WO2020045549A1

WO2020045549A1 - Liquid crystal aligning agent, liquid crystal alignment film and liquid crystal display element

Info

Publication number: WO2020045549A1
Application number: PCT/JP2019/033838
Authority: WO
Inventors: 祐太飯塚; 功一朗別府; 加名子鈴木; 耕平後藤
Original assignee: 日産化学株式会社
Priority date: 2018-08-30
Filing date: 2019-08-29
Publication date: 2020-03-05
Also published as: KR20210047864A; JP7371634B2; CN112639595A; JPWO2020045549A1; TW202030253A

Abstract

The present invention provides: a liquid crystal alignment film which is suppressed in changes of pretilt angles even after long-time driving, thereby exhibiting excellent display reliability, and which has high voltage holding characteristics, while being capable of reducing the charge accumulation; a liquid crystal display element which comprises this liquid crystal alignment film; and a liquid crystal aligning agent which enables the achievement of this liquid crystal alignment film. The present invention provides a liquid crystal aligning agent which contains a polymer that has a photo-alignment group represented by formula (pa-1) and a thermally crosslinkable group A (component (A)), a polymer that is selected from among polyimides and precursors thereof (component (B)) and a solvent, and which satisfies at least one of the following conditions Z1 and Z2. Z1: The polymer serving as the component (A) additionally has a thermally crosslinkable group B. Z2: A compound having two or more thermally crosslinkable groups B in each molecule is additionally contained as a component (C). (In formula (pa-1), A represents a phenylene or the like; R₁ represents a single bond, an oxygen atom or the like; R₂ represents a divalent aromatic group or the like; R₃ represents a single bond, an oxygen atom or the like; R₄ represents a linear or branched alkyl group having 1-40 carbon atoms or a monovalent organic group having 3-40 carbon atoms, which includes an alicyclic group; D represents an oxygen atom, a sulfur atom or -NR_d-; a represents an integer of 0-3; and * represents a bonding position. The thermally crosslinkable group A and the thermally crosslinkable group B are selected so that the thermally crosslinkable group A and the thermally crosslinkable group B are crosslinkingly reacted with each other by means of heat.)

Description

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

(4) The present invention relates to a liquid crystal alignment agent, a liquid crystal alignment film obtained by using the same, and a liquid crystal display device including the obtained liquid crystal alignment film. More specifically, the present invention relates to a liquid crystal alignment agent capable of providing a liquid crystal alignment film having good liquid crystal alignment properties, excellent pretilt angle developing ability, and high reliability, and a liquid crystal display element having excellent display quality.

In a liquid crystal display device, a liquid crystal alignment film plays a role of aligning liquid crystal in a certain direction. At present, the main liquid crystal alignment film used industrially is a polyimide precursor polyamic acid (also referred to as polyamic acid), a polyamic acid ester, or a polyimide-based liquid crystal alignment agent made of a polyimide solution. It is produced by coating and forming a film.
In the case where the liquid crystal is aligned parallel or inclined with respect to the substrate surface, a surface stretching process by rubbing is further performed after the film is formed.

On the other hand, when the liquid crystal is vertically aligned with respect to the substrate (referred to as a vertical alignment (VA) method), a long-chain alkyl, a cyclic group or a combination of a cyclic group and an alkyl group (for example, see Patent Document 1), a steroid skeleton ( For example, a liquid crystal alignment film in which a hydrophobic group is introduced into a side chain of polyimide, such as that described in Patent Document 2, is used. In this case, when a voltage is applied between the substrates to tilt the liquid crystal molecules in a direction parallel to the substrate, the liquid crystal molecules need to be tilted from the normal direction of the substrate to one direction in the substrate plane. . As means for this, for example, a method of providing a projection on the substrate, a method of providing a slit in the display electrode, or rubbing the liquid crystal molecules slightly in one direction in the substrate plane from the normal direction of the substrate ( Pretilt), and further adding a photopolymerizable compound to the liquid crystal composition in advance and using it together with a vertical alignment film of polyimide or the like, and irradiating ultraviolet rays while applying a voltage to the liquid crystal cell to pretilt the liquid crystal. A method (for example, see Patent Document 3) has been proposed.

In recent years, a method (photo-alignment method) utilizing an anisotropic photochemical reaction by irradiation with polarized ultraviolet rays or the like has been proposed as an alternative to the formation of projections and slits in VA-mode liquid crystal alignment control and PSA technology. That is, it is known that the tilt direction of liquid crystal molecules when voltage is applied can be uniformly controlled by irradiating polarized ultraviolet light to a vertically reactive polyimide film having photoreactivity to impart alignment regulating ability and pretilt angle developing ability. (See Patent Document 4).

VA liquid crystal display elements are used in TVs and on-vehicle displays because of their features such as high contrast and wide viewing angle. A liquid crystal display device for TV uses a backlight that generates a large amount of heat in order to obtain high brightness, and a liquid crystal display device used in an in-vehicle application, for example, a car navigation system or a meter panel, is used under a high temperature environment for a long time. May be used or neglected. If the pretilt angle changes gradually under such severe conditions, problems such as the inability to obtain initial display characteristics and the occurrence of uneven display may occur. In addition, when the liquid crystal is driven, the voltage holding characteristics and the charge storage characteristics are also affected by the liquid crystal alignment film. When the voltage holding ratio is low, the contrast of the display screen decreases. When the charge storage with respect to the DC voltage is large. Causes a phenomenon that the display screen is burned.

JP-A-3-179323 JP-A-4-281427 Japanese Patent No. 4504626 Japanese Patent No. 4995267

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and its problem is that the change in pretilt angle is small even after long-time driving, the display reliability is excellent, the voltage holding characteristics are high, and the charge accumulation is reduced. An object of the present invention is to provide a liquid crystal alignment film that can be used, a liquid crystal display device having the same, and a liquid crystal alignment agent that provides the same.

The present inventors have found the invention having the following <X>.
<X> A polymer having a photo-alignable group represented by the following formula (pa-1) and a thermally crosslinkable group A as the component (A), and a polymer selected from polyimide and its precursor as the component (B) Having at least one group selected from a vertical alignment group and a tertiary butoxycarbonyl group or containing a polymer and a solvent which are at least one of chemically imidized, and the following requirements Z1 and A liquid crystal aligning agent satisfying at least one of Z2:
Z1: The polymer as the component (A) further has a thermally crosslinkable group B.
Z2: As a component (C), a compound having two or more thermally crosslinkable groups B in the molecule is further contained.

In the formula, A is optionally a group selected from fluorine, chlorine and cyano, or an alkoxy group having 1 to 5 carbon atoms, a linear or branched alkyl residue (optionally, Pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-thiophenylene, 2,5-furanylene substituted with a cyano group or one or more halogen atoms), Represents 1,4- or 2,6-naphthylene or phenylene, R ₁ is a single bond, an oxygen atom, —COO— or —OCO—, and R ₂ is a divalent aromatic group, a divalent alicyclic A divalent heterocyclic group or a divalent fused cyclic group, R ₃ is a single bond, an oxygen atom, —COO— or —OCO—, and R ₄ is a linear group having 1 to 40 carbon atoms. Or 3 to 4 carbon atoms including a branched alkyl group or an alicyclic group 0 is a monovalent organic group, D represents an oxygen atom, a sulfur atom or —NR _d — (where R _d represents a hydrogen atom or an alkyl having 1 to 3 carbon atoms); Is an integer of 1 to 3, and * represents a bonding position.
The thermally crosslinkable group A and the thermally crosslinkable group B are each independently a carboxyl group, an amino group, an alkoxymethylamide group, a hydroxymethylamide group, a hydroxyl group, an epoxy site-containing group, an oxetanyl group, a thiiranyl group, an isocyanate group and a block. An organic group selected from the group consisting of isocyanate groups, wherein the heat-crosslinkable group A and the heat-crosslinkable group B are selected so as to cause a cross-linking reaction by heat; The groups B may be the same as one another.

According to the present invention, the liquid crystal alignment is good, the pretilt angle developing ability is excellent, the change in the pretilt angle after driving for a long time is small, the display reliability is excellent, the voltage holding characteristic is high, and the charge accumulation is improved. A liquid crystal alignment film and a liquid crystal alignment agent that can be reduced can be provided.
Further, the liquid crystal display device manufactured by the method of the present invention has excellent display characteristics.

The liquid crystal aligning agent of the present invention is a polymer having a photo-alignable group represented by the following formula (pa-1) and a thermally crosslinkable group A as a component (A), and a polyimide and a precursor thereof as a component (B) A polymer selected from polyimide and a precursor thereof, having at least one group selected from a vertical alignment group and a tertiary butoxycarbonyl group, or being chemically imidized. A liquid crystal aligning agent containing at least one of a polymer and a solvent and satisfying at least one of the following requirements Z1 and Z2:
Z1: The polymer as the component (A) further has a thermally crosslinkable group B.
Z2: As a component (C), a compound having two or more thermally crosslinkable groups B in the molecule is further contained.

Here, "two or more in a molecule" means, for example, a case where two or more same types of groups are contained in a molecule, for example, two or more epoxy groups, or a combination of an epoxy group and a thiirane group. In addition, the meaning includes the case where a total of two or more different groups are contained in the molecule. “Two or more in the molecule” preferably contains two or more groups of the same type in the molecule.

The polymer as the component (A) contained in the liquid crystal aligning agent of the present invention has high sensitivity to light, and thus can exhibit alignment control ability even when irradiated with polarized ultraviolet rays with a low exposure.
In addition, when the polymer as the component (A) contains the heat crosslinkable group A and further contains the heat crosslinkable group B in the component, the component (A) can be used even when the firing time of the liquid crystal aligning agent is short. The cross-linking reaction containing the polymer which is is possible. Thereby, when the photo-alignment site develops anisotropy by a photoreaction, the anisotropy tends to remain (memory) in the liquid crystal alignment film, so that the liquid crystal alignment is enhanced and the pretilt angle of the liquid crystal is expressed. It is possible to do.

液晶 Further, the liquid crystal alignment agent of the present invention contains a polymer as the component (B), so that it is possible to improve electric characteristics such as improvement in voltage holding ratio and suppression of residual charge accumulation.

The photo-alignable group, the thermally crosslinkable group A, and the thermally crosslinkable group B represented by the above formula (pa-1) can all be side chains in the polymer. Thus, it can be paraphrased as “side chain”.
Hereinafter, each component of the present invention will be described in detail.

<(A) component: specific polymer>
[Photo-Alignment Group Represented by Formula (pa-1)]
In the present invention, the site having photo-alignment represented by the above formula (pa-1) in the molecule can be represented by the following formula (a-1), for example. In addition, the site may include, but is not limited to, a structure derived from a monomer represented by the following formula (a-1-m). In the formula, Ia is a monovalent organic group represented by the following formula (pa-1).

In the formula (pa-1), A is optionally a group selected from fluorine, chlorine, cyano, or an alkoxy group having 1 to 5 carbon atoms, a linear or branched alkyl residue (which is Pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-thiophenylene, optionally substituted with one cyano group or one or more halogen atoms), , 5-furanylene, 1,4- or 2,6-naphthylene or phenylene, R ₁ is a single bond, an oxygen atom, —COO— or —OCO—, and R ₂ is a divalent aromatic group, valent alicyclic group, a divalent heterocyclic group, or a divalent condensed cyclic group, _{R 3} is a single bond, an oxygen atom, a -COO- or -OCO-, _{R 4} is C 1 -C Contains up to 40 linear or branched alkyl or alicyclic groups A monovalent organic group having 3 to 40 carbon atoms, wherein D represents an oxygen atom, a sulfur atom or -NR _d- (where R _d represents a hydrogen atom or an alkyl having 1 to 3 carbon atoms) , a is an integer of 0-3, * represents a bonding position to _{S a.}

Bond in the formula (a-1) or (a-1-m), S a represents a spacer unit, linking groups of the left S _a is the main chain of the specific polymer, optionally via a spacer To do so.
S _a can be represented for example by the structure of the following formula (Sp).

In the formula (Sp),
Binding of the left of the W ₁ represents a bond to _{M b,}
The bond to the right of W ₃ represents a bond to _Ia ;
W ₁ , W ₂ and W ₃ each independently represent a single bond, a divalent heterocyclic ring, — (CH ₂ ) _n — (where n represents 1 to 20), —OCH ₂ —, and — Represents CH ₂ O—, —COO—, —OCO—, —CH ＝ CH—, —CF ＝ CF—, —CF ₂ O—, —OCF ₂ —, —CF ₂ CF ₂ —, or —C≡C—. But one or more of the non-adjacent CH ₂ groups in these substituents are independently —O—, —CO—, —CO—O—, —O—CO—, —Si (CH ₃ ) ₂ — O-Si (CH ₃ ) _2- , -NR-, -NR-CO-, -CO-NR-, -NR-CO-O-, -OCO-NR-, -NR-CO-NR-, -CH = CH-, -C≡C- or -O-CO-O- (wherein R independently represents hydrogen or a linear or branched alkyl group having 1 to 5 carbon atoms) Rukoto can,
A ₁ and A ₂ each independently represent a single bond, a divalent alkyl group, a divalent aromatic group, a divalent alicyclic group, or a divalent heterocyclic group. Each of the groups may be unsubstituted or one or more hydrogen atoms may be substituted by a fluorine atom, a chlorine atom, a cyano group, a methyl group or a methoxy group.

In the formula (a-1-m), Ma represents _a polymerizable group. Examples of the polymerizable group include (meth) acrylate, fumarate, maleate, α-methylene-γ-butyrolactone, styrene, vinyl, maleimide, norbornene, radical polymerizable groups of (meth) acrylamide and derivatives thereof, and siloxane. it can. Preferably, (meth) acrylate, α-methylene-γ-butyrolactone, styrene, vinyl, maleimide, and acrylamide are used.
r is an integer satisfying 1 ≦ r ≦ 3.
M _b is selected from a single bond, a (r + 1) -valent heterocyclic ring, a linear or branched alkyl group having 1 to 10 carbon atoms, a (r + 1) -valent aromatic group, and a (r + 1) -valent alicyclic group. Wherein each group is unsubstituted or one or more hydrogen atoms may be substituted by a fluorine atom, a chlorine atom, a cyano group, a methyl group or a methoxy group.

The aromatic group of A _{1, A} _2, and M _b, for example, benzene, biphenyl, an aromatic hydrocarbon having 6 to 18 carbon atoms such as naphthalene. The alicyclic group of A _{1, A} _2, and M _b, can be mentioned such as cyclohexane, an alicyclic hydrocarbon having 6 to 12 carbon atoms such as bicyclohexane. The heterocyclic ring in A _{1, A} _2, and M _b, may include, for example, pyridine, piperidine, nitrogen-containing heterocyclic ring piperazine. Examples of the alkyl group for A ₁ and A ₂ include a linear or branched alkyl group having 1 to 10 carbon atoms.

From the viewpoint of exhibiting good vertical alignment control ability and a stable pretilt angle, the group represented by the above (pa-1) is preferably a group represented by the following (pa-1-a). In addition, the site may include, but is not limited to, a structure derived from a monomer represented by the following formula (pa-1-ma).

In the formula (pa-1-a) or (pa-1-ma), M _a , M _b , and _Sa have the same definitions as described above.
Z is an oxygen atom or a sulfur atom.
X _a and X _b are each independently a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group or an alkyl group having 1 to 3 carbon atoms.
R ₁ is a single bond, an oxygen atom, —COO— or —OCO—.
R ₂ is a divalent aromatic group, a divalent alicyclic group, or a divalent heterocyclic group.
R ₃ is a single bond, an oxygen atom, —COO— or —OCO—.
R ₄ is a monovalent organic group having 3 to 40 carbon atoms including a linear or branched alkyl group having 1 to 40 carbon atoms or an alicyclic group.
R ₅ is an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a fluorine atom or a cyano group, preferably a methyl group, a methoxy group or a fluorine atom.
a is an integer of 0 to 3, and b is an integer of 0 to 4.

Wherein (pa-1-a) or (pa-1-ma), as a straight-chain or branched-chain alkylene group having 1 to 10 carbon atoms _{S a,} linear or branched alkylenes having 1 to 8 carbon atoms Group, for example, methylene group, ethylene group, n-propylene group, n-butylene group, t-butylene group, n-pentylene group, n-hexylene group, n-heptylene group, and n-octylene group are preferable. .
As the divalent aromatic group of S _a, for example, 1,4-phenylene group, 2-fluoro-1,4-phenylene group, 3-fluoro-1,4-phenylene group, 2,3,5,6 A fluoro-1,4-phenylene group and the like can be mentioned.

In the formula (pa-1-a) or (pa-1-ma), as _a divalent alicyclic group of Sa, for example, trans-1,4-cyclohexylene, trans-trans-1,4-bicyclohexyl Silen etc. can be mentioned.
Given as the divalent heterocyclic group S _a, for example, 1,4-pyridylene, 2,5-pyridylene group, 1,4-furanylene group, 1,4-piperazine, 1,4-piperidine group be able to.
S _a is preferably an alkylene group having 1 to 8 carbon atoms, more preferably an alkylene group having 1 to 6 carbon atoms, more preferably may be from an alkylene group having 1 to 4 carbon atoms.

Examples of the divalent aromatic group for R ₂ include 1,4-phenylene group, 2-fluoro-1,4-phenylene group, 3-fluoro-1,4-phenylene group, 2,3,5,6-tetra Examples thereof include a fluoro-1,4-phenylene group and a naphthylene group.
Examples of the divalent alicyclic group for R ₂ include trans 1,4-cyclohexylene, trans-trans-1,4-bicyclohexylene, and the like.
Examples of the divalent heterocyclic group for R ₂ include 1,4-pyridylene, 2,5-pyridylene, 1,4-furanylene, 1,4-piperazine, and 1,4-piperidine. be able to.
R ₂ is preferably a 1,4-phenylene group, trans 1,4-cyclohexylene, trans-trans-1,4-bicyclohexylene.

Examples of the linear or branched alkyl group having 1 to 40 carbon atoms for R ₄ include a linear or branched alkyl group having 1 to 20 carbon atoms, and a part of hydrogen atoms of the alkyl group. Or all may be substituted by a fluorine atom. Examples of such alkyl groups include, for example, methyl, ethyl, n-propyl, n-butyl, t-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-octyl -Nonyl group, n-decyl group, n-lauryl 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, 4,4,4-trifluorobutyl group, 4,4,5,5,5-pentafluoropentyl, 4,4,5,5,6,6,6-heptafluoro Hexyl group, 3,3,4,4,5,5,5-heptafluoropentyl group, 2,2,2-trifluoroethyl group, 2,2,3,3,3-pentafluoropropyl group, 2- (Perfluorobutyl) Methyl group, 2- (perfluorooctyl) ethyl group and a 2- (perfluorodecyl) ethyl group or the like.

Examples of the monovalent organic group having 3 to 40 carbon atoms including an alicyclic group represented by R ₄ include a cholesteryl group, a cholestanyl group, an adamantyl group, the following formula (Alc-1) or (Alc-2) (wherein R ₇ is a hydrogen atom, a fluorine atom or an alkyl group having 1 to 20 carbon atoms, and the alkyl group having 1 to 20 carbon atoms may be substituted with a fluorine atom, and * indicates a bonding position. Examples include the groups represented.

モノマー As the monomer represented by the formula (pa-1-ma), the structures represented by the formulas (paa-1-ma1) to (paa-1-ma18) can be exemplified, but are not limited thereto. In the formula, “E” indicates that the compound is E-form, and “t” indicates that the cyclohexyl group is trans.

[Thermal crosslinkable group A and thermal crosslinkable group B]
The thermally crosslinkable group A and the thermally crosslinkable group B are each independently a carboxyl group, an amino group, an alkoxymethylamide group, a hydroxymethylamide group, a hydroxyl group, an epoxy site-containing group, an oxetanyl group, a thiiranyl group, an isocyanate group and a block. An organic group selected from the group consisting of isocyanate groups, wherein the heat-crosslinkable group A and the heat-crosslinkable group B are selected so as to cause a cross-linking reaction by heat; The groups B may be the same as one another.

As a combination of such a heat-crosslinkable group A and a heat-crosslinkable group B, one is a carboxyl group, the other is an epoxy group, an oxetanyl group or a thiiranyl group, one is a hydroxy group, and the other is a hydroxy group. Is a blocked isocyanate group, one is a phenolic hydroxy group, the other is an epoxy group, an oxetanyl group or a thiiranyl group, one is a carboxyl group, the other is a blocked isocyanate group, and one is an amino group. And the other is a blocked isocyanate group, or both are N-alkoxymethylamides. More preferred combinations include a carboxyl group and an epoxy group, and a hydroxy group and a blocked isocyanate group.

In order to introduce such a thermally crosslinkable group A into the polymer as the component (A), a monomer having the thermally crosslinkable group A may be copolymerized.

When the liquid crystal aligning agent of the present invention satisfies the requirement Z1, when producing the polymer as the component (A), both the monomer having the thermocrosslinkable group A and the monomer having the thermocrosslinkable group B are used. What is necessary is just to copolymerize.

Examples of the monomer having a thermocrosslinkable group include, for example,
Acrylic acid, methacrylic acid, crotonic acid, mono- (2- (acryloyloxy) ethyl) phthalate, mono- (2- (methacryloyloxy) ethyl) phthalate, N- (carboxyphenyl) maleimide, N- (carboxyphenyl) methacryl Amides and monomers having a carboxyl group such as N- (carboxyphenyl) acrylamide;

2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl acrylate, 4-hydroxybutyl methacrylate, 2,3-dihydroxypropyl acrylate, 2,3-dihydroxypropyl Methacrylate, diethylene glycol monoacrylate, diethylene glycol monomethacrylate, caprolactone 2- (acryloyloxy) ethyl ester, caprolactone 2- (methacryloyloxy) ethyl ester, poly (ethylene glycol) ethyl ether acrylate, poly (ethylene glycol) ethyl ether methacrylate, 5- Acryloyloxy-6-hydroxynorbornene-2-carbo Monomers having Shirikku 6 lactone, and 5- methacryloyloxy-6-hydroxy-norbornene-2-carboxylic-6-hydroxy groups of the lactone and the like;

{Monomers having a phenolic hydroxy group such as hydroxystyrene, N- (hydroxyphenyl) methacrylamide, N- (hydroxyphenyl) acrylamide, N- (hydroxyphenyl) maleimide, and N- (hydroxyphenyl) maleimide;

{Monomers having an amino group such as aminoethyl acrylate, aminoethyl methacrylate, aminopropyl acrylate, and aminopropyl methacrylate;

Substituted with a hydroxymethyl group or an alkoxymethyl group such as N-hydroxymethyl (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-ethoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, etc. ) Acrylamide compounds;

Allyl glycidyl ether, glycidyl acrylate, glycidyl methacrylate, 2-methyl glycidyl methacrylate, glycidyl α-ethyl acrylate, glycidyl α-n-propyl acrylate, glycidyl acrylate α-n-butyl, 3,4-acrylate Epoxybutyl, 3,4-epoxybutyl methacrylate, 6,7-epoxyheptyl acrylate, 6,7-epoxyheptyl methacrylate, 6,7-epoxyheptyl α-ethylacrylate, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl ether, 3,4-epoxycyclohexylmethyl methacrylate, 3-ethenyl-7-oxabicyclo [4.1.0] heptane, 1,2-epoxy-5 Hexene, 1,7-o Monomers having an epoxy site-containing group, such as data diene monoepoxide;

3- (acryloyloxymethyl) oxetane, 3- (acryloyloxymethyl) -2-methyloxetane, 3- (acryloyloxymethyl) -3-ethyloxetane, 3- (acryloyloxymethyl) -2-trifluoromethyloxetane, 3- (acryloyloxymethyl) -2-pentafluoroethyloxetane, 3- (acryloyloxymethyl) -2-phenyloxetane, 3- (acryloyloxymethyl) -2,2-difluorooxetane, 3- (acryloyloxymethyl) -2,2,4-trifluorooxetane, 3- (acryloyloxymethyl) -2,2,4,4-tetrafluorooxetane, 3- (2-acryloyloxyethyl) oxetane, 3- (2-acryloyloxyethyl ) -2-Ethyloxe 3- (2-acryloyloxyethyl) -3-ethyloxetane, 3- (2-acryloyloxyethyl) -2-trifluoromethyloxetane, 3- (2-acryloyloxyethyl) -2-pentafluoroethyloxetane 3- (2-acryloyloxyethyl) -2-phenyloxetane, 3- (2-acryloyloxyethyl) -2,2-difluorooxetane, 3- (2-acryloyloxyethyl) -2,2,4-tri Acrylic acid esters such as fluorooxetane and 3- (2-acryloyloxyethyl) -2,2,4,4-tetrafluorooxetane; 3- (methacryloyloxymethyl) oxetane, 3- (methacryloyloxymethyl) -2-methyl Oxetane, 3- (methacryloyloxymethyl) -3-ethyl Oxetane, 3- (methacryloyloxymethyl) -2-trifluoromethyloxetane, 3- (methacryloyloxymethyl) -2-pentafluoroethyloxetane, 3- (methacryloyloxymethyl) -2-phenyloxetane, 3- (methacryloyloxy Methyl) -2,2-difluorooxetane, 3- (methacryloyloxymethyl) -2,2,4-trifluorooxetane, 3- (methacryloyloxymethyl) -2,2,4,4-tetrafluorooxetane, 3- (2-methacryloyloxyethyl) oxetane, 3- (2-methacryloyloxyethyl) -2-ethyloxetane, 3- (2-methacryloyloxyethyl) -3-ethyloxetane, 3- (2-methacryloyloxyethyl) -2 -Trifluoromethyl Oxetane, 3- (2-methacryloyloxyethyl) -2-pentafluoroethyloxetane, 3- (2-methacryloyloxyethyl) -2-phenyloxetane, 3- (2-methacryloyloxyethyl) -2,2-difluorooxetane Monomers having an oxetanyl group such as, 3- (2-methacryloyloxyethyl) -2,2,4-trifluorooxetane and 3- (2-methacryloyloxyethyl) -2,2,4,4-tetrafluorooxetane;

2,3-epithiopropyl acrylate or methacrylate, and 2- or 3- or 4- (β-epithiopropylthiomethyl) styrene, 2- or 3- or 4- (β-epithiopropyloxymethyl) styrene, A monomer having a thiiranyl group such as 2- or 3- or 4- (β-epithiopropylthio) styrene, 2- or 3- or 4- (β-epithiopropyloxy) styrene;

2- (0- (1′-methylpropylideneamino) carboxyamino) ethyl acrylate, 2- (3,5-dimethylpyrazolyl) carbonylamino) ethyl acrylate, 2- (0- (1′-methyl) methacrylate Monomers having a blocked isocyanate group, such as propylideneamino) carboxyamino) ethyl and 2- (3,5-dimethylpyrazolyl) carbonylamino) ethyl methacrylate; In addition, (meth) acrylamide means both acrylamide and methacrylamide.

In the present invention, when the specific copolymer is obtained, the monomer having the photo-alignment group represented by the above formula (a-1-m) and the heat-crosslinkable group A and, if necessary, the heat-crosslinkable group A In addition to the monomer having the group B, other monomers copolymerizable with these monomers can be used in combination.

Specific examples of such other monomers include acrylate compounds, methacrylate compounds, maleimide compounds, acrylonitrile, maleic anhydride, styrene compounds, vinyl compounds, N-methoxymethyl (meth) acrylamide, N-butoxymethyl Examples thereof include acrylamide compounds such as (meth) acrylamide and acrylamide, and monomers having a nitrogen-containing aromatic heterocyclic group and a polymerizable group.

Examples of the acrylate compound include methyl acrylate, ethyl acrylate, isopropyl acrylate, benzyl acrylate, naphthyl acrylate, anthryl acrylate, anthryl methyl acrylate, phenyl acrylate, 2,2,2-trifluoroethyl acrylate, and tert-butyl. Acrylate, cyclohexyl acrylate, isobornyl acrylate, 2-methoxyethyl acrylate, methoxytriethylene glycol acrylate, 2-ethoxyethyl acrylate, tetrahydrofurfuryl acrylate, 3-methoxybutyl acrylate, 2-methyl-2-adamantyl acrylate, 2- Propyl-2-adamantyl acrylate, 8-methyl-8-tricyclodecyl acrylate, Beauty, etc. 8-ethyl-8-tricyclodecyl acrylate.

Examples of the methacrylate compound include, for example, methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, hexadecyl methacrylate, octadecyl methacrylate, benzyl methacrylate, naphthyl methacrylate, anthryl methacrylate, anthryl methyl methacrylate, phenyl methacrylate, 2,2,2-triacrylate Fluoroethyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, 2-methoxyethyl methacrylate, methoxytriethylene glycol methacrylate, 2-ethoxyethyl methacrylate, tetrahydrofurfuryl methacrylate, 3-methoxybutyl methacrylate, 2-methyl- 2-adamantyl methacrylate , 2-propyl-2-adamantyl methacrylate, 8-methyl-8-tricyclodecyl methacrylate, and, 8-ethyl-8-tricyclodecyl methacrylate.

Examples of the (meth) acrylamide compound include acrylamide, methacrylamide, N-methylacrylamide, N, N-dimethylacrylamide, and N, N-diethylacrylamide.

{Examples of the vinyl compound include methyl vinyl ether, benzyl vinyl ether, vinyl naphthalene, vinyl carbazole, allyl glycidyl ether, and 3-ethenyl-7-oxabicyclo [4.1.0] heptane.

Examples of the styrene compound include styrene, methylstyrene, chlorostyrene, and bromostyrene.

Examples of the maleimide compound include maleimide, N-methylmaleimide, N-phenylmaleimide, N-cyclohexylmaleimide, and the like.

The nitrogen-containing aromatic heterocycle is a structure selected from the group consisting of the following formulas [Na] to [Nb] (wherein Z ₂ is a linear or branched alkyl group having 1 to 5 carbon atoms). Is preferably an aromatic cyclic hydrocarbon containing at least one, and preferably from 1 to 4.

Specifically, oxazole ring, thiazole ring, pyridine ring, pyrimidine ring, quinoline ring, 1-pyrazoline ring, isoquinoline ring, thiadiazole ring, pyridazine ring, triazine ring, pyrazine ring, phenanthroline ring, quinoxaline ring, benzothiazole ring, Oxadiazole ring, acridine ring and the like can be mentioned. Further, the carbon atom of the nitrogen-containing aromatic heterocyclic ring may have a substituent containing a hetero atom. Among these, for example, a pyridine ring is exemplified.

Examples of the monomer having a nitrogen-containing aromatic heterocyclic group and a polymerizable group include 2- (2-pyridylcarbonyloxy) ethyl (meth) acrylate, 2- (3-pyridylcarbonyloxy) ethyl (meth) acrylate, -(4-pyridylcarbonyloxy) ethyl (meth) acrylate, and the like.

その他 The other monomers used in the present invention may be used alone or in a combination of two or more.

The photoreactive site represented by the above formula (pa-1) to be contained in the polymer as the component (A) of the liquid crystal alignment agent of the present invention may be used alone or in combination of two or more. May be used in combination.

The photoreactive site represented by the above formula (pa-1) contains 5 to 95 mol%, 10 to 60 mol%, or 15 to 50 mol% of all the repeating units of the polymer as the component (A). Is preferably performed.

The site having a heat-crosslinkable group to be contained in the polymer of the present invention may use the heat-crosslinkable group A alone, or a combination of two or more sites including the heat-crosslinkable group A and the heat-crosslinkable group B. May be used.
The introduced amount of the site having a heat crosslinkable group is preferably 5 to 95 mol%, 40 to 90 mol%, or 50 to 85 mol% of all the repeating units of the polymer as the component (A).

The content of the structure derived from the other monomer is preferably 0 to 40 mol%, 0 to 30 mol%, or 0 to 20 mol% of all the repeating units of the polymer as the component (A).

<Method for producing specific polymer>
The specific polymer of the component (A) contained in the liquid crystal aligning agent of the present invention includes a monomer having a photo-alignable group represented by the above formula (pa-1) and a monomer having the above-described thermally crosslinkable group A And, if desired, by copolymerizing the above-mentioned monomer having a thermally crosslinkable group B. Further, it can be copolymerized with the above other monomers.

The method for producing the specific polymer of the component (A) in the present invention is not particularly limited, and a general-purpose method used industrially can be used. Specifically, it can be produced by cationic polymerization, radical polymerization, or anionic polymerization utilizing a vinyl group of a monomer. Among these, radical polymerization is particularly preferred from the viewpoint of easy reaction control.
As the polymerization initiator for radical polymerization, known compounds such as a radical polymerization initiator and a reversible addition-cleavage chain transfer (RAFT) polymerization reagent can be used.

The radical thermal polymerization initiator is a compound that generates a radical when heated to a temperature higher than the decomposition temperature. Examples of such a radical thermal polymerization initiator include ketone peroxides (eg, methyl ethyl ketone peroxide, cyclohexanone peroxide), diacyl peroxides (eg, acetyl peroxide, benzoyl peroxide), and hydroperoxides (eg, peroxides). Hydrogen, tert-butylhydroxide, cumene hydroperoxide, etc.), dialkyl peroxides (di-tert-butyl peroxide, dicumyl peroxide, dilauroyl peroxide, etc.), peroxyketals (dibutylperoxycyclohexane) Etc.), alkyl peresters (peroxyneodecanoic acid-tert-butyl ester, peroxypivalic acid-tert-butyl ester, peroxy-2-ethylcyclohexa) Acid-tert-amyl ester, etc.), persulfates (potassium persulfate, sodium persulfate, ammonium persulfate, etc.), azo compounds (azobisisobutyronitrile, and 2,2′-di (2-hydroxyethyl)) Azobisisobutyronitrile).

ラジカル Such radical thermal polymerization initiators can be used alone or in combination of two or more.

The radical photopolymerization initiator is not particularly limited as long as it is a compound that initiates radical polymerization by light irradiation. Examples of such a radical photopolymerization initiator include known compounds such as benzophenone, Michler's ketone, 4,4′-bis (diethylamino) benzophenone, xanthone, thioxanthone, and isopropylxanthone. These compounds may be used alone or in combination of two or more.
The radical polymerization method is not particularly limited, and an emulsion polymerization method, a suspension polymerization method, a dispersion polymerization method, a precipitation polymerization method, a bulk polymerization method, a solution polymerization method, or the like can be used.

The solvent used for the polymerization reaction of the specific polymer as the component (A) is not particularly limited as long as the produced polymer can be dissolved. Specific examples include solvents described in the section of <Solvent> below, for example, N-alkyl-2-pyrrolidones, dialkylimidazolidinones, lactones, carbonates, ketones, and compounds represented by the formula (Sv-1). And a compound represented by the formula (Sv-2), tetrahydrofuran, 1,4-dioxane, dimethyl sulfone, dimethyl sulfoxide, and the like.
These solvents may be used alone or as a mixture. Further, even if the solvent does not dissolve the produced polymer, it may be mixed with the above-mentioned solvent and used as long as the produced polymer does not precipitate.
Further, since oxygen in the solvent causes inhibition of the polymerization reaction in radical polymerization, it is preferable to use an organic solvent which has been degassed to the extent possible.

The polymerization temperature at the time of radical polymerization can be selected from any temperature of 30 to 150 ° C., but is preferably in the range of 50 to 100 ° C. The reaction can be carried out at any concentration, but the monomer concentration is preferably 1 to 50% by mass, more preferably 5 to 30% by mass. The initial stage of the reaction is carried out at a high concentration, after which an organic solvent can be added.
In the above-described radical polymerization reaction, when the ratio of the radical polymerization initiator to the monomer is large, the molecular weight of the obtained polymer is small, and when the ratio is small, the molecular weight of the obtained polymer is large. It is preferably 0.1 to 10 mol% based on the monomer to be polymerized. At the time of polymerization, various monomer components, a solvent, an initiator and the like can be added.

[Recovery of polymer]
When recovering the produced polymer from the reaction solution obtained by the above reaction, the reaction solution may be put into a poor solvent to precipitate the polymer. Examples of the poor solvent used for precipitation include methanol, acetone, hexane, heptane, butyl cellosolve, heptane, ethanol, toluene, benzene, diethyl ether, methyl ethyl ether, water and the like. The polymer that has been put into a poor solvent and precipitated can be collected by filtration and then dried at normal temperature or reduced pressure at normal temperature or by heating. Further, by repeating the operation of re-dissolving the polymer recovered by precipitation in an organic solvent and recovering and recovering the precipitate two to ten times, impurities in the polymer can be reduced. In this case, examples of the poor solvent include alcohols, ketones, and hydrocarbons. It is preferable to use three or more kinds of poor solvents selected from these, because the purification efficiency is further increased.

The molecular weight of the specific polymer of the component (A) is determined by a GPC (Gel Permeation Chromatography) method in consideration of the strength of the obtained coating film, the workability in forming the coating film, and the uniformity of the coating film. The molecular weight is preferably from 2,000 to 1,000,000, more preferably from 5,000 to 100,000.

<(B) component>
The component (B) contained in the liquid crystal aligning agent of the present invention is a polymer selected from polyimide and a precursor thereof, and has at least one group selected from a vertical alignment group and a tertiary butoxycarbonyl group, The polymer is at least one of chemically imidized.

The polymer of the component (B) is a polyimide and a precursor thereof (hereinafter, also referred to as a polyimide component), and has a surface energy close to that of the polymer as the component (A). An acrylic component such as the component (A) basically has low polarity and low surface energy. On the other hand, the polyimide component has a high polarity and a high surface energy. However, if the difference between the surface energies of these two components is too large, the two components will not be compatible with each other and coagulation will occur, resulting in a film with irregularities, or a process margin will be reduced due to repelling or unevenness. Such a problem may occur. Thus, by lowering the polarity of the polyimide component, it is possible to control the surface energy to a value that is higher than that of the acrylic component but has a smaller difference. As a method for lowering the polarity of the polyimide component, there is a method of chemically imidizing and then mixing with the component (A), or a method of introducing a side chain.

As such a polymer, a polymer obtained by polymerizing a tetracarboxylic acid derivative such as a known tetracarboxylic dianhydride and a known diamine, and then chemically imidizing the polymer, using a diamine having a side chain. Examples include a polyimide precursor obtained, a polyimide obtained by imidizing the same, a polyimide precursor obtained by using a diamine having a tertiary butoxycarbonyloxy group, and a polyimide obtained by imidating the same. Such side chains and chemical imidization make it possible to bring the surface energy close to that of the acrylic polymer as the component (A). Therefore, when a liquid crystal aligning agent is applied and fired to form a cured film, aggregation or the like occurs. This does not occur, and a flat cured film can be provided. Examples of the diamine having a side chain include diamines represented by formulas (2), (3), (4) and (5) described in paragraphs [0023] to [0039] of International Patent Application Publication No. WO2016 / 125870. Specific examples thereof include diamines represented by formulas [A-1] to [A-32]. Examples of the diamine having a tertiary butoxycarbonyloxy group include those represented by formulas [A-1], [A-2] and [A-3] described in paragraphs [0011] to [0034] of International Patent Application Publication No. WO2017 / 119461. Diamines having a structure and diamines exemplified as specific examples thereof are exemplified.

In the liquid crystal aligning agent of the present invention, the content ratio of the polymer as the component (A) to the polymer as the component (B) is such that the mass ratio of the component (A) to the component (B) is 5:95 to 95: 5. It is more preferably 10:90 to 90:10, and further preferably 20:80 to 60:40.

<(C) component>
When the liquid crystal aligning agent used in the present invention satisfies the requirement Z2, a crosslinking agent is contained as the component (C). As the component (C), a crosslinking agent having two or more thermally crosslinkable groups B is exemplified.

Examples of the crosslinking agent (C) include epoxy compounds, compounds having two or more amino groups, low molecular weight compounds such as methylol compounds, isocyanate compounds, phenoplast compounds, and blocked isocyanate compounds, and polymers of N-alkoxymethylacrylamide. And a polymer such as a polymer of a compound having an epoxy group and a polymer of a compound having an isocyanate group.

Specific examples of the epoxy compound described above include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, 1, 6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 1,3,5,6-tetraglycidyl-2,4-hexanediol, N, N, N ', N ',-tetraglycidyl-m-xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, and N, N, N', N'-tetraglycidi 4,4'-diaminodiphenylmethane and the like.

Examples of compounds having two or more amino groups include diamines such as alicyclic diamines, aromatic diamines, aromatic-aliphatic diamines, and aliphatic diamines.

Examples of alicyclic diamines include 1,4-diaminocyclohexane, 1,3-diaminocyclohexane, 4,4′-diaminodicyclohexylmethane, 4,4′-diamino-3,3′-dimethyldicyclohexylamine, isophorone Diamines and the like can be mentioned.

Examples of aromatic diamines include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, 3,5-diaminotoluene, 1,4-diamino -2-methoxybenzene, 2,5-diamino-p-xylene and 1,3-diamino-4-chlorobenzene.

Examples of aromatic-aliphatic diamines include 3-aminobenzylamine, 4-aminobenzylamine, 3-amino-N-methylbenzylamine, 4-amino-N-methylbenzylamine, 3-aminophenethylamine, Aminophenethylamine, 3-amino-N-methylphenethylamine, 4-amino-N-methylphenethylamine, 3- (3-aminopropyl) aniline, 4- (3-aminopropyl) aniline, 3- (3-methylaminopropyl) Aniline, 4- (3-methylaminopropyl) aniline, 3- (4-aminobutyl) aniline, 4- (4-aminobutyl) aniline, 3- (4-methylaminobutyl) aniline, 4- (4-methyl Aminobutyl) aniline, 3- (5-aminopentyl) aniline, 4- (5-aminopentyl) Aniline, 3- (5-methylaminopentyl) aniline, 4- (5-methylaminopentyl) aniline, 2- (6-aminonaphthyl) methylamine, 3- (6-aminonaphthyl) methylamine, 2- (6 -Aminonaphthyl) ethylamine, 3- (6-aminonaphthyl) ethylamine and the like.

Examples of the aliphatic diamines include 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, and 1,7-diaminoheptane 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,3-diamino-2,2-dimethylpropane, 1,6-diamino-2,5-dimethylhexane, 1,7 -Diamino-2,5-dimethylheptane, 1,7-diamino-4,4-dimethylheptane, 1,7-diamino-3-methylheptane, 1,9-diamino-5-methylheptane and the like.

Specific examples of the methylol compound include compounds such as alkoxymethylated glycoluril, alkoxymethylated benzoguanamine, and alkoxymethylated melamine.

Specific examples of the alkoxymethylated glycoluril include, for example, 1,3,4,6-tetrakis (methoxymethyl) glycoluril, 1,3,4,6-tetrakis (butoxymethyl) glycoluril, 1,3,4 1,6-Trikis (hydroxymethyl) glycoluril, 1,3-bis (hydroxymethyl) urea, 1,1,3,3-tetrakis (butoxymethyl) urea, 1,1,3,3-tetrakis (methoxymethyl) Urea, 1,3-bis (hydroxymethyl) -4,5-dihydroxy-2-imidazolinone, and 1,3-bis (methoxymethyl) -4,5-dimethoxy-2-imidazolinone. As commercially available products, compounds such as glycoluril compounds (trade names: Cymel (registered trademark) 1170, powder link (registered trademark) 1174) manufactured by Mitsui Cytec Co., Ltd., and methylated urea resins (trade name: UFR (registered trademark) 65) ), Butylated urea resin (trade name: UFR (registered trademark) 300, U-VAN10S60, U-VAN10R, U-VAN11HV), urea / formaldehyde-based resin manufactured by DIC (highly condensed, trade name: becamine ( (Registered trademark) J-300S, P-955, and N).

Specific examples of the alkoxymethylated benzoguanamine include, for example, tetramethoxymethylbenzoguanamine and the like. Commercial products include Mitsui Cytec Co., Ltd. (trade name: Cymel (registered trademark) 1123) and Sanwa Chemical Co., Ltd. (trade name: Nicarack (registered trademark) BX-4000, BX-37, and BL-). 60 and BX-55H).

Specific examples of the alkoxymethylated melamine include, for example, hexamethoxymethylmelamine. Commercially available products include methoxymethyl type melamine compounds (trade names: Cymel (registered trademark) 300, 301, 303, and 350) and butoxymethyl type melamine compounds (trade name: Mycoat (registered trademark) manufactured by Mitsui Cytec Co., Ltd.) 506, 508), a methoxymethyl type melamine compound manufactured by Sanwa Chemical Co., Ltd. (trade name: Nicalac (registered trademark) MW-30, MW-22, MW-11, MS-001, MX-002, MX-002) MX-730, MX-750, and MX-035), butoxymethyl-type melamine compounds (trade names: Niclac (registered trademark) MX-45, MX-410, and MX-302).

A compound obtained by condensing a melamine compound, a urea compound, a glycoluril compound and a benzoguanamine compound in which the hydrogen atom of the amino group is substituted with a methylol group or an alkoxymethyl group may be used. For example, high molecular weight compounds produced from melamine compounds and benzoguanamine compounds described in US Pat. No. 6,323,310 are mentioned. Commercial products of the melamine compound include Cymel (registered trademark) 303 (manufactured by Mitsui Cytec Co., Ltd.) and the like. Commercial products of the benzoguanamine compound include a commercial name of Cymel (registered trademark) 1123 ( (Mitsui Cytec Co., Ltd.).

Specific examples of the isocyanate compound include, for example, VESTANAT B1358 / 100, VESTAGON BF1540 (above, isocyanurate-type modified polyisocyanate, manufactured by Degussa Japan KK), Takenate (registered trademark) B-882N, and B-7075 ( As described above, isocyanurate-type modified polyisocyanates, manufactured by Mitsui Chemicals, Inc.) and the like.

具体 Specific examples of the phenoplast compound include the following compounds, but the phenoplast compound is not limited to the following compound examples.

Specific examples of the compound having two or more hydroxyalkylamide groups at the molecular terminal include the following compounds and Primid XL-552 and Primid SF-4510.

Examples of the blocked isocyanate compound include Coronate AP Stable M, Coronate 2503, 2515, 2507, 2513, 2555, Millionate MS-50 (all manufactured by Nippon Polyurethane Industry Co., Ltd.), Takenate B-830, B-815N, B-820NSU, B-842N, B-846N, B-870N, B-874N, B-882N (all manufactured by Mitsui Chemicals, Inc.) and the like.

Further, examples of the above-mentioned polymer of N-alkoxymethylacrylamide include N-hydroxymethyl (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-ethoxymethyl (meth) acrylamide, N-butoxymethyl (meth) ) Polymers produced using acrylamide compounds or methacrylamide compounds substituted with a hydroxymethyl or alkoxymethyl group such as acrylamide.

Specific examples of such a polymer include poly (N-butoxymethylacrylamide), a copolymer of N-butoxymethylacrylamide and styrene, a copolymer of N-hydroxymethylmethacrylamide and methyl methacrylate, -A copolymer of ethoxymethyl methacrylamide and benzyl methacrylate, and a copolymer of N-butoxymethyl acrylamide, benzyl methacrylate and 2-hydroxypropyl methacrylate. The weight average molecular weight of such a polymer is from 1,000 to 200,000, more preferably from 3,000 to 150,000, and even more preferably from 3,000 to 50,000.

Examples of the polymer of the compound having an epoxy group include polymers produced using a compound having an epoxy group such as glycidyl methacrylate, 3,4-epoxycyclohexylmethyl methacrylate, and 3,4-epoxycyclohexylmethyl methacrylate. Can be

Specific examples of such a polymer include, for example, poly (3,4-epoxycyclohexylmethyl methacrylate), poly (glycidyl methacrylate), a copolymer of glycidyl methacrylate and methyl methacrylate, and 3,4-epoxycyclohexylmethyl methacrylate. Copolymers of methyl methacrylate, copolymers of glycidyl methacrylate and styrene, and the like are included. The weight average molecular weight of such a polymer is from 1,000 to 200,000, more preferably from 3,000 to 150,000, and even more preferably from 3,000 to 50,000.

Examples of the polymer of the above-mentioned compound having an isocyanate group include 2-isocyanatoethyl methacrylate (Karenz MOI (registered trademark), manufactured by Showa Denko KK) and 2-isocyanatoethyl acrylate (kalenz AOI (registered trademark)). Or a compound having an isocyanate group, such as manufactured by Showa Denko KK, or 2- (0- [1′-methylpropylideneamino] carboxyamino) ethyl methacrylate (Karenz MOI-BM [registered trademark], Showa Denko KK )) And 2-[(3,5-dimethylpyrazolyl) carbonylamino] ethyl methacrylate (Karenz MOI-BP (registered trademark), manufactured by Showa Denko KK). Polymer.

Specific examples of such a polymer include, for example, poly (2-isocyanatoethyl acrylate), poly (2- (0- [1′-methylpropylideneamino] carboxyamino) ethyl methacrylate), 2-isocyanatoethyl Examples include a copolymer of methacrylate and styrene, and a copolymer of 2-[(3,5-dimethylpyrazolyl) carbonylamino] ethyl methacrylate and methyl methacrylate. The weight average molecular weight of such a polymer is from 1,000 to 200,000, more preferably from 3,000 to 150,000, and even more preferably from 3,000 to 50,000.

These crosslinking agents can be used alone or in combination of two or more.

When the liquid crystal aligning agent used in the present invention contains the crosslinking agent of the component (C), the content is preferably from 1 to 100 parts by mass based on 100 parts by mass of the resin as the component (A). And more preferably 1 to 80 parts by mass.

[Preparation of liquid crystal aligning agent]
The liquid crystal alignment agent used in the present invention is preferably prepared as a coating liquid so as to be suitable for forming a liquid crystal alignment film. That is, the liquid crystal alignment agent of the present invention is preferably prepared as a solution in which a resin component for forming a resin film is dissolved in an organic solvent. Here, the resin component is the specific polymer as the component (A) and the polymer as the component (B) described above. At that time, the total of the content of the specific polymer as the component (A) and the content of the polymer as the component (B) is preferably from 0.5 to 20% by mass, more preferably from the whole liquid crystal aligning agent. Is preferably 1 to 20% by mass, more preferably 1 to 15% by mass, particularly preferably 1 to 10% by mass.

<Solvent>
The solvent contained in the liquid crystal aligning agent used in the present invention is not particularly limited as long as the solvent dissolves the component (A), the component (B), and the component (C) as required. The solvent contained in the liquid crystal aligning agent may be one kind or a mixture of two or more kinds. Further, even if the solvent does not dissolve the component (A) or the component (B), it can be used in combination with a solvent that dissolves the component (A) or the component (B). In this case, if the surface energy of the solvent that does not dissolve the component (A) or the component (B) is lower than the solvent that dissolves the component (A) or the component (B), the applicability of the liquid crystal alignment agent to the substrate is improved. It is preferable because it can be performed.

Specific examples include water, N-alkyl-2-pyrrolidones such as N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylcaprolactam , Tetramethylurea, 3-methoxy-N, N-dimethylpropanamide, 3-ethoxy-N, N-dimethylpropanamide, 3-butoxy-N, N-dimethylpropanamide, 1,3-dimethyl-2-imidazo Dialkyl imidazolidinones such as lydinone, lactones such as γ-butyrolactone, γ-valerolactone and δ-valerolactone, carbonates such as ethylene carbonate and propylene carbonate, methanol, ethanol, propanol, isopropanol and 3-methyl- 3-methoxybutanol, ethyl Ketones such as milk ketone, methyl nonyl ketone, methyl ethyl ketone, isoamyl methyl ketone, methyl isopropyl ketone, diisobutyl ketone, cyclohexanone, cyclopentanone, methyl isobutyl ketone and 4-hydroxy-4-methyl-2-pentanone; Compound represented by 1) and a compound represented by the following formula (Sv-2), 4-methyl-2-pentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, cyclohexyl acetate, 2-methylcyclohexyl acetate, butyric acid Butyl, isoamyl butyrate, diisobutylcarbinol, diisopentyl ether and the like.

In the formulas (Sv-1) to (Sv-2), Y ₁ and Y ₂ are each independently a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms, and X ₁ is an oxygen atom or —COO— X 2 is a single bond or a carbonyl group, and R ₁ is an alkanediyl group having 2 to 4 carbon atoms. n ₁ is an integer of 1 to 3. When n ₁ is 2 or 3, a plurality of R ₁ may be the same or different. Z ₁ is a divalent hydrocarbon group having 1 to 6 carbon atoms, and Y ₃ and Y ₄ are each independently a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbon atoms).

In the formula (Sv-1), examples of the monovalent hydrocarbon group having 1 to 6 carbon atoms of Y ₁ and Y ₂ include a monovalent linear hydrocarbon group having 1 to 6 carbon atoms and a monovalent hydrocarbon group having 1 to 6 carbon atoms. Examples thereof include a monovalent alicyclic hydrocarbon group and a monovalent aromatic hydrocarbon group having 1 to 6 carbon atoms. Examples of the monovalent chain hydrocarbon group having 1 to 6 carbon atoms include an alkyl group having 1 to 6 carbon atoms. The alkanediyl group for R ₁ may be linear or branched.

In the formula (Sv-2), examples of the divalent hydrocarbon group having 1 to 6 carbon atoms for Z ₁ include an alkanediyl group having 1 to 6 carbon atoms.
Examples of the monovalent hydrocarbon group having 1 to 6 carbon atoms of Y ₃ and Y ₄ include a monovalent linear hydrocarbon group having 1 to 6 carbon atoms and a monovalent alicyclic hydrocarbon having 1 to 6 carbon atoms. And monovalent aromatic hydrocarbon groups having 1 to 6 carbon atoms. Examples of the monovalent chain hydrocarbon group having 1 to 6 carbon atoms include an alkyl group having 1 to 6 carbon atoms.

Specific examples of the solvent represented by the formula (Sv-1) include, for example, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-i-propyl ether, ethylene glycol monobutyl ether ( Butyl cellosolve), ethylene glycol monohexyl ether, ethylene glycol dimethyl ether, ethylene glycol monoacetate, ethylene glycol diacetate, 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, die Lenglycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether, dipropylene glycol dimethyl ether, dipropylene glycol monomethyl ether, propylene glycol diacetate, ethylene glycol, 1,4-butanediol, 3-methoxybutyl acetate, 3-ethoxybutyl acetate and the like;
Specific examples of the solvent represented by (Sv-2) include, for example, methyl glycolate, ethyl glycolate, butyl glycolate, ethyl lactate, butyl lactate, isoamyl lactate, ethyl-3-ethoxypropionate, methyl-3 Examples include -methoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionic acid, 3-methoxypropionic acid, propyl 3-methoxypropionate, and butyl 3-methoxypropionate.

The solvent preferably has a boiling point of 80 to 200 ° C. More preferably, the temperature is from 80 ° C. to 180 ° C., and preferred solvents include N, N-dimethylformamide, tetramethylurea, 3-methoxy-N, N-dimethylpropanamide, propanol, isopropanol, 3-methyl-3-methoxy Butanol, ethyl amyl ketone, methyl ethyl ketone, isoamyl methyl ketone, methyl isopropyl ketone, diisobutyl ketone, cyclohexanone, cyclopentanone, methyl isobutyl ketone, 4-hydroxy-4-methyl-2-pentanone, 4-methyl-2-pentyl acetate, 2-ethylbutyl acetate, cyclohexyl acetate, 2-methylcyclohexyl acetate, butyl butyrate, isoamyl butyrate, diisobutyl carbinol, diisopentyl ether, ethylene glycol monomethyl ether, ethylene glycol Monoethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-i-propyl ether, ethylene glycol monobutyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol monoacetate, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol Diethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether, dipropylene glycol dimethyl ether, dipropylene glycol monomethyl ether, 3-methoxybutyl acetate, methyl glycolate, glyco Ethyl Le acid, butyl glycolate, ethyl lactate, butyl lactate, isoamyl, ethyl 3-ethoxypropionate, methyl 3-methoxy propionate, 3-methoxy ethyl propionate, and the like.
It is particularly preferable that the boiling point is in this range when the liquid crystal aligning agent containing the solvent is applied onto a plastic substrate described later.

<Other components>
The liquid crystal aligning agent used in the present invention may contain components other than the above components (A) and (B) and optionally the above component (C). Examples of such other components include a crosslinking catalyst, a compound that improves the uniformity of the film thickness and surface smoothness when a liquid crystal alignment agent is applied, a compound that improves the adhesion between the liquid crystal alignment film and the substrate, and the like. But not limited thereto.

<Cross-linking catalyst>
A crosslinking catalyst may be added to the liquid crystal aligning agent used in the present invention for the purpose of accelerating the reaction between the thermally crosslinkable group A and the thermally crosslinkable group B. Examples of such a crosslinking catalyst include p-toluenesulfonic acid, camphorsulfonic acid, trifluoromethanesulfonic acid, p-phenolsulfonic acid, 2-naphthalenesulfonic acid, mesitylenesulfonic acid, p-xylene-2-sulfonic acid, m- Xylene-2-sulfonic acid, 4-ethylbenzenesulfonic acid, 1H, 1H, 2H, 2H-perfluorooctanesulfonic acid, perfluoro (2-ethoxyethane) sulfonic acid, pentafluoroethanesulfonic acid, nonafluorobutane-1- Examples thereof include sulfonic acids such as sulfonic acid and dodecylbenzenesulfonic acid, and hydrates and salts thereof. Examples of the compound that generates an acid by heat include bis (tosyloxy) ethane, bis (tosyloxy) propane, bis (tosyloxy) butane, p-nitrobenzyl tosylate, o-nitrobenzyl tosylate, 1,2,3- Phenylentris (methyl sulfonate), p-toluenesulfonic acid pyridinium salt, p-toluenesulfonic acid morphonium salt, p-toluenesulfonic acid ethyl ester, p-toluenesulfonic acid propyl ester, p-toluenesulfonic acid butyl ester, p-toluenesulfonic acid butyl ester Toluenesulfonic acid isobutyl ester, p-toluenesulfonic acid methyl ester, p-toluenesulfonic acid phenethyl ester, cyanomethyl p-toluenesulfonate, 2,2,2-trifluoroethyl p-toluenesulfonate, 2-hydroxy Chill p- toluenesulfonate, N- ethyl -p- toluenesulfonamide, and the like.

[Compound that improves uniformity of film thickness and surface smoothness]
Examples of the compound that improves the uniformity of the film thickness and the surface smoothness include a fluorine-based surfactant, a silicone-based surfactant, and a nonion-based surfactant.
Specifically, for example, F-Top (registered trademark) 301, EF303, EF352 (manufactured by Tochem Products), Megafac (registered trademark) F171, F173, R-30 (manufactured by DIC), Florard FC430, FC431 ( Sumitomo 3M Co., Ltd.), Asahi Guard (registered trademark) AG710 (produced by Asahi Glass Co., Ltd.), Surflon (registered trademark) S-382, SC101, SC102, SC103, SC104, SC105, SC105 (manufactured by AGC Seimi Chemical Co., Ltd.) and the like. .
The use ratio of these surfactants is preferably from 0.01 to 2 parts by mass, more preferably from 0.01 to 1 part by mass, per 100 parts by mass of the resin component contained in the polymer composition. Parts by weight.

[Compound that improves adhesion between liquid crystal alignment film and substrate]
Specific examples of the compound that improves the adhesion between the liquid crystal alignment film and the substrate include the following functional silane-containing compounds.
For example, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxy Carbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7-triazadecane, 10-to Ethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, N-benzyl-3-aminopropyltri Methoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis (oxyethylene) -3-amino Amino silane-containing compounds such as propyltrimethoxysilane and N-bis (oxyethylene) -3-aminopropyltriethoxysilane.
When a compound that improves the adhesion to the substrate is used, the amount used is preferably from 0.1 to 30 parts by mass based on 100 parts by mass of the resin component contained in the polymer composition. More preferably, it is 1 part by mass to 20 parts by mass.

In one embodiment, a photosensitizer may be used as an additive to improve the photoreactivity of the photo-alignment group. Specific examples include aromatic 2-hydroxyketone (benzophenone), coumarin, ketocoumarin, carbonylbiscoumarin, acetophenone, anthraquinone, xanthone, thioxanthone, and acetophenone ketal.

<Liquid crystal alignment film and liquid crystal display element>
After the liquid crystal aligning agent of the present invention is applied and baked on a substrate, it may be subjected to an alignment treatment by rubbing treatment or light irradiation, or may be a liquid crystal alignment film without an alignment treatment in some vertical alignment applications. it can. As the substrate, for example, glass such as float glass and soda glass; polyethylene terephthalate, polybutylene terephthalate, polypropylene, polystyrene, polyether sulfone, polycarbonate, poly (alicyclic olefin), polyvinyl chloride, polyvinylidene chloride, polyether ether A transparent substrate made of a plastic such as ketone (PEEK) resin film, polysulfone (PSF), polyethersulfone (PES), polyamide, polyimide, acryl, and triacetyl cellulose can be used.
As the transparent conductive film provided on one surface of a substrate, NESA film (US PPG registered trademark) made of tin oxide (SnO _2), indium oxide - such as an ITO film made of tin oxide _(In ₂ O 3 -SnO ₂₎ the Can be used.

<Coating process>
The method for applying the liquid crystal aligning agent of the present invention is not particularly limited, but includes screen printing, flexographic printing, offset printing, inkjet, dip coating, roll coating, slit coating, spin coating, and the like. Good. After coating on the substrate by these methods, the solvent can be evaporated by a heating means such as a hot plate to form a coating film.

The baking after the application of the liquid crystal aligning agent can be performed at any temperature of 40 to 300 ° C., preferably 40 to 250 ° C., more preferably 40 to 230 ° C.
The thickness of the coating film formed on the substrate is preferably 5 to 1,000 nm, more preferably 10 to 500 nm or 10 to 300 nm. This firing can be performed in a hot plate, a hot air circulating furnace, an infrared furnace, or the like.
For the rubbing treatment, rayon cloth, nylon cloth, cotton cloth and the like can be used.

<Light irradiation step>
In one embodiment, alignment treatment by light irradiation may be performed, for example, a step of forming a coating film by applying the above-described liquid crystal alignment agent on a substrate, or in a state where the coating film is not in contact with a liquid crystal layer or Irradiating the coating film with light while in contact with the liquid crystal layer.

(4) Examples of the light irradiated in the alignment treatment by light irradiation include ultraviolet light including visible light having a wavelength of 150 to 800 nm, and visible light. Among them, ultraviolet rays containing light having a wavelength of 300 to 400 nm are preferable. The irradiation light may be polarized or unpolarized. It is preferable to use light containing linearly polarized light as the polarized light.

When the light to be used is polarized light, the light irradiation may be performed from a direction perpendicular to the substrate surface, from an oblique direction, or a combination thereof. Irradiation with non-polarized light is preferably performed from a direction oblique to the substrate surface.
The dose of light is preferably set to 0.1 mJ / cm ² or more 1,000 mJ / cm less than ^2, more preferably, to 1 ~ 500 mJ / cm ^2, it is 2 ~ 200 mJ / cm ² further preferable.

液晶 The liquid crystal display device of the present invention can be manufactured by a usual method, and the manufacturing method is not particularly limited. It is preferable that the pair of substrates face each other with an appropriate gap therebetween and a spacer is disposed between the substrates for the purpose of making the thickness of the liquid crystal interposed between the substrates uniform. As the spacer, a known spacer material such as a conventional scatter-type spacer, a spacer formed from a photosensitive spacer-forming composition can be used, and irregularities formed in a layer made of a cured liquid crystal can be used. It is also possible to use it as a spacer.

<Liquid crystal sandwiching process>
In order to constitute a liquid crystal cell by sandwiching liquid crystal between substrates, the following two methods can be exemplified. As a first method, a pair of substrates is opposed to each other with a gap (cell gap) therebetween so that the liquid crystal alignment films face each other, and the peripheral portions of the pair of substrates are attached to each other using a sealant, and the substrate surface and A method of manufacturing a liquid crystal cell by injecting and filling a liquid crystal into a cell gap defined by an appropriate sealant, and then sealing the injection hole.

As a second method, for example, an ultraviolet-curable sealing material is applied to a predetermined location on one of the two substrates on which the liquid crystal alignment film is formed, and a predetermined number of locations are applied to the liquid crystal alignment film surface. After the liquid crystal is dropped, the other substrate is adhered so that the liquid crystal alignment film faces and the liquid crystal is spread over the entire substrate, and then the entire surface of the substrate is irradiated with ultraviolet light to cure the sealant. A method for manufacturing a cell (ODF (One Drop Fill) method) can be exemplified.

As the liquid crystal, a fluorine-based liquid crystal or a cyano-based liquid crystal having a positive or negative dielectric anisotropy depending on the use, a liquid crystal compound or a liquid crystal composition polymerized by at least one treatment of heating and light irradiation ( Hereinafter, a polymerizable liquid crystal or a curable liquid crystal composition) may be used.
In one embodiment, the step of forming a coating film of the liquid crystal alignment agent may be performed by a roll-to-roll method. When performed by the roll-to-roll method, the manufacturing process of the liquid crystal display element can be simplified, and the manufacturing cost can be reduced.
Then, by attaching a polarizing plate to both outer surfaces of the liquid crystal cell, a liquid crystal display device can be obtained.

The polarizing plate used on the outside of the liquid crystal cell is composed of a polarizing plate in which a polarizing film called "H film" in which polyvinyl alcohol is stretched and oriented while absorbing iodine is sandwiched by a cellulose acetate protective film or the H film itself. A polarizing plate and the like can be given.
As described above, the liquid crystal alignment film obtained from the liquid crystal alignment agent of the present invention has good liquid crystal alignment properties, excellent pretilt angle developing ability, and high reliability. Further, the liquid crystal display device manufactured by the method of the present invention has excellent display characteristics.

The abbreviations used in the examples are as follows.
<Methacrylic monomer>
(Photo-alignable monomer)
“MA1” was synthesized by a synthesis method described in Patent Document (WO2017 / 1155791).
"MA2" was synthesized by the synthesis method described in Patent Document (WO2017 / 1155791).

(Polar monomer)
MAA: Methacrylic acid

(Crosslinkable monomer)
GMA: Glycidyl methacrylate

(Isocyanate monomer)
MOI-BP: 2-[(3,5-dimethyl-1-pyrazolyl) carbonylamino] ethyl methacrylate

<Tetracarboxylic dianhydride monomer>
A1: Tetracarboxylic dianhydride represented by the following formula [A1] A2: Tetracarboxylic dianhydride represented by the following formula [A2] A3: Tetracarboxylic dianhydride represented by the following formula [A3] Compound A4: Tetracarboxylic dianhydride A5 represented by the following formula [A4]: Tetracarboxylic dianhydride A6 represented by the following formula [A5]: Tetracarboxylic dianhydride represented by the following formula [A6] Anhydride A7: Tetracarboxylic dianhydride represented by the following formula [A7] A8: Tetracarboxylic dianhydride represented by the following formula [A8]

<Side chain diamine monomer>
B1: Side chain diamine monomer represented by the following formula [B1] B2: Side chain diamine monomer B3 represented by the following formula [B2]: Side chain diamine monomer B4 represented by the following formula [B3] B4: The following formula Side chain diamine monomer B5 represented by [B4]: Side chain diamine monomer B6 represented by the following formula [B5]: Side chain diamine monomer B7 represented by the following formula [B6]: Represented by the following formula [B7] Side chain diamine monomer B8: Side chain diamine monomer B9 represented by the following formula [B8]: Side chain diamine monomer B10 represented by the following formula [B9]: Side chain diamine monomer represented by the following formula [B10] B11: Side-chain diamine monomer B12 represented by the following formula [B11]: Side-chain diamine monomer B13 represented by the following formula [B12]: In the following formula [B13] Is the side chain diamine monomer B14: side chain diamine monomer represented by the following formula [B14]

<Other diamine monomers>
C1: Other diamine monomer C2 represented by the following formula [C1]: Other diamine monomer C3 represented by the following formula [C2]: Other diamine monomer C4 represented by the following formula [C3]: The following formula [C4] Other diamine monomer C5 represented by the following formula: Other diamine monomer C6 represented by the following formula [C5]: Other diamine monomer C7 represented by the following formula [C6]: Other diamine monomer C8 represented by the following formula [C7]: Other diamine monomer C9 represented by the following formula [C8]: Other diamine monomer C10 represented by the following formula [C9]: Other diamine monomer C11 represented by the following formula [C10]: Represented by the following formula [C11] Other diamine monomer C12: Other diamine monomer C13 represented by the following formula [C12] Other diamine monomer C14 represented by the following formula [C13]: Other diamine monomer C15 represented by the following formula [C14]: Other diamine monomer C16 represented by the following formula [C15]: Represented by the following formula [C16] Other diamine monomer C17: other diamine monomer C18 represented by the following formula [C17]: other diamine monomer C19 represented by the following formula [C18]: other diamine monomer C20 represented by the following formula [C19]: Other diamine monomers represented by the formula [C20]

(Crosslinking agent component)
D-1: Crosslinking agent component represented by the following formula [D1] D-2: Crosslinking agent component represented by the following formula [D2] D-3: Crosslinking agent component represented by the following formula [D3]

The abbreviations of the reagents used in this example are shown below.
(Polymerization initiator)
AIBN: azobisisobutyronitrile (solvent)
NMP: N-methyl-2-pyrrolidone BCS: butyl cellosolve THF: tetrahydrofuran DMF: N, N-dimethylformamide

(Molecular weight measurement)
The molecular weight of the polymer in the synthesis example was measured as follows using a room temperature gel permeation chromatography (GPC) device (SSC-7200, manufactured by Shodex) and columns (KD-803, KD-805) manufactured by Shodex.
Column temperature: 50 ° C., eluent: DMF (as an additive, lithium bromide-hydrate (LiBr.H ₂ O) 30 mmol / L, phosphoric acid / anhydrous crystal (o-phosphoric acid) 30 mmol / L, THF is 10 ml / L), flow rate: 1.0 ml / min.
Standard samples for preparing a calibration curve: TSK standard polyethylene oxide (molecular weight: about 9,000,000, 150,000, 100,000, 30,000) manufactured by Tosoh Corporation, and polyethylene glycol (molecular weight: about 12,000, molecular weight: 12,000, manufactured by Polymer Laboratories) 000, 1,000).

(Imidation rate measurement)
The imidation ratio in the synthesis example was measured as follows. 20 mg of polyimide powder is put into an NMR sample tube (NMR sampling tube standard φ5 manufactured by Kusano Science Co., Ltd.), 1.0 ml of deuterated dimethyl sulfoxide (DMSO-d6, 0.05% TMS mixture) is added, and ultrasonic waves are applied. And completely dissolved. The solution was subjected to 500 MHz proton NMR measurement using an NMR spectrometer (JNW-ECA500) manufactured by JEOL Datum. The imidation rate is determined by determining a proton derived from a structure that does not change before and after imidation as a reference proton. The peak integrated value of this proton and the proton peak derived from the NH group of amic acid appearing in the vicinity of 9.5 to 10.0 ppm are determined. It was determined by the following equation using the integrated value. In the following formula, x is the integrated value of the proton peak derived from the NH group of the amic acid, y is the integrated value of the peak of the reference proton, α is the proton of the NH group of the amic acid in the case of polyamic acid (imidation ratio is 0%). This is a ratio of the number of reference protons to one.
Imidation ratio (%) = (1−α · x / y) × 100

<Synthesis example 1 of methacrylate polymer>
MA1 (1.65 g, 4.00 mmol) and MAA (1.38 g, 16.00 mmol) were dissolved in NMP (18.1 g), deaerated by a diaphragm pump, and then AIBN (0. .16 g, 0.5 mmol) and degassed again. Thereafter, the mixture was reacted at 60 ° C. for 13 hours to obtain a polymer solution.
Next, NMP (5.0 g) and BCS (6.0 g) were added to the polymer solution (4.0 g) and stirred at room temperature to obtain a methacrylate polymer solution (MP1).
The number average molecular weight of this polymer was 34,200, and the weight average molecular weight was 116,000.

<Methacrylate polymer synthesis example 2>
MA1 (3.30 g, 8.00 mmol), GMA (0.56 g, 4.00 mmol) and MAA (0.69 g, 8.00 mmol) were dissolved in NMP (26.8 g) and degassed with a diaphragm pump. After that, AIBN (0.16 g, 0.5 mmol) was added as a polymerization initiator, and the mixture was degassed again. Thereafter, the mixture was reacted at 60 ° C. for 13 hours to obtain a polymer solution.
Next, NMP (5.0 g) and BCS (6.0 g) were added to the polymer solution (4.0 g), and the mixture was stirred at room temperature to obtain a methacrylate polymer solution (MP2).
The number average molecular weight of this polymer was 45,000, and the weight average molecular weight was 150,000.

<Methacrylate polymer synthesis example 3>
MA1 (2.48 g, 6.00 mmol) and MOI-BP (3.52 g, 14.00 mmol) were dissolved in NMP (34.9 g), degassed by a diaphragm pump, and then AIBN was used as a polymerization initiator. (0.16 g, 0.5 mmol) and degassed again. Thereafter, the mixture was reacted at 60 ° C. for 13 hours to obtain a polymer solution.
Next, NMP (5.0 g) and BCS (6.0 g) were added to the polymer solution (4.0 g), and the mixture was stirred at room temperature to obtain a methacrylate polymer solution (MP3).
The number average molecular weight of this polymer was 48,000, and the weight average molecular weight was 148,000.

<Polyamic acid polymer synthesis example 4>
B1 (2.28 g, 3.00 mmol), C2 (1.22 g, 4.00 mmol), C7 (1.45 g, 3.00 mmol) and A1 (2.23 g, 6.00 mmol) were NMP (27.2 g). After reacting at 60 ° C. for 5 hours, A2 (1.00 g, 2.00 mmol) and A4 (0.87 g, 2.00 mmol) and NMP (9.1 g) were added. The reaction was carried out for a time to obtain a polyamic acid polymer solution (MP4).

<Polyamic acid polymer synthesis examples 5 to 20>
Using the composition shown in Table 1, polyamic acid polymer solutions MP5 to MP20 were synthesized in the same manner as in Polymer Synthesis Example 1.

<Amic acid polymer synthesis example 21>
C8 (5.17 g, 5.00 mmol) and A4 (2.18 g, 10.00 mmol) were dissolved in NMP (26.6 g) and reacted at 60 ° C. for 5 hours. .00 mmol) and NMP (9.5 g) were added and reacted at 40 ° C. for 10 hours to obtain a polyamic acid polymer solution (MP21).

<Synthesis example 22 of amic acid polymer>
C2 (0.61 g, 2.00 mmol), C11 (3.19 g, 8.00 mmol) and A2 (2.50 g, 5.00 mmol) were dissolved in NMP (24.78 g) and reacted at 60 ° C. for 5 hours. After that, A1 (1.96 g, 5.00 mmol) and NMP (8.26 g) were added and reacted at 40 ° C. for 10 hours to obtain a polyamic acid polymer solution (MP22).

<Synthesis example 23 of polyimide polymer>
After adding NMP to the polyamic acid polymer solution (MP4) (50 g) and diluting it to 6.5% by mass, acetic anhydride (8.8 g) and pyridine (2.7 g) were added as imidation catalysts. The reaction was performed for 5 hours. This reaction solution was poured into methanol (700 ml), and the obtained precipitate was separated by filtration. The precipitate was washed with methanol and dried at 100 ° C. under reduced pressure to obtain a polyimide polymer powder (E). The imidation ratio of this polyimide polymer was 71%, the number average molecular weight was 13,000, and the weight average molecular weight was 42,000.

ＮNMP (44.0 g) was added to the obtained polyimide powder (E) (6.0 g), and the mixture was stirred at 70 ° C. for 20 hours to be dissolved. NMP (10.0 g) and BCS (40.0 g) were added to this solution, and the mixture was stirred at room temperature for 5 hours to obtain a polyimide polymer solution (MP23).

<Synthesis examples of polyimide polymers 24 and 25>
Using the polymer solutions obtained in Polymer Synthesis Examples 21 and 22, polyimide polymer solutions (MP24) and (MP25) were synthesized in the same manner as in Polymer Synthesis Example 23.

<Methacrylate polymer synthesis example 26>
MA2 (3.04 g, 6.00 mmol), GMA (0.71 g, 5.00 mmol) and MAA (0.77 g, 9.00 mmol) were dissolved in NMP (18.8 g) and degassed with a diaphragm pump. After that, AIBN (0.16 g, 0.5 mmol) was added as a polymerization initiator, and the mixture was degassed again. Thereafter, the mixture was reacted at 60 ° C. for 13 hours to obtain a polymer solution.
Next, NMP (5.0 g) and BCS (6.0 g) were added to the polymer solution (4.0 g), and the mixture was stirred at room temperature to obtain a methacrylate polymer solution (MP26).
The number average molecular weight of this polymer was 44,000, and the weight average molecular weight was 143,000.

(Example 1)
To the polymer solution (MP2) (3.0 g) obtained in the methacrylate polymer synthesis example 2, the polymer solution (MP4) (7.0 g) obtained in the polyimide polymer synthesis example 4 was added, and D2 (0.06 g) was further added. Was added and stirred at room temperature to obtain a liquid crystal aligning agent (PM1).

(Examples 2 to 24)
Liquid crystal alignment agents (PM2) to (PM24) having compositions shown in Table 2 were obtained in the same manner as in Example 1.

(Comparative Example 1)
D1 (0.06 g) was added to the polymer solution (MP1) (4.0 g) obtained in the methacrylate polymer synthesis example 1, and the mixture was stirred at room temperature to obtain a liquid crystal alignment agent (RPM1).

(Comparative Example 2)
D2 (0.06 g) was added to the polymer solution (MP1) (4.0 g) obtained in the methacrylate polymer synthesis example 1 and stirred at room temperature to obtain a liquid crystal alignment agent (RPM2).

(Comparative Example 3)
D2 (0.06 g) was added to the polymer solution (MP2) (4.0 g) obtained in the methacrylate polymer synthesis example 2, and the mixture was stirred at room temperature to obtain a liquid crystal alignment agent (RPM3).

(Comparative Example 4)
To the polymer solution (MP2) (3.0 g) obtained in the methacrylate polymer synthesis example 2, the polymer solution (MP21) (7.0 g) obtained in the amic acid polymer synthesis example 21 was added, and D2 (0.06 g) was further added. ) And stirred at room temperature to obtain a liquid crystal alignment agent (RPM4).

(Comparative Example 5)
To the polymer solution (MP2) (3.0 g) obtained in the methacrylate polymer synthesis example 2, the polymer solution (MP22) (7.0 g) obtained in the amic acid polymer synthesis example 22 was added, and D2 (0.06 g) was further added. ) And stirred at room temperature to obtain a liquid crystal alignment treatment agent (RPM5).

(Comparative Example 6)
D3 (0.06 g) was added to the polymer solution (MP26) (4.0 g) obtained in the methacrylate polymer synthesis example 26, and the mixture was stirred at room temperature to obtain a liquid crystal alignment treatment agent (RPM6).

<Production of liquid crystal display element>
The liquid crystal aligning agents (PM1) to (PM22) obtained in the examples and the liquid crystal aligning agents (RPM1) to (RPM5) obtained in the comparative example were subjected to pressure filtration with a membrane filter having a pore diameter of 1 μm.
The resulting solution was spin-coated on the ITO surface of a glass substrate with a transparent electrode made of an ITO film, dried on a hot plate at 70 ° C. for 90 seconds, and baked on a hot plate at 200 ° C. for 30 minutes to form a film having a thickness of 100 nm. A liquid crystal alignment film was formed.
Next, the coating film surface was irradiated with 50 mJ / cm ² of 313 nm linearly polarized ultraviolet light having an irradiation intensity of 4.3 mW / cm ² at an angle of 40 ° from the normal direction of the substrate via a polarizing plate, and a substrate with a liquid crystal alignment film was applied. I got Linearly polarized ultraviolet light was prepared by passing ultraviolet light from a high-pressure mercury lamp through a 313 nm bandpass filter and then through a 313 nm polarizing plate.
Two substrates were prepared, and a 4 μm bead spacer was sprayed on the liquid crystal alignment film of one of the substrates, and then a sealant (XN-1500T, manufactured by Mitsui Chemicals, Inc.) was applied. Next, the other substrate was bonded so that the liquid crystal alignment film surfaces faced each other so that the alignment direction was 180 °, and then the sealant was thermally cured at 120 ° C for 90 minutes to produce an empty cell. A liquid crystal (MLC-3022, manufactured by Merck) was injected into the empty cell by a vacuum injection method to obtain a liquid crystal display device.

<Evaluation of applicability>
The liquid crystal display element obtained above was spin-coated on the ITO electrode surface of a glass substrate with an ITO electrode made of an ITO film, dried on a hot plate at 70 ° C. for 90 seconds, and the coated surface was observed. The coating property of the liquid crystal display element was evaluated as “poor” when unevenness or repelling occurred on the coated surface and “good” when uniform without repelling or unevenness. Table 3 shows the evaluation results.

<Evaluation>
(Liquid crystal orientation)
After the liquid crystal display device obtained above was subjected to an isotropic phase treatment at 120 ° C. for 1 hour, cell observation was performed with a polarizing microscope. The case where there was no alignment defect such as light leakage or generation of a domain or the case where uniform driving of liquid crystal was obtained when a voltage was applied to the liquid crystal cell was evaluated as good. Table 4 shows the evaluation results.

(Pretilt angle)
The pretilt angle of the liquid crystal cell of the liquid crystal display element prepared above was measured by the Mueller matrix method using AxoScan manufactured by Axo Metrix. Table 4 shows the evaluation results.

(Evaluation of voltage holding ratio (VHR))
In the evaluation of VHR, a voltage of 1 V was applied to the liquid crystal cell prepared above at a temperature of 60 ° C. for 60 μs, a voltage after 1,667 ms was measured, and a voltage holding ratio was calculated as a voltage holding ratio. .
The voltage holding ratio was measured using a voltage holding ratio measuring device VHR-1 manufactured by Toyo Corporation. Table 4 shows the evaluation results.

(Evaluation of residual DC)
An AC voltage of 6.8 Vpp and a DC voltage of 1 V were applied to the liquid crystal cell prepared above for 48 hours, and a voltage (residual DC) generated in the liquid crystal cell was obtained by a flicker elimination method immediately after the DC voltage was released. This value is an index of the afterimage characteristic, and the case where this value is ± 30 mV or less is regarded as good. Table 4 shows the evaluation results.

(Evaluation of change in tilt angle)
After measuring the pretilt angle, a DC voltage of 15 V was applied to the liquid crystal cell, and after 36 hours, the tilt angle was measured again to calculate how much the tilt angle changed. Table 4 shows the evaluation results.

As can be seen from the results in Table 3, from the comparison between Examples 1 to 24 and Comparative Examples 4 and 5, the blend of the polymethacrylate solution and the polyamic acid solution containing no side-chain diamine has poor applicability, A liquid crystal alignment film having excellent coatability was obtained by blending with a polyimide solution containing no side chain, a polyamic acid containing a side chain, and a polyimide solution.
Further, as can be seen from the results in Table 4, from the comparison between Examples 1 to 24 and Comparative Examples 1 to 6, the polymethacrylate solution was blended with a polyamic acid and a polyimide solution to change the tilt angle, the VHR and the residual. A liquid crystal alignment film excellent in DC was obtained.

液晶 The liquid crystal alignment agent of the present invention and the liquid crystal display device using the liquid crystal alignment film obtained from the liquid crystal alignment agent can be suitably used for a liquid crystal display device requiring durability, such as a vehicle.

Claims

(A) The following formula (pa-1)
(Wherein A is optionally a group selected from fluorine, chlorine and cyano, or an alkoxy group having 1 to 5 carbon atoms, a linear or branched alkyl residue (which may be Pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-thiophenylene, 2,5 Represents furanylene, 1,4- or 2,6-naphthylene or phenylene, R 1 is a single bond, an oxygen atom, —COO— or —OCO—, R 2 is a divalent aromatic group, An alicyclic group, a divalent heterocyclic group or a divalent condensed cyclic group, R 3 is a single bond, an oxygen atom, —COO— or —OCO—, and R 4 has 1 to 40 carbon atoms. Carbon number including linear or branched alkyl or alicyclic group A monovalent organic group having 3 to 40 atoms, D represents an oxygen atom, a sulfur atom or —NR d — (where R d represents a hydrogen atom or an alkyl having 1 to 3 carbon atoms); Is an integer of 0 to 3, and * represents a bonding position.)
A polymer having a photo-alignable group represented by and a thermally crosslinkable group A;
(B) a polymer selected from polyimide and its precursor, which has at least one group selected from a vertical alignment group and a tertiary butoxycarbonyl group, or is at least one of chemically imidized. A polymer; and a solvent;
A liquid crystal aligning agent containing
The liquid crystal alignment agent,
Z1: The polymer (A) further has a thermally crosslinkable group B, and / or Z2: (C) further contains a compound having two or more thermally crosslinkable groups B in a molecule (thermally crosslinkable). The group A and the thermally crosslinkable group B are each independently the same or different, and may be a carboxyl group, an amino group, an alkoxymethylamide group, a hydroxymethylamide group, a hydroxyl group, an epoxy site-containing group, an oxetanyl group , A group selected from the group consisting of a thiiranyl group, an isocyanate group, and a blocked isocyanate group, which is selected so that a heat-crosslinkable group A and a heat-crosslinkable group B are cross-linked by heat.) Agent.
The liquid crystal aligning agent according to claim 1, wherein the component (B) is a polymer having a vertical alignment group.
The liquid crystal aligning agent according to claim 1, wherein the component (B) is a polymer having a tertiary butoxycarbonyl group.
The liquid crystal aligning agent according to claim 1, wherein the component (B) is a chemically imidized polymer.
(4) A liquid crystal alignment film formed using the liquid crystal alignment agent according to any one of (1) to (4).
A step of applying the liquid crystal aligning agent according to any one of claims 1 to 4 on a substrate to form a coating film, and the coating film is not in contact with the liquid crystal layer or is not in contact with the liquid crystal layer. Irradiating the coating film with light in a contact state.
A liquid crystal display device comprising the liquid crystal alignment film according to claim 5 or the liquid crystal alignment film obtained by the method according to claim 6.