (10.8 g) were reacted at 40 ° C for 10 hours to obtain a polyamic acid solution.

After adding NMP to this polyphosphonic acid solution (50 g) and diluting it to 6 mass%, acetic anhydride (5.4 g) and pyridine (2.8 g) were added as the imidization catalyst, and the reaction was carried out at 50 ° C for 3 hours. . Put this reaction solution into A The obtained precipitate was obtained by filtration in an alcohol (700 ml). This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyfluorene imide powder (D). The polyimide has an imidization ratio of 51%, a number average molecular weight of 17,000, and a weight average molecular weight of 38,000.

NMP (44.0g) was added to the obtained polyfluorene imine powder (D) (6.0g), and it stirred at 50 degreeC for 5 hours, and was made to melt | dissolve. To this solution, 6.0 g of 3AMP (1 wt% NMP solution), NMP (14.0 g), and BCS (30.0 g) were added, and the liquid crystal alignment agent (D1) was obtained by stirring at room temperature for 5 hours.

In addition, 0.06 g of polymerizable compound RM1 (10% by mass for solid content) was added to 10.0 g of the liquid crystal alignment agent (D1), and the liquid crystal alignment agent (D2) was prepared by stirring at room temperature for 3 hours to dissolve. .

(Example 5)

BODA (2.38, 10.0mmol), DBA (0.87g, 6.0mmol), DA-2 (1.26g, 4.0mmol), DA-3 (1.77g, 4.0mmol), DA-9 (2.28g, 6.0mmol) After dissolving in NMP (30.7 g) and reacting at 60 ° C. for 5 hours, CBDA (1.68 g, 9.0 mmol) and NMP (10.2 g) were added and reacting at 40 ° C. for 10 hours to obtain a polyamic acid solution.

After adding NMP to this polyphosphonic acid solution (45 g) and diluting it to 6 mass%, acetic anhydride (5.1 g) and pyridine (2.6 g) were added as the imidization catalyst, and the reaction was carried out at 50 ° C for 3 hours. . This reaction solution was poured into methanol (650 ml), and the obtained precipitate was obtained by filtration. This precipitate After washing with methanol and drying at 60 ° C under reduced pressure, a polyfluoreneimide powder (E) was obtained. The polyimide has an imidization ratio of 52%, a number average molecular weight of 13,000, and a weight average molecular weight of 27,000.

NMP (44.0 g) was added to the obtained polyfluorene imine powder (E) (6.0 g), and it was stirred at 50 ° C for 5 hours to dissolve it. To this solution, 6.0 g of 3AMP (1 wt% NMP solution), NMP (14.0 g), and BCS (30.0 g) were added, and the liquid crystal alignment agent (E1) was obtained by stirring at room temperature for 5 hours.

Furthermore, 0.06 g of polymerizable compound RM1 (10% by mass for solid content) was added to 10.0 g of the liquid crystal alignment agent (E1), and the liquid crystal alignment agent (E2) was prepared by stirring at room temperature for 3 hours to dissolve. .

In addition, 0.06 g of a polymerizable compound RM2 (10% by mass for solid content) was added to 10.0 g of the liquid crystal alignment agent (E1), and the liquid crystal alignment agent (E3) was prepared by stirring at room temperature for 3 hours to dissolve. .

(Example 6)

TCA (2.13, 10.0 mmol), 3AMPDA (1.84 g, 8.0 mmol), DA-1 (2.04 g, 6.0 mmol), DA-8 (2.98 g, 6.0 mmol) were dissolved in NMP (32.0 g), and After reacting at 80 ° C. for 5 hours, CBDA (1.68 g, 9.0 mmol) and NMP (10.7 g) were added, and the reaction was performed at 40 ° C. for 10 hours to obtain a polyamic acid solution.

After adding NMP to this polyphosphonic acid solution (45 g) to dilute to 6 mass%, acetic anhydride (4.9 g) and pyridine (2.5 g) were added as the phosphonium imidization catalyst, and the reaction was carried out at 50 ° C. for 3 hours. . Put this reaction solution into A The obtained precipitate was obtained by filtration in an alcohol (650 ml). This precipitate was washed with methanol, and dried under reduced pressure at 60 ° C to obtain a polyfluoreneimide powder (F). The polyimide has an imidization ratio of 50%, a number average molecular weight of 16,000, and a weight average molecular weight of 33,000.

NMP (44.0g) was added to the obtained polyimide powder (F) (6.0g), and it stirred at 50 degreeC for 5 hours, and was made to melt | dissolve. To this solution, 6.0 g of 3AMP (1 wt% NMP solution), NMP (14.0 g), and BCS (30.0 g) were added, and the liquid crystal alignment agent (F1) was obtained by stirring at room temperature for 5 hours.

In addition, 0.06 g of a polymerizable compound RM1 (10% by mass for solid content) was added to 10.0 g of the liquid crystal alignment agent (F1), and the liquid crystal alignment agent (F2) was prepared by stirring at room temperature for 3 hours to dissolve. .

(Comparative example 1)

After reacting CBDA (1.86g, 10.0mmol), m-PDA (0.76g, 7.0mmol), and DA-9 (1.14g, 3.0mmol) in NMP (15.1g) for 10 hours, NMP (25.1g) and BCS (18.8 g). After stirring for 5 hours, a polyamic acid solution (G) was obtained.

In addition, 0.06 g of a polymerizable compound RM1 (10% by mass in terms of solid content) was added to 10.0 g of the liquid crystal alignment agent (G), and stirred at room temperature for 3 hours to dissolve the liquid crystal alignment agent (G1). .

(Comparative example 2)

BODA (2.38, 10.0mmol), DBA (2.02g, 13.0 mmol), DA-9 (2.28g, 6.0mmol) were dissolved in NMP (25.3g), and after reacting at 80 ° C for 5 hours, CBDA (1.75g, 9.0mmol) and NMP (8.4g) were added at 40 ° C. The reaction was carried out at a temperature of 10 ° C for 10 hours to obtain a polyamic acid solution.

After adding NMP to this polyphosphonic acid solution (35 g) and diluting it to 6 mass%, acetic anhydride (4.8 g) and pyridine (2.5 g) were added as the imidization catalyst, and the reaction was allowed to proceed at 50 ° C for 3 hours. . This reaction solution was poured into methanol (500 ml), and the obtained precipitate was obtained by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyfluorene imide powder (H). The polyimide has an imidization ratio of 50%, a number average molecular weight of 18,000, and a weight average molecular weight of 37,000.

NMP (44.0g) was added to the obtained polyimide powder (H) (6.0g), and it stirred at 50 degreeC for 5 hours and was made to melt | dissolve. To this solution, 6.0 g of 3AMP (1 wt% NMP solution), NMP (14.0 g), and BCS (30.0 g) were added, and the liquid crystal alignment agent (H1) was obtained by stirring at room temperature for 5 hours.

In addition, 0.06 g of a polymerizable compound RM1 (10% by mass for solid content) was added to 10.0 g of the liquid crystal alignment agent (H1), and the liquid crystal alignment agent (H2) was prepared by stirring at room temperature for 3 hours to dissolve. .

<Making a Liquid Crystal Cell> (Example 7)

Using the liquid crystal alignment agent (A1) obtained in Example 1, a liquid crystal cell was produced in the order shown below. The liquid obtained in Example 1 Crystal alignment agent (A1), spin-coated on the ITO surface of the ITO electrode substrate with a pixel size of 100 μm × 300 μm and an ITO electrode pattern with a line / space of 5 μm each, and dried on a heating plate at 80 ° C. for 90 seconds After being fired in a hot air circulation type oven at 200 ° C for 30 minutes, a liquid crystal alignment film with a film thickness of 100 nm was formed.

In addition, the liquid crystal alignment agent (A1) was spin-coated on the ITO surface on which the electrode pattern was not formed, dried on a heating plate at 80 ° C for 90 seconds, and then fired in a hot air circulation oven at 200 ° C for 30 minutes to form a film. Liquid crystal alignment film with a thickness of 100 nm.

The two substrates mentioned above were printed with a 4 μm bead interval on the liquid crystal alignment film of one substrate, and then a sealant (solvent type thermosetting epoxy resin, Struct BondX N-1500T manufactured by Mitsui Chemicals Corporation) was printed thereon. ). Next, the side of the other substrate on which the liquid crystal alignment film is formed is set to the inside, and after bonding to the substrate just before, the sealant is hardened to produce an empty cell. Liquid crystal MLC-6608 (trade name, manufactured by Merck) was injected into this empty cell by a reduced pressure injection method to produce a liquid crystal cell.

The response speed of the obtained liquid crystal cell was measured by the following method. After that, in a state where a DC voltage of 20 V was applied to the liquid crystal cell, 10 J of UV passing through a band-pass filter of 365 nm was irradiated from the outside of the liquid crystal cell. Then, the response speed was measured, and the response speed before and after UV irradiation was compared. The pretilt angle of the pixel portion was measured for the unit cell after UV irradiation. The results are shown in Table 1.

<Measurement method of response speed>

First, a liquid crystal cell is arranged between a set of polarizing plates in a measuring device composed of a set of polarizing plates and light quantity detectors in a state of backlight and crossed Nico prisms in order. At this time, the pattern of the wired / spaced ITO electrode is at an angle of 45 ° to the orthogonal Nico prism. Furthermore, a rectangular wave having a voltage of ± 6 V and a frequency of 1 kHz was applied to the above-mentioned liquid crystal cell, and the change until the brightness observed by the light amount detector became saturated was presented to an oscilloscope, so that the brightness when no voltage was applied was 0%. , Applying a voltage of ± 4V, making the value of saturated brightness 100%, and the time required to change the brightness from 10% to 90% is the response speed.

<Measurement of pretilt angle>

LCD Analyzer LCA-LUV42A manufactured by Meiryo Technica was used.

(Examples 8 to 14, Comparative Examples 3 and 4)

Except that the liquid crystal alignment agent (A1) shown in Table 1 was used instead of the liquid crystal alignment agent (A1), the same operation was performed as in Example 7, and the response speed and the pretilt angle were measured before and after UV irradiation. These results are summarized and shown in Table 1.

As shown in Table 1, in the examples, it was confirmed that a pre-tilt angle was exhibited even by irradiation of ultraviolet rays having a wavelength of 365 nm. On the other hand, in the comparative example, even when the liquid crystal alignment film contains a polymerizable compound, a sufficient pretilt angle cannot be exhibited.

In the case of the liquid crystal alignment agent of the comparative example, it is considered that the polymerizable compound itself hardly absorbs ultraviolet rays of 365 nm, and therefore does not have a liquid crystal alignment film having a radical generating site, and does not generate radicals sufficient for the start of the polymerization reaction. The reason. On the other hand, it is considered that the liquid crystal alignment agent of the example can generate sufficient free radicals even if it is irradiated with ultraviolet rays on a long wavelength side, so that the polymerizable compound is polymerized at the liquid crystal alignment film interface to form a pretilt angle.

(Example 15)

A liquid crystal cell was produced in the same manner as in Example 7 except that the liquid crystal alignment agent (D1) was used instead of the liquid crystal alignment agent (A1), and a liquid crystal containing a polymerizable compound was used. In a state where a DC voltage of 20 V is applied to the liquid crystal cell, UV from 7J and 15J passing through a band-pass filter of 365 nm is irradiated from the outside of the liquid crystal cell, and the respective liquid crystals are compared. The response speed of the unit cell. The measurement of the pretilt angle was performed. The results are shown in Table 2.

(Comparative example 5)

A liquid crystal cell was produced in the same manner as in Example 7 except that a liquid crystal alignment agent (H1) was used in place of the liquid crystal alignment agent (A1) and a liquid crystal containing a polymerizable compound was used. In a state where a DC voltage of 20 V was applied to the liquid crystal cell, UV from 7J and 15J passing through a band-pass filter of 365 nm was irradiated from the outside of the liquid crystal cell, and the response speed of each liquid crystal cell was compared. The measurement of the pretilt angle was performed.

As shown in Table 2, in the case of Example 15, even in the case of 7J with a small amount of ultraviolet radiation, it was confirmed that the response speed was sufficiently increased and the formation energy with a pretilt angle was confirmed. On the other hand, in Comparative Example 5, when the amount of ultraviolet irradiation was small, the pretilt angle was hardly exhibited, and it was confirmed that a large amount of ultraviolet irradiation was required to display the pretilt angle.

(Example 16)

IPDI (0.89g, 4.0mmol), DA-1 (1.32g, 4.0 mmol), DA-6 (1.52 g, 4.0 mmol), 3AMPDA (0.48 g, 2.0 mmol) were dissolved in NMP (16.0 g), and after reacting for 5 hours, CBDA (1.14 g, 5.8 mmol) and NMP (5.4 g) The mixture was reacted at room temperature for 10 hours to obtain a polyurea-amidine (PU-PAA) solution. This polymer had a Mn of 11,000 and a Mw of 28,000.

To this PU-PAA solution (26.8g), NMP (30.3g) and 3AMP (1% by mass NMP solution 5.4g) and BC (26.8g) were added to dilute to 6% by mass, followed by stirring at room temperature for 5 hours. A liquid crystal alignment agent (I1) was obtained.

Furthermore, 0.06 g of a polymerizable compound RM1 (10% by mass for solid content) was added to 10.0 g of the liquid crystal alignment agent (I1), and the liquid crystal alignment agent (I2) was prepared by stirring at room temperature for 3 hours to dissolve. .

(Example 17)

NMP (44.0g) was added to KIP150 (6.0g), and it stirred for 5 hours and was made to melt | dissolve. After adding NMP (20.0 g) and BCS (30.0 g) to this solution and diluting to 6 mass%, the polymer solution (J1) was obtained by stirring at room temperature for 5 hours.

Furthermore, 3.0 g of the polymer solution (J1) and 0.06 g of the polymerizable compound RM1 (10% by mass in terms of solid content) were added to 7.0 g of the liquid crystal alignment agent (H1) of Comparative Example 2 and stirred at room temperature for 3 hours. When the solution is dissolved in a small amount of time, the liquid crystal alignment agent (J2) is prepared.

(Example 18)

BODA (3.0, 12.0 mmol), 3AMPDA (1.45 g, 6.0 mmol), DA-6 (4.57 g, 12.0 mmol), and DA-1 (3.96 g, 12.0 mmol) were dissolved in NMP (49.4 g). After reacting at 5 ° C for 5 hours, CBDA (3.47 g, 17.7 mmol) and NMP (16.5 g) were added, and the reaction was carried out at 40 ° C for 10 hours to obtain a polyamic acid solution.

After adding NMP to this polyphosphonic acid solution (80 g) and diluting it to 6 mass%, acetic anhydride (14.8 g) and pyridine (4.6 g) were added as the imidization catalyst, and the reaction was carried out at 70 ° C for 3 hours. . This reaction solution was poured into methanol (1060 ml), and the obtained precipitate was obtained by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyfluorene imide powder (K). The polyimide has a fluorinated imidization rate of 72%, Mn of 17000, and Mw of 54,000.

NMP (44.0g) was added to the obtained polyimide powder (K) (6.0g), and it stirred at 70 degreeC for 12 hours, and was made to melt | dissolve. To this solution, 6.0 g of 3AMP (1 wt% NMP solution), NMP (14.0 g), and BCS (30.0 g) were added, and the liquid crystal alignment agent (K1) was obtained by stirring at room temperature for 5 hours.

In addition, 0.06 g of polymerizable compound RM1 (10% by mass for solid content) was added to 10.0 g of the liquid crystal alignment agent (K1), and the liquid crystal alignment agent (K2) was prepared by stirring at room temperature for 3 hours to dissolve. .

(Comparative Example 6)

BODA (3.0, 12.0 mmol), 3AMPDA (1.45 g, 6.0 mmol), DA-6 (4.57 g, 12.0 mmol), 4DABP (2.55 g, 12.0 mmol) was dissolved in NMP (45.1 g), and after reacting at 60 ° C for 5 hours, CBDA (3.47 g, 17.7 mmol) and NMP (15.5 g) were added, and the reaction was conducted at 40 ° C for 10 hours to obtain polyamino acid Solution.

After adding NMP to this polyphosphonic acid solution (70 g) and diluting to 6 mass%, acetic anhydride (14.2 g) and pyridine (4.4 g) were added as the phosphonium imidization catalyst, and the reaction was carried out at 70 ° C for 3 hours. . This reaction solution was poured into methanol (940 ml), and the obtained precipitate was obtained by filtration. This deposit was wash | cleaned with methanol, and it dried under reduced pressure at 100 degreeC, and obtained the polyfluorene imide powder (L). The polyimide has a fluorene imidization rate of 70%, Mn of 14,000, and Mw of 41,000.

NMP (44.0 g) was added to the obtained polyfluorene imine powder (L) (6.0 g), and it stirred at 70 degreeC for 12 hours, and was made to melt | dissolve. To this solution, 6.0 g of 3AMP (1 wt% NMP solution), NMP (14.0 g), and BCS (30.0 g) were added, and the liquid crystal alignment agent (L1) was obtained by stirring at room temperature for 5 hours.

Furthermore, 0.06 g of polymerizable compound RM1 (10% by mass for solid content) was added to 10.0 g of the liquid crystal alignment agent (L1), and the liquid crystal alignment agent (L2) was prepared by stirring at room temperature for 3 hours to dissolve. .

<Production and Evaluation of Liquid Crystal Cells> (Example 19)

Except that the liquid crystal alignment agent (I2) was used instead of the liquid crystal alignment agent (A1), the same operation was performed as in Example 7, and the response speed was compared before and after UV irradiation. The measurement of the pretilt angle was performed.

(Example 20)

The same operation was performed as in Example 7 except that the liquid crystal alignment agent (J2) was used instead of the liquid crystal alignment agent (A1), and the response speed was compared before and after UV irradiation. The measurement of the pretilt angle was performed.

(Example 21)

The same operation was performed as in Example 7 except that the liquid crystal alignment agent (K2) was used instead of the liquid crystal alignment agent (A1), and the response speed was compared before and after UV irradiation. The measurement of the pretilt angle was performed.

(Comparative Example 7)

The same operation was performed as in Example 7 except that the liquid crystal alignment agent (L2) was used instead of the liquid crystal alignment agent (A1), and the response speed was compared before and after UV irradiation. The measurement of the pretilt angle was performed.

From the results of Examples 19 and 20 described above, it was confirmed that even when a polymer (polyurea structure or polystyrene structure) having a main chain structure other than polyimide is used, a radical is initiated by introducing a side chain site. The part can exhibit a sufficient pretilt angle even if it is irradiated with ultraviolet rays having a long wavelength such as 365 nm.

On the other hand, as shown in Comparative Example 7, when the radical starting site is introduced into the main chain skeleton of the polymer, it can be seen that the pretilt angle can be exhibited when compared with the case where it is introduced into the side chain site. The tendency to weaken.

Generally speaking, in a polymerization reaction in which a polymerizable compound is reacted by UV irradiation to form a pretilt angle, it is thought that the interface between a liquid crystal alignment film and liquid crystal (which is in contact with the liquid crystal alignment film) is efficiently generated. Therefore, it is considered that a pre-tilt angle is formed. However, as in Comparative Example 7, when there are free radical sites in the backbone of the main chain, it is considered that the free radicals generated by ultraviolet irradiation exist in the polymer and cannot effectively participate in the reaction with the liquid crystal interface. Therefore.

[Industrial availability]

The liquid crystal alignment agent of the present invention is not only suitable as a liquid crystal display element for vertical alignment method used for manufacturing PSA type liquid crystal display, SC-PVA type liquid crystal display, etc., but also suitable for liquid crystal alignment manufactured by rubbing treatment or light alignment treatment. Use of film.

In addition, the entire contents of the specification, patent application scope, drawings, and abstract of Japanese Patent Application No. 2013-182351 filed on September 3, 2013 are incorporated herein by way of disclosure into the description of the present invention.

Claims (18)

A liquid crystal alignment agent, comprising a polyfluorene imide precursor having a side chain structure represented by the following formula (I), and a group composed of a polyfluorene imine obtained by fluorinating the precursor At least one polymer selected from the group consisting of (Ar is shown as an aromatic hydrocarbon group selected from the group consisting of phenylene, naphthyl, and biphenylyl, which may be substituted by organic groups, and hydrogen atoms may be substituted by halogen atoms; R ₁ and R ₂ are each independently carbon An alkyl group, alkoxy group, benzyl group, or phenethyl group having 1 to 10 atoms; if it is an alkyl group or alkoxy group, R ₁ and R _{2 may} form a ring; T ₁ and T ₂ are each independently a single bond , -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N (CH ₃ )-, -CON (CH ₃ )-, or -N (CH ₃ ) CO-; S is a single bond, or an unsubstituted or substituted carbon atom having 1 to 20 carbon atoms (however, -CH ₂ -or CF ₂ -of an alkylene group may be replaced by -CH = CH- substitution, and when any of the following groups are not adjacent to each other, they may be substituted by these groups: -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, A divalent carbocyclic ring or a divalent heterocyclic ring); Q is represented by the following structure, (R is shown as a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; R _{3 is} shown as -CH _2- , -NR-, -O-, or -S-). The liquid crystal alignment agent according to claim 1, wherein Ar in the formula (I) is a phenyl group and Q is -OR. The liquid crystal alignment agent according to claim 1 or 2, wherein the polymer further has a side chain that vertically aligns the liquid crystal. The liquid crystal alignment agent according to claim 3, wherein the side chain that vertically aligns the liquid crystal is at least one selected from the following formulae (II-1) and (II-2), (X ^{1 is} shown as a single bond,-(CH ₂ ) _a- (a is an integer from 1 to 15), -O-, -CH ₂ O-, -COO- or OCO-; X ^{2 is} shown as a single bond or ( CH ₂ ) _b- (b is an integer from 1 to 15); X ^{3 is} shown as a single bond,-(CH ₂ ) _c- (c is an integer from 1 to 15), -O-, -CH ₂ O-,- COO- or OCO-; X ⁴ is a divalent cyclic group selected from a benzene ring, a cyclohexane ring, and a heterocyclic ring. Any hydrogen atom on these cyclic groups may be an alkane having 1 to 3 carbon atoms. Group, alkoxy group having 1 to 3 carbon atoms, fluorinated alkyl group having 1 to 3 carbon atoms, fluorinating alkoxy group having 1 to 3 carbon atoms or fluorine atom substitution. Furthermore, X ⁴ may also be selected from steroids Divalent organic group of an organic group having 17 to 51 carbon atoms in the skeleton; X ⁵ is a divalent cyclic group selected from a benzene ring, a cyclohexane ring, and a heterocyclic ring, and any hydrogen on these cyclic groups Atoms can be substituted by alkyl groups with 1 to 3 carbon atoms, alkoxy groups with 1 to 3 carbon atoms, fluorine-containing alkyl groups with 1 to 3 carbon atoms, fluorine-containing alkoxy groups with 1 to 3 carbon atoms or fluorine atoms; n Shown as an integer from 0 to 4; X ^{6 is} shown as an alkyl group with 1 to 18 carbon atoms, a fluorine-containing alkyl group with 1 to 18 carbon atoms, an alkoxy group with 1 to 18 carbon atoms, or 1 to 18 carbon atoms Fluoroalkoxy) -X ⁷ -X ⁸ [II-2] (X ^{7 is} shown as a single bond, -O-, -CH ₂ O-, -CONH-, -NHCO-, -CON (CH ₃ )-, -N (CH ₃ ) CO-, -COO- or OCO-; X ^{8 is} shown as an alkyl group having 8 to 22 carbon atoms or a fluorine-containing alkyl group having 6 to 18 carbon atoms). The liquid crystal alignment agent according to claim 1 or 2, wherein the polymer further has a side chain including a photoreactive group in the structure. The liquid crystal alignment agent according to claim 5, wherein the structure is a side chain containing a photoreactive group and is represented by the following formula (III) or formula (IV), -R ⁸ -R ⁹ -R ¹⁰ [III ] (R ^{8 is} shown as 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-; R ⁹ is a single bond, an alkylene group having 1 to 20 carbon atoms which may be substituted by a fluorine atom, and -CH _{2 of} an alkylene group -Can be arbitrarily substituted by -CF ₂ -or -CH = CH-, when any of the following groups are not adjacent to each other, they can be substituted by these groups: -O-, -COO-, -OCO-, -NHCO- , -CONH-, -NH-, a divalent carbocyclic or heterocyclic ring; R ^{10 is} shown as a photoreactive group selected from the following formula) -Y ₁ -Y ₂ -Y ₃ -Y ₄ -Y ₅ -Y ₆ (IV) (Y _{1 is} shown as -CH _2- , -O-, -CONH-, -NHCO-, -COO-, -OCO- , -NH-, or -CO-; Y ₂ is an alkylene, divalent carbocyclic or heterocyclic ring having 1 to 30 carbon atoms, and one or more hydrogens of the alkylene, divalent carbocyclic or heterocyclic ring The atom may be substituted by a fluorine atom or an organic group; in Y ₂ , when the following groups are not adjacent to each other, -CH ₂ -may be substituted by these groups: -O-, -NHCO-, -CONH-, -COO -, -OCO-, -NH-, -NHCONH-, -CO-; Y _{3 is} shown as -CH _2- , -O-, -CONH-, -NHCO-, -COO-, -OCO-, -NH- , -CO-, or a single bond; Y _{4 is} shown as a cinnamyl group; Y ₅ is a single bond, an alkylene group having 1 to 30 carbon atoms, a divalent carbocyclic ring or a heterocyclic ring, and this alkylene group, a divalent carbocyclic ring One or more hydrogen atoms of the heterocyclic ring may be substituted by a fluorine atom or an organic group; in Y ₅ , when the following groups are not adjacent to each other, -CH ₂ -may be substituted by these groups: -O-, -NHCO-, -CONH-, -COO-, -OCO-, -NH-, -NHCONH-, -CO-; Y ₆ is a photopolymerizable group represented by acrylfluorenyl or methacrylfluorenyl). The liquid crystal alignment agent according to claim 1, wherein the polymer is a polymer containing at least one of a polyimide precursor and a polyimide obtained by imidating the precursor, and the foregoing A polyimide precursor is obtained by reacting a diamine component containing a diamine represented by the following formula (1) and a tetracarboxylic dianhydride component, (The definition of the symbol in the formula is the same as the formula (I) above). The liquid crystal alignment agent according to claim 7, wherein the polymer is a polymer further containing at least one of the following polyfluorene imide precursor and a polyfluorene imide obtained by amidating the precursor. And the polyfluorene imide precursor is obtained by reacting a diamine component containing a diamine represented by the following formula (2) with a tetracarboxylic dianhydride component, (X is the structure of the above formula [II-1] or [II-2]; n is an integer of 1 to 4). The liquid crystal alignment agent according to claim 7 or 8, wherein the polymer further contains at least one of the following polyimide precursors and polyimide obtained by imidizing the precursors. A polymer, and the polyfluorene imide precursor is obtained by reacting a diamine component containing a diamine represented by the following formula (3) or formula (4) with a tetracarboxylic dianhydride component, (The definitions of R ⁸ , R ⁹ and R ^{10 are} the same as those of the above formula (III)) (The definitions of Y1, Y2, Y3, Y4, Y5, and Y6 are the same as those in the above formula (IV)). The liquid crystal alignment agent according to claim 7 or 8, wherein the diamine represented by the above (1) is 10 mol% to 80 mol% of a full diamine component. The liquid crystal alignment agent according to claim 9, wherein the diamine represented by the above (1) is 10 mol% to 80 mol% of a full diamine component. For example, the liquid crystal alignment agent according to claim 1, wherein the liquid crystal alignment agent is a liquid crystal obtained by reacting the polymerizable compound with a polymerizable compound in a liquid crystal and / or a liquid crystal alignment film and applying ultraviolet rays while applying a voltage. Liquid crystal alignment agent for display elements. A liquid crystal alignment film is obtained from the liquid crystal alignment agent according to any one of claims 1 to 12. A liquid crystal display element comprising a liquid crystal alignment film according to claim 13. The liquid crystal display element according to claim 14, wherein the liquid crystal display element is obtained by reacting the polymerizable compound by irradiating ultraviolet rays while applying a voltage. A polymer selected from the group consisting of a polyfluorene imide precursor having a side chain structure represented by the following formula (I) and a polyfluorene imide obtained by imiminating the precursor Polymers of at least 1 (R ₁ and R ₂ are each independently an alkyl group, alkoxy group, benzyl group, or phenethyl group having 1 to 10 carbon atoms. In the case of alkyl group or alkoxy group, R ₁ and R _{2 may} form a ring; T ₁ and T ₂ are each independently a single bond, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N (CH ₃ )-,- CON (CH ₃ )-, or -N (CH ₃ ) CO-; S is a single bond, or an unsubstituted or substituted carbon atom of 1 to 20 carbon atoms (but, the alkyl group of -CH ₂ -or CF ₂ -may be substituted by -CH = CH-, and when any of the following groups are not adjacent to each other, they may be substituted by these groups: -O-, -COO-, -OCO-, -NHCO -, -CONH-, -NH-, a divalent carbocyclic ring or a divalent heterocyclic ring); Q represents the following structure, (R is shown as a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; R _{3 is} shown as -CH _2- , -NR-, -O-, or -S-). A diamine represented by the following formula (I), In the formula, R ₁ and R ₂ are each independently an alkyl group, alkoxy group, benzyl group, or phenethyl group having 1 to 10 carbon atoms. If it is an alkyl group or alkoxy group, R ₁ and R ₂ may be formed. Ring; T ₁ and T ₂ are each independently a single bond, -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, -CH ₂ O-, -N (CH ₃ )- , -CON (CH ₃ )-, or -N (CH ₃ ) CO-; S is a single bond, or an unsubstituted or substituted carbon atom of 1 to 20 carbon atoms (but, alkylene -CH ₂ -or CF ₂ -may be substituted by -CH = CH-, and when any of the following groups are not adjacent to each other, they may be substituted by these groups: -O-, -COO-, -OCO-, -NHCO-, -CONH-, -NH-, a divalent carbocyclic ring or a divalent heterocyclic ring); Q represents the following structure, R is shown as a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; R _{3 is} shown as -CH _2- , -NR-, -O-, or -S-. A diamine represented by the following formula,