KR102102211B1 - Liquid crystal aligning agent, liquid crystal alignment film, liquid crystal display device, producing method of the liquid crystal aligning agent, producing method of the liquid crystal alignment film, phase difference film and producing method of the phase difference film - Google Patents

Abstract

(식 (1) 중, R¹∼R⁴는, 각각 독립적으로 직쇄상 또는 분기상의 탄소수 1∼6의 탄화수소기 또는 상기 탄화수소기의 C-C 결합 간에, -O-, -COO- 및 -OCO-로부터 선택되는 적어도 1종을 갖는 기임).(Task) Providing a liquid crystal aligning agent capable of sufficiently dissolving a polymer and forming a liquid crystal aligning film by heating at a relatively low temperature.
(Solution) A solvent comprising at least one polymer (A) selected from the group consisting of polyamic acid, polyimide, polyamic acid ester and polyorganosiloxane, and compound (p1) represented by the following formula (1): Liquid crystal aligning agent containing:

(In the formula (1), R ¹ to R ⁴ are each independently a linear or branched hydrocarbon group having 1 to 6 carbon atoms or a CC bond of the hydrocarbon group, from -O-, -COO- and -OCO- A group having at least one selected).

Description

Liquid crystal aligning agent, liquid crystal aligning film, liquid crystal display element, liquid crystal aligning agent manufacturing method, liquid crystal aligning film manufacturing method, retardation film and retardation film manufacturing method {LIQUID CRYSTAL ALIGNING AGENT, LIQUID CRYSTAL ALIGNMENT FILM, LIQUID CRYSTAL DISPLAY DEVICE, PRODUCING METHOD OF THE LIQUID CRYSTAL ALIGNING AGENT, PRODUCING METHOD OF THE LIQUID CRYSTAL ALIGNMENT FILM, PHASE DIFFERENCE FILM AND PRODUCING METHOD OF THE PHASE DIFFERENCE FILM}

The present invention relates to a method for producing a liquid crystal aligning agent, a liquid crystal aligning film, a liquid crystal display element, a liquid crystal aligning film, and a method for producing a retardation film and a retardation film. Specifically, polyimide, polyamic acid, and the like can be sufficiently dissolved. Moreover, it is related with the liquid crystal aligning agent etc. which can form a liquid crystal aligning film by heating at comparatively low temperature.

The liquid crystal display element is formed by placing a substrate for a liquid crystal display element on which a liquid crystal alignment film is formed on a surface of a substrate on which a transparent conductive film is formed, and encapsulating the liquid crystal molecules in alignment between the pair of substrates. As such a liquid crystal display element, a so-called twisted nematic (TN) type element in which the long axis of liquid crystal molecules is continuously twisted 90 degrees from one substrate to the other is known. In addition, compared to TN type devices, STN (Super Twisted Nematic) type devices that can achieve higher contrast ratios, IPS (In-Plane Switching) type devices with less visual dependence, have less visual dependence, and also have a rubbing treatment during alignment of the liquid crystal. A VA (Vertical Alignment) type device that does not require, an optical compensation band (OCB) type liquid crystal display device having low visual dependency and excellent high-speed response of an image screen has been developed.

The liquid crystal aligning film used in these liquid crystal display elements dissolves polyimide or polyamic acid in a solvent such as 1-methyl-2-pyrrolidone or γ-butyrolactone, as shown in Patent Documents 1 to 3, for example. It is formed by applying the contained liquid crystal aligning agent to a substrate and then heating it. By using polyimide or polyamic acid as a liquid crystal aligning agent, a liquid crystal aligning film excellent in heat resistance, affinity with liquid crystals, and mechanical strength can be obtained.

Japanese Patent Publication No. Hei 9-241646 Japanese Patent Publication No. 2001-305549 Japanese Patent Publication No. Hei 9-278724

Here, when dissolving polyimide or polyamic acid or the like to form a liquid crystal aligning agent, as described above, it is necessary to use 1-methyl-2-pyrrolidone, γ-butyrolactone, or the like. However, when such a solvent is used, it is considered that there may be a problem in forming a liquid crystal aligning film by applying a liquid crystal aligning agent to a substrate.

Specifically, 1-methyl-2-pyrrolidone, γ-butyrolactone, etc. are high boiling point (for example, 200 ° C) solvents, and when such high boiling point solvents are used, when forming a liquid crystal alignment film It is necessary to perform heating at a high temperature.

In addition, formation of a liquid crystal aligning film is performed with respect to the board | substrate with a color filter. For example, in the case of using a radiation-sensitive composition containing a dye as a color filter, since the dye is not highly heat-resistant, if heating at a high temperature during the formation of the liquid crystal alignment film, it is feared that the color filter is adversely affected. do.

In addition, when heating at a high temperature is required, for example, when forming a liquid crystal alignment film, the total amount of heat generated in the manufacturing process increases as much, and thus the amount of carbon dioxide emitted increases.

The main object of the present invention is to provide a liquid crystal aligning agent capable of sufficiently dissolving a polymer such as polyimide or polyamic acid and forming a liquid crystal aligning film by heating at a relatively low temperature.

As a result of earnest examination to achieve the above-described problems of the prior art, the present inventors have found that the above problems can be solved by using a specific compound as at least a part of the solvent, and have come to complete the present invention. Specifically, the following liquid crystal aligning agent is provided by the present invention.

In one aspect of the present invention, at least one polymer (A) selected from the group consisting of polyamic acid, polyimide, polyamic acid ester and polyorganosiloxane, and a compound represented by the following formula (1) (p1) It provides a liquid crystal aligning agent containing a solvent comprising:

(In the formula (1), R ¹ to R ⁴ are each independently a linear or branched hydrocarbon group having 1 to 6 carbon atoms or a CC bond of the hydrocarbon group, from -O-, -COO- and -OCO- A group having at least one selected).

By using compound (p1) as at least a part of the solvent of the liquid crystal aligning agent, polyimide, polyamic acid, and the like can be sufficiently dissolved, and a liquid crystal aligning film can be formed by heating at a relatively low temperature.

(Form for carrying out the invention)

The liquid crystal aligning agent of the present invention contains at least one polymer (A) selected from the group consisting of polyamic acid, polyimide, polyamic acid ester, and polyorganosiloxane as a polymer component, and the polymer (A) ) Is dissolved in a solvent. Hereinafter, the liquid crystal aligning agent will be described.

<Polyamic acid>

The polyamic acid in the present invention can be obtained by reacting tetracarboxylic acid anhydride and diamine.

[Tetracarboxylic acid 2 anhydride]

Examples of the tetracarboxylic acid anhydride used for synthesizing the polyamic acid in the present invention include aliphatic tetracarboxylic acid anhydride, alicyclic tetracarboxylic acid anhydride, aromatic tetracarboxylic acid anhydride, and the like. As these specific examples,

Examples of the aliphatic tetracarboxylic acid anhydride include 1,2,3,4-butanetetracarboxylic acid anhydride and the like;

As an alicyclic tetracarboxylic acid anhydride, for example, 1,2,3,4-cyclobutanetetracarboxylic acid anhydride, 2,3,5-tricarboxylic cyclopentyl acetic anhydride, 1,3,3a, 4, 5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4 , 5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 3- Oxabicyclo [3.2.1] octane-2,4-dione-6-spiro-3 '-(tetrahydrofuran-2', 5'-dione), 5- (2,5-dioxotetrahydro-3 -Furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride, 3,5,6-tricarbox-2-carboxymethylnorbornane 2: 3,5: 6-2 anhydride, 2 , 4,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4,6: 8-2 anhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecan-3, 5,8,10-tetraone, bicyclo [2.2.1] heptane-2,3,5,6-tetracarboxylic acid 2: 3,5: 6-2 anhydride, cyclopentanoic acid anhydride, between Clohexanetetracarboxylic acid anhydride and the like;

As aromatic tetracarboxylic acid anhydride, for example, pyromellitic acid anhydride, etc .; In addition to those listed above, tetracarboxylic acid dianhydride described in JP 2010-97188 A can be used. In addition, the tetracarboxylic acid dianhydride can be used alone or in combination of two or more.

As a tetracarboxylic dianhydride used for synthesis, it is preferable to include an alicyclic tetracarboxylic dianhydride from the viewpoint of transparency and solubility in a solvent. Further, among the alicyclic tetracarboxylic acid anhydrides, 2,3,5-tricarboxyliccyclopentylacetic acid 2 anhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5- Dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro -2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane- 2: 4,6: 8-2 anhydride, bicyclo [2.2.1] heptane-2,3,5,6-tetracarboxylic acid 2: 3,5: 6-2 anhydride, cyclopentanoic acid 2 anhydride, 1, It is preferable to include at least one member selected from the group consisting of 2,4,5-cyclohexanetetracarboxylic acid anhydride and 1,2,3,4-cyclobutanetetracarboxylic acid anhydride, and 2,3,5 -Tricarboxylic cyclopentyl acetic anhydride, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4,6: 8-2 anhydride, bicyclo [2.2.1] heptane-2, 3,5,6-tetracarboxylic acid 2: 3,5: 6-2 nothing Water, cyclopentenyl to include at least one selected from the acid dianhydride and 1,2,3,4-cyclobutane tetracarboxylic acid group consisting of a dianhydride are particularly preferred.

As the tetracarboxylic acid anhydride, 2,3,5-tricarboxycyclopentyl acetic acid 2 anhydride, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4,6: 8-2 When the anhydride and at least one selected from the group consisting of 1,2,3,4-cyclobutanetetracarboxylic acid and anhydride are included, the total content of these compounds is tetracarboxylic acid used for the synthesis of polyamic acid. It is preferable that it is 10 mol% or more with respect to the total amount of 2 anhydrides, and it is more preferable that it is 20-100 mol%.

[Diamine]

Examples of the diamine used to synthesize the polyamic acid in the present invention include aliphatic diamines, alicyclic diamines, aromatic diamines, diamino organosiloxanes, and the like. Specific examples of these diamines include aliphatic diamines such as metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, and hexamethylenediamine;

As the alicyclic diamine, for example, 1,4-diaminocyclohexane, 4,4'-methylenebis (cyclohexylamine), 1,3-bis (aminomethyl) cyclohexane, etc .;

As an aromatic diamine, for example, p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl sulfide, 1,5-diaminonaphthalene, 2,2'-dimethyl -4,4'-diaminobiphenyl, 2,2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl, 2,7-diaminofluorene, 4,4'-diamino Diphenyl ether, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis [4- (4-aminophenoxy) Si) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 4,4 '-(p-phenylenediisopropylidene) bisaniline, 4,4'-(m- Phenylenediisopropylidene) bisaniline, 1,4-bis (4-aminophenoxy) benzene, 4,4'-bis (4-aminophenoxy) biphenyl, 2,6-diaminopyridine, 3,4 -Diaminopyridine, 2,4-diaminopyrimidine, 3,6-diaminoacridine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl-3 , 6-diaminocarbazole, N-phenyl -3,6-diaminocarbazole, N, N'-bis (4-aminophenyl) -benzidine, N, N'-bis (4-aminophenyl) -N, N'-dimethylbenzidine, 1,4- Bis- (4-aminophenyl) -piperazine, 1- (4-aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-inden-5-amine, 1- (4-amino Phenyl) -2,3-dihydro-1,3,3-trimethyl-1H-inden-6-amine, 3,5-diaminobenzoic acid, cholestanyloxy-3,5-diaminobenzene, cholestenyl Oxy-3,5-diaminobenzene, cholestanyloxy-2,4-diaminobenzene, cholestenyloxy-2,4-diaminobenzene, 3,5-diaminobenzoic acid cholestanyl, 3,5 -Diaminobenzoic acid cholesteryl, 3,5-diaminobenzoic acid ranstanyl, 3,6-bis (4-aminobenzoyloxy) cholestane, 3,6-bis (4-aminophenoxy) cholestane, 4 -(4'-trifluoromethoxybenzoyloxy) cyclohexyl-3,5-diaminobenzoate, 4- (4'-trifluoromethylbenzoyloxy) cyclohexyl-3,5-diaminobenzoate, 1 , 1-bis (4-((aminofe Neil) methyl) phenyl) -4-butylcyclohexane, 1,1-bis (4-((aminophenyl) methyl) phenyl) -4-heptylcyclohexane, 1,1-bis (4-((aminophenoxy ) Methyl) phenyl) -4-heptylcyclohexane, 1,1-bis (4-((aminophenyl) methyl) phenyl) -4- (4-heptylcyclohexyl) cyclohexane, 2,4-diamino-N , N-diallyl aniline, 4-aminobenzylamine, 3-aminobenzylamine, compounds represented by 2- (2,4-diaminophenoxy) ethyl methacrylate, and the like;

As the diamino organosiloxane, for example, 1,3-bis (3-aminopropyl) -tetramethyldisiloxane and the like can be mentioned, and the diamine described in JP 2010-97188 A can be used. have. Moreover, these diamine can be used individually by 1 type or in combination of 2 or more type.

As the diamine used for synthesizing the polyamic acid in the present invention, in particular, a compound represented by the following formula (d-1), a compound represented by the following formula (d-2), a compound represented by the following formula (d-3) and It is preferably synthesized using at least one diamine (hereinafter also referred to as "specific diamine") selected from the group consisting of compounds represented by the following formula (d-4):

(In formula (d-1), X ¹ and X ² are each independently a single bond, -O-, -S-, -OCO- or -COO-, Y ¹ is an oxygen atom or a sulfur atom , R ¹ and R ² are each independently an alkanediyl group having 1 to 3 carbon atoms; n1 is 0 or 1, and n2 and n3 are integers satisfying n2 + n3 = 2 when n1 = 0, n1 When = 1, n2 = n3 = 1; In formula (d-2), X ³ is a single bond, -O- or -S-, m1 is an integer from 0 to 3; m2 is m1 = In the case of 0, it is an integer of 1 to 12, and when m1 is an integer of 1 to 3, m2 = 2; in Formula (d-3), R ³ is a linear or branched atom having 1 to 12 carbon atoms. A hydrocarbon group, R ⁴ is a hydrogen atom, or a linear or branched monovalent hydrocarbon group having 1 to 12 carbon atoms, and R ⁵ and R ⁶ are each independently a hydrogen atom or a methyl group; formula (d-4) ) of, X ⁴ and X ⁵ are, each independently, a single bond, an -O-, -COO- or -OCO-, R ⁷ is of 1 to 3 carbons alkanes Weather gt; a is 0 or 1, b is an integer of 0~2, c is an integer of 1~20, k is 0 or 1; however, do not have a and b at the same time is zero).

(Compound represented by formula (d-1))

In the formula (d-1), examples of the alkanediyl group having 1 to 3 carbon atoms in R ¹ and R ² include, for example, a methylene group, an ethylene group, a propane-1,2-diyl group, and propane-1,3- Diyl group, propane-2,3-diyl group, etc. are mentioned. Among these, a methylene group, an ethylene group, or a propane-1,3-diyl group is preferable.

X ¹ and X ² are a single bond, -O-, -S-, -OCO- or -COO-. In addition, X ¹ and X ² may be the same or different. Among them, X ¹ and X ² are preferably a single bond or -O- or -S-.

Y ¹ is an oxygen atom or a sulfur atom. Preferably, it is an oxygen atom.

The two primary amino groups of the compound represented by the formula (d-1) may be bound to the same benzene ring when n1 = 0, or may be bound to two different benzene rings one by one. On the other hand, when n1 = 1, two primary amino groups are each bonded to a different benzene ring.

The bonding position of the primary amino group on the benzene ring is not particularly limited. For example, when there is one primary amino group on the benzene ring, the bonding position may be any of 2-position, 3-position, and 4-position with respect to other groups, and is preferably 3-position or 4-position. It is more preferable that it is a 4-position. In addition, when there are two primary amino groups on the benzene ring, the bonding position is, for example, 2,4-position, 2,5-position, etc. with respect to other groups, and among them, 2,4-position desirable.

Further, the hydrogen atom on the benzene ring to which the primary amino group is bonded may be substituted with a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a monovalent group wherein at least one hydrogen atom on the hydrocarbon group is substituted with a fluorine atom, or a fluorine atom. . Examples of the monovalent hydrocarbon group in this case include an alkyl group having 1 to 10 carbon atoms, an alkenyl group, a cycloalkyl group, an aryl group (such as a phenyl group), and an aralkyl group (such as a benzyl group).

As a preferable specific example of the compound represented by said formula (d-1), as a compound of n1 = 0, 4,4'- diaminodiphenylamine, 2,4-diaminodiphenylamine, etc. are mentioned; As a compound of n1 = 1, for example, 1,3-bis (4-aminobenzyl) urea, 1,3-bis (4-aminophenethyl) urea, 1,3-bis (3-aminobenzyl) urea, 1- (4-aminobenzyl) -3- (4-aminophenethyl) urea, 1,3-bis (2- (4-aminophenoxy) ethyl) urea, 1,3-bis (3- (4- Aminophenoxy) propyl) urea, 1,3-bis (4-aminobenzyl) thiourea, 1,3-bis (2-aminobenzyl) urea, 1,3-bis (2-aminophenethyl) urea, 1 , 3-bis (2- (2-aminobenzoyloxy) ethyl) urea, 1,3-bis (3- (2-aminobenzoyloxy) propyl) urea, and the like; Each can be lifted. Moreover, as a compound represented by said formula (d-1), these compounds can be used individually by 1 type or in combination of 2 or more type.

(Compound represented by formula (d-2))

In the formula (d-2), X ³ is a single bond, -O- or -S-, preferably a single bond or -O-.

When m1 = 0, m2 is an integer of 1-12. In this case, from the viewpoint of improving the heat resistance of the resulting polymer, m2 is preferably 1 to 10, and more preferably 1 to 8. In addition, m1 = 0 is preferable from the viewpoint of satisfactory rubbing resistance while preserving good liquid crystal alignment, and m1 is preferably an integer of 1 to 3 from the viewpoint of reducing the pretilt angle of the liquid crystal molecules.

The bonding position of the primary amino group on the benzene ring is not particularly limited, but it is preferable that each primary amino group is a 3-position or 4-position with respect to other groups, and the 4-position is more preferable. Further, the hydrogen atom on the benzene ring to which the primary amino group is bonded may be substituted with a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a monovalent group wherein at least one hydrogen atom on the hydrocarbon group is substituted with a fluorine atom, or a fluorine atom. .

Preferred specific examples of the compound represented by the formula (d-2) include, for example, bis (4-aminophenoxy) methane, bis (4-aminophenoxy) ethane, bis (4-aminophenoxy) propane, bis ( 4-aminophenoxy) butane, bis (4-aminophenoxy) pentane, bis (4-aminophenoxy) hexane, bis (4-aminophenoxy) heptane, bis (4-aminophenoxy) octane, bis ( 4-aminophenoxy) nonane, bis (4-aminophenoxy) decane, bis (4-aminophenyl) methane, bis (4-aminophenyl) ethane, bis (4-aminophenyl) propane, bis (4-amino Phenyl) butane, bis (4-aminophenyl) pentane, bis (4-aminophenyl) hexane, bis (4-aminophenyl) heptane, bis (4-aminophenyl) octane, bis (4-aminophenyl) nonane, bis (4-aminophenyl) decane, 1,3-bis (4-aminophenylsulfanyl) propane, 1,4-bis (4-aminophenylsulfanyl) butane, and the like. Moreover, as a compound represented by said formula (d-2), these exemplary compounds can be used individually by 1 type or in mixture of 2 or more types.

(Compound represented by formula (d-3))

In the formula (d-3), R ³ is a linear or branched monovalent hydrocarbon group having 1 to 12 carbon atoms. Examples of the specific examples include alkyl groups such as methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, t-butyl group, pentyl group, hexyl group, octyl group and decyl group; Alkenyl groups such as vinyl groups and allyl groups; Cycloalkyl groups such as cyclopentyl group and cyclohexyl group; Aryl groups such as phenyl groups and tolyl groups; And aralkyl groups such as benzyl groups. The number of carbon atoms in R ³ is preferably 1 to 6, and more preferably 1 to 3. Moreover, as R <^3> , it is preferable that it is a chain hydrocarbon group, it is preferable that it is a chain hydrocarbon group containing a carbon-carbon double bond, and it is more preferable that it is an alkenyl group, such as an allyl group.

R ⁴ is a hydrogen atom or a linear or branched monovalent hydrocarbon group having 1 to 12 carbon atoms. Examples of the hydrocarbon group include a chain hydrocarbon group having 1 to 12 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, and an aromatic hydrocarbon group having 5 to 12 carbon atoms, and specific examples thereof include groups exemplified in the description of R ³ above. You can. As R ⁴ , it is preferably a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms, more preferably a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms, and more preferably a hydrogen atom or a methyl group.

R ⁵ and R ⁶ are each independently a hydrogen atom or a methyl group, and it is preferable that they are all hydrogen atoms.

In the diaminophenyl group of the formula (d-3), the bonding position of the two primary amino groups is not particularly limited, but is 2,4-position or 2,5-position with respect to the N-allyl structure bonded to the benzene ring. It is preferable, and it is more preferable that it is a 2,4-position. Further, the hydrogen atom on the benzene ring to which the primary amino group is bonded may be substituted with a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a monovalent group wherein at least one hydrogen atom on the hydrocarbon group is substituted with a fluorine atom, or a fluorine atom. .

Preferable specific examples of the compound represented by the formula (d-3) include, for example, 2,4-diamino-N, N-diallyaniline, 2,5-diamino-N, N-diallyaniline, and the following formula. and compounds represented by each of (d-3-1) to (d-3-3). Among these, 2,4-diamino-N, N-diallyaniline or 2,5-diamino-N, N-diallyaniline can be preferably used.

(Compound represented by formula (d-4))

In the formula (d-4), as the divalent group represented by "-X ^4- (R ⁷ -X ⁵ ) _k- ", an alkanediyl group having 1 to 3 carbon atoms, * -O-, * -COO-, or It is preferable that * -OC ₂ H ₄ -O- (however, a bonding hand with "*" is bonded to a diaminophenyl group).

The group "-C _c H _{2c +1} " is preferably linear, and specific examples thereof include methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, and n -Heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-dodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n- Heptadecyl group, n-octadecyl group, n-nonadecyl group, n-eicosyl group etc. are mentioned.

The two primary amino groups in the diaminophenyl group are preferably in the 2,4-position or 3,5-position relative to the group "X ⁴ ", and more preferably in the 2,4-position. Further, the hydrogen atom on the benzene ring to which the primary amino group is bonded may be substituted with a fluorine atom, a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a group in which at least one hydrogen atom on the hydrocarbon group is substituted with a fluorine atom.

As a preferable specific example of the compound represented by said formula (d-4), the compound etc. which are represented by each of following formula (d-4-1)-(d-4-11) are mentioned, for example.

In the synthesis of the polyamic acid of the present invention, a specific diamine can be appropriately selected and used from the above compounds depending on the driving mode of the liquid crystal display device to be produced. Specifically, a liquid crystal aligning agent suitable for a FFS (Fringe Field Switching) type liquid crystal display device can be produced by using the compound represented by the formula (d-1) as the specific diamine. Further, by using at least one member selected from the group consisting of the compound represented by the formula (d-2) and the compound represented by the formula (d-3), a liquid crystal suitable for a TN (Twisted Nematic) type liquid crystal display device An alignment agent can be produced, and by using the compound represented by the formula (d-4), a liquid crystal alignment agent suitable for a vertical alignment type liquid crystal display element can be produced.

[Molecular weight regulator]

In synthesizing the polyamic acid, the terminal-modified polymer may be synthesized by using an appropriate molecular weight modifier together with the above tetracarboxylic acid anhydride and diamine. By using such a terminal-modified polymer, the coating property (printability) of the liquid crystal aligning agent can be further improved without impairing the effect of the present invention.

Examples of the molecular weight regulator include an acid anhydride, a monoamine compound, and a monoisocyanate compound. As these specific examples, as the acid anhydride, for example, maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, n-tetradecylsuccinic anhydride, n-hexadecylsuccinic anhydride, etc. of; Examples of the monoamine compound include aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, and the like; As a monoisocyanate compound, phenyl isocyanate, naphthyl isocyanate, etc. are mentioned, for example, respectively.

The proportion of the molecular weight modifier used is preferably 20 parts by weight or less, and more preferably 10 parts by weight or less, based on 100 parts by weight of the total of tetracarboxylic anhydride and diamine used.

<Synthesis of polyamic acid>

The ratio of the tetracarboxylic acid anhydride and the diamine used in the synthesis reaction of the polyamic acid in the present invention is 0.2 to 2 equivalents of the acid anhydride group of the tetracarboxylic acid anhydride relative to the amino group equivalent of the diamine. It is preferable, and the ratio which becomes 0.3 to 1.2 equivalent is more preferable.

The synthetic reaction of the polyamic acid is preferably carried out in an organic solvent. The reaction temperature at this time is preferably -20 ° C to 150 ° C, and more preferably 0 to 100 ° C. Further, the reaction time is preferably 0.1 to 24 hours, and more preferably 0.5 to 12 hours.

Here, examples of the organic solvent include non-protonic polar solvents, phenolic solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, hydrocarbons, and the like.

As specific examples of these organic solvents, as the aprotic polar solvent, for example, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N-ethyl-2-pyrrolid Money, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, tetramethylurea, hexamethylphosphotriamide, compounds represented by the following formula (1); As said phenolic solvent, For example, phenol, m-cresol, xylenol, halogenated phenol, etc .; Examples of the alcohol include methyl alcohol, ethyl alcohol, isopropyl alcohol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol, triethylene glycol, ethylene glycol monomethyl ether, and the like;

As the ketone, for example, acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, etc .; As the ester, for example, ethyl lactate, butyl lactate, methyl acetate, ethyl acetate, butyl acetate, methylmethoxypropionate, ethylethoxypropionate, diethyl oxalate, diethyl malonate, isoamylpropionate Nate, isoamyl isobutyrate, etc .; As the ether, for example, diethyl ether, diisopentyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-i-propyl ether, ethylene glycol-n-butyl ether , Ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol Monoethyl ether acetate, tetrahydrofuran, and the like;

Examples of the halogenated hydrocarbon include dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, and o-dichlorobenzene; As the hydrocarbon, for example, hexane, heptane, octane, benzene, toluene, xylene and the like; Each can be lifted.

Among these organic solvents, at least one selected from the group consisting of aprotic polar solvents and phenolic solvents (group A organic solvents), or at least one selected from group A organic solvents, alcohols, It is preferable to use a mixture with at least one member selected from the group consisting of ketones, esters, ethers, halogenated hydrocarbons and hydrocarbons (group B organic solvents). In the latter case, the use ratio of the group B organic solvent is preferably 50% by weight or less, more preferably 40% by weight or less, based on the total amount of the organic solvent of the group A and the organic solvent of the group B And more preferably 30% by weight or less.

It is preferable that the amount (a) of the organic solvent used is such that the total amount (b) of tetracarboxylic acid anhydride and diamine is 0.1 to 50% by weight relative to the total amount (a + b) of the reaction solution.

As described above, a reaction solution obtained by dissolving polyamic acid is obtained. This reaction solution may be provided as it is to the preparation of a liquid crystal aligning agent as it is, or may be provided to the preparation of a liquid crystal aligning agent after isolating the polyamic acid contained in the reaction solution, or the liquid crystal aligning agent may be prepared after purifying the isolated polyamic acid. You may provide to. When the polyamic acid is dehydrated and cyclized to form a polyimide, the reaction solution may be provided as it is to a dehydration cyclization reaction, or may be provided to a dehydration cyclization reaction after isolating the polyamic acid contained in the reaction solution, or the isolated polyamic acid. After purification, it may be provided in a dehydration ring closure reaction. The polyamic acid can be isolated and purified according to a known method.

<Synthesis of polyimide and polyimide>

The polyimide contained in the liquid crystal aligning agent of the present invention can be obtained by imidizing the polyamic acid synthesized as described above by dehydration and ring closure.

The polyimide may be a complete imide product of dehydration-closure of all the acidic structures of the precursor polyamic acid, or a partially imide structure in which only a part of the cancer acid structure is dehydrated and closed, and the cancer acid structure and the imide ring structure coexist. May be The imidation ratio of the polyimide in the present invention is preferably 30% or more, more preferably 40 to 99%, even more preferably 50 to 99%. This imidation rate is a percentage of the ratio of the number of imide ring structures to the total of the number of the maleic acid structures of the polyimide and the number of imide ring structures. Here, a part of the imide ring may be an isoimide ring.

The dehydration cyclization of the polyamic acid is preferably carried out by a method of heating the polyamic acid or by dissolving the polyamic acid in an organic solvent and adding a dehydrating agent and a dehydration cyclization catalyst to the solution to heat it as necessary. . Among these, it is preferable to use the latter method.

In the method of adding a dehydrating agent and a dehydrating ring-closure catalyst in the solution of the polyamic acid, as the dehydrating agent, for example, acid anhydrides such as acetic anhydride, propionic anhydride, and trifluoroacetic anhydride can be used. The amount of the dehydrating agent used is preferably 0.01 to 20 mol per 1 mol of the rock acid structure of the polyamic acid. As the dehydration ring closure catalyst, for example, tertiary amines such as pyridine, collidine, rutidine and triethylamine can be used. The amount of the dehydration ring-closed catalyst is preferably 0.01 to 10 mol per 1 mol of the dehydrating agent used. Examples of the organic solvent used for the dehydration ring-closure reaction include organic solvents exemplified as those used for the synthesis of polyamic acid. The reaction temperature of the dehydration ring-closure reaction is preferably 0 to 180 ° C, more preferably 10 to 150 ° C. The reaction time is preferably 1.0 to 120 hours, and more preferably 2.0 to 30 hours.

In this way, a reaction solution containing polyimide is obtained. This reaction solution may be provided to the preparation of a liquid crystal aligning agent as it is, or may be provided to the preparation of a liquid crystal aligning agent after removing the dehydrating agent and the dehydration ring closure catalyst from the reaction solution, or to the preparation of the liquid crystal aligning agent after isolating the polyimide. Alternatively, the purified polyimide may be purified and then provided to the preparation of a liquid crystal aligning agent. These purification operations can be performed according to a known method.

<Polyamlic acid ester>

The polyamic acid ester contained in the liquid crystal aligning agent of the present invention is, for example, [I] a method of synthesizing by reacting the polyamic acid obtained by the synthetic reaction with a hydroxyl group-containing compound, a halide, or an epoxy group-containing compound, [ Ⅱ] It can be obtained by a method of reacting a tetracarboxylic acid diester with a diamine, and a method of [III] reacting a tetracarboxylic acid diester dihalide with a diamine.

Here, examples of the hydroxyl group-containing compound used in method [I] include alcohols such as methanol, ethanol, and propanol; And phenols such as phenol and cresol. In addition, examples of the halide include methyl bromide, ethyl bromide, stearyl bromide, methyl chloride, stearyl chloride, 1,1,1-trifluoro-2-iodoethane, and the like, and epoxy group-containing compounds. As this, propylene oxide etc. are mentioned, for example. The tetracarboxylic acid diester used in the method [II] can be obtained, for example, by opening the tetracarboxylic acid anhydride exemplified in the synthesis of the polyamic acid using the alcohols described above. In addition, the tetracarboxylic acid diester dihalide used in the method [III] can be obtained by reacting the tetracarboxylic acid diester obtained as described above with a suitable chlorinating agent such as thionyl chloride. As the diamine used in the methods [II] and [III], diamines exemplified in the synthesis of the polyamic acid can be used. Further, the polyamic acid ester may have only a carboxylic acid ester structure, or may be a partial esterified product in which a carboxylic acid structure and a carboxylic acid ester structure coexist.

<Polymer solution viscosity and weight average molecular weight>

The polyamic acid, polyimide, and polyamic acid ester obtained as described above preferably have a solution viscosity of 10 to 3,000 mPa · s and a solution of 20 to 1,500 mPa · s when this is a 10% by weight solution. It is more preferable to have a viscosity. In addition, the solution viscosity (mPa · s) of the polymer is a positive solvent of the polymer (eg, γ-butyrolactone, N-methyl-2-pyrrolidone, 1,3-dimethyl-2- It is a value measured at 25 ° C using an E-type rotational viscometer for a polymer solution having a concentration of 10% by weight prepared using imidazolidinone, N-ethyl-2-pyrrolidone, and the like). Moreover, it is preferable that the weight average molecular weight of polystyrene conversion measured by gel permeation chromatography (GPC) with respect to the polyamic acid, polyimide, and polyamic acid ester contained in the liquid crystal aligning agent of the present invention is 500 to 100,000. It is more preferably 1,000 to 50,000.

<Polyorganosiloxane>

The polyorganosiloxane in the present invention can be obtained, for example, by hydrolyzing or hydrolyzing / condensing a hydrolyzable silane compound in the presence of a suitable organic solvent, water and catalyst.

Examples of the hydrolyzable silane compound used for the synthesis of the polyorganosiloxane include methyltrichlorosilane, methyltrimethoxysilane, methyltriethoxysilane, phenyltrichlorosilane, phenyltrimethoxysilane, and phenyltrie Methoxysilane, methyldichlorosilane, methyldimethoxysilane, methyldiethoxysilane, dimethyldichlorosilane, dimethyldimethoxysilane, dimethyldiethoxysilane, diphenyldichlorosilane, diphenyldimethoxysilane, diphenyldiethoxysilane, chlorodimethyl Silane, methoxydimethylsilane, ethoxydimethylsilane, chlorotrimethylsilane, bromotrimethylsilane, iodotrimethylsilane, methoxytrimethylsilane, ethoxytrimethylsilane, tetramethoxysilane, tetraethoxysilane, octadecyltrichloro Silane, octadecyltrimethoxysilane, vinyltrichlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, allyltrichlorosilane, Allyltrimethoxysilane, allyltriethoxysilane,

3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyl Dimethylmethoxysilane, 3-glycidoxypropyldimethylethoxysilane, 2-glycidoxyethyltrimethoxysilane, 2-glycidoxyethyltriethoxysilane, 2-glycidoxyethylmethyldimethoxysilane, 2 -Glycidoxyethylmethyldiethoxysilane, 2-glycidoxyethyldimethylmethoxysilane, 2-glycidoxyethyldimethylethoxysilane, 4-glycidoxybutyltrimethoxysilane, 4-glycidoxybutyltri Ethoxysilane, 4-glycidoxybutylmethyldimethoxysilane, 4-glycidoxybutylmethyldiethoxysilane, 4-glycidoxybutyldimethylmethoxysilane, 4-glycidoxybutyldimethylethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxy Silane, 3- (3,4-epoxycyclohexyl) propyltrimethoxysilane, 3- (3,4-epoxycyclohexyl) propyltriethoxysilane, (meth) acrylic acid (3-ethyloxetan-3-yl ) Methyl, (meth) acrylic acid (3-methyloxetan-3-yl) methyl,

3- (meth) acryloxypropyl trichlorosilane, 3- (meth) acryloxypropyl trimethoxysilane, 3- (meth) acryloxypropyl triethoxysilane, 2- (meth) acryloxyethyl trichlorosilane, 2- (meth) acryloxyethyltrimethoxysilane, 2- (meth) acryloxyethyltriethoxysilane, 4- (meth) acryloxybutyltrichlorosilane, 4- (meth) acryloxybutyltrimethoxysilane And 4- (meth) acryloxybutyltriethoxysilane. In addition, "(meth) acryloxy" means "acryloxy" and "methacryloxy".

Examples of the organic solvent that can be used in the synthesis of the polyorganosiloxane include hydrocarbons, ketones, esters, ethers, alcohols, and the like. Here, as said hydrocarbon, For example, toluene, xylene, etc .; Examples of the ketone include methyl ethyl ketone, methyl isobutyl ketone, methyl n-amyl ketone, diethyl ketone, cyclohexanone, and the like; Examples of the ester include ethyl acetate, n-butyl acetate, i-amyl acetate, propylene glycol monomethyl ether acetate, 3-methoxybutyl acetate, ethyl lactate, and the like; Examples of the ether include ethylene glycol dimethyl ether, ethylene glycol diethyl ether, tetrahydrofuran, dioxane, and the like; Examples of the alcohol include 1-hexanol, 4-methyl-2-pentanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol mono-n-propyl ether, and ethylene glycol mono-n-butyl ether. , Propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-propyl ether, and the like. Among these, it is preferable to use a water-insoluble organic solvent. Moreover, these organic solvents can be used individually by 1 type or in mixture of 2 or more types.

The amount of the organic solvent used when synthesizing the polyorganosiloxane is preferably 10 to 10,000 parts by weight, more preferably 50 to 1,000 parts by weight, based on 100 parts by weight of the total silane compound. In addition, the amount of water used in preparing the polyorganosiloxane is preferably 0.5 to 100 times mole, more preferably 1 to 30 times mole, with respect to the total silane compound used.

Examples of the catalyst that can be used in the synthesis of the polyorganosiloxane include acids, alkali metal compounds, organic bases, titanium compounds, and zirconium compounds. Here, examples of the acid include hydrochloric acid, sulfuric acid, nitric acid, formic acid, oxalic acid, acetic acid, trifluoroacetic acid, trifluoromethanesulfonic acid and phosphoric acid; Examples of the alkali metal compound include sodium hydroxide, potassium hydroxide, sodium methoxide, potassium methoxide, sodium ethoxide and potassium ethoxide; Examples of the organic base include primary and secondary organic amines such as ethylamine, diethylamine, piperazine, piperidine, pyrrolidine, and pyrrole, triethylamine, tri-n-propylamine, and tri-n -Tertiary organic amines such as butylamine, pyridine, 4-dimethylaminopyridine and diazabicycloundecene, quaternary organic amines such as tetramethylammonium hydroxide, and the like; Each can be lifted.

As the catalyst, an organic base is particularly preferred. The amount of the organic base used varies depending on the type of the organic base, reaction conditions such as temperature, and the like, and should be appropriately set. For example, it is preferably 0.01 to 3 times the molar amount of the total silane compound, and more preferably 0.05 to It is 1 times mole.

In the hydrolysis or hydrolysis / condensation reaction in preparing the polyorganosiloxane, one or two or more of the hydrolyzable silane compounds are dissolved in an organic solvent, and the obtained solution is mixed with an organic base and water, It is preferable to carry out, for example, heating by an oil bath or the like.

During the hydrolysis-condensation reaction, the heating temperature is preferably 130 ° C. or less, more preferably 40 to 100 ° C., preferably 0.5 to 12 hours, more preferably 1 to 8 hours. . During heating, the mixed solution may be stirred or placed under reflux.

After completion of the reaction, it is preferable to wash the organic solvent layer fractionated from the reaction solution with water. In this washing, it is preferable from the point of easy washing operation by washing with water containing a small amount of salt, for example, an aqueous ammonium nitrate solution of about 0.2% by weight or the like. Washing is performed until the water layer after washing becomes neutral, and then the organic solvent layer is dried with an desiccant such as anhydrous calcium sulfate and molecular sieve, if necessary, and then the solvent is removed to obtain a target polyorganosiloxane. You can. Moreover, you may use a commercial item as polyorganosiloxane in this invention.

As the polyorganosiloxane contained in the liquid crystal aligning agent of the present invention, a structure derived from the reactive compound is introduced into the side chain of the reactive polyorganosiloxane by reacting the reactive polyorganosiloxane and the reactive compound obtained by the condensation reaction. You can use the old one. Here, as a reactive polyorganosiloxane, polyorganosiloxane which has an epoxy group, an unsaturated double bond, a mercapto group, an amino group, etc. is mentioned, for example. In addition, examples of the reactive compound include a compound having a long chain alkyl group, a compound having a structure in which two or more rings (for example, a benzene ring or a cyclohexane ring) are connected, a compound having a steroid skeleton, and a compound having an unsaturated double bond And the like. Specifically, as the reactive compound, for example, the compounds described in Japanese Patent Application No. 2013-77493 can be used.

Moreover, reaction of a reactive polyorganosiloxane and a reactive compound can be performed according to the organic chemical ordinance. For example, when the reactive polyorganosiloxane has an epoxy group, a structure derived from the reactive compound can be introduced into the side chain of the reactive polyorganosiloxane by using carbonic acid as the reactive compound. In addition, when the reactive polyorganosiloxane has an unsaturated double bond, a structure derived from the reactive compound can be introduced into the side chain of the reactive polyorganosiloxane by using a compound having a mercapto group or an amino group as the reactive compound.

In the polyorganosiloxane in the present invention, the weight average molecular weight in terms of polystyrene measured by GPC is preferably 500 to 100,000, more preferably 1,000 to 30,000, and even more preferably 1,000 to 20,000. .

<Solvent>

The solvent contained in the liquid crystal aligning agent of the present invention contains at least a compound (p1) represented by the following formula (1) as a solvent component:

(In the formula (1), R ¹ to R ⁴ are each independently a linear or branched hydrocarbon group having 1 to 6 carbon atoms or a CC bond of the hydrocarbon group, from -O-, -COO- and -OCO- A group having at least one selected).

In R ¹ to R ⁴ of Formula (1), examples of the hydrocarbon group having 1 to 6 carbon atoms include a chain hydrocarbon group having 1 to 6 carbon atoms, an aliphatic hydrocarbon group, an aromatic hydrocarbon group, etc., which may be saturated or unsaturated. , Linear or branched. Specific examples of R ¹ to R ⁴ include, for example, alkyl groups having 1 to 6 carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, butyl group, pentyl group, and hexyl group; Monovalent unsaturated hydrocarbon groups including vinyl groups, allyl groups, and the like; And the like. Preferably, R ¹ to R ⁴ are chain hydrocarbon groups having 1 to 6 carbon atoms, more preferably alkyl groups having 1 to 6 carbon atoms, and more preferably methyl groups. Further, in the formula ^(1), R 1 ~R ⁴ it may be the same or different from each other.

As a preferable specific example of compound (p1), the compound (N, N, 2-trimethylpropionamide) represented by following formula (1-1) is mentioned, for example.

The content of the compound (p1) is preferably 0.1% by weight or more, more preferably 1% by weight or more, further preferably 5% by weight or more, and even more preferably 10% by weight with respect to the total amount of the solvent contained in the liquid crystal aligning agent. Particularly preferred is the above. The upper limit of the content is preferably 90% by weight or less, more preferably 85% by weight or less, and even more preferably 80 with respect to the total amount of the solvent contained in the liquid crystal aligning agent from the viewpoint of printability. It is less than weight%.

Moreover, the upper limit of the content of the compound (p1) is preferably 95% by weight or less, and more preferably 90% by weight or less, with respect to the total amount of the solvent contained in the liquid crystal aligning agent from the viewpoint of surface unevenness. In addition, the compound (p1) may contain N-methylisobutylamide, isobutylamide, isobutyronitrile, dimethylamine and the like as impurities. In such a case, about the preferable range of the content ratio of the compound (p1) described above, the amount of the compound (p1) containing such impurities will be defined.

[Other solvents]

As the solvent used in the preparation of the liquid crystal aligning agent of the present invention, other solvents other than the compound (p1) described above may be used. Examples of the other solvents include N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butyrolactam, N, N-dimethylformamide, N, N-dimethylacetamide, and 4-hydride Roxy-4-methyl-2-pentanone (diacetone alcohol), ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxy propionate, ethylene glycol methyl ether, ethylene glycol ethyl Ether, ethylene glycol-n-propyl ether, ethylene glycol-i-propyl ether, ethylene glycol-n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, di Ethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, dipropylene Glycol monomethyl ether (DPM), diisobutyl ketone, isoamyl propionate, isoamyl isobutylate, diisopentyl ether, ethylene carbonate, propylene carbonate, tert-butyl alcohol, tert-pentanol, 3-butoxy -N, N-dimethylpropanamide, 3-methoxy-N, N-dimethylpropanamide, 3-hexyloxy-N, N-dimethylpropanamide, isopropoxy-N-isopropyl-propionamide, n- Butoxy-N-isopropyl-propionamide, N-ethyl-2-pyrrolidone, N-propyl-2-pyrrolidone, N-butyl-2-pyrrolidone, N- (t-butyl) -2 -Pyrrolidone, N-pentyl-2-pyrrolidone, N-methoxypropyl-2-pyrrolidone, N-ethoxyethyl-2-pyrrolidone, N-methoxybutyl-2-pyrrolidone , 1,3-dimethyl-2-imidazolidinone, ethylene glycol diacetate, propylene glycol diacetate, diacetone alcohol, tert-butyl alcohol, tert-pentanol, and the like. Moreover, the other solvent can be used individually by 1 type or in mixture of 2 or more types.

The content of the other solvent is preferably 99% by weight or less, and more preferably, based on the total amount of the solvent contained in the liquid crystal aligning agent, from the viewpoint of sufficiently obtaining the effect of compounding the compound (p1). It is 95 weight% or less, More preferably, it is 80 weight% or less. In addition, from the viewpoint of improving the printability, the lower limit of the content of the other solvents is preferably 10% by weight or more, more preferably 15% by weight with respect to the total amount of the solvent contained in the liquid crystal aligning agent. And more preferably 20% by weight or more.

<Other additives>

The liquid crystal aligning agent of the present invention contains the above-described polymer and solvent, but may contain other additives as necessary. Examples of such other additives include polymers other than the above polymers, compounds having at least one epoxy group in the molecule (hereinafter referred to as "epoxy group-containing compounds"), functional silane compounds, radical generators, and the like. You can.

[Other polymers]

The above-mentioned other polymers can be used to improve solution properties and electrical properties. Examples of such other polymers include polyester, polyamide, cellulose derivative, polyacetal, polystyrene derivative, poly (styrene-phenylmaleimide) derivative, and poly (meth) acrylate. When the other polymer is added to the liquid crystal aligning agent, the blending ratio is preferably 50% by weight or less, more preferably 0.1 to 40% by weight, and 0.1 to 30% by weight relative to the total amount of polymer in the composition. Is more preferred.

[Epoxy group-containing compound]

The epoxy group-containing compound can be used to improve adhesion to the substrate surface in the liquid crystal alignment film. Here, as the epoxy group-containing compound, for example, ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycol Diether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, trimethylolpropane triglycidyl ether, 2,2-dibromoneopentyl glycol di Glycidyl ether, N, N, N ', N'-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylmethane, N, N-diglycidyl-benzylamine, N, N-diglycidyl-aminomethylcyclohexane, N, And N-diglycidyl-cyclohexylamine.

When adding these epoxy compounds to a liquid crystal aligning agent, the compounding ratio is preferably 40 parts by weight or less, more preferably 0.1 to 30 parts by weight, based on 100 parts by weight of the total of polymers contained in the liquid crystal aligning agent.

[Functional silane compound]

The said functional silane compound can be used for the purpose of improving the printability of a liquid crystal aligning agent. Examples of the functional silane compound include 3-aminopropyl trimethoxysilane, 3-aminopropyl triethoxysilane, 2-aminopropyl trimethoxysilane, 2-aminopropyl triethoxysilane, and N- (2 -Aminoethyl) -3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxy Silane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-triethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecan, 9-tri Methoxysilyl-3,6-diazanonyl acetate, 9-trimethoxysilyl-3,6-diazanonanoate methyl, N-benzyl-3-aminopropyl trimethoxysilane, N-phenyl-3-aminopropyl Trimethoxysilane, glycidoxymethyltrimethoxysilane, 2-glycidoxyethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, etc. Can.

When adding these functional silane compounds to a liquid crystal aligning agent, the blending ratio is preferably 2 parts by weight or less, more preferably 0.02 to 0.2 parts by weight, based on 100 parts by weight of the total polymer.

[Radical generator]

The radical generator is a compound capable of generating radicals by irradiation of radiation such as visible light, ultraviolet rays, far ultraviolet rays, electron beams, X-rays, and the like, and liquid crystal aligning agents (especially, for the purpose of promoting the reaction of radical-reactive compounds) It can be contained in the liquid crystal aligning agent for manufacture of a PSA mode type liquid crystal display element).

The radical generator is not particularly limited, and conventionally known compounds can be used. Specific examples of the radical generator include acetophenone, benzophenone, 1-hydroxycyclohexylphenylketone, 2,2-dimethoxy-2-phenylacetophenone, xanthone, fluorenone, benzaldehyde, anthraquinone, and tri Phenylamine, carbazole, 3-methylacetophenone, 4-chlorobenzophenone, myhila ketone, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 2-hydroxy -2-methyl-1-phenylpropan-1-one, 2,2-dimethoxy-1,2-diphenylethan-1-one, thioxanthone, 2-methyl-1- [4- (methylthio) phenyl ] -2-morpholino-propan-1-one, diphenyl (2,4,6-trimethoxybenzoyl) phosphine oxide, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl ) -Butanone 1,2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, 1,2-octanedione, 1- [4- ( Phenylthio)-, 2- (O-benzoyloxime)], ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O- Acetyloxime) And polymethylphenylsilane. The radical generator may be used alone or in combination of two or more.

When a radical generator is added to a liquid crystal aligning agent, the blending ratio is preferably 20 parts by weight or less, more preferably 0.1 to 5 parts by weight, based on 100 parts by weight of the total polymer.

Other additives to be included in the liquid crystal aligning agent include metal chelate compounds such as acetylacetone complexes of metals selected from aluminum, titanium, and zirconium or acetoacetic acid complexes, curing accelerators such as phenol group-containing compounds, surfactants, and molecules. Compounds having at least one oxetanyl group, antioxidants, and the like can be used therein.

The solid content concentration (the ratio of the total weight of components other than the solvent of the liquid crystal aligning agent to the total weight of the liquid crystal aligning agent) in the liquid crystal aligning agent of the present invention is appropriately selected in consideration of viscosity, volatility, and the like, but is preferably Is 1 to 10% by weight. That is, the liquid crystal aligning agent of the present invention is applied to the substrate surface as described below, and preferably heated to form a coating film which is a liquid crystal alignment film or a coating film to be a liquid crystal alignment film, but at this time, when the solid content concentration is less than 1% by weight , The film thickness of the coating film is too small to obtain a good liquid crystal alignment film. On the other hand, when the solid content concentration exceeds 10% by weight, the film thickness of the coating film becomes excessive and a good liquid crystal aligning film cannot be obtained, and the viscosity of the liquid crystal aligning agent increases, resulting in poor coating properties.

The range of particularly preferable solid content concentration differs depending on the method used when the liquid crystal aligning agent is applied to the substrate. For example, in the case of the spin coating method, a solid content concentration of 1.5 to 4.5% by weight is particularly preferable. In the case of the offset printing method, it is particularly preferable that the solid content concentration is in the range of 3 to 9% by weight, and thus the solution viscosity is in the range of 12 to 50 mPa · s. In the case of the inkjet method, it is particularly preferable that the solid content concentration is in the range of 1 to 5% by weight, and accordingly, the solution viscosity is in the range of 3 to 15 mPa · s.

The temperature when the liquid crystal aligning agent of the present invention is prepared is preferably 10 to 50 ° C, and more preferably 20 to 30 ° C.

<Liquid crystal alignment film and liquid crystal display element>

The liquid crystal aligning film of this invention is formed by the liquid crystal aligning agent prepared as mentioned above. Moreover, the liquid crystal display element of this invention is equipped with the liquid crystal aligning film formed using the liquid crystal aligning agent of this invention. The driving mode to which the liquid crystal display element of the present invention is applied is not particularly limited, and can be applied to various driving modes such as TN type, STN type, IPS type, FFS type, VA type, and MVA type. Below, the manufacturing method of the liquid crystal display element of this invention is demonstrated, and the manufacturing method of the liquid crystal aligning film of this invention is demonstrated among the description.

The liquid crystal display element of the present invention can be produced, for example, by the following steps (1) to (3). In the step (1), the substrate used is different depending on the desired driving mode. Steps (2) and (3) are common to each drive mode.

[Process (1): Formation of coating film]

First, the liquid crystal aligning agent of the present invention is applied onto a substrate, and then a coated film is formed on the substrate by heating the coated surface.

(1-1) In the case of manufacturing a TN type, STN type or VA type liquid crystal display device, the present invention is formed on a surface of each transparent conductive film formed by pairing two substrates on which a patterned transparent conductive film is formed. The liquid crystal aligning agent of is preferably applied by an offset printing method, a spin coating method, a roll coater method or an inkjet printing method, respectively. As a coating method of a liquid crystal aligning agent, it can apply suitably to an offset printing method among these. Here, as the substrate, for example, glass such as float glass and soda glass; A transparent substrate made of plastic such as polyethylene terephthalate, polybutylene terephthalate, polyether sulfone, polycarbonate, and poly (alicyclic olefin) can be used. As a transparent conductive film formed on one surface of the substrate, an NESA film made of tin oxide (SnO ₂ ) (registered trademark of PPG, USA), an ITO film made of indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ), or the like can be used. You can. To obtain a patterned transparent conductive film, for example, after forming a transparent conductive film without a pattern, a method of forming a pattern by photoetching, a method of using a mask having a desired pattern when forming the transparent conductive film, etc. have. In the application of the liquid crystal aligning agent, in order to further improve the adhesion between the substrate surface and the transparent conductive film and the coating film, a functional silane compound, a functional titanium compound, or the like is applied to the surface where the coating film is to be formed on the substrate surface. You may perform pre-coating beforehand.

After application of the liquid crystal aligning agent, preheating (prebaking) is preferably performed for the purpose of preventing liquid flow of the applied aligning agent. The pre-baking temperature is preferably 30 to 200 ° C, more preferably 40 to 150 ° C, and particularly preferably 40 to 100 ° C. The pre-baking time is preferably 0.25 to 10 minutes, and more preferably 0.5 to 5 minutes. Thereafter, a sintering (post-baking) process is carried out with the aim of completely removing the solvent and thermally imidizing the acid structure present in the polymer as necessary. The firing (post-baking) temperature is preferably 80 to 300 ° C, more preferably 120 to 250 ° C. The post-baking time is preferably 5 to 200 minutes, and more preferably 10 to 100 minutes. In this way, the film thickness of the formed film is preferably 0.001 to 1 μm, and more preferably 0.005 to 0.5 μm.

(1-2) In the case of manufacturing an IPS type or FFS type liquid crystal display device, the electrode formation surface of a substrate on which an electrode made of a transparent conductive film or a metal film patterned in a comb shape is formed is opposed to an electrode on which an electrode is not formed. The liquid crystal aligning agent of this invention is apply | coated to one surface of a board | substrate, respectively, and a coating film is formed by heating each application surface next. At this time, the material of the substrate and the transparent conductive film used, the coating method, the heating conditions after application, the patterning method of the transparent conductive film or the metal film, the pretreatment of the substrate and the preferred film thickness of the formed coating film are the same as in (1-1) above. As the metal film, for example, a film made of metal such as chromium can be used.

In any of the above (1-1) and (1-2), after coating the liquid crystal aligning agent on the substrate, a coating film serving as an alignment film is formed by removing the organic solvent. At this time, in the case of the polymer contained in the liquid crystal aligning agent of the present invention is a polyamic acid, an imidized polymer having an imide ring structure and a rock acid structure, or a polymer having a rock acid ester structure and a rock acid structure, after the coating film is formed, The dehydration cyclization reaction may proceed by heating, and may be a more imidized coating film.

[Process (2): Orientation ability imparting treatment]

Subsequently, the coating film formed on the substrate is subjected to rubbing treatment or light irradiation treatment as necessary to impart liquid crystal alignment ability to the coating film.

First, in the case of manufacturing a TN type, STN type, IPS type or FFS type liquid crystal display element for rubbing treatment, the coating film formed in the step (1) is made of, for example, fibers such as nylon, rayon, and cotton. The rubbing treatment is performed by rubbing in a certain direction with a roll of cloth. Thereby, the alignment ability of the liquid crystal molecules is imparted to the coating film to become a liquid crystal alignment film. On the other hand, when manufacturing a VA type liquid crystal display element, although the coating film formed in the said process (1) can be used as a liquid crystal aligning film as it is, you may perform a rubbing process with respect to this coating film.

In addition, with respect to the liquid crystal aligning film after the rubbing treatment, a process of changing the pretilt angle of a part of the region of the liquid crystal aligning film by irradiating ultraviolet rays to a part of the liquid crystal aligning film, or after forming a resist film on a part of the surface of the liquid crystal aligning film After the rubbing treatment is performed in a direction different from the rubbing treatment, a treatment for removing the resist film may be performed, and the liquid crystal aligning film may have a different liquid crystal aligning ability for each region. In this case, it is possible to improve the viewing characteristics of the obtained liquid crystal display element.

On the other hand, in the case of the light irradiation process (photo-alignment method), the substrate after forming the coating film is irradiated with radiation of polarized light or unpolarized light onto the coated film surface to impart liquid crystal alignment ability to the coated film. Here, as the radiation, for example, ultraviolet rays or visible rays containing light having a wavelength of 150 to 800 nm can be used. Among them, ultraviolet rays containing light having a wavelength of 300 nm to 400 nm are preferred. When the radiation to be used is polarized (linearly polarized or partially polarized), the light irradiation direction may be perpendicular to the coated film surface, or may be inclined to impart a pretilt angle. On the other hand, when irradiating non-polarized radiation, it is necessary to perform light irradiation from the inclined direction with respect to the coated surface.

As the light source, for example, a low pressure mercury lamp, a high pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an excimer laser, or the like can be used. Ultraviolet rays in the above-mentioned preferred wavelength range can be obtained by, for example, means for using a light source in combination with a filter, a diffraction grating, or the like. The radiation dose is preferably 1 J / m 2 or more and less than 20,000 J / m 2, and more preferably 10 to 10,000 J / m 2. In addition, according to the photo-alignment treatment, a liquid crystal aligning ability is imparted to the coated film by irradiating the coated film formed on the substrate to produce a liquid crystal aligning film.

[Process (3): Construction of liquid crystal cell]

A liquid crystal cell is manufactured by preparing two substrates on which a liquid crystal alignment film is formed as described above, and disposing liquid crystals between two substrates arranged oppositely. In order to manufacture a liquid crystal cell, the following two methods are mentioned, for example.

The first method is a conventionally known method. First, two substrates are arranged to face each other via a gap (cell gap) so that the respective liquid crystal alignment films face each other, and the peripheral portions of the two substrates are bonded using a sealing agent, and are divided by the substrate surface and the sealing agent. A liquid crystal cell can be manufactured by injecting and filling a liquid crystal into a cell gap and sealing the injection hole. Further, the second method is a method called ODF (One Drop Fill) method. After apply | coating the sealing agent of ultraviolet light hardening to a predetermined place on one of the two board | substrates which formed the liquid crystal aligning film, for example, after dropping a liquid crystal in predetermined places on the liquid crystal aligning film surface, liquid crystal aligning film A liquid crystal cell can be produced by bonding the other substrate so as to face this, spreading the liquid crystal on the entire surface of the substrate, and then irradiating ultraviolet light on the entire surface of the substrate to cure the sealing agent. In the case of any method, the liquid crystal cell produced as described above is further heated to a temperature at which the used liquid crystal takes an isotropic phase, and then gradually cooled to room temperature, thereby removing flow orientation during liquid crystal charging. desirable.

As the sealing agent, for example, an epoxy resin containing an aluminum oxide sphere as a curing agent and a spacer can be used.

Examples of the liquid crystals include nematic liquid crystals and smectic liquid crystals, and among them, nematic liquid crystals are preferable, and for example, Cipro-based liquid crystals, sub clock crystals, biphenyl-based liquid crystals, phenylcyclohexane-based liquid crystals, and ester-based liquid crystals , Terphenyl-based liquid crystals, biphenylcyclohexane-based liquid crystals, pyrimidine-based liquid crystals, dioxane-based liquid crystals, bicyclooctane-based liquid crystals, and cuban-based liquid crystals. Moreover, cholesteric liquid crystals, such as cholesteryl chloride, cholesteryl nonate, and cholesteryl carbonate; A chiral agent sold as trade names "C-15" and "CB-15" (manufactured by Merck); Ferroelectric liquid crystals such as p-decyloxybenzylidene-p-amino-2-methylbutylcinnamate and the like may be added and used.

And the liquid crystal display element of this invention can be obtained by bonding a polarizing plate to the outer surface of a liquid crystal cell. As a polarizing plate bonded to the outer surface of a liquid crystal cell, a polarizing plate called a "H film" which absorbed iodine while stretching-oriented polyvinyl alcohol was sandwiched with a cellulose acetate protective film or a polarizing plate made of the H film itself. have.

In addition, when the rubbing process is applied to the coating film, the two substrates are arranged to face each other so that the rubbing direction in each coating film is a predetermined angle with each other, for example, orthogonal or antiparallel. In addition, when light irradiation is performed with respect to the coating film, if the liquid crystal alignment film is horizontally oriented, the angle formed by the polarization direction of the irradiated linearly polarized radiation on the two substrates on which the liquid crystal alignment film is formed and the angle between each substrate and the polarizing plate By adjusting, it is possible to obtain a liquid crystal display element having a TN type or STN type liquid crystal cell. On the other hand, when the liquid crystal aligning film is vertically oriented, the cells are configured so that the directions of the axes of easy alignment in the two substrates on which the liquid crystal aligning film is formed are parallel, and the polarizing plate is formed with the polarizing direction and 45. By bonding to form an angle of °, a liquid crystal display device having a vertically aligned liquid crystal cell can be obtained.

The liquid crystal display element of the present invention may be an element having a liquid crystal alignment film provided with a pretilt angle by PSA (Polymer Sustained Alignment) technology. Such a PSA mode liquid crystal display element can be produced, for example, by a method including the following steps (I-1) to (I-3).

(I-1) A step of applying a liquid crystal aligning agent onto the conductive films of a pair of substrates having a conductive film, respectively, and then heating them to form a coating film,

(I-2) a step of arranging the pair of substrates on which the coating film is formed so that the coating films face each other via a liquid crystal layer containing a liquid crystal and a photopolymerizable compound; and

(I-3) A method comprising the step of irradiating light to a liquid crystal cell in a state in which a voltage is applied between conductive films of a pair of substrates.

For the above step (I-1), the material of the substrate and the transparent conductive film used, the coating method, the heating conditions after application, the patterning method of the transparent conductive film or metal film, the pretreatment of the substrate and the preferred film thickness of the formed coating film are described above. Same as (1-1). Moreover, the coating film formed in the said process (I-1) may be provided to the following process as it is, or may be provided to the following process after performing rubbing treatment to the coating film surface as needed.

In the step (I-2), when the liquid crystal is charged or dropped in the step (3), a liquid crystal layer containing a liquid crystal and a photopolymerizable compound is formed by using a photopolymerizable compound (photopolymerizable monomer) together with the liquid crystal. A liquid crystal cell is constructed in the same manner as in the above step (3) except for the above. As the photopolymerizable compound, a compound having a functional group capable of radical polymerization such as an acryloyl group, a methacryloyl group and a vinyl group can be used. From the viewpoint of reactivity, it is preferable that it is polyfunctional, and it is more preferable to have two or more of at least one of acryloyl group and methacryloyl group in the molecule. In addition, from the viewpoint of stably maintaining the alignment property of the liquid crystal molecules, it is preferable to use a compound having at least one ring of a cyclohexane ring or a benzene ring in the molecule as a photopolymerizable compound in a total of two or more. Moreover, a conventionally well-known thing can be used as such a photopolymerizable compound. The blending ratio of the photopolymerizable compound is preferably 0.1 to 0.5% by weight relative to the total amount of the liquid crystal compound used.

In the step (I-3), after the liquid crystal cell is constructed, the liquid crystal cell is irradiated with a voltage while a voltage is applied between the conductive films of the pair of substrates. The voltage applied here can be, for example, DC or AC of 5 to 50V. The description of the photo-alignment method can be applied to the wavelength and the type of light source to be irradiated. The irradiation amount of light is preferably 1,000 J / m 2 or more and less than 200,000 J / m 2, more preferably 1,000 to 150,000 J / m 2. In addition, according to such a PSA treatment, by irradiating light onto the coating film formed on the substrate, the liquid crystal alignment ability is imparted to the coating film to produce a liquid crystal alignment film.

Thereafter, by bonding the polarizing plate to the outer surface of the liquid crystal cell, the liquid crystal display element of the present invention can be obtained. The above description can be applied to the description of the polarizing plate.

<Phase difference film>

In the case of manufacturing the retardation film using the liquid crystal aligning agent of the present invention, it is possible to form a uniform liquid crystal aligning film while suppressing the generation of dust and static electricity during the process, and by using a suitable photomask when irradiating radiation, the substrate It is preferable to use a photo-alignment method in that a plurality of regions having different liquid crystal alignment directions can be arbitrarily formed on the image. For example, a retardation film can be produced by passing through the following steps (II-1) to (II-3).

[Process (II-1): Formation of coating film by liquid crystal aligning agent]

First, the liquid crystal aligning agent of the present invention is applied on a substrate to form a coating film. As the substrate used herein, a transparent substrate made of synthetic resins such as triacetyl cellulose (TAC), polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polyamide, polyimide, polymethylmethacrylate, and polycarbonate Can be suitably illustrated. Among these, TAC is generally used as a protective layer of a polarizing film in a liquid crystal display element. In addition, polymethyl methacrylate can be preferably used as a substrate for a retardation film in that the solvent has low hygroscopicity, good optical properties, and low cost. Further, for the substrate used for the application of the liquid crystal aligning agent, in order to further improve the adhesion between the substrate surface and the coating film, a conventionally known pre-treatment may be performed on the surface of the substrate forming the coating film.

In many cases, a retardation film is used in combination with a polarizing film. At this time, it is necessary to precisely control the angle with respect to the polarization axis of the polarizing film in a specific direction so that the expected optical properties can be exhibited, and then attach the retardation film. Therefore, here, by forming a liquid crystal alignment film having a liquid crystal alignment ability in a direction of a predetermined angle on a substrate such as a TAC film or polymethyl methacrylate, a step of bonding the retardation film onto the polarizing film while controlling the angle. Can be omitted. Moreover, according to this, it can contribute to the improvement of productivity of a liquid crystal display element. In order to form the liquid crystal aligning film which has liquid crystal aligning ability in the direction of a predetermined angle, it is preferable to perform by the photo-alignment method using the liquid crystal aligning agent of this invention.

The application of the liquid crystal aligning agent onto the substrate can be performed by an appropriate coating method, for example, roll coater method, spinner method, printing method, inkjet method, bar coater method, extrusion die method, direct gravure coater method, chamber Doctor coater method, offset gravure coater method, 1 roll kiss coater method, reverse kiss coater method using small gravure roll, 3 reverse roll coater method, 4 reverse roll coater method, slot die method, air The doctor coater method, forward rotation roll coater method, blade coater method, knife coater method, impregnation coater method, MB coater method, MB reverse coater method and the like can be adopted.

After coating, the coated surface is heated (baked) to form a coating film. The heating temperature at this time is preferably 40 to 150 ° C, and more preferably 80 to 140 ° C. The heating time is preferably 0.1 to 15 minutes, and more preferably 1 to 10 minutes. The film thickness of the coating film formed on the substrate is preferably 1 to 1,000 nm, more preferably 5 nm to 500 nm.

[Process (Ⅱ-2): Light irradiation process]

Subsequently, light is irradiated to the coating film formed on the substrate as described above to impart liquid crystal alignment ability to the coating film. Thus, a liquid crystal alignment film is produced on the substrate. The description of the photo-alignment treatment in the above step (2) can be applied to the description of the wavelength of light, the type of light, and the light source used here. The irradiation amount of light is preferably 0.1 to 1,000 mJ / cm 2, more preferably 1 to 500 mJ / cm 2, and even more preferably 2 to 200 mJ / cm 2.

[Process (II-3): Formation of liquid crystal layer]

Subsequently, a polymerizable liquid crystal is applied and cured on the coated film after light irradiation as described above. Thereby, a coating film (liquid crystal layer) containing a polymerizable liquid crystal is formed. The polymerizable liquid crystal used herein is a liquid crystal compound or a liquid crystal composition that polymerizes by at least one treatment during heating and light irradiation. As such a polymerizable liquid crystal, a conventionally known one can be used, and specifically, for example, Non-Patent Document 1 ("UV curable liquid crystal and its application", liquid crystal, Volume 3, No. 1 (1999), pp34- And the nematic liquid crystal described in 42). In addition, cholesteric liquid crystals; Discotic liquid crystal; Twisted nematic alignment type liquid crystal to which chiral agent is added may be sufficient. The polymerizable liquid crystal may be a mixture of a plurality of liquid crystal compounds. The polymerizable liquid crystal may also be a composition containing a known polymerization initiator, a suitable solvent, and the like.

In order to apply the polymerizable liquid crystal as described above on a coating film formed by using a liquid crystal aligning agent, suitable coating methods such as a bar coater method, a roll coater method, a spinner method, a printing method, and an inkjet method can be employed.

Subsequently, the coating film of the polymerizable liquid crystal formed as described above is subjected to one or more treatments selected from heating and light irradiation to cure the coating film to form a liquid crystal layer. It is preferable to perform such a treatment superposedly in that good orientation is obtained.

The heating temperature of the coating film should be appropriately selected depending on the type of the polymerizable liquid crystal used. For example, when using RMS03-013C manufactured by Merck, it is preferable to heat at a temperature in the range of 40 to 80 ° C. The heating time is preferably 0.5 to 5 minutes.

As the irradiation light, non-polarized ultraviolet light having a wavelength in the range of 200 to 500 nm can be preferably used. The light irradiation amount is preferably 50 to 10,000 mJ / cm 2, and more preferably 100 to 5,000 mJ / cm 2.

The thickness of the liquid crystal layer to be formed is appropriately set in accordance with desired optical properties. For example, in the case of manufacturing a 1/2 wavelength plate in visible light having a wavelength of 540 nm, a thickness such that the phase difference of the formed retardation film is 240 to 300 nm is selected, and if it is a 1/4 wavelength plate, the phase difference is The thickness is selected to be 120-150 nm. The thickness of the liquid crystal layer in which the desired phase difference is obtained varies depending on the optical properties of the polymerizable liquid crystal used. For example, when Merck RMS03-013C is used, the thickness for producing a quarter wave plate is in the range of 0.6 to 1.5 µm.

The retardation film obtained as described above can be preferably applied as a retardation film of a liquid crystal display element. The liquid crystal display device to which the retardation film manufactured using the liquid crystal aligning agent of the present invention is applied is not limited in its driving method, and for example, various known types such as TN type, STN type, IPS type, FFS type, VA type, etc. Can be applied to the system. The said retardation film is used by attaching the surface of the substrate side in a retardation film with respect to the outer surface of the polarizing plate arrange | positioned on the viewing side of a liquid crystal display element. Therefore, it is preferable that the substrate of the retardation film is made of TAC or an acrylic substrate, and the substrate of the retardation film is an aspect that also functions as a protective film of the polarizing film.

In addition, there is a roll-to-roll method as a method of producing a retardation film on an industrial scale. This method is a process of unwinding a film from a wound body of a long-form base film, forming a liquid crystal alignment film on the unwound film, treating by applying a polymerizable liquid crystal on the liquid crystal alignment film, and curing as necessary. It is a method of performing the process of laminating a film in a continuous process, and recovering the film after passing through these processes as a wound body. The retardation film formed using the liquid crystal aligning agent of the present invention has good adhesion to a substrate, and even when it is stored as a wound body, the liquid crystal alignment film and the substrate are unlikely to peel off. Therefore, it is possible to suppress a decrease in product yield when manufacturing a retardation film by a roll-to-roll method.

The liquid crystal display device of the present invention can be effectively applied to various devices, for example, watches, portable games, word processors, notebook PCs, car navigation systems, camcorders, PDAs, digital cameras, mobile phones, smart phones It can be used for display devices such as phones, various monitors, and liquid crystal televisions.

[Example]

Hereinafter, the present invention will be described in more detail by examples, but the present invention is not limited to these examples.

The solution viscosity of each polymer solution in the synthesis example, the imidation ratio of the polyimide, the weight average molecular weight, and the epoxy equivalent were measured by the following method.

[Solution viscosity of polymer solution]

The solution viscosity (mPa · s) of the polymer solution was measured at 25 ° C. using an E-type rotational viscometer for the solution adjusted to a polymer concentration of 10% by weight using a predetermined solvent.

[Imidization rate of polyimide]

The solution of polyimide was poured into pure water, and the obtained precipitate was sufficiently dried under reduced pressure at room temperature, dissolved in deuterated dimethyl sulfoxide, and ¹ H-NMR was measured at room temperature using tetramethylsilane as a reference material. From the obtained ¹ H-NMR spectrum, the imidation rate [%] was obtained by the following formula (1):

Imidation rate [%] = {(1-A ¹ ) / (A ² × α)} × 100. (One)

(In Formula (1), A ¹ is the peak area derived from the proton of the NH group appearing near 10 ppm of chemical shift, A ² is the peak area derived from other protons, and α is the precursor of the polymer (polyamic acid). The ratio of the number of other protons to one proton of the NH group).

[Weight average molecular weight of polymer]

The weight average molecular weight is a polystyrene conversion value measured by gel permeation chromatography under the following conditions.

Column: Tosoh Corporation, TSKgelGRCXLⅡ

Solvent: Tetrahydrofuran

Temperature: 40 ℃

Pressure: 68kgf / ㎠

[Epoxy equivalent]

The epoxy equivalent was measured by the hydrochloric acid-methylethylketone method described in JIS C 2105.

<Synthesis of polymer (A)>

[Synthesis Example 1: Synthesis of polyimide (PI-1)]

As tetracarboxylic acid anhydride, 22.4g (0.1 mol) of 2,3,5-tricarboxycyclopentyl acetic anhydride, 8.6 g (0.08 mol) of p-phenylenediamine as diamine and 0.03 mol of 3,5-diaminobenzoic acid 10.5 g (0.02 mol) of Neil was dissolved in 166 g of N-methyl-2-pyrrolidone (NMP) and reacted at 60 ° C for 6 hours to obtain a solution containing 20% by weight of polyamic acid. A small amount of the obtained polyamic acid solution was aliquoted, and NMP was added to measure the solution viscosity as a solution having a polyamic acid concentration of 10% by weight, which was 90 mPa · s.

Subsequently, NMP was added to the obtained polyamic acid solution to obtain a solution having a polyamic acid concentration of 7% by weight, 11.9 g of pyridine and 15.3 g of acetic anhydride were added, and dehydration and ring closure reaction was performed at 110 ° C for 4 hours. After the dehydration cyclization reaction, the solvent in the system is replaced with a solvent in a new NMP (the pyridine and acetic anhydride used for the dehydration cyclization reaction are removed out of the system by this operation, hereinafter the same), and polyimide having an imidation rate of about 68% (PI- A solution containing 1% by weight of 26% was obtained. A small amount of the obtained polyimide solution was aliquoted, NMP was added, and the solution viscosity measured as a solution having a polyimide concentration of 10% by weight was 45 mPa · s. Then, the reaction solution was poured into a large excess of methanol to precipitate the reaction product. The precipitate was washed with methanol and dried under reduced pressure at 40 ° C for 15 hours to obtain polyimide (PI-1).

[Synthesis Example 2: Synthesis of polyimide (PI-2)]

2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4,6: 8-2 anhydride 24.9g (0.10 mol) as tetracarboxylic acid anhydride, p-phenylenediamine 8.6 as diamine g (0.08 mol) and 10.4 g (0.02 mol) of 3,5-diaminobenzoic acid cholesterol, were dissolved in 176 g of NMP, and reacted at 60 ° C for 6 hours to obtain a solution containing 20% by weight of polyamic acid. . A small amount of the obtained polyamic acid solution was aliquoted, and the solution viscosity measured by adding NMP as a 10% by weight polyamic acid concentration was 103 mPa · s.

Subsequently, NMP was added to the obtained polyamic acid solution to obtain a solution having a polyamic acid concentration of 7% by weight, 11.9 g of pyridine and 15.3 g of acetic anhydride were added, and dehydration and ring closure reaction was performed at 110 ° C for 4 hours. After the dehydration cyclization reaction, the solvent in the system was replaced by a new NMP to obtain a solution containing 26% by weight of polyimide (PI-2) having an imidation ratio of about 71%. A small amount of the obtained polyimide solution was aliquoted, and the solution viscosity measured by adding NMP as a solution having a polyimide concentration of 10% by weight was 57 mPa · s. Then, the reaction solution was poured into a large excess of methanol to precipitate the reaction product. The precipitate was washed with methanol and dried under reduced pressure at 40 ° C for 15 hours to obtain polyimide (PI-2).

[Synthesis Example 3: Synthesis of polyimide (PI-3)]

2,3,5-tricarboxycyclopentyl acetic anhydride 22.4g (0.1 mol) as tetracarboxylic acid anhydride, 3- (2,4-diaminophenoxy) cholestane 14.8g (0.03 mol) as diamine, meta 4.73 g (0.02 mol) of 2- (2,4-diaminophenoxy) ethyl acrylate (a compound represented by the following formula (R-2)) and 1- (4-aminophenyl) -2,3-dihydro 13.3 g (0.05 mol) of -1,3,3-trimethyl-1H-inden-5-amine was dissolved in 221 g of NMP, and reacted at 60 ° C for 6 hours to obtain a solution containing 20% by weight of polyamic acid. A small amount of the obtained polyamic acid solution was aliquoted, NMP was added, and the solution viscosity measured as a solution having a polyamic acid concentration of 10% by weight was 92 mPa · s.

Subsequently, NMP was added to the obtained polyamic acid solution to obtain a solution having a polyamic acid concentration of 7% by weight, and 7.9 g of pyridine and 10.2 g of acetic anhydride were added to perform a dehydration ring closure reaction at 110 ° C for 4 hours. After the dehydration ring-closure reaction, the solvent in the system was replaced by a new NMP to obtain a solution containing 25% by weight of polyimide (PI-3) having an imidation ratio of about 48%. A small amount of the obtained polyimide solution was fractionated, NMP was added, and the solution viscosity measured as a solution having a polyimide concentration of 10% by weight was 47 mPa · s. Then, the reaction solution was poured into a large excess of methanol to precipitate the reaction product. The precipitate was washed with methanol and dried under reduced pressure at 40 ° C for 15 hours to obtain polyimide (PI-3).

[Synthesis Example 4: Synthesis of polyamic acid (PA-1)]

1,2,3,4-cyclobutane tetracarboxylic acid anhydride 200 g (1.0 mol) as tetracarboxylic acid anhydride, 2,2'-dimethyl-4,4'-diaminobiphenyl 210 g (1.0 mol) as diamine Was dissolved in a mixed solvent of 370 g of NMP and 3,300 g of γ-butyrolactone, and reacted at 40 ° C for 3 hours to obtain a polyamic acid solution having a solid content concentration of 10% by weight and a solution viscosity of 160 mPa · s. Subsequently, this polyamic acid solution was poured into a large excess of methanol to precipitate the reaction product. The precipitate was washed with methanol and dried under reduced pressure at 40 ° C for 15 hours to obtain polyamic acid (PA-1).

[Synthesis Example 5: Synthesis of polyamic acid (PA-2)]

2,3,5-tricarboxycyclopentyl acetic anhydride 7.0g (0.031 mol) as tetracarboxylic acid anhydride, compound (r1) 13g (2,3,5-tri) represented by the following formula (R-1) as diamine A solution containing 20% by weight of polyamic acid (PA-3) was obtained by dissolving carboxycyclopentyl acetic acid 2 equivalent to 1 mole per 1 mole of NMP in 80 g of NMP and reacting at 60 ° C for 4 hours. . The solution viscosity of this polyamic acid solution was 2,000 mPa · s. In addition, compound (r1) was synthesized according to the description of JP-A-2011-100099. Subsequently, this polyamic acid solution was poured into a large excess of methanol to precipitate the reaction product. The precipitate was washed with methanol and dried under reduced pressure at 40 ° C for 15 hours to obtain polyamic acid (PA-2).

[Synthesis Example 6: Synthesis of polyamic acid (PA-3)]

In a 50 ml four-necked flask with a stirrer and nitrogen introduction tube, 0.60 g (2.0 mmol) of 1,3-bis (4-aminophenethyl) urea (BAPU) as diamine and p-phenylenediamine (p-PDA) 1.95 g (18.0 mmol) was added, and 30 g of N, N, 2-trimethylpropionamide was added and dissolved by stirring while sending nitrogen. While stirring this diamine solution, 3.70 g (18.9 mmol) of 1,2,3,4-cyclobutanetetracarboxylic acid anhydride as tetracarboxylic acid anhydride was added, and N was added so that the solid content concentration was 12% by weight. N, 2-trimethylpropionamide was added and stirred under nitrogen atmosphere at room temperature for 4 hours to obtain a solution of polyamic acid (PA-3).

[Synthesis Example 7: Synthesis of polyamic acid (PA-4)]

1,2,3,4-cyclobutane tetracarboxylic acid anhydride 19.61 g (0.1 mol) as tetracarboxylic acid anhydride and 4,4'-diaminodiphenylamine (4,4'DADPA) as diamine 18.73 g (0.094 mol) was mixed in 345.1 g of N, N, 2-trimethylpropionamide and reacted at room temperature for 5 hours. The polymerization reaction proceeded easily and uniformly to obtain polyamic acid (PA-4).

[Synthesis Example 8: Synthesis of polyamic acid (PA-5)]

14.64 g (0.072 mol) of 2,4-diamino-N, N-diallylaniline as diamine, 2.96 g (0.016 mol) of n-dodecylamine as monoamine, and 1,2,3 as tetraanhydride 2 anhydride 15.69 g (0.08 mol) of, 4-cyclobutanetetracarboxylic acid anhydride was reacted in 300 g of N, N, 2-trimethylpropionamide at room temperature for 4 hours to obtain a solution of polyamic acid (PA-5).

[Synthesis Example 9: Synthesis of polyamic acid (PA-6)]

10.36 g of bis [2- (4-aminophenyl) ethyl] hexane diacid as diamine and 19.63 g of pyromellitic dianhydride as tetracarboxylic acid anhydride in 170 g of N, N, 2-trimethylpropionamide 4 at room temperature Time reaction allowed to obtain a solution of polyamic acid (PA-6).

[Synthesis Example 10: Synthesis of polyamic acid (PA-7)]

Bis [2- (4-aminophenyl) ethyl] hexane diacid 11.88g as diamine, compound 6.8g represented by the following formula (R-3), 1,2,3,4-cyclobutanetetra as tetracarboxylic acid anhydride 11.27 g of carboxylic acid anhydride was reacted in 170 g of N, N, 2-trimethylpropionamide at room temperature for 4 hours to obtain a solution of polyamic acid (PA-7).

[Synthesis Example 11: Synthesis of polyorganosiloxane (APS-1)]

In a reaction vessel equipped with a stirrer, thermometer, dropping funnel and reflux cooling tube, 100.0 g 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane (ECETS), 500 g methylisobutyl ketone and 10.0 g triethylamine And mixed at room temperature. Subsequently, 100 g of deionized water was added dropwise from the dropping funnel over 30 minutes, and then reacted at 80 ° C for 6 hours while stirring under reflux. After the completion of the reaction, the organic layer was taken out, washed with 0.2% by weight aqueous ammonium nitrate solution until the water after washing was neutral, and then distilled off the solvent and water under reduced pressure to remove the reactive polyorganosiloxane (EPS-1 ) Was obtained as a viscous transparent liquid. As a result of performing ¹ H-NMR analysis on this reactive polyorganosiloxane, a peak based on an epoxy group was obtained in the vicinity of the chemical shift (δ) = 3.2 ppm, and the side reaction of the epoxy group was observed during the reaction. It was confirmed that it did not happen. The obtained reactive polyorganosiloxane had a weight average molecular weight Mw of 3,500 and an epoxy equivalent of 180 g / mol.

Subsequently, in a 200 mL three-necked flask, 10.0 g of reactive polyorganosiloxane (EPS-1), 30.28 g of methyl isobutyl ketone as a solvent, 3.98 g of 4-dodecyloxybenzoic acid as a reactive compound, and UCAT 18X (as a catalyst) Product name and 0.10 g of San Apron Co., Ltd. were added and the reaction was performed at 100 ° C under stirring for 48 hours. After completion of the reaction, the solution obtained by adding ethyl acetate to the reaction mixture was washed three times, the organic layer was dried using magnesium sulfate, and then the solvent was distilled off to obtain 9.0 g of liquid crystal aligning polyorganosiloxane (APS-1). . The weight average molecular weight Mw of the obtained polymer was 9,900.

· Precision test

[Example 1]

The polyimide (PI-1) obtained in Synthesis Example 1 was dissolved by mixing 0.5 g and N-methyl-2-pyrrolidone 4.5 g. To this end, it was determined that the polymer precipitated at the stage where the solution became cloudy by visual observation while adding the solvents described in Table 1 below (hereinafter, the second solvents) until the polymers precipitated. In the evaluation of the precipitation resistance test, the case where there was no polymer precipitation was "good", the case where 5 g or more of the second solvent was added, and the precipitation was "possible", and the case where the second solvent was precipitated at less than 5 g was "impossible". As a result, N, N, 2-trimethylpropionamide was "good" for precipitation resistance.

[Examples 2 to 8]

A precipitation resistance test was conducted in the same manner as in Example 1, except that the type of the second solvent to be used was changed as described in Table 1 below. The results are shown in Table 1 below.

Preparation and evaluation of liquid crystal aligning agent

[Example 9A]

<Preparation of liquid crystal aligning agent>

100% by weight of the polyimide (PI-1) obtained in Synthesis Example 1 as the polymer (A), a mixed solvent composed of N, N, 2-trimethylpropionamide (p1) and butyl cellosolve (BC) (solvent composition p1 : BC = 50: 50 (weight ratio), and it was set as the solution of solid content concentration 6.5 weight%. A liquid crystal aligning agent (S-1) was prepared by filtering this solution using a filter having a pore diameter of 1 µm. Moreover, the liquid crystal aligning agent (S-1) is mainly used for manufacture of a vertically-aligned type liquid crystal display element.

<Evaluation of printability 1 (160 ℃)>

About the liquid crystal aligning agent (S-1) prepared above, after filtering with a 1.0 micrometer filter, using the liquid crystal aligning film printing machine (made by Nihon Shashin Inzatsu Co., Ltd.), of the glass substrate with a transparent electrode which consists of an ITO film. It was applied to the transparent electrode surface. Thereafter, the solvent was removed by heating (pre-baking) on a hot plate at 80 ° C. for 1 minute, followed by heating (post-baking) on a hot plate at 160 ° C. for 10 minutes to form a coating film having an average film thickness of 600 MPa and stickiness of the coating film. It was checked for presence or absence. This coating film was observed under a microscope at a magnification of 20 times to check for irregularities in printing and the presence or absence of pinholes. The evaluation was carried out as a case where there was no stickiness, printing irregularity, and pinholes were hardly observed, with good printability (○), stickiness, or when at least one of the printing irregularities and pinholes was observed as a poor printability (x). . As a result, the printability (160 ° C) of the liquid crystal aligning agent was "good".

<Evaluation of printability 2 (220 ℃)>

The liquid crystal aligning agent (S-1) prepared above was evaluated in the same manner as in "Evaluation of Printability 1" above except that the heating temperature during post-baking was changed from 160 ° C to 220 ° C. As a result, the printability (220 ° C) of the liquid crystal aligning agent was "good".

[Examples 10A to 15A and Comparative Example 1A]

The polymer (A) to be used and the type and composition of the solvent were changed as described in Table 2 below, respectively, and the liquid crystal aligning agents (S-2) to (S-7) were carried out in the same manner as in Example 9A above. And (SR-1), respectively. The printability was evaluated in the same manner as in Example 9A above. The results are shown in Table 2 below. In addition, in Table 2, the compounding ratio of the polymer (A) represents the content rate (% by weight) of each polymer with respect to 100% by weight of the total amount of the polymer contained in the liquid crystal aligning agent. In addition, the liquid crystal aligning agents (S-1) to (S-3) are mainly used for the production of vertically aligned liquid crystal display elements, and the liquid crystal aligning agent (S-4) is mainly used for the production of vertically aligned liquid crystal display elements by the photo-alignment method. , Liquid crystal aligning agents (S-5) to (S-6), (SR-1) are mainly for the production of IPS type or FFS type liquid crystal display elements, and the liquid crystal aligning agent (S-7) is mainly for TN type liquid crystal display elements. Each is used for manufacturing.

In addition, the symbol of the solvent composition in Table 2 has the following meaning, respectively.

a: N, N, 2-trimethylpropionamide

b: Butyl cellosolve

c: diacetone alcohol

d: N-methyl-2-pyrrolidone

As shown in Table 2, all of the liquid crystal aligning agents of the examples had good printability at baking temperatures of 160 ° C and 220 ° C. On the other hand, the liquid crystal aligning agent of the comparative example was sticky to the coating film at a baking temperature of 160 ° C, and the printability was poor. From this point, it can be said that the liquid crystal aligning agent of the Example can sufficiently dissolve polyimide, polyamic acid, or the like, and can form a liquid crystal aligning film by heating at a relatively low temperature.

[Examples 16A to 20A]

The polymer (A) to be used and the type and composition of the solvent were changed as described in Table 3 below, respectively, and the liquid crystal aligning agents (S-8) to (S-12) were carried out in the same manner as in Example 9A above. ), Respectively. The printability was evaluated in the same manner as in Example 9A above. Table 3 shows the results. In addition, in Table 3, the compounding ratio of the polymer (A) represents the content rate (% by weight) of each polymer with respect to 100% by weight of the total amount of the polymer contained in the liquid crystal aligning agent. In addition, the liquid crystal aligning agent (S-9) is mainly used for the production of vertically aligned liquid crystal display elements, and the liquid crystal aligning agents (S-8), (S-10), and (S-11) are mainly IPS or FFS type liquid crystal displays. For the manufacture of the elements, the liquid crystal aligning agent (S-12) is mainly used for the production of IPS-type or FFS-type liquid crystal display elements by optical alignment.

In addition, the symbol of the solvent composition in Table 3 has the following meanings, respectively. In addition, the same symbol as Table 2 means the same compound as Table 2.

e: Diethylene glycol diethyl ether

f: diisobutyl ketone

i: γ-butyrolactone

As shown in Table 3, in the liquid crystal aligning agents of Examples 16A to 20A, printability was good at baking temperatures of 160 ° C and 220 ° C.

[Example 9B]

<Preparation of liquid crystal aligning agent>

In the same solvent composition as in Example 9A, a polymer solution was separately prepared to have a solution viscosity of 6 mPa · s, and filtered through a 0.2 μm filter to prepare a liquid crystal aligning agent (S-1a). The liquid crystal aligning agent (S-1a) was provided for evaluation of inkjet coating property.

<Evaluation of surface irregularities of the coating film>

The coating film obtained in the evaluation of printability evaluation 2 (220 ° C) of Example 9A was observed with an atomic force microscope (AFM), and the center average roughness (Ra) was measured. The evaluation was performed when Ra was less than 10 nm with "good" surface irregularities, "possible" when 10 nm or more and less than 15 nm, and "poor" when 15 nm or more. Moreover, in general, when a solvent having good solubility in a polymer is used, the surface tension of the coating film increases, and the leveling property (surface irregularity) of the coating film tends to decrease. On the other hand, it is preferable that a liquid crystal aligning agent has a low surface tension and good solubility to a polymer from a viewpoint of obtaining a favorable film. In this example, the surface unevenness was a result of "good".

<Evaluation of inkjet coating properties>

The glass substrate with a transparent electrode made of ITO was heated on a hot plate at 200 ° C for 1 minute, and then UV / ozone cleaning was performed, and the one immediately after the water contact angle of the transparent electrode surface was 10 ° or less was used as the substrate. The liquid crystal aligning agent (S-1a) prepared above was apply | coated on the transparent electrode surface of the glass substrate with a transparent electrode using an inkjet applicator (made by Shibaura Mechatronics Co., Ltd.). At this time, the application conditions were 2,500 times / (nozzle / minute) and 2 round-trips (4 times in total) with a discharge amount of 250 mg / 10 seconds. After coating, after standing for 1 minute, heating was performed at 80 ° C to form a coated film having an average film thickness of 0.1 µm. For the obtained coating film, when the interference fringe measurement lamp (sodium lamp) was irradiated and observed with the naked eye, the case where both of the stains and the clumps were not visible was set as &quot; good &quot; As a result of evaluating the inkjet coating property as "bad", the inkjet coating property of this liquid crystal aligning agent was "good".

[Examples 10B to 20B and Comparative Example 1B]

The liquid crystal aligning agents (S-2) to (S-12) and (SR-1) were evaluated in the same manner as in Example 9B above to evaluate surface irregularities. The results are shown in Table 4 below.

[Comparative Example 2B]

Except that the solvent to be used is dissolved in a mixed solvent (solvent composition is NMP: PC: BC = 40: 30: 30 (weight ratio)) composed of NMP, propylene carbonate (PC) and butyl cellosolve (BC). A liquid crystal aligning agent (SR-2) was prepared in the same manner as in Example 9A. Moreover, the surface unevenness | corrugation of the coating film was evaluated like Example 9B mentioned above. The results are shown in Table 4 below.

As shown in Table 4, all of the liquid crystal aligning agents of Examples had "good" or "possible" evaluation of surface unevenness. On the other hand, in the comparative example 2B which does not contain the compound (p1) as a solvent component, the surface unevenness | corrugation was evaluation of "poor". From the results of the above experiments, it was found that the liquid crystal aligning agent of the example had both the solubility (precipitation resistance) of the polymer and the leveling property (surface irregularity) of the coating film, and the printability was good even at low-temperature firing. On the other hand, the liquid crystal aligning agent of the comparative example had poor printability at low-temperature baking, or poor leveling property of the coating film.

[Example 21: Retardation film]

(1) Preparation of liquid crystal aligning agent

100 parts by weight of polyamic acid (PA-7) obtained in Synthesis Example 10, mixed solvent consisting of N, N, 2-trimethylpropionamide (DMIB) and butyl cellosolve (BC) (DMIB: BC = 60: 40 (weight ratio) )) To obtain a solution having a solid content concentration of 5% by weight. A liquid crystal aligning agent was prepared by filtering this solution with a filter having a pore size of 0.2 µm.

(2) Preparation of retardation film

The liquid crystal aligning agent prepared above was applied to one surface of the TAC film as a substrate using a bar coater and baked in an oven at 120 ° C for 2 minutes to form a coating film having a film thickness of 100 nm. Subsequently, a polarized ultraviolet ray 500 mJ / cm 2 containing a bright line of 254 nm was irradiated vertically from the substrate normal to the surface of this coating film using an Hg-Xe lamp and a Glen Taylor prism. Subsequently, after filtering the polymerizable liquid crystal (RMS03-013C, manufactured by Merck) with a filter having a pore diameter of 0.2 µm, the polymerizable liquid crystal is coated on a coating film after light irradiation with a bar coater to form a coating film of the polymerizable liquid crystal. did. After baking for 1 minute in an oven adjusted to a temperature of 50 ° C, 1,000 mJ / cm 2 of unpolarized ultraviolet light containing a 365 nm bright line was irradiated from the vertical direction with respect to the coated surface using a Hg-Xe lamp and polymerized. A retardation film was produced by curing the sex liquid crystal to form a liquid crystal layer.

(3) Evaluation of liquid crystal alignment

About the retardation film produced in said (2), liquid crystal orientation (photo-alignment property) was evaluated by observing the presence or absence of an abnormal domain with a naked eye under a cross nicol and a polarization microscope (magnification 2.5 times). For evaluation, the liquid crystal orientation was "good" when the orientation was good with the naked eye and no abnormal domain was observed with a polarization microscope, and the liquid crystal orientation was possible when the abnormal domain was observed with the naked eye while no abnormal domain was observed. , And the case where abnormal domains were observed with the naked eye and a polarization microscope was performed with liquid crystal alignment "bad". As a result, this retardation film was evaluated for liquid crystal alignment "good".

(4) Adhesion

Using the retardation film prepared in the above (2), the adhesion of the coating film formed by the liquid crystal aligning agent to the substrate was evaluated. First, using an equally spaced spacer with a guide, cuts were inserted from the side of the liquid crystal layer side of the retardation film by a cutter knife to form 10 x 10 grid patterns. The depth of each incision was made to reach from the surface of the liquid crystal layer to the middle of the substrate thickness. Subsequently, the cellophane tape was adhered to cover the entire surface of the grid pattern, and then the cellophane tape was peeled off. The cut-out part of the grid pattern after peeling was observed with the naked eye under a cross nicol to evaluate adhesion. In the evaluation, the adhesion was "good" when peeling was not observed at the intersection of the part along the cut line and the grid pattern, and the number of grid eyes where peeling was observed at the section was less than 15% of the total number of grid patterns. The case where the adhesion was "possible" and the number of lattice eyes where peeling was observed on the above part was 15% or more with respect to the total number of lattice patterns was set as the adhesion "bad". As a result, this retardation film was adhesive "good".

Claims (10)

At least one polymer (A) selected from the group consisting of polyamic acid, polyimide, polyamic acid ester and polyorganosiloxane,
It contains the solvent containing the compound (p1) represented by following formula (1),
The liquid crystal aligning agent characterized in that the content of the compound (p1) is 5% by weight to 50% by weight of the total amount of the solvent:

(In the formula (1), R ¹ to R ⁴ are each independently a linear or branched hydrocarbon group having 1 to 6 carbon atoms or a CC bond of the hydrocarbon group, from -O-, -COO- and -OCO- A group having at least one selected). delete According to claim 1,
As the polymer (A), 2,3,5-tricarboxycyclopentyl acetic anhydride, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4,6: 8-2 anhydride , 1,2,3,4-cyclobutanetetracarboxylic acid anhydride, bicyclo [2.2.1] heptane-2,3,5,6-tetracarboxylic acid 2: 3,5: 6-2 anhydride, 1, 3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1 , 3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1, 3-dione, 1,2,4,5-cyclohexanetetracarboxylic acid anhydride and tetracarboxylic acid anhydride containing at least one member selected from the group consisting of pyromellitic acid anhydride and diamine, obtained by reacting A liquid crystal aligning agent containing at least one member selected from the group consisting of polyamic acid, polyimide and polyamic acid ester. The liquid crystal aligning film formed using the liquid crystal aligning agent of Claim 1 or 3. The liquid crystal display element provided with the liquid crystal aligning film of Claim 4. The retardation film provided with the liquid crystal aligning film of Claim 4. The liquid crystal aligning film produced by apply | coating the liquid crystal aligning agent of Claim 1 or 3 to a board | substrate to form a coating film, and irradiating the said coating film with light. The manufacturing method of the liquid crystal aligning film containing the process of forming the coating film by apply | coating the liquid crystal aligning agent of Claim 1 or 3 on a board | substrate, and providing the liquid crystal aligning ability by light irradiation to the said coating film. A step of synthesizing at least one polymer selected from the group consisting of polyamic acid, polyimide and polyamic acid ester in an organic solvent containing a compound (p1) represented by the following formula (1),
It contains the polymer obtained by the said synthesis and the solvent containing the compound (p1) represented by following formula (1), and content of the said compound (p1) is 5 weight% or more and 50 weight% or less of the total amount of the said solvent. A manufacturing method of a liquid crystal aligning agent comprising the step of manufacturing a liquid crystal aligning agent:

(In the formula (1), R ¹ to R ⁴ are each independently a linear or branched hydrocarbon group having 1 to 6 carbon atoms or a CC bond of the hydrocarbon group, from -O-, -COO- and -OCO- A group having at least one selected). The process of forming a coating film by apply | coating the liquid crystal aligning agent of Claim 1 or 3 on a board | substrate,
A step of irradiating light to the coating film,
Method for producing a retardation film comprising a step of applying a polymerizable liquid crystal on the coating film after the light irradiation and curing.