CN118667558A

CN118667558A - Liquid crystal aligning agent, liquid crystal alignment film and method for producing the same, liquid crystal element and method for producing the same

Info

Publication number: CN118667558A
Application number: CN202410271360.9A
Authority: CN
Inventors: 铃木一圣; 安池伸夫
Original assignee: JSR Corp
Current assignee: Jicc 02 Co ltd
Priority date: 2023-03-20
Filing date: 2024-03-11
Publication date: 2024-09-20
Also published as: TW202438652A; JP2024134142A

Abstract

The invention provides a liquid crystal aligning agent, a liquid crystal aligning film and a manufacturing method thereof, and a liquid crystal element and a manufacturing method thereof, wherein the liquid crystal aligning agent can obtain a liquid crystal aligning film with excellent impurity resistance and sealing adhesion, and can obtain a liquid crystal element with good transmittance. A liquid crystal aligning agent comprises a polymer (P1), wherein the polymer (P1) has a partial structure (a 1) represented by the formula (1) and a partial structure (a 2) which is a specific nitrogen-containing structure in the same molecule or in different molecules. In formula (1), R ¹ and R ² are monovalent substituents. n1 and n2 are 0 or 1. m1 is an integer of 0 to (n1x2+4). m2 is an integer of 0 to (n2×2+4).

Description

Liquid crystal aligning agent, liquid crystal alignment film and method for producing the same, liquid crystal element and method for producing the same

Technical Field

The invention relates to a liquid crystal aligning agent, a liquid crystal alignment film and a manufacturing method thereof, a liquid crystal element and a manufacturing method thereof.

Background

Conventionally, as liquid crystal elements, various driving schemes have been developed, such as a twisted nematic (TWISTED NEMATIC, TN) type, super twisted nematic (Super TWISTED NEMATIC, STN) type, vertical alignment (VERTICAL ALIGNMENT, VA) type, multi-domain vertical alignment (Multi-domain VERTICAL ALIGNMENT, MVA) type, in-plane switching (IPS (In-PLANE SWITCHING) type), fringe field switching (FRINGE FIELD SWITCHING, FFS) type, optical compensation bending type (OCB (Optically Compensated Bend)) type, and polymer stable alignment (Polymer Sustained Alignment, PSA) type, which are different from each other In physical properties of liquid crystal molecules used. These liquid crystal elements have a liquid crystal alignment film for aligning liquid crystal molecules. The liquid crystal alignment film is generally formed on a substrate by applying a liquid crystal alignment agent, which is obtained by dissolving or dispersing a polymer component in an organic solvent, to the surface of the substrate, preferably by heating.

In recent years, a large-screen and high-definition liquid crystal television has become a main body, and a small-sized display terminal such as a smart phone or a tablet personal computer (personal computer, PC) has become popular, and a demand for a liquid crystal element having a higher quality has been further increased. In order to meet such a demand for higher quality, various liquid crystal aligning agents have been proposed (for example, see patent document 1 or patent document 2). Patent document 1 discloses that a liquid crystal alignment film is formed using a polymer obtained by reacting a diamine compound containing a diamine having a fluorene structure with a tetracarboxylic dianhydride. Patent document 2 discloses a crosslinkable compound which is a low molecular compound for improving the hardness of a liquid crystal alignment film, and which contains polyimide or a polyimide precursor together with a liquid crystal alignment agent.

[ Prior Art literature ]

[ Patent literature ]

[ Patent document 1] Japanese patent laid-open No. 2002-155138

[ Patent document 2] International publication No. 2020/171128

Disclosure of Invention

[ Problem to be solved by the invention ]

With the high definition of liquid crystal elements, the requirements for quality become more stringent. For example, an insulating film is often provided on a high-definition liquid crystal panel such as 4K or 8K, and in a liquid crystal panel provided with an insulating film, ionic impurities from the insulating film may be eluted into liquid crystal through a liquid crystal alignment film. When ionic impurities are eluted into the liquid crystal, the quality of the liquid crystal element may be lowered, such as a decrease in voltage holding ratio. Therefore, a liquid crystal alignment film is required to have a performance (hereinafter, also referred to as "impurity resistance") of suppressing intrusion of impurities generated in an element into a liquid crystal and suppressing a decrease in voltage holding ratio due to the impurities. In addition, in a high-definition liquid crystal panel, the occupancy of a Black Matrix (BM), a thin film transistor (Thin Film Transistor, TFT), or the like increases. Therefore, the importance of the improvement in transmittance at the opening of the panel increases.

High-definition liquid crystal elements are required to have not only improved impurity resistance and transmittance but also excellent mechanical properties of liquid crystal alignment films and adhesion to substrates. For example, in view of design and miniaturization of display devices, in addition to mobile applications represented by smartphones, tablet PCs, and the like, a narrow frame is being realized in a large-sized television or a monitor for a PC. As one of methods for realizing a narrow frame, a method is known in which a liquid crystal alignment film is formed on the entire substrate surface, and then a sealant is applied to the liquid crystal alignment film to bond the substrates to each other. On the other hand, when the sealant is disposed on the liquid crystal alignment film, a force is easily applied to the portion where the sealant is disposed. Therefore, when the mechanical strength of the liquid crystal alignment film or the adhesion to the substrate is insufficient, there is a concern that: the adhesion between substrates (hereinafter, also referred to as "sealing adhesion") is reduced, and peeling of the substrates is likely to occur due to external force or the like.

The present invention has been made in view of the above problems, and a main object of the present invention is to provide a liquid crystal aligning agent which can provide a liquid crystal alignment film excellent in impurity resistance and sealing adhesion and can provide a liquid crystal element excellent in transmittance.

[ Means of solving the problems ]

The present inventors have studied to achieve further improvement in quality of a liquid crystal element, and have found that the above problems can be solved by improving the composition of a liquid crystal aligning agent. Specifically, the present invention provides the following means.

[ 1] A liquid crystal aligning agent comprising a polymer (P1), wherein the polymer (P1) has a partial structure (a 1) represented by the following formula (1) and a partial structure (a 2) represented by the following formula (1) in the same molecule or in different molecules.

[ Chemical 1]

( In the formula (1), R ¹ and R ² are independent monovalent substituents; n1 and n2 are independently 0 or 1; m1 is an integer of 0 to (n1x2+4); m2 is an integer of 0 to (n2x2+4); where multiple R ¹ are present, multiple R ¹ are the same or different, and where multiple R ² are present, multiple R ² are the same or different; "A" means a bond to a carbon atom )

Partial structure (a 2): at least one selected from the group consisting of a nitrogen-containing heterocyclic structure, a partial structure represented by the following formula (2), and a partial structure represented by the following formula (3)

[ Chemical 2]

( In the formula (2), Y ¹ is a hydrogen atom or a monovalent group which is detached by heating and substituted for the hydrogen atom; a ¹ is an alkanediyl group, a substituted or unsubstituted divalent alicyclic group, or a substituted or unsubstituted divalent aromatic ring group; a ² is alkanediyl; "x" means bond )

[ Chemical 3]

( In the formula (3), Y ² is a monovalent group which is detached by heating and which substitutes a hydrogen atom; x ³ is a single bond or an alkanediyl group; r ⁴ and R ⁵ are each independently a hydrogen atom or a monovalent hydrocarbon group; "x" means bond )

[ 2 ] A liquid crystal aligning agent comprising a polymer having a partial structure (a 1) represented by the above formula (1), and at least one compound selected from the group consisting of-OE ¹ groups (wherein E ¹ is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms OR a monovalent releasing group), mercapto groups, protected mercapto groups, amino groups, protected amino groups, oxetanyl groups and-Si (groups represented by OR ¹¹)_r(R¹²)₃-_r) (wherein R ¹¹ and R ¹² are each independently a monovalent hydrocarbon group having 1 to 10 carbon atoms, R is an integer of 1 to 3, and R ¹¹ are the same OR different when R is 2 OR 3, and R ¹² are the same OR different when R is 1), and a polymerizable carbon-carbon double bond group, wherein the polymer has a total of 2 OR more groups in one molecule.

The liquid crystal alignment film according to [ 3 ] is formed by using the liquid crystal alignment agent according to [1] or [ 2 ].

A liquid crystal element comprising the liquid crystal alignment film according to [3 ].

[ 5 ] A method for producing a liquid crystal alignment film, comprising: a step of forming a coating film by using the liquid crystal aligning agent according to [ 1 ] or [ 2 ]; and a step of applying a liquid crystal aligning ability to the coating film by irradiating the coating film with light.

[ 6 ] A method for manufacturing a liquid crystal element, comprising:

a step of forming a coating film on each of the conductive films of the pair of substrates having the conductive film by using the liquid crystal aligning agent according to the item [ 1 ] or [ 2 ]; a step of disposing a pair of substrates on which the coating film is formed, with a liquid crystal layer containing a photopolymerizable compound interposed therebetween, so that the coating film faces each other, thereby constructing a liquid crystal cell; and a step of irradiating the liquid crystal cell with light in a state where a voltage is applied between the conductive films.

[ Effect of the invention ]

The liquid crystal alignment agent of the present invention can provide a liquid crystal alignment film excellent in impurity resistance and sealing adhesion. In addition, a liquid crystal element having excellent transmittance can be obtained by forming a liquid crystal alignment film from the liquid crystal alignment agent of the present invention.

Detailed Description

Liquid Crystal alignment agent

The liquid crystal aligning agent of the present disclosure contains a polymer having a partial structure (a 1) represented by the following formula (1).

[ Chemical 4]

In the present disclosure, specific modes of the liquid crystal aligning agent containing the polymer having the partial structure (a 1) include the following first liquid crystal aligning agent and second liquid crystal aligning agent.

First liquid crystal aligning agent: the liquid crystal aligning agent contains a polymer (hereinafter, also referred to as "polymer (P1)") having a partial structure (a 1) represented by the above formula (1) and a partial structure (a 2) shown below in the same molecule or in different molecules.

[ Chemical 5]

[ Chemical 6]

Second liquid crystal aligning agent: a liquid crystal aligning agent comprising a polymer having a partial structure (A1) represented by the above formula (1) (hereinafter, also referred to as "polymer (P2)") and at least one compound (hereinafter, also referred to as "compound (A1)") selected from the group consisting of a group represented by-OE ¹, wherein E ¹ is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms OR a monovalent releasing group, a mercapto group, a protected mercapto group, an amino group, a protected amino group, an oxetanyl group, and a group represented by Si (OR ¹¹)_r(R¹²)_3-r), wherein R ¹¹ and R ¹² are each independently a monovalent hydrocarbon group having 1 to 10 carbon atoms, R is an integer of 1 to 3, and when R is 2 OR 3, a plurality of R ¹¹ are the same OR different, and when R is 1, a plurality of R ¹² are the same OR different), and a polymerizable carbon-carbon double bond group.

The first liquid crystal aligning agent and the second liquid crystal aligning agent can obtain a liquid crystal alignment film with excellent impurity resistance and sealing adhesion, and can obtain a liquid crystal element with good transmittance. Hereinafter, each component contained in the first liquid crystal aligning agent and the second liquid crystal aligning agent, and other components optionally blended, will be described. Further, as for each component, one kind may be used alone, or two or more kinds may be used in combination, unless otherwise mentioned.

In the present specification, the term "hydrocarbon group" means a hydrocarbon group including a chain hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group. The term "chain hydrocarbon group" means a straight chain hydrocarbon group and a branched hydrocarbon group which do not contain a cyclic structure in the main chain but contain only a chain structure. Wherein, the chain hydrocarbon group can be saturated or unsaturated. The term "alicyclic hydrocarbon group" means a hydrocarbon group having a ring structure containing only alicyclic hydrocarbon, but not having an aromatic ring structure. The alicyclic hydrocarbon group does not need to have a structure containing only alicyclic hydrocarbon, and may contain a group having a chain structure in a part thereof. The term "aromatic hydrocarbon group" means a hydrocarbon group having an aromatic ring structure as a ring structure. The aromatic hydrocarbon group need not contain only an aromatic ring structure, but may contain a chain structure or an alicyclic hydrocarbon structure in a part thereof. The term "aromatic ring" is intended to include aromatic hydrocarbon rings and aromatic heterocyclic rings. The term "organic group" refers to an atomic group obtained by removing any hydrogen atom from a carbon-containing compound (i.e., an organic compound).

The "main chain" of the polymer means a portion of the "backbone" of the polymer that contains the longest chain of atoms. The "backbone" portion may be allowed to include a ring structure. For example, the term "having a specific structure in the main chain" means that the specific structure forms a part of the main chain. The term "side chain" refers to a portion branched from a portion of the "backbone" of the polymer. "(meth) acryl" is a term including acryl and methacryl, and "(meth) acrylate" is a term including acrylate and methacrylate. The group which is released by heating and which substitutes for a hydrogen atom is also referred to as a "heat-releasable group".

[ First liquid Crystal alignment agent ]

< Polymer (P1) >

Partial structure (a 1)

In the formula (1), examples of the monovalent substituent represented by R ¹ or R ² include: alkyl group having 1 to 12 carbon atoms, alkoxy group having 1 to 12 carbon atoms, halogen atom (for example, fluorine atom, chlorine atom, bromine atom, iodine atom, etc.), halogenated alkyl group having 1 to 12 carbon atoms, halogenated alkoxy group having 1 to 12 carbon atoms, hydroxyl group, etc. The 2 bonding bonds in the formula (1) may be bonded to carbon atoms constituting the main chain of the polymer (P1) or may be bonded to carbon atoms constituting the side chain.

In terms of obtaining a liquid crystal alignment film having higher sealing adhesion and forming a film having high impurity resistance, the 2 bonding bonds (x) in the formula (1) are preferably bonded to aromatic rings (preferably, different aromatic rings) respectively. Specifically, the polymer (P1) preferably includes at least one partial structure selected from the group consisting of a partial structure represented by the following formula (1-1) and a partial structure represented by the following formula (1-2) as the structure having the partial structure (a 1) represented by the following formula (1).

[ Chemical 7]

( In the formula (1-1) and the formula (1-2), ar ¹ and Ar ² are independently a divalent aromatic ring group; x ¹ and X ² are independently an alkanediyl group having 1 to 10 carbon atoms which is a single bond 、-O-、-S-、-CO-、-NR⁸-、-COO-、-CONR⁸-、-NR⁸CONR⁹-、-SO₂-、-SO₂-O-、 or any methylene group in an alkanediyl group having 2 to 10 carbon atoms is substituted with a group obtained by-O-, -S-, -CO-, -NR ⁸-、-COO-、-OCO-、-CONR⁸-、-NR⁸ CO-or-NR ⁸CONR⁹ -; r ⁸ and R ⁹ are each independently a hydrogen atom or a monovalent organic group; ar ³ and Ar ⁴ are independently trivalent aromatic ring groups; r ¹、R², n1, n2, m1 and m2 have the same meaning as in the above formula (1); "x" means bond )

In the above formula (1-1) and formula (1-2), the divalent aromatic ring group represented by Ar ¹ or Ar ² is a group in which 2 hydrogen atoms are removed from the ring portion of the substituted or unsubstituted aromatic ring. Examples of the aromatic ring include: aromatic hydrocarbon rings such as benzene ring, naphthalene ring and anthracene ring; nitrogen-containing aromatic heterocyclic rings such as pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring and imidazole ring; sulfur-containing aromatic heterocyclic rings such as thiophene rings, and the like. When the aromatic ring has a substituent, examples of the substituent include: alkyl group having 1 to 5 carbon atoms, alkoxy group having 1 to 5 carbon atoms, halogenated alkyl group having 1 to 5 carbon atoms, halogenated alkoxy group having 1 to 5 carbon atoms, alkoxyalkyl group having 1 to 5 carbon atoms, alkoxyalkoxyalkyl group having 1 to 5 carbon atoms, halogen atom, hydroxyl group, etc.

Among these, ar ¹ and Ar ² are preferably groups in which 2 hydrogen atoms are removed from the ring portion of a substituted or unsubstituted aromatic hydrocarbon ring, and more preferably groups in which 2 hydrogen atoms are removed from the ring portion of a substituted or unsubstituted benzene ring, from the viewpoints of improving the effect of improving the sealing adhesion, forming a film having high impurity resistance, and easiness of obtaining a monomer.

When X ¹ or X ² has-NR ⁸-、-CONR⁸ -or-NR ⁸CONR⁹ -, examples of the monovalent organic group represented by R ⁸ or R ⁹ include a monovalent hydrocarbon group having 1 to 10 carbon atoms and a monovalent heat-releasable group. In the case where R ⁸ or R ⁹ is a monovalent hydrocarbon group having 1 to 10 carbon atoms, examples of the hydrocarbon group include: alkyl groups having 1 to 10 carbon atoms, monovalent alicyclic hydrocarbon groups having 3 to 10 carbon atoms, monovalent aromatic hydrocarbon groups having 5 to 10 carbon atoms, and the like. Of these, alkyl groups having 1 to 5 carbon atoms, cyclohexyl groups, or phenyl groups are preferable, and alkyl groups having 1 to 3 carbon atoms are more preferable. The monovalent heat-releasable group is a group that is released by heat application and that replaces a hydrogen atom. In terms of high heat release property, the heat release group represented by R ⁸ or R ⁹ is preferably t-butoxycarbonyl (Boc group).

In view of making the sealing adhesion more excellent, in the above, X ¹ and X ² are preferably a single bond, -O-or-CONR ⁸ -, more preferably-O-or-CONR ⁸ -. In order to obtain a liquid crystal alignment film having more excellent impurity resistance and mechanical strength, the bond on the opposite side to Ar ¹ in X ¹ and the bond on the opposite side to Ar ² in X ² are preferably bonded to an aromatic ring. Specific examples and preferred examples of the aromatic ring include the same examples as those described in the description of Ar ¹ and Ar ².

The trivalent aromatic ring group represented by Ar ³ or Ar ⁴ is a group obtained by removing 3 hydrogen atoms from the ring portion of a substituted or unsubstituted aromatic ring. Specific examples and preferred examples of the aromatic ring include the same examples as the divalent aromatic ring groups of Ar ¹ and Ar ². Among these, ar ³ and Ar ⁴ are preferably groups in which 3 hydrogen atoms are removed from the ring portion of a substituted or unsubstituted aromatic hydrocarbon ring, and more preferably groups in which 3 hydrogen atoms are removed from the ring portion of a substituted or unsubstituted benzene ring, from the viewpoint of improving the effect of improving the sealing adhesion or from the viewpoint of easiness in obtaining a monomer.

Specific examples of the partial structure including the partial structure (a 1) included in the polymer (P1) include the partial structures represented by the following formulas (1-1) to (1-11).

[ Chemical 8]

(In the formulae (1-1) to (1-11), "x" represents a bond

From the viewpoint of ease of introduction into the partial structure (a 1), the polymer (P1) preferably contains a structural unit derived from a single unit having the partial structure (a 1). The content of the structural unit derived from the monomer having the partial structure (a 1) in the polymer (P1) is preferably 0.5 mol% or more, more preferably 1 mol% or more, and still more preferably 2 mol% or more, based on the total amount of the structural units constituting the polymer (P1). The content of the structural unit derived from the monomer having the partial structure (a 1) is preferably 40 mol% or less, more preferably 30 mol% or less, and still more preferably 25 mol% or less, based on the total amount of the structural units constituting the polymer (P1).

Partial structure (a 2)

(Structure of nitrogen-containing heterocycle)

The partial structure (a 2) has a specific nitrogen-containing structure. It is considered that, in a liquid crystal element having a liquid crystal alignment film formed of the first liquid crystal alignment agent, since the polymer (P1) has a specific nitrogen-containing structure, impurities originating from an insulating film or the like are adsorbed by the liquid crystal alignment film and remain in the film, and the effect of suppressing the invasion of impurities into the liquid crystal layer is improved, whereby the reduction in voltage holding ratio due to the generation of impurities can be further suppressed.

In the case where the polymer (P1) has a nitrogen-containing heterocyclic structure as the partial structure (a 2), the nitrogen-containing heterocyclic ring in the nitrogen-containing heterocyclic structure may be an aromatic heterocyclic ring or a non-aromatic heterocyclic ring. In addition, the nitrogen-containing heterocycle may be a monocyclic ring or a condensed ring. Specific examples of the nitrogen-containing aromatic heterocycle include: pyrrole ring, imidazole ring, pyrazole ring, triazole ring, pyridine ring, pyrimidine ring, pyridazine ring, quinoline ring, benzimidazole ring, carbazole ring, and pyrazine ring, and heterocyclic ring having a substituent (e.g., methyl, ethyl, etc.) on these rings. Examples of the nitrogen-containing non-aromatic heterocycle include: piperidine ring, piperazine ring, morpholine ring, and hexamethyleneimine ring, and heterocyclic rings obtained by introducing substituents (for example, methyl group, ethyl group, etc.) into these rings. Preferably a pyridine ring, a benzimidazole ring, a carbazole ring, a piperidine ring or a piperazine ring.

Of these, the nitrogen-containing heterocyclic ring of the partial structure (a 2) is preferably at least one selected from the group consisting of a pyridine ring, a pyrimidine ring, a pyrazine ring, a piperidine ring, a piperazine ring, a quinoline ring, and a benzimidazole ring. Among these, pyridine rings are preferable because nitrogen-containing heterocycles exhibit strong basicity.

In the case where the polymer (P1) has a nitrogen-containing heterocyclic structure as the partial structure (a 2), the polymer (P1) may have a nitrogen-containing heterocyclic structure in the main chain, may have a nitrogen-containing heterocyclic structure in the side chain, or may have a nitrogen-containing heterocyclic structure in both the main chain and the side chain.

Specific examples of the nitrogen-containing heterocyclic structure include partial structures represented by the following formulae (2 a-1) to (2 a-10). In the formula, "Boc" represents a tert-butoxycarbonyl group (the same applies hereinafter).

[ Chemical 9]

(In the formulae (2 a-1) to (2 a-10), ", represents a bond

(The partial Structure represented by the formula (2))

In the formula (2), Y ¹ is a hydrogen atom or a heat-releasable group. Examples of the heat-peelable group include: urethane-based releasable groups, amide-based releasable groups, imide-based releasable groups, sulfonamide-based releasable groups, and the like. Among these, urethane-based releasable groups are preferable in terms of high release properties by heat. Specific examples thereof include: tert-butoxycarbonyl, benzyloxycarbonyl, 1-dimethyl-2-halogenated ethyloxycarbonyl, allyloxycarbonyl, 2- (trimethylsilyl) ethoxycarbonyl, 9-fluorenylmethyloxycarbonyl (F-moc group) and the like. Among these, tert-butoxycarbonyl (Boc group) is particularly preferred in terms of excellent heat-based releasability and reduced residual amount of the deprotected moiety in the film.

The alkanediyl group represented by a ¹ or a ² may be linear or branched. The alkanediyl group represented by a ¹ or a ² is preferably linear from the viewpoint of obtaining a liquid crystal alignment film having more excellent sealing adhesion. The alkanediyl group represented by a ¹ or a ² has, for example, 1 to 10 carbon atoms. The alkanediyl group represented by a ¹ or a ² is preferably a carbon number of 1 to 6, more preferably a carbon number of 1 to 4, and still more preferably a carbon number of 1 or 2, from the viewpoint of improving the sealing adhesion of the liquid crystal alignment film.

In the case where a ¹ is a substituted or unsubstituted divalent alicyclic group, examples of the alicyclic group include: cyclopentanediyl group, cyclohexanediyl group, and groups obtained by introducing a substituent into these groups. In the case where a ¹ is a substituted or unsubstituted divalent aromatic ring group, the aromatic ring group is preferably a phenylene group, a pyridyldiyl group, or a group in which a substituent is introduced into these groups. In the case where a ¹ is a substituted divalent alicyclic group or aromatic ring group, the same groups as those exemplified as substituents which may be present in the divalent aromatic ring group represented by Ar ¹ or Ar ² can be used as substituents.

When the polymer (P1) has the partial structure represented by the formula (2) as the partial structure (a 2), the polymer (P1) may have the partial structure represented by the formula (2) in the main chain, may have the partial structure represented by the formula (2) in the side chain, or may have the partial structure represented by the formula (2) in both the main chain and the side chain. In order to obtain a liquid crystal alignment film having more excellent impurity resistance, it is preferable to introduce a partial structure represented by the formula (2) into the main chain of the polymer (P1).

When the polymer (P1) has a partial structure represented by the above formula (2), specific examples of the partial structure of the polymer (P1) include the partial structures represented by the following formulas (2 b-1) to (2 b-7). In the formula, "F-moc" represents 9-fluorenylmethoxycarbonyl (the same applies hereinafter).

[ Chemical 10]

(In the formulae (2 b-1) to (2 b-7), ", represents a bond

In the case where the polymer (P1) has the partial structure represented by the formula (2 b-7), the polymer (P1) corresponds to a polymer having a nitrogen-containing heterocyclic structure and the partial structure represented by the formula (2) as the partial structure (a 2).

(The partial Structure represented by the formula (3))

In the formula (3), Y ² is a heat-releasable group. The same groups as those exemplified as specific examples in the description of Y ¹ in the above formula (2) are exemplified. The t-butoxycarbonyl group (Boc group) is preferable in terms of excellent heat-based releasability and reduced residual amount of the deprotected moiety in the film.

The alkanediyl group represented by X ³ is preferably a carbon number of 1 to 6, more preferably a carbon number of 1 to 4, and still more preferably a carbon number of 1 or 2. The alkanediyl group represented by X ³ may be linear or branched, and is preferably linear. Among them, X ³ is preferably a single bond or an alkanediyl group having 1 to 4 carbon atoms, more preferably a single bond, a methylene group or an ethylene group.

Examples of the monovalent hydrocarbon group represented by R ⁴ or R ⁵ include: a chain hydrocarbon group having 1 to 10 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, or an aromatic hydrocarbon group having 6 to 12 carbon atoms. R ⁴ and R ⁵ are preferably a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms.

When the polymer (P1) has a partial structure represented by the above formula (3), specific examples of the partial structure of the polymer (P1) include the partial structures represented by the following formulas (2 c-1) to (2 c-8).

[ Chemical 11]

(In the formulae (2 c-1) to (2 c-8), ", represents a bond

From the viewpoint of ease of introduction of the partial structure (a 2) into the main chain, the polymer (P1) preferably contains a structural unit derived from a single unit having the partial structure (a 2). The content of the structural unit derived from the monomer having the partial structure (a 2) in the polymer (P1) is preferably 0.5 mol% or more, more preferably 1 mol% or more, and still more preferably 2 mol% or more, based on the total amount of the structural units constituting the polymer (P1). The content of the structural unit derived from the monomer having the partial structure (a 2) is preferably 50 mol% or less, more preferably 45 mol% or less, and still more preferably 40 mol% or less, based on the total amount of the structural units constituting the polymer (P1).

The polymer (P1) contains the partial structure (a 1) and the partial structure (a 2) in the same molecule or in different molecules. Specific modes of the first liquid crystal aligning agent containing the polymer (P1) include the following modes 1 and 2.

The embodiment 1 includes a polymer having a partial structure (a 1) and a partial structure (a 2) in the same molecule (hereinafter, also referred to as a "first polymer (P11)") as the embodiment of the polymer (P1).

The embodiment 2 includes a polymer having a partial structure (a 1) (hereinafter, also referred to as "second polymer (P12)") and a polymer different from the second polymer (hereinafter, also referred to as "third polymer (P13)") as the polymer (P1).

Among these, embodiment 1 is preferable in that a liquid crystal alignment film excellent in impurity resistance and sealing adhesion can be obtained by using as few components as possible, and a liquid crystal element excellent in transmittance can be obtained.

In addition, when the polymer (P1) is composed of a plurality of polymers, the ratio of the structural units derived from the single unit having the partial structure (a 1) and the ratio of the structural units derived from the single unit having the partial structure (a 2) in the polymer (P1) represent the total ratio of the plurality of polymers. For example, in the case where the first liquid crystal aligning agent contains the second polymer (P12) and the third polymer (P13) as the polymer (P1), the sum of the proportion of the structural units derived from the monomer having the partial structure (a 1) in the second polymer (P12) and the proportion of the structural units derived from the monomer having the partial structure (a 1) in the third polymer (P13) is the proportion of the structural units derived from the monomer having the partial structure (a 1) in the polymer (P1).

The main skeleton of the polymer (P1) is not particularly limited. Examples of the main skeleton of the polymer (P1) include: polyamide acids, polyamide acid esters, polyimides, polyamines, polyalkenamines (polyenamine), polyureas, polyorganosiloxanes, polyesters, polyamides, polyamideimides, polybenzoxazole precursors, polybenzoxazoles, cellulose derivatives, polyacetals, addition polymers, and the like. The addition polymer is a polymer obtained by polymerizing a monomer having a polymerizable unsaturated carbon-carbon bond (addition polymerization), and examples thereof include: (meth) acrylic polymers, styrene polymers, maleimide polymers, styrene-maleimide copolymers, and the like. The polyalkene amine is a polymer having a carbon-carbon double bond at the adjacent position of the amino group of the polyamine, and examples thereof include: polyalkenyl ketone, polyalkenyl ester, polyalkenyl nitrile, polyalkenyl sulfonyl, and the like.

The polymer (P1) is preferably a polymer containing a structural unit derived from a diamine compound in terms of affinity with liquid crystal molecules, mechanical strength, liquid crystal alignment, and easiness of introduction of the partial structure (a 1) and the partial structure (a 2). Specific examples of such a polymer (P1) include: polyamic acid, polyamic acid ester, polyimide, polyamide, polyalkene amine, polyamideimide, and the like. Among them, the polymer (P1) is preferably at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide.

The method for producing the polyamic acid, polyamic acid ester, and polyimide as the polymer (P1) is not particularly limited, and can be produced by appropriately combining conventional methods of organic chemistry. Specific examples of the method for producing the polymer (P1) include: a method of reacting a tetracarboxylic dianhydride with a diamine compound containing a diamine having a partial structure (a 1) (hereinafter, also referred to as "first specific diamine") and a diamine having a partial structure (a 2) (hereinafter, also referred to as "second specific diamine"); (II) a method of reacting a tetracarboxylic dianhydride having the partial structure (a 1) (hereinafter, also referred to as "specific acid dianhydride") with a diamine compound containing a second specific diamine; a method in which the method [ I ] is combined with the method [ II ], and the like. The polyamide acid, polyamide acid ester and polyimide as the polymer (P1) will be described in detail below.

(Polyamic acid)

Tetracarboxylic dianhydride

Specific acid dianhydrides that can be used in synthesizing the polyamic acid (hereinafter, also referred to as "polyamic acid (P1)") as the polymer (P1) include tetracarboxylic dianhydrides having the partial structure represented by the formula (1-1) and tetracarboxylic dianhydrides having the partial structure represented by the formula (1-2). Specific examples of the specific acid dianhydride include compounds represented by the following formulae (t 1-1) to (t 1-4).

[ Chemical 12]

In the synthesis of the polyamic acid (P1), tetracarboxylic dianhydride (hereinafter, also referred to as "other acid dianhydride") having no partial structure (a 1) may be used alone or together with a specific acid dianhydride. Examples of the other acid dianhydride include aliphatic tetracarboxylic acid dianhydride and aromatic tetracarboxylic acid dianhydride. The aliphatic tetracarboxylic dianhydride includes a chain tetracarboxylic dianhydride and an alicyclic tetracarboxylic dianhydride.

Specific examples of the chain tetracarboxylic dianhydride include butane tetracarboxylic dianhydride and the like. Specific examples of the alicyclic tetracarboxylic dianhydride include: 1,2,3, 4-cyclobutanetetracarboxylic dianhydride, 1, 3-dimethyl-1, 2,3, 4-cyclobutanetetracarboxylic dianhydride, 2,3, 5-tricarboxyl cyclopentylacetic anhydride, 5- (2, 5-dioxotetrahydrofuran-3-yl) -3a,4,5,9 b-tetrahydronaphtho [1,2-c ] furan-1, 3-dione, 5- (2, 5-dioxotetrahydrofuran-3-yl) -8-methyl-3 a,4,5,9 b-tetrahydronaphtho [1,2-c ] furan-1, 3-dione, 3-oxabicyclo [3.2.1] octane-2, 4-dione-6-spiro-3 ' - (tetrahydrofuran-2 ',5' -dione), 5- (2, 5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1, 2-dicarboxylic anhydride, 3,5, 6-tricarboxyl-2-carboxymethyl norbornane-2: 3,5: 6-dianhydride, bicyclo [3.3.0] octane-2, 4,6, 8-tetracarboxylic acid 2:4,6: 8-dianhydride, bicyclo [2.2.1] heptane-2, 3,5, 6-tetracarboxylic acid 2:3,5: 6-dianhydride, 4, 9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane-3, 5,8, 10-tetraketone, 1,2,4, 5-cyclohexane tetracarboxylic dianhydride, bicyclo [2.2.2] oct-7-ene-2, 3,5, 6-tetracarboxylic dianhydride, ethylenediamine tetraacetic dianhydride, cyclopentane tetracarboxylic dianhydride, and the like.

Examples of the aromatic tetracarboxylic dianhydride include: pyromellitic dianhydride, 4'- (hexafluoroisopropylidene) diphthalic anhydride, p-phenylene bis (trimellitic monoester anhydride), ethylene glycol bis (trimellitic anhydride ester), 1, 3-propanediol bis (trimellitic anhydride ester), 3',4 '-benzophenone tetracarboxylic dianhydride, 4' -diphthalic dianhydride, and the like. In addition, as the tetracarboxylic dianhydride used for the synthesis of the polyamic acid (P1), a tetracarboxylic dianhydride described in japanese patent application laid-open No. 2010-97188, or the like may be used in addition to the above.

In the case where the liquid crystal aligning ability is imparted to the organic film formed of the first liquid crystal aligning agent by the photo-alignment treatment, it is preferable to use a substituted cyclobutane tetracarboxylic dianhydride in the synthesis of the polymer (P1) in terms of further improving the photoreactivity of the organic film. Specific examples of the substituted cyclobutane tetracarboxylic dianhydride include compounds represented by the following formulae (t 2-1) to (t 2-6).

[ Chemical 13]

When the specific acid dianhydride is used in the synthesis of the polyamic acid (P1), the specific acid dianhydride is preferably used in a proportion of 1 mol% or more, more preferably 2 mol% or more, and still more preferably 5 mol% or more, based on the total amount of the tetracarboxylic dianhydride used in the synthesis of the polyamic acid (P1). The specific acid dianhydride is used in a proportion of preferably 50 mol% or less, more preferably 40 mol% or less, and still more preferably 30 mol% or less, based on the total amount of the tetracarboxylic dianhydride used for the synthesis of the polyamic acid (P1). In addition, the blending ratio of the monomers used for the synthesis of the polymer is the same as the ratio of the monomer units constituting the obtained polymer with respect to the polyamic acid, polyamic acid ester, and polyimide.

When the substituted cyclobutane tetracarboxylic dianhydride is used in the synthesis of the polyamic acid (P1), the use ratio of the substituted cyclobutane tetracarboxylic dianhydride is preferably 10 mol% or more with respect to the total amount of the tetracarboxylic dianhydrides used in the synthesis of the polyamic acid (P1) in terms of sufficiently improving the photoreactivity of the coating film. More preferably 30 mol% or more, and still more preferably 50 mol% or more.

Diamine compound

As the first specific diamine that can be used in synthesizing the polyamic acid (P1), a diamine having a partial structure represented by the formula (1-1) may be preferably used. Preferable specific examples of the first specific diamine include a compound represented by the following formula (D1).

[ Chemical 14]

( In the formula (D1), R ¹、R², n1, n2, m1 and m2 have the same meaning as in the formula (1); ar ¹、Ar²、X¹ and X ² are as defined for formula (1-1); r ⁶ and R ⁷ are independently a single bond or a divalent aromatic ring group; wherein X ¹ is a single bond or an alkanediyl group having 1 to 10 carbon atoms when R ⁶ is a single bond, and X ² is a single bond or an alkanediyl group having 1 to 10 carbon atoms when R ⁷ is a single bond )

Further specific examples of the first specific diamine include compounds represented by the following formulae (d 1-1) to (d 1-20).

[ 15]

[ 16]

The second specific diamine that can be used in synthesizing the polyamic acid (P1) may preferably use a compound having 2 primary diamines and at least one selected from the group consisting of a nitrogen-containing heterocyclic structure, a partial structure represented by the formula (2), and a partial structure represented by the formula (3). Specific examples of the second specific diamine include compounds represented by the following formulae (d 2-1) to (d 2-31).

[ Chemical 17]

[ Chemical 18]

In the synthesis of the polyamic acid (P1), a diamine (hereinafter, also referred to as "other diamine") having neither the partial structure (a 1) nor the partial structure (a 2) may be used. As the other diamine, an existing diamine may be used, and examples thereof include: aliphatic diamines, aromatic diamines, diaminoorganosiloxanes, and the like. The aliphatic diamine includes a chain diamine and an alicyclic diamine.

Specific examples of the other diamine include chain diamines: m-xylylenediamine, 1, 3-propylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, 1, 3-bis (aminomethyl) cyclohexane, etc.; examples of alicyclic diamines include: 1, 4-diaminocyclohexane, 4' -methylenebis (cyclohexylamine), and the like;

Examples of the aromatic diamine include: dodecyloxydiaminobenzene, tetradecyloxydiaminobenzene, pentadecyloxydiaminobenzene, hexadecyloxydiaminobenzene, octadecyloxyphenyl, cholesteryloxydiphenyl, cholesteryl oxydiaminophenyl cholestanoyl diaminobenzoate, lanostanyl diaminobenzoate, 3, 6-bis (4-aminobenzoyloxy) cholestane, 3, 6-bis (4-aminophenoxy) cholestane an oriented group-containing diamine such as 1, 1-bis (4- ((aminophenyl) methyl) phenyl) -4-butylcyclohexane, 1-bis (4- ((aminophenyl) methyl) phenyl) -4-heptylcyclohexane, 1-bis (4- ((aminophenoxy) methyl) phenyl) -4-heptylcyclohexane, 1-bis (4- ((aminophenyl) methyl) phenyl) -4- (4-heptylcyclohexyl) cyclohexane, N- (2, 4-diaminophenyl) -4- (4-heptylcyclohexyl) benzamide, and a compound represented by the following formula (E-1);

[ chemical 19]

( In the formula (E-1), X ^I and X ^II are each independently a single bond, -O-, -COO-, or-OCO- (wherein, "" means a bond with the diaminophenyl side); r ^I is alkanediyl having 1 to 3 carbon atoms; r ^II is a single bond or an alkanediyl group having 1 to 3 carbon atoms; r ^III is alkyl, alkoxy, fluoroalkyl or fluoroalkoxy having 1 to 20 carbon atoms; a is 0 or 1; b is an integer of 0 to 3; c is an integer of 0 to 2; d is 0 or 1; wherein, a+b+c is more than or equal to 1 and less than or equal to 3 )

P-phenylenediamine, 4' -diaminodiphenylmethane, 4' -diaminodiphenylamine, 4' -diaminodiphenyl sulfide, 4-aminophenyl-4 ' -aminobenzoate, 4' -diaminoazobenzene, 1, 2-bis (4-aminophenoxy) ethane, 1, 3-bis (4-aminophenoxy) propane, 1, 5-bis (4-aminophenoxy) pentane, 1, 6-bis (4-aminophenoxy) hexane, 1, 7-bis (4-aminophenoxy) heptane, bis [2- (4-aminophenyl) ethyl ] adipic acid, N, N-bis (4-aminophenyl) methylamine, 4' - (2, 2' -oxybis (ethane-2, 1-diyl) bis (oxy)) diphenylamine, 1, 5-diaminonaphthalene, 2' -dimethyl-4, 4' -diaminobiphenyl, 2' -bis (trifluoromethyl) -4,4' -diaminobiphenyl 4,4' -diaminodiphenyl ether, 2-bis [4- (4-aminophenoxy) phenyl ] propane, 2-bis [4- (4-aminophenoxy) phenyl ] hexafluoropropane, 2-bis (4-aminophenyl) hexafluoropropane, 4' - (p-phenylene diisopropylidene) diphenylamine, 1, 4-bis (4-aminophenoxy) benzene, 4' -bis (4-aminophenoxy) biphenyl, N ' -bis (4-aminophenyl) -benzidine, N ' -bis (4-aminophenyl) -N, N ' -dimethylbenzidine, 3, 5-diaminobenzoic acid, 1- (4-aminophenoxy) -2- (4- (4 ' -aminophenyl) phenoxy) ethane, and the like;

Examples of the diaminoorganosiloxane include 1, 3-bis (3-aminopropyl) -tetramethyldisiloxane, and diamines described in JP-A2010-97188 may be used in addition to these.

As the divalent group represented by "-X ^I-(R^I-X^II)_d -" in the formula (E-1), preferably alkanediyl, O-, COO-or O-C ₂H₄ -O- (wherein the bond with "×" is bonded to a diaminophenyl group) having 1 to 3 carbon atoms. The group represented by R ^III is preferably linear. The two amino groups in the diaminophenyl group are preferably located in the 2, 4-position or the 3, 5-position relative to the other groups.

Specific examples of the compound represented by the above formula (E-1) include compounds represented by the following formulae (E-1-1) to (E-1-4).

[ Chemical 20]

When the first specific diamine is used in the synthesis of the polyamic acid (P1), the ratio of the first specific diamine to the total amount of the diamine compounds used in the synthesis of the polyamic acid (P1) is preferably 1 mol% or more, more preferably 2 mol% or more, and still more preferably 5 mol% or more. When the ratio of the first specific diamine is set to the above range, a liquid crystal alignment film excellent in balance of impurity resistance, mechanical strength and permeability can be produced, which is preferable. In addition, from the viewpoint of obtaining a liquid crystal alignment film having more excellent impurity resistance and from the viewpoint of solubility of a polymer by using the second specific diamine, the ratio of the first specific diamine used is preferably 50 mol% or less, more preferably 40 mol% or less, relative to the total amount of diamine compounds used in the synthesis of the polyamic acid (P1).

When the second specific diamine is used in the synthesis of the polyamic acid (P1), the proportion of the second specific diamine used is preferably 1 mol% or more, more preferably 2 mol% or more, and still more preferably 5 mol% or more, based on the total amount of the diamine compounds used in the synthesis of the polyamic acid (P1). When the ratio of the second specific diamine is set to the above range, a liquid crystal alignment film excellent in impurity resistance can be obtained, which is preferable. The proportion of the second specific diamine used is preferably 90 mol% or less, more preferably 85 mol% or less, based on the total amount of the diamine compounds used in the synthesis of the polyamic acid (P1).

Synthesis of Polyamic acid

The polyamic acid (P1) can be obtained by reacting the tetracarboxylic dianhydride described above with a diamine compound and, if necessary, a molecular weight modifier. The ratio of the tetracarboxylic dianhydride to the diamine compound to be used in the synthesis reaction of the polyamic acid (P1) is preferably a ratio of 0.2 to 2 equivalents of the acid anhydride group of the tetracarboxylic dianhydride to 1 equivalent of the amino group of the diamine compound, and more preferably a ratio of 0.3 to 1.2 equivalents of the acid anhydride group of the tetracarboxylic dianhydride to 1 equivalent of the amino group of the diamine compound.

Examples of the molecular weight regulator include: acid monoanhydrides such as maleic anhydride, phthalic anhydride, and itaconic anhydride; monoamine compounds such as aniline, cyclohexylamine and n-butylamine; and monoisocyanate compounds such as phenyl isocyanate and naphthyl isocyanate. The molecular weight regulator is preferably used in a proportion of 20 parts by mass or less, more preferably 10 parts by mass or less, based on 100 parts by mass of the total of the tetracarboxylic dianhydride and the diamine compound used.

The synthesis reaction of the polyamic acid (P1) is preferably carried out in an organic solvent. The reaction temperature in this case is preferably-20℃to 150℃and more preferably 0℃to 100 ℃. The reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours.

Examples of the organic solvent used in the reaction include: aprotic polar solvents, phenolic solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, and the like. Among these organic solvents, one or more selected from the group consisting of aprotic polar solvents and phenolic solvents (organic solvents of the first group) or a mixture of one or more selected from the group consisting of alcohols, ketones, esters, ethers, halogenated hydrocarbons and hydrocarbons (organic solvents of the second group) is preferably used. In the latter case, the ratio of the organic solvent of the second group to the total amount of the organic solvents of the first group and the second group is preferably 50% by mass or less, more preferably 40% by mass or less, and still more preferably 30% by mass or less.

Particularly preferred organic solvents are preferably selected from the group consisting of N-methyl-2-pyrrolidone, N-dimethylacetamide, N-dimethylformamide, dimethylsulfoxide, γ -butyrolactone, tetramethylurea, hexamethylphosphoric triamide, m-cresol, xylenol and halogenated phenols, or mixtures of one or more of them with other organic solvents in the above-mentioned ratio range. The amount (x) of the organic solvent is preferably such that the total amount (y) of the tetracarboxylic dianhydride and the diamine compound is 0.1 to 50% by mass based on the total amount (x+y) of the reaction solution.

In this manner, a reaction solution in which the polyamic acid (P1) was dissolved was obtained. The reaction solution may be directly used for the preparation of a liquid crystal aligning agent, or the polyamic acid (P1) contained in the reaction solution may be separated and then used for the preparation of a liquid crystal aligning agent, or the separated polyamic acid (P1) may be purified and then used for the preparation of a liquid crystal aligning agent. In the case of producing polyimide by dehydrating and ring-closing the polyamic acid (P1), the reaction solution may be directly subjected to the dehydrating and ring-closing reaction, the polyamic acid (P1) contained in the reaction solution may be separated and then subjected to the dehydrating and ring-closing reaction, or the separated polyamic acid (P1) may be purified and then subjected to the dehydrating and ring-closing reaction. The isolation and purification of the polyamic acid (P1) can be carried out according to a conventional method.

(Polyamic acid ester)

The polyamic acid ester as the polymer (P1) can be obtained, for example, by the following method or the like: a method of reacting the polyamic acid (P1) obtained by the synthesis reaction with an esterifying agent; (II) a method of reacting a tetracarboxylic acid diester with a diamine compound; a process for reacting a tetracarboxylic acid diester dihalide with a diamine compound.

In the present specification, the term "tetracarboxylic diester" refers to a compound in which two of four carboxyl groups included in a tetracarboxylic acid are esterified and the remaining two carboxyl groups are carboxyl groups. The term "tetracarboxylic acid diester dihalide" refers to a compound in which two of four carboxyl groups of a tetracarboxylic acid are esterified and the remaining two are halogenated.

As the esterifying agent used in the process [ I ], there may be mentioned: hydroxyl group-containing compounds, acetal-based compounds, halides, epoxy group-containing compounds, and the like. Specific examples thereof include hydroxyl group-containing compounds: alcohols such as methanol, ethanol, and propanol, phenols such as phenol and cresol; examples of the acetal compound include: n, N-dimethylformamide diethyl acetal, N, N-diethylformamide diethyl acetal and the like; the halides may be exemplified by: bromomethane, bromoethane, bromooctadecane, chloromethane, chlorooctadecane, 1-trifluoro-2-iodoethane, etc.; the epoxy group-containing compounds can be exemplified by: propylene oxide, and the like.

The tetracarboxylic diester used in the process [ II ] can be obtained, for example, by: the tetracarboxylic dianhydride exemplified in the description of the synthesis of the polyamic acid (P1) is ring-opened using an alcohol such as methanol or ethanol. The tetracarboxylic acid derivative used in the process [ II ] may be only a tetracarboxylic acid diester, but a tetracarboxylic acid dianhydride may also be used in combination.

The reaction of the process [ III ] is preferably carried out in an organic solvent in the presence of a suitable dehydration catalyst. The organic solvent includes an organic solvent used for the synthesis of the polyamic acid (P1). Examples of the dehydration catalyst include: 4- (4, 6-dimethoxy-1, 3, 5-triazin-2-yl) -4-methylmorpholinium halide, carbonyl imidazole, phosphorus condensing agent, and the like. The reaction temperature in this case is preferably-20℃to 150℃and more preferably 0℃to 100 ℃. The reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours.

The tetracarboxylic acid diester dihalide used in the process [ III ] can be obtained, for example, by: the tetracarboxylic diester obtained in the above manner is reacted with an appropriate chlorinating agent such as thionyl chloride. The tetracarboxylic acid derivative used in the process [ III ] may be only a tetracarboxylic acid diester dihalide, but a tetracarboxylic acid dianhydride may also be used in combination.

The reaction of the process [ III ] is preferably carried out in an organic solvent in the presence of an appropriate base. The organic solvent includes an organic solvent used for the synthesis of the polyamic acid (P1). As the base, for example, tertiary amines such as pyridine, triethylamine and the like can be preferably used; sodium hydride, potassium hydride, sodium hydroxide, potassium hydroxide, sodium, potassium and other alkali metals. The reaction temperature in this case is preferably-20℃to 150℃and more preferably 0℃to 100 ℃. The reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours.

The polyamic acid ester contained in the liquid crystal aligning agent may have only an amic acid ester structure, or may be a partially esterified product in which the amic acid structure and the amic acid ester structure coexist. In addition, the reaction solution obtained by dissolving the polyamic acid ester may be directly used for the preparation of a liquid crystal aligning agent, the polyamic acid ester contained in the reaction solution may be separated and then used for the preparation of a liquid crystal aligning agent, or the separated polyamic acid ester may be purified and then used for the preparation of a liquid crystal aligning agent. The isolation and purification of the polyamic acid ester can be performed according to a conventional method.

(Polyimide)

The polyimide as the polymer (P1) can be obtained, for example, by dehydrating and ring-closing the polyamide acid (P1) synthesized in the above manner and imidizing the same.

The polyimide may be a full imide compound obtained by dehydrating and ring-closing all the amic acid structures of the polyamic acid which is a precursor thereof, or may be a partial imide compound obtained by dehydrating and ring-closing only a part of the amic acid structures and allowing the amic acid structures to coexist with the imide ring structures. The imidization ratio of the polyimide used in the reaction is preferably 20% or more, more preferably 30% to 99%. The imidization ratio is a ratio of the number of imide ring structures to the total of the number of amic acid structures and the number of imide ring structures of the polyimide expressed as a percentage. Here, a part of the imide ring may be an isonimide ring.

The dehydration ring closure of the polyamic acid is preferably performed by a method of heating the polyamic acid, or a method of dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydration ring closure catalyst to the solution, and optionally heating.

In the method of adding the dehydrating agent and the dehydration ring-closing catalyst to the solution of the polyamic acid, for example, an acid anhydride such as acetic anhydride, propionic anhydride, or trifluoroacetic anhydride can be used as the dehydrating agent. The amount of the dehydrating agent to be used is preferably 0.01 to 20 moles based on 1 mole of the amic acid structure of the polyamic acid. As the dehydration ring-closing catalyst, for example, tertiary amines such as pyridine, collidine, lutidine, triethylamine, 1-methylpiperidine and the like can be used. The amount of the dehydration ring-closing catalyst to be used is preferably 0.01 to 10 moles based on 1 mole of the dehydrating agent to be used. Examples of the organic solvent used in the dehydration ring-closure reaction include organic solvents used in the synthesis of polyamic acid. The reaction temperature of the dehydration ring-closure reaction is preferably from 0℃to 180℃and more preferably from 10℃to 150 ℃. The reaction time is preferably 1.0 to 120 hours, more preferably 2.0 to 30 hours.

A reaction solution containing polyimide was obtained in the manner described. The reaction solution can be directly used for preparing the liquid crystal aligning agent, can be used for preparing the liquid crystal aligning agent after removing the dehydrating agent and the dehydration ring-closure catalyst from the reaction solution, can be used for preparing the liquid crystal aligning agent after separating polyimide, or can be used for preparing the liquid crystal aligning agent after refining the separated polyimide. These refining operations may be performed according to existing methods. In addition to this, polyimide can also be obtained by imidization of polyamic acid esters.

The polyamic acid, polyamic acid ester, and polyimide as the polymer (P1) obtained in the above-described manner preferably have a solution viscosity of 20mpa·s to 1,800mpa·s, more preferably 50mpa·s to 1,500mpa·s, when they are prepared into a solution having a concentration of 15 mass%. The solution viscosity (mpa·s) of the polymer is a value obtained by measuring a polymer solution having a concentration of 15 mass% prepared using a good solvent (for example, γ -butyrolactone, N-methyl-2-pyrrolidone, etc.) of the polymer at 25 ℃ using an E-type rotational viscometer.

The weight average molecular weight (Mw) of the polyamic acid, polyamic acid ester, and polyimide of the polymer (P1) in terms of polystyrene as measured by gel permeation chromatography (Gel Permeation Chromatography, GPC) is preferably 1,000 ～ 500,000, more preferably 2,000 ～ 300,000. The molecular weight distribution (Mw/Mn) expressed by the ratio of the Mw to the number average molecular weight (Mn) in terms of polystyrene measured by GPC is preferably 8 or less, more preferably 7 or less, for the polyamide acid, the polyamide acid ester, and the polyimide as the polymer (P1). When the Mw and Mw/Mn of the polyamic acid, polyamic acid ester, and polyimide as the polymer (P1) are in the above-described ranges, good liquid crystal alignment properties of the liquid crystal element can be ensured.

The content of the polymer (P1) in the first liquid crystal aligning agent is preferably 40 mass% or more, more preferably 50 mass% or more, and still more preferably 60 mass% or more, based on the total amount of solid components contained in the liquid crystal aligning agent (i.e., the total mass of components of the liquid crystal aligning agent excluding the solvent).

< Other ingredients >

The first liquid crystal aligning agent may further contain a component other than the polymer (P1) (hereinafter, also referred to as "other component"). As other components, there may be mentioned: a polymer (hereinafter, also referred to as "polymer (Q)") different from the polymer (P1), a crosslinking agent, a solvent, and the like.

Polymer (Q)

The polymer (Q) is a polymer having neither the partial structure (a 1) nor the partial structure (a 2). The main skeleton of the polymer (Q) is not particularly limited. Examples of the polymer (Q) include: polyamic acid, polyamic acid ester, polyimide, polyorganosiloxane, polyester, polyalkene amine, polyurea, polyamide, polyamideimide, polybenzoxazole precursor, polybenzoxazole, cellulose derivative, polyacetal, addition polymer, and the like. When the polymer (P1) is used in combination, the polymer (Q) is preferably at least one selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, polyorganosiloxane and addition polymer, in terms of exhibiting good liquid crystal alignment.

When the polymer (Q) is contained in the liquid crystal aligning agent, the content of the polymer (Q) is preferably 1 mass% or more, more preferably 2 mass% or more, and still more preferably 5 mass% or more, based on the total amount of the polymer (P1) and the polymer (Q). The content of the polymer (Q) is preferably 95 mass% or less, more preferably 80 mass% or less, based on the total amount of the polymer (P1) and the polymer (Q).

Crosslinking agent

The first liquid crystal aligning agent preferably contains, as a crosslinking agent component, a compound (hereinafter also referred to as "compound (a)") having at least one group (hereinafter also referred to as "crosslinkable group F1") selected from the group consisting of a group represented by-OE ¹ in which E ¹ is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, OR a monovalent releasing group, a mercapto group, a protected mercapto group, an amino group, a protected amino group, an oxetanyl group, and an oxetanyl group, -Si (OR ¹¹)_r(R¹²)_3-r) in which R ¹¹ and R ¹² are monovalent hydrocarbon groups having 1 to 10 carbon atoms independently of each other, R is an integer of 1 to 3, R is an integer of 2 OR 3, R ¹¹ is the same OR different, R is 1, R ¹² is the same OR different, and a polymerizable carbon-carbon double bond group.

Among the groups represented by-OE ¹, the monovalent releasable group represented by E ¹ is preferably a group which is released by heat or light and which replaces a hydrogen atom. Specific examples of the releasable group represented by E ¹ include: an ether-based dissociable group such as an alkyl group having 7 or less carbon atoms, a benzyl group, or a p-methoxybenzyl group; an acetal-based releasable group such as a methoxymethyl group, an ethoxyethyl group, or a 2-tetrahydropyranyl group; acyl group-releasing groups such as acetyl and benzoyl; allyl group-dissociable groups such as allyl group and methallyl group; silyl ether-based releasing groups such as trimethylsilyl, triethylsilyl, and t-butyldimethylsilyl. Among these, the releasable group represented by E ¹ is preferably an ether releasable group, an acetal releasable group or an acetyl group, more preferably an alkyl group having 4 to 7 carbon atoms, a 2-tetrahydropyranyl group, a methoxymethyl group, a 1-ethoxyethyl group or an acetyl group, and even more preferably a 2-tetrahydropyranyl group, a methoxymethyl group, a 1-ethoxyethyl group or an acetyl group, from the viewpoint of achieving both ease of release and storage stability.

Among them, E ¹ is particularly preferably a hydrogen atom, an alkyl group having 7 or less carbon atoms, an acetyl group, a 2-tetrahydropyranyl group, a methoxymethyl group or a 1-ethoxyethyl group, from the viewpoint of improving sealing adhesion. In addition, in terms of high reactivity with the polymer (P1) (particularly, the fluorene ring site in the partial structure (a 1)), the group represented by-OE ¹ is preferably a group bonded to a carbon atom, more preferably an alkanediyl group, and further preferably a group constituting a part of a hydroxymethyl group or a hydroxyalkylamide group.

The releasable group bonded to the nitrogen atom in the protected amino group may be the same as the specific example and preferred example of the case where Y ¹ in the above formula (2) is a thermally releasable group. In addition, among the protected mercapto groups, the same groups as exemplified as E ¹ are exemplified as the releasable groups bonded to sulfur atoms.

When the crosslinkable group F1 of the compound (a) is an amino group or a protected amino group, the compound (a) is preferably a chain compound. In the case where the compound (a) has a primary amino group-protected group as a protected amino group, the protected amino group may be a group in which only one of 2 hydrogen atoms in the primary amino group is substituted with a releasable group, or may be a group in which all 2 hydrogen atoms are substituted with a releasable group. That is, in the case where at least one of 2 hydrogen atoms in the primary amino group is substituted with a releasable group, the group corresponds to "protected primary amino group".

As the group represented by-Si (OR ¹¹)_r(R¹²)_3-r), examples of the monovalent hydrocarbon group having 1 to 10 carbon atoms represented by R ¹¹ OR R ¹² include monovalent chain hydrocarbon groups having 1 to 10 carbon atoms, monovalent alicyclic hydrocarbon groups having 3 to 10 carbon atoms and monovalent aromatic hydrocarbon groups having 6 to 10 carbon atoms, R ¹¹ is preferably an alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, still more preferably a methyl group OR an ethyl group, R ¹² is preferably an alkyl group having 1 to 10 carbon atoms, OR a substituted OR unsubstituted phenyl group, and more preferably a methyl group, an ethyl group OR a phenyl group, from the standpoint of photoreactivity.

From the viewpoint of improving the crosslinking reactivity, r is preferably 2 or 3, more preferably 3.

When the compound (a) has a polymerizable carbon-carbon double bond group, the polymerizable carbon-carbon double bond group is preferably a part of a group represented by any one of the following formulas (g 1-1) to (g 1-10) in terms of high crosslinking reactivity and obtaining a liquid crystal alignment film excellent in electric characteristics and sealing adhesion.

[ Chemical 21]

(In the formulae (g 1-1) to (g 1-10), "x" represents a bond

When the compound (a) has a polymerizable carbon-carbon double bond group, the compound (a) is preferably a group represented by any one of the above formulas (g 1-1) to (g 1-7), and more preferably a group represented by any one of the above formulas (g 1-1) to (g 1-4) in terms of high crosslinking reactivity and ease of introduction of a functional group.

The amount of crosslinkable group F1 of the compound (a) is not particularly limited. In order to improve the crosslinking reactivity of the polymer (P1) with the compound (a) and obtain a liquid crystal alignment film having a higher film density, the number of crosslinkable groups in one molecule of the compound (a) is preferably 2 or more, more preferably 2 to 10. The compound (a) is preferably a compound (i.e., a low-molecular compound) different from the polymer. The molecular weight of the compound (a) is, for example, 1,200 or less, preferably 1,000 or less, and more preferably 800 or less.

Specific examples of the compound (A) include compounds having a group represented by-OE ¹, compounds represented by the following formulas (5A-1) to (5A-36), and the like;

examples of the compound having a mercapto group or a protected mercapto group include compounds represented by the following formulae (5B-1) to (5B-6);

examples of the compound having an amino group or a protected amino group include compounds represented by the following formulae (5C-1) to (5C-13);

Examples of the compounds having an oxetanyl group or an oxetanyl group include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, triglycidyl triisocyanate, 1, 6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, 2-dibromoneopentyl glycol diglycidyl ether, N, N, N ', N ' -tetraglycidyl-m-xylylenediamine, 1, 3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ', N ' -tetraglycidyl-4, 4' -diaminodiphenylmethane, N, hydrogen peroxide-based epoxidation reaction products of N-diglycidyl-benzylamine, N-diglycidyl-aminomethylcyclohexane, N-diglycidyl-cyclohexylamine, pentaerythritol tetraallyl ether, and the like;

Examples of the compound having a group represented by-Si (OR ¹¹)_r(R¹²)_3-r) include 3-glycidoxypropyl trimethoxysilane, 3-glycidoxypropyl triethoxysilane, 3-glycidoxypropyl methyldimethoxysilane, 2- (3, 4-epoxycyclohexyl) ethyltriethoxysilane, 3- (meth) acryloxypropyl trimethoxysilane, 3- (meth) acryloxypropyl methyldimethoxysilane, 3- (meth) acryloxypropyl methyldiethoxysilane, and vinyltriethoxysilane;

Examples of the compound having a polymerizable carbon-carbon double bond group include ethylene glycol di (meth) acrylate, 1, 6-hexanediol di (meth) acrylate, pentaerythritol tri (meth) acrylate, and compounds represented by the following formulae (5D-1) to (5D-7).

[ Chemical 22]

[ Chemical 23]

[ Chemical 24]

[ Chemical 25]

[ Chemical 26]

[ Chemical 27]

In view of the crosslinking reactivity with the polymer (P1), the compound (a) is preferably at least one selected from the group consisting of a compound having a group represented by-OE 1, a compound having a mercapto group or a protected mercapto group, a compound having an amino group or a protected amino group, and a compound having a polymerizable carbon-carbon double bond group, and more preferably at least one selected from the group consisting of a compound having a group represented by-OE 1, a compound having an amino group, and a compound having a protected amino group.

When the first liquid crystal aligning agent is made to contain the compound (a), the content ratio of the compound (a) is preferably 0.5 parts by mass or more with respect to 100 parts by mass of the total amount of the polymer components contained in the liquid crystal aligning agent (i.e., the total amount of the polymer (P1) and the polymer (Q)) in terms of improving the film density of the liquid crystal aligning film. The content ratio of the compound (a) is more preferably 1 part by mass or more, and still more preferably 5 parts by mass or more, relative to 100 parts by mass of the total amount of the polymer components. In addition, from the viewpoint of obtaining a liquid crystal element having good liquid crystal alignment properties and electric characteristics, and from the viewpoint of improving storage stability of the liquid crystal alignment agent, the content of the compound (a) is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, relative to 100 parts by mass of the total amount of the polymer components.

The first liquid crystal aligning agent may contain a crosslinking agent different from the compound (a). Further, examples of the components other than the solvent to be blended in the first liquid crystal aligning agent include, in addition to the above components: antioxidants, metal chelate compounds, hardening accelerators, surfactants, fillers, dispersants, photosensitizers, acid generators, base generators, radical generators, and the like. The blending ratio thereof may be appropriately selected depending on the respective compounds within a range not impairing the effects of the present disclosure.

Solvent(s)

The first liquid crystal aligning agent is prepared in the form of a liquid composition in which the polymer (P1) and optional components are preferably dispersed or dissolved in a suitable solvent.

Examples of the organic solvent used include: n-methyl-2-pyrrolidone, γ -butyrolactone, γ -butyrolactam, N-dimethylformamide, N-dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol N-propyl ether, ethylene glycol isopropyl ether, ethylene glycol N-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diisobutyl ketone, isopentyl propionate, isopentyl isobutyrate, diisoamyl ether, ethylene carbonate, propylene carbonate, and the like. These may be used singly or in combination of two or more.

The solid content concentration in the liquid crystal aligning agent (the ratio of the total mass of the components of the liquid crystal aligning agent excluding the solvent to the total mass of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility, and the like, and is preferably in the range of 1 to 10 mass%. That is, the liquid crystal alignment agent is applied to the surface of the substrate as described later, and preferably heated, thereby forming a coating film as a liquid crystal alignment film or a coating film as a liquid crystal alignment film. In this case, when the solid content concentration is 1 mass% or more, the film thickness of the coating film can be sufficiently ensured, and a good liquid crystal alignment film tends to be easily obtained. When the solid content is 10 mass% or less, the film thickness of the coating film does not become excessively large, and the viscosity of the liquid crystal aligning agent can be suppressed from increasing, so that the coatability tends to be good.

The range of the solid content concentration particularly preferable differs depending on the use of the liquid crystal aligning agent or the method used when the liquid crystal aligning agent is coated on the substrate. For example, in the case of applying the liquid crystal aligning agent for a liquid crystal display element to a substrate by a rotator method, the solid content concentration (the ratio of the total mass of all components except the solvent in the liquid crystal aligning agent to the total mass of the liquid crystal aligning agent) is particularly preferably in the range of 1.5 to 4.5 mass%. When the printing method is used, it is particularly preferable that the solution viscosity is set to a range of 12 to 50mpa·s by setting the solid content concentration to a range of 3 to 9 mass%. In the case of using the inkjet method, it is particularly preferable to set the solid content concentration to a range of 1 to 5 mass%, and thereby set the solution viscosity to a range of 3 to 15mpa·s. The temperature at which the liquid crystal aligning agent is prepared is preferably 10℃to 50℃and more preferably 20℃to 30 ℃. In addition, in terms of the liquid crystal aligning agent for the retardation film, the solid content concentration of the liquid crystal aligning agent is preferably in the range of 0.2 to 10 mass%, more preferably in the range of 3 to 10 mass%, from the viewpoint of ensuring proper coatability of the liquid crystal aligning agent and the film thickness of the formed coating film.

[ Second liquid Crystal alignment agent ]

Next, the second liquid crystal aligning agent will be described. Note that, the second liquid crystal aligning agent has the same structure as the first liquid crystal aligning agent, and a description thereof will be omitted. The second liquid crystal aligning agent contains a polymer (P2) and a compound (A1).

< Polymer (P2) >

The polymer (P2) is a polymer having a partial structure (a 1) represented by the above formula (1). That is, the polymer (P2) corresponds to the second polymer (P12) that can be contained in the first liquid crystal aligning agent. Specific examples or preferred examples of the partial structure (a 1) of the polymer (P2), the content ratio in the polymer, and other structural units and synthetic methods that the polymer (P2) may have, the description of the polymer (P1) may be cited.

< Compound (A1) >

The compound (A1) is a compound having a total of 2 OR more groups (hereinafter, also referred to as "crosslinkable group F2") selected from the group consisting of-OE ¹ in one molecule (wherein E ¹ is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, OR a monovalent releasing group), a mercapto group, a protected mercapto group, an amino group, a protected amino group, an oxetanyl group, a group represented by-Si (OR ¹¹)_r(R¹²)_3-r), and a polymerizable carbon-carbon double bond group, and specific examples and preferable examples of the group represented by-OE ¹, the protected mercapto group, the protected amino group, the group represented by-Si (OR ¹¹)_r(R¹²)_3-r), and the polymerizable carbon-carbon double bond group include the crosslinkable group F1 of the compound (A).

The number of crosslinkable groups F2 in the compound (A1) is 2 or more, more preferably 2 to 10, from the viewpoint of improving the crosslinking reactivity of the polymer (P2) with the compound (A1) and obtaining a liquid crystal alignment film having a higher film density. The compound (A1) is preferably a compound (i.e., a low-molecular compound) different from the polymer. The molecular weight of the compound (A1) is, for example, 1,200 or less, preferably 1,000 or less, and more preferably 800 or less.

Specific examples of the compound (A1) include compounds having a corresponding crosslinkable group among the compounds shown as the compound (a) which can be formulated in the first liquid crystal aligning agent.

In view of the crosslinking reactivity with the polymer (P2), in the above, the compound (A1) is preferably at least one selected from the group consisting of a compound having a group represented by-OE ¹, a compound having an amino group or a protected amino group, and a compound having a polymerizable carbon-carbon double bond group, and more preferably at least one selected from the group consisting of a compound having a group represented by-OE ¹, a compound having an amino group, and a compound having a protected amino group.

In terms of improving the film density of the liquid crystal alignment film, the content ratio of the compound (A1) in the second liquid crystal alignment agent is preferably 0.5 parts by mass or more with respect to 100 parts by mass of the total amount of the polymer components contained in the liquid crystal alignment agent (i.e., the total amount of the polymer (P2) and the optionally blended polymer (Q)). The content ratio of the compound (A1) is more preferably 1 part by mass or more, and still more preferably 5 parts by mass or more, relative to 100 parts by mass of the total amount of the polymer components. In addition, from the viewpoint of obtaining a liquid crystal element having good liquid crystal alignment properties and electric characteristics, and from the viewpoint of improving storage stability of the liquid crystal alignment agent, the content ratio of the compound (A1) is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, relative to 100 parts by mass of the total amount of the polymer components.

The second liquid crystal aligning agent may further contain a component different from the polymer (P2) and the compound (A1). The other components that can be blended in the second liquid crystal aligning agent include the same components as those exemplified as the other components in the description of the first liquid crystal aligning agent. In addition, regarding the preparation method, viscosity, and the like of the second liquid crystal aligning agent, description of the first liquid crystal aligning agent can be cited.

Liquid crystal alignment film and liquid crystal element

The liquid crystal alignment film of the present disclosure may be formed of the liquid crystal alignment agent prepared in the manner described. The liquid crystal element of the present disclosure includes a liquid crystal alignment film formed using the liquid crystal alignment agent described in the above description. The operation mode of the liquid crystal In the liquid crystal element is not particularly limited, and the liquid crystal element can be applied to various modes such as a twisted nematic (TWISTED NEMATIC, TN) mode, a Super twisted nematic (Super TWISTED NEMATIC, STN) mode, a vertical alignment (VERTICAL ALIGNMENT, VA) mode (including a vertical alignment-Multi-domain vertical alignment (VERTICAL ALIGNMENT-Multi-domain VERTICAL ALIGNMENT, VA-MVA) mode, a vertical alignment-pattern vertical alignment (VERTICAL ALIGNMENT-PATTERNED VERTICAL ALIGNMENT, VA-PVA) mode, etc.), a coplanar switching (In-PLANE SWITCHING, IPS) mode, a fringe field switching (FRINGE FIELD SWITCHING, FFS) mode, an optically compensated bend (Optically Compensated Bend, OCB) mode, and a polymer stable alignment (Polymer Sustained Alignment, PSA) mode. The liquid crystal element can be manufactured by a method including the following steps 1 to 3, for example. In step 1, the substrate is used in a different manner depending on the desired operation mode. The operation modes in step 2 and step 3 are common.

(Step 1: formation of coating film)

First, a liquid crystal alignment agent is applied to a substrate, and the application surface is preferably heated, thereby forming a coating film on the substrate. As the substrate, for example, a transparent substrate containing the following materials can be used: float glass, sodium glass, and the like; plastics such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, and poly (alicyclic olefin). As the transparent conductive film provided on one surface of the substrate, a NESA (NESA) film containing Tin Oxide (SnO ₂) (registered trademark of PPG corporation In the united states), an Indium Tin Oxide (ITO) film containing Indium-Tin Oxide (In ₂O₃-SnO₂), or the like can be used. In the case of manufacturing a TN-type, STN-type, VA-type, or PSA-type liquid crystal element, two substrates provided with a patterned transparent conductive film are used. On the other hand, in the case of manufacturing an IPS type or FFS type liquid crystal element, a substrate provided with an electrode including a transparent conductive film or a metal film patterned into a comb-teeth type and a counter substrate not provided with an electrode are used. As the metal film, for example, a film containing a metal such as chromium can be used. The liquid crystal aligning agent is preferably applied to the substrate on the electrode forming surface by offset printing, spin coating, roll coater or inkjet printing.

After the liquid crystal aligning agent is applied, preheating (prebaking) is preferably performed for the purpose of preventing sagging of the applied liquid crystal aligning agent, and the like. The pre-baking temperature is preferably 30-200 ℃, and the pre-baking time is preferably 0.25-10 minutes. Thereafter, if necessary, a calcination (post baking) step is performed for the purpose of completely removing the solvent or thermally imidizing the amic acid structure present in the polymer. The calcination temperature (post-baking temperature) at this time is preferably 80 to 300℃and the post-baking time is preferably 5 to 200 minutes. The film thickness of the film thus formed is preferably 0.001 μm to 1 μm. After the liquid crystal alignment agent is coated on the substrate, the organic solvent is removed, thereby forming a liquid crystal alignment film or a coating film to be a liquid crystal alignment film.

(Process 2: orientation treatment)

In the case of manufacturing a TN-type, STN-type, IPS-type, or FFS-type liquid crystal device, a process (alignment process) for imparting liquid crystal alignment ability to the coating film formed in step 1 is performed. Thus, the liquid crystal alignment film is obtained by imparting the liquid crystal molecules with alignment ability to the coating film. Examples of the alignment treatment include a rubbing treatment in which a surface of a coating film formed on a substrate is rubbed with cotton (cotton) or the like, and a photo-alignment treatment in which the coating film is irradiated with light to impart liquid crystal alignment ability. On the other hand, in the case of manufacturing a Vertical Alignment (VA) type liquid crystal element, the coating film formed in step 1 may be used as it is as a liquid crystal alignment film, but the alignment treatment may be performed on the coating film. A liquid crystal alignment film preferable for a vertical alignment type liquid crystal element can also be preferably used for a PSA type liquid crystal element.

The light irradiation in the photo-alignment treatment may be performed by the following method or the like: a method of irradiating the coating film after the post-baking step; a method of irradiating the coating film after the pre-baking step and before the post-baking step; a method of irradiating the coating film during heating of the coating film in at least either one of the pre-baking step and the post-baking step. In the photo-alignment treatment, for example, ultraviolet rays and visible rays including light having a wavelength of 150nm to 800nm can be used as radiation for irradiating the coating film. Preferably ultraviolet rays containing light having a wavelength of 200nm to 400 nm. In the case where the radiation is polarized, the radiation may be linearly polarized or partially polarized. In the case where the radiation used is linearly polarized light or partially polarized light, the irradiation may be performed in a direction perpendicular to the substrate surface, in an oblique direction, or in a combination of these directions. When unpolarized radiation is irradiated, the irradiation direction is set to be an oblique direction.

Examples of the light source used include a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, and an excimer laser. The irradiation amount of the radiation is preferably 400J/m ²～20,000J/m², more preferably 1,000J/m ²～5,000J/m². In order to improve the reactivity, the coating film may be irradiated with light while heating the coating film.

In the production of a liquid crystal alignment film, the film subjected to the light irradiation treatment may be heated in a temperature range of 120 ℃ or more and 280 ℃ or less, whereby the liquid crystal alignment property (heat rearrangement) is further improved. The heating may be post baking or a heating treatment performed after post baking independently of post baking. In the case of heat-treating the coating film subjected to the light irradiation treatment, the heating temperature is preferably 140 ℃ or higher, more preferably 150 ℃ to 250 ℃, from the viewpoint of promoting the reorientation of the molecular chains by heating. The heating time is preferably 5 minutes to 200 minutes, more preferably 10 minutes to 60 minutes.

In the case of manufacturing the liquid crystal alignment film, the method may further include the steps of: and contacting the coating film subjected to the light irradiation treatment with water, a water-soluble organic solvent or a mixed solvent of water and a water-soluble organic solvent. Examples of the water-soluble organic solvent include: methanol, ethanol, 1-propanol, isopropanol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclopentanone. Among these, the solvent used in the present step is preferably water, isopropyl alcohol or a mixture thereof. Examples of the method of contacting the coating film with the solvent include, but are not limited to, spraying (spray) treatment, dipping treatment, and liquid-coating treatment. The contact time between the coating film and the solvent is not particularly limited, and is, for example, 5 seconds to 15 minutes. The heat treatment of the coating film may be performed after the contact with the solvent.

(Process 3: construction of liquid Crystal cell)

Two substrates on which liquid crystal alignment films were formed in the above manner were prepared, and liquid crystal was placed between the two substrates placed opposite to each other, thereby manufacturing a liquid crystal cell. In manufacturing a liquid crystal cell, examples include: (1) A method in which two substrates are arranged in a facing manner with a gap (spacer) therebetween so that the liquid crystal alignment films face each other, peripheral portions of the two substrates are bonded together with a sealant, liquid crystal is injected into and filled into a cell gap defined by the substrate surface and the sealant, and then the injection hole is sealed; (2) And a method (one drop filling (ODF)) in which a sealant is applied to a predetermined portion of one of the substrates on which a liquid crystal alignment film is formed, and then liquid crystal is dropped at predetermined portions on the surface of the liquid crystal alignment film, and then the other substrate is bonded so that the liquid crystal alignment film faces the other substrate, and the liquid crystal is spread over the entire surface of the substrate. It is desirable to remove the flow orientation at the time of filling the liquid crystal by heating the liquid crystal cell to a temperature at which the liquid crystal used attains an isotropic phase and then slowly cooling to room temperature.

As the sealant, for example, a hardener, an epoxy resin containing alumina balls as spacers, or the like can be used. As the spacer, a photoresist spacer (photospacer), a bead spacer, or the like can be used. The liquid crystal includes nematic liquid crystal (nematic liquid crystal) and discotic liquid crystal (smectic liquid crystal). Among these, nematic liquid crystals are preferable, and for example, can be used: schiff base (Schiff base) type liquid crystal, azo oxide (azoxy) type liquid crystal, biphenyl type liquid crystal, phenylcyclohexane type liquid crystal, ester type liquid crystal, terphenyl (terphenyl) type liquid crystal, biphenyl cyclohexane type liquid crystal, pyrimidine type liquid crystal, dioxane type liquid crystal, bicyclooctane type liquid crystal, cubane (cubane) type liquid crystal and the like. Further, a cholesteric liquid crystal (cholesteric liquid crystal), a chiral agent, a ferroelectric liquid crystal (ferroelectric liquid crystal), or the like may be added to these liquid crystals.

In the case of manufacturing a PSA-mode liquid crystal element, the following process is performed: after the liquid crystal cell is constructed, the liquid crystal is filled into the cell gap together with the photopolymerizable compound, and then the liquid crystal cell is irradiated with light in a state where a voltage is applied between the conductive films provided on the pair of substrates. That is, the liquid crystal element is preferably manufactured by a method including the following steps.

A step of forming a coating film on each of the conductive films of the pair of substrates having the conductive film using a liquid crystal aligning agent (corresponding to the step 1)

A step of disposing a pair of substrates on which coating films are formed so as to face each other with a liquid crystal layer containing a photopolymerizable compound interposed therebetween to construct a liquid crystal cell (corresponding to the step 3)

Step 3 of irradiating the liquid Crystal cell with light in a state where a voltage is applied between the conductive films

As the photopolymerizable compound, a polyfunctional compound having 2 or more functional groups capable of radical polymerization, such as an acryl group, a (meth) acryl group, a vinyl group, and the like, can be preferably used. Among them, the photopolymerizable compound is preferably a polyfunctional (meth) acrylic compound having 2 or more (meth) acryloyl groups from the viewpoint of reactivity. In addition, from the viewpoint of stably maintaining the alignment of the liquid crystal molecules, it is preferable to use a compound having at least one ring of cyclohexane rings and benzene rings in total as a liquid crystal skeleton as the photopolymerizable compound. As such a photopolymerizable compound, a conventional one can be used. In the production of a PSA-type liquid crystal element, the photopolymerizable compound is used in an amount of, for example, 0.01 to 3 parts by mass, preferably 0.05 to 1 part by mass, based on 100 parts by mass of the total liquid crystal.

The applied voltage may be, for example, 5V to 50V dc or ac. The light to be irradiated may be, for example, ultraviolet light or visible light including light having a wavelength of 150nm to 800nm, and preferably ultraviolet light including light having a wavelength of 300nm to 400 nm. Examples of the light source for irradiating light include a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, and an excimer laser. The irradiation amount of light is preferably 1,000J/m ² or more and 200,000J/m ² or less, more preferably 1,000J/m ²～100,000J/m².

Then, a polarizing plate is attached to the outer surface of the liquid crystal cell as needed. As the polarizing plate, there may be mentioned: a polarizing film called an "H film" in which iodine is absorbed while stretching and orienting polyvinyl alcohol is sandwiched between cellulose acetate protective films, or a polarizing plate including the H film itself. Thus, a liquid crystal element can be obtained.

The liquid crystal element of the present disclosure is effectively applicable to various applications, for example, various display devices such as a timepiece, a portable game machine, a word processor, a notebook Personal computer, a car navigation system, a video camera (cam recorder), a Personal digital assistant (Personal DIGITAL ASSISTANT, PDA), a digital camera, a mobile phone, a smart phone (smart phone), various monitors, a liquid crystal television, an information display, and a light adjusting film. In addition, a liquid crystal element formed using the liquid crystal aligning agent of the present disclosure can also be applied to a phase difference film.

With the present disclosure described above, the following means can be provided.

[ Means 1 ] A liquid crystal aligning agent comprising a polymer (P1), wherein the polymer (P1) has a partial structure (a 1) represented by the formula (1) and a partial structure (a 2) shown below in the same molecule or in different molecules.

Partial structure (a 2): at least one selected from the group consisting of a nitrogen-containing heterocyclic structure, a partial structure represented by the formula (2), and a partial structure represented by the formula (3)

The liquid crystal aligning agent according to [ means 2 ] further comprising a compound (A) having at least one selected from the group consisting of a group represented by-OE ¹ (wherein E ¹ is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms OR a monovalent releasing group), a mercapto group, a protected mercapto group, an amino group, a protected amino group, an oxetanyl group and a Si (group represented by OR ¹¹)_r(R¹²)_3-r) (wherein R ¹¹ and R ¹² are each independently a monovalent hydrocarbon group having 1 to 10 carbon atoms, R is an integer of 1 to 3, and R ¹¹ are the same OR different when R is 2 OR 3, and R ¹² are the same OR different when R is 1) and a polymerizable carbon-carbon double bond group.

The liquid crystal aligning agent according to the above [ means 1] or [ means 2 ], wherein the polymer (P1) has at least one selected from the group consisting of a partial structure represented by the above formula (1-1) and a partial structure represented by the above formula (1-2) as a partial structure comprising the above partial structure (a 1).

The liquid crystal aligning agent according to any one of the above [ means 1] to [ means 3], wherein the polymer (P1) is at least one selected from the group consisting of polyamic acid, polyamic acid ester and polyimide.

The liquid crystal aligning agent according to any one of the above means 1 to 4, wherein the polymer (P1) contains a structural unit derived from at least one selected from the group consisting of a tetracarboxylic acid derivative having the partial structure (a 1) and a diamine having the partial structure (a 1) and a structural unit derived from a diamine having the partial structure (a 2) in the same molecule or in different molecules.

The liquid crystal aligning agent according to any one of [ means 1 ] to [ means 5 ], further comprising a polymer having neither the partial structure (a 1) nor the partial structure (a 2).

[ Means 7 ] A liquid crystal aligning agent comprising a polymer (P2) having a partial structure (a 1) represented by the above formula (1), and at least one compound selected from the group consisting of-OE ¹ having a total of 2 OR more groups in one molecule (wherein E ¹ is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms OR a monovalent releasing group), a mercapto group, a protected mercapto group, an amino group, a protected amino group, an oxetanyl group and-Si (group represented by OR ¹¹)_r(R¹²)_3-r) (wherein R ¹¹ and R ¹² are each independently a monovalent hydrocarbon group having 1 to 10 carbon atoms, R is an integer of 1 to 3, and when R is 2 OR 3, a plurality of R ¹¹ are the same OR different, and when R is 1, a plurality of R ¹² are the same OR different) and a polymerizable carbon-carbon double bond group.

The liquid crystal aligning agent according to the above [ means 8 ], wherein the polymer (P2) has at least one selected from the group consisting of the partial structure represented by the above formula (1-1) and the partial structure represented by the above formula (1-2) as the partial structure including the above partial structure (a 1).

The liquid crystal aligning agent according to the item [ 7 ] or the item [ 8 ], wherein the polymer (P2) is at least one selected from the group consisting of polyamic acid, polyamic acid ester and polyimide.

The liquid crystal aligning agent according to any one of the above means 7 to 9, wherein the polymer (P2) contains a structural unit derived from at least one selected from the group consisting of a tetracarboxylic acid derivative having the above partial structure (a 1) and a diamine having the above partial structure (a 1).

The liquid crystal aligning agent according to any one of the above-mentioned means 7 to means 10, further comprising a polymer having no said partial structure (a 1).

[ Means 12] a liquid crystal alignment film formed using the liquid crystal alignment agent according to any one of [ means 1] to [ means 11 ].

[ Means 13 ] a liquid crystal element comprising the liquid crystal alignment film according to [ means 12 ].

[ Means 14 ] A method for producing a liquid crystal alignment film, comprising: a step of forming a coating film using the liquid crystal aligning agent according to any one of [ means 1] to [ means 11 ]; and a step of applying a liquid crystal aligning ability to the coating film by irradiating the coating film with light.

[ Means 15 ] A method for manufacturing a liquid crystal element, comprising: a step of forming a coating film on each of the conductive films of the pair of substrates having the conductive film by using the liquid crystal aligning agent according to any one of [ means 1] to [ means 11 ]; a step of disposing a pair of substrates on which the coating film is formed, with a liquid crystal layer containing a photopolymerizable compound interposed therebetween, so that the coating film faces each other, thereby constructing a liquid crystal cell; and a step of irradiating the liquid crystal cell with light in a state where a voltage is applied between the conductive films.

Examples (example)

The present invention will be described more specifically with reference to the following examples, but the present invention is not limited to the following examples.

In the following examples, the imidization ratio of polyimide in the polymer solution, and the weight average molecular weight (Mw), number average molecular weight (Mn), and epoxy equivalent of the polymer were measured by the following methods.

[ Imidization Rate of polyimide ]

The polyimide solution was poured into pure water, and the obtained precipitate was dried under reduced pressure at room temperature, and then dissolved in deuterated dimethyl sulfoxide, followed by measurement by hydrogen nuclear magnetic resonance (¹H-Nuclear Magnetic Resonance,¹ H-NMR) at room temperature using tetramethylsilane as a reference substance. The imidization rate [% ] was determined from the obtained ¹ H-NMR spectrum by using the following formula (1).

Imidization ratio [% ] = (1- (a ¹/(A² ×α))) ×100 … (1)

( In the formula (1), A ¹ is the peak area of proton source of NH group occurring around chemical shift 10 ppm; a ² is the peak area of other proton sources; alpha is the number proportion of other protons relative to 1 proton of NH group in the precursor of the polymer (polyamic acid) )

[ Weight average molecular weight (Mw) and number average molecular weight (Mn) of Polymer ]

Mw and Mn were measured by Gel Permeation Chromatography (GPC) under the following conditions. The molecular weight distribution (Mw/Mn) was calculated from the Mw and Mn obtained.

The device comprises: GPC-101 of Showa electrician (Strand) "

GPC column: "GPC-KF-801", "GPC-KF-802", "GPC-KF-803" and "GPC-KF-804" manufactured by Shimadzu GLC (Strand) are combined

Mobile phase: tetrahydrofuran (THF)

Column temperature: 40 DEG C

Flow rate: 1.0 mL/min

Sample concentration: 1.0 mass%

Sample injection amount: 100 mu L

A detector: differential refractometer

Standard substance: monodisperse polystyrene

[ Epoxy equivalent weight ]

Measured by the hydrochloric acid-methyl ethyl ketone method described in Japanese Industrial Standard (Japanese Industrial Standards, JIS) C2105.

The necessary amounts of the raw material compounds and polymers used in the examples below were ensured by repeating the synthesis in the synthesis scheme shown in the synthesis examples below, if necessary. In the examples and comparative examples, "parts" and "%" are mass-based unless otherwise specified.

The abbreviations of the compounds are described below. In the following, the "compound represented by the formula (X)" may be simply referred to as "compound (X)".

(Tetracarboxylic dianhydride)

[ Chemical 28]

[ Chemical 29]

(Diamine compound)

[ Chemical 30]

[ 31]

[ Chemical 32]

(Other Compounds)

[ 33]

[ Chemical 34]

[ 35]

< Synthesis of Polymer >

1. Synthesis of Polyamic acid

Synthesis example 1

10 Parts by mol of the compound (CA-2) and 90 parts by mol of the compound (CA-3) as tetracarboxylic dianhydride, 10 parts by mol of the compound (DA-1) and 20 parts by mol of the compound (DB-2) and 10 parts by mol of the compound (DC-15), 35 parts by mol of the compound (DC-2) and 25 parts by mol of the compound (DC-17) were dissolved in N-methyl-2-pyrrolidone (N-methyl-2-pyrrolidone, NMP) and reacted at 60℃for 6 hours to obtain a solution containing 20% by mass of polyamic acid (which was defined as a polymer (PAA-1)).

Synthesis example 2 to Synthesis example 20

The same operations as in Synthesis example 1 were carried out except that the types and amounts of the tetracarboxylic dianhydride and the diamine compound used were changed as described in Table 1, to obtain polyamic acids (polymers (PAA-2) to (PAA-20)). In table 1, the numerical values of the tetracarboxylic dianhydrides (acid dianhydride 1 to acid dianhydride 3) represent the proportions (molar ratios) of the respective compounds with respect to 100 parts by mole of the total amount of the tetracarboxylic dianhydrides used for the synthesis of the polyamic acid. The numerical values of the diamine compounds (diamine 1 to diamine 6) represent the proportion (molar ratio) of each compound to 100 parts by mole of the total amount of the diamine compounds used in the synthesis of the polyamic acid.

2. Synthesis of polyimide

Synthesis example 21

80 Parts by mol of the compound (CB-3) and 20 parts by mol of the compound (CB-4) which are tetracarboxylic dianhydrides, 20 parts by mol of the compound (DA-1) and 20 parts by mol of the compound (DB-1) and 10 parts by mol of the compound (DC-14), 25 parts by mol of the compound (DC-11) and 25 parts by mol of the compound (DC-18) are dissolved in NMP, and reacted at 60℃for 6 hours to obtain a solution containing 20% by mass of polyamic acid. Then, NMP was added to the polyamic acid solution obtained to prepare a solution having a polyamic acid concentration of 10% by mass, pyridine and acetic anhydride were added thereto, and the solution was subjected to a dehydration ring-closure reaction at 80℃for 4 hours. After the dehydration ring-closure reaction, the solvent in the system was replaced with new NMP to obtain a solution containing polyimide having an imidization ratio of about 69% by mass of 15% (this was referred to as a polymer (PI-1)).

Synthesis examples 22 to 33

The same operations as in Synthesis example 21 were performed except that the types and amounts of the tetracarboxylic dianhydride and the diamine compound to be used were changed as described in Table 1, to obtain polyimides (polymers (PI-2) to (PI-13)). In table 1, the numerical values of the tetracarboxylic dianhydrides (acid dianhydride 1 and acid dianhydride 2) represent the proportions (molar ratios) of the respective compounds with respect to 100 parts by mole of the total amount of the tetracarboxylic dianhydride used for the synthesis of the polyimide. The numerical values of the diamine compounds (diamine 1 to diamine 6) represent the proportion (molar ratio) of each compound to 100 parts by mole of the total amount of the diamine compounds used in the synthesis of the polyimide.

TABLE 1

3. Synthesis of polyorganosiloxanes

Synthesis example 34

A reaction vessel comprising a stirrer, a thermometer, a dropping funnel and a reflux condenser was charged with 100.0g of 2- (3, 4-epoxycyclohexyl) ethyltrimethoxysilane (the compound represented by the formula (S-1)), 500g of methyl isobutyl ketone and 10.0g of triethylamine, and mixed at room temperature. Then, 100g of deionized water was added dropwise from the addition funnel over 30 minutes, followed by stirring under reflux while carrying out the reaction at 80℃for 6 hours. After the completion of the reaction, the organic layer was taken out and washed with a 0.2 mass% ammonium nitrate aqueous solution until the washed water became neutral, and then the solvent and water were distilled off under reduced pressure, whereby an epoxy group-containing polyorganosiloxane (ESSQ-1) was obtained as a viscous transparent liquid. The weight average molecular weight Mw of the obtained polyorganosiloxane (ESSQ-1) was 3,500 and the epoxy equivalent was 180 g/mol.

A200 mL three-necked flask was charged with 10.0g of polyorganosiloxane (ESSQ-1), 30.28g of methyl isobutyl ketone as a solvent, 20 mol% of compound (S-2) as a modifying component (carboxylic acid) based on the total amount of epoxy groups contained in polyorganosiloxane (ESSQ-1), 10 mol% of compound (S-3) based on the total amount of epoxy groups contained in polyorganosiloxane (ESSQ-1), and 0.10g of UCAT X (trade name, manufactured by Sanremo-Apro) as a catalyst, and the mixture was stirred at 100℃for 48 hours to carry out a reaction. After completion of the reaction, ethyl acetate was added to the reaction mixture, the obtained solution was washed three times with water, and after drying the organic layer with magnesium sulfate, the solvent was distilled off, whereby polyorganosiloxane (PSQ-1) having a liquid crystal alignment group was obtained. The weight average molecular weight (Mw) of the polymer obtained was 8000.

4. Synthesis of styrene-maleimide copolymer

Synthesis example 35

18.7 Mmol of compound (MA-2), 18.7 mmol of compound (MA-4), 10.6 mmol of compound (MA-6) and 5.3 mmol of compound (MA-7), 0.98g of 2,2' -azobis (2, 4-dimethylvaleronitrile) as a radical polymerization initiator, and 50mL of N-methyl-2-pyrrolidone (NMP) as a solvent were charged into a 100mL two-necked flask under nitrogen, and polymerized at 70℃for 6 hours. After reprecipitation in methanol, the precipitate was filtered and dried under vacuum at room temperature for 8 hours, whereby an addition polymer (which was designated as polymer (MI-1)) was obtained. The weight average molecular weight (Mw) measured by GPC based polystyrene conversion was 35000 and the molecular weight distribution (Mw/Mn) was 2.

Synthesis example 36

An addition polymer (MI-2)) was obtained in the same manner as in Synthesis example 35, except that the types and amounts of the used polymerization monomers were changed as shown in Table 2.

TABLE 2

< Preparation and evaluation of liquid Crystal alignment agent >

Example 1: PSA type liquid Crystal display element

1. Preparation of liquid Crystal alignment agent

The solution containing the polymer (PAA-1) obtained in synthesis example 1 was diluted with NMP and butyl cellosolve (butyl cellosolve, BC) to prepare a solution having a solvent composition of NMP/bc=80/20 (mass ratio) and a solid content concentration of 3.5 mass%. The solution was filtered using a filter having a pore size of 0.2 μm, thereby preparing a liquid crystal aligning agent (AL-1).

2. Preparation of liquid Crystal composition

To 10g of nematic liquid crystal (MLC-6608 manufactured by Merck) was added 5 mass% of the liquid crystalline compound represented by the following formula (L1-1) and 0.3 mass% of the photopolymerizable compound represented by the following formula (L2-1) and mixed to obtain a liquid crystal composition LC1.

[ 36]

3. Preparation of composition for forming insulating film

A flask including a cooling tube and a stirrer was charged with 7 parts by mass of 2,2' -azobis (2, 4-dimethylvaleronitrile), 200 parts by mass of propylene glycol monomethyl ether acetate, 15 parts by mass of methacrylic acid, 30 parts by mass of glycidyl methacrylate, 20 parts by mass of styrene, 5 parts by mass of 2-hydroxyethyl acrylate, and 30 parts by mass of isobornyl acrylate, and after nitrogen substitution, stirring was slowly started. After the reaction solution was heated to 62 ℃, the temperature was maintained for 5 hours, and a polymer solution containing the acrylic copolymer (R-1) was obtained. The obtained polymer solution was added dropwise to 900 parts by mass of hexane to precipitate an acrylic copolymer (R-1). The acrylic copolymer (R-1) thus precipitated was separated, 150 parts by mass of propylene glycol monomethyl ether acetate was placed therein, heated to 40℃and distilled under reduced pressure to obtain a polymer solution containing the acrylic copolymer (R-1). The solid content concentration of the obtained polymer solution containing the acrylic copolymer (R-1) was 30% by mass, the area of the unreacted monomer and the polymerization initiator as a result of GPC analysis was 2.3%, and the weight average molecular weight (Mw) was 12800.

The insulating film composition was prepared by mixing 25 parts by mass of 4,4' - [1- [4- [1- [ 4-hydroxyphenyl ] -1-methylethyl ] phenyl ] ethylene ] bisphenol (1.0 mol) as a sensitizer with a condensate of 1, 2-naphthoquinone diazide-5-sulfonyl chloride (2.0 mol), 5 parts by mass of a mixture of dipentaerythritol hexaacrylate and dipentaerythritol pentaacrylate (manufactured by KAYARAD) as a polymerizable compound (manufactured by japan chemical company), 10 parts by mass of 2, 4-trimethyl-1, 3-pentanediol monoisobutyrate (manufactured by synergetic kylin (Kyowa Hakko Kirin) as a film-forming aid, "Jiang Wanuo (KYOWANOL) M"), SH28PA (manufactured by dori-corning corporation) as a leveling agent, and dissolving the mixture in a diethylene glycol methyl ether to have a solid content of 18% by mass, and then filtering the mixture with a filter (RD) of 0.2 μm to obtain a film composition (1-filter).

4. Fabrication of substrate including insulating film

The insulating film-forming composition (RD-1) was applied to a glass substrate by a spin coater and then prebaked on a heating plate at 90℃for 2 minutes. Then, the entire surface of the substrate was irradiated with light of 300mJ/cm ² using a proximity type exposure machine (Canon, "MA-1200" (ghi ray mixing)), and then heated (post-baking) at 230℃for 30 minutes in an oven to harden the substrate, thereby forming an insulating film having a film thickness of 3. Mu.m, on the glass substrate.

5. Manufacture of liquid Crystal cell for evaluation of impurity resistance

The liquid crystal alignment agent (AL-1) was applied to the electrode formation surface of the substrate provided with the patterned comb-teeth-shaped ITO electrode and the insulating film formation surface of the substrate including the insulating film, respectively, by a rotator, and pre-baked by a heating plate at 80℃for 1 minute. Thereafter, the substrate was heated at 230℃for 1 hour in an oven in which nitrogen gas was substituted for the inside of the oven to prepare a pair (two sheets) of substrates each having a liquid crystal alignment film with a thickness of 0.1. Mu.m.

The outer periphery of the surface of the substrate including the insulating film, which has the liquid crystal alignment film, was coated with an epoxy resin adhesive containing alumina spheres having a diameter of 3.5 μm by screen printing, and then the liquid crystal alignment film surfaces of the pair of substrates were brought into contact with each other and pressure-bonded, and the adhesive was thermally cured at 150 ℃ for 1 hour. Then, after filling the liquid crystal composition LC1 into the gap between the substrates from the liquid crystal injection port, the liquid crystal injection port is sealed with an epoxy adhesive. Further, in order to remove the flow alignment at the time of liquid crystal injection, the liquid crystal cell was manufactured by heating the liquid crystal cell at 130 ℃ and then gradually cooling the liquid crystal cell to room temperature. Further, since the substrate is easy to manufacture, the liquid crystal cell for evaluating the impurity resistance is manufactured using an electrode substrate for an IPS type liquid crystal cell.

6. Manufacturing of liquid crystal cell for evaluating cell transmittance

The liquid crystal alignment agent (AL-1) prepared in the above was applied onto the transparent electrode surface of a glass substrate having a transparent electrode containing an ITO film using a rotator, prebaked for 1 minute using a heating plate at 80 ℃, and then heated in an oven replaced with nitrogen gas at 230 ℃ for 1 hour to remove the solvent, thereby forming a coating film (liquid crystal alignment film) having a film thickness of 0.1 μm. The coating film was subjected to a rubbing treatment at a roll rotation speed of 400rpm, a stage moving speed of 3 cm/sec, and a Mao Yaru length of 0.1mm by using a rubbing machine having a roll around which a rayon cloth was wound. Thereafter, ultrasonic cleaning was performed in ultrapure water for 1 minute, followed by drying in a clean oven at 100 ℃ for 10 minutes, thereby obtaining a substrate having a liquid crystal alignment film. The operation is repeated to obtain a pair (two sheets) of substrates having liquid crystal alignment films. The rubbing treatment is a weak rubbing treatment for the purpose of controlling collapse of the liquid crystal and performing alignment division by a simple method.

The outer periphery of the surface of one of the substrates having the liquid crystal alignment film was coated with an epoxy resin adhesive containing alumina spheres having a diameter of 3.5 μm by screen printing, and then the liquid crystal alignment film surfaces of the pair of substrates were superimposed on each other and pressure-bonded, and the adhesive was thermally cured by heating at 150℃for 1 hour. Then, after filling the liquid crystal composition LC1 into the gap between the substrates from the liquid crystal injection port, the liquid crystal injection port was sealed with an epoxy adhesive, and further, in order to remove the flow orientation at the time of liquid crystal injection, it was heated at 150 ℃ for 10 minutes and then cooled down to room temperature gradually.

Then, in the obtained liquid crystal cell, ultraviolet rays were irradiated with an irradiation amount of 50,000J/m ² by an ultraviolet irradiation device using a metal halide lamp as a light source in a state where the liquid crystal was driven by applying an alternating current of 10V at a frequency of 60Hz between the electrodes. The irradiation amount is a value measured using a light meter measuring with a wavelength of 365nm as a reference. Thereby, a PSA-type liquid crystal cell was produced.

7. Evaluation

(1) Evaluation of impurity resistance

After the liquid crystal cell produced in the above-mentioned item 5 was allowed to stand in an oven at 60 ℃, a Voltage Holding Ratio (VHR) was measured under conditions of 1V and 1670 milliseconds using a VHR measuring device "VHR-1" manufactured by Toyo Technica Co. When VHR is higher than 60%, it is "good (∈)", when VHR is 60% or lower and 45% or higher, "delta" (is "acceptable), and when VHR is less than 45%, it is" poor (×) ". As a result, the electrical characteristics of the examples were evaluated as "good (∈)".

(2) Evaluation of seal adhesion

The liquid crystal alignment agent (AL-1) was applied onto a glass substrate using a rotator, prebaked for 2 minutes using a heating plate at 80℃and then heated (post-baked) for 30 minutes using an oven at 230℃in which nitrogen gas was substituted for the inside of the oven, whereby a coating film (liquid crystal alignment film) having an average film thickness of 0.10 μm was formed. Two glass substrates having coating films formed thereon were produced by repeating the same operations as described above. An ODF sealant (S-WB 42, manufactured by water chemical Co., ltd.) was applied to the coating film of one glass substrate on which the coating film was formed so that the width was 0.5mm, and the coating film of the other glass substrate was bonded so as to be in contact with the ODF sealant. Thereafter, 30,000J/m ² (converted to 365 nm) of light was irradiated with a metal halide lamp, and then heated in an oven at 120℃for 1 hour. Thereafter, the sealing adhesion was evaluated by measuring the adhesion force using a tensile compression tester (model: SDWS-0201-100 SL) manufactured by the Ministry of China.

In the evaluation, the case where the adhesion force was 180N/cm ² or more was "particularly good (verygood)", the case where 170N/cm ² or more and less than 180N/cm ² was "good (good)", the case where 150N/cm ² or more and less than 170N/cm ² was "delta" and the case where less than 150N/cm ² was "poor (×)". As a result, the sealing adhesion of the example was evaluated as "good (∈)".

(3) Measurement of cell transmittance

For the liquid crystal cell manufactured in the above 6, the absorption spectrum in the ultraviolet-visible light region was measured using an ultraviolet-visible near infrared spectrophotometer (manufactured by Japanese spectroscopic Co., ltd., product name "V-670"). Further, the incident angle to the liquid crystal cell was set to 0 °. The average transmittance at a wavelength of 380nm to 800nm was set to 87% or more as "good (good)", 85% or more and less than 87% as "delta)", and less than 85% as "poor (×)". As a result, the cell transmittance of the example was evaluated as "good (∈)".

Examples 2 to 19 and comparative examples 1 to 5

Liquid crystal aligning agents (AL-2) to (AL-19) and liquid crystal aligning agents (AR-1) to (AR-5) were prepared in the same manner as in example 1, except that the composition of the liquid crystal aligning agent was changed as shown in table 3. Using the obtained liquid crystal aligning agent, a liquid crystal cell was produced in the same manner as in example 1, and various evaluations were performed. The results are shown in Table 3. In table 3, the numerical values in the mass ratio column indicate the blending ratio (parts by mass) of each compound (polymer, additive) in terms of solid content with respect to 100 parts by mass of the total amount of the polymer components used in the preparation of the liquid crystal aligning agent.

Example 20: light FFS type liquid Crystal display element

1. Preparation of liquid Crystal alignment agent, evaluation of impurity resistance and sealing adhesion

A liquid crystal aligning agent (AL-20) was prepared in the same manner as in example 1, except that the composition of the liquid crystal aligning agent was changed as in Table 3. A liquid crystal cell for evaluation of impurity resistance was produced in the same manner as in example 1, except that the obtained liquid crystal aligning agent (AL-20) was used and negative liquid crystal (manufactured by Merck) and MLC-6608 was used as a liquid crystal composition, and the impurity resistance was evaluated, and the sealing adhesion was evaluated using the liquid crystal aligning agent (AL-20). The results are shown in Table 3.

2. Measurement of cell transmittance

The liquid crystal alignment agent (AL-20) prepared in the above was applied onto the transparent electrode surface of a glass substrate having a transparent electrode containing an ITO film using a rotator, prebaked for 1 minute using a heating plate at 80 ℃, and then heated in an oven replaced with nitrogen gas at 200 ℃ for 1 hour to remove the solvent, thereby forming a coating film (liquid crystal alignment film) having a film thickness of 0.1 μm. The operation is repeated to obtain a pair (two sheets) of substrates having liquid crystal alignment films. The obtained coating film was subjected to photo-alignment treatment by irradiating ultraviolet rays 1,000J/m ² containing bright lines of 254nm linearly polarized light from the substrate normal direction using an hg—xe lamp. The irradiation amount is a value measured using a light meter measuring with a wavelength of 245nm as a reference. Then, the coating film subjected to the photo-alignment treatment was heated in a clean oven at 200 ℃ for 30 minutes to perform a heat treatment, thereby forming a liquid crystal alignment film.

The outer periphery of the surface of one of the substrates having the liquid crystal alignment film was coated with an epoxy resin adhesive containing alumina spheres having a diameter of 3.5 μm by screen printing, and then the liquid crystal alignment film surfaces of the pair of substrates were superimposed on each other and pressure-bonded, and the adhesive was thermally cured by heating at 150℃for 1 hour. Then, after negative liquid crystal (MLC-6608, manufactured by Merck) was filled into the gap between the substrates from the liquid crystal injection port, the liquid crystal injection port was sealed with an epoxy adhesive, and further, the liquid crystal was heated at 150 ℃ for 10 minutes and then cooled down to room temperature gradually in order to remove the flow orientation at the time of liquid crystal injection.

The absorption spectrum of the ultraviolet-visible light region of the produced liquid crystal cell was measured using an ultraviolet-visible near-infrared spectrophotometer (manufactured by Japanese spectroscopic Co., ltd., product name "V-670"). The evaluation results are shown in table 3.

Example 21

A liquid crystal aligning agent (AL-21) was prepared in the same manner as in example 1, except that the composition of the liquid crystal aligning agent was changed as in table 3. Further, using the obtained liquid crystal aligning agent (AL-21), various evaluations were performed in the same manner as in example 20. The results are shown in Table 3.

Example 22: friction FFS type liquid Crystal display element

A liquid crystal aligning agent (AL-22) was prepared in the same manner as in example 1, except that the composition of the liquid crystal aligning agent was changed as in table 3. A liquid crystal cell for evaluation of impurity resistance was produced in the same manner as in example 1 except that the obtained liquid crystal aligning agent (AL-22) was used and negative liquid crystal (manufactured by Merck) and MLC-6608 was used as a liquid crystal composition, and the impurity resistance was evaluated, and the seal adhesion was evaluated using the liquid crystal aligning agent (AL-22). The results are shown in Table 3.

2. Measurement of cell transmittance

The liquid crystal alignment agent (AL-22) prepared in the above was applied onto the transparent electrode surface of a glass substrate having a transparent electrode containing an ITO film using a rotator, prebaked for 1 minute using a heating plate at 80 ℃, and then heated in an oven replaced with nitrogen gas at 200 ℃ for 1 hour to remove the solvent, thereby forming a coating film (liquid crystal alignment film) having a film thickness of 0.1 μm. Then, the surface of the coating film was subjected to a rubbing treatment at a roller rotation speed of 1000rpm, a stage moving speed of 3 cm/sec, and a Mao Yaru length of 0.3mm by using a rubbing machine having a roller around which a rayon cloth was wound. Thereafter, ultrasonic cleaning was performed in ultrapure water for 1 minute, followed by drying in a clean oven at 100℃for 10 minutes. The operation is repeated to obtain a pair (two sheets) of substrates having liquid crystal alignment films.

Example 23

A liquid crystal aligning agent (AL-23) was prepared in the same manner as in example 1, except that the composition of the liquid crystal aligning agent was changed as in table 3. Further, using the obtained liquid crystal aligning agent (AL-23), various evaluations were performed in the same manner as in example 22. The results are shown in Table 3.

Example 24: light VA type liquid Crystal display element

A liquid crystal aligning agent (AL-24) was prepared in the same manner as in example 1, except that the composition of the liquid crystal aligning agent was changed as in Table 3. A liquid crystal cell for evaluation of impurity resistance was produced in the same manner as in example 1, except that the obtained liquid crystal aligning agent (AL-24) was used and negative liquid crystal (manufactured by Merck) and MLC-6608 was used as a liquid crystal composition, and the impurity resistance was evaluated, and the sealing adhesion was evaluated using the liquid crystal aligning agent (AL-24). The results are shown in Table 3.

2. Measurement of cell transmittance

The liquid crystal alignment agent (AL-24) prepared in the above was applied onto the transparent electrode surface of a glass substrate having a transparent electrode containing an ITO film using a rotator, prebaked for 1 minute using a heating plate at 80 ℃, and then heated in an oven replaced with nitrogen gas at 200 ℃ for 1 hour to remove the solvent, thereby forming a coating film (liquid crystal alignment film) having a film thickness of 0.1 μm. Then, the surface of the coating film was irradiated with polarized ultraviolet rays 1,000J/m ² including bright lines of 313nm from a direction inclined by 40 ° with respect to the substrate normal using an Hg-Xe lamp and a glan-taylor prism (glan-taylor prism) to impart liquid crystal alignment ability. The operation is repeated to obtain a pair (two sheets) of substrates having liquid crystal alignment films.

Example 25

A liquid crystal aligning agent (AL-25) was prepared in the same manner as in example 1, except that the composition of the liquid crystal aligning agent was changed as in Table 3. Further, using the obtained liquid crystal aligning agent (AL-25), various evaluations were performed in the same manner as in example 24. The results are shown in Table 3.

TABLE 3

As shown in table 3, the impurity resistance, the seal adhesion and the cell transmittance of examples 1 to 25 were evaluated as "particularly good (excellent)", "good (o)", or "acceptable (Δ)", and the balance of various properties was good. Of these, the evaluation of the seal adhesion of examples 1 to 13, 17 to 20, and 22 to 25, in which the compound (a) or the compound (A1) was blended, was "particularly good (excellent) (" excellent ") or" good (o) ", and was particularly excellent.

In contrast, the evaluation of one or more of the impurity resistance, the seal adhesion and the cell transmittance of comparative examples 1 to 5, which is "poor (x)", was inferior to that of examples 1 to 25.

Claims

1. A liquid crystal alignment agent, comprising a polymer (P1), wherein the polymer (P1) has a partial structure (a1) represented by the following formula (1) and a partial structure (a2) shown below in the same molecule or in different molecules;

In formula (1), ^R1 and ^R2 are independently monovalent substituents; n1 and n2 are independently 0 or 1; m1 is an integer from 0 to (n1×2+4); m2 is an integer from 0 to (n2×2+4); when there are multiple ^R1s , the multiple ^R1s are the same or different, and when there are multiple ^R2s , the multiple ^R2s are the same or different; "*" represents a bond to a carbon atom,

Partial structure (a2): at least one selected from the group consisting of a nitrogen-containing heterocyclic structure, a partial structure represented by the following formula (2) and a partial structure represented by the following formula (3)

In formula (2), ^Y1 is a hydrogen atom or a monovalent group that is separated by heating and replaces the hydrogen atom; ^A1 is an alkanediyl group, a substituted or unsubstituted divalent alicyclic group, or a substituted or unsubstituted divalent aromatic ring group; ^A2 is an alkanediyl group; "*" represents a bonding bond,

In formula (3), ^Y2 is a monovalent group that is detached by heating and replaces a hydrogen atom; ^X3 is a single bond or an alkanediyl group; ^R4 and ^R5 are independently a hydrogen atom or a monovalent hydrocarbon group; and "*" represents a bonding bond.

2. The liquid crystal alignment agent according to claim 1, further comprising a compound (A), wherein the compound (A) has at least one selected from the group consisting of a group represented by ^-OE1 , a mercapto group, a protected mercapto group, an amino group, a protected amino group, an oxacyclopropyl group, an oxetanyl group, a group represented by -Si( ^OR11 ) _r ( ^R12 ) _3-r , and a polymerizable carbon-carbon double bond group, wherein ^E1 is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a monovalent leaving group, ^R11 and ^R12 are independently monovalent hydrocarbon groups having 1 to 10 carbon atoms, r is an integer of 1 to 3, and when r is 2 or 3, multiple ^R11s are the same or different, and when r is 1, multiple ^R12s are the same or different.

3. The liquid crystal alignment agent according to claim 1, wherein the polymer (P1) has at least one selected from the group consisting of a partial structure represented by the following formula (1-1) and a partial structure represented by the following formula (1-2) as the partial structure including the partial structure (a1);

In formula (1-1) and formula (1-2), Ar ¹ and Ar ² are independently a divalent aromatic ring group; X ¹ and X ² are independently a single bond, -O-, -S-, -CO-, -NR ⁸ -, -COO-, -CONR ⁸ -, -NR ⁸ CONR ⁹ -, -SO ₂ -, -SO ₂ -O-, an alkanediyl group having 1 to 10 carbon atoms, or a group in which any methylene group in an alkanediyl group having 2 to 10 carbon atoms is substituted with -O-, -S-, -CO-, -NR ⁸ -, -COO-, -OCO-, -CONR ⁸ -, -NR ⁸ CO- or -NR ⁸ CONR ⁹ -; R ⁸ and R ⁹ are independently a hydrogen atom or a monovalent organic group; Ar ³ and Ar ⁴ are independently a trivalent aromatic ring group; R ¹ , R ² , n1, n2, m1 and m2 have the same meanings as in the formula (1); "*" represents a bonding bond.

4 . The liquid crystal alignment agent according to claim 1 , wherein the polymer ( P1 ) is at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide.

5. The liquid crystal alignment agent according to claim 1, wherein the polymer (P1) comprises, in the same molecule or in different molecules, a structural unit derived from at least one selected from the group consisting of a tetracarboxylic acid derivative having the partial structure (a1) and a diamine having the partial structure (a1), and a structural unit derived from a diamine having the partial structure (a2).

6 . The liquid crystal aligning agent according to claim 1 , further comprising a polymer having neither the partial structure (a1) nor the partial structure (a2).

7. A liquid crystal aligning agent comprising a polymer having a partial structure (a1) represented by the following formula (1) and the following compound,

In formula (1), ^R1 and ^R2 are independently monovalent substituents; n1 and n2 are independently 0 or 1; m1 is an integer from 0 to (n1×2+4); m2 is an integer from 0 to (n2×2+4); when there are multiple ^R1s , the multiple ^R1s are the same or different, and when there are multiple ^R2s , the multiple ^R2s are the same or different; "*" represents a bonding bond,

The compound has in one molecule a total of two or more of at least one group selected from the group consisting of a group represented by ^-OE1 , a thiol group, a protected thiol group, an amino group, a protected amino group, an oxetanyl group, a group represented by -Si( ^OR11 ) _r ( ^R12 ) _3-r , and a polymerizable carbon-carbon double bond group, wherein ^E1 is a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a monovalent leaving group, ^R11 and ^R12 are independently monovalent hydrocarbon groups having 1 to 10 carbon atoms, r is an integer of 1 to 3, and when r is 2 or 3, multiple ^R11s are the same or different, and when r is 1, multiple ^R12s are the same or different.

8 . A liquid crystal alignment film, formed using the liquid crystal alignment agent according to claim 1 .

9 . A liquid crystal element, comprising the liquid crystal alignment film according to claim 8 .

10. A method for manufacturing a liquid crystal alignment film, comprising:

A process of forming a coating film using the liquid crystal aligning agent according to any one of claims 1 to 7; and

A step of irradiating the coating film with light to impart liquid crystal alignment capability.

11. A method for manufacturing a liquid crystal element, comprising:

A step of forming a coating film on each of the conductive films of a pair of substrates having conductive films using the liquid crystal alignment agent as described in any one of claims 1 to 7;

A step of arranging a pair of substrates having the coating film formed thereon so that the coating film faces each other with a liquid crystal layer containing a photopolymerizable compound interposed therebetween to construct a liquid crystal cell; and

The step of irradiating the liquid crystal cell with light while a voltage is applied between the conductive films.