TW202246470A - Liquid crystal alignment agent, liquid crystal alignment film and liquid crystal display element - Google Patents

Abstract

Provided is a liquid crystal alignment agent characterized by containing at least one polymer (A), which is selected from the group consisting of: polyimide precursors having a repeating unit (a1) represented by formula (1); and polyimides that are imidized products of the polyimide precursors. (1) In formula (1), X1represents a tetravalent organic base. Y1 is represented by formula (H) and is a divalent organic base having three or more benzene rings. (H) In formula (H), A represents a C4-C10 alkylene group. Ar1 and Ar1' each independently represent a benzene ring, a biphenyl structure or a naphthalene ring. An arbitrary hydrogen atom on the Ar1 ring and Ar1' ring may be substituted with a monovalent group.

Description

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

The invention relates to a liquid crystal alignment agent, a liquid crystal alignment film and a liquid crystal display element.

Conventionally, liquid crystal display devices have been widely used as display units of personal computers, smartphones, mobile phones, television receivers, and the like. Liquid crystal display devices, for example, include: a liquid crystal layer sandwiched between a display element substrate and a color filter substrate, pixel electrodes and common electrodes that apply an electric field to the liquid crystal layer, and an alignment film that controls the alignment of liquid crystal molecules in the liquid crystal layer , Thin film transistor (TFT) that switches the electrical signal supplied to the pixel electrode, etc. Known methods for driving liquid crystal molecules include longitudinal electric field methods such as TN method and VA method, transverse electric field methods such as IPS (In Plane Switching) method, and FFS (Fringe Field Switching) method.

At present, the most popular liquid crystal alignment film in the industry is formed by coating the surface of a film made of polyamide acid and/or polyamide imide formed on an electrode substrate with cotton , Nylon, polyester and other cloths are rubbed in one direction to produce the so-called friction treatment. Rubbing treatment is an industrially useful method that is simple and excellent in productivity. However, along with the high performance, high definition, and enlargement of liquid crystal display elements, the scratches, dust, mechanical force, and static electricity on the surface of the alignment film caused by rubbing treatment will cause inhomogeneity in the alignment treatment surface. Various problems become apparent. As an alignment treatment method instead of the rubbing treatment, there is known a photoalignment method of imparting alignment ability to liquid crystals by irradiating polarized radiation. Regarding the photo-alignment method, methods using photoisomerization reaction, photocrosslinking reaction, and photolysis reaction have been proposed (for example, refer to Non-Patent Document 1, Patent Document 1, and Patent Document 2). [Prior Art Literature] [Patent Document]

[Patent Document 1] Japanese Patent Application Laid-Open No. 9-297313 [Patent Document 2] Japanese Patent Laid-Open No. 2004-206091 [Non-patent literature]

[Non-Patent Document 1] "Liquid Crystal Photoalignment Film" Kidowaki, Ichimura, Functional Materials, November 1997, Vol.17, No.11, pages 13~22

(Problem to be solved by the invention)

The liquid crystal alignment film used in the liquid crystal display elements of the above-mentioned IPS driving method and FFS driving method needs high alignment regulation force in order to suppress image sticking (hereinafter also referred to as AC image sticking) caused by long-term AC driving. In addition, when using the photo-alignment method for alignment treatment, the amount of light exposure will become a factor affecting energy costs and production speed, so it is better to perform alignment treatment with a small amount of light exposure. However, after review by the inventors of this case, it is known that the liquid crystal alignment film that can achieve liquid crystal alignment with a small amount of light irradiation can obtain the light irradiation of the liquid crystal alignment film with a small variation (non-uniformity) of the twist angle of the liquid crystal in the liquid crystal alignment film plane. Quantitative range is narrow. Therefore, in order to achieve a larger screen of the liquid crystal display element, the liquid crystal alignment of a part of the obtained liquid crystal alignment film will become incomplete, and when the image is displayed for a long time, the brightness in the plane will vary, causing the display Concerns about declining grades.

The purpose of the present invention is to provide a liquid crystal alignment film that can obtain a liquid crystal alignment film with a small variation (inhomogeneity) in the twist angle of the liquid crystal alignment film, and expand the range of light irradiation to obtain a high-quality liquid crystal alignment film with good efficiency. The liquid crystal alignment agent, the liquid crystal alignment film obtained from the liquid crystal alignment agent, and the liquid crystal display element using the liquid crystal alignment film. In addition, the purpose is to expand the range of light exposure to obtain a liquid crystal alignment film that can suppress AC sticking, and to obtain a liquid crystal alignment agent of good quality with good efficiency, and the liquid crystal alignment obtained by the liquid crystal alignment agent. film and a liquid crystal display element using the liquid crystal alignment film. (How to solve the problem)

As a result of diligent research, the inventors of the present invention found that the above-mentioned problems can be solved by using a liquid crystal alignment agent containing a specific component, and completed the present invention. Specifically, the following matters are the gist.

A liquid crystal alignment agent, characterized by containing a polymer (A), the polymer (A) is selected from a polyimide precursor having a repeating unit (a1) represented by the following formula (1) and the polyimide At least one of the group consisting of polyimide which is an imide product of an amine precursor.

式(1)中，X ₁表示4價有機基。Y ₁係以下式(H)表示具有3個以上之苯環之2價有機基。R及Z各自獨立地表示氫原子或1價有機基。 [化2]

式(H)中，L ₁、及L _1’各自獨立地表示單鍵、-O-、-S-、-C(＝O)-、-O-C(＝O)-、或-C(＝O)-NR-(R表示氫原子或1價有機基)。 A表示碳數4~10之伸烷基。 Ar ₁、及Ar _1’各自獨立地表示苯環、聯苯結構、或萘環。Ar ₁、及Ar _1’之環上之任意氫原子亦可被1價基取代。 又，本案整份說明書中，鹵素原子可列舉氟原子、氯原子、溴原子、碘原子等，＊表示原子鍵。 (發明之效果) [chemical 1]

In formula (1), X ₁ represents a tetravalent organic group. Y ₁ is a divalent organic group having three or more benzene rings represented by the following formula (H). R and Z each independently represent a hydrogen atom or a monovalent organic group. [Chem 2]

In formula (H), L ₁ and L _1' each independently represent a single bond, -O-, -S-, -C(=O)-, -OC(=O)-, or -C(=O )-NR-(R represents a hydrogen atom or a monovalent organic group). A represents an alkylene group having 4 to 10 carbon atoms. Ar ₁ and Ar _1' each independently represent a benzene ring, a biphenyl structure, or a naphthalene ring. Any hydrogen atom on the ring of Ar ₁ and Ar _1' may be substituted by a monovalent group. In addition, in the whole specification of this case, a halogen atom includes a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, etc., and * represents an atomic bond. (Effect of Invention)

According to the present invention, it is possible to obtain a liquid crystal alignment film with a small variation (inhomogeneity) in the twist angle of the liquid crystal alignment film within the plane of the liquid crystal alignment film, and to expand the range of light irradiation and obtain a liquid crystal alignment film of good quality with good efficiency. A liquid crystal alignment agent, the liquid crystal alignment film obtained from the liquid crystal alignment agent, and a liquid crystal display element using the liquid crystal alignment film. In addition, it is possible to obtain a liquid crystal alignment agent that can obtain a liquid crystal alignment film of good quality by expanding the range of light exposure to obtain a liquid crystal alignment film capable of suppressing AC image sticking, and the liquid crystal alignment film obtained from the liquid crystal alignment agent. And a liquid crystal display element using the liquid crystal alignment film.

＜Polymer (A)＞ The liquid crystal alignment agent of the present invention is composed of a polyimide precursor selected from a polyimide precursor having a repeating unit (a1) represented by the following formula (1) and a polyimide compound of the polyimide precursor At least one polymer (A) in the group of . Moreover, a polymer (A) may consist of 1 type, or 2 or more types.

式(1)中，X ₁表示4價有機基。Y ₁係以下式(H)表示且具有3個以上之苯環之2價有機基。R及Z各自獨立地表示氫原子或1價有機基。 [Chem 3]

In formula (1), X ₁ represents a tetravalent organic group. Y ₁ is a divalent organic group represented by the following formula (H) and having three or more benzene rings. R and Z each independently represent a hydrogen atom or a monovalent organic group.

The polymer (A) preferably has a divalent organic group represented by the above formula (H) in the main chain direction of the polymer (A). Also, the polymer (A) preferably has a benzene ring possessed by Y ₁ in the main chain direction of the polymer (A). The main chain of a polymer refers to the part composed of the longest atomic chain in the polymer. Moreover, "the polymer (A) has a divalent organic group represented by the above formula (H) in the direction of the main chain of the polymer (A)" means the longest atomic chain system among the divalent organic groups represented by the formula (H) It constitutes the main chain of the polymer (A). In other words, "the polymer (A) has a divalent organic group represented by the above formula (H) in the direction of the main chain of the polymer (A)" means the two sides of the longest atomic chain of the divalent organic group represented by the formula (H). The ends are respectively bonded to 2 nitrogen atoms bonded to Y ₁ in formula (1). Also, it means that at least 2 carbon atoms of each benzene ring among all the benzene rings possessed by _Y1 constitute the main chain of the polymer (A).

Here, the benzene ring of the "divalent organic group having three or more benzene rings" includes a benzene ring constituting a condensed ring. And when the number of benzene rings in the formula (H) is counted, it is counted as follows. The naphthalene ring system has 2 benzene rings. The biphenyl structure has 2 benzene rings. The number of benzene rings in _Y1 is not particularly limited if it is 3 or more, and may be, for example, 3 or more and 8 or less, or 3 or more and 6 or less. Considering the viewpoint of obtaining the effects of the present invention ideally, there may be 4 or more and 6 or less.

式(H)中，L ₁、及L _1’各自獨立地表示單鍵、-O-、-S-、-C(＝O)-、-O-C(＝O)-、或-C(＝O)-NR-(R表示氫原子或1價有機基。)。 A表示碳數4~10之伸烷基，更佳為碳數4、6、8、或10之伸烷基，又更佳為碳數4或6之伸烷基。 Ar ₁、及Ar _1’各自獨立地表示苯環、聯苯結構、或萘環。Ar ₁、及Ar _1’之環上之任意氫原子亦可被1價基取代。 [chemical 4]

In formula (H), L ₁ and L _1' each independently represent a single bond, -O-, -S-, -C(=O)-, -OC(=O)-, or -C(=O )-NR-(R represents a hydrogen atom or a monovalent organic group.). A represents an alkylene group having 4 to 10 carbons, more preferably an alkylene group having 4, 6, 8, or 10 carbons, and more preferably an alkylene group having 4 or 6 carbons. Ar ₁ and Ar _1' each independently represent a benzene ring, a biphenyl structure, or a naphthalene ring. Any hydrogen atom on the ring of Ar ₁ and Ar _1' may be substituted by a monovalent group.

The monovalent organic group of R in the group "-C(=O)-NR-" in L ₁ and L _1' mentioned above includes alkyl having 1 to 3 carbons, alkoxy having 1 to 3 carbons, Alkenyl with 2~3 carbons, acyl with 2~3 carbons, alkylsilyl with 1~3 carbons, alkoxysilyl with 1~3 carbons, tertiary butoxycarbonyl, or the A monovalent organic group in which a part of hydrogen atoms possessed by an isogroup is substituted by at least one of a halogen atom and a hydroxyl group.

Ar ₁ in the above formula (H) and the substituent of any hydrogen atom on the ring of Ar _1' are monovalent groups, which include halogen atoms, alkyl groups with 1 to 3 carbon atoms, and at least a part of the hydrogen atoms described above An alkyl group with 1 to 3 carbon atoms substituted by at least one of a halogen atom and a hydroxyl group; an alkoxy group with 1 to 3 carbon atoms, at least a part of the hydrogen atoms is substituted by at least one of the above halogen atoms and hydroxyl groups Alkoxy group with 1~3 carbons; alkenyl group with 2~3 carbons; acyl group with 2~3 carbons; alkylsilyl group with 1~3 carbons, alkoxysilyl group with 1~3 carbons , hydroxyl, nitrile and other monovalent groups.

If the ideal specific examples of the group "*-L ₁ -AL _1' -*" in the above formula (H) are mentioned, it can be listed: the group "*-(CH ₂ ) _n -*", the group "*-O-( CH ₂ ) _n -O-*", group "*-C(=O)-(CH ₂ ) _n -C(=O)-*", group "*-C(=O)-NR-(CH ₂ ) _n -O-*", group "*-OC(=O)-(CH ₂ ) _n -O-*", group "*-OC(=O)-(CH ₂ ) _n -OC(=O) -*", group "*-OC(=O)-(CH ₂ ) _n -C(=O)-O-*", group "*-S-(CH ₂ ) _n -S-*", group " *-C(=O)-NR-(CH ₂ ) _n -NR-C(=O)-*”, group “*-C(=O)-O-(CH ₂ ) _n -OC(=O) -*", group "*-O-(CH ₂ ) _n -*", group "*-S-(CH ₂ ) _n -*", or group "*-NR-C(=O)-(CH ₂ ) _n -C(=O)-NR-*” (R represents a hydrogen atom or a 1-valent organic group, and the 1-valent organic group can include the above-mentioned groups of L ₁ and L _1′ “-C(=O)-NR -"'s R example structure.). Among them, in view of obtaining the effect of the present invention ideally, the above-mentioned group "*-L ₁ -AL _1' -*" is the group "*-(CH ₂ ) _n -*", the group "*-O- (CH ₂ ) _n -O-*" and the group "*-O-(CH ₂ ) _n -*" are preferred. n is an integer of 4-10, preferably an integer of 4, 6, 8, or 10, more preferably an integer of 4 or 6.

式(h-1)~(h-4)中，R _a1~R _a4表示1價有機基。其具體例可列舉作為上式(H)中之Ar ₁、及Ar _1’之環上之氫原子之取代基例示之結構。L表示上式(H)之基「＊-L ₁-A-L _1’-＊」(＊表示原子鍵。)。 m各自獨立地為0~6之整數，n各自獨立地為0~4之整數。R _a1~R _a4有多個存在時，各自可相同也可不同。 Y ₁ in the above formula (1) is preferably a divalent organic group represented by any one of the following formulas (h-1) to (h-4) from the viewpoint of ideally obtaining the effect of the present invention. [chemical 5]

In the formulas (h-1) to (h-4), R _a1 to R _a4 represent monovalent organic groups. Specific examples thereof include structures exemplified as substituents for hydrogen atoms on the rings of Ar ₁ and Ar _1′ in the above formula (H). L represents the group "*-L ₁ -AL _1' -*" of the above formula (H) (* represents an atomic bond.). m is each independently an integer of 0-6, and n is each independently an integer of 0-4. When a plurality of R _a1 to R _a4 exist, each may be the same or different.

In the above formula (1), the monovalent organic groups of R and Z include: monovalent hydrocarbon groups with 1 to 20 carbons, and the methylene groups of the hydrocarbon groups are replaced by -O-, -S-, -CO-, - COO-, -COS-, -NR ³ -, -CO-NR ³ -, -Si(R ³ ) ₂ - (except that R ³ is a hydrogen atom or a monovalent hydrocarbon group with 1 to 10 carbons.), -SO ₂ - At least one of the resulting monovalent group A, the above-mentioned monovalent hydrocarbon group, or the hydrogen atom bonded to the carbon atom of the above-mentioned monovalent group A is replaced by a halogen atom, hydroxyl, alkoxy, nitro, amino, Mercapto, nitroso, alkylsilyl, alkoxysilyl, silanol, sulfinic acid, phosphino, carboxyl, cyano, sulfo, acyl, etc., with a heterocycle One of the valence bases. In the above formula (1), the monovalent organic groups of R and Z are alkyl with 1 to 10 carbons, alkenyl with 2 to 10 carbons, alkynyl with 2 to 10 carbons, tertiary butoxy A carbonyl group or a 9-fenylmethoxycarbonyl group is more preferable, an alkyl group having 1 to 3 carbon atoms is more preferable, and a methyl group is more preferable. R and Z are each independently preferably a hydrogen atom or an alkyl group having 1 to 3 carbons, and more preferably a hydrogen atom or a methyl group, in view of ideally obtaining the effect of the present invention.

For the above-mentioned polymer (A), considering the viewpoint of ideally obtaining the effect of the present invention, it may also be a polyimide precursor selected from a repeating unit (a2) represented by the following formula (2) and the polyimide At least one polymer of the group consisting of polyimides of imides of imine precursors. In other words, the above-mentioned polymer (A) may further have at least any one of the repeating unit (a2) represented by the following formula (2) and the imidized structure of the repeating unit (a2) represented by the following formula (2). Moreover, the repeating unit (a2) may consist of 1 type or 2 or more types.

式(2)中，X ₂表示4價有機基。Y ₂表示下式(o-1)~(o-14)表示之2價有機基。R、及Z各和上式(1)之R、及Z為同義。 [chemical 6]

In formula (2), X ₂ represents a tetravalent organic group. Y ₂ represents a divalent organic group represented by the following formulas (o-1) to (o-14). R, and Z are each synonymous with R, and Z in the above formula (1).

[化8]

式(o-13)~式(o-14)中，2個m各自獨立。式(o-1)~(o-14)中之苯環、聯苯結構或萘環之環上之任意氫原子也可被1價基取代。 [chemical 7]

[chemical 8]

In the formula (o-13) to the formula (o-14), the two ms are independent of each other. Any hydrogen atom on the benzene ring, biphenyl structure or naphthalene ring in the formulas (o-1)~(o-14) can also be substituted by a monovalent group.

The substituent of any hydrogen atom on the benzene ring, biphenyl structure or naphthalene ring in the formulas (o-1)~(o-14) is a monovalent group, which can include: halogen atom, carbon number 1~3 An alkyl group, an alkyl group in which at least a part of the hydrogen atoms are substituted by at least any one of the above-mentioned halogen atoms and hydroxyl groups; an alkoxy group having 1 to 3 carbon atoms, at least a part of the hydrogen atoms being replaced by at least one of the above-mentioned halogen atoms and hydroxyl groups One is substituted alkoxy group; alkenyl group with 2~3 carbons; acyl group with 2~3 carbons; alkylsilyl group with 1~3 carbons, alkoxysilyl group with 1~3 carbons, hydroxyl , nitrile group and other monovalent groups.

式(2’)、及式(3)中，X _2’、及X ₃表示4價有機基，Y _2’表示下式(O2)表示之2價有機基，Y ₃表示分子內具有基「-N(D)-(D表示胺甲酸酯系保護基。)」之碳數6~30之2價有機基。R、及Z各和上式(1)之R、及Z為同義。 [化10]

式(O2)中，m表示0~2之整數。m為0時，Ar _2’表示苯環或萘環，m為1~2時，Ar _2’各自獨立地表示苯環。Ar _2’之環上之任意氫原子也可被1價基取代，該取代基可列舉在上式(o-1)~(o-14)中之苯環、聯苯結構或萘環之任意氫原子之取代基即1價基例示之結構。Q _2’表示單鍵、或-O-。Ar _2’、及Q _2’有多個存在時，多個Ar _2’、及Q _2’各自可相同也可不同。 With regard to the above-mentioned polymer (A), considering the viewpoint of ideally obtaining the effects of the present invention, it may be selected from the group consisting of repeating units (a2') represented by the following formula (2') and represented by the following formula (3). A polyimide precursor of at least one of the group consisting of repeating units (a3) and at least one polymerization of the group consisting of polyimides which are imides of the polyimide precursor thing. In other words, the above-mentioned polymer (A) may further have the repeating unit (a2') represented by the following formula (2'), the imidized structure of the repeating unit (a2') represented by the following formula (2'), the following formula At least any one of the repeating unit (a3) represented by (3) and the imidization structure of the repeating unit (a3) represented by the following formula (3). [chemical 9]

In formula (2') and formula (3), X _2' and X ₃ represent a 4-valent organic group, Y _2' represents a divalent organic group represented by the following formula (O2), and Y ₃ represents a group in the molecule " -N(D)-(D represents a carbamate-based protecting group.)" is a divalent organic group with 6 to 30 carbon atoms. R, and Z are each synonymous with R, and Z in the above formula (1). [chemical 10]

In the formula (O2), m represents an integer of 0-2. When m is 0, Ar _2' represents a benzene ring or a naphthalene ring, and when m is 1 to 2, Ar _2' each independently represent a benzene ring. Any hydrogen atom on the Ar _2' ring can also be substituted by a monovalent group. The substituent can be any of the benzene ring, biphenyl structure or naphthalene ring in the above formulas (o-1)~(o-14). The substituent of the hydrogen atom is the structure exemplified by the monovalent group. Q _2' represents a single bond, or -O-. When a plurality of Ar 2 _' and Q 2 _' exist, each of the plurality of Ar _2' and Q _2' may be the same or different.

For the divalent organic group represented by the above formula (O2), considering the occurrence of less AC sticking, it is selected from p-phenylenediamine, m-phenylenediamine, 2,5-diaminotoluene, 2,5- Diamino-p-xylene, 1,4-diaminotrimethylbenzene, 1,4-diaminotetramethylbenzene, 1,4-diamino-2,5-methoxybenzene, 3, 3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-dimethyl-4,4'-diamine 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 2,2'- Dimethoxy-4,4'-diaminobiphenyl, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 2,2'-dihydroxy-4,4'-diamine Biphenyl, 3,3'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl Benzene, 3-trifluoromethyl-4,4'-diaminobiphenyl, 2-trifluoromethyl-4,4'-diaminobiphenyl, 3-fluoro-4,4'-diaminobiphenyl Biphenyl, 2-fluoro-4,4'-diaminobiphenyl, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, The diamine in the group consisting of 2,6-diaminonaphthalene and 1,5-diaminonaphthalene is preferably a divalent organic group in which two amine groups have been removed.

D in _Y3 above represents a carbamate-based protecting group, such as tert-butoxycarbonyl or 9-tertilylmethoxycarbonyl. Specific examples of the aforementioned Y ₃ include divalent organic groups represented by the following formula (Dx).

[chemical 11]

In formula (Dx), Q ₅ represents a single bond, -(CH ₂ ) _n -(n is an integer from 1 to 20), or any -CH ₂ - of -(CH ₂ ) _n - by -O-, - Si(CH ₃ ) ₂ -, -COO-, -OCO-, -NQ ₉ -, -NQ ₉ CO-, -CONQ ₉ -, -NQ ₉ CONQ ₁₀ -, -NQ ₉ COO- or -OCOO- Q ₉ and Q ₁₀ each independently represent a hydrogen atom or a monovalent organic group; Q ₆ and Q ₇ each independently represent -H, -NHD, -N(D) ₂ , a base with -NHD, or a base with - The base of N(D) ₂ (D represents a carbamate-based protecting group.). However, when m=0, Q ₆ has a carbamate protecting group, and when m=1, at least one of Q ₅ , Q ₆ and Q ₇ has a carbamate protecting group among the groups. Also, when Q ₆ and Q ₇ represent a group other than a hydrogen atom, the ideal carbon number is 1-8. The monovalent organic groups of Q ₉ and Q ₁₀ mentioned above include alkyl groups with 1 to 3 carbons, alkenyl groups with 2 to 3 carbons, alkynyl groups with 2 to 3 carbons, and 1 to 3 carbons containing fluorine atoms. 1-valent organic group.

Regarding the ideal specific example of _Y3 , considering the viewpoint of less afterimage of AC, a divalent organic group represented by any one of the following formulas (Y3-1) to (Y3-9) can be mentioned. "Boc" means tert-butoxycarbonyl.

[chemical 12]

For the above-mentioned X ₁ , X ₂ , X _2′ , and X ₃ , there may be mentioned those derived from acyclic aliphatic tetracarboxylic dianhydride or derivatives thereof, alicyclic tetracarboxylic dianhydride or derivatives thereof, or aromatic A tetravalent organic group of tetracarboxylic dianhydride or derivatives thereof. Here, derivatives of tetracarboxylic dianhydride include, for example, tetracarboxylic acid dihalides, tetracarboxylic acid dialkyl esters, and tetracarboxylic acid dialkyl ester dihalides. Among them, the tetravalent organic group derived from tetracarboxylic dianhydride or derivatives thereof having at least one substructure selected from the group consisting of cyclobutane ring structure, cyclopentane ring structure and cyclohexane ring structure is more ideal. If _the ideal specific examples of X ₁ , X ₂ , X _2' , and X ₃ are mentioned, in addition to the tetravalent organic group represented by the following formula (g), the following formulas (X-1)~(X-25) can also be listed. A tetravalent organic group represented by any of them, a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride, and the like. Considering the viewpoint of obtaining the effect of the present invention ideally, X ₁ , X ₂ , X _2' and X ₃ are the following formulas (g), (X-1)~(X-5), (X-11), (X The tetravalent organic group represented by -21)~(X-23) is more preferable, and the tetravalent organic group represented by the following formula (g) is more preferable.

式(g)中，R ₁~R ₄各自獨立地表示氫原子、鹵素原子、碳數1~6之烷基、碳數2~6之烯基、碳數2~6之炔基、含有氟原子之碳數1~6之1價有機基、或苯基，R ₁~R ₄中之至少一者表示上述定義中之氫原子以外之基。 [chemical 13]

In formula (g), R ₁ to R ₄ each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbons, an alkenyl group having 2 to 6 carbons, an alkynyl group having 2 to 6 carbons, a fluorine-containing A monovalent organic group with 1 to 6 carbon atoms, or a phenyl group, at least one of R ₁ to R ₄ represents a group other than a hydrogen atom as defined above.

[化15]

[chemical 14]

[chemical 15]

Specific examples of alkyl groups having 1 to 6 carbon atoms in R ₁ to R ₄ in the above formula (g) include methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, second Butyl, tertiary butyl, n-pentyl, etc. Specific examples of alkenyl groups having 2 to 6 carbon atoms in the above R ₁ to R ₄ include vinyl, propenyl, butynyl, etc., which may be linear or branched. Specific examples of the above-mentioned alkynyl groups having 2 to 6 carbon atoms in R ₁ to R ₄ include ethynyl, 1-propynyl, 2-propynyl and the like. Examples of monovalent organic groups having 1 to 6 carbon atoms containing fluorine atoms for R ₁ to R ₄ include fluoromethyl, trifluoromethyl, pentafluoroethyl, and pentafluoropropyl. A more ideal combination of R ₁ ~ R ₄ , considering the viewpoint of high photoreactivity, preferably R ₁ ~ R ₄ is a hydrogen atom or a methyl group and at least one of R ₁ ~ R ₄ is preferably a methyl group, and R It is more preferable that at least two of ₁ to R ₄ are methyl groups. Still more preferably, R ₁ and R ₄ are methyl groups and R ₂ and R ₃ are hydrogen atoms.

Here, the aromatic tetracarboxylic dianhydride refers to an acid dianhydride obtained by intramolecular dehydration of a carboxyl group bonded to an aromatic ring such as a benzene ring or a naphthalene ring. If specific examples are given, any of the tetravalent organic groups represented by any of the following formulas (Xa-1) to (Xa-2), and any of the following formulas (Xr-1) to (Xr-7) Represents a 4-valent organic group.

式(Xa-1)及(Xa-2)中，x及y各自獨立地為單鍵、醚、羰基、酯、碳數1~10之烷二基、1,4-伸苯基、磺醯基或醯胺鍵。j及k為0或1之整數。 [chemical 16]

In formulas (Xa-1) and (Xa-2), x and y are each independently a single bond, ether, carbonyl, ester, alkanediyl with 1 to 10 carbons, 1,4-phenylene, sulfonyl group or amide bond. j and k are integers of 0 or 1.

[chemical 17]

The tetravalent organic group represented by the above formula (Xa-1) or (Xa-2) may also have a structure represented by any one of the following formulas (Xa-3) to (Xa-19).

[chemical 18]

[chemical 19]

The above-mentioned polymer (A) may also be selected from having the above-mentioned repeating unit (a1), repeating unit (a2), repeating unit (a2'), and repeating unit (a3) and further having the following formula (4) At least one polymer selected from the group consisting of a polyimide precursor of the repeating unit (a4) and a polyimide which is an imidized product of the polyimide precursor.

[chemical 20]

In formula (4), X ₄ represents a 4-valent organic group, Y ₄ represents a divalent organic group represented by the above formula (H), a divalent organic group represented by the above formula (o-1)~(o-14), and a molecule A divalent organic group with 6 to 30 carbon atoms having the above-mentioned group "-N(D)-(D represents a carbamate-based protecting group.)" and a divalent organic group other than the divalent organic group represented by the above formula (O2) 2-valent organic group. R, and Z are each synonymous with R, and Z in the above formula (1).

Specific examples of X ₄ include the tetravalent organic groups exemplified in the description of X ₁ , X ₂ , X _2′ , and X ₃ above. Considering the viewpoint of obtaining the effect of the present invention ideally, X ₄ is a 4-valent organic group represented by the above formula (g), or a 4-valent organic group represented by any one of the above formulas (X-1) to (X-25). The group is ideal, the quaternary organic group represented by the above formula (g), (X-1)~(X-5), (X-11), (X-21)~(X-23) is better, the above formula The tetravalent organic group represented by (g) is more preferable.

Y ₄ represents the divalent organic group represented by the above formula (H), the divalent organic group represented by the above formula (o-1)~(o-14), and the above-mentioned group "-N(D)-(D represents Urethane-based protecting group.)" divalent organic groups with 6 to 30 carbon atoms, and divalent organic groups other than the divalent organic groups represented by the above formula (O2) (hereinafter also referred to as other divalent organic groups ), and the other divalent organic groups include divalent organic groups obtained by removing two amine groups from the following diamines. Can be listed from 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diaminodiphenylmethane ; diamines represented by the following formulas (g-1)~(g-10) and other diamines with photoalignment groups; diamines represented by the following formulas (u-1)~(u-3) and other diamines with urea bonds Diamine (provided that the diamine does not have a urethane-based protecting group in the molecule); diamines represented by the following formulas (u-4)~(u-8) and other diamines with amide bonds (except that the diamine Diamine does not have a urethane-based protecting group in the molecule.); has a heterocyclic ring selected from a nitrogen-containing atom, and a group "* ₂₁ -NR-* ₂₂ " (* ₂₁ , and * ₂₂ represent and constitute aromatic The atomic bond bonded by the carbon atom of the ring. However, the carbon atom does not form a ring with the nitrogen atom bonded by R. R represents a hydrogen atom or a monovalent organic group, and the above monovalent organic group consists of carbon atoms other than carbonyl carbon and nitrogen At least one nitrogen atom-containing structure (hereinafter also referred to as a nitrogen atom-containing structure) in the group consisting of amine groups represented by diamine; 3,5-diaminobenzyl alcohol, 2, 4-Diaminobenzyl alcohol; 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, 4,4'-diaminobiphenyl-3 -carboxylic acid, 4,4'-diaminodiphenylmethane-3-carboxylic acid, 4,4'-diaminodiphenylethane-3-carboxylic acid, 4,4'-diaminobiphenyl Benzene-3,3'-dicarboxylic acid, 4,4'-diaminobiphenyl-2,2'-dicarboxylic acid, 3,3'-diaminobiphenyl-4,4'-dicarboxylic acid , 3,3'-diaminobiphenyl-2,4'-dicarboxylic acid, 4,4'-diaminodiphenylmethane-3,3'-dicarboxylic acid, 4,4'-diamine Diamines with carboxyl groups such as diphenylethane-3,3'-dicarboxylic acid and 4,4'-diaminodiphenyl ether-3,3'-dicarboxylic acid; 4-(2-(methyl Amino)ethyl)aniline, 4-(2-aminoethyl)aniline, 4,4'-diaminodiphenylketone, 1-(4-aminophenyl)-1,3,3- Trimethyl-1H-inden-5-amine, 1-(4-aminophenyl)-2,3-dihydro-1,3,3-trimethyl-1H-inden-6-amine; 2-(2,4-diaminophenoxy)ethyl methacrylate and 2,4-diamino-N,N-diallylaniline and other diamines with photopolymerizable groups at the end; cholesteric acid Alkyloxy-3,5-diaminobenzene, cholestenyloxy-3,5-diaminobenzene, cholestanyloxy-2,4-diaminobenzene, 3,5- Cholesteryl diaminobenzoate, cholestenyl 3,5-diaminobenzoate, lanostyl 3,5-diaminobenzoate and 3,6-bis(4-aminobenzyl Diamines with a steroid skeleton such as acyloxycholestane; diamines represented by the following formulas (V-1)~(V-6); 1,3-bis(3-aminopropyl)-tetramethyldiamine Diamines with siloxane bonds such as siloxane; diamines with oxazoline ring structure such as the following formula (Ox-1)~(Ox-2); 1-(4-(2,4-diamino Phenoxy) Ethoxy) Phenyl)-2-hydroxy-2-methylacetone, 2-(4-(2-hydroxy-2-methylpropionyl)phenoxy)ethyl-3,5-diaminobenzoate , 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, and other diamines that have the function of radical polymerization initiators. An organic group, a group represented by any one of the formulas (Y-1) to (Y-167) described in WO2018/117239.

[化22]

[化23]

[chem 21]

[chem 22]

[chem 23]

In the above formulas (V-1) to (V-6), X ^v1 to X ^v4 and X ^p1 to X ^p2 each independently represent -(CH ₂ ) _a -(a is an integer of 1 to 15.), - CONH-, -NHCO-, -CO-N(CH ₃ )-, -NH-, -O-, -CH ₂ O-, -CH ₂ -OCO-, -COO-, or -OCO-, X ^v5 means -O-, _-CH2O- , _-CH2 -OCO-, -COO-, or -OCO-. X _a represents a single bond, -O-, -NH-, -O-(CH ₂ ) _m -O- (m represents an integer from 1 to 6.), -C(CH ₃ ) ₂ -, -CO-, - (CH ₂ ) _m -(m represents an integer from 1 to 6.), -SO ₂ -, -OC(CH ₃ ) ₂ -, -CO-(CH ₂ ) _m -(m represents an integer from 1 to 6.) , -NH-(CH ₂ ) _m -(m represents an integer from 1 to 6.), -SO ₂ -(CH ₂ ) _m -(m represents an integer from 1 to 6.), -CONH-(CH ₂ ) _m -(m represents an integer of 1~6.), -CONH-(CH ₂ ) _m -NHCO-(m represents an integer of 1~6.), -COO-(CH ₂ ) _m -OCO-(m represents 1~ Integer of 6.), -CONH-, -NH-(CH ₂ ) _m -NH-(m represents an integer of 1 to 6.), or -SO ₂ -(CH ₂ ) _m -SO ₂ -(m represents 1 ~6 integers.), R ^v1 ~R ^v4 , and R ^1a ~ R ^1b each independently represent an alkyl group with 1 to 20 carbons, an alkoxy group with 1 to 20 carbons, or an alkoxy group with 2 to 20 carbons base alkyl.

[chem 24]

Heterocyclic rings containing the above-mentioned nitrogen atoms, such as: pyrrole, imidazole, pyrazole, triazole, pyridine, pyrimidine, pyridine, pyridine, indole, benzimidazole, purine, quinoline, isoquinoline, pyridine, quinol㗁line, phthalein, tris, carbazole, acridine, piperidine, piperidine, pyrrolidine, hexamethyleneimine, etc. Among them, pyridine, pyrimidine, pyridine, piperidine, piperidine, quinoline, carbazole or acridine are preferred.

The monovalent organic group of R in the above-mentioned group "* ₂₁ -NR-* ₂₂ " represents a monovalent hydrocarbon group with 1 to 10 carbons, and -O- or -C (= O)-a monovalent group formed, or a monovalent organic group in which part of the hydrogen atoms possessed by the above-mentioned hydrocarbon group and the above-mentioned monovalent group is replaced by a halogen atom or a hydroxyl group. R is preferably a hydrogen atom or a methyl group.

[化26]

[化27]

Specific examples of diamines with structures containing nitrogen atoms, such as: 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminocarba Azole, N-methyl-3,6-diaminocarbazole, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, 1,4 -Bis-(4-aminophenyl)-piperone, 3,6-diaminoacridine, compounds represented by the following formula (Dp-1)~(Dp-8), or the following formula (z-1) ~ the compound represented by formula (z-13). [chem 25]

[chem 26]

[chem 27]

Considering the viewpoint of ideally obtaining the effects of the present invention, the above-mentioned other divalent organic groups are preferably divalent organic groups that do not have a side chain structure with a carbon number of 4 or more. A valent organic group can be exemplified: a divalent organic group with two amine groups removed from the following diamines, that is, a divalent organic group selected from the group consisting of 2-(2,4-diaminophenoxy methacrylic acid from the other diamines mentioned above) ) ethyl ester, 2,4-diamino-N,N-diallylaniline, the above-mentioned diamines having a steroid skeleton, diamines represented by the above formulas (V-1)~(V-6), 1- (4-(2-(2,4-diaminophenoxy)ethoxy)phenyl)-2-hydroxy-2-methylacetone, 2-(4-(2-hydroxy-2-methyl Propyl)phenoxy)ethyl-3,5-diaminobenzoate, N-phenyl-3,6-diaminocarbazole, (z-4) and (z-6) "Diamine in the group consisting of diamines such as diamines" is a divalent organic group in which two amine groups have been removed.

Considering the viewpoint of obtaining the effects of the present invention ideally, in the polymer (A), the total content of the repeating unit (a1) and the imidized structure of the repeating unit (a1) is 5 to 100 mol% of the total repeating unit. Good, preferably 10~100 mole %. In addition, the sum here also includes the case where either one of the repeating unit (a1) and the imidization structure of the repeating unit (a1) is 0 mol%. Hereinafter, when referred to as "total", the case where 1 or more of the constituent elements are 0 mol% is also included. When the polymer (A) contains repeating units other than the repeating unit (a1) and the imidization structure of the repeating unit (a1), in the polymer (A), the repeating unit (a1) and the imidization structure of the repeating unit (a1) The total content of the aminated structure is preferably not more than 95 mol%, more preferably not more than 90 mol%, and more preferably not more than 80 mol%, of all repeating units.

Considering the ideal effect of the present invention, in the polymer (A), the total content of the repeating unit (a2) and the imidized structure of the repeating unit (a2) is preferably 5 mol% or more of the total repeating units , more than 10 mol%, more preferably 20 mol% or more. Also, the upper limit thereof is preferably 90 mol%, more preferably 85 mol%.

Considering that the effects of the present invention are ideally obtained, in the polymer (A), the total content of the repeating unit (a1) and the repeating unit (a2) and their imidized structures is 10 mol% or more of the total repeating units Preferably, more than 20 mol%. When the polymer (A) contains repeating units (a1) and repeating units (a2) and repeating units other than their imidized structures, the repeating units (a1) and repeating units (a2) and their imidized structures The upper limit of the total content is preferably 95 mol%, more preferably 90 mol%.

When the polymer (A) contains at least any one of the repeating unit (a2') and the imidized structure of the repeating unit (a2'), considering that the effect of the present invention is ideally obtained, in the polymer (A) The total content of the repeating unit (a2') and the imidized structure of the repeating unit (a2') is preferably 1-50 mol% of the total repeating unit, more preferably 1-40 mol%, 1-30 mol% Ear% is even better. When the polymer (A) contains at least any one of the repeating unit (a1) and its imidized structure, and at least any one of the repeating unit (a2') and its imidized structure, the repeating unit ( The lower limit of the total content of a1), repeating unit (a2') and their imidized structures is preferably 5 mol%, more preferably 10 mol%. From the viewpoint of ideally obtaining the effects of the present invention, the polymer (A) contains at least any one of the repeating unit (a1) and its imidized structure, the repeating unit (a2) and its imidized structure At least any one of, and at least any one of the repeating unit (a2') and its imidization structure, and the repeating unit (a1), repeating unit (a2) and repeating unit (a2') and their acyl The total content of imidized structures is preferably 30 mol% or more of all repeating units, more preferably 40 mol% or more. When the polymer (A) contains repeating units (a1), repeating units (a2) and repeating units (a2') and repeating units other than their imidized structures, repeating units (a1), repeating units (a2) and The upper limit of the total content of the repeating unit (a2') and their imidized structures is preferably 95 mol%, more preferably 90 mol%.

When the polymer (A) contains at least any one of the repeating unit (a3) and the imidization structure of the repeating unit (a3), considering the ideal effect of the present invention, the repeating in the polymer (A) The total content of the imidized structure of the unit (a3) and the repeating unit (a3) is preferably 1-40 mol%, more preferably 1-30 mol%, and more preferably 1-25 mol% of the total repeating unit good.

The polymer (A) may contain at least any one of repeating unit (a2'), repeating unit (a3), and their imidized structures.

式(5)中，X ₅為4價有機基，Y ₅為2價有機基。R、及Z各和上式(1)之R、及Z為同義。 <Polymer (B)> The liquid crystal alignment agent of the present invention may contain, in addition to the above-mentioned polymer (A), a polymer (B) that does not have the above-mentioned repeating unit (a1) and its imidized structure in the molecule. . Moreover, a polymer (B) may consist of 1 type, or 2 or more types. From the viewpoint of ideally obtaining the effect of the present invention, examples of the polymer (B) include a repeating unit represented by the following formula (5) or a polymer having an imidized structure thereof. In addition, the repeating unit constituting the polymer (B) or its imidized structure may be composed of one type or two or more types. [chem 28]

In formula (5), X ₅ is a tetravalent organic group, and Y ₅ is a divalent organic group. R, and Z are each synonymous with R, and Z in the above formula (1).

_The tetravalent organic group of the above-mentioned X5 includes a tetravalent organic group derived from acyclic aliphatic tetracarboxylic dianhydride or a derivative thereof, a tetravalent organic group derived from an alicyclic tetracarboxylic dianhydride or a derivative thereof Or a tetravalent organic group derived from an aromatic tetracarboxylic dianhydride or _a derivative thereof. Specific examples include the tetravalent organic group exemplified above for X1. Considering the viewpoint of obtaining the effect of the present invention ideally, among the above-mentioned non-cyclic aliphatic or alicyclic tetracarboxylic dianhydrides or their derivatives, and considering the high effect of improving the liquid crystal alignment, there are selected from cyclobutyl Tetracarboxylic dianhydride or derivatives thereof of at least one substructure in the group consisting of an alkane ring structure, a cyclopentane ring structure and a cyclohexane ring structure are preferred. A more desirable X5 is a quaternary organic group represented by the above formula (g), a ₄ -valent organic group represented by any one of the above formulas (X-1) to (X-25), a 4-valent organic group represented by the above formula (Xa-1) 4-valent organic groups represented by ~(Xa-2) or 4-valent organic groups represented by the above formulas (Xr-1)~(Xr-7) (they are also collectively referred to as specific 4-valent organic groups.).

For the polymer (B), considering the viewpoint of obtaining the effects of the present invention ideally, X ₅ is the repeating unit represented by the formula (5) of the above-mentioned specific 4-valent organic group or the content of the imidized structure of the polymer is preferably The total repeating units contained in (B) are preferably 5 mol% or more, more preferably 10 mol% or more.

The divalent organic group of the above-mentioned Y ₅ includes the divalent organic groups exemplified in the above-mentioned Y ₄ . In consideration of less image sticking from residual DC, the polymer (B) is preferably a diamine containing Y5 from the above _- mentioned diamine having a urea bond, the above-mentioned diamine having an amide bond, or the above-mentioned diamine having a structure containing a nitrogen atom. , 2,4-diaminobenzyl alcohol, 3,5-diaminophenol, 3,5-diaminobenzyl alcohol, 2,4-diaminobenzyl alcohol, 4,6-diaminoresorcinol , the above-mentioned diamines with carboxyl groups, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 3,3'-dimethyl-4,4'-diamine Diphenylmethane, p-phenylenediamine, and m-phenylenediamine are divalent organic groups with two amino groups removed (they are also collectively referred to as specific divalent organic groups.) The repeating unit represented by formula (5) or its A polymer having an imidized structure is preferable.

The polymer (B) has two or more repeating units represented by the above formula (5) or its imidized structure from the viewpoint of improving the transmittance, and contains a diamine having a urea bond from the above, the above-mentioned A diamine having an amide bond, or a diamine having a structure containing a nitrogen atom mentioned above is a repeating unit represented by the formula (5) of Y ₅ and its imidization structure. At least any one of them, and at least any one of the repeating unit represented by the formula (5) having a divalent organic group with two amine groups removed from other diamines, that is, Y ₅ , and its imidization structure is more preferable .

Regarding the polymer (B), considering the viewpoint of less image sticking due to residual DC, Y5 is the total content of the repeating unit represented by the formula ( ₅ ) of the above-mentioned specific divalent organic group and its imidized structure, which can be The total repeating units contained in the polymer (B) may be 1 mol% or more, and may be 5 mol% or more. More preferably, it is at least 10 mol%, and more preferably at least 20 mol%.

Considering the viewpoint of less image sticking from residual DC, the content ratio of polymer (A) and polymer (B) in the liquid crystal alignment agent is based on the mass ratio of [polymer (A)]/[polymer (B)] It can be 10/90~90/10, 20/80~90/10, or 20/80~80/20.

<Manufacturing method of polyamide acid, polyamide ester and polyimide> The polyamide esters, polyamide acids, and polyimides that are polyimide precursors used in the present invention can be known, for example, as described in WO2013/157586. method synthesis.

式[D-1]中，D ¹表示碳數1~3之烷基，式[D-2]中，D ²表示碳數1~3之烷基，式[D-3]中，D ³表示碳數1~4之烷基。 More specifically, it implement|achieves by carrying out (condensation polymerization) reaction of a diamine component, and a tetracarboxylic-acid derivative component in a solvent. As the said tetracarboxylic-acid derivative component, tetracarboxylic dianhydride and derivatives thereof (tetracarboxylic dihalide, tetracarboxylic diester, or tetracarboxylic diester dihalide) are mentioned. When a part of the polymer (A) or (B) contains an amide acid structure, for example, by reacting a tetracarboxylic dianhydride component with a diamine component, a polymer (polyamic acid) having an amide acid structure is obtained . The solvent is not particularly limited as long as it dissolves the polymer to be formed. Specific examples of the above-mentioned solvents include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, γ-butyrolactone, N,N-dimethylformamide, N,N-dimethylacetamide Amide, dimethylsulfoxide, 1,3-dimethyl-2-imidazolidinone. Also, when the solvent solubility of the polymer is high, methyl ethyl ketone, cyclohexanone, cyclopentanone, 4-hydroxy-4-methyl-2-pentanone, or the following formula [D-1] ~ formula [D- 3] The solvent indicated. [chem 29]

In formula [D-1], D ¹ represents an alkyl group with 1 to 3 carbons; in formula [D-2], D ² represents an alkyl group with 1 to 3 carbons; in formula [D-3], D ³ Indicates an alkyl group with 1 to 4 carbon atoms.

These solvents may be used alone or in combination. In addition, even if it is a solvent in which a polymer does not dissolve, it can be mixed with the said solvent and used in the range which the produced polymer does not precipitate. When reacting the diamine component and the tetracarboxylic acid derivative component in a solvent, the reaction can be performed at any concentration, preferably 1 to 50% by mass, more preferably 5 to 30% by mass. The reaction may be carried out at a high concentration in the initial stage, and a solvent may be added thereafter. During the reaction, the ratio of the total number of moles of the diamine components to the total number of moles of the tetracarboxylic acid derivative components is preferably 0.8 to 1.2. Similar to the usual polycondensation reaction, the closer the molar ratio is to 1.0, the larger the molecular weights of the polymer (A) and polymer (B) produced will be.

Polyamic acid ester can be obtained by, for example: [I] a method of reacting the polyamic acid obtained by the above method with an esterifying agent, [II] a method of reacting a tetracarboxylic acid diester with a diamine, [III] It can be obtained by a known method such as a method of reacting a tetracarboxylic diester dihalide with a diamine.

As a method for obtaining polyimide, known methods such as thermal imidization in which the polymer solution obtained by the above reaction is directly heated, or catalytic imidization in which a catalyst is added to the polymer solution can be mentioned.

The polyimide in the polymer (A) and the polymer (B) of the present invention is part or all of the repeating units of the polyimide precursor mentioned above that are ring-closed. Among the above polyimides, the imidization rate is preferably 20-95%, more preferably 30-95%, more preferably 50-95%.

<Polymer solution viscosity, molecular weight> The polyamic acid, polyamic acid ester and polyimide used in the present invention, when made into a solution with a concentration of 10-15% by mass, for example, have a solution viscosity of 10-1000mPa·s from the viewpoint of workability Ideal, but no special restrictions. In addition, the solution viscosity (mPa·s) of the above-mentioned polymer is obtained by using a good solvent for the polymer (such as: γ-butyrolactone, N-methyl-2-pyrrolidone, etc.) to prepare a concentration of 10-15 mass%. Polymer solution, the value measured at 25°C using an E-type rotational viscometer. The weight average molecular weight (Mw) in terms of polystyrene as measured by gel permeation chromatography (GPC) of the above-mentioned polyamic acid, polyamic acid ester, and polyimide is preferably 1,000 to 500,000, more preferably 2,000 to 500,000. 300,000. Also, the molecular weight distribution (Mw/Mn) represented by the ratio of Mw to the polystyrene-equivalent number average molecular weight (Mn) measured by GPC is preferably 15 or less, more preferably 10 or less. By being in such a molecular weight range, good alignment and stability of the liquid crystal display element can be ensured.

＜Blocking agent＞ When synthesizing the polymers (A) and (B) of the present invention, the above-mentioned tetracarboxylic acid derivative components, diamine components, and appropriate end-capping agents can be used to synthesize end-sealed polymers. End-sealed polymers have the effects of improving the film hardness of the liquid crystal alignment film obtained from the coating film and improving the adhesion between the sealant and the liquid crystal alignment film. The terminals of the polymer (A) and polymer (B) in the present invention are, for example, amino groups, carboxyl groups, acid anhydride groups, or groups derived from end-capping agents described later. Amino groups, carboxyl groups, and acid anhydride groups can be obtained by a common condensation reaction, or by sealing the ends with the following blocking agents.

Capping agents, such as: acetic anhydride, maleic anhydride, nedylic anhydride, phthalic anhydride, itaconic anhydride, cyclohexanedicarboxylic anhydride, 3-hydroxyphthalic anhydride, trimellitic anhydride, 3- (3-trimethoxysilyl)propyl)-3,4-dihydrofuran-2,5-dione, 4,5,6,7-tetrafluoroisobenzofuran-1,3-dione, Acid monoanhydrides such as 4-ethynyl phthalic anhydride; di-tert-butyl dicarbonate, diallyl dicarbonate and other dicarbonate diester compounds; acryl chloride, methacryl chloride, nicotinyl chloride, etc. Chlorocarbonyl compounds; aniline, 2-aminophenol, 3-aminophenol, 4-aminosalicylic acid, 5-aminosalicylic acid, 6-aminosalicylic acid, 2-aminobenzoic acid, 3 -Aminobenzoic acid, 4-aminobenzoic acid, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine and other monoamine compounds; ethyl isocyanate, benzene isocyanate Monoisocyanate compounds such as esters, naphthyl isocyanate, 2-acryloxyethyl isocyanate and 2-methacryloxyethyl isocyanate and other isocyanates with unsaturated bonds; ethyl isothiocyanate, isothiocyanate Isothiocyanate compounds such as allyl acrylate, etc.

The usage ratio of the end-capping agent is preferably 0.01-20 mole parts, more preferably 0.01-10 mole parts, relative to the total 100 mole parts of the diamine components used.

＜Liquid crystal alignment agent＞ The liquid crystal alignment agent of the present invention contains a polymer (A) and optionally a polymer (B). The liquid crystal alignment agent of the present invention may also contain other polymers besides polymer (A) and polymer (B). Specific examples of other polymers include polysiloxanes, polyesters, polyamides, polyureas, polyurethanes, polyorganosiloxanes, cellulose derivatives, polyacetals, and polyamides. Styrene derivatives, poly(styrene-maleic anhydride) copolymers, poly(isobutylene-maleic anhydride) copolymers, poly(vinyl ether-maleic anhydride) copolymers, poly(styrene-phenylmaleic anhydride) imine) derivatives, polymers in the group consisting of poly(meth)acrylates, etc. Specific examples of poly(styrene-maleic anhydride) copolymers include SMA1000, 2000, and 3000 (manufactured by Cray Valley Co.), GSM301 (manufactured by GIFUSHELLAC Manufacturing Co., Ltd.), and specific examples of poly(isobutylene-maleic anhydride) copolymers Examples include ISOBAM-600 (manufactured by Kuraray Co., Ltd.), and specific examples of poly(vinyl ether-maleic anhydride) copolymers include Gantrez AN-139 (methyl vinyl ether maleic anhydride resin, manufactured by ASHLAND). Other polymers may be used alone or in combination of two or more. The proportion of other polymers is preferably not more than 90 parts by mass, more preferably 10 to 90 parts by mass, and more preferably 20 to 80 parts by mass, based on 100 parts by mass of the total polymers contained in the liquid crystal alignment agent.

The liquid crystal alignment agent is used for making a liquid crystal alignment film, and it takes the form of a coating liquid in consideration of forming a uniform thin film. The liquid crystal alignment agent of the present invention is also preferably a coating solution containing the above-mentioned polymer component and an organic solvent. At this time, the concentration of the polymer in the liquid crystal alignment agent can be appropriately changed according to the setting of the thickness of the coating film to be formed. From the viewpoint of forming a uniform and defect-free coating film, the concentration of the polymer in the liquid crystal alignment agent is preferably 1% by mass or more, and from the viewpoint of storage stability of the solution, it is preferably 10% by mass or less. In particular, the concentration of the ideal polymer is 2 to 8% by mass.

The organic solvent contained in the liquid crystal alignment agent is not particularly limited as long as the polymer components are uniformly dissolved. Specific examples thereof include N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethyllactamide, N,N-dimethylacrylamide, tetra Methylurea, N,N-diethylformamide, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethylsulfoxide, γ-butyrolactone, γ-valerolactone , 1,3-Dimethyl-2-imidazolidinone, methyl ethyl ketone, cyclohexanone, cyclopentanone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N, N-Dimethylpropanamide, N-(n-propyl)-2-pyrrolidone, N-isopropyl-2-pyrrolidone, N-(n-butyl)-2-pyrrolidone, N-(tert-butyl )-2-pyrrolidone, N-(n-pentyl)-2-pyrrolidone, N-methoxypropyl-2-pyrrolidone, N-ethoxyethyl-2-pyrrolidone, N-methoxybutyl- 2-pyrrolidone, N-cyclohexyl-2-pyrrolidone (these are also collectively referred to as "good solvent"). Among them, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 3-methoxy-N,N-dimethylpropanamide, 3-butoxy-N,N-dimethyl Propanamide or γ-butyrolactone is preferred. The content of the good solvent is preferably 20-99% by mass, more preferably 20-90% by mass, and most preferably 30-80% by mass of the total solvent contained in the liquid crystal alignment agent.

In addition, the organic solvent contained in the liquid crystal alignment agent should be mixed with a solvent (also known as a poor solvent) to improve the coatability and surface smoothness of the coating film in addition to the above-mentioned solvents. . The content of the poor solvent is preferably 1 to 80% by mass, more preferably 10 to 80% by mass, and most preferably 20 to 70% by mass, of the entire solvent contained in the liquid crystal alignment agent. The type and content of the poor solvent can be properly selected according to the liquid crystal alignment agent coating device, coating conditions, coating environment, etc. Specific examples of poor solvents used together are as follows but not limited thereto. For example: diisopropyl ether, diisobutyl ether, diisobutylmethanol (2,6-dimethyl-4-heptanol), ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, 1,2-dibutoxyethane, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, 4-hydroxy-4-methyl-2-pentanone, diethylene glycol methyl ether, Diethylene glycol dibutyl ether, 3-ethoxybutyl acetate, 1-methylpentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, ethylene diacetate Alcohol monoacetate, ethylene glycol diacetate, propylene carbonate, ethylene carbonate, ethylene glycol monobutyl ether, ethylene glycol monoisopentyl ether, ethylene glycol monohexyl ether, propylene glycol monomethyl ether , propylene glycol monobutyl ether, 1-(2-butoxyethoxy)-2-propanol, 2-(2-butoxyethoxy)-1-propanol, propylene glycol monomethyl ether acetate, Propylene glycol diacetate, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monobutyl ether acetate, diethylene glycol monopropyl ether, diethylene glycol monoethyl ether acetate , Diethylene glycol monobutyl ether acetate, 2-(2-ethoxyethoxy) ethyl acetate, diethylene glycol acetate, propylene glycol diacetate, n-butyl acetate, acetic acid Propylene glycol monoethyl ether, cyclohexyl acetate, 4-methyl-2-pentyl acetate, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 3-methoxypropionate, 3-methoxypropyl propionate, 3-methoxybutyl propionate, n-butyl lactate, isoamyl lactate, diethylene glycol monoethyl ether, diisobutyl ketone (2,6-dimethyl -4-heptanone), etc.

Among them, diisobutylmethanol, propylene glycol monobutyl ether, propylene glycol diacetate, diethylene glycol diethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol dimethyl ether, 4-hydroxyl-4-methyl-2 - Pentanone, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, or diisobutyl ketone are preferred.

The combination of ideal solvents for good solvents and poor solvents can include: N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether, N-methyl-2-pyrrolidone and γ-butyrolactone and ethylene glycol monobutyl ether ether, N-methyl-2-pyrrolidone and γ-butyrolactone and propylene glycol monobutyl ether, N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether, N-ethyl-2-pyrrolidone and 4-hydroxy-4 -Methyl-2-pentanone, N-ethyl-2-pyrrolidone and propylene glycol diacetate, N,N-dimethyl lactamide and diisobutyl ketone, N-methyl-2-pyrrolidone and Ethyl 3-ethoxypropionate, N-ethyl-2-pyrrolidone and ethyl 3-ethoxypropionate, N-methyl-2-pyrrolidone and ethyl 3-ethoxypropionate and dipropylene glycol Monomethyl ether, N-ethyl-2-pyrrolidone and ethyl 3-ethoxypropionate and propylene glycol monobutyl ether, N-methyl-2-pyrrolidone and ethyl 3-ethoxypropionate and diethylene glycol Alcohol monopropyl ether, N-ethyl-2-pyrrolidone and ethyl 3-ethoxypropionate and diethylene glycol monopropyl ether, N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether acetate , N-ethyl-2-pyrrolidone and dipropylene glycol dimethyl ether, N,N-dimethyl lactamide and ethylene glycol monobutyl ether, N,N-dimethyl lactamide and propylene glycol diacetate , N-ethyl-2-pyrrolidone and diethylene glycol diethyl ether, N-ethyl-2-pyrrolidone and diethylene glycol monoethyl ether and butyl cellothracetate, N-methyl-2-pyrrolidone Diethylene glycol monomethyl ether and butyl cellothracetate, N,N-dimethyl lactamide and diethylene glycol diethyl ether, N-methyl-2-pyrrolidone and γ-butyrolactone With 4-hydroxy-4-methyl-2-pentanone and diethylene glycol diethyl ether, N-ethyl-2-pyrrolidone and N-methyl-2-pyrrolidone and 4-hydroxy-4-methyl-2 -pentanone, N-ethyl-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone and propylene glycol monobutyl ether, N-methyl-2-pyrrolidone and 4-hydroxy-4-methyl- 2-pentanone and diisobutyl ketone, N-methyl-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone and dipropylene glycol monomethyl ether, N-methyl-2-pyrrolidone and 4 -Hydroxy-4-methyl-2-pentanone and propylene glycol monobutyl ether, N-methyl-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone and propylene glycol diacetate, N-ethyl Base-2-pyrrolidone and 4-hydroxy-4-methyl-2-pentanone and dipropylene glycol dimethyl ether, γ-butyrolactone and 4-hydroxy-4-methyl-2-pentanone and diisobutyl Ketone, γ-butyrolactone and 4-hydroxy-4-methyl-2-pentanone and propylene glycol diacetate, N-methyl-2-pyrrolidone and γ-butyrolactone and propylene glycol monobutyl ether and diiso Butyl ketone, N-methyl-2-pyrrolidone and γ-butyrolactone and propylene glycol monobutyl ether and diisopropyl ether, N-methyl-2-pyrrolidone and γ-butyrolactone and propylene glycol monobutyl ether and diisopropyl ether Isobutyl carbinol, N-methyl-2-pyrrolidone and γ-butyrolactone and dipropylene glycol dimethyl ether, N-methyl-2-pyrrolidone and propylene glycol monobutyl ether and dipropylene glycol dimethyl ether, N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether and dipropylene glycol monomethyl ether, N-ethyl-2-pyrrolidone and diethylene glycol diethyl ether and dipropylene glycol monomethyl ether, N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether and propylene glycol diacetate, N-ethyl-2-pyrrolidone and propylene glycol monobutyl ether and diisobutyl ketone, N-ethyl-2-pyrrolidone and γ-butyrolactone and diisobutyl Base ketone, N-ethyl-2-pyrrolidone and N,N-dimethyl lactamide and diisobutyl ketone, N-methyl-2-pyrrolidone and ethylene glycol monobutyl ether and ethylene glycol monobutyl Ether acetate, γ-butyrolactone and ethylene glycol monobutyl ether acetate and dipropylene glycol dimethyl ether, N-ethyl-2-pyrrolidone and ethylene glycol monobutyl ether acetate and propylene glycol dimethyl ether , N-methyl-2-pyrrolidone and 4-methyl-2-pentyl acetate and ethylene glycol monobutyl ether, N-ethyl-2-pyrrolidone and cyclohexyl acetate and diacetone alcohol cyclohexanone and propylene glycol Monomethyl ether, cyclopentanone and propylene glycol monomethyl ether, N-methyl-2-pyrrolidone, cyclohexanone and propylene glycol monomethyl ether, etc.

The liquid crystal alignment agent of the present invention may additionally contain components other than polymer components and organic solvents (hereinafter also referred to as additive components). Examples of such additive components include: adhesion aids for improving the adhesion between the liquid crystal alignment film and the substrate, the adhesion between the liquid crystal alignment film and the sealant, and compounds for improving the strength of the liquid crystal alignment film (hereinafter Also known as cross-linking compounds), compounds used to promote imidization, dielectrics used to adjust the dielectric constant and resistance of liquid crystal alignment films, conductive substances, etc.

The above-mentioned crosslinkable compound may be at least one compound selected from the group consisting of: , epoxypropylene group, protected isocyanate group, protected isothiocyanate group, group containing zozoline ring structure, group containing Meldrum's acid structure, ring carbonate group and hydroxyalkylamide bond A compound of at least one group in the group consisting of, and a phenol compound having at least one of an alkoxymethyl group and a hydroxymethyl group.

Specific examples of compounds having an oxirane group include: 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, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol di Bisphenol A epoxy resins such as glycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, EPIKOTE828 (manufactured by Mitsubishi Chemical Corporation), EPIKOTE807 (manufactured by Mitsubishi Chemical Corporation) ) and other bisphenol F-type epoxy resins, YX-8000 (manufactured by Mitsubishi Chemical Corporation) and other hydrogenated bisphenol A-type epoxy resins, YX6954BH30 (manufactured by Mitsubishi Chemical Corporation) and other epoxy resins containing a biphenyl skeleton, EPPN-201 ( Nippon Kayaku Co., Ltd.) and other phenol novolac epoxy resins, EOCN-102S (Nippon Kayaku Co., Ltd.) and other (ortho, meta, para) cresol novolac epoxy resins, TEPIC (Nissan Chemical Corporation) Triglycidyl isocyanurate, etc., CELLOXIDE 2021P (manufactured by Daicel Chemical Industry Co., Ltd.) and other alicyclic epoxy resins, N,N,N',N'-tetraglycidyl-m-xylylenediamine , 1,3-bis(N,N-diepoxypropylaminomethyl)cyclohexane, N,N,N',N'-tetraepoxypropyl-4,4'-diaminodiphenyl Methane, tetrakis(glycidoxymethyl)methane.

Specific examples of the compound having a propylene oxide group include compounds having two or more propylene oxide groups described in paragraphs [0170] to [0175] of WO2011/132751.

Specific examples of compounds having protected isocyanate groups include compounds having two or more protected isocyanate groups described in paragraphs [0046] to [0047] of JP-A-2014-224978 and paragraphs of WO2015/141598 [0119]～[0120] The compound etc. with more than 3 protected isocyanate groups described in the record, commercially available products such as can ideally use CORONATE AP Stable M, CORONATE2503, 2515, 2507, 2513, 2555, MILLIONATE MS-50 (above manufactured by Tosoh Corporation), TAKENATE B-830, B-815N, B-820NSU, B-842N, B-846N, B-870N, B-874N, B-882N (the above are manufactured by Mitsui Chemicals Corporation), etc.

Specific examples of compounds having protected isothiocyanate groups include compounds having two or more protected isothiocyanate groups described in JP-A-2016-200798. Specific examples of compounds having a group having a oxazoline ring structure include compounds containing two or more oxazoline ring structures described in paragraph [0115] of JP-A-2007-286597. Specific examples of compounds having a group having a Michaelis acid structure include compounds having two or more Michaelis acid structures described in WO2012/091088. As a specific example of the compound which has a cyclocarbonate group, the compound described in WO2011/155577 is mentioned.

R ₂及R ₃各自獨立地為氫原子、碳數1~3之烷基或「＊-CH ₂-OH」。 Specific examples of the above compound having a hydroxyalkylamide bond include groups having two or more groups represented by the following formula (d) as described in WO2015/072554 and paragraph [0058] of JP-A-2016-118753. Compounds, compounds described in Japanese Patent Application Laid-Open No. 2016-200798, etc. [chem 30]

R ₂ and R ₃ are each independently a hydrogen atom, an alkyl group having 1 to 3 carbons, or "*-CH ₂ -OH".

Specific examples of the above-mentioned phenol compound having at least one of an alkoxyalkyl group and a hydroxymethyl group include compounds described in WO2010/074269.

The above-mentioned compound is an example of a crosslinkable compound and is not limited thereto. For example: ingredients other than the above disclosed on page 53 [0105] to page 55 [0116] of WO2015/060357. Moreover, you may combine 2 or more types of crosslinkable compounds.

Among the above-mentioned cross-linking compounds, N,N,N',N'-tetraglycidyl-m-xylylenediamine, 1,3-bis(N,N-diecidylaminomethyl)cyclohexane , N,N,N',N'-tetraepoxypropyl-4,4'-diaminodiphenylmethane, TAKENATE B-830, B-815N, B-820NSU, B-842N, B-846N , B-870N, B-874N, B-882N, 1,3,5-ginseng (2-hydroxyethyl) isocyanurate, triglycidyl isocyanurate, N,N,N ',N'-tetra(2-hydroxyethyl)adipamide, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)propane, 2,2-bis(4-hydroxy -3,5-dimethoxymethylphenyl)propane, 2,2-bis(4-hydroxy-3,5-dihydroxymethylphenyl)-1,1,1,3,3,3- Hexafluoropropane is preferred.

In the liquid crystal alignment agent of the present invention, the content of the cross-linking compound is preferably 0.5 to 20 parts by mass relative to 100 parts by mass of the polymer component contained in the liquid crystal alignment agent, considering that the cross-linking reaction proceeds and the AC sticking effect is good. From the viewpoint of tolerance, it is more preferably 1 to 15 parts by mass.

The above adhesion aids, such as 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-aminopropyldiethoxymethylsilane, 2-aminopropyl Trimethoxysilane, 2-aminopropyltriethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)- 3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyl Trimethoxysilane, Vinyltrimethoxysilane, Vinyltriethoxysilane, 2-(3,4-Epoxycyclohexyl)ethyltrimethoxysilane, 3-Glycidoxypropylmethyl Dimethoxysilane, 3-Glycidoxypropyltrimethoxysilane, 3-Glycidoxypropylmethyldiethoxysilane, 3-Glycidoxypropyltriethoxy Silane, p-Styryltrimethoxysilane, 3-Methacryloxypropylmethyldimethoxysilane, 3-Methacryloxypropyltrimethoxysilane, 3-Methacryl Oxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-acryloxypropyltrimethoxysilane, ginseng (trimethoxysilylpropyl ) isocyanurate, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-isocyanatepropyltriethoxysilane and other silane coupling agents. When a silane coupling agent is used, it is preferably 0.1 to 30 parts by mass, more preferably 0.1 to 20 parts by mass, based on 100 parts by mass of the polymer component contained in the liquid crystal alignment agent, in consideration of exhibiting good resistance to AC image sticking.

D表示因加熱而脫離之有機基，較佳為第三丁氧基羰基、或9-茀基甲氧基羰基。 The above-mentioned compounds for promoting imidization include: having a basic site (for example: first-level amino group, aliphatic heterocycle (for example: pyrrolidine skeleton), aromatic heterocycle (for example: imidazole ring, indol Inole ring), or guanidino group, etc.) (excluding the above-mentioned cross-linking compounds and adhesion aids), or compounds that generate the above-mentioned basic sites during calcination are preferred. More preferably, it is a compound that generates the above-mentioned basic site during calcination, and specific examples include compounds represented by the following formulas (B-1) to (B-17). The content of the compound for promoting imidization is preferably 2 mole parts or less, more preferably 1 mole part with respect to 1 mole part of the amino acid or amido ester moiety possessed by the polymer (A). It is less than an ear part, more preferably less than 0.5 molar part. [chem 31]

D represents an organic group detached by heating, preferably tert-butoxycarbonyl or 9-tertilylmethoxycarbonyl.

The solid content concentration in the liquid crystal alignment agent (the ratio of the total mass of the components other than the solvent of the liquid crystal alignment agent to the total mass of the liquid crystal alignment agent) can be appropriately selected in consideration of viscosity, volatility, etc., preferably 1 to 10 mass % range.

The particularly desirable range of solid content concentration varies depending on the method used when coating the liquid crystal alignment agent on the substrate. For example, when the spin coating method is used, the solid content concentration is particularly preferably in the range of 1.5 to 4.5% by mass. When using the printing method, the solid content concentration is in the range of 3 to 9% by mass, and the viscosity of the solution is preferably in the range of 12 to 50 mPa·s. When using the inkjet method, the solid content concentration is in the range of 1 to 5% by mass, and the viscosity of the solution is preferably in the range of 3 to 15 mPa·s. The temperature for preparing the polymer composition is preferably 10-50°C, more preferably 20-30°C.

＜Liquid crystal alignment film, liquid crystal display element＞ The liquid crystal alignment film of the present invention is obtained from the above-mentioned liquid crystal alignment agent. The liquid crystal alignment film of the present invention can be used in horizontal alignment type or vertical alignment type (VA type) liquid crystal alignment film, among which, it is a liquid crystal alignment film suitable for horizontal alignment type liquid crystal display elements such as IPS method or FFS method. In addition, the liquid crystal alignment film of the present invention is more suitable for use as a liquid crystal alignment film for photo-alignment treatment. In addition, the liquid crystal alignment film of the present invention can be effectively used in various technical purposes, such as liquid crystal alignment films other than the above-mentioned purposes (liquid crystal alignment film for retardation film, scanning antenna, liquid crystal alignment film for liquid crystal array antenna or transmission scattering type Liquid crystal alignment film for liquid crystal dimming elements), or other uses, such as: protective film (for example: protective film for color filters), spacer film, interlayer insulating film, anti-reflection film, wiring coating film, Antistatic film, motor insulation film (gate insulation film for flexible displays), etc. The liquid crystal display element of the present invention includes the above-mentioned liquid crystal alignment film. The liquid crystal display element of the present invention can be manufactured by, for example, a method including the following steps (1) to (3). The liquid crystal display element of the present invention can be manufactured, for example, by a method including the following steps (1) to (3) and (5) or steps (1) to (2) and (5). More preferably, it is produced by a method comprising steps (1) to (5).

<Step (1): The step of coating the liquid crystal alignment agent on the substrate> Step (1) is a step of coating the liquid crystal alignment agent of the present invention on the substrate. The specific example of step (1) is as follows. The liquid crystal alignment agent of the present invention is coated on one side of the substrate provided with the patterned transparent conductive film by appropriate coating methods such as roll coating method, spin coating method, printing method, and inkjet method. Here, the substrate is not particularly limited as long as it is highly transparent, and a plastic substrate such as a glass substrate, a silicon nitride substrate, an acrylic substrate, or a polycarbonate substrate may be used together. In addition, if the reflective liquid crystal display element has only one side substrate, opaque objects such as silicon wafers can also be used, and the electrodes at this time can also use materials that reflect light such as aluminum. Also, when manufacturing IPS-type or FFS-type liquid crystal display elements, a substrate provided with electrodes made of a comb-shaped transparent conductive film or metal film and an opposite substrate without electrodes are used.

The method of coating the liquid crystal alignment agent on the substrate and forming a film includes screen printing, offset printing, flexographic printing, inkjet method, or spraying method. Among them, the coating and film-forming methods by the inkjet method are preferable.

<Step (2): The step of calcining the coated liquid crystal alignment agent> Step (2) is a step of calcining the liquid crystal alignment agent coated on the substrate to form a film. The specific example of step (2) is as follows. After coating the liquid crystal alignment agent on the substrate in step (1), the solvent can be evaporated by means of heating such as a hot plate, a thermal cycle oven, or an IR (infrared) oven, or polyamide acid or polyamide Thermal imidization of esters. The drying and calcining steps after coating the liquid crystal alignment agent of the present invention can be performed at any temperature and time, and can also be performed multiple times. Calcination temperature can be performed at, for example, 40-180°C. Considering the viewpoint of shortening treatment, it can also be carried out at 40~150°C. The calcination time at this time is not particularly limited, for example, 1 to 10 minutes or 1 to 5 minutes. When performing thermal imidization of polyamic acid or polyamic acid ester, after the above-mentioned step of removing the organic solvent, a step of calcining at a temperature range of 150-300°C or 150-250°C can be added. The calcination time at this time is not particularly limited, and may be 5 to 40 minutes or 5 to 30 minutes. If the calcined film is too thin, sometimes the reliability of the liquid crystal display element will be reduced, so 5~300nm is more ideal, and 10~200nm is more ideal.

<Step (3): Steps of Alignment Processing> Step (3) is a step of performing alignment treatment on the calcined film (coating film) obtained in step (2) as the case may be. That is, in a liquid crystal display element of a horizontal alignment type such as an IPS system or an FFS system, an alignment ability imparting process is applied to the coating film. On the other hand, in a vertical alignment type liquid crystal display element such as VA mode or PSA mode, the formed coating film can be used as a liquid crystal alignment film as it is, but the coating film can also be subjected to alignment ability imparting treatment. The alignment treatment methods of the liquid crystal alignment film include rubbing treatment and photo-alignment treatment, and photo-alignment treatment is more ideal. The photo-alignment treatment method can include irradiating the surface of the above-mentioned membranous object with radiation deflected in a certain direction, and depending on the situation, preferably heat treatment at a temperature of 150-250°C, and endows liquid crystal alignment (also known as liquid crystal alignment). alignment ability) method. As the radiation, ultraviolet rays or visible rays having a wavelength of 100 to 800 nm can be used. Among them, ultraviolet rays having a wavelength of 100 to 400 nm are preferable, and ultraviolet rays having a wavelength of 200 to 400 nm are more preferable.

The irradiation dose of the above-mentioned radiation is ideally 1~10,000mJ/cm ² , more preferably 100~5,000mJ/cm ² , more ideally 100~1,500mJ/cm ² , more preferably 100~1,000mJ/cm ² , 100~400mJ / ^cm2 is more ideal. When using a common liquid crystal alignment agent, the amount of light irradiation in the alignment treatment is 100~5,000mJ/cm ² , but the liquid crystal alignment agent of the present invention can obtain liquid crystals in the surface of the liquid crystal alignment film even if the light irradiation amount of the alignment treatment is reduced. A liquid crystal alignment film in which alignment variation (non-uniformity) is suppressed.

Moreover, when irradiating radiation, in order to improve liquid crystal alignment, you may irradiate while heating the said board|substrate which has a membranous thing at 50-250 degreeC. The above-mentioned liquid crystal alignment film manufactured in this way can make the liquid crystal molecules align stably along a certain direction. Also, the liquid crystal alignment film irradiated with polarized radiation by the above method may be subjected to contact treatment with water or a solvent, or the liquid crystal alignment film irradiated with radiation may be heat-treated.

The solvent used in the above-mentioned contact treatment is not particularly limited as long as it dissolves the decomposed product generated from the film-like material by irradiation with radiation. Specific examples include water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, 1-methoxy-2-propanol, 1-methoxy-2-propanol acetate, butylcylonol, Ethyl lactate, methyl lactate, diacetone alcohol, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl acetate, butyl acetate, cyclohexyl acetate, etc. Among them, water, 2-propanol, 1-methoxy-2-propanol, or ethyl lactate are preferable from the viewpoint of versatility and safety of the solvent. More preferred are water, 1-methoxy-2-propanol or ethyl lactate. A solvent may be used alone or in combination of two or more.

<Step (4): The step of heat treatment> Step (4) is a step of heat-treating the liquid crystal alignment film that has been aligned in step (3). Heat treatment may also be performed on the above-mentioned irradiated film (coating film) irradiated with radiation. The temperature for heat treatment of the coating film irradiated with radiation is preferably 50-300°C, more preferably 120-250°C. The heat treatment time is preferably 1 to 30 minutes.

＜Step (5): Steps for making liquid crystal cells＞ Two substrates on which the liquid crystal alignment film was formed as described above were prepared, and liquid crystals were arranged between the two substrates facing each other. Specifically, the following two methods can be mentioned. In the first method, first, two substrates are arranged facing each other with a gap (cell gap) in such a manner that the respective liquid crystal alignment films face each other. Then, the peripheral parts of the two substrates are bonded together using a sealant, and the liquid crystal composition is injected into the cell gap partitioned by the substrate surface and the sealant to make contact with the film surface, and then the injection hole is sealed.

Also, the second method is a method called ODF (One Drop Fill) method. On one of the two substrates on which the liquid crystal alignment film has been formed, apply, for example, a UV-curable sealant on predetermined positions, and then drop liquid crystal composition on several predetermined positions on the surface of the liquid crystal alignment film. Then, with the liquid crystal alignment film facing the other substrate, the liquid crystal composition is pushed out on the entire surface of the substrate to make it contact with the film surface. Then, the entire surface of the substrate is irradiated with ultraviolet light to harden the sealant. When using either method, it is more heated until the liquid crystal composition used becomes the temperature of the isotropic phase, and then slowly cooled to room temperature to remove the flow alignment when filling the liquid crystal is ideal. In addition, when rubbing the coating film, two substrates are arranged facing each other so that the rubbing directions of the respective coating films form a predetermined angle, for example, perpendicularly or antiparallel. As the sealing agent, for example, an epoxy resin containing a hardener and alumina balls as spacers can be used. The above-mentioned liquid crystal composition is not particularly limited, and various liquid crystal compositions containing at least one liquid crystal compound (liquid crystal molecule) and having positive or negative dielectric anisotropy can be used. Hereinafter, a liquid crystal composition having a positive dielectric anisotropy is also referred to as a positive type liquid crystal, and a liquid crystal composition having a negative dielectric anisotropy is also referred to as a negative type liquid crystal. Examples of the liquid crystal composition include a liquid crystal composition in a nematic phase, a liquid crystal composition in a smectic phase, and a liquid crystal composition in a cholesteric phase. Among them, a liquid crystal composition in a nematic phase is preferred. The above-mentioned liquid crystal composition may also contain fluorine atoms, hydroxyl groups, amino groups, groups containing fluorine atoms (for example: trifluoromethyl), cyano groups, alkyl groups, alkoxy groups, alkenyl groups, isothiocyanate groups, Liquid crystal compounds of heterocycles, cycloalkanes, cycloalkenes, steroid skeletons, benzene rings, or naphthalene rings may also contain compounds with two or more rigid sites (mesogen skeletons) exhibiting liquid crystallinity in the molecule (such as : Two straight biphenyl structures, or a double mesogen compound formed by linking a terphenyl structure with an alkyl group). In the above-mentioned liquid crystal composition, additives may be further added in consideration of improving the alignment of liquid crystals. Examples of such additives include photopolymerizable monomers such as compounds having polymerizable groups; optically active compounds (for example: S-811 manufactured by Merck & Co., Ltd.); antioxidants; ultraviolet absorbers; pigments; foaming agent; polymerization initiator; or polymerization inhibitor, etc. Examples of positive liquid crystals include ZLI-2293, ZLI-4792, MLC-2003, MLC-2041, MLC-3019, or MLC-7081 manufactured by Merck & Co., Ltd. Negative type liquid crystal, for example, MLC-6608, MLC-6609, MLC-6610, or MLC-7026-100 manufactured by Merck & Co., Ltd. Moreover, as a liquid crystal containing the compound which has a polymeric group, MLC-3023 by Merck & Co. is mentioned.

In addition, if necessary, a liquid crystal display element can be obtained by attaching a polarizing plate to the outer surface of the liquid crystal cell. The polarizing plate attached to the outer surface of the liquid crystal cell can be exemplified: a polarizing film made of a polarizing film called "H film" obtained by sandwiching a cellulose acetate protective film while stretching and aligning polyvinyl alcohol while absorbing iodine. Polarizing plate composed of plate or H film itself.

The IPS substrate, which is a comb-teeth electrode substrate used in the IPS method (mode), has: a base material; a plurality of linear electrodes formed on the base material and arranged in a comb-like shape; Liquid crystal alignment film formed by this method. Also, the FFS substrate, which is a comb electrode substrate used in the FFS method (mode), has: a base material; a surface electrode formed on the base material; an insulating film formed on the surface electrode; A plurality of tooth-shaped linear electrodes; and a liquid crystal alignment film formed on the insulating film to cover the linear electrodes.

Fig. 1 is a schematic cross-sectional view showing an example of a transverse electric field liquid crystal display element of the present invention, which is an example of an IPS mode liquid crystal display element. In the transverse electric field liquid crystal display element 1 illustrated in FIG. 1 , a liquid crystal 3 is sandwiched between a comb-shaped electrode substrate 2 provided with a liquid crystal alignment film 2c and a counter substrate 4 provided with a liquid crystal alignment film 4a. The comb electrode substrate 2 has: a base material 2a; a plurality of linear electrodes 2b formed on the base material 2a and arranged in a comb shape; a liquid crystal alignment film 2c formed on the base material 2a to cover the linear electrodes 2b . The opposite substrate 4 has a base material 4b and a liquid crystal alignment film 4a formed on the base material 4b. The liquid crystal alignment film 2c is, for example, the liquid crystal alignment film of the present invention. The liquid crystal alignment film 4c is also the liquid crystal alignment film of the present invention. In this transverse electric field liquid crystal display element 1 , when a voltage is applied to the linear electrodes 2 b , an electric field is generated between the linear electrodes 2 b as shown by lines of electric force L .

Fig. 2 is a schematic sectional view showing another example of a transverse electric field liquid crystal display element of the present invention, which is an example of an FFS mode liquid crystal display element. In the transverse electric field liquid crystal display element 1 illustrated in FIG. 2 , a liquid crystal 3 is sandwiched between a comb-shaped electrode substrate 2 provided with a liquid crystal alignment film 2 h and an opposing substrate 4 provided with a liquid crystal alignment film 4 a. The comb electrode substrate 2 has: a substrate 2d; a surface electrode 2e formed on the substrate 2d; an insulating film 2f formed on the surface electrode 2e; and a plurality of comb-shaped electrodes formed on the insulating film 2f. a linear electrode 2g; and a liquid crystal alignment film 2h formed on the insulating film 2f to cover the linear electrode 2g. The opposite substrate 4 has: a base material 4b, and a liquid crystal alignment film 4a formed on the base material 4b. The liquid crystal alignment film 2h is, for example, the liquid crystal alignment film of the present invention. The liquid crystal alignment film 4a is also the liquid crystal alignment film of the present invention. In this transverse electric field liquid crystal display element 1, when a voltage is applied to the surface electrode 2e and the line electrode 2g, an electric field is generated between the surface electrode 2e and the line electrode 2g as indicated by lines of force L. [Example]

The following examples are given to describe the present invention in more detail, but the present invention is not limited thereto. The abbreviations of the compounds used and the measurement methods of the respective physical properties are as follows. Also, "Boc" represents tertiary butoxycarbonyl.

(Specific diamines) WA-1 to WA-2: Each is a compound represented by the following formula (WA-1) to (WA-2) [Chemical 32]

式A4、A5表示之化合物係依WO2020/080477號公報記載之合成法合成。 (Other diamines) A1 to A8: Each is a compound represented by the following formula (A1) to (A8) [Chemical 33]

The compounds represented by formulas A4 and A5 were synthesized according to the synthesis method described in WO2020/080477.

(Tetracarboxylic dianhydride) B1~B2: Each is a compound represented by the following formula (B1)~(B2) [Chemical 34]

(Additives) AD-1~AD-2: Each is a compound represented by the following formula (AD-1)~(AD-2) [Chemical 35]

(solvent) NMP: N-methyl-2-pyrrolidone BCS: Ethylene glycol monobutyl ether DMF: Dimethylformamide DMAc: Dimethylacetamide THF: Tetrahydrofuran

(Determination of viscosity) The viscosity of the solution was measured using an E-type viscometer TVE-22H (manufactured by Toki Sangyo Co., Ltd.), with a sample volume of 1.1 mL, and a conical rotor TE-1 (1°34’, R24), at a temperature of 25°C.

(Determination of Molecular Weight) The molecular weight of polyamic acid was obtained by using a normal temperature gel permeation chromatography (GPC) device (GPC-101) (manufactured by Showa Denko Co., Ltd.), a column (KD-803, KD-805 in series) ( Showa Denko Co., Ltd.) was measured in the following manner. Column temperature: 50°C Eluent: N,N-dimethylformamide (additive is lithium bromide monohydrate (LiBr·H ₂ O) 30mmol/L (liter), phosphoric acid anhydrous crystal (orthophosphoric acid) 30mmol/ L, Tetrahydrofuran (THF) 10mL/L) Flow rate: 1.0ml/min Standard sample for assay line production: TSK standard polyethylene oxide (molecular weight; about 900,000, 150,000, 100,000, and 30,000) (manufactured by Tosoh Corporation) and Polyethylene glycol (molecular weight; about 12,000, 4,000, and 1,000) (manufactured by Polymer Laboratory Corporation).

＜Synthesis of specific diamines (WA-1)~(WA-2)＞ The synthesis methods of the specific diamines (WA-1)~(WA-2) are described in detail below. Moreover, diamine (WA-2) is a novel compound which is not disclosed in literature etc.

(Measurement of ¹ H-NMR) Apparatus: Fourier transform type superconducting nuclear magnetic resonance apparatus (FT-NMR) "AVANCE III" (manufactured by BRUKER) 500 MHz. Solvent: deuterated dimethylsulfoxide (DMSO-d ₆ , standard substance: tetramethylsilane),

於1L4口燒瓶中使6-溴-2-萘酚(31.1g、140mmol)、碳酸鉀(38.7g、280mmol)、及碘化鉀(1.16g、7mmol)溶解於DMF(249g)，升溫到100℃並攪拌。於其中緩慢添加1,4-二氯丁烷(8.8g、70mmol)溶於DMF(63g)之溶液，攪拌15小時。以HPLC確認反應結束後，冷卻到室溫，加入純水(620g)，攪拌1小時。分濾析出之結晶，將獲得之固體以甲醇洗淨後，進行減壓乾燥，獲得WA-1-1(產量28.7g、57.4mmol、產率82%、白色固體)。 ¹H-NMR(500MHz，DMSO-d ₆)；δ(ppm)＝8.10(2H,s)、7.83-7.75(4H,m)、7.56-7.54(2H,m)、7.38(2H,s)、7.23-7.22(2H,m)、4.19(4H,t)、1.99-1.95(4H,m) (Monomer Synthesis Example 1: Synthesis of (WA-1)) Diamine (WA-1) was synthesized according to the following route. [chem 36]

Dissolve 6-bromo-2-naphthol (31.1g, 140mmol), potassium carbonate (38.7g, 280mmol), and potassium iodide (1.16g, 7mmol) in DMF (249g) in a 1L 4-neck flask, heat up to 100°C and Stir. A solution in which 1,4-dichlorobutane (8.8 g, 70 mmol) was dissolved in DMF (63 g) was slowly added thereto, and stirred for 15 hours. After confirming completion of reaction by HPLC, it cooled to room temperature, added pure water (620g), and stirred for 1 hour. The precipitated crystals were separated by filtration, the obtained solid was washed with methanol, and then dried under reduced pressure to obtain WA-1-1 (yield: 28.7 g, 57.4 mmol, 82% yield, white solid). ¹ H-NMR (500MHz, DMSO-d ₆ ); 7.23-7.22(2H,m), 4.19(4H,t), 1.99-1.95(4H,m)

In a 1L 4-neck flask, add WA-1-1 (20.0g, 40mmol), diphenylketimine (15.9g, 88mmol), ginseng (dibenzylideneacetone) dipalladium (Pd ₂ (dba) ₃ ) (0.7g, 0.8mmol), 2-dicyclohexylphosphino-2',4',6'-triisopropyl-1,1'-biphenyl (XPhos) (1.52g, 3.2mmol), the third Sodium butoxide (10.8 g, 112 mmol) and THF (400 g) were heated up to 70° C. and stirred for 1 hour. After concentrating the reaction liquid to 200 g, pure water (200 g) was added, and it stirred for 1 hour. The precipitated crystals were recovered by filtration under reduced pressure, transferred to a 4-neck flask, dissolved in DMAc (256 g), and trifluoroacetic acid (12.5 g, 110 mmol) was added slowly, and the temperature was raised to 50°C. After stirring for 30 minutes, the solution was returned to room temperature, and N,N,N',N'-tetramethylethylenediamine (TMEDA) (16.9 g, 146 mmol) was added for neutralization. After the reaction solution was concentrated to 128 g, methanol (256 g) was added and stirred for 1 hour. The precipitated crystals were separated by filtration, and the obtained solid was washed with methanol, and then dried under reduced pressure to obtain WA-1 (13.0 g, 34.9 mmol, 88% yield, light brown solid). This solid was confirmed to be diamine (WA-1) from the result of ¹ H-NMR shown below. ¹ H-NMR (500MHz, DMSO-d ₆ ); ), 6.90-6.88(2H,m), 6.79(2H,d), 5.08-5.06(4H,m), 4.08(4H,t), 1.96-1.92(4H,m)

(Monomer Synthesis Example 2: Synthesis of (WA-2)) Diamine (WA-2) was synthesized according to the following route. [chem 37]

In a 300 mL 4-neck flask, 1,4-dichlorobutane (63.5 g, 500 mmol) was dissolved in DMF (86 g), potassium carbonate (13.8 g, 100 mmol) was added, and the temperature was raised to 100° C. and stirred. A solution of 4-bromo-4'-hydroxybiphenyl (12.4 g, 50 mmol) dissolved in DMF (38 g) was added thereto, followed by stirring for 2 hours. After confirming the completion of the reaction by HPLC, it was cooled to room temperature, and the precipitated salt was removed. The solution was concentrated until it became 64 g, methanol (180 g) and pure water (180 g) were added, and it stirred for 1 hour. The precipitated crystals were separated by filtration, and the obtained solid was washed with methanol, and then dried under reduced pressure to obtain WA-2-1 (yield: 14.6 g, 43.0 mmol, 86% yield, white solid). ¹ H-NMR (500MHz, DMSO-d ₆ ); 1.87(4H,m)

Add WA-2-1 (13.6g, 40mmol), 6-bromo-2-naphthol (8.9g, 40mmol), potassium carbonate (13.8g, 100mmol) and DMF (135g) in a 500mL 4-necked flask, and heat up to 100 °C and stirred for 18 hours. After confirming the completion of the reaction by HPLC, the solution was returned to room temperature, pure water (202 g) was added, and the mixture was stirred for 1 hour. The precipitated crystals were separated by filtration, and the obtained solid was washed with acetonitrile, and then dried under reduced pressure to obtain WA-2-2 (19.5 g, 37.1 mmol, 93% yield, white solid). ¹ H-NMR (500MHz, DMSO-d ₆ ); 7.23(1H,m), 7.04-7.03(2H,m), 4.17-4.11(4H,m), 1.04-1.03(4H,m)

WA-2-2 (19.4g, 37mmol), diphenylketimine (14.7g, 81mmol), ginseng (dibenzylideneacetone) dipalladium (Pd ₂ (dba) ₃ ) ( 0.6g, 0.7mmol), 2-dicyclohexylphosphino-2',4',6'-triisopropyl-1,1'-biphenyl (XPhos) (1.41g, 2.9mmol), tert-butyl Sodium alkoxide (9.9 g, 103 mmol) and THF (389 g) were heated up to 70° C. and stirred for 1 hour. After concentrating the reaction liquid to 190 g, pure water (200 g) was added, and it stirred for 1 hour. The precipitated crystals were recovered by filtration under reduced pressure, transferred to a 4-neck flask, dissolved in THF (537 g), trifluoroacetic acid (12.6 g, 111 mmol) was added slowly, and the temperature was raised to 50°C. After stirring for 30 minutes, the solution was returned to room temperature, and N,N,N',N'-tetramethylethylenediamine (TMEDA) (17.2 g, 148 mmol) was added for neutralization. After concentrating the reaction solution until it became 260 g, methanol (260 g) was added, and it stirred for 1 hour. The precipitated crystals were separated by filtration, and the obtained solid was washed with methanol, and then dried under reduced pressure to obtain WA-2 (13.3 g, 33.4 mmol, 90% yield, light brown solid). From the result of ¹ H-NMR shown below, it was confirmed that this solid was diamine (WA-2). ¹ H-NMR (500MHz, DMSO-d ₆ ); ), 6.79(1H,d), 6.622-6.60(2H,m), 5.11-5.10(4H,m), 4.07-4.05(4H,m), 1.98-1.90(4H,m)

＜Synthesis of Polymer＞ (Synthesis Example 1) Add A1 (0.973g, 9.00mmol), A2 (2.20g, 9.00mmol), WA-1 (2.23g, 6.00mmol), A7 (2.39g, 6.00mmol), B1 (6.39g, 28.5mmol) and NMP (104g), stirred at 40°C for 20 hours to obtain a solution of polyamic acid (A-1) with a solid content concentration of 12% by mass (viscosity: 379mPa·s ). The number average molecular weight (Mn) of this polyamide acid was 13,242, and the weight average molecular weight (Mw) was 34,231.

(Synthesis Example 2) Add A1 (0.973g, 9.00mmol), A2 (2.20g, 9.00mmol), WA-2 (2.39g, 6.00mmol), A7 (2.39g, 6.00mmol), B1 (6.42g, 28.7mmol) and NMP (105g), stirred at 40°C for 20 hours to obtain a solution of polyamic acid (A-2) with a solid content concentration of 12% by mass (viscosity: 398mPa·s ). The Mn of this polyamide acid is 12,019, and the Mw is 33,291.

(Synthesis Example 3) A1 (0.649g, 6.00mmol), A8 (4.78g, 24.0mmol), B2 (5.59g, 28.5mmol) and NMP (99.2g) were added to a 100mL four-necked flask with a stirring device and a nitrogen inlet tube, and Stir at room temperature for 5 hours to obtain a solution of polyamic acid (B-1) with a solid content concentration of 10% by mass (viscosity: 338 mPa·s). The Mn of this polyamide acid was 15,932, and the Mw was 39,013.

(Synthesis example 4 (comparison)) Add A1 (0.973g, 9.00mmol), A2 (2.20g, 9.00mmol), A3 (1.92g, 6.00mmol), A7 (2.39g, 6.00mmol) into a 100mL four-necked flask with a stirring device and a nitrogen inlet tube ), B1 (6.42g, 28.7mmol) and NMP (101g), stirred at 40°C for 20 hours to obtain a solution of polyamic acid (RA-1) with a solid content concentration of 12% by mass (viscosity: 382mPa·s). The Mn of this polyamide acid is 11,912, and the Mw is 33,413.

(Synthesis example 5 (comparison)) Add A1 (0.973g, 9.00mmol), A2 (2.20g, 9.00mmol), A4 (2.07g, 6.00mmol), A7 (2.39g, 6.00mmol) into a 100mL four-necked flask with a stirring device and a nitrogen inlet tube ), B1 (6.38g, 28.4mmol) and NMP (102g), stirred at 40°C for 20 hours to obtain a solution of polyamic acid (RA-2) with a solid content concentration of 12% by mass (viscosity: 411mPa·s). The Mn of this polyamide acid was 12,018, and the Mw was 37,021.

(Synthesis example 6 (comparison)) Add A1 (0.973g, 9.00mmol), A2 (2.20g, 9.00mmol), A5 (2.22g, 6.00mmol), A7 (2.39g, 6.00mmol) into a 100mL four-neck flask with a stirring device and a nitrogen inlet tube ), B1 (6.38g, 28.4mmol) and NMP (103g), stirred at 40°C for 20 hours to obtain a solution of polyamic acid (RA-3) with a solid content concentration of 12% by mass (viscosity: 404mPa·s). The Mn of this polyamide acid is 10,383, and the Mw is 36,113.

(Synthesis example 7 (comparison)) Add A1 (0.973g, 9.00mmol), A2 (2.20g, 9.00mmol), A6 (2.15g, 6.00mmol), A7 (2.39g, 6.00mmol) into a 100mL four-neck flask with a stirring device and a nitrogen inlet tube ), B1 (6.46g, 28.8mmol) and NMP (103g), stirred at 40°C for 20 hours to obtain a solution of polyamic acid (RA-4) with a solid content concentration of 12% by mass (viscosity: 401mPa·s). The Mn of this polyamide acid was 10,099, and the Mw was 36,030.

The types and amounts of diamine components and tetracarboxylic acid components used in Synthesis Examples 1-7 are summarized in Table 1. In the table, the numerical values in parentheses represent the usage-amount (mole part) of a monomer with respect to the total 100 mole parts in each component.

[Table 1] Synthesis example Polyamide Tetracarboxylic acid component Diamine component specific diamine Other diamines 1 A-1 B1(100) WA-1(20) A1(30)A2(30)A7(20) 2 A-2 B1(100) WA-2(20) A1(30)A2(30)A7(20) 3 B-1 B2(100) - A1(20)A8(80) 4 RA-1 B1(100) - A1(30)A2(30)A3(20)A7(20) 5 RA-2 B1(100) - A1(30)A2(30)A4(20)A7(20) 6 RA-3 B1(100) - A1(30)A2(30)A5(20)A7(20) 7 RA-4 B1(100) - A1(30)A2(30)A6(20)A7(20)

＜Preparation of liquid crystal alignment agent＞ (Example 1) Add NMP (9.33g) and BCS (4.00g) to the polyamic acid (A-1) solution (6.67g) obtained in Synthesis Example 1, and stir at room temperature for 2 hours to obtain a liquid crystal alignment agent (V-1) .

(Example 2) In the polyamic acid (A-1) solution (5.30g) obtained in Synthesis Example 1, add the polyamic acid (B-1) solution (9.54g) obtained in Synthesis Example 3, NMP (3.78g), BCS (9.00g), the NMP 10 mass % diluted solution (0.800 g) of AD-1 and the NMP 1 mass % diluted solution (1.59 g) of AD-2 were stirred at room temperature for 2 hours to obtain the liquid crystal alignment agent (V-2 ).

(Example 3) A liquid crystal alignment agent (V-3) was obtained in the same manner as in Example 2 except that the solution of the polyamic acid used was changed from the (A-1) solution to the (A-2) solution.

(Comparative Example 1)~(Comparative Example 4) The polyamic acid solution used was changed from (A-1) solution to (RA-1)~(RA-4) solution, except that the same operation as Example 1 was performed to obtain liquid crystal alignment agent (RV-1) ~(RV-4).

(Comparative Example 5)~(Comparative Example 6) The polyamic acid solution used was changed from (A-1) solution to (RA-2) ~ (RA-3) solution, except that the same operation as in Example 2 was performed to obtain a liquid crystal alignment agent (RV-5) ~(RV-6).

The specifications of the liquid crystal alignment agents obtained in the above-mentioned Examples 1-3 and Comparative Examples 1-6 are shown in Table 2. The numerical value in parentheses of a polymer component represents the ratio (mass part) of each polymer component with respect to the total 100 mass parts of polymer components.

[Table 2] Liquid crystal alignment agent polymer composition Additives 1st ingredient 2nd component Example 1 V-1 A-1(100) - - Example 2 V-2 A-1(40) B-1(60) AD-1, AD-2 Example 3 V-3 A-2(40) B-1(60) AD-1,AD-2 Comparative example 1 RV-1 RA-1(100) - - Comparative example 2 RV-2 RA-2(100) - - Comparative example 3 RV-3 RA-3(100) - - Comparative example 4 RV-4 RA-4(100) - - Comparative Example 5 RV-5 RA-2(40) B-1(60) AD-1, AD-2 Comparative Example 6 RV-6 RA-3(40) B-1(60) AD-1, AD-2

Using the liquid crystal alignment agent obtained above, an FFS-driven liquid crystal cell was produced according to the procedure shown below, and various evaluations were performed.

＜The structure of FFS driving liquid crystal cell＞ Fabricate liquid crystal cells with the configuration of FFS mode liquid crystal display elements. First, the substrate with electrodes is prepared. As the substrate, a rectangular glass substrate of 30 mm×50 mm and a thickness of 0.7 mm was used. An ITO electrode having a solid pattern constituting a counter electrode of the first layer is formed on the substrate. On the counter electrode of the first layer, a SiN (silicon nitride) film formed by CVD (Chemical Vapor Deposition) is formed as the second layer. The SiN film of the second layer has a film thickness of 500nm and functions as an interlayer insulating film. On the SiN film of the second layer, a comb-shaped pixel electrode formed by patterning the ITO film as the third layer is arranged to form two pixels of the first pixel and the second pixel. The size of each pixel is 10mm in length and 5mm in width. At this time, the counter electrode of the first layer and the pixel electrode of the third layer are electrically insulated by the SiN film of the second layer. The pixel electrode of the third layer has the shape of a comb with multiple electrode elements with a width of 3 μm bent at an inner angle of 160° and arranged in parallel at intervals of 6 μm. One pixel connects multiple electrode elements. The zigzag line is the junction, which has the 1st area and the 2nd area. Then filter the liquid crystal alignment agents (V-1)~(V-3), (RV-1)~(RV-6) obtained in the above-mentioned Examples 1~3 and Comparative Examples 1~6 with a filter with a pore size of 1.0 μm A glass substrate having columnar spacers with a height of 4 μm (second glass substrate) on which an ITO film was formed on the back was coated by spin coating on the prepared substrate with electrodes (first glass substrate). After drying on a hot plate at 80°C for 2 minutes, it was calcined in a hot air circulation oven at 230°C for 30 minutes to form a coating film with a thickness of 100nm. The coating surface was irradiated with linearly polarized ultraviolet rays with a wavelength of 254nm at an extinction ratio of 26:1 through a polarizing plate according to the irradiation dose components shown in Table 3 for alignment treatment to obtain a substrate with a liquid crystal alignment film. In addition, the liquid crystal alignment film formed on the above-mentioned substrate with electrodes is aligned so that the direction that divides the inner corner of the pixel bending part into equal parts is perpendicular to the alignment direction of the liquid crystal, and the liquid crystal alignment film formed on the second glass substrate Alignment treatment is carried out so that the alignment direction of the liquid crystal on the first glass substrate is consistent with the alignment direction of the liquid crystal on the second glass substrate when making the liquid crystal cell. Using the above two substrates as a set, a sealant (XN-1500T manufactured by Mitsui Chemicals Co., Ltd.) was printed on the substrate, and the other substrate was bonded so that the alignment direction in which the liquid crystal alignment film surfaces faced each other became 0°. Then heat treatment at 150°C for 60 minutes to harden the sealant and form hollow cells. Liquid crystal MLC-3019 (manufactured by Merck & Co.) was injected into this ghost cell by a depressurized injection method, and the injection port was sealed to obtain an FFS-driven liquid crystal cell. Afterwards, the obtained liquid crystal cells were heated at 120° C. for 1 hour, and left overnight for evaluation.

＜Evaluation of in-plane uniformity of contrast＞ The evaluation of the variation of the torsion angle of the liquid crystal cell was performed using AxoStep manufactured by AXOMETRICS. Set the above-made liquid crystal cell on the measurement stand, and measure the distribution of circular retardation (Circular Retardance) in the pixel plane in the state of no voltage applied, and calculate 3 times the standard deviation σ, which is 3σ. Regarding the in-plane uniformity, the smaller the value of this 3σ, the better. The evaluation criteria were evaluated as "excellent" when less than 1.00, "good" when 1.00 or more and 1.10 or less, and "bad" when greater than 1.10. Table 3 shows the results of evaluating liquid crystal display elements using the respective liquid crystal alignment agents of the above-mentioned examples and comparative examples.

＜Evaluation of the stability of liquid crystal alignment＞ This evaluation is to evaluate the afterimage (also called AC afterimage) caused by the decrease of the alignment performance of the liquid crystal alignment film during long-term AC driving. For the FFS-driven liquid crystal cell produced above, an AC voltage with a frequency of 60 Hz and ±4 V was applied for 120 hours in a constant temperature environment of 60°C. Thereafter, the pixel electrode and the counter electrode of the liquid crystal cell were short-circuited, and left at room temperature for one day in this state. For the liquid crystal cell that has been subjected to the above treatment, the deviation between the alignment direction of the liquid crystal in the first region of the pixel and the alignment direction of the liquid crystal in the second region of the pixel in the state where no voltage is applied is calculated in terms of angle. Specifically, a liquid crystal cell is arranged between two polarizers whose polarization axes are perpendicular to each other, the backlight is turned on, and the arrangement angle of the liquid crystal cell is adjusted so that the intensity of the transmitted light in the first area of the pixel becomes the minimum. Then, find The angle of rotation required to rotate the liquid crystal cell so that the transmitted light intensity of the second region of the pixel becomes the minimum is shown. The stability of liquid crystal alignment means that the smaller the value of the rotation angle is, the better it is. In terms of evaluation criteria, when it is less than 0.05 degrees, it is rated as "excellent", when it is more than 0.05 degrees and less than 0.10 degrees, it is rated as "good", and when it is greater than 0.10 degrees, it is rated as "bad".

Table 3 shows the evaluation results of the liquid crystal display elements using the liquid crystal alignment agents of the above-mentioned examples and comparative examples.

[table 3]

As shown in Table 3, the liquid crystal alignment films obtained from the liquid crystal alignment agents using specific diamines WA-1~WA-2, compared with the liquid crystal alignment films obtained from liquid crystal alignment agents composed of diamine components that do not contain specific diamines Alignment film can obtain high in-plane uniformity with less light exposure. Furthermore, it shows the same or higher liquid crystal alignment stability than conventional liquid crystal alignment films.

The liquid crystal alignment film obtained from the liquid crystal alignment agent of the present invention can be applied to liquid crystal display elements. And these devices are also useful in liquid crystal displays for display purposes, and in dimming windows and shutters that control the transmission and blocking of light. [Industrial Utilization]

By using the liquid crystal alignment agent of the present invention, the variation (inhomogeneity) of the twist angle of the liquid crystal in the liquid crystal alignment film plane is small, and the range of the light irradiation amount used to obtain the liquid crystal alignment film is expanded, and the quality can be obtained with good efficiency Good liquid crystal alignment film. Therefore, it can be expected to be used in liquid crystal display elements requiring high display quality. And these devices are also useful in liquid crystal displays for display purposes, and further in dimming windows and shutters for controlling light transmission and blocking.

1: Transverse electric field liquid crystal display element 2: Comb electrode substrate 2a: Substrate 2b: Wire electrode 2c: Liquid crystal alignment film 2d: Substrate 2e: surface electrode 2f: insulating film 2g: wire electrode 2h: Liquid crystal alignment film 3: LCD 4: Facing the substrate 4a: Liquid crystal alignment film 4b: Substrate L: power line

Fig. 1 shows a schematic cross-sectional view of an example of a transverse electric field liquid crystal display element of the present invention. Fig. 2 shows a schematic cross-sectional view of another example of the transverse electric field liquid crystal display element of the present invention.

1: Transverse electric field liquid crystal display element

2: Comb electrode substrate

2a: Substrate

2b: Wire electrode

2c: Liquid crystal alignment film

3: LCD

4: Facing the substrate

4a: Liquid crystal alignment film

4b: Substrate

L: power line

Claims (17)

A liquid crystal alignment agent, characterized by containing a polymer (A), the polymer (A) is selected from a polyimide precursor having a repeating unit (a1) represented by the following formula (1) and the polyimide At least one of the group consisting of polyimides of imides of amine precursors,

In formula (1), X ₁ represents a tetravalent organic group, Y ₁ is a divalent organic group represented by the following formula (H) and has 3 or more benzene rings, R and Z each independently represent a hydrogen atom or a monovalent organic group. base,

In formula (H), L ₁ and L _1' each independently represent a single bond, -O-, -S-, -C(=O)-, -OC(=O)-, or -C(=O )-NR-(R represents a hydrogen atom or a monovalent organic group), A represents an alkylene group with 4 to 10 carbons, Ar ₁ and Ar _1' each independently represent a benzene ring, a biphenyl structure, or a naphthalene ring, Any hydrogen atom on the ring of Ar ₁ and Ar _1' may also be substituted by a monovalent group; * represents an atomic bond. The liquid crystal alignment agent according to Claim 1, wherein the group "*-L ₁ -AL _1' -*" (* represents an atomic bond) in the formula (H) is the group "*-(CH ₂ ) _n -*" , group "*-O-(CH ₂ ) _n -O-*", group "*-C(=O)-(CH ₂ ) _n -C(=O)-*", group "*-C(= O)-NR-(CH ₂ ) _n -O-*”, group “*-OC(=O)-(CH ₂ ) _n -O-*”, group “*-OC(=O)-(CH ₂ ) _n -OC(=O)-*", group "*-OC(=O)-(CH ₂ ) _n -C(=O)-O-*", group "*-S-(CH ₂ ) _n -S-*", group "*-C(=O)-NR-(CH ₂ ) _n -NR-C(=O)-*", group "*-C(=O)-O-(CH ₂ ) _n -OC(=O)-*", group "*-O-(CH ₂ ) _n -*", group "*-S-(CH ₂ ) _n -*", or group "*-NR-C (=O)-(CH ₂ ) _n -C(=O)-NR-*" represents a group, R represents a hydrogen atom or a monovalent organic group, n is an integer from 4 to 10, and * represents an atomic bond. Such as the liquid crystal alignment agent of claim item 1, wherein Y in the formula ( ₁ ) is a divalent organic group represented by any one of the following formulas (h-1) to (h-4),

In the formulas (h-1)~(h-4), R _a1 ~R _a4 represent monovalent organic groups, and L represents the group "*-L ₁ -AL _1' -*" in the above formula (H) (* represents atomic bond), m each independently is an integer of 0 to 6, n each independently is an integer of 0 to 4, when there are multiple R _a1 to R _a4 , each may be the same or different, and * represents an atomic bond. The liquid crystal alignment agent according to claim 1, wherein the polymer (A) is selected from polyimide precursors having repeating units (a2) represented by the following formula (2) and is the polyimide precursor At least one polymer in the group consisting of polyimides of amides,

In formula (2), X ₂ represents a 4-valent organic group, Y ₂ represents a divalent organic group represented by the following formulas (o-1)~(o-14), R and Z are each the same as R in the above formula (1) , and Z are synonyms,

In formulas (o-1)~(o-14), * represents an atomic bond; in formulas (o-13)~(o-14), the two ms are independent; formulas (o-1)~(o- Any hydrogen atom on the benzene ring, biphenyl structure or naphthalene ring in 14) may be substituted by a monovalent group. The liquid crystal alignment agent according to Claim 1, wherein the polymer (A) is selected from the repeating unit (a2') represented by the following formula (2') and the repeating unit (a3) represented by the following formula (3) ) at least one polyimide precursor in the group consisting of and at least one polymer in the group consisting of polyimide which is an imide of the polyimide precursor,

In formula (2') and formula (3), X _2' and X ₃ represent a 4-valent organic group, Y _2' represents a divalent organic group represented by the following formula (O2), and Y ₃ represents a group in the molecule " -N(D)-(D represents a carbamate-based protecting group)" is a divalent organic group with 6 to 30 carbon atoms, and R, and Z are synonymous with R and Z in the above formula (1),

In the formula (O2), m represents an integer of 0 to 2. When m is 0, Ar _2' represents a benzene ring or a naphthalene ring. When m is 1 to 2, Ar _{2 '} independently represents a benzene ring. Any hydrogen atom on the ring can also be substituted by a monovalent group. Q _2' represents a single bond or -O-, * represents an atomic bond. When there are multiple Ar _2' and Q _2' , each can be the same or can be different. As the liquid crystal alignment agent of claim ₁ , wherein, the X1 is derived from acyclic aliphatic tetracarboxylic dianhydride or derivatives thereof, alicyclic tetracarboxylic dianhydride or derivatives thereof, or aromatic tetracarboxylic acid The 4-valent organic group of dianhydride or its derivatives is derived from tetracarboxylic dicarboxylic acid having at least one substructure selected from the group consisting of cyclobutane ring structure, cyclopentane ring structure and cyclohexane ring structure. A tetravalent organic group of an anhydride or a derivative thereof. The liquid crystal alignment agent according to Claim 1, wherein, in the polymer (A), the total content of the repeating unit (a1) and the imidized structure of the repeating unit (a1) is 5 to 100 mo of all repeating units Ear%. The liquid crystal alignment agent according to Claim 1, wherein, in the polymer (A), the total content of the repeating unit (a1) and the imidized structure of the repeating unit (a1) is 5 mol% of all repeating units Above and below 95 mole%. The liquid crystal alignment agent according to claim 4, wherein, in the polymer (A), the total content of the repeating unit (a1), the repeating unit (a2) and their imidized structures is the total content of all repeating units More than 10 mol%. The liquid crystal alignment agent according to claim 1, which is used in the formation of liquid crystal alignment film for photo-alignment treatment. A liquid crystal alignment film obtained from the liquid crystal alignment agent according to any one of claims 1 to 10. A liquid crystal display element comprising the liquid crystal alignment film according to claim 11. A method for manufacturing a liquid crystal display device, comprising the following steps (1) to (3): Step (1): Coating the liquid crystal alignment agent according to any one of claims 1 to 10 on the substrate Step (2): Calcining the coated liquid crystal alignment agent Step (3): performing alignment treatment on the calcined film obtained in step (2). The method for manufacturing a liquid crystal display element according to claim 13, wherein the alignment treatment is photo-alignment treatment. The method for manufacturing a liquid crystal display device according to claim 14, wherein the radiation dose in the photo-alignment treatment is 100-1,500 mJ/cm ² . The method for manufacturing a liquid crystal display element as claimed in item 13, further comprising the following step (4): Step (4): For the calcined film subjected to alignment treatment in step (3), heat treatment at 50-300°C is performed. A liquid crystal display element obtained by the method for manufacturing a liquid crystal display element according to any one of claims 13 to 16.

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