TWI805572B - Liquid crystal alignment agent, liquid crystal alignment film and liquid crystal display element - Google Patents

Abstract

。The present invention provides a liquid crystal alignment film and a liquid crystal alignment agent with good liquid crystal alignment, excellent pretilt angle performance and high reliability even if the firing time is shortened. The present invention provides a liquid crystal alignment agent, which is a liquid crystal alignment agent containing (A) component: a polymer having the following (A-1) and (A-2) structures; and a solvent, and the above polymer may further have ( A-3) has a group selected from oxetanyl group, oxirane group, the group represented by the following formula (3), the group represented by the following formula (4), the group represented by the following formula (5) and/or the aforementioned liquid crystal alignment agent further has a (B) component other than the above-mentioned (A) component, and the (B) component contains 2 in the molecule More than one compound selected from the group consisting of epoxy group, epithioethylene group, hydroxyalkylamide group, and benzyl alcohol group; (A-1) has a group selected from carboxyl group, amino group and The structure of the hydroxyl group and at least one functional group; (A-2) the structure represented by the following formula (pa-1) (the symbols in the formula are as defined in the specification),

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Description

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

The present invention relates to a liquid crystal alignment agent, a liquid crystal alignment film obtained therefrom, and a liquid crystal display element provided with the obtained liquid crystal alignment film. More specifically, it relates to a liquid crystal alignment agent that can be applied to a liquid crystal alignment film. Even if the liquid crystal alignment film is fired at a low temperature and the firing time is shortened, the liquid crystal alignment is good and the pretilt angle Display performance is also excellent and high reliability can be obtained, as well as a liquid crystal display element excellent in display quality.

In the liquid crystal display element, the liquid crystal alignment film plays the role of aligning the liquid crystal in a certain direction. The main liquid crystal alignment film used in the industry today is made by the following method: polyamic acid (also known as polyamic acid), polyamic acid ester, or polyimide A polyimide-based liquid crystal alignment agent made of an amine solution is applied to a substrate and formed into a film. In addition, if the liquid crystal is aligned parallel or obliquely with respect to the substrate surface, surface stretching treatment by rubbing is further performed after film formation.

On the other hand, when aligning the liquid crystal vertically with respect to the substrate (also known as the vertical alignment (VA) method), a long-chain alkyl group, a cyclic group, or a combination of a cyclic group and an alkyl group (refer to For example, a liquid crystal alignment film in which hydrophore groups such as patent document 1) and a steroid skeleton (refer to eg patent document 2) are introduced into side chains of polyimide. In this case, when applying a voltage between the substrates to incline the liquid crystal molecules in a direction parallel to the substrates, it is necessary to incline the liquid crystal molecules in a direction inward from the normal direction of the substrates. As such means, for example, proposals include: a method of providing protrusions on the substrate; a method of providing slits in the display electrodes; and by rubbing, the liquid crystal molecules are only slightly directed toward the inside of the substrate from the normal direction of the substrate. The method of tilting (making it pre-tilt); furthermore, adding a photopolymerizable compound to the liquid crystal composition in advance, and using it together with a vertical alignment film such as polyimide, and irradiating ultraviolet rays while applying a voltage to the liquid crystal cell, by This is a method of pretilting liquid crystals (see, for example, Patent Document 3) and the like.

In recent years, there are also proposals to form protrusions or slits in the aspect of liquid crystal alignment control in the VA method, and a method of using anisotropic photochemical reaction (photoalignment method) by polarized ultraviolet irradiation as a substitute for PSA technology. That is, it is known that a polarized ultraviolet ray is irradiated to a polyimide film having photoreactive vertical alignment to impart alignment control capability and pretilt angle expressability, thereby uniformly controlling the inclination of liquid crystal molecules when a voltage is applied. direction (refer to Patent Document 4). Also in this case, the same as the conventional alignment film, a polyimide-based liquid crystal alignment film excellent in durability and suitable for the control of the liquid crystal pretilt angle is used.

On the other hand, among the solvents of liquid crystal alignment treatment agents using polyimide polymers, N-methyl-2-pyrrolidone is used because the solvent solubility of these polyimide polymers is low. (Also known as NMP) and other highly polar solvents. These highly polar solvents have high boiling points, for example, NMP has a boiling point of 200° C. or higher. Therefore, in order to use a liquid crystal alignment treatment agent made of NMP as a solvent to produce a liquid crystal alignment film, in order to eliminate the remaining NMP in the liquid crystal alignment film, it is necessary to perform firing at a high temperature near the boiling point of NMP (about 200°C). .

In this regard, if a thinner, lighter but less heat-resistant plastic substrate is used as the substrate of the liquid crystal display element, the firing must be carried out at a lower temperature when making the liquid crystal alignment film. Similarly, by making this calcination temperature low, reduction of the energy cost in manufacture of a liquid crystal display element can also be acquired.

When firing at a low temperature, there is a problem that the alignment film material must be cured when it is not sufficiently cured, and it is difficult to obtain a highly reliable liquid crystal display element (see, for example, Patent Document 5). [Prior Art Document] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open No. 3-179323 [Patent Document 2] Japanese Patent Laid-Open No. 4-281427 [Patent Document 3] Japanese Patent No. 4504626 [Patent Document 4] Japanese Patent No. 4995267 [Patent Document 3] Document 5] Japanese Patent Application Laid-Open No. 7-209633

[Problem to be Solved by the Invention]

As a result of the inventor's examination, it is known that lowering the firing temperature and shortening the firing time to produce a liquid crystal alignment film will significantly impair the liquid crystal alignment in addition to the above. The subject of the present invention is a liquid crystal alignment film and a liquid crystal alignment agent that have good liquid crystal alignment, excellent pretilt angle display performance, and high reliability even if the firing time is shortened. [Means to solve the problem]

The inventors of the present invention have discovered the invention having the following <X> as the gist. <X> A liquid crystal alignment agent containing (A) component: a polymer having the following (A-1) and (A-2) structures; and a liquid crystal alignment agent of a solvent. The above-mentioned polymer may further have (A -3) It has a group selected from oxetanyl group (oxetanyl group), oxiranyl group (oxiranyl group), the group represented by the following formula (3), the group represented by the following formula (4), the following The structure of the group represented by the above formula (5) and at least one functional group of the thiirane group (hereinafter also referred to as "thermally crosslinkable group"); and/or the aforementioned liquid crystal alignment agent further It has (B) component other than the above-mentioned (A) component, and the (B) component contains two or more groups selected from the group consisting of epoxy group, epithiol group, hydroxyalkylamide group, and benzyl alcohol group in the molecule. Compounds that are the basis of groups.

(A-1) A structure having at least one functional group selected from a carboxyl group, an amine group, and a hydroxyl group in a molecule (hereinafter also referred to as "polar group"). (A-2) A structure represented by the following formula (pa-1) (hereinafter also referred to as "photoalignment group").

In the formula, A means that it is optionally substituted by a group selected from fluorine, chlorine, and cyano, or by an alkoxy group with 1 to 5 carbons, a linear or branched alkyl residue (this is an optional Pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-thienyl (2,5-thiophenylene) substituted by 1 cyano group or more than 1 halogen atom) group), 2,5-furylene group (2,5-furylene group), 1,4- or 2,6-naphthyl or phenylene, _R1 is a single bond, oxygen atom, -COO- or - OCO-, _R2 is a divalent aromatic group, a divalent alicyclic group, a divalent heterocyclic group or a divalent condensed ring group, _R3 is a single bond, an oxygen atom, -COO- or -OCO-, _R4 is a linear or branched alkyl group with 1 to 40 carbons or a monovalent organic group with 3 to 40 carbons containing an alicyclic group, and D represents an oxygen atom, a sulfur atom or - NR _d - (herein, R _d represents a hydrogen atom or an alkyl group with 1 to 3 carbons), a is an integer of 0 to 3, and * represents a bonding position in the formula.

[發明的效果]

[Effect of the invention]

According to the present invention, even if the firing time is shortened, a liquid crystal alignment film and a liquid crystal alignment agent having good liquid crystal alignment, excellent pretilt angle display performance, and high reliability can be provided. Also, the liquid crystal display element manufactured by the method of the present invention has excellent display characteristics.

[Best Mode for Carrying Out the Invention]

The liquid crystal alignment agent of the present invention contains (A) component: have the polymer of following (A-1) and (A-2) structure; And Solvent. Also, the liquid crystal alignment agent of the present invention further has the following first state; and/or the second state. That is, in the liquid crystal alignment agent of the first aspect of the present invention, the above-mentioned polymer further has (A-3) a group selected from the group consisting of oxetanyl group, oxirane group, and the above-mentioned formula (3). . The structure of at least one functional group of the group represented by the above formula (4), the group represented by the above formula (5), and the epithio group (hereinafter also referred to as "thermally crosslinkable group"). The liquid crystal alignment agent of the second aspect of the present invention further has a (B) component other than the above-mentioned (A) component, and the (B) component contains two or more components selected from the group consisting of epoxy group and epithionine in the molecule. Compounds based on groups of alkyl groups, hydroxyalkylamide groups, and benzyl alcohol groups. The (B) component is a compound containing two or more epoxy groups or epithioethyl groups in the molecule, or, the (B) component is a compound containing two or more epoxy groups selected from the group consisting of hydroxyalkylamide groups, And benzyl alcohol based compounds. Here, the so-called "two or more in the molecule" means, for example, containing two or more epoxy groups (more than two identical groups) in the molecule, and, for example, epoxy groups and epithionyl groups Alkyl-like combinations, even if they are heterogeneous, include the case where the molecule contains two or more groups selected from the group consisting of epoxy group, epithioethylene group, hydroxyalkylamide group, and benzyl alcohol group in the meaning. "Two or more in the molecule" means preferably two or more groups of the same kind, preferably contained in the molecule.

The liquid crystal alignment agent of the first aspect of the present invention contains a polymer having the structure (A-1) to (A-3) (hereinafter also referred to as "the first specific polymer") and a solvent. In addition, the liquid crystal alignment agent of the second aspect of the present invention contains polymers having the structures (A-1) and (A-2) (hereinafter also referred to as "second specific polymers"), (B ) ingredients and solvents. Here, the three structures of the first specific polymer or the two structures of the second specific polymer can all become the structures of the side chains in the polymer, so they can also be called "side chains" as needed. Hereinafter, each constituent element of the present invention will be described in detail, especially the first aspect and the second aspect of the present invention.

<(A) Component: First Specific Polymer> The first specific polymer of the present invention is represented by the following formula (I).

In the formula, S _a , S _b , and S _c represent independent interval units, I _a1 is synonymous with the definition in the formula (a-1-m) described later, and I _b is the aforementioned formula (pa-1) Represented base, I _c represents to have and is selected from the base represented by oxetanyl group, oxirane group, aforementioned formula (3), the base represented by aforementioned formula (4), aforementioned formula (5) A monovalent organic group that is at least one functional group of the group represented and the thioethylene group. M _a , M _c , M _d , _Me , r ¹ , r ² are defined in formula (a-1-m), formula (b-1-m) and formula (c-1-m) described later for the same.

Moreover, x, y, and z are not specifically limited, For example, x, y, and z can each independently be set as the value of 0.01 or more and 0.89 or less. Still, the formulas (I)~(II) mean that each side chain exists in the ratio of x, y, z, but it does not mean that each side chain in the polymer is block copolymerized thing.

<(A) Component: Second Specific Polymer> The second specific polymer used in the second aspect of the present invention is represented by the following formula (I').

In the formula (I'), S _a , S _b , I _a1 , I _b , Ma , M _c , M _d , r ¹ , and r ² have the same meaning as _those mentioned above. Moreover, in formula (I'), x and y are not specifically limited, For example, x and y can each independently set the value of 0.05 or more and 0.95 or less. Furthermore, the formula (I') means that each side chain exists in the ratio of x and y, but it does not mean that each side chain in the polymer is block-formed to form a block copolymer.

The first specific polymer and the second specific polymer contained in the liquid crystal alignment agent of the present invention have high sensitivity to light, so they can exhibit alignment control even under low-exposure polarized ultraviolet radiation. The first specific polymer can be cross-linked in the first specific polymer even if the firing time of the liquid crystal alignment agent is shortened by the reaction of the above-mentioned thermal cross-linkable group with the amine group, hydroxyl group or carboxyl group. joint reaction. Therefore, when the photoalignment site of the first specific polymer exhibits anisotropy due to photoreaction, it becomes easy to remain (memory/memory) anisotropy on the liquid crystal alignment film, thereby improving the liquid crystal alignment, And can show the pretilt angle of the liquid crystal. The amine group, carboxyl group, and hydroxyl group of the first specific polymer and the second specific polymer are selected from the epoxy group, thioethyl group, hydroxyalkylamide group, Even if the firing time of the liquid crystal alignment agent is shortened, the cross-linking reaction can be carried out in the first specific polymer and the second specific polymer. Therefore, when the photoalignment site of the first specific polymer and the second specific polymer exhibits anisotropy due to photoreaction, it becomes easy to remain (memory) the anisotropy on the liquid crystal alignment film, thereby improving the Liquid crystal alignment, and can show the pre-tilt angle of liquid crystal.

<(A-1) Structure having a polar group in the molecule> The first specific polymer and the second specific polymer contained in the liquid crystal alignment agent of the present invention have The structure of a polar group (that is, at least one functional group selected from a carboxyl group, an amine group, and a hydroxyl group). This structure is because the liquid crystal alignment agent obtained from the first specific polymer and the second specific polymer of the present invention can undergo a crosslinking reaction in the specific polymer even if the firing time is shortened, thereby improving The liquid crystal alignment property of the obtained liquid crystal alignment film can exhibit the pretilt angle of the liquid crystal at the same time.

In the present invention, the structure having a polar group in the molecule can be represented by, for example, the following formula (a-1). Moreover, although the structure derived from the monomer represented by following formula (a-1-m) is mentioned as this structure system, it is not limited to this.

In the formula, I _a1 is a monovalent organic group selected from a carboxyl group, a hydroxyl group, a group having at least one partial structure of the following formula (a2), or a primary amino group. However, the following formula (a2) represents a group other than a primary amino group, and r ¹ is 1 or 2. In the formula, * represents a bonding portion.

Also, S _a represents a single bond or a divalent linking group. In I _a1 , the group having the partial structure of the above formula (a2) includes, for example, a 5- or 6-membered nitrogen-containing heterocyclic ring, such as piperidine, morpheline, and the like. These respective 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. Preferable examples of I _a1 include monovalent organic groups selected from carboxyl groups and hydroxyl groups.

M _a represents the first polymerizable group. Examples of the first polymerizable group include the following formulas (M _a -1) to (M _a -2), α-methylene-γ-butyrolactone, maleimide, norcamphene, and The free radical polymerizable group of the derivative, siloxane. Preferably, formulas (M _a -1) to (M _a -2) and α-methylene-γ-butyrolactone maleimide are suitable. In the formula, R ₁ represents a hydrogen atom or an alkyl group having 1 to 5 carbons, and * represents a bonding portion.

As the divalent linking group in S _a of the aforementioned formula (a-1-m), for example, an alkanediyl group with 1 to 10 carbons (preferably 1 to 6), alkanediyl with 6 to 20 carbons (preferably 6~14) aryl, (*A)-CONH-R ₆ -(*B) group, (*A)-COO-R ₇ -(*B) group, etc. Here, R _{and R} independently represent a single bond, or an alkanediyl group with 1 to 12 carbons (preferably 1 to 6), or an alkanediyl group with 6 to 20 carbons (preferably 6 to 14). Any carbon-carbon bond of an aryl group, an alkyleneoxy aryl group, and an alkanediyl group may have an -O-bond, (*A) represents a bonded portion that is bonded to a carbon atom having an unsaturated bond, ( *B) represents a bonded part to I _a1 . Examples of the alkanediyl group include methylene, ethylidene, ethane-1,1-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-1,3- Diyl, propane-2,2-diyl, butane-1,2-diyl, butane-1,3-diyl, butane-1,4-diyl, pentane-1,4-diyl base, pentane-1,5-diyl, hexane-1,5-diyl, hexane-1,6-diyl, etc. Moreover, as an aryl group, a phenylene group, a naphthylene group, a biphenylene group, an anthracenyl group etc. are mentioned, for example. Examples of the alkoxyarylylene group include ethoxyphenylene, hexyloxyphenylene, hexyloxybiphenylene and the like. Among them, as the divalent linking group in S _a , it is preferably an alkanediyl group with 1 to 10 carbons (preferably 1 to 6) and an alkanediyl group with 6 to 20 carbons (preferably 6 to 14). Group, (*A)-COO-R ₇ -(*B) group, R ₇ is preferably an alkanediyl group having 2 to 6 carbon atoms.

Specific examples of the above formula (a-1-m) having a carboxyl group include (meth)acrylic acid, carboxyethyl (meth)acrylate, carboxypentyl (meth)acrylate, crotonic acid, and methacrylic acid. , α-ethacrylic acid, β-ethacrylic acid, β-propyl acrylic acid, β-isopropyl acrylic acid, itaconic acid, fumaric acid, vinyl benzoic acid, etc. Moreover, as a specific example of the said formula (a-1-m) which has an amino group, t-butylamino ethyl (meth)acrylate etc. are mentioned. Specific examples of the above formula (a-1-m) having a hydroxyl group include 2-hydroxyethyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-Hydroxypropyl, (meth)acrylate-4-hydroxybutyl, (meth)acrylate-6-hydroxyhexyl, (meth)acrylate-8-hydroxyoctyl, (meth)acrylate-10- Hydroxyalkyl (meth)acrylates such as hydroxydecyl, 12-hydroxylauryl (meth)acrylate; hydroxyethyl (meth)acrylamide, other acrylic acid (4-hydroxymethylcyclohexyl) Methyl ester, N-hydroxymethyl(meth)acrylamide, N-hydroxy(meth)acrylamide, etc. Specific examples of the above-mentioned formula (a-1-m) having a partial structure of the above-mentioned formula (a2) include 2,2,6,6-tetramethyl-4-piperidinyl methacrylate wait.

The site having a polar group contained in the polymer of the present invention may be used alone or in combination of two or more sites. Also, the portion having a polar group contained in the molecule is defined as 5 to 94 mol%, 20 to 94 mol%, or 20 to 88 mol%, or 25 to 80 mol% of the first specific polymer (component (A)). better. Or, contained in the molecule at a ratio of 5 to 95 mol%, or 20 to 90 mol%, or 30 to 85 mol%, 20 to 80 mol%, or 50 to 85 mol% of the second specific polymer (component (A)) A site having a polar group is preferable.

<(A-2) Structure with photoalignment> The first specific polymer and the second specific polymer contained in the liquid crystal alignment agent of the present invention have the above-mentioned formula in the molecule (preferably in the side chain) (pa-1) shows the structure of the light alignment. By setting the structure of the photo-alignment site as described above, even when exposed to external stress such as heat, the vertical alignment control ability can be stably maintained for a long period of time. Moreover, since the sensitivity to light is high, it can exhibit alignment control ability even in low-exposure polarized ultraviolet irradiation, which is preferable from the viewpoint of simplifying the manufacturing steps of the liquid crystal alignment film.

In the present invention, the site having the photo-alignment property represented by the formula (pa-1) in the molecule can be represented by the following formula (b-1), for example. Moreover, although the structure derived from the monomer represented by following formula (b-1-m) is mentioned as this part, it is not limited to this. In the formula, I _b is a monovalent organic group represented by the following formula (pa-1).

In formula (pa-1), A means that it is substituted by a group selected from fluorine, chlorine, and cyano, or by an alkoxy group with 1 to 5 carbons, a linear or branched alkyl residue (This is pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-thienyl, 2,5-furyl, 1,4- or 2,6-naphthyl or phenylene, R ₁ is a single bond, oxygen atom, -COO- or -OCO-, R ₂ is a divalent aromatic base, divalent alicyclic group, divalent heterocyclic group or divalent condensed ring group, R ₃ is a single bond, oxygen atom, -COO- or -OCO-, R ₄ is a carbon number 1~ 40 straight-chain or branched-chain alkyl or a monovalent organic group with 3 to 40 carbon atoms containing an alicyclic group, D represents an oxygen atom, a sulfur atom or -NR _d - (herein, R _d represents A hydrogen atom or an alkyl group with 1 to 3 carbons), a is an integer of 0 to 3, and * is the bonding position in the table.

In the above-mentioned formula (b-1) or (b-1-m), S _b represents a spacer unit, and the bonding part (ligand) on the left side of S _b represents any bonded to the first specific polymer through a spacer. and the main chain of the second specific polymer. S _b can be represented by, for example, the structure of the following formula (Sp).

In formula (Sp), the bond on the left of W ₁ represents the bond to M _d , the bond on the right of W ₃ represents the bond to I _b , and W ₁ , W ₂ and W ₃ represent independently Single bond, divalent heterocyclic ring, -(CH ₂ ) _n - (where n represents 1 to 20), -OCH ₂ -, -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 non-adjacent CH ₂ groups in these substituents Can be independently represented by -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- (formula Among them, R is independently represented by hydrogen or a linear or branched alkyl group with 1 to 5 carbon atoms), and _A1 and _A2 are independently selected from single bonds, divalent alkyl groups, divalent An aromatic group, a divalent alicyclic group, or a divalent heterocyclic group, each group may be unsubstituted or one or more hydrogen atoms may be replaced by a fluorine atom, chlorine atom, cyano group, or methyl group Or substituted by methoxy.

In formula (b-1-m), M _c represents a second polymerizable group. Examples of the second polymerizable group include (meth)acrylate, fumarate, maleate, α-methylene-γ-butyrolactone, styrene, vinyl, maleyl Amines, norcamphenes, (meth)acrylamides and radically polymerizable groups of derivatives thereof, and siloxanes. Preferred are (meth)acrylate, α-methylene-γ-butyrolactone, styrene, vinyl, maleimide, and acrylamide.

r ² is an integer satisfying 1≦r ² ≦3.

In formula (b-1-m), M _d is selected from a single bond, (r ² +1) valent heterocyclic ring, straight-chain or branched-chain alkyl group with 1 to 10 carbons, (r ² +1 ) valent aromatic group, (r ² +1) valent alicyclic group, the respective groups can be unsubstituted or more than one hydrogen atom can be replaced by fluorine atom, chlorine atom, cyano group, methyl group or substituted by methoxy.

Examples of the aromatic groups in A ₁ , A _{2 ,} and M _d include aromatic hydrocarbon groups having 6 to 18 carbon atoms such as benzene, biphenyl, and naphthalene. Examples of the alicyclic group in A ₁ , A _{2 ,} and M _d include alicyclic hydrocarbon groups having 6 to 12 carbon atoms such as cyclohexane and bicyclohexane. Examples of heterocyclic rings in A ₁ , A _{2 ,} and M _d include nitrogen-containing heterocyclic rings such as pyridine, piperidine, and piperazine. Examples of the alkyl group in A ₁ and A ₂ include straight-chain or branched-chain alkyl groups having 1 to 10 carbon atoms.

From the viewpoint of exhibiting good vertical alignment control performance and a stable pretilt angle, the group represented by (pa-1) above, or the following (pa-1- a) The basis represented. Moreover, although the structure derived from the monomer represented by following formula (pa-1-ma) is mentioned as this site|part, it is not limited to this.

In formula (pa-1-a) or (pa-1-ma), M _c , M _d , and S _b are synonymous with the above. Also, 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 _is a linear or branched alkyl group having 1 to 40 carbon atoms or a monovalent organic group having 3 to 40 carbon atoms containing an alicyclic group. R ₅ is an alkyl group with 1 to 3 carbons, an alkoxy group with 1 to 3 carbons, a fluorine atom or a cyano group, preferably a methyl group, a methoxy group or a fluorine atom. a is an integer from 0 to 3, and b is an integer from 0 to 4.

In the formula (pa-1-a) or (pa-1-ma), as a straight chain or branched chain alkylene group with 1 to 10 carbons of S _b , a straight chain or branched chain with 1 to 8 carbons The alkylene group is preferred, such as methylene, ethylene, n-propylidene, n-butylene, t-butylene, n-pentyl, n-hexyl, n - heptyl, n-octyl. The divalent aromatic group of _Sb includes, for example, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene, 2,3, 5,6-tetrafluoro-1,4-phenylene, etc.

In the formula (pa-1-a) or (pa-1-ma), as the divalent alicyclic group of S _b , examples include trans-1,4-cyclohexyl, trans-trans-1,4 - extended bicyclohexyl and the like. The divalent heterocyclic group of _Sb includes, for example, 1,4-pyridyl, 2,5-pyridyl, 1,4-furyl, 1,4-piperazinyl, 1,4 - piperidinyl etc. S _b is preferably an alkylene group having 1 to 8 carbons, more preferably an alkylene group having 1 to 6 carbons, more preferably an alkylene group having 1 to 4 carbons.

The divalent aromatic group of _R2 includes, for example, 1,4-phenylene, 2-fluoro-1,4-phenylene, 3-fluoro-1,4-phenylene, 2,3, 5,6-tetrafluoro-1,4-phenylene, naphthylene, etc. The divalent alicyclic group of R ₂ includes, for example, trans-1,4-cyclohexylene, trans-trans-1,4-bicyclohexylene, and the like. As the divalent heterocyclic group of _R2 , for example, 1,4-pyridyl, 2,5-pyridyl, 1,4-furyl, 1,4-piperazinyl, 1,4 - piperidinyl etc. R ₂ is preferably 1,4-phenylene, trans-1,4-cyclohexyl, trans-trans-1,4-bicyclohexyl.

As a straight chain or branched chain alkyl group with 1 to 40 carbons as R, for example, a straight chain or branched chain alkyl group with 1 to 20 carbons, a part or all of the hydrogen atoms of the alkyl group can be covered with _fluorine atoms replaced. Examples of the alkyl group include methyl, ethyl, n-propyl, n-butyl, t-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl base, n-nonyl, n-decyl, n-lauryl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl base, n-heptadecyl, n-octadecyl, n-nonadecyl, n-eicosyl, 4,4,4-trifluorobutyl, 4,4,5,5,5 -Pentafluoropentyl, 4,4,5,5,6,6,6-heptafluorohexyl, 3,3,4,4,5,5,5-heptafluoropentyl, 2,2,2-tri Fluoroethyl, 2,2,3,3,3-pentafluoropropyl, 2-(perfluorobutyl)ethyl, 2-(perfluorooctyl)ethyl, 2-(perfluorodecyl)ethyl Base etc.

As R ₄ , a monovalent organic group having 3 to 40 carbon atoms containing an alicyclic group includes, for example, a cholesterol group, a cholyl alcohol group, an adamantyl group, the following formula (Alc-1) or (Alc-2) (In the formula, _R7 is a hydrogen atom, a fluorine atom, or an alkyl group with 1 to 20 carbon atoms that can be substituted by a fluorine atom, and * represents the bonding position).

Examples of the monomer represented by the formula (pa-1-ma) include structures represented by the formulas (paa-1-ma1) to (paa-1-ma18), but are not limited thereto. Still, in the formula, "E" means the E-body, and "t" means the cyclohexyl is inversion.

The photoreactive moiety contained in the polymer of the present invention may be used alone or in combination of two or more moieties. The photoreactive part is defined as a proportion of 5-94mol%, 10-80mol%, or 15-70mol%, 10-50mol%, or 15-50mol% of the first specific polymer (component (A)). good. Or, the ratio of 5~95mol%, 10~80mol%, or 15~70mol%, or 15~60mol%, or 15~50mol% of the second specific polymer (component (A)) contains photoreactive The location is better.

<(A-3) Portions having thermally crosslinkable groups> The first specific polymer contained in the liquid crystal alignment agent of the present invention has "parts having thermally crosslinkable groups", that is, has optional From the oxetanyl group (1,2-epoxy group structure), the oxiranyl group (1,3-epoxy group structure), the group represented by the following formula (3), the following formula (4 ), the group represented by the following formula (5), and the site of at least one functional group of the thioethyl group. In other words, the first specific polymer is equipped with a group selected from the group represented by oxetanyl group, oxirane group, the following formula (3), and the group represented by the following formula (4) in the side chain. The site of at least one functional group of the group represented by the following formula (5) and the thioethyl group. In the formulas (3) to (5), * represents a bonding part.

The portion having a thermally crosslinkable group in (A-3) above can form a crosslinking reaction with the amine group, hydroxyl group or carboxyl group of the above polar group, even if the firing time of the liquid crystal alignment agent is shortened, it can also By stabilizing the liquid crystal alignment at the site having photoalignment in (A-2) above, a liquid crystal alignment film excellent in pretilt angle development can be obtained.

In the present invention, the portion having a heat-crosslinkable group can be represented by, for example, the following formula (c-1). Moreover, the structure derived from the monomer represented by following formula (c-1-m) is mentioned as this part.

In formula (c-1) or (c-1-m), _Ic is selected from the group represented by oxetanyl group, oxirane group, above-mentioned formula (3), above-mentioned formula ( 4) A monovalent organic group of the group represented by, the group represented by the above formula (5), and the thioethyl group. S _c represents a single bond or a divalent linking group. Also, in the formula (c-1-m), M _e represents the third polymerizable group. Examples of the third polymerizable group include the following formulas (M _c -1) to (M _c -2), α-methylene-γ-butyrolactone, maleimide, norcamphene, and The free radical polymerizable group of the derivative, siloxane.

In the formulas (M _c -1) to (M _c -2), Rc represents a hydrogen atom or an alkyl group having 1 to 5 carbons, and * represents a bonding position. As M _e , formulas (M _c -1) to (M _c -2), α-methylene-γ-butyrolactone maleimide are preferred.

As the divalent linking group in S _c of the aforementioned formula (c-1-m), for example, alkanediyl with 1 to 10 carbons (preferably 1 to 6), alkanediyl with 6 to 20 carbons (preferably 6~14) aryl, (*A)-CONH-R ₆ -(*B) group, (*A)-COO-R ₇ -(*B) group, etc. Here, R ₆ and R ₇ are independent of each other representing a single bond, or an alkanediyl group with 1 to 12 carbons (preferably 1 to 6), or an aromatic group with 6 to 20 carbons (preferably 6 to 14). Any carbon-carbon bond of alkanediyl group, alkyleneoxyarylylene group, and alkanediyl group may have -O-bond or -S-bond, (*A) represents a bond with a carbon atom having an unsaturated bond The junction part, (*B) represents the junction part which bonds with I _a1 . Examples of the alkanediyl group include methylene, ethylidene, ethane-1,1-diyl, propane-1,1-diyl, propane-1,2-diyl, propane-1,3- Diyl, propane-2,2-diyl, butane-1,2-diyl, butane-1,3-diyl, butane-1,4-diyl, pentane-1,4-diyl base, pentane-1,5-diyl, hexane-1,5-diyl, hexane-1,6-diyl, etc. Moreover, as an aryl group, a phenylene group, a naphthylene group, a biphenylene group, an anthracenyl group etc. are mentioned, for example. Examples of the alkoxyarylylene group include ethoxyphenylene, hexyloxyphenylene, hexyloxybiphenylene and the like. Among them, as the divalent linking group in S _a , it is preferably an alkanediyl group with 1 to 10 carbons (preferably 1 to 6) and an alkanediyl group with 6 to 20 carbons (preferably 6 to 14). Group, (*A)-COO-R ₇ -(*B) group, R ₇ is preferably an alkanediyl group having 2 to 6 carbon atoms. One or more hydrogen atoms in each group may be substituted by a fluorine atom, a chlorine atom, a cyano group, a methyl group or a methoxy group.

Specific examples of the formula (c-1-m) having an oxirane group include allyl glycidyl ether, glycidyl acrylate, glycidyl methacrylate, 2-methyl glycidyl methacrylate, etc. Glyceryl esters, α-glycidyl ethacrylate, α-n-propyl glycidyl acrylate, α-n-butyl glycidyl acrylate, 3,4-epoxybutyl acrylate, methacrylic acid 3, 4-epoxybutyl acrylate, 6,7-epoxyheptyl acrylate, 6,7-epoxyheptyl methacrylate, 6,7-epoxyheptyl α-ethacrylate, o-ethylene benzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl ether, 3,4-epoxycyclohexylmethyl methacrylate, 3-vinyl-7-oxy Heterobicyclo[4.1.0]heptane, 1,2-epoxy-5-hexene, 1,7-octadiene monoepoxide, etc. Among them, glycidyl methacrylate, 2-methylglycidyl methacrylate, methacrylic acid-6,7 - Epoxyheptyl ether, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl ether, 3,4-epoxycyclohexyl methacrylate is better.

Specific examples of formula (c-1-m) having an oxetanyl group include 3-(acryloxymethyl)oxetane, 3-(acryloxymethyl) -2-methyloxetane, 3-(acryloxymethyl)-3-ethyloxetane, 3-(acryloxymethyl)-2-trifluoromethyloxy Heteretane, 3-(acryloxymethyl)-2-pentafluoroethyloxetane, 3-(acryloxymethyl)-2-phenyloxetane, 3 -(acryloxymethyl)-2,2-difluorooxetane, 3-(acryloxymethyl)-2,2,4-trifluorooxetane, 3-( Acryloxymethyl)-2,2,4,4-tetrafluorooxetane, 3-(2-acryloxyethyl)oxetane, 3-(2-acryloxy ethyl)-2-ethyloxetane, 3-(2-acryloxyethyl)-3-ethyloxetane, 3-(2-acryloxyethyl) -2-Trifluoromethyloxetane, 3-(2-acryloxyethyl)-2-pentafluoroethyloxetane, 3-(2-acryloxyethyl) -2-Phenyloxetane, 3-(2-acryloxyethyl)-2,2-difluorooxetane, 3-(2-acryloxyethyl)-2 , Acrylates of 2,4-trifluorooxetane, 3-(2-acryloxyethyl)-2,2,4,4-tetraoxetane, etc.; 3-(methyl Acryloxymethyl)oxetane, 3-(methacryloxymethyl)-2-methyloxetane, 3-(methacryloxymethyl)-3 -Ethyloxetane, 3-(methacryloxymethyl)-2-trifluoromethyloxetane, 3-(methacryloxymethyl)-2-penta Fluoroethyloxetane, 3-(methacryloxymethyl)-2-phenyloxetane, 3-(methacryloxymethyl)-2,2-di Fluoroxetane, 3-(methacryloxymethyl)-2,2,4-trifluorooxetane, 3-(methacryloxymethyl)-2,2 ,4,4-tetrafluorooxetane, 3-(2-methacryloxyethyl)oxetane, 3-(2-methacryloxyethyl)-2- Ethyloxetane, 3-(2-methacryloxyethyl)-3-ethyloxetane, 3-(2-methacryloxyethyl)-2- Trifluoromethyloxetane, 3-(2-methacryloxyethyl)-2-pentafluoroethyloxetane, 3-(2-methacryloxyethyl )-2-phenyloxetane, 3-(2-methacryloxyethyl)-2,2-difluorooxetane, 3-(2-methacryloxy ethyl)-2,2,4-trifluorooxetane, 3-(2-methacryloxyethyl)-2,2,4,4-tetraoxetane, etc. acrylates, etc. As specific examples of the formula (c-1-m) having an epithiol group, compounds represented by the following formula (S),

In the formula, X represents O(CH ₂ ) _n , S(CH ₂ ) _n , or (CH ₂ ) _n , n represents an integer from 0 to 6, and Y represents acryl, methacryl, allyl base, or vinyl), or 2,3-epithiopropyl acrylate or methacrylate, and 2- or 3- or 4-(β-epithiopropylthiomethyl)styrene, 2- or 3- or 4-(β-epithiopropyloxymethyl)styrene, 2- or 3- or 4-(β-epithiopropylthio)styrene, 2- or 3- or 4- (β-epithiopropyloxy)styrene and the like.

The portion having a thermally crosslinkable group contained in the polymer of the present invention may be used alone or in combination of two or more types. The introduction amount of the portion having a heat-crosslinkable group is 1 to 40 mol%, or 1 to 30 mol%, or 5 to 30 mol%, or 2 to 30 mol%, or 5 mol% of the first specific polymer (component (A)). ~25mol% is better.

<(B) A compound containing two or more groups selected from the group consisting of epoxy group, thioethyl group, hydroxyalkylamide group, and benzyl alcohol group in the molecule> The second aspect of the present invention The (B) component used in the liquid crystal alignment agent has two or more groups selected from epoxy groups, epithiol groups, hydroxyalkylamide groups, and benzyl alcohol groups in the molecule. base compound. By adopting such a constitution, the epoxy group or the thioethylene group can partially exist in the upper layer part of the liquid crystal alignment film, and promote the combination with the above-mentioned first specific polymer and the second specific polymer. The cross-linking reaction of the amino group or carboxyl group of the polar group in (A-1) increases the cross-linking density of the membrane surface layer components. Therefore, the anisotropy caused by the photoreaction of (A-2) above becomes easy to remain (memory) on the film, the liquid crystal alignment can be stabilized, and the liquid crystal alignment and pretilt angle development performance can be obtained. Liquid crystal alignment film.

The compound having two or more epoxy groups or thiol groups in the molecule is not particularly limited as long as it has two or more epoxy groups or thiol groups at the molecular terminal. Examples of compounds having two or more epoxy groups at molecular terminals include epoxy compounds having at least one or more tertiary nitrogen atoms in the molecule, epoxy compounds having no nitrogen compound in the molecule, and the like. As an epoxy compound having at least one or more tertiary nitrogen atoms in the molecule, specifically, epoxy compounds having structures represented by the following formulas (Ep-1) to (Ep-11), or epoxy compounds containing the following Epoxy compounds, etc., in which aliphatic diamines are nitrogen atoms of the parent nucleus. Among them, from the viewpoint of reactivity or availability, epoxy compounds having structures represented by (Ep-4) to (Ep-9) or compounds containing a nitrogen atom with an aliphatic diamine as the parent nucleus are preferred. Synthesized epoxy compounds, etc.

X represents a single bond or an aliphatic or aromatic group with 1 to 6 carbons, and Y represents methylene, ethylidene, trimethylene, ethylene, isopropylidene, vinylidene, Any of vinylidene, oxy, imino, thio, and sulfonyl groups, R ₁ to R ₃ represent a hydrogen atom or an aliphatic group with 1 to 6 carbons, and j represents 0 to 4 an integer of . Among the epoxy compounds with at least one tertiary nitrogen atom in the molecule, the compound formed by bonding the tertiary nitrogen atom with at least one aliphatic group or alicyclic group can be shortened It is suitable for firing time.

Specific examples of epoxy compounds having at least one tertiary nitrogen atom in the molecule include N,N-diglycidylaniline, N,N-diglycidyltoluidine, N,N-di Glycidylcyclohexylamine, N,N-diglycidylmethylcyclohexylamine, N,N,N',N'-tetraglycidyl-p-phenylenediamine, N,N,N',N '-tetraglycidyl-m-phenylenediamine, N,N,N',N'-tetraglycidyl-o-phenylenediamine, N,N,N',N'-tetraglycidyl-4 ,4'-Diaminodiphenylmethane, N,N,N',N'-tetraglycidyl-3,4'-diaminodiphenylmethane, N,N,N',N'- Tetraglycidyl-3,3'-diaminodiphenylmethane, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylsulfide, N,N ,N',N'-tetraglycidyl-1,5-diaminonaphthalene, N,N,N',N'-tetraglycidyl-2,7-diaminoterpene, N,N,N ',N'-tetraglycidyl-4,4'-diaminodiphenyl ether, N,N,N',N'-tetraglycidyl-2,2-bis[4-(4-amine ylphenoxy)phenyl]propane, N,N,N',N'-tetraglycidyl-9,9-bis(4-aminophenyl) terpene, N,N,N',N'- Tetraglycidyl-2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, N,N,N',N'-tetraglycidyl-2,2-bis( 4-aminophenyl)hexafluoropropane, N,N,N',N'-tetraglycidyl-4,4'-(p-phenylenediisopropylidene)bisaniline, N,N, N',N'-tetraglycidyl-4,4'-(m-phenylenediisopropylidene)bisaniline, N,N,N',N'-tetraglycidyl-1,4- Bis(4-aminophenoxy)benzene, N,N,N',N'-tetraglycidyl-4,4'-bis(4-aminophenoxy)biphenyl, N,N,N ',N'-Tetraglycidyl-m-stubble diamine, N,N,N',N'-tetraglycidyl-p-stuft diamine, 1,3-bis(N,N '-Diglycidylaminomethyl)cyclohexane, 1,4-bis(N,N'-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetra Glycidyl-1,4-cyclohexanediamine, N,N,N',N'-tetraglycidyl-1,3-cyclohexanediamine, N,N,N',N'-tetraglycidyl-1,3-cyclohexanediamine Glycidyl-4,4'-methylenebis(cyclohexylamine), N,N,N',N'-tetraglycidyl-diaminoethane, N,N,N',N'- Tetraglycidyl-diaminopropane, N,N,N',N'-tetraglycidyl-diaminobutane, N,N,N',N'-tetraglycidyl-diaminopentane Alkane, N,N,N',N'-tetraglycidyl-diaminohexane, N,N,N',N'-tetraglycidyl-diaminoheptane, N,N,N' , N'-tetraglycidyl-diaminooctane, etc.

Specific examples of epoxy compounds that do not have a nitrogen compound in the molecule include trade names "Epikote 828", "Epikote 834", "Epikote 1001", "Epikote 1004" manufactured by Mitsubishi Chemical Corporation, Dainippon Ink Chemicals, etc. Bisphenol A type epoxy compounds such as "Epiclon 840", "Epiclon 850", "Epiclon 1050", "Epiclon 2055" manufactured by Kogyo Co., Ltd., and "Epotohto 128" manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.; Trade name "Epiclon 830S" manufactured by Dainippon Ink Chemical Industry Co., Ltd., trade name "Epikote 807" manufactured by Mitsubishi Chemical Corporation, trade name "Epotohto YDF-170" and "Epotohto YDF-175" manufactured by Nippon Steel Sumikin Chemical Co., Ltd., Bisphenol F-type epoxy compounds such as "Epotohto YDF-2004"; Nippon Kayaku's trade name "EBPS-200", Asahi Denka Kogyo's trade name "EPX-30", Dainippon Ink Chemicals Co., Ltd. Bisphenol S-type epoxy compounds such as the trade name "Epiclon EXA1514" produced by Osaka Gas Co., Ltd., such as the trade name "BPFG" and other bisphenol S-type epoxy compounds, the trade name "YL-6056" produced by Mitsubishi Chemical Corporation, Bixylenol-type or biphenyl-type epoxy compounds such as "YL-6021", "YX-4000", "YX-4000H", or mixtures thereof; trade names manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. " Hydrogenated bisphenol A type epoxy compounds such as "Epotohto ST-2004", "ST-2007", and "ST-3000"; Mitsubishi Chemical Corporation's trade name "Epikote 152", "Epikote 154", Dow Chemical Co., Ltd. Trade names "D‧E‧N‧431", "D‧E‧N‧438", trade names "Epiclon N-690", "Epiclon N-695", "Epiclon N- 730", "Epiclon N-770", "Epiclon N-865", "Epotohto YDCN-701", "Epotohto YDCN-704" manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., "Epotohto YDCN-704" manufactured by Nippon Kayaku Co., Ltd. EPPN-201”, “EOCN-1025”, “EOCN-1020”, “EOCN-104S”, “RE-306” and other novolak-type epoxy compounds; Mitsubishi Chemical Corporation’s trade name “Epikote YL-903” , Brominated bisphenols such as "Epiclon 152" and "Epiclon 165" manufactured by Dainippon Ink Chemical Industry Co., Ltd., and "Epotohto YDB-400" and "Epotohto YDB-500" manufactured by Nippon Steel and Sumikin Chemical Co., Ltd. A-type epoxy compound; Nippon Steel Chemical Co., Ltd. product names "ESN-190", "ESN-360", Dainippon Ink Chemical Industry Co., Ltd. product names "HP-4032", "EXA-4700", " Epoxy compounds having a naphthalene skeleton such as "EXA-4750"; Epoxy compounds having a dicyclopentadiene skeleton such as "HP-7200" and "HP-7200H" manufactured by Dainippon Ink Chemical Industry Co., Ltd.; Mitsubishi Chemical The product name "YL-933" manufactured by the company, the product name "EPPN-501" and "EPPN-502" manufactured by Nippon Kayaku Co., Ltd., and other parahydroxyphenylmethane-type epoxy compounds; the product name " Alicyclic epoxy compounds such as "CELOXIDE 2011", "Araldite CY175" and "Araldite CY179" manufactured by Asahi Kasei Kogyo Co., Ltd., and "HBE-100" manufactured by Shin Nippon Chemical Co., Ltd. are not limited thereto. These epoxy compounds can be used individually or in combination of 2 or more types.

As the compound having two or more epithiol groups at the molecular terminal, it can be obtained, for example, by converting an epoxy group in the above-mentioned epoxy compound having an epoxy group into an epithiol group. As the method of converting the above-mentioned thioethylene group, preferably as follows: the solution containing the above-mentioned epoxy compound having an epoxy group is continuously or intermittently added to the first solution containing a vulcanizing agent, and then further continuously or intermittently A method of intermittently adding a second solution containing a vulcanizing agent. By this method, the above-mentioned epoxy group can be converted into an epithiol group. Examples of the vulcanizing agent include thiocyanates, thioureas, phosphine sulfides, dimethylthioformamide, and N-methylbenzothiazole-2-thione. As said thiocyanate, sodium thiocyanate, potassium thiocyanate, sodium thiocyanate etc. are mentioned. By using the above-mentioned compound having two or more epithiol groups, the cross-linking reaction can be further promoted, so it is suitable in terms of shortening the firing time of the liquid crystal alignment agent.

As the compound having two or more hydroxyalkylamide groups at the molecular terminal, as long as the compound has a hydroxyalkylamide group, other structures are not particularly limited. From the viewpoint of availability, etc. , a compound represented by the following formula (2) is a preferred example.

In the formula, X ₂ is an aliphatic hydrocarbon group with 1 to 20 carbons or an n-valent organic group containing an aromatic hydrocarbon group, n is an integer of 2 to 6, R ₂ and R ₃ are independently hydrogen atoms, or can have The substituent is an alkyl group with 1 to 4 carbons, an alkenyl group with 2 to 4 carbons, or an alkynyl group with ₂ to 4 carbons, and at least one of R2 and _R3 represents a hydrocarbon group substituted by a hydroxyl group. Among them, among X ₂ in the formula (2), the atom directly bonded to the carbonyl group is preferably a carbon atom that does not form an aromatic ring from the viewpoint of liquid crystal alignment. Also, X ₂ in the formula (2) is preferably an aliphatic hydrocarbon group, and preferably has 1 to 10 carbon atoms, from the viewpoint of liquid crystal alignment and solubility, similarly to the above. In formula (2), n represents an integer of 2-6, but n is preferably 2-4 from the viewpoint of solubility. In formula (2), R2 _{and R3} are independently a hydrogen atom, or an alkyl group with 1 to 4 carbons that may have a substituent, an alkenyl group with 2 to 4 carbons, or an alkyne with 2 to 4 carbons A group, at least one of R ₂ and R ₃ represents a hydrocarbon group substituted by a hydroxyl group. Among them, from the viewpoint of reactivity, at least one of R ₂ and R ₃ is preferably a structure represented by the following formula (3a), more preferably a structure represented by the following formula (4a).

In the formula (3a), R ₄ to R ₇ each independently represent any one of a hydrogen atom, a hydrocarbon group, or a hydrocarbon group substituted by a hydroxyl group.

Specific examples of the compound having two or more hydroxyalkylamide groups at molecular terminals include the following compounds.

When there are too many compounds having a hydroxyalkylamide group, unreacted components may dissolve into liquid crystals, which may lower reliability. Therefore, the addition amount of the compound which has a hydroxyalkylamide group is preferably 0.1-40 mass % with respect to the polymer of (A) component, More preferably, it is 1-30 mass %.

Examples of the compound having two or more benzyl alcohol groups at molecular terminals include a compound having a benzyl alcohol group bonded to an aromatic ring with a methyl group interposed between hydroxyl groups. Among these, at least one compound selected from the group consisting of compounds represented by the following formula [1] and compounds represented by formula [2] is preferred.

In the formula, Y ₁ , Y ₂ , and Y ₃ each independently represent an aromatic ring. Any hydrogen atom of the aromatic ring may be substituted with a hydroxyl group, an alkyl group having 1 to 3 carbon atoms, a halogen atom, an alkoxy group having 1 to 3 carbon atoms, or a vinyl group. Z ₁ is a single bond, a divalent saturated hydrocarbon group with 1 to 10 carbon atoms that can be bonded in whole or in part to form a ring structure, and any hydrogen atom can be replaced by a fluorine atom, -NH-, -N(CH ₃ )-, the base represented by formula [3]. t ₁ is an integer of 2 to 4, t ₂ and t ₃ are respectively independently an integer of 1 to 3, and a and b are respectively independently an integer of 1 to 3.

In the formula [3], P ₁ and P ₂ are each independently an alkyl group having 1 to 5 carbon atoms, and Q ₁ represents an aromatic ring.

環、三嗪環、吡唑啶環、三唑環、吡嗪環、苯并咪唑環、苯并咪唑環、噌啉環、啡啉環、吲哚環、喹喔啉環、苯并噻唑環、吩噻嗪環、吖啶環、噁唑環等。作為又較佳的芳香環的具體例，可舉例苯環、萘環、茀環、蒽環、吡咯環、咪唑環、吡唑環、吡啶環、嘧啶環、喹啉環、異喹啉環、咔唑環、嗒

環、吡嗪環、苯并咪唑環、苯并咪唑環、吲哚環、喹喔啉環、吖啶環等。更佳為苯環、萘環、吡啶環、咔唑環，最佳為苯環、吡啶環。Specific examples of this include a benzene ring, a naphthalene ring, a tetrahydronaphthalene ring, an azulene ring, an indene ring, an oxene ring, an anthracene ring, a phenanthrene ring, a phenanthrene ring, a pyrrole ring, an imidazole ring, an oxazole ring, a thiazole ring, a pyrene ring, and a pyrene ring. Azole ring, pyridine ring, pyrimidine ring, quinoline ring, pyrazoline ring, isoquinoline ring, carbazole ring, purine ring, thiadiazole ring, pyridoxine ring

ring, triazine ring, pyrazolidine ring, triazole ring, pyrazine ring, benzimidazole ring, benzimidazole ring, cinnoline ring, phenanthroline ring, indole ring, quinoxaline ring, benzothiazole ring , phenothiazine ring, acridine ring, oxazole ring, etc. Specific examples of further preferable aromatic rings include benzene ring, naphthalene ring, fennel ring, anthracene ring, pyrrole ring, imidazole ring, pyrazole ring, pyridine ring, pyrimidine ring, quinoline ring, isoquinoline ring, Carbazole ring, click

ring, pyrazine ring, benzimidazole ring, benzimidazole ring, indole ring, quinoxaline ring, acridine ring, etc. More preferably, they are benzene rings, naphthalene rings, pyridine rings, and carbazole rings, most preferably, they are benzene rings and pyridine rings.

Furthermore, the hydrogen atoms of these aromatic rings may be substituted by hydroxyl, alkyl groups with 1 to 3 carbon atoms, halogen atoms, alkoxy groups with 1 to 3 carbon atoms, or vinyl groups. t ₂ and t ₃ in formula [2] are preferably an integer of 1 or 2. Also, a and b are preferably 1 or 2. If Z in the formula [2] is a divalent saturated hydrocarbon group with ₁ to 10 carbon atoms (preferably 1 to 5) that can be bonded in whole or in part to form a ring structure, any Hydrogen atoms may be replaced by fluorine atoms.

Examples of _Z1 include an alkylene group having 1 to 10 carbon atoms, an alicyclic hydrocarbon group having 3 to 10 carbon atoms, and a combination of an alkylene group and an alicyclic hydrocarbon group having 1 to 10 carbon atoms. In addition, a group in which arbitrary hydrogen atoms of the aforementioned groups are substituted with fluorine atoms can be exemplified.

環、三嗪環、吡唑啶環、三唑環、吡嗪環、苯并咪唑環、苯并咪唑環、噌啉環、啡啉環、吲哚環、喹喔啉環、苯并噻唑環、吩噻嗪環、吖啶環、噁唑環等。作為又較佳的芳香環的具體例，可舉例苯環、萘環、茀環、蒽環、吡咯環、咪唑環、吡唑環、吡啶環、嘧啶環、喹啉環、異喹啉環、咔唑環、嗒

環、吡嗪環、苯并咪唑環、苯并咪唑環、吲哚環、喹喔啉環、吖啶環等。更佳為苯環、萘環、吡啶環、咔唑環、茀環等。Q in the formula [3] is an aromatic ring, and as this specific example, a benzene ring, a naphthalene ring _, a tetrahydronaphthalene ring, an azulene ring, an indene ring, an azulene ring, an anthracene ring, a phenanthrene ring, a naphthalene ring, a pyrrole ring, Imidazole ring, oxazole ring, thiazole ring, pyrazole ring, pyridine ring, pyrimidine ring, quinoline ring, pyrazoline ring, isoquinoline ring, carbazole ring, purine ring, thiadiazole ring, pyrene

ring, triazine ring, pyrazolidine ring, triazole ring, pyrazine ring, benzimidazole ring, benzimidazole ring, cinnoline ring, phenanthroline ring, indole ring, quinoxaline ring, benzothiazole ring , phenothiazine ring, acridine ring, oxazole ring, etc. Specific examples of further preferable aromatic rings include benzene ring, naphthalene ring, fennel ring, anthracene ring, pyrrole ring, imidazole ring, pyrazole ring, pyridine ring, pyrimidine ring, quinoline ring, isoquinoline ring, Carbazole ring, click

ring, pyrazine ring, benzimidazole ring, benzimidazole ring, indole ring, quinoxaline ring, acridine ring, etc. More preferably, they are a benzene ring, a naphthalene ring, a pyridine ring, a carbazole ring, a fennel ring, and the like.

Examples of the compound having two or more benzyl alcohol groups at molecular terminals include compounds of [P1] to [P45], but are not limited thereto. As the compound having two or more benzyl alcohol groups at the molecular terminal, compounds represented by [P13], [P15], [P18], [P20], [P26] are preferable, and among them, [ Compounds represented by P13], [P18], and [P20].

(B) The amount of component used is preferably 0.1 to 40 parts by mass, and more preferably 0.5 parts by mass relative to 100 parts by mass of the first specific polymer and/or the second specific polymer contained in the liquid crystal alignment agent. Parts by mass~20 parts by mass. In addition, the (B) component can be used alone as one type of compound, and can also be used in combination of two or more types of compounds.

<Solvent> The solvent used in the liquid crystal alignment agent of the present invention is not particularly limited as long as it can dissolve the first specific polymer and the second specific polymer. Specific examples include N-alkyl-2-pyrrolidones such as water, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N,N-dimethyl Formamide, N,N-dimethylacetamide, N-methylcaprolactam, tetramethylurea, 3-methoxy-N,N-dimethylacrylamide, 3-ethoxy Dialkyl imidazolines such as -N,N-dimethylpropionamide, 3-butoxy-N,N-dimethylpropionamide, 1,3-dimethyl-2-imidazolidinone, etc. Ketones, lactones such as γ-butyrolactone, γ-valerolactone, and δ-valerolactone, carbonates such as ethyl carbonate and propylene carbonate, methanol, ethanol, propanol, isopropyl Alcohol, 3-methyl-3-methoxybutanol, ethyl amyl ketone, methyl nonyl ketone, methyl ethyl ketone, isoamyl methyl ketone, methyl isopropyl ketone, diisobutyl Ketones such as ketone, cyclohexanone, methyl isobutyl ketone, 4-hydroxy-4-methyl-2-pentanone, compounds represented by the following formula (Sv-1) and the following formula (Sv -2) The compound represented, 4-methyl-2-pentyl acetate, 2-ethylbutyl acetate, 2-ethylhexyl acetate, cyclohexyl acetate, 2-methylcyclohexyl acetate, butyl butyl butyrate, isopentyl butyrate, diisobutyl carbinol, diisoamyl ether, etc.

In the formulas (Sv-1)~(Sv-2), Y ₁ and Y ₂ are independently a hydrogen atom or a monovalent hydrocarbon group with 1 to 6 carbons, X ₁ is an oxygen atom or -COO-, and X ₂ is a Single bond or carbonyl, _R1 is an alkanediyl group with 2 to 4 carbons. n ₁ is an integer from 1 to 3. When n ₁ is 2 or 3, the plurality of R ₁ may be the same or different. For example, Z ₁ is a divalent hydrocarbon group having 1 to 6 carbons, Y ₃ and Y ₄ are each independently a hydrogen atom or a monovalent hydrocarbon group having 1 to 6 carbons), and the like.

In the formula (Sv-1), as the monovalent hydrocarbon group having 1 to 6 carbon atoms of _Y1 and _Y2 , for example, a monovalent chain hydrocarbon group having 1 to 6 carbon atoms, a monovalent hydrocarbon group having 1 to 6 carbon atoms, Alicyclic hydrocarbon groups and monovalent aromatic hydrocarbon groups with 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 of R ₁ may be linear or branched.

In formula (Sv-2), as the divalent hydrocarbon group having 1 to 6 carbon atoms of _Z1 , for example, an alkanediyl group having 1 to 6 carbon atoms may be mentioned. Examples of the monovalent hydrocarbon groups having 1 to 6 carbon atoms of _Y3 and _Y4 include monovalent chain hydrocarbon groups having 1 to 6 carbon atoms, monovalent alicyclic hydrocarbon groups having 1 to 6 carbon atoms, and monovalent hydrocarbon groups having 1 to 6 carbon atoms. ~6 monovalent aromatic hydrocarbon groups, etc. 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 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 Alcohol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether Diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether, dipropylene glycol dimethyl ether Ether, dipropylene glycol monomethyl ether, propylene glycol diacetate, ethylene glycol, 1,4-butanediol, 3-methoxybutyl acetate, 3-ethoxybutyl acetate, etc.; Specific examples of the solvent represented by (Sv-2) include methyl glycolate, ethyl glycolate, butyl glycolate, ethyl lactate, butyl lactate, isopentyl lactate, ethyl-3- Ethoxypropionate, methyl-3-methoxypropionate, ethyl 3-methoxypropionate, 3-ethoxypropionate, 3-methoxypropionate, 3-methoxy Propyl propionate, 3-methoxybutyl propionate, etc.

As the aforementioned solvent, it is preferable to have a boiling point of 80 to 200°C. It is also preferably 80°C~180°C. As a preferable solvent, N,N-dimethylformamide, tetramethylurea, 3-methoxy-N,N-dimethylacrylamide Amine, propanol, isopropanol, 3-methyl-3-methoxybutanol, ethyl amyl ketone, methyl ethyl ketone, isoamyl methyl ketone, methyl isopropyl ketone, diiso Butyl ketone, cyclohexanone, methyl isobutyl ketone, 4-hydroxy-4-methyl-2-pentanone, 4-methyl-2-pentyl acetate, 2-ethylbutyl acetate, acetic acid cyclo Hexyl ester, 2-methylcyclohexyl acetate, butyl butyrate, isopentyl butyrate, diisobutylmethanol, diisoamyl 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, Ethyl Glycolate, Butyl Glycolate, Ethyl Lactate, Lactic Acid Butyl ester, isopentyl lactate, ethyl-3-ethoxypropionate, methyl-3-methoxypropionate, ethyl 3-methoxypropionate, etc. It is preferable to make the boiling point within this range, especially when the liquid crystal alignment agent containing the aforementioned solvent is applied to the plastic substrate described later.

<Production method of specific polymer> The first specific polymer and the second specific polymer contained in the liquid crystal alignment agent of the present invention can be obtained as follows: the above-mentioned (A-1) in the molecule A monomer having at least one functional group selected from a carboxyl group, an amine group, and a hydroxyl group, (b) a monomer having a photoalignment site, and (c) thermally crosslinkable with respect to the first specific polymer The monomers of the base are polymerized. Moreover, it can copolymerize with other monomers other than the above. Examples of other monomers include industrially available monomers capable of radical polymerization.

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

Examples of acrylate compounds include methyl acrylate, ethyl acrylate, isopropyl acrylate, benzyl acrylate, naphthyl acrylate, anthracene acrylate, anthracenylmethyl acrylate, phenyl acrylate, acrylic acid 2,2,2 - Trifluoroethyl, tert-butyl acrylate, cyclohexyl acrylate, isocamyl 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-acrylate Tricyclodecanyl, and, 8-ethyl-8-tricyclodecanyl acrylate, etc.

Examples of the methacrylate compound include alkanes such as methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, hexadecyl methacrylate, and octadecyl methacrylate. methacrylate, benzyl methacrylate, naphthyl methacrylate, anthracenyl methacrylate, anthracenylmethyl methacrylate, phenyl methacrylate, 2,2,2-trimethacrylate Fluoroethyl, tert-butyl methacrylate, cyclohexyl methacrylate, isocamyl methacrylate, 2-methoxyethyl methacrylate, methoxytriethylene glycol methacrylate, 2-Ethoxyethyl methacrylate, tetrahydrofurfuryl methacrylate, 3-methoxybutyl methacrylate, 2-methyl-2-adamantyl methacrylate, 2-methacrylate Propyl-2-adamantyl ester, 8-methyl-8-tricyclodecanyl methacrylate, and 8-ethyl-8-tricyclodecanyl methacrylate, etc.

Examples of the vinyl compound include vinyl ether, methyl vinyl ether, benzyl vinyl ether, 2-hydroxyethyl vinyl ether, phenyl vinyl ether, and propyl vinyl ether. As a styrene compound, styrene, methylstyrene, chlorostyrene, bromostyrene, etc. are mentioned, for example. The nitrogen-containing aromatic heterocyclic ring system must contain at least 1 (preferably 1 to 4) selected from the following formula [Na] ~ [Nb] (wherein, Z ₂ is a straight chain with 1 to 5 carbons) Or branched chain alkyl) aromatic ring hydrocarbon group structure is preferred.

環、三嗪環、吡嗪環、啡啉環、喹喔啉環、苯并噻唑環、噁二唑環、吖啶環等。進一步，於該等的含氮芳香族雜環的碳原子中，可具有包含雜原子的取代基。該等之中，可舉例如吡啶環。Specifically, oxazole ring, thiazole ring, pyridine ring, pyrimidine ring, quinoline ring, 1-pyrazoline ring, isoquinoline ring, thiadiazole ring, pyridine ring,

ring, triazine ring, pyrazine ring, phenanthroline ring, quinoxaline ring, benzothiazole ring, oxadiazole ring, acridine ring, etc. Furthermore, the carbon atoms of these nitrogen-containing aromatic heterocycles may have a substituent containing a heteroatom. Among these, a pyridine ring is mentioned, for example.

Examples of monomers containing nitrogen-containing aromatic heterocyclic groups and polymerizable groups include 2-(2-pyridylcarbonyloxy)ethyl (meth)acrylate, 2-(3-pyridine (meth)acrylate) 2-(4-pyridylcarbonyloxy)ethyl (meth)acrylate, etc.

As the acrylamide compound, in addition to the above-mentioned N-methoxymethyl(meth)acrylamide, N-butoxymethyl(meth)acrylamide, and acrylamide, methacrylamide can be exemplified. Amide, N-methacrylamide, N,N-dimethylacrylamide, N,N-diethylacrylamide, N-methylmethacrylamide, N,N-dimethylacrylamide Methacrylamide, N,N-diethylmethacrylamide, etc.

The other monomers used in the present invention may be used alone or in combination of two or more monomers. The content of the above-mentioned other monomers is 0~60mol%, 0~40mol%, or 1~40mol%, or 5~40mol%, 60~99mol%, or 60-95 mol%, 60-99 mol%, or 60-95 mol%, 0-20 mol%, or 1-20 mol%, or 5-20 mol% are preferably other monomers contained above. In this case, the total of the aforementioned sites having polar groups, photoreactive sites, and thermally crosslinkable sites in the molecule is preferably 40 to 100 mol%, 60 mol% of the first specific polymer (A) component. ~100mol%, 80~100mol%, or 80~99mol%, or 80~95mol%. Alternatively, the content of other monomers is 0 to 60 mol%, 0 to 40 mol%, or 1 to 40 mol%, or 5 to 40 mol% of the second specific polymer (component (A)) to include the other Monomer is preferred. In this case, the total of the sites having polar groups in the molecule and the photoreactive sites is preferably 40 to 100 mol%, 60 to 100 mol%, or 60% of the second specific polymer (component (A)). ~99mol%, or 60~95mol%.

The manufacturing method of the 1st specific polymer and the 2nd specific polymer in this invention is not specifically limited, The general method used industrially can be utilized. Specifically, it can be produced by cationic polymerization, radical polymerization, or anionic polymerization using vinyl groups of monomers. Among them, radical polymerization is particularly preferred from the viewpoint of easiness of reaction control and the like. As the polymerization initiator for radical polymerization, known compounds such as radical polymerization initiators and reversible addition-dissociation type chain transfer (RAFT) polymerization reagents can be used.

The radical thermal polymerization initiator is a compound that generates free radicals by heating above the decomposition temperature. Such radical thermal polymerization initiators include, for example, ketone peroxides (methyl ethyl ketone peroxide, cyclohexanone peroxide, etc.), diacyl peroxides (acetyl peroxide, benzoyl peroxide, etc.), hydrogen peroxides (hydrogen peroxide, tert-butyl hydroperoxide, cumene hydroperoxide, etc.), dialkyl peroxides (di-tert-butyl peroxide , dicumene peroxide, dilauroyl peroxide, etc.), peroxyketals (dibutylperoxycyclohexane, etc.), alkyl peroxyesters (peroxyneodecanoic acid-tert- Butyl peroxide, pivalate-tert-butyl peroxide, 2-ethylcyclohexane peroxide-tert-pentyl peroxide, etc.), persulfates (potassium persulfate, sodium persulfate, ammonium persulfate, etc.) , Azo compounds (azobisisobutyronitrile, and 2,2'-bis(2-hydroxyethyl) azobisisobutyronitrile, etc.). 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 can initiate radical polymerization by light irradiation. Examples of such radical photopolymerization initiators include benzophenone, Michelerone, 4,4'-bis(diethylamino)benzophenone, xanthone, thioxanthone, and Known compounds such as ketone and isopropylxanthone. These compounds may be used alone or in combination of two or more. The radical polymerization method is not particularly limited, and emulsion polymerization method, suspension polymerization method, dispersion polymerization method, precipitation polymerization method, block polymerization method, solution polymerization method, etc. can be used.

The solvent used for the polymerization reaction of the first specific polymer and the second specific polymer is not particularly limited as long as the produced polymer is soluble. As specific examples, the above-mentioned solvent system can include, for example, N-alkyl-2-pyrrolidones, dialkylimidazolidinones, lactones, carbonates, ketones, and the solvents represented by the above formula (Sv-1). The compound represented and the compound represented by the above-mentioned formula (Sv-2), tetrahydrofuran, 1,4-dioxane, dimethylsulfone, dimethylsulfoxide, hexamethylsulfone, etc. These solvents can be used alone or in combination. Furthermore, even if the produced polymer is a solvent in which the produced polymer is insoluble, it can be mixed with the above-mentioned solvent and used as long as the produced polymer is not precipitated. Also, in free radical polymerization, the oxygen in the solvent will hinder the polymerization reaction, so it is better to use organic solvents that have been degassed as much as possible.

The polymerization temperature at the time of radical polymerization can select arbitrary temperature of 30-150 degreeC, Preferably it is the range of 50-100 degreeC. Also, the reaction can be performed at any concentration, and the monomer concentration is preferably 1 to 50% by mass, and more preferably 5 to 30% by mass. The reaction is carried out at a high concentration in the initial stage, and an organic solvent may be added thereafter. In the above-mentioned radical polymerization reaction, if the ratio of the radical polymerization initiator is large relative to the monomer, the molecular weight of the obtained polymer will become small, and if the ratio of the radical polymerization initiator is small, the obtained The molecular weight of the polymer will become larger, so the ratio of the free radical initiator is preferably 0.1~10mol% relative to the monomer to be polymerized. In addition, various monomer components, solvents, initiators, etc. may be added during polymerization.

[Recovery of Polymers] To recover the produced polymers from the reaction solution obtained by the above reaction, it is sufficient to pour the reaction solution into a poor solvent to precipitate the polymers. Methanol, acetone, hexane, heptane, butyl cellosolve, heptane, ethanol, toluene, benzene, diethyl ether, methyl ethyl ether, water etc. are mentioned as a poor solvent used at the time of precipitation. The polymer obtained by pouring into a poor solvent and precipitating it can be recovered by filtration, and then dried under normal pressure or reduced pressure, at normal temperature or by heating. In addition, the polymer that has been recovered by precipitation can be dissolved in an organic solvent again, and the operation of re-precipitation and recovery can be carried out. Repeating this operation for 2 to 10 times can reduce the impurities in the polymer. As a poor solvent at this time, alcohols, ketones, hydrocarbon groups, etc. are mentioned, for example, Since the efficiency of purification can be further improved by using three or more types of poor solvents selected from these, it is preferable.

The molecular weight of the polymer of the present invention is preferably the weight average molecular weight measured by the GPC (Gel Permeation Chromatography) method when considering the strength of the obtained coating film, the workability of the coating film formation, and the uniformity of the coating film. 2,000 to 1,000,000, preferably 5,000 to 100,000.

[Preparation of liquid crystal alignment agent] The liquid crystal alignment agent (ie, polymer composition) used in the present invention is preferably prepared as a coating solution suitable for forming a liquid crystal alignment film. That is, the liquid crystal alignment agent of the present invention is preferably prepared in a solution, and the solution is formed by dissolving the resin component for forming the resin film in an organic solvent. Here, the said resin component is the 1st specific polymer and 2nd specific polymer ((A) component) already demonstrated. At this time, the content of the first specific polymer is preferably 0.5 to 20% by mass, more preferably 1 to 20% by mass, more preferably 1 to 15% by mass, particularly preferably 1 to 10% by mass is suitable. Alternatively, the content of the second specific polymer is preferably 0.5-20% by mass, more preferably 1-20% by mass, particularly preferably 1-10% by mass, relative to the entire liquid crystal alignment agent.

In the polymer composition of the present embodiment, the above-mentioned resin component may be a polymer that has all of the above-mentioned sites having polar groups, sites having photo-alignment properties, and in the case of the first specific polymer. heat-crosslinkable groups, other polymers (hereinafter also referred to as "other polymers") other than these may be mixed. In this case, as content of other polymers in a resin component, 5-95 mass parts, or 10-90 mass parts are mentioned with respect to 100 mass parts of totals of (A) component and other polymers. Such other polymers can be, for example, made of poly(meth)acrylate or polyamic acid, polyamic acid ester or polyimide, etc., and when the present invention uses the first specific polymer When the first specific polymer does not have the (A-1)~(A-3) position, when the second specific polymer is used in the present invention, it does not have the ( A-1) to (A-2), or, in the case of the first specific polymer, only one or two selected from (A-1) to (A-3), In the case of the second specific polymer, it is a polymer having only any one of (A-1) to (A-2).

<Other components> The liquid crystal alignment agent of the present invention may contain other components than the above-mentioned characteristic polymer components. Such other components include, for example, the component (B) used in the second aspect, that is, containing two or more components selected from the group consisting of epoxy group, epithiol group, and hydroxyalkylamide in the molecule. group, and at least one group of benzyl alcohol groups; and other crosslinking compounds (hereinafter collectively referred to as "crosslinking agent components"), or when coating liquid crystal alignment agents Compounds for improving film thickness uniformity or surface smoothness, compounds for improving adhesion between a liquid crystal alignment film and a substrate, etc., but are not limited thereto.

<Crosslinking agent component> 1. A compound containing two or more groups selected from the group consisting of epoxy group, thioethyl group, hydroxyalkylamide group, and benzyl alcohol group in the molecule It is the above-mentioned (B) component. In the first aspect, the (B) component used in the second aspect may also be contained.

2. Other cross-linking compounds As other cross-linking compounds, in addition to those having an isocyanate group, an oxetanyl group, or a cyclic carbonic acid compound described in paragraphs [0109] to [0113] of International Publication WO2016/047771, In addition to the ester group compound or the compound having at least one group selected from the group consisting of hydroxyl group, hydroxyalkyl group and lower alkoxyalkyl group, compounds having blocked isocyanate group, etc. are exemplified.

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

The usage-amount of (B) component or these crosslinking agent components is 0.1-40 mass parts with respect to 100 mass parts of resin components contained in a polymer composition, Preferably it is 0.1-30 mass parts, and Preferably, 1 to 20 parts by mass is appropriate.

[Compounds that improve film thickness uniformity or surface smoothness] Examples of compounds that improve film thickness uniformity or surface smoothness include fluorine-based surfactants, polysiloxane-based surfactants, and nonionic surfactants. wait. Specifically, examples include F-Top (registered trademark) 301, EF303, EF352 (manufactured by Tokem Products), MegaFace (registered trademark) F171, F173, R-30 (manufactured by DIC Corporation), Florade FC430, FC431 (manufactured by Sumitomo 3M Corporation), AashiGuard (registered trademark) AG710 (manufactured by Asahi Glass Co., Ltd.), Surfuron (registered trademark) S-382, SC101, SC102, SC103, SC104, SC105, SC106 (manufactured by AGC Seimi Chemical Co., Ltd.) and the like. The usage ratio of these surfactants is preferably 0.01 to 2 parts by mass, and more preferably 0.01 to 1 part by mass relative to 100 parts by mass of the resin component contained in the polymer composition.

[Compounds that Improve Adhesion Between Liquid Crystal Alignment Film and Substrate] Specific examples of compounds that improve adhesion between liquid crystal alignment films and substrates include functional silane-containing compounds shown below. Examples include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N -(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxysilane, 3-ureapropyl Trimethoxysilane, 3-ureapropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethyl Oxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4,7 -Triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazenonyl acetate, 9- Triethoxysilyl-3,6-diazenonyl acetate, N-benzyl-3-aminopropyltrimethoxysilane, N-benzyl-3-aminopropyltriethoxy Silane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, N-bis(oxyethylene)-3-aminopropyltrimethoxysilane Aminosilane-containing compounds such as oxysilane and N-bis(oxyethylene)-3-aminopropyltriethoxysilane. When using a compound that enhances adhesion to the substrate, the amount used is preferably 0.1 to 30 parts by mass, more preferably 1 part by mass, relative to 100 parts by mass of the resin component contained in the polymer composition ~20 parts by mass.

In one embodiment, in order to improve the photoreactivity of the photoalignment group, a photosensitizer may also be used as an additive. Specific examples include aromatic 2-hydroxyketone (benzophenone), coumarin, coumarinone, carbonyl dicoumarin, acetophenone, anthraquinone, xanthone, and thioxanthone , and acetophenone ketal, etc.

<Liquid Crystal Alignment Film and Liquid Crystal Display Element> The liquid crystal alignment agent of the present invention can be made into a liquid crystal alignment film by applying it on a substrate and firing it, and then performing an alignment treatment by rubbing treatment or light irradiation, or In some vertical alignment applications, etc., it is non-alignment treatment. As the substrate, glass such as float glass, soda glass, etc.; Poly(alicyclic olefin), polyvinyl chloride, polyvinylidene chloride, polyether ether ketone (PEEK) resin film, poly(PSF), polyether sulfide (PES), polyamide, polyimide, Transparent substrates made of plastics such as acrylic and triacetyl cellulose. As the transparent conductive film provided on one side of the substrate, NESA film (registered trademark of PPG Corporation of the United States) made of tin oxide (SnO ₂ ), or NESA film made of indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ) can be used. into the ITO film, etc.

<Coating film forming step> The coating method of the liquid crystal alignment agent of the present invention is not particularly limited, and examples include screen printing, flexographic printing, offset printing, inkjet, dip coating, roll coating, slot coating, and spin coating. Cloth, etc., can be used according to the purpose. By these methods, after coating on a board|substrate, a solvent is evaporated by heating means, such as a hot plate, and a coating film can be formed.

The firing after coating the liquid crystal alignment agent can be carried out at any temperature from 40°C to 300°C, but preferably from 40°C to 250°C, and more preferably from 40°C to 230°C. When using a transparent substrate made of a plastic substrate, it is preferably set at 40~150°C, and more preferably at 80~140°C. The firing time is preferably 0.1 to 15 minutes, and more preferably 1 to 10 minutes. The film thickness of the coating film formed on the substrate is preferably 5 to 1,000 nm, more preferably 10 to 500 nm or 10 to 300 nm. This firing can be performed with a hot plate, a hot air circulation furnace, an infrared furnace, or the like. Rayon cloth, nylon cloth, cotton cloth, etc. can be used for friction treatment.

<Light irradiation step> In one embodiment, the alignment treatment may also be performed by light irradiation, and may include, for example, the following steps: a step of applying the above-mentioned liquid crystal alignment agent to the substrate to form a coating film; A step of irradiating the aforementioned coating film with light in a state not in contact with the liquid crystal layer or in a state in contact with the liquid crystal layer.

When the alignment treatment is performed by light irradiation, the light to be irradiated includes, for example, ultraviolet rays and visible rays including light having a wavelength of 150 to 800 nm. Among them, ultraviolet rays including light having a wavelength of 300 to 400 nm are preferable. Irradiation light may be polarized or non-polarized. As polarized light, it is preferable to use light including linearly polarized light.

Irradiation of light may be performed from a direction perpendicular to the substrate surface, or from an oblique direction, or a combination thereof, if the light used is polarized light. When irradiating non-polarized light, it is preferable to irradiate from a direction inclined relative to the substrate surface. The amount of light exposure is preferably at least 0.1 mJ/cm ² and less than 1,000 mJ/cm ² , more preferably 1 to 500 mJ/cm ² , more preferably 2 to 200 mJ/cm ² .

The liquid crystal display element of the present invention can be produced by a usual method, and the production method is not particularly limited. The above-mentioned pair of substrates face each other with an appropriate distance between them. In order to make the thickness of the liquid crystal sandwiched between the substrates uniform, a spacer is preferably disposed between the substrates. As the spacer, well-known spacer materials such as a conventional dispersion type spacer and a spacer formed of a composition for forming a photosensitive spacer can be used. Can be used as a spacer.

<Liquid crystal clamping process> When liquid crystal is clamped between board|substrates and a liquid crystal cell is comprised, the following 2 methods can be mentioned, for example. The first method includes arranging a pair of substrates facing each other with a gap (cell pitch) between them so that the liquid crystal alignment films face each other, and bonding the peripheral parts of the pair of substrates together using a sealant. A method of manufacturing a liquid crystal cell by injecting and filling the liquid crystal into the cell spacing defined by the surface of the substrate and an appropriate sealant, and then sealing the injection hole.

As a second method, it is possible to enumerate: coating, for example, a UV-curable sealing material on a designated position on one of the two substrates on which the liquid crystal alignment film has been formed, and further dropping liquid crystal onto the surface of the liquid crystal alignment film. At the specified positions, after that, the other substrate is laminated with the liquid crystal alignment film facing each other, and the liquid crystal is squeezed and diffused to the entire substrate. Next, the substrate is irradiated with ultraviolet light to harden the sealant. This method is used to manufacture liquid crystal cells (ODF (One Drop Fill) method).

As the liquid crystal, depending on the application, a fluorine-based liquid crystal or a cyanide-based liquid crystal having positive or negative dielectric anisotropy, and a liquid crystal compound or a liquid crystal composition polymerized by at least one of heating and light irradiation can be used (hereinafter also referred to as polymerizable liquid crystal or curable liquid crystal composition). In one embodiment, the above-mentioned step of forming the coating film of the liquid crystal alignment agent can be carried out by a roll-to-roll method. If it is carried out by the roll-to-roll method, the manufacturing steps of the liquid crystal display element can be simplified, and the manufacturing cost can be reduced. Then, a polarizing plate is attached to the outer sides of the aforementioned liquid crystal unit cell to obtain a liquid crystal display element.

As the polarizing plate used outside the liquid crystal cell, a polarizing film (referred to as "H film") in which polyvinyl alcohol is stretched and aligned while absorbing iodine is encased in a protective film of cellulose acetate. Polarizing plate, or polarizing plate made of H film itself, etc. As described above, the liquid crystal alignment film obtained from the liquid crystal alignment agent of the present invention has good liquid crystal alignment, excellent pretilt angle performance, and high reliability. Moreover, the liquid crystal display element manufactured by the method of the present invention has excellent display characteristics. [Example]

Monomers represented by "MA-1" and "MA-2", which are monomers having a photo-alignment group (hereinafter referred to as "photo-alignment monomers") used in the examples, were used as monomers having a polar group. Monomers represented by "MAA" or "VBA" for monomers (hereinafter referred to as "polar monomers"), "GMA" as monomers with crosslinkable groups (hereinafter referred to as "crosslinkable monomers") The structures of the monomer represented by ", the compound represented by "TETRAD-C" or "YH-434-L" as the compound (B) component (hereinafter referred to as "crosslinking agent component") are shown below. Furthermore, "MA-2" was synthesized by the synthesis method described in Synthesis Example 1 below. "MAA (methacrylic acid)", "VBA (vinylbenzoic acid)", "MMA", "C18", "TETRAD-C" and "YH-434-L" used commercially available reagents. (photoalignment monomer)

(Polar monomer) MAA: methacrylic acid VBA: 4-vinylbenzoic acid

(Crosslinkable monomer) GMA: Glycidyl methacrylate

(Other monomers) MMA: methyl methacrylate C12: dodecyl methacrylate C18: octadecyl methacrylate MOI-BP: methacrylic acid 2-[(3,5-dimethyl Pyrazolyl)carbonylamino]ethyl ester

(Crosslinking agent component) TETRAD-C: 1,3-bis(N,N'-diglycidylaminomethyl)cyclohexane YH-434-L: N,N,N',N'-tetra Glycidyl-4,4'-diaminodiphenylmethane Primid: β-hydroxyalkylamide represented by the following formula (Primid)

In addition, the abbreviations of the reagents used in this example are as follows. (polymerization initiator) AIBN: azobisisobutyronitrile (solvent) PGME: propylene glycol monomethyl ether CHN: cyclohexanone

<Measurement of ¹ HNMR> Apparatus: Fourier transform type superconducting nuclear magnetic resonance apparatus (FT-NMR) "INOVA-400" (manufactured by Varian) 400 MHz. Solvent: deuterated chloroform (CDCl ₃ ) or deuterated N,N-dimethylsulfene ([D ₆ ]-DMSO). Standard substance: tetramethylsilane (TMS).

<Monomer Synthesis Example 1> Synthesis of [MA-1]:

Add 1-bromo-4-(trans-4-propylcyclohexyl)-benzene (150.0g, 533mmol), tert-butyl acrylate (102.5g, 800mmol), palladium acetate (2.39g, 11 mmol), tris(o-tolyl)phosphine (6.49 g, 21 mmol), tripropylamine (229.3 g, 1600 mmol), and DMAc (750 g), were stirred while heating to 100°C. After completion of the reaction, the reaction solution was filtered to remove insoluble matter, the filtrate was poured into pure water (3.8 L), and neutralized with 12N-HCl aqueous solution. After neutralization, ethyl acetate (2.5 L) was injected to perform extraction. Anhydrous magnesium sulfate was added to the extracted organic layer to dehydrate and dry, and anhydrous magnesium sulfate was filtered. The resulting filtrate was solvent-distilled off with a rotary evaporator, and the crude product was reslurried and washed with cold methanol (180 g), thereby obtaining 144.0 g of [MA-1-1] (white solid) ( Yield 82%).

[MA-1-1] (144.0 g, 441 mmol) and formic acid (1000 g) were put into a 2L four-necked flask, and it stirred, heating to 50 degreeC. After completion of the reaction, the reaction solution was poured into pure water (3.0 L), and the precipitate was filtered. 111.1 g (yield 92%) of [MA-1-2] (white solid) was obtained by reslurry-washing the obtained crude product with ethyl acetate (200g). The results of ¹ H-NMR of the target substance are shown below. From this result, it was confirmed that the obtained solid was the target [MA-1-2]. 1H NMR (400 MHz, [D6]-DMSO):δ12.34 (s,1H), 7.53-7.60 (m,3H), 7.25-7.27 (d,2H), 6.44-6.48 (d,1H), 2.45 -2.51 (t,1H), 1.76-1.83 (t,4H), 1.28-1.48 (m,5H), 1.15-1.21 (m,2H), 0.97-1.07 (m,2H), 0.87-0.89 (t, 3H).

[MA-1-2] (30.0 g, 110 mmol), 2-hydroxyethyl methacrylate (17.2 g, 132 mmol), 1-(3-dimethylaminopropyl) were added to a 2L four-necked flask - 3-ethylcarbodiimide hydrochloride (EDC) (25.7 g, 165 mmol), 4-dimethylaminopyridine (1.35 g, 11 mmol), THF (150 g), and stirred at room temperature. After completion of the reaction, the reaction solution was poured into ethyl acetate (1.0 L), and extracted with pure water (800 ml). Anhydrous magnesium sulfate was added to the extracted organic layer to dehydrate and dry, and anhydrous magnesium sulfate was filtered. The obtained filtrate was subjected to solvent distillation with a rotary evaporator. The resulting residue was isolated by silica gel column chromatography (ethyl acetate: hexane = 1:5 volume ratio) to obtain 26.8 g of [MA-1] (white solid) (yield 55%). The results of ¹ H-NMR of the target substance are shown below. From this result, it was confirmed that the obtained solid was the target [MA-1]. 1H NMR (400 MHz, [D6]-DMSO):δ7.62-7.66 (m,3H), 7.25-7.27 (d,2H), 6.58-6.62 (d,1H), 6.05 (s,1H), 5.70 (s,1H), 4.37-4.42 (m,4H), 2.44-2.48 (t,1H), 1.88 (s,3H), 1.76-1.82 (t,4H), 1.24-1.47 (m,5H), 1.15 -1.21 (m,2H), 0.96-1.06 (m,2H), 0.85-0.89 (t,3H).

<Monomer Synthesis Example 2> Synthesis of [MA-2]:

Add 1-bromo-4-(trans-4-pentylcyclohexyl)-benzene (150.0g, 485mmol), tert-butyl acrylate (93.24g, 728mmol), palladium acetate in a 2L four-necked flask (2.18g, 9.7mmol), tris(o-tolyl)phosphine (5.90g, 20mmol), tripropylamine (208.5g, 1455mmol) and DMAc (750g) were stirred while heating to 100°C. After completion of the reaction, the reaction solution was filtered to remove insoluble matter, the filtrate was poured into pure water (3.8 L), and neutralized with 12N-HCl aqueous solution. After neutralization, ethyl acetate (2.5 L) was injected to perform extraction. Anhydrous magnesium sulfate was added to the extracted organic layer to dehydrate and dry, and anhydrous magnesium sulfate was filtered. The obtained filtrate was solvent-distilled off with a rotary evaporator, and the crude product was reslurried and washed with cold methanol (190 g), thereby obtaining 137.0 g of [MA-2-1] (white solid) ( Yield 79%).

[MA-2-1] (137.0 g, 384 mmol) and formic acid (1000 g) were put into a 2L four-necked flask, and it stirred, heating to 50 degreeC. After the reaction, the reaction solution was poured into pure water (3.0 L), and the precipitate was filtered. [MA-2-2] (white solid) 111.8g was obtained by reslurry-washing the obtained crude product with ethyl acetate (200g) (96% of yield). The results of ¹ H-NMR of the target substance are shown below. From this result, it was confirmed that the obtained solid was the target [MA-2-2]. 1H NMR (400 MHz, [D ₆ ]-DMSO):δ12.34 (s,1H), 7.53-7.60 (m,3H), 7.25-7.27 (d,2H), 6.44-6.48 (d,1H), 2.45-2.51 (t,1H), 1.77-1.83 (t,4H), 1.38-1.48 (m,2H), 1.17-1.34 (m,9H), 0.97-1.07 (m,2H), 0.87-0.89 (t ,3H).

[MA-2-2] (30.0g, 100mmol), 2-hydroxyethyl methacrylate (15.6g, 119mmol), 1-(3-dimethylaminopropyl)- 3-Ethylcarbodiimide hydrochloride (EDC) (28.7 g, 150 mmol), 4-dimethylaminopyridine (1.22 g, 10 mmol), THF (150 g), and stirred at room temperature. After completion of the reaction, the reaction solution was poured into ethyl acetate (1.0 L), and extracted with pure water (800 ml). Anhydrous magnesium sulfate was added to the extracted organic layer to dehydrate and dry, and anhydrous magnesium sulfate was filtered. The obtained filtrate was subjected to solvent distillation with a rotary evaporator. The resulting residue was isolated by silica gel column chromatography (ethyl acetate:hexane=1:5 volume ratio) to obtain 36.6 g of [MA-2] (white solid) (yield 88%). The results of ¹ H-NMR of the target substance are shown below. From this result, it was confirmed that the obtained solid was the target [MA-2]. 1H NMR (400 MHz, [D ₆ ]-DMSO):δ7.62-7.66 (m,3H), 7.25-7.27 (d,2H), 6.58-6.62 (d,1H), 6.04 (s,1H), 5.70 (s,1H), 4.36-4.42 (m,4H), 2.48-2.52 (t,1H), 1.88 (s,3H), 1.76-1.83 (t,4H), 1.36-1.44 (m,2H), 1.18-1.31 (m,9H), 1.00-1.03 (m,2H), 0.85-0.88 (t,3H).

(Determination of molecular weight) The molecular weight of the polymer in the synthesis example uses a normal temperature gel permeation chromatography (GPC) device (SSC-7200, Shodex company column (KD-803, KD-805) manufactured by Senshu Science Co., Ltd., according to Measure in the following manner. Column temperature: 50°C Eluent: DMF (30mmol/L of lithium bromide-hydrate (LiBr・H2O) as an additive, 30mmol/L of phosphoric acid・anhydrous crystal (o-phosphoric acid), THF is 10ml/L) Flow rate: 1.0ml/min Standard sample for measuring line production: TSK standard polyethylene oxide (molecular weight: about 9000,000, 150,000, 100,000, 30,000) manufactured by Tosoh Corporation, and manufactured by Polymer Laboratories Polyethylene glycol (molecular weight about 12,000, 4,000, 1,000).

<Methacrylate Polymer Synthesis Example A1> Dissolve MA-2 (2.48g, 6.01mmol), GMA (0.14g, 1.00mmol) and MAA (1.2g, 13.0mmol) in CHN (11.0g) and PGME (11.0 g), after degassing with a diaphragm pump, AIBN (0.2 g, 1.0 mmol) was added as a polymerization initiator, and degassing was performed again. Then, it was made to react at 60 degreeC for 13 hours, and the polymer solution (MP-1) was obtained. The polymer has a number average molecular weight of 40,500 and a weight average molecular weight of 138,300.

<Methacrylate Polymer Synthesis Examples A2~A10 and A11~A18> Using the composition shown in Table 1, use the same method as Polymer Synthesis Example A1 to synthesize methacrylate polymers PA2~PA10 and PA11~ PA18.

<Example A1> CHN (5.5g), PGME (5.5g) and TETRAD-C (0.03g) were added to 4.0g of the polymer solution (MP-1) obtained in the methacrylate polymer synthesis example A1, And by stirring at room temperature, the liquid crystal alignment treatment agent (PM-A1) was obtained.

<Example A2~A23 and A24~PA40, Comparative Example A1> With the composition shown in Table 2, use the same method as Example A1 to obtain liquid crystal alignment treatment agents (PM-A2)~(PM-A23) and (PM-A24)~(PM-A40). Moreover, the liquid crystal alignment treatment agent (RPM-A1) of the comparative example A1 was also prepared by the same method.

<Production of liquid crystal display elements> Using a membrane filter with a pore size of 1 μm, the liquid crystal alignment treatment agents (PM-A1)~(PM-A40) obtained in the examples and the liquid crystal alignment treatment agents obtained in the comparative examples (RPM-A1 ) for pressure filtration. The obtained 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 50°C for 120 seconds, and then fired on a hot plate at 120°C for 2 minutes or 20 minutes to form a liquid crystal alignment film with a film thickness of 100 nm. Next, irradiate 50mJ/ ^cm2 of 313nm linearly polarized ultraviolet rays with an irradiation intensity of 4.3mW/cm2 at an angle of 40° from the normal direction of the substrate through a polarizing plate on the coating surface to obtain a substrate with a liquid crystal ^alignment film . Make the ultraviolet light of the high-pressure mercury lamp pass through a 313nm band-pass filter, and then pass through a 313nm polarizer to modulate the linearly polarized ultraviolet light. Two of the above-mentioned substrates were prepared, and a sealant (manufactured by Mitsui Chemicals, XN-1500T) was applied after spreading 4 μm bead spacers on the liquid crystal alignment film of one substrate. Next, another substrate was bonded so that the liquid crystal alignment film faces faced each other and the alignment direction was 180°, and then the sealant was thermally cured at 120° C. for 90 minutes to produce an empty unit cell. A liquid crystal (manufactured by Merck, MLC-3022) was injected into this empty cell by a reduced pressure injection method to obtain a liquid crystal display element.

<Evaluation> (Liquid Crystal Orientation) The liquid crystal display element obtained above was subjected to an isotropic phase treatment at 120° C. for 1 hour, and then cell observation was performed with a polarizing microscope. The case where there was no misalignment such as light leakage or domain generation, or the case where uniform liquid crystal drive was obtained when a voltage was applied to the liquid crystal cell was set to be good. The evaluation results are shown in Table 3.

(Pretilt angle) The pretilt angle of the liquid crystal cell was measured with respect to the liquid crystal display element manufactured above, and it measured by the Muller matrix method using AxoScan by Axo Metrix company. The evaluation results are shown in Table 3.

As can be seen from the above results, from the comparison of Examples A1~A2 and Comparative Example A1, due to the copolymerization of cross-linking monomers, liquid crystals with excellent liquid crystal alignment and liquid crystal pretilt angle performance can be obtained. Alignment film. Furthermore, from the comparison between Example A2 and Example A3, due to the addition of the crosslinking agent component, even when the firing conditions are treated for a short time, it is possible to obtain a product with excellent liquid crystal alignment and excellent pretilt angle display performance. Liquid crystal alignment film.

<Methacrylate Polymer Synthesis Example B1> Dissolve MA-2 (2.5g, 6.0mmol) and MAA (1.2g, 14.1mmol) in CHN (11.0g) and PGME (11.0g), and use a diaphragm pump After degassing, AIBN (0.2 g, 1.0 mmol) was added as a polymerization initiator, and degassing was performed again. Then, it was made to react at 60 degreeC for 13 hours, and the polymer (PB1) solution was obtained. The polymer has a number average molecular weight of 40,500 and a weight average molecular weight of 138,300.

<Methacrylate Polymer Synthesis Examples B2~B8 and B12~B18> Using the composition shown in Table 4, use the same method as Polymer Synthesis Example B1 to synthesize methacrylate polymers PB2~PB8 and PB12~ PB18.

<Methacrylate Polymer Synthesis Example B9> Dissolve MA2 (6.19g, 15.0mmol) and MOI-BP (8.80g, 35.0mmol) in CHN (61.6g) and degas with a diaphragm pump, then add AIBN (0.41 g, 2.5 mmol) was degassed again. Then, it was made to react at 55 degreeC for 13 hours, and the polymer solution of the methacrylate was obtained. This polymer solution was dropped into a mixed solvent (1000 ml) of methanol and pure water=5/5, and the obtained precipitate was filtered. The precipitate was washed with methanol, and dried under reduced pressure in a 40° C. oven to obtain a methacrylate polymer powder. The polymer had a number average molecular weight of 43,600 and a weight average molecular weight of 131,200. CHN (9.0 g) and PGME (9.0 g) were added to the obtained methacrylate polymer powder (1.5 g), and stirred at room temperature for 5 hours to dissolve it, thereby obtaining a polymer (PB9) solution.

<Methacrylate polymer synthesis examples B10 to B11> Using the composition shown in Table 5, methacrylate polymers PB10 to PB11 were synthesized by the same method as in polymer synthesis example P1.

<Example B1> CHN (5.5 g), PGME (5.5 g) and TETRAD-C (0.02 g) were added to 4.0 g of the polymer solution (PB1) obtained in the methacrylate polymer synthesis example B1, and The liquid crystal alignment treatment agent (PM-B1) was obtained by stirring at room temperature.

<Examples B2 to B16, Comparative Example B1> Using the composition shown in Table 6, the liquid crystal alignment treatment agents (PM-B2) to (PM-B16) were obtained by the same method as in Example B1. Moreover, the liquid crystal alignment treatment agent (RPM-B1) of the comparative example B1 was also prepared by the same method.

<Examples B17 to B23> Using the composition shown in Table 6, the same method as in Example B1 was used to obtain liquid crystal alignment treatment agents (PM-B17) to (PM-B23).

<Example B24~B34> With the composition shown in Table 7, the same method as Example B1 was used to obtain liquid crystal alignment treatment agents (PM-B24)~(PM-B34).

<Comparative Example B2> Add CHN (9.0g), PGME (9.0g), YH-434-L (0.15g) to the methacrylate polymer solution (PB9), and stir at room temperature for 5 hours to make it Dissolved to obtain a liquid crystal alignment treatment agent (RPMB-2).

<Manufacturing of liquid crystal display elements> Use the liquid crystal alignment treatment agent (PM-B1)~(PM-B34) and the liquid crystal alignment treatment agent (RPM-B1)~(RPM-B2) obtained in the comparative example instead of the example The obtained liquid crystal alignment treatment agents (PM-A1) to (PM-A36) and the liquid crystal alignment treatment agent (RPM-A1) obtained in the comparative example were prepared in the same manner as above to produce a liquid crystal display element. Also, the liquid crystal alignment and pretilt angle were evaluated in the same manner, and the evaluation results are shown in Table 8.

As can be seen from the above results, from the comparison between Example B1 and Comparative Example B1, due to the introduction of the crosslinking agent component, the liquid crystal display element using the liquid crystal alignment film obtained by the liquid crystal alignment treatment agent of the present invention, even if it is short Time firing can also exhibit pretilt angle. Furthermore, from the comparison between Example B1 and Comparative Example B2, the liquid crystal display element using the liquid crystal alignment film obtained by the liquid crystal alignment agent that does not contain polar groups in the molecule cannot obtain liquid crystal alignment. The liquid crystal display element of the liquid crystal alignment film obtained by the liquid crystal alignment treatment agent of the invention has good liquid crystal alignment and also exhibits a pretilt angle. [Industrial Utilization]

The liquid crystal display element using the liquid crystal alignment film obtained from the liquid crystal alignment treatment agent of this invention can be suitably used for a liquid crystal display element.

Claims (20)

A liquid crystal alignment agent, which is a liquid crystal alignment agent containing (A) component: a polymer having the following (A-1) and (A-2) structures; and a solvent liquid crystal alignment agent, and the above polymer further has (A-3) having Groups selected from oxetanyl groups, oxirane groups, groups represented by the following formula (3), groups represented by the following formula (4), groups represented by the following formula (5), and episulfide The structure of at least one functional group of ethyl group; (A-1) the structure of at least one functional group selected from carboxyl, amine and hydroxyl groups in the molecule; (A-2) the following formula (pa -1) (In the formula, A means that it is optionally substituted by a group selected from fluorine, chlorine, and cyano, or by an alkoxy group with 1 to 5 carbons, a linear or branched alkyl residue (this is optionally substituted by 1 cyano group or more than 1 halogen atom) substituted pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-thienyl, 2 , 5-furyl, 1,4- or 2,6-naphthyl or phenylene, R ₁ is a single bond, oxygen atom, -COO- or -OCO-, R ₂ is a divalent aromatic group , 2-valent alicyclic group, 2-valent heterocyclic group or 2-valent condensed ring group, R ₃ is a single bond, oxygen atom, -COO- or -OCO-, R ₄ is a carbon number of 1 to 40 straight-chain or branched-chain alkyl group or a monovalent organic group with 3 to 40 carbon atoms containing an alicyclic group, D represents an oxygen atom, a sulfur atom or -NR _d - (herein, R _d represents hydrogen atom or an alkyl group with 1 to 3 carbons), a is an integer of 0 to 3, * represents the bonding position, X and Y are independently a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group or a carbon number of 1 to 3 3’s alkyl group), if the aforementioned (A) component has a carboxyl group structure in the molecule, the aforementioned polymer is derived from the following formula (a-1-m) (wherein, I _a1 is a carboxyl group , r ¹ is 1 or 2, S _a represents a single bond, or an alkanediyl group with 1 to 10 carbons, an arylylene group with 6 to 20 carbons, (*A)-CONH-R ₆ -(*B) group or (*A)-COO-R ₇ -(*B) group, M _a represents the following formula (M _a -1)~(M _a -2) (R ₁ represents a hydrogen atom or carbon number 1~ 5’s alkyl group, * means the bonding part), α-methylene-γ-butyrolactone, maleimide, norcamphene and the radical polymerizable group of the derivatives thereof, or siloxane, R ₆ and R ₇ are mutually independent representations of a single bond, or an alkanediyl group with 1 to 12 carbons, or an arylylene group with 6 to 20 carbons, and any carbon-carbon bond of the alkanediyl group may have an -O-bond, (*A) represents a bonded part with a carbon atom having an unsaturated bond, (*B) represents a bonded part with _Ia1 ) represents a monomer,

*-CH=CH-* (M _a -2). A liquid crystal alignment agent comprising (A) component: a polymer having the following (A-1) and (A-2) structures; (B) component other than the above-mentioned (A) component; and a liquid crystal alignment agent of a solvent , the (B) component is a compound containing two or more groups selected from epoxy groups, epithioethylene groups, hydroxyalkylamide groups, and benzyl alcohol groups in the molecule; (A-1 ) has a structure in the molecule of at least one functional group selected from carboxyl, amine and hydroxyl groups; (A-2) the following formula (pa-1) (wherein, A means that it is selected from fluorine, Substituted by chlorine or cyano group, or by an alkoxy group with 1 to 5 carbons, a linear or branched alkyl residue (this is a cyano group or more than one halogen atom as the case may be) Substituted) substituted pyrimidine-2,5-diyl, pyridine-2,5-diyl, 2,5-thienyl, 2,5-furanyl, 1,4- or 2,6-extended Naphthyl or phenylene, _R1 is a single bond, oxygen atom, -COO- or -OCO-, _R2 is a divalent aromatic group, a divalent alicyclic group, a divalent heterocyclic group or A 2-valent condensed ring group, _R3 is a single bond, an oxygen atom, -COO- or -OCO-, _R4 is a straight-chain or branched alkyl group with 1 to 40 carbons or a carbon containing alicyclic group A monovalent organic group with a number of 3 to 40, D represents an oxygen atom, a sulfur atom or -NR _d - (herein, R _d represents a hydrogen atom or an alkyl group with 1 to 3 carbons), and a represents 0 to 3 Integers, * represents the bonding position, X and Y are structures represented independently by a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group or an alkyl group with 1 to 3 carbons), if the aforementioned (A) component is When having a carboxyl group structure in the molecule, the aforementioned polymer is derived from the following formula (a-1-m) (wherein, I _a1 is a carboxyl group, r is ¹ or 2, S _a is a single bond, or a carbon Alkanediyl with 1~10 carbons, arylylene with 6~20 carbons, (*A)-CONH-R ₆ -(*B) or (*A)-COO-R ₇ -(*B) , M _a represents the following formula (M _a -1)~(M _a -2) (R ₁ represents a hydrogen atom or an alkyl group with 1 to 5 carbons, and * represents a bond), α-methylene Radical-polymerizable radicals of γ-butyrolactone, maleimide, norcamphene and their derivatives, or siloxane, R ₆ and R ₇ are independently single bonds, or carbon numbers 1 to 7 12 alkanediyl, arylylene group with 6~20 carbons, any carbon-carbon bond of alkanediyl can have -O-bond, (*A) means to bond with a carbon atom with an unsaturated bond (*B) represents the monomer that bonds with I _a1 ),

*-CH=CH-* (M _a -2). The liquid crystal alignment agent according to claim 1 or 2, wherein R in the aforementioned formula (pa-1) is a _monovalent organic group with 3 to 40 carbon atoms containing an alicyclic group. The liquid crystal alignment agent according to claim 2, wherein the aforementioned component (A) further has (A-3) a group selected from the group represented by oxetanyl group, oxirane group, and the following formula (3), The structure of at least one functional group of the group represented by the following formula (4), the group represented by the following formula (5), and the thioethylene group,

The liquid crystal alignment agent according to claim 2, wherein the aforementioned component (B) is a compound containing two or more epoxy groups or epithiol groups in the molecule. The liquid crystal alignment agent according to Claim 2, wherein the aforementioned component (B) is a compound containing two or more hydroxyalkylamide groups or benzyl alcohol groups in the molecule. Such as the liquid crystal alignment agent of claim 1 or 2, wherein, the monomer derived from the aforementioned (A-1) structure is contained in a ratio of 5 to 95 mol% relative to the polymer of the aforementioned (A) component, and 5 to A monomer component derived from the monomer of the aforementioned (A-2) structure was obtained at a ratio of 95 mol%. The liquid crystal alignment agent according to Claim 2, wherein 0.1 to 40 parts by mass of the above-mentioned (B) component is contained with respect to 100 parts by weight of the above-mentioned (A) component. The liquid crystal alignment agent according to Claim 1 or 2, wherein the aforementioned (A-2) is derived from the following formula (b-1-m) (wherein, M _c represents the second polymerizable group, M _d is selected from From a single bond, (r ² +1) valent heterocyclic ring, substituted or unsubstituted branched chain alkyl group with 1 to 10 carbons, or unsubstituted linear alkyl group with 1 to 10 carbons, (r ² + 1) valent aromatic group, (r ² + 1) valent alicyclic group, each group can be unsubstituted or one or more hydrogen atoms can be replaced by fluorine atom, chlorine atom, cyano group, Substituted by methyl or methoxy, S _b represents a single bond, a straight chain or branched chain with 1 to 10 carbons, a divalent aromatic group or a divalent alicyclic group, and I _b represents The group represented by formula (pa-1), r ² is an integer satisfying 1≦r ² ≦3), the monomer represented by

The liquid crystal alignment agent according to Claim 1 or 2, wherein the aforementioned (A-2) has the following formula (pa-1-a) (wherein, S _b is synonymous with formula (b-1-m), Z is an oxygen atom or a sulfur atom, X _a and X _b are independently a hydrogen atom, a fluorine atom, a chlorine atom, a cyano group or an alkyl group with 1 to 3 carbons, and _R1 is a single bond, an oxygen atom, or -COO -or-OCO-, _R2 is a divalent aromatic group, a divalent alicyclic group, or a divalent heterocyclic group, _R3 is a single bond, an oxygen atom, -COO- or -OCO-, _R4 is a linear or branched alkyl group with 1 to 40 carbons or a monovalent organic group with 3 to 40 carbons containing an alicyclic group, _R5 is an alkyl group with 1 to 3 carbons, 1~3 alkoxy group, fluorine atom or cyano group, a is an integer of 0~3, b is an integer of 0~4), the photo-alignment part represented by,

The liquid crystal alignment agent as claimed in item 10, wherein R in the aforementioned formula (pa-1-a) is a _monovalent organic group with 3 to 40 carbon atoms containing an alicyclic group. The liquid crystal alignment agent according to claim 1 or 2, wherein the aforementioned (A-1) is derived from the following formula (a-1-m) (wherein, I _a1 is selected from the group having at least one of the following formula (a2 ) or a monovalent organic group of a primary amino group, r ¹ is 1 or 2, S _a is a single bond or a divalent linking group, M _a is a first polymerizable group, but, The above-mentioned formula (a2) (in the formula, * represents the bonding position) represents the monomer other than the primary amino group),

The liquid crystal alignment agent as claimed in item 1 or 2, wherein the aforementioned (A-3) is derived from the following formula (c-1-m) (wherein, I _c is selected from the oxetane group in the molecule , an oxiranyl group, a group represented by the above formula (3), a group represented by the above formula (4), a group represented by the above formula (5), and a monovalent organic group, S _c represents a single bond or a divalent linking group, _Me represents a monomer represented by a third polymerizable group), _Me -S _c -I _c (c-1-m). The liquid crystal alignment agent according to claim 2, wherein the component (B) is an epoxy compound having at least one tertiary nitrogen atom in the molecule. Such as the liquid crystal alignment agent of claim 2, wherein, (B) component is at least one compound selected from the following formulas (2), [1] and [2], (wherein, X ₂ is a carbon number of 1 to 20 An aliphatic hydrocarbon group or an n-valent organic group containing an aromatic hydrocarbon group, n is an integer of 2 to 6, R ₂ and R ₃ are each independently a hydrogen atom, or an alkyl group with 1 to 4 carbons that may have a substituent , an alkenyl group with 2 to 4 carbons, or an alkynyl group with 2 to 4 carbons, at least one of R ₂ and R ₃ represents a hydrocarbon group substituted by a hydroxyl group, and Y ₁ , Y ₂ , and Y ₃ are independently Represents an aromatic ring, any hydrogen atom of the aromatic ring can be replaced by a hydroxyl group, an alkyl group with 1 to 3 carbon atoms, a halogen atom, an alkoxy group with 1 to 3 carbon atoms, or a vinyl group, and _Z1 is a single bond , a divalent saturated hydrocarbon group with 1 to 10 carbon atoms that can be bonded in whole or in part to form a ring structure, and any hydrogen atom can be replaced by a fluorine atom, -NH-, -N(CH ₃ )-, formula [3] (P ₁ and P ₂ are independently an alkyl group with 1 to 5 carbon atoms, Q ₁ represents an aromatic ring), t ₁ is an integer of 2 to 4, t ₂ and t ₃ are are independently integers of 1 to 3, a and b are independently integers of 1 to 3)

-P ₁ -Q ₁ -P ₂ - [3] . Such as the liquid crystal alignment agent of claim 1, wherein, the monomer derived from the aforementioned (A-1) site is contained in a ratio of 5 to 94 mol % relative to the entire polymer of the aforementioned (A) component, and 5 to 94 mol The proportion of the monomer derived from the aforementioned (A-2) part, the proportion of 1 to 40mol% of the aforementioned (A-3) derived part It is obtained from the monomer component formed by the monomer of the position. The liquid crystal alignment agent according to claim 1 or 2, wherein the weight average molecular weight of the polymer of the aforementioned component (A) is 2,000-1,000,000. A liquid crystal alignment film formed by using the liquid crystal alignment agent of claim 1 or 2. A method for manufacturing a liquid crystal alignment film, which includes the steps of applying the liquid crystal alignment agent of claim 1 or 2 onto a substrate to form a coating film, and the aforementioned coating film is in a state where it is not in contact with the liquid crystal layer or is in contact with the liquid crystal layer. A step of irradiating the aforementioned coating film with light in a state of being in contact. A liquid crystal display element comprising the liquid crystal alignment film of claim 18 or the liquid crystal alignment film obtained by the manufacturing method of claim 19.