Liquid crystal alignment agent and its application, polyamic acid, polyamic acid ester and polyimide, diamine and tetracarboxylic dianhydride manufacturing method

Abstract

The present invention provides a liquid crystal alignment agent, a liquid crystal alignment film, a liquid crystal element, a polyamic acid, a polyamic acid ester, a polyimide, a method for producing a diamine, a method for producing a tetracarboxylic dianhydride, and a method for producing a polymer. The liquid crystal alignment agent can obtain a liquid crystal element with good liquid crystal orientation, excellent voltage retention characteristics, and suppressed degradation of display quality due to external forces. The liquid crystal alignment agent contains a polymer [A] having a partial structure (a) represented by formula (1) in the main chain. In formula (1), R 1 and R 2 Is the use of ‑C(R 5 )(R 6 )‑,‑O‑,‑S‑,‑CO‑,‑COO‑,‑NR 7 ‑, ‑NR 7 ‑NR 8 ‑, ‑NR 7 ‑CO‑O‑, ‑NR 7 ‑CO‑NR 8 -, an aromatic hydrocarbon ring, an aromatic heterocycle or a nitrogen-containing non-aromatic heterocycle and a divalent group bonded to the carbonyl group in formula (1). 3 and R 4 is a hydrogen atom, a halogen atom or an alkyl group having 1 to 3 carbon atoms, or represents R 3 With R 4 The ring structure formed by mutual connection. #imgabs0#

Description

Technical Field

[0001] The present invention relates to a liquid crystal alignment agent, a liquid crystal alignment film, a liquid crystal element, a polymer and a method for producing the same, and a method for producing a compound. Background Art

[0002] In the past, various driving modes have been developed as liquid crystal elements, with different electrode structures or physical properties of the liquid crystal molecules used. For example, various liquid crystal elements are known, such as twisted nematic (TN) type or super twisted nematic (STN) type, vertical alignment (VA) type, multi-domain vertical alignment (MVA) type, in-plane switching (IPS) type, fringe field switching (FFS) type, and optically compensated bend (OCB) type. These liquid crystal elements have a liquid crystal alignment film for aligning the liquid crystal molecules. Generally speaking, the liquid crystal alignment film is formed on the substrate by applying a liquid crystal alignment agent prepared by dissolving or dispersing a polymer component in an organic solvent to the surface of the substrate, preferably by heating.

[0003] In recent years, large-screen, high-definition LCD televisions have become mainstream. Furthermore, the widespread use of small display terminals such as smartphones and tablet personal computers (PCs) has further increased the demand for higher-quality liquid crystal elements. To meet this demand for higher quality, various liquid crystal alignment agents have been proposed (see, for example, Patent Document 1). Patent Document 1 discloses a method in which a liquid crystal alignment agent contains a polyimide or a polyimide precursor, and a cross-linking compound as a low-molecular-weight compound that increases the hardness of the liquid crystal alignment film.

[0004] [Prior art literature]

[0005] [Patent Document]

[0006] [Patent Document 1] International Publication No. 2020 / 171128 Summary of the Invention

[0007] [Problems to be solved by the invention]

[0008] As liquid crystal elements become increasingly sophisticated, quality requirements become more stringent. For example, liquid crystal elements are not only required to further improve liquid crystal orientation and voltage retention, but also to maintain display quality despite physical stresses such as vibration and tapping during transportation. In particular, the thinning of glass panels, which serve as the substrate for liquid crystal elements, is further increasing the physical stress applied to internal components. On the other hand, maintaining display quality simply by adding cross-linking compounds, as was previously the case, has become difficult.

[0009] The present invention has been made in view of the above-mentioned problems, and a main object of the present invention is to provide a liquid crystal aligning agent that can obtain a liquid crystal element having good liquid crystal orientation, excellent voltage holding characteristics, and suppressed degradation of display quality due to external force.

[0010] [Technical means to solve the problem]

[0011] The present inventors have conducted intensive research to solve the above-mentioned problems and have found that the above-mentioned problems can be solved by using a polymer having a specific carbon-carbon unsaturated structure, thereby completing the present invention. Specifically, the present invention provides the following means.

[0012] <1> A liquid crystal aligning agent comprising a polymer [A] having a partial structure (a) represented by the following formula (1) in its main chain,

[0013] [Chemistry 1]

[0014]

[0015] (In formula (1), R 1 and R 2 Each independently utilizes -C(R 5 )(R 6 )-, -O-, -S-, -CO-, -COO-, -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O-, -NR 7 -CO-NR 8 -, a divalent group formed by bonding an aromatic hydrocarbon ring, an aromatic heterocycle or a nitrogen-containing non-aromatic heterocycle to the carbonyl group in formula (1); R 3 and R 4 are independently a hydrogen atom, a halogen atom or an alkyl group having 1 to 3 carbon atoms, or R 3 With R 4 Combined with R 3 Bonded carbon and R 4 The carbon atoms to which they are bonded together form a ring structure; R 5 and R 6are independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 1 to 8 carbon atoms, or an alkoxy group having 1 to 8 carbon atoms; R 7 and R 8 are independently a hydrogen atom or a monovalent organic group; “*” represents a bonding bond).

[0016] <2> A liquid crystal alignment film formed using the liquid crystal aligning agent according to <1>.

[0017] <3> A liquid crystal element including the liquid crystal alignment film according to <2>.

[0018] <4> A polyamic acid, a polyamic acid ester, and a polyimide having a partial structure represented by the formula (1) in a main chain.

[0019] <5> A method for producing a diamine, comprising using a compound represented by the following formula (5) as a raw material to produce a diamine represented by the following formula (2),

[0020] [Chemistry 2]

[0021]

[0022] (In formula (5), R 9 is a single bond or a divalent organic group)

[0023] [Chemistry 3]

[0024]

[0025] (In formula (2), A 1 and A 2 are independently a single bond, a divalent alicyclic group or a divalent aromatic ring group; R 1 and R 2 Each independently utilizes -C(R 5 )(R 6 )-, -O-, -S-, -CO-, -COO-, -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O-, -NR 7 -CO-NR 8 -, a divalent organic group formed by bonding an aromatic hydrocarbon ring, an aromatic heterocycle or a nitrogen-containing non-aromatic heterocycle to the carbonyl group in formula (2); R 3 and R 4 are independently a hydrogen atom, a halogen atom or an alkyl group having 1 to 3 carbon atoms, or R 3 With R 4 Combined with R 3 Bonded carbon and R4 The carbon atoms to which they are bonded together form a ring structure; R 5 and R 6 are independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 1 to 8 carbon atoms, or an alkoxy group having 1 to 8 carbon atoms; R 7 and R 8 are independently a hydrogen atom or a monovalent organic group; m1 is an integer of 1 to 3; when m1 is 2 or 3, multiple R 1 ~R 4 the same as or different from each other).

[0026] <6> A method for producing tetracarboxylic dianhydride, comprising using the compound represented by the formula (5) as a raw material to produce tetracarboxylic dianhydride represented by the following formula (3) and formula (4),

[0027] [Chemistry 4]

[0028]

[0029] (In formula (3) and formula (4), A 3 and A 4 are independently a trivalent aromatic ring group or an aliphatic ring group; R 1 and R 2 Each independently utilizes -C(R 5 )(R 6 )-, -O-, -S-, -CO-, -COO-, -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O-, -NR 7 -CO-NR 8 -, a divalent organic group in which an aromatic hydrocarbon ring, an aromatic heterocycle or a nitrogen-containing non-aromatic heterocycle is bonded to the carbonyl group in formula (3) and formula (4); R 3 and R 4 are independently a hydrogen atom, a halogen atom or an alkyl group having 1 to 3 carbon atoms, or R 3 With R 4 Combined with R 3 Bonded carbon and R 4 The carbon atoms to which they are bonded together form a ring structure; R 5 and R 6 are independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 1 to 8 carbon atoms, or an alkoxy group having 1 to 8 carbon atoms; R 7 and R 8 are independently a hydrogen atom or a monovalent organic group; m2 is an integer of 1 to 3; n1 and n2 are independently an integer of 1 to 3; when m2 is 2 or 3, multiple R1 ~R 4 the same as or different from each other).

[0030] <7> A method for producing a polymer, comprising producing the polyamic acid, polyamic acid ester, and polyimide according to <4> by polymerizing monomers containing at least one compound selected from the group consisting of a diamine obtained by the production method according to <5> and a tetracarboxylic dianhydride obtained by the production method according to <6>.

[0031] [Effects of the Invention]

[0032] According to the liquid crystal aligning agent of the present invention, a liquid crystal element having good liquid crystal alignment, excellent voltage holding characteristics, and suppressed degradation of display quality even when subjected to external force (for example, external force due to vibration or impact) can be obtained. DETAILED DESCRIPTION

[0033] Liquid Crystal Alignment Agent

[0034] Hereinafter, each component contained in the liquid crystal aligning agent of this indication, and other components mix|blended arbitrarily as needed are demonstrated.

[0035] Furthermore, in this specification, the so-called "hydrocarbon group" includes the meaning of chain hydrocarbon groups, alicyclic hydrocarbon groups and aromatic hydrocarbon groups. The so-called "chain hydrocarbon group" refers to a straight-chain hydrocarbon group and a branched hydrocarbon group whose main chain does not contain a cyclic structure and is composed only of a chain structure. Among them, it can be saturated or unsaturated. The so-called "alicyclic hydrocarbon group" refers to a hydrocarbon group that only contains the structure of alicyclic hydrocarbon as a ring structure and does not contain an aromatic ring structure. Among them, it is not necessary to be composed only of the structure of alicyclic hydrocarbon, and also includes a group with a chain structure in a part thereof. The so-called "aromatic hydrocarbon group" refers to a hydrocarbon group that contains an aromatic ring structure as a ring structure. Among them, it is not necessary to be composed only of the aromatic ring structure, and also may contain a chain structure or an alicyclic hydrocarbon structure in a part thereof.

[0036] The so-called "main chain" refers to the longest "trunk" part in the atomic chain of the polymer. Furthermore, the "trunk" part is allowed to contain a ring structure. The so-called "side chain" refers to the part branching from the "trunk" of the polymer. The "aromatic ring" means an aromatic hydrocarbon ring and an aromatic heterocycle. The so-called "organic group" refers to an atomic group formed by removing any hydrogen atom from a carbon-containing compound (i.e., an organic compound). The "tetracarboxylic acid derivative" means a tetracarboxylic dianhydride, a tetracarboxylic acid diester and a tetracarboxylic acid diester dihalide.

[0037] The liquid crystal aligning agent of the present disclosure contains a polymer [A] having a partial structure (a) represented by the following formula (1) in its main chain.

[0038] [Chemistry 5]

[0039]

[0040] (In formula (1), R 1 and R 2 Each independently utilizes -C(R 5 )(R 6 )-, -O-, -S-, -CO-, -COO-, -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O-, -NR 7 -CO-NR 8 -, a divalent group formed by bonding an aromatic hydrocarbon ring, an aromatic heterocycle, or a nitrogen-containing non-aromatic heterocycle to the carbonyl group in formula (1). 3 and R 4 are independently a hydrogen atom, a halogen atom or an alkyl group having 1 to 3 carbon atoms, or R 3 With R 4 Combined with R 3 Bonded carbon and R 4 The carbon atoms to which they are bonded together form a ring structure. 5 and R 6 R is independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 8 carbon atoms, an alkenyl group having 1 to 8 carbon atoms, or an alkoxy group having 1 to 8 carbon atoms. 7 and R 8 are independently a hydrogen atom or a monovalent organic group. "*" represents a bond)

[0041] <Polymer [A]>

[0042] About partial structure (a)

[0043] In the formula (1), R 1 and R 2 To utilize -C(R 5 )(R 6 )-in the case of a divalent group bonded to the carbonyl group in the formula (1), R 5 and R 6 The alkyl group having 1 to 8 carbon atoms, the alkenyl group having 1 to 8 carbon atoms, and the alkoxy group having 1 to 8 carbon atoms represented by may be either linear or branched. 5 and R 6 A hydrogen atom or an alkyl group having 1 to 3 carbon atoms is also preferred, and a hydrogen atom (i.e., -C(R 5 )(R 6 )- is a methylene group).

[0044] In the formula (1), R 1 and R 2To use -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O- and -NR 7 -CO-NR 8 - In the case of a divalent group bonded to the carbonyl group in the formula (1), R 7 and R 8 The monovalent organic group represented is preferably a monovalent hydrocarbon group having 1 to 10 carbon atoms, or a monovalent leaving group (hereinafter also simply referred to as a "leaving group") that is released by heat or light.

[0045] In R 7 and R 8 When the monovalent organic group represented is a monovalent hydrocarbon group, specific examples of the hydrocarbon group include an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 4 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, and an aralkyl group having 6 to 10 carbon atoms. Among these, an alkyl group having 1 to 3 carbon atoms and a phenyl group are preferred, and an alkyl group having 1 to 3 carbon atoms is more preferred.

[0046] In R 7 and R 8 When the monovalent organic group represented is a monovalent detachable group, the detachable group is preferably a thermally detachable group that detaches by heat (preferably heating during film formation). Specific examples of thermally detachable groups include tert-butoxycarbonyl (Boc), benzyloxycarbonyl, 1,1-dimethyl-2-haloethyloxycarbonyl, allyloxycarbonyl, and 2-(trimethylsilyl)ethoxycarbonyl. Among these, the Boc group is particularly preferred because it has excellent thermal detachability and can reduce the amount of detached structures remaining in the film.

[0047] Among them, R 7 and R 8 It is preferably a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a monovalent thermally detachable group, and more preferably a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a tert-butoxycarbonyl group.

[0048] In R 1 and R 2In the case of a group bonded to the carbonyl group in formula (1) via an aromatic hydrocarbon ring, aromatic heterocycle, or nitrogen-containing non-aromatic heterocycle, examples of the aromatic hydrocarbon ring include a benzene ring, a naphthalene ring, and an anthracene ring. Examples of the aromatic heterocycle include nitrogen-containing aromatic heterocycles, oxygen-containing aromatic heterocycles, and sulfur-containing aromatic heterocycles. Specific examples of these include nitrogen-containing aromatic heterocycles such as pyridine, pyrimidine, pyridazine, and pyrazine rings; oxygen-containing aromatic heterocycles such as furan rings; and sulfur-containing aromatic heterocycles such as thiophene rings. Examples of nitrogen-containing non-aromatic heterocycles include piperidine and piperazine rings. These rings may have substituents. Examples of the substituents include alkyl groups having 1 to 3 carbon atoms, alkoxy groups having 1 to 3 carbon atoms, halogen atoms, hydrogen atoms, and cyano groups.

[0049] R 1 and R 2 As long as the -C(R 5 )(R 6 )-, -O-, -S-, -CO-, -COO-, -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O-, -NR 7 -CO-NR 8 -, an aromatic hydrocarbon ring, an aromatic heterocycle or a nitrogen-containing non-aromatic heterocycle bonded to the carbonyl group in formula (1), and there is no particular limitation on the other partial structures. 1 and R 2 When -COO- is bonded to the carbonyl group in the formula (1), R 1 and R 2 The oxygen atom can be bonded to the carbonyl group in the formula (1), or the carbon atom can be bonded. 1 and R 2 Utilize-NR 7 When -CO-O- is bonded to the carbonyl group in the formula (1), R 1 and R 2 The carbonyl group in the formula (1) may be bonded to the carbonyl group via a nitrogen atom or a carbon atom.

[0050] As R 1 and R 2 Specific examples include: -C(R 5 )(R 6 )-, -O-, -S-, -CO-, -COO-, -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O-, -NR 7 -CO-NR8 -, a divalent chain hydrocarbon group, a divalent aromatic hydrocarbon ring group, a divalent aromatic heterocyclic group, and a divalent nitrogen-containing non-aromatic heterocyclic group. 1 and R 2 It can also be formed by -O-, -S-, -CO-, -COO-, -NR- 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O-, -NR 7 -CO-NR 8 - or a divalent organic group substituted with a heterocyclic group.

[0051] The R is advantageous in that it can improve the voltage holding ratio (VHR) of the liquid crystal element, can obtain a liquid crystal element with high reliability with little decrease in voltage holding ratio even in long-term driving, can obtain a liquid crystal element showing good liquid crystal orientation, and has a high effect of suppressing the degradation of display quality caused by vibration or knocking. 1 and R 2 One or both of them are preferably a group having a chain hydrocarbon structure with a carbon number of 1 or more or a divalent nitrogen-containing non-aromatic heterocyclic group. 1 and R 2 One or both of them are preferably a divalent chain hydrocarbon group having 1 or more carbon atoms, or a chain hydrocarbon group having 2 or more carbon atoms having any methylene groups which are not adjacent to each other, and are preferably connected via -O-, -S-, -CO-, -COO-, -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O- or -NR 7 -CO-NR 8 -substituted divalent group (wherein, using -C(R 5 )(R 6 )-, -O-, -S-, -CO-, -COO-, -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O- or -NR 7 -CO-NR 8 -bonded to the carbonyl group in the formula (1), or a divalent nitrogen-containing non-aromatic heterocyclic group. 1 and R 2One or both of them are particularly preferably a divalent chain hydrocarbon group having 1 or more carbon atoms, or a chain hydrocarbon group having 2 or more carbon atoms having any methylene groups which are not adjacent to each other, through -O-, -S-, -CO-, -COO-, -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O- or -NR 7 -CO-NR 8 -substituted divalent group. 5 、R 6 、R 7 and R 8 For specific examples and preferred examples, the above description can be cited.

[0052] In R 1 、R 2 When it is a divalent chain hydrocarbon group, the chain hydrocarbon group may be saturated or unsaturated, and may be linear or branched. In terms of improving the voltage holding ratio of the liquid crystal element, obtaining a liquid crystal element with high reliability that has little decrease in voltage holding ratio even when driven for a long time, obtaining a liquid crystal element that exhibits good liquid crystal orientation, and suppressing the decrease in display quality due to vibration or impact, R 1 、R 2 The chain hydrocarbon group represented by is preferably an alkanediyl group, more preferably a straight-chain alkanediyl group. 1 、R 2 When R is a divalent chain hydrocarbon group, from the viewpoint of obtaining a liquid crystal element showing a high voltage holding ratio and a liquid crystal element showing good liquid crystal orientation, the carbon number of the chain hydrocarbon group is preferably 2 or more, more preferably 3 or more. In addition, from the viewpoint of achieving both an improvement in film strength (and thus an improvement in friction resistance) and an improvement in the voltage holding ratio of the liquid crystal element, R 1 、R 2 When R is a chain hydrocarbon group 1 、R 2 The carbon number of is preferably 20 or less, more preferably 15 or less, and further preferably 10 or less.

[0053] When R 1 、R 2 Under the condition that any methylene groups possessed by the chain hydrocarbon group having 2 or more carbon atoms are not adjacent, the carbonyl group is formed by -O-, -S-, -CO-, -COO-, -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O- or -NR 7 -CO-NR8 -substituted divalent group (hereinafter also referred to as "divalent group A"), R 1 and R 2 One or both of them are preferably a group represented by the following formula (6).

[0054] -R 10 -X 1 -* 1 ···(6)

[0055] (In formula (6), R 10 X is an alkanediyl group. 1 -O-, -S-, -CO-, -COO-, -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O- or -NR 7 -CO-NR 8 -. "* 1 " represents a bond to the carbonyl group in formula (1). R 7 and R 8 Same meaning as formula (1)

[0056] In the formula (6), R 10 The alkanediyl group represented by is preferably linear. The number of carbon atoms in the alkanediyl group is preferably 1 to 10, more preferably 2 to 10, and even more preferably 2 to 5.

[0057] In R 1 and R 2 In the case of a divalent nitrogen-containing non-aromatic heterocyclic group, the divalent nitrogen-containing non-aromatic heterocyclic group is preferably a substituted or unsubstituted 1,4-piperidinediyl group or a substituted or unsubstituted 1,4-piperazinediyl group.

[0058] In the formula (1), R 3 and R 4 Preferably, a hydrogen atom, a fluorine atom or a methyl group, or represents R 3 With R 4 Combined with R 3 Bonded carbon and R 4 The carbon atoms bonded together form a ring structure. 3 With R 4 Examples of the ring structure formed by mutual bonding include cycloolefin rings having 5 to 10 ring members. Among them, the ring structure is preferably a cycloolefin ring having 5 to 8 ring members. Among these, R 3 and R 4 A hydrogen atom, a fluorine atom or a methyl group is preferred, and a hydrogen atom is particularly preferred.

[0059] -R in the formula (1) 4 C=CR 3 The group represented by - may be a cis-type or a trans-type. In terms of improving the film strength, -R in the formula (1) 4 C=CR 3 The group represented by - is preferably a cis-type.

[0060] Among them, the partial structure (a) is preferably a structure represented by the following formula (1-1) or the following formula (1-2).

[0061] [Chemistry 6]

[0062]

[0063] (In formula (1-1), R 11 and R 13 It is R 11 is a hydrogen atom or a monovalent organic group and R 13 is a single bond or an alkanediyl group, or represents R 11 and R 13 Combined with R 11 The nitrogen atoms bonded together form a nitrogen-containing non-aromatic heterocyclic structure. 12 and R 14 It is R 12 is a hydrogen atom or a monovalent organic group and R 14 is a single bond or an alkanediyl group, or represents R 12 and R 14 Combined with R 12 The nitrogen atoms bonded together form a nitrogen-containing non-aromatic heterocyclic structure. 3 and R 4 Each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 3 carbon atoms. "*" represents a bonding bond.

[0064] In formula (1-2), R 15 and R 16 R are independently a single bond or an alkanediyl group. 3 and R 4 (A) each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 3 carbon atoms. (“*” represents a bond)

[0065] In the above formula (1-1) and formula (1-2), regarding R 11 、R 12 The monovalent organic group represented by can be exemplified by the following: 7 and R 8 The same groups as those exemplified in the description of . 3 and R 4 , which can be listed as R in the formula (1)3 and R 4 The groups are the same as those exemplified in the description of .

[0066] In R 13 、R 14 In the case of an alkanediyl group, a linear one is preferred, and a linear alkanediyl group having 1 to 5 carbon atoms is more preferred. 11 and R 13 The ring structure formed by combining with each other, and R 12 and R 14 The ring structure formed by bonding to each other is preferably a substituted or unsubstituted 1,4-piperidinediyl group or a substituted or unsubstituted 1,4-piperazinediyl group.

[0067] In polymer [A], from the viewpoint of obtaining a liquid crystal element exhibiting good liquid crystal orientation, high VHR, and high reliability, the content ratio of the structural units derived from monomers having the partial structure (a) relative to the total amount of monomer units contained in polymer [A] is preferably 2 mol% or more. From this viewpoint, the content ratio of the structural units derived from monomers having the partial structure (a) relative to the total amount of monomer units contained in polymer [A] is more preferably 5 mol% or more, and even more preferably 7 mol% or more.

[0068] The content ratio of the structural unit derived from the monomer having the partial structure (a) can be appropriately set according to the main chain of the polymer [A], and is, for example, 60 mol% or less, preferably 50 mol% or less, relative to the total amount of the monomer units contained in the polymer [A]. Furthermore, in the polymer [A], the structural unit derived from the monomer having the partial structure (a) may be only one type, or may be two or more types.

[0069] The main skeleton of the polymer [A] is not particularly limited. In terms of forming a liquid crystal alignment film having high affinity with liquid crystals, high mechanical strength, and high reliability, the polymer [A] is preferably at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide.

[0070] The method for producing polymer [A] is not particularly limited as long as the partial structure (a) can be introduced into the main chain of the polymer. In terms of ease of introducing the partial structure (a) into the main chain of the polymer, polymer [A] is preferably produced by a method of polymerizing a monomer having the partial structure (a) in the main chain. In terms of forming a liquid crystal alignment film having high affinity with liquid crystals and high mechanical strength, the monomer having the partial structure (a) is preferably at least one selected from the group consisting of a diamine compound having the partial structure (a) (hereinafter also referred to as a "specific diamine") and a tetracarboxylic dianhydride having the partial structure (a) (hereinafter also referred to as a "specific acid anhydride").

[0071] (Specific diamine)

[0072] The specific diamine may be a monomer having the partial structure (a) and two primary amino groups, and other partial structures are not particularly limited. Specifically, the specific diamine is preferably a compound represented by the following formula (2).

[0073] [Chemistry 7]

[0074]

[0075] (In formula (2), A 1 and A 2 Each of them is independently a single bond, a divalent alicyclic group or a divalent aromatic ring group. m1 is an integer of 1 to 3. 1 、R 2 、R 3 and R 4 It has the same meaning as the above formula (1). When m1 is 2 or 3, multiple R 1 ~R 4 the same or different from each other)

[0076] In the formula (2), A 1 and A 2 The divalent alicyclic group represented is preferably a group formed by removing two hydrogen atoms from the ring portion of a substituted or unsubstituted alicyclic hydrocarbon ring. Examples of the alicyclic hydrocarbon ring include a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, and a cycloheptane ring. Examples of substituents introduced into the ring portion of the alicyclic hydrocarbon ring include an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, and a halogen atom.

[0077] A 1 and A 2 The divalent aromatic ring group represented is a group formed by removing two hydrogen atoms from a substituted or unsubstituted aromatic ring. The aromatic ring is an aromatic hydrocarbon ring or an aromatic heterocycle, preferably an aromatic hydrocarbon ring or a nitrogen-containing aromatic heterocycle. Examples of substituents introduced into the aromatic ring include alkyl groups having 1 to 5 carbon atoms, alkoxy groups having 1 to 5 carbon atoms, and halogen atoms.

[0078] As A 1 and A 2 Specific examples of divalent aromatic ring groups include divalent aromatic hydrocarbon ring groups formed by removing arbitrary hydrogen atoms from a ring portion of a benzene ring, a biphenyl ring, a naphthalene ring, or an anthracene ring; and divalent nitrogen-containing aromatic heterocyclic groups formed by removing two arbitrary hydrogen atoms from a ring portion of a pyridine ring, a pyrimidine ring, a pyridazine ring, or a pyrazine ring. From the perspective of achieving high density of a liquid crystal alignment film, A 1 、A 2The divalent aromatic ring group represented is preferably a substituted or unsubstituted phenylene group, a biphenylene group, or a pyridinediyl group, and more preferably a substituted or unsubstituted phenylene group.

[0079] From the perspective of obtaining a liquid crystal element with high reliability that has little decrease in voltage holding ratio (VHR) even in long-term driving, and from the perspective of obtaining a liquid crystal element that exhibits good liquid crystal orientation, A 1 and A 2 It is preferably a divalent alicyclic group or a divalent aromatic ring group, and more preferably a divalent aromatic ring group.

[0080] From the viewpoint of liquid crystal orientation and ease of synthesis, m1 is preferably 1 or 2. Furthermore, from the viewpoint of enhancing the improvement effect brought about by the introduction of the partial structure (a), m1 is preferably 2 or greater. From the viewpoint of enhancing the liquid crystal orientation and ease of synthesis, and enhancing the improvement effect of the voltage holding ratio brought about by the introduction of the partial structure (a), m is particularly preferably 2.

[0081] Preferred specific examples of the specific diamine include a compound represented by the following formula (2-1) and a compound represented by the following formula (2-2).

[0082] [Chemistry 8]

[0083]

[0084] (In formula (2-1) and formula (2-2), Ar 1 and Ar 2 are independently a divalent aromatic ring group. m1 is an integer from 1 to 3. 3 、R 4 、R 11 、R 12 、R 13 、R 14 、R 15 and R 16 (Has the same meaning as the above formula (1-1) and formula (1-2))

[0085] Specific examples of the specific diamine include compounds represented by the following formulas (3-1) to (3-30). In the compounds represented by the following formulas (3-1) to (3-30), the carbon-carbon unsaturated bond between the two carbonyl groups does not have a fixed structural isotype and may be a cis-isomer or a trans-isomer.

[0086] [Chemistry 9]

[0087]

[0088] [Chemistry 10]

[0089]

[0090] [Chemistry 11]

[0091]

[0092] [Chemistry 12]

[0093]

[0094] [Chemistry 13]

[0095]

[0096] [Chemistry 14]

[0097]

[0098] (Synthesis of specific diamine)

[0099] The synthesis method of the specific diamine is not particularly limited. The specific diamine can be produced, for example, by the following method: maleic anhydride and a compound having the same structure as "-R" in the formula (2) are reacted with each other. 1 -A 1 -NH2" corresponding to the partial structure of the amine compound reaction (method 1A); fumaryl chloride, and having the same as the "-R 1 -A 1 -NH2" corresponding to the partial structure of the amine compound (method 2A). In addition, the specific diamine can also be produced using a compound represented by the following formula (5) as a raw material (method 3A). From an industrial point of view, it is ideal to obtain a useful diamine with a small number of steps. In this regard, according to method 3A, it is preferred in that two or more partial structures (a) can be introduced into the specific diamine with a small number of steps.

[0100] [Chemistry 15]

[0101]

[0102] (In formula (5), R 9 is a single bond or a divalent organic group)

[0103] In method 3A, the compound represented by the formula (5) and the compound having the same residue as "-R 1 -A 1 -NH2" corresponding to the partial structure of the amine compound in the solvent as needed. The solvent is preferably an organic solvent that can dissolve the raw materials. In method 3A, the reaction temperature is, for example, 0 ° C to 80 ° C, and the reaction time is, for example, 30 minutes to 12 hours.

[0104] In the formula (5), R9 Examples of the divalent organic group include divalent hydrocarbon groups having 1 to 20 carbon atoms and divalent groups containing -O-, -S-, etc. between carbon-carbon bonds of the hydrocarbon groups. For example, by reacting the compound represented by the above formula (5) with the compound represented by the following formula (7), a compound represented by the following formula (8) can be obtained as a specific diamine.

[0105] [Chemistry 16]

[0106]

[0107] (In the process, R 9 A is a single bond or a divalent organic group. 1 It has the same meaning as the formula (2), R 1 has the same meaning as the formula (1)

[0108] (Specific acid anhydride)

[0109] The specific acid anhydride may be a monomer having the partial structure (a) and two acid anhydride groups, and other partial structures are not particularly limited. Specifically, the specific acid anhydride is preferably at least one selected from the group consisting of a compound represented by the following formula (3) and a compound represented by the following formula (4).

[0110] [Chemistry 17]

[0111]

[0112] (In formula (3) and formula (4), A 3 and A 4 Each independently represents a trivalent aromatic ring group or an aliphatic ring group. m2 represents an integer of 1 to 3. n1 and n2 represent an integer of 1 to 3. 1 、R 2 、R 3 and R 4 It has the same meaning as the above formula (1). When m2 is 2 or 3, multiple R 1 ~R 4 the same or different from each other)

[0113] In the above formula (3) and formula (4), A 3 and A 4 Examples of the trivalent aliphatic cyclic group include groups formed by removing three hydrogen atoms from an alicyclic hydrocarbon ring such as a cyclobutane ring, a cyclopentane ring, a cyclohexane ring, or a cycloheptane ring. These alicyclic hydrocarbon rings may have substituents. Examples of such substituents include alkyl groups having 1 to 5 carbon atoms, alkoxy groups having 1 to 5 carbon atoms, and halogen atoms.

[0114] A 3 and A 4The trivalent aromatic ring group represented is a group formed by removing three hydrogen atoms from the ring portion of a substituted or unsubstituted aromatic ring. The aromatic ring is an aromatic hydrocarbon ring or an aromatic heterocycle, preferably an aromatic hydrocarbon ring or a nitrogen-containing aromatic heterocycle. As substituents introduced into the ring portion of the aromatic ring, there can be listed: an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, a halogen atom, etc. From the perspective of achieving high density of the liquid crystal alignment film, A 3 、A 4 The trivalent aromatic ring group represented is preferably a group having a benzene ring, a biphenyl ring or a pyridine ring, and more preferably a group having a benzene ring.

[0115] From the perspective of obtaining a liquid crystal element with high reliability that has little decrease in voltage holding ratio (VHR) even in long-term driving, and from the perspective of obtaining a liquid crystal element that exhibits good liquid crystal orientation, A 3 and A 4 It is preferably a trivalent aromatic ring group, and more preferably a trivalent group having a benzene ring.

[0116] From the viewpoint of liquid crystal orientation and ease of synthesis, m2 is preferably 1 or 2. From the viewpoint of enhancing the improvement effect by introducing the partial structure (a), m2 is preferably 2 or more.

[0117] Preferred specific examples of the specific acid anhydride include a compound represented by the following formula (3-1), a compound represented by the following formula (3-2), a compound represented by the following formula (4-1), and a compound represented by the following formula (4-2).

[0118] [Chemistry 18]

[0119]

[0120] (In formula (3-1) and formula (3-2), Ar 3 and Ar 4 are independently trivalent aromatic ring groups. m2 is an integer from 1 to 3. 3 、R 4 、R 11 、R 12 、R 13 、R 14 、R 15 and R 16 (Has the same meaning as the above formula (1-1) and formula (1-2))

[0121] [Chemistry 19]

[0122]

[0123] (In formula (4-1) and formula (4-2), m2 is an integer of 1 to 3. n1 and n2 are each independently an integer of 1 to 3. R 3 、R 4 、R 11 、R 12 、R 13 、R 14 、R 15 and R 16 (Has the same meaning as the above formula (1-1) and formula (1-2))

[0124] In the above formulas (3-1), (3-2), (4-1) and (4-2), from the viewpoint of ease of synthesis of the compound, R 13 、R 14 、R 15 and R 16 It is preferably a single bond.

[0125] Specific examples of specific acid anhydrides include compounds represented by the following formulas (4-1) to (4-3). In the compounds represented by the following formulas (4-1) to (4-3), the carbon-carbon unsaturated bond between the two carbonyl groups does not have a fixed structural isomer and may be a cis-isomer or a trans-isomer.

[0126] [Chemistry 20]

[0127]

[0128] (Synthesis of Specific Acid Anhydride)

[0129] The method for synthesizing the specific acid anhydride is not particularly limited. The specific acid anhydride can be produced, for example, by the following method: fumaryl chloride and a compound having the same structure as "-R" in the formula (3) or (4) are reacted with each other. 1 -acid anhydride group" (method 1B). In addition, the specific acid anhydride can also be produced by using a compound represented by the following formula (5) as a raw material (method 2B). From an industrial point of view, it is ideal to obtain useful tetracarboxylic dianhydride with a small number of steps. In this regard, according to method 2B, it is preferred in that two or more partial structures (a) can be introduced into the specific acid anhydride with a small number of steps.

[0130] [Chemistry 21]

[0131]

[0132] (In formula (5), R 9 is a single bond or a divalent organic group)

[0133] In method 2B, the compound represented by the formula (5) and the compound having the same structure as "-R1 -acid anhydride group" corresponds to the partial structure of the amine compound in a solvent as needed. The solvent is preferably an organic solvent that can dissolve the raw materials. In method 2B, the reaction temperature is, for example, 0°C to 80°C, and the reaction time is, for example, 30 minutes to 12 hours.

[0134] In the formula (5), R 9 Examples of the divalent organic group include divalent hydrocarbon groups having 1 to 20 carbon atoms and divalent groups containing -O-, -S-, etc. between carbon-carbon bonds of the hydrocarbon groups. For example, by reacting the compound represented by the above formula (5) with the compound represented by the following formula (9), the compound represented by the following formula (10) can be obtained as a specific acid anhydride.

[0135] [Chemistry 22]

[0136]

[0137] (In the process, R 9 A is a single bond or a divalent organic group. 5 is a single bond or an alkanediyl group. 1 It has the same meaning as the above formula (1). n1 is an integer from 1 to 3)

[0138] <Polyamic acid>

[0139] When the polymer [A] is a polyamic acid, examples of the polyamic acid (hereinafter also referred to as "polyamic acid [A]") include: [1] a method of reacting a tetracarboxylic dianhydride containing a specific acid dianhydride with a diamine compound; [2] a method of reacting a tetracarboxylic dianhydride with a diamine compound containing a specific diamine. Furthermore, the method [1] and the method [2] may be combined.

[0140] (Tetracarboxylic dianhydride)

[0141] When synthesizing polyamic acid [A], as tetracarboxylic dianhydride, one species may be used alone, or two or more species may be used in combination. The tetracarboxylic dianhydride used in the synthesis of polyamic acid [A] may be only a specific acid dianhydride, or may include a tetracarboxylic dianhydride not having partial structure (a) (hereinafter also referred to as "other acid dianhydride"). Examples of other acid dianhydrides include chain aliphatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, and aromatic tetracarboxylic dianhydride.

[0142] Specific examples of other acid dianhydrides include chain aliphatic tetracarboxylic dianhydrides such as 1,2,3,4-butanetetracarboxylic dianhydride and ethylenediaminetetraacetic dianhydride; alicyclic tetracarboxylic dianhydrides include 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 5-(2,5-dioxotetrahydrofuran-3-yl)-3a,4,5,9b-tetrahydronaphtho[1,2-c]furan-1,3-dione, 5-(2,5-dioxotetrahydrofuran-3-yl)-8-methyl-3a,4,5,9b-tetrahydronaphtho[1,2-c ]furan-1,3-dione, 2,4,6,8-tetracarboxybicyclo[3.3.0]octane-2:4,6:8-dianhydride, cyclopentanetetracarboxylic dianhydride, cyclohexanetetracarboxylic dianhydride, 3,5,6-tricarboxy-2-carboxymethylnorbornane-2:3,5:6-dianhydride, etc.; aromatic tetracarboxylic dianhydrides include: pyromellitic dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, ethylene glycol ditriphthalic anhydride, 4,4'-carbonyldiphthalic anhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, etc., and in addition, the tetracarboxylic dianhydrides described in Japanese Patent Laid-Open No. 2010-97188 can be used.

[0143] In order to obtain a liquid crystal alignment film having high solubility and exhibiting good liquid crystal orientation and electrical properties, the other acid dianhydride used in the synthesis of the polyamic acid [A] preferably comprises at least one selected from the group consisting of linear aliphatic tetracarboxylic dianhydride and alicyclic tetracarboxylic dianhydride, and more preferably comprises alicyclic tetracarboxylic dianhydride. The proportion of alicyclic tetracarboxylic dianhydride used relative to the total amount of tetracarboxylic dianhydride used in the synthesis of the polyamic acid [A] is preferably 20 mol% or more, more preferably 40 mol% or more, and even more preferably 50 mol% or more.

[0144] When the polyamic acid [A] is produced by the method [1] above, the proportion of the specific acid dianhydride used is preferably 20 mol% or more, more preferably 30 mol% or more, and even more preferably 40 mol% or more, relative to the total amount of tetracarboxylic dianhydride used in the synthesis of the polyamic acid [A].

[0145] (Diamine compound)

[0146] When synthesizing polyamic acid [A], as a diamine compound, one type may be used alone, or two or more types may be used in combination. The diamine compound used in the synthesis of polyamic acid [A] may be only a specific diamine, or may include a diamine compound not having partial structure (a) (hereinafter also referred to as "other diamine"). Examples of other diamines include linear aliphatic diamines, alicyclic diamines, aromatic diamines, and diaminoorganosiloxanes.

[0147] Specific examples of other diamines include chain aliphatic diamines such as meta-xylylenediamine and hexamethylenediamine; alicyclic diamines such as 1,4-diaminocyclohexane and 4,4'-methylenebis(cyclohexylamine); and aromatic diamines such as p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4-aminophenyl-4-aminobenzoate, 4,4'-diaminoazobenzene, 3,5-diaminobenzoic acid, 1,5-bis(4-aminophenoxy)pentane, 1,2-bis(4-aminophenoxy)ethane, 1,3-bis(4-aminophenoxy)propane, 1,6-bis(4-aminophenoxy)hexane, 6,6'-(pentamethylenedioxy)bis(3-aminopyridine), N,N'-bis(5 -amino-2-pyridyl)-N,N'-di(tert-butoxycarbonyl)ethylenediamine, bis[2-(4-aminophenyl)ethyl]adipic acid, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylamine, 4,4'-diaminodiphenylethyl urea, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis(4-aminophenyl)hexafluoropropane, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 4,4'-(phenylenediisopropylidene)dianiline, 2,6-diaminopyrimidine, 2,4-diaminopyrimidine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, 3,6-diaminoacridine, a monomer containing a diphenylamine structure, the following formula (F-1):

[0148] [Chemistry 23]

[0149]

[0150] (In formula (F-1), R 21 and R 22 are independently an alkanediyl group. 23 is a hydrogen atom, an alkyl group with 1 to 3 carbon atoms, or a protecting group. r1 is an integer from 1 to 3. When r1 is 2 or 3, multiple R 22 Mutually identical or different, multiple R 23 the same or different from each other)

[0151] Main chain diamines such as the compounds represented;

[0152] Hexadecyloxy-2,4-diaminobenzene, octadecyloxy-2,4-diaminobenzene, octadecyloxy-2,5-diaminobenzene, cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-2,4-diaminobenzene, cholesteryloxy-2,4-diaminobenzene, 3,5-diaminobenzoic acid cholesteryl ester, 3,5-diaminobenzoic acid cholesteryl ester, 3,5- Lanostanyl diaminobenzoate, 3,6-bis(4-aminobenzoyloxy)cholestane, 3,6-bis(4-aminophenoxy)cholestane, 4-(4'-trifluoromethoxybenzoyloxy)cyclohexyl-3,5-diaminobenzoate, 1,1-bis(4-((aminophenyl)methyl)phenyl)-4-butylcyclohexane, 5ξ-cholestane-3-yl 3,5-diaminobenzoate, the following formula (E-1):

[0153] [Chemistry 24]

[0154]

[0155] (In formula (E-1), X I and X II Each independently represents a single bond, -O-, *-COO-, or *-OCO- (where "*" represents a bond to the diaminophenyl side). I It is an alkanediyl group having 1 to 3 carbon atoms. II is a single bond or an alkanediyl group having 1 to 3 carbon atoms. III is an alkyl group, alkoxy group, fluoroalkyl group, or fluoroalkoxy group having 1 to 20 carbon atoms. a is 0 or 1. b is an integer from 0 to 3. c is an integer from 0 to 2. d is 0 or 1. (where 1≦a+b+c≦3)

[0156] The compounds represented by side chain diamines, etc.

[0157] Examples of the diaminoorganosiloxane include 1,3-bis(3-aminopropyl)-tetramethyldisiloxane.

[0158] Examples of the compound represented by formula (F-1) include compounds represented by the following formulas (F-1-1) to (F-1-3). Examples of the compound represented by formula (E-1) include compounds represented by the following formulas (E-1-1) to (E-1-4). Other diamines may be used alone or in combination of two or more. In the formula, "Boc" represents t-Butyloxycarbonyl (hereinafter the same).

[0159] [Chemistry 25]

[0160]

[0161] When the polyamic acid [A] is produced by the method [2] above, the proportion of the specific diamine used is preferably 20 mol% or more, more preferably 30 mol% or more, and even more preferably 40 mol% or more, relative to the total amount of the diamine compounds used in the synthesis of the polyamic acid [A].

[0162] (Synthesis of Polyamic Acid)

[0163] Polyamic acid [A] can be obtained by reacting tetracarboxylic dianhydride and a diamine compound, optionally together with a molecular weight modifier. One preferred method for producing polyamic acid [A] includes reacting tetracarboxylic dianhydride and a diamine compound using a monomer containing at least one selected from the group consisting of the specific diamine obtained by method 3A and the specific acid dianhydride obtained by method 2B.

[0164] In the synthesis reaction of polyamic acid [A], the ratio of tetracarboxylic dianhydride to diamine compound is preferably such that the anhydride group of tetracarboxylic dianhydride is 0.2 to 2 equivalents per 1 equivalent of the amino group of the diamine compound. Examples of molecular weight modifiers include 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 modifier is preferably used in an amount of 20 parts by mass or less relative to a total of 100 parts by mass of the tetracarboxylic dianhydride and diamine compound used.

[0165] The synthesis reaction of polyamic acid [A] is preferably carried out in an organic solvent. The reaction temperature at this time is preferably -20°C to 150°C, and the reaction time is preferably 0.1 hour to 24 hours. As the organic solvent used for the reaction, for example, there can be mentioned: aprotic polar solvents, phenolic solvents, alcoholic solvents, ketone solvents, ester solvents, ether solvents, halogenated hydrocarbons, hydrocarbons, etc. Among these, it is preferred to use one or more selected from the group consisting of N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, tetramethylurea, hexamethylphosphoric triamide, m-cresol, xylenol and halogenated phenol as the reaction solvent, or use a mixture of one or more of these solvents and other organic solvents (such as butyl cellosolve, diethylene glycol diethyl ether, etc.). It is preferable that the usage-amount of an organic solvent is set as the amount which makes the total amount of tetracarboxylic dianhydride and a diamine compound into 0.1 mass % - 50 mass % with respect to the whole amount of a reaction solution.

[0166] In this manner, a polymer solution in which the polyamic acid [A] is dissolved can be obtained. The polymer solution can be used for the preparation of a liquid crystal aligning agent as it is, or can be used for the preparation of a liquid crystal aligning agent after the polyamic acid [A] contained in the polymer solution is separated.

[0167] Polyamic acid ester

[0168] When the polymer [A] is a polyamic acid ester, the polyamic acid ester (hereinafter also referred to as "polyamic acid ester [A]") can be obtained, for example, by the following methods: [I] a method of reacting polyamic acid [A] with an esterifying agent; [II] a method of reacting a tetracarboxylic acid diester with a diamine compound containing a specific diamine; [III] a method of reacting a tetracarboxylic acid diester dihalide with a diamine compound containing a specific diamine. Polyamic acid ester [A] may have only an amic acid ester structure or a partial ester having an amic acid structure and an amic acid ester structure. The reaction solution in which the polyamic acid ester [A] is dissolved may be directly used for the preparation of a liquid crystal aligning agent, or may be used for the preparation of a liquid crystal aligning agent after separating the polyamic acid ester [A] contained in the reaction solution.

[0169] Polyimide

[0170] When the polymer [A] is a polyimide, the polyimide (hereinafter also referred to as "polyimide [A]") can be obtained, for example, by dehydrating and ring-closing the polyamic acid [A] synthesized in the above manner and imidizing it. The polyimide [A] may be a completely imidized product in which all the amic acid structures of the polyamic acid [A] as its precursor are dehydrated and ring-closed, or it may be a partially imidized product in which only a part of the amic acid structure is dehydrated and ring-closed, and the amic acid structure and the imide ring structure coexist. The polyimide [A] preferably has an imidization rate of 20% to 99%, more preferably 30% to 90%. Furthermore, the imidization rate is expressed as a percentage to represent the ratio of the number of imide ring structures to the total number of amic acid structures and the number of imide ring structures of the polyimide. Here, a part of the imide ring may be an isoimide ring.

[0171] The dehydration ring-closure of polyamic acid [A] is preferably carried out by dissolving polyamic acid [A] in an organic solvent, adding a dehydrating agent and a dehydration ring-closure catalyst to the solution, and optionally heating. In this method, 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 used is preferably 0.01 to 20 mol per 1 mol of the amic acid structure of polyamic acid [A]. A tertiary amine such as pyridine, coltidine, dimethylpyridine, or triethylamine can be used as the dehydration ring-closure catalyst. The amount of the dehydration ring-closure catalyst used is preferably 0.01 to 10 mol per 1 mol of the dehydrating agent used. Examples of the organic solvent used in the dehydration ring-closure reaction include those exemplified as organic solvents used for the synthesis of polyamic acid [A]. The reaction temperature for the dehydration ring-closure reaction is preferably 0°C to 180°C. The reaction time is preferably 1.0 to 120 hours. In addition, the reaction solution containing the polyimide [A] may be used for preparation of a liquid crystal aligning agent as it is, and you may use it for preparation of a liquid crystal aligning agent after isolating the polyimide [A].

[0172] When the polymer [A] is at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide, the solution viscosity of the polymer [A] is preferably 10 mPa·s to 800 mPa·s, more preferably 15 mPa·s to 500 mPa·s, when prepared as a 10% by mass solution. The solution viscosity (mPa·s) is a value measured at 25°C using an E-type rotational viscometer for a 10% by mass polymer solution prepared in a good solvent for the polymer [A] (e.g., γ-butyrolactone, N-methyl-2-pyrrolidone, etc.).

[0173] The weight average molecular weight (Mw) of the polymer [A] in terms of polystyrene as measured by gel permeation chromatography (GPC) is preferably 1,000 to 500,000, more preferably 2,000 to 300,000. Furthermore, the molecular weight distribution (Mw / Mn), which is represented by the ratio of Mw to the number average molecular weight (Mn) in terms of polystyrene as measured by GPC, is preferably 7 or less, more preferably 5 or less. Furthermore, when preparing the liquid crystal aligning agent, the polymer [A] may be used alone or in combination of two or more.

[0174] <Other ingredients>

[0175] The liquid crystal aligning agent may contain a component different from the polymer [A] (hereinafter also referred to as "other component") as needed, in addition to the polymer [A].

[0176] Polymer [Q]

[0177] The liquid crystal aligning agent of the present disclosure may further contain a polymer not having the partial structure (a) (hereinafter, also referred to as “polymer [Q]”) as a polymer component.

[0178] The main skeleton of polymer [Q] is not particularly limited. As polymer [Q], for example, polyamic acid, polyamic acid ester, polyimide, polyorganosiloxane, polyester, polyenamine (polyenamine), polyurea, polyamide, polyamide-imide, polybenzoxazole precursor, polybenzoxazole, cellulose derivative, polyacetal, (meth) acrylic polymer, styrene polymer, maleimide polymer, styrene-maleimide copolymer, etc. can be listed. From the viewpoint of obtaining a liquid crystal element with high reliability, polymer [Q] is preferably selected from at least one of the group consisting of polyamic acid, polyamic acid ester, polyimide, polyorganosiloxane and addition polymer. As addition polymer, (meth) acrylic polymer, styrene polymer, maleimide polymer and styrene-maleimide copolymer can be listed.

[0179] When the liquid crystal aligning agent of the present disclosure contains both polymer [A] and polymer [Q], the content of polymer [Q] is preferably 1% by mass or more, more preferably 2% by mass or more, relative to the total amount of polymer [A] and polymer [Q]. Furthermore, the content of polymer [Q] is preferably 95% by mass or less, more preferably 90% by mass or less, relative to the total amount of polymer [A] and polymer [Q]. As polymer [Q], one type may be used alone, or two or more types may be used in combination.

[0180] Solvent

[0181] The liquid crystal aligning agent of the present disclosure is preferably prepared as a liquid composition in which a polymer component and other components used as needed are dispersed or dissolved in an appropriate solvent.

[0182] As the solvent, an organic solvent can be preferably used. Specific examples thereof include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, 1,2-dimethyl-2-imidazolidinone, 1,3-dimethyl-2-imidazolidinone, phenol, γ-butyrolactone, γ-butyrolactam, N,N-dimethylformamide, N,N-dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone, diacetone alcohol, 1-hexanol, 2-hexanol, propane-1,2-diol, 3-methoxy-1-butanol, ethylene glycol monomethyl ether, methyl lactate, ethyl lactate, butyl lactate, methyl acetate, ethyl acetate, butyl acetate, and acetoacetic acid. Methyl ester, ethyl acetoacetate, ethyl propionate, 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, isoamyl propionate, isoamyl isobutyrate, diisoamyl ether, ethylene carbonate, propylene carbonate, propylene glycol monomethyl ether (PGME), diethylene glycol diethyl ether acetate, propylene glycol monomethyl ether acetate (PGMEA), propylene glycol diacetate, cyclopentanone, cyclohexanone, etc. As the solvent, one kind may be used alone or two or more kinds may be used in combination.

[0183] Other components contained in the liquid crystal alignment agent include, in addition to those mentioned above, crosslinking agents, antioxidants, metal chelate compounds, curing accelerators, surfactants, fillers, dispersants, photosensitizers, etc. The proportions of other components can be appropriately selected according to the compound within the range that does not impair the effects of the present disclosure.

[0184] The solid content concentration in the liquid crystal alignment agent (the ratio of the total mass of the components other than the solvent of the liquid crystal alignment agent to the total mass of the liquid crystal alignment agent) is appropriately selected in consideration of viscosity, volatility, etc., and is preferably in the range of 1% by mass to 10% by mass. If the solid content concentration is 1% by mass or more, the film thickness of the coating can be fully ensured, and a liquid crystal alignment film showing a better liquid crystal orientation can be obtained, which is preferred in this respect. On the other hand, if the solid content concentration is 10% by mass or less, there is a tendency that the coating can be set to a moderate thickness, and a liquid crystal alignment film showing a good liquid crystal orientation can be easily obtained. In addition, the viscosity of the liquid crystal alignment agent becomes moderate, and the coating property can be made good.

[0185] According to the present disclosure described above, the following liquid crystal alignment agents are provided.

[0186] <1> A liquid crystal aligning agent containing a polymer [A] having the partial structure (a) represented by the above formula (1) in its main chain.

[0187] <2> The liquid crystal aligning agent according to <1>, wherein the polymer [A] contains a structural unit derived from a diamine having the partial structure (a).

[0188] <3> The liquid crystal aligning agent according to <2>, wherein the diamine is a compound represented by the formula (2).

[0189] <4> The liquid crystal aligning agent according to any one of <1> to <3>, wherein the polymer [A] contains a structural unit derived from a tetracarboxylic acid derivative having the partial structure (a).

[0190] <5> The liquid crystal aligning agent according to <4>, wherein the tetracarboxylic acid derivative is at least one selected from the group consisting of the compound represented by the formula (3) and the compound represented by the formula (4).

[0191] <6> The liquid crystal aligning agent according to any one of <1> to <5>, wherein the polymer [A] is at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide.

[0192] <7> The liquid crystal aligning agent according to any one of <1> to <6>, wherein the polymer [A] contains a structural unit derived from an alicyclic tetracarboxylic dianhydride.

[0193] <8> The liquid crystal aligning agent according to any one of <1> to <7>, further comprising a polymer [Q] not having the partial structure (a).

[0194] Liquid crystal alignment film and liquid crystal element

[0195] The liquid crystal alignment film disclosed in the present invention can be manufactured by a liquid crystal alignment agent prepared in the manner described above. In addition, the liquid crystal element disclosed in the present invention includes a liquid crystal alignment film formed using the liquid crystal alignment agent described above. The driving mode of the liquid crystal in the liquid crystal element is not particularly limited. For example, it can be applied to various modes such as TN type, STN type, VA type (including VA-MVA type, VA-patterned vertical alignment (PVA) type, etc.), IPS type, FFS type, optically compensated bend (OCB) type, polymer stabilized alignment (PSA) type, etc. The liquid crystal element can be manufactured, for example, by a method comprising the following steps 1 to 3. The substrate used in step 1 varies depending on the required operation mode. Step 2 and step 3 are common in each operation mode.

[0196] <Step 1: Coating Film Formation>

[0197] First, a liquid crystal alignment agent is applied to a substrate, preferably by heating the applied surface to form a coating film on the substrate. As a substrate, for example, glass such as float glass and soda glass; a transparent substrate containing plastics such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, and poly(alicyclic olefin) can be used. As a transparent conductive film provided on one side of the substrate, a NESA film (a registered trademark of PPG, USA) containing tin oxide (SnO2) or an indium tin oxide (ITO) film containing indium oxide-tin oxide (In2O3-SnO2) can be used. When manufacturing a TN type, STN type, or VA type liquid crystal element, two substrates provided with patterned transparent conductive films are used. On the other hand, when manufacturing an IPS type or FFS type liquid crystal element, a substrate provided with electrodes patterned into a comb shape and an opposing substrate without electrodes are used.

[0198] The method for applying the liquid crystal alignment agent to the substrate is not particularly limited. The liquid crystal alignment agent can be applied to the substrate by, for example, spin coating, printing (for example, offset printing, flexographic printing, etc.), inkjet, slit coating, rod coating, extrusion die, direct gravure coater, chamber doctor coater, offset gravure coater, dip coater, MB coater, etc.

[0199] After applying the liquid crystal alignment agent, it is preferred to perform preheating (prebaking) for the purpose of preventing the applied liquid crystal alignment agent from sagging. The prebaking temperature is preferably 30°C to 200°C, and the prebaking time is preferably 0.25 minutes to 10 minutes. Then, the solvent is completely removed, and a calcination (post-baking) process is performed as needed for the purpose of thermal imidization of the amide structure present in the polymer. The calcination temperature (post-baking temperature) at this time is preferably 80°C to 280°C, more preferably 80°C to 250°C. The post-baking time is preferably 5 minutes to 200 minutes. The thickness of the formed film is preferably 0.001 μm to 1 μm.

[0200] <Step 2: Orientation Treatment>

[0201] In the case of manufacturing TN type, STN type, IPS type or FFS type liquid crystal elements, a process (orientation treatment) of imparting liquid crystal orientation ability to the coating film formed in the process 1 is implemented. Thus, the orientation ability of the liquid crystal molecules is imparted to the coating film to form a liquid crystal alignment film. As an orientation treatment, it is preferred to use a friction treatment in which the surface of the coating film formed on the substrate is wiped with cotton or nylon, or to irradiate the coating film with light to impart a light orientation treatment of liquid crystal orientation ability thereto. In the case of manufacturing a vertically aligned liquid crystal element, the coating film formed in the process 1 can be directly used as a liquid crystal alignment film. In order to further improve the liquid crystal orientation ability, an orientation treatment can also be applied to the coating film.

[0202] Light irradiation for photo-orientation can be performed by the following methods, etc.: a method of irradiating the coating film after the post-baking process; a method of irradiating the coating film after the pre-baking process and before the post-baking process; a method of irradiating the coating film during the heating process of the coating film in at least any one of the pre-baking process and the post-baking process. As radiation irradiated to the coating film, for example, ultraviolet rays and visible light containing light with a wavelength of 150nm to 800nm ​​can be used. Preferably, ultraviolet rays containing light with a wavelength of 200nm to 400nm are used. When the radiation is polarized, it can be linearly polarized or partially polarized. When the radiation used is linearly polarized or partially polarized, the irradiation can be performed from a direction perpendicular to the substrate surface, from an oblique direction, or by combining these directions. The irradiation direction in the case of non-polarized radiation is set to an oblique direction.

[0203] Examples of the light source include low-pressure mercury lamps, high-pressure mercury lamps, deuterium lamps, metal halide lamps, argon resonance lamps, xenon lamps, and excimer lasers. The radiation dose is preferably 200 J / m 2 ~30,000J / m 2 , more preferably 500 J / m 2 ~10,000J / m 2After the light irradiation for imparting alignment ability, the substrate surface may be cleaned using water, an organic solvent (e.g., methanol, isopropyl alcohol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, etc.) or a mixture thereof, or the substrate may be heated.

[0204] <Step 3: Liquid Crystal Cell Construction>

[0205] Prepare two substrates with liquid crystal alignment films formed in the above manner, and manufacture a liquid crystal unit by arranging liquid crystals between the two substrates arranged opposite to each other. When manufacturing a liquid crystal unit, for example, the following methods can be cited: arranging the two substrates opposite to each other with a gap between them in a manner that the liquid crystal alignment films face each other, bonding the peripheral portions of the two substrates with a sealant, injecting liquid crystal into the cell gap surrounded by the substrate surface and the sealant and sealing the injection hole, and a method using a liquid crystal droplet (One Drop Fill, ODF) method. As a sealant, for example, an epoxy resin containing a hardener and aluminum oxide balls as a spacer can be used. As liquid crystals, nematic liquid crystals and smectic liquid crystals can be cited, among which nematic liquid crystals are preferred.

[0206] In the PSA mode, a polymerizable compound (e.g., a multifunctional (meth)acrylate compound) is filled into the cell gap along with liquid crystals. After constructing the liquid crystal cell, the cell is irradiated with light while a voltage is applied between the conductive films on a pair of substrates. When manufacturing a PSA-mode liquid crystal element, the polymerizable compound is used in an amount of 0.01 to 3 parts by mass, preferably 0.1 to 1 part by mass, relative to 100 parts by mass of the liquid crystal.

[0207] When manufacturing a liquid crystal display device, a polarizing plate is then attached to the outer surface of the liquid crystal cell. Examples of polarizing plates include those made by sandwiching a polarizing film called "H film" (polyvinyl alcohol stretched and oriented on one side and iodine absorbed on the other side) between cellulose acetate protective films, or those containing the H film itself.

[0208] The liquid crystal element disclosed herein can be effectively used in a variety of applications. Specifically, it can be used as various display devices or dimming devices, such as watches, portable game consoles, word processors, notebook personal computers, car navigation systems, camcorders, personal digital assistants (PDAs), digital cameras, mobile phones, smartphones, various monitors, liquid crystal televisions, and information displays, as well as retardation films.

[0209] [Example]

[0210] Hereinafter, the embodiment will be described in more detail based on examples, but the present invention is not to be construed as being limited by the following examples.

[0211] In the following examples, the imidization rate of the polyimide in the polymer solution was measured by the following method: The required amounts of the raw material compounds and polymers used in the following examples were ensured by repeating the synthesis on the synthesis scale shown in the following synthesis examples as needed.

[0212] [Imidization ratio of polyimide]

[0213] The polyimide solution was poured into pure water, the resulting precipitate was fully dried under reduced pressure at room temperature, and then dissolved in deuterated dimethyl sulfoxide. Tetramethylsilane was used as a reference substance and the reaction was carried out at room temperature. 1 H-NMR (Nuclear Magnetic Resonance, NMR) determination. 1 The imidization ratio [%] was determined from the H-NMR spectrum using the following formula (1).

[0214] Imidization rate [%] = (1-(A 1 / (A 2 ×α)))×100···(1)

[0215] (In equation (1), A 1 A is the peak area of ​​protons originating from NH groups appearing near the chemical shift of 10 ppm. 2 is the peak area derived from other protons, and α is the ratio of the number of other protons to one proton of the NH group in the polymer precursor (polyamic acid)

[0216] The abbreviations of the compounds are as follows: In the following, the compound represented by formula (X) may be simply referred to as "compound (X)".

[0217] (Tetracarboxylic dianhydride)

[0218] [Chemistry 26]

[0219]

[0220] [Chemistry 27]

[0221]

[0222] (Diamine compound)

[0223] [Chemistry 28]

[0224]

[0225] [Chemistry 29]

[0226]

[0227] [Chemistry 30]

[0228]

[0229] [Chemistry 31]

[0230]

[0231] [Chemistry 32]

[0232]

[0233] (Other compounds)

[0234] [Chemistry 33]

[0235]

[0236] [Chemistry 34]

[0237]

[0238] <Synthesis of Monomer>

[0239] 1. Synthesis of Compound (DA-1), Compound (DA-8), and Compound (DA-9)

[0240] Compound (DA-1), Compound (DA-8), and Compound (DA-9) were synthesized by a method similar to the method described in Japanese Patent No. 6013823. The production formula of Compound (DA-1) is shown below.

[0241] Synthesis of compound (DA-1)

[0242] 30 g (0.2 mol) of 4-(2-methylamino-ethyl)-phenylamine and 200 ml of tetrahydrofuran were added to a reaction vessel. A solution of 20 g (0.2 mol) of maleic anhydride dissolved in 30 ml of tetrahydrofuran was added dropwise under ice cooling, and the mixture was stirred at room temperature overnight. After the reaction, the precipitated solid was filtered, washed three times with 20 ml of tetrahydrofuran, and dried at 60°C for 3 hours to obtain a brown solid. Next, 30 g (0.2 mol) of 4-(2-methylamino-ethyl)-phenylamine, 0.5 g of dimethylaminopyridine, and 100 ml of dimethylformamide were added to the reaction vessel containing the resulting solid. 38 g (0.2 mol) of 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride was added under ice cooling, and the mixture was stirred at room temperature overnight. After the reaction, 300 ml of water was added, and the mixture was extracted three times with 300 ml of ethyl acetate. After drying with sodium sulfate, the solvent was distilled off to obtain 28 g of a brown viscous solid. 80 ml of methanol was added to the obtained solid, and the insoluble solid was filtered out to obtain 20 g of compound (DA-1) as a brown solid. 1 The results of H-NMR measurement are as follows.

[0243] 1 H-NMR (300 MHz, DMSO-d 6 )δppm:7.02(4H,d),6.53(4H,d),6.44(2H,s),3.22-3.57(10H,m),2.62(4H,t).

[0244] 2. Synthesis of compound (DA-2) ~ compound (DA-7)

[0245] Compounds (DA-2) to (DA-7) were first prepared by referring to the method described in the reference document (Journal of Polymer Science: Polymer Chemistry Edition, 1975, Vol. 13, 1691-1698) to produce compounds (D-1) to (D-4). Compounds (D-1) to (D-4) were then prepared by a synthetic method using the resulting compounds as intermediates. The production formula for compound (DA-2) is shown below. Compounds (DA-2) to (DA-7) are cis-isomers.

[0246] Synthesis of compound (DA-2)

[0247] 19.6 g (0.2 mol) of maleic anhydride and 100 ml of acetic acid were added to the reaction vessel. A solution obtained by dissolving 5.0 g (0.1 mol) of hydrazine monohydrate in 25 ml of acetic acid was added dropwise thereto. During the addition, the reaction temperature was controlled using an ice bath so that the reaction solution would not reach above 25°C. After the addition was completed, the mixture was allowed to stand for 3 hours, the precipitate was filtered out, and the mixture was washed three times with 30 ml of ethanol. Then, the mixture was dried at 60°C for 5 hours to obtain 21 g of a light yellow solid. The obtained solid was transferred to a reaction vessel, 110 ml of thionyl chloride was added, and the mixture was stirred at 75°C for 6 hours. After the reaction, the mixture was cooled to room temperature and the precipitate was filtered out. The precipitate was washed with hexane and dried at 60°C for 5 hours to obtain 10 g (0.05 mol) of compound (D-1). The obtained compound (D-1) was dissolved in 50 ml of N-methyl-2-pyrrolidone, and 14 g (0.1 mol) of 2-(4-aminophenyl)ethylamine was added dropwise over 30 minutes. After the addition, the mixture was stirred at room temperature for 1 hour, and the reaction solution was added to 500 ml of water to obtain a precipitate. The obtained precipitate was filtered, washed with water, and dried at 60°C for 5 hours to obtain 20 g of compound (DA-2). 1 The results of H-NMR measurement are as follows.

[0248] 1 H-NMR (300 MHz, DMSO-d 6 )δppm:8.96(2H,s),6.89(4H,m),6.51(4H,m),6.19-6.31(4H,m),3.29(4H,m),2.60(4H,m).

[0249] 3. Synthesis of compound (DA-10)

[0250] 13.9 g (0.1 mol) of 2-amino-5-nitropyridine, 7.9 g (0.1 mol) of pyridine and 50 ml of tetrahydrofuran were added to the reaction vessel. A solution obtained by dissolving 7.6 g (0.05 mol) of fumaryl chloride in 25 ml of tetrahydrofuran was added dropwise thereto. After the addition was completed, the mixture was stirred at room temperature for 8 hours. The resulting reaction solution was poured into water and the precipitate was filtered out. The solid obtained was washed with water and ethanol and dried at 60°C for 5 hours to obtain 14.5 g of the intermediate as a brown solid. The intermediate obtained was transferred to a reaction vessel, 10 wt% palladium / carbon (2 g) and N,N-dimethylformamide (30 ml) were added, and the mixture was heated at 50°C for 8 hours under a hydrogen atmosphere. After filtering the reaction solution and removing the catalyst, the filtrate was poured into ice water, and the generated precipitate was filtered and recovered. The obtained solid was washed with ethanol and dried at 60°C for 5 hours to obtain 12.2 g of compound (DA-10). 1 The results of H-NMR measurement are as follows.

[0251] 1 H-NMR (300 MHz, DMSO-d 6 )δppm:11.2(2H,s),7.13-7.44(6H,m),6.18(2H,s).

[0252] 4. Synthesis of compound (DA-12)

[0253] Compound (DA-12) was synthesized by the same method as that for Compound (DA-10), except that 4-nitroaniline was used as a raw material instead of 2-amino-5-nitropyridine.

[0254] 5. Synthesis of compound (DA-11)

[0255] 13.9 g (0.1 mol) of 2-amino-5-nitropyridine, 7.9 g (0.1 mol) of pyridine, and 50 ml of tetrahydrofuran were added to a reaction vessel. A solution of 7.6 g (0.05 mol) of fumaryl chloride dissolved in 25 ml of tetrahydrofuran was added dropwise. After the addition was complete, the mixture was stirred at room temperature for 8 hours. The resulting reaction solution was poured into water, and the precipitate was filtered out. The resulting solid was washed with water and ethanol, and dried at 60°C for 5 hours to obtain 14.5 g of the intermediate as a brown solid. The resulting intermediate was transferred to a reaction vessel, and 25 ml of dimethylformamide was added. 18 g (0.08 mmol) of di-tert-butyl dicarbonate was added thereto, and the mixture was stirred at room temperature for 16 hours. The reaction solution was added dropwise to water, and the precipitate was filtered out. After washing with water, the precipitate was dried at 60°C for 3 hours to obtain 13.2 g of a light brown solid. The obtained solid was transferred to a reaction vessel, 10 wt% palladium / carbon (1.8 g) and N,N-dimethylformamide (30 ml) were added, and heated at 50°C for 8 hours under a hydrogen atmosphere. After filtering the reaction solution and removing the catalyst, the filtrate was poured into ice water, and the generated precipitate was filtered and recovered. The obtained solid was washed with ethanol and dried at 60°C for 5 hours to obtain 9.8 g of compound (DA-11). 1 The results of H-NMR measurement are as follows.

[0256] 1 H-NMR (300 MHz, DMSO-d 6 )δppm:8.09(2H,m),7.28-7.44(4H,m),6.93(2H,s),1.39(18H,s).

[0257] 6. Synthesis of compound (DA-13)

[0258] Compound (DA-13) was synthesized by the same method as that of (DA-11) except that 4-nitroaniline was used as a raw material instead of 2-amino-5-nitropyridine.

[0259] 7. Synthesis of Compound (TA-1)

[0260] 11.5 g (0.1 mol) of 3-aminodihydrofuran-2,5-dione, 7.9 g (0.1 mol) of pyridine, and 300 ml of tetrahydrofuran were added to the reaction vessel. The reaction solution was brought to 0°C using an ice bath, and a solution of 7.6 g (0.05 mol) of fumaryl chloride dissolved in 50 ml of tetrahydrofuran was added dropwise thereto. After the addition was completed, the mixture was stirred at room temperature for 4 hours. After the reaction, the solvent was removed under reduced pressure. Subsequently, 50 g of acetic acid and 50 g of acetic anhydride were added, and the mixture was stirred at 100°C for 3 hours. The obtained precipitate was filtered, washed with acetic acid and n-hexane, and then dried under reduced pressure at 60°C for 5 hours to obtain compound (TA-1).

[0261] 8. Synthesis of compound (TA-2)

[0262] Compound (TA-2) was synthesized by the same method as that of compound (TA-1) except that 5-hydroxyisobenzofuran-1,3-dione was used as a raw material instead of 3-aminodihydrofuran-2,5-dione.

[0263] 9. Synthesis of compound (TA-3)

[0264] 19.6 g (0.2 mol) of maleic anhydride and 100 ml of acetic acid were added to the reaction vessel. A solution obtained by dissolving 5.0 g (0.1 mol) of hydrazine monohydrate in 25 ml of acetic acid was added dropwise thereto. During the addition, the reaction temperature was controlled using an ice bath so that the reaction solution would not reach above 25°C. After the addition was completed, the mixture was allowed to stand for 3 hours, the precipitate was filtered out, and the mixture was washed three times with 30 ml of ethanol. Then, the mixture was dried at 60°C for 5 hours to obtain 21 g of a light yellow solid. The obtained solid was transferred to a reaction vessel, 110 ml of thionyl chloride was added, and the mixture was stirred at 75°C for 6 hours. After the reaction, the mixture was cooled to room temperature and the precipitate was filtered out. The precipitate was washed with hexane and dried at 60°C for 5 hours to obtain 10 g (0.05 mol) of compound (D-1). The obtained compound (D-1) was dissolved in 50 ml of N-methyl-2-pyrrolidone, and 11.5 g (0.1 mol) of 3-aminodihydrofuran-2,5-dione was added dropwise over 30 minutes. After the addition was completed, the mixture was stirred at room temperature for 4 hours. After the reaction, the solvent was removed under reduced pressure. Then, 50 g of acetic acid and 50 g of acetic anhydride were added and stirred at 100 ° C for 3 hours. The obtained precipitate was filtered, washed with acetic acid and n-hexane, and dried under reduced pressure at 60 ° C for 5 hours to obtain compound (TA-3). Furthermore, compound (TA-3) is a cis isomer.

[0265] <Polymer Synthesis>

[0266] 1. Synthesis of polyamic acid

[0267] [Synthesis example 1]

[0268] 100 parts by mole of 1,2,3,4-cyclobutanetetracarboxylic dianhydride (compound (TB-1)) as a tetracarboxylic dianhydride and 100 parts by mole of compound (DA-2) as a diamine compound were dissolved in N-methyl-2-pyrrolidone (NMP), and the mixture was reacted at room temperature for 6 hours to obtain a solution containing 15% by mass of a polyamic acid (referred to as polymer (PAA-1)).

[0269] Furthermore, polymer (PAA-1) can also be obtained by polymerizing compound (D-1) as an intermediate instead of isolated compound (DA-2). Different synthesis methods of polymer (PAA-1) are shown below.

[0270] [Alternative Synthesis Method of PAA-1]

[0271] 100 parts by mole of compound (D-1) was dissolved in N-methyl-2-pyrrolidone, and 200 parts by mole of 2-(4-aminophenyl)ethylamine was added dropwise over 30 minutes. After the addition, the mixture was stirred at room temperature for 1 hour. Then, 100 parts by mole of 1,2,3,4-cyclobutanetetracarboxylic dianhydride was added as a tetracarboxylic dianhydride, and the mixture was reacted at room temperature for 6 hours to obtain a solution containing 15% by mass of polymer (PAA-1).

[0272] [Synthesis Example 2 to Synthesis Example 24]

[0273] Polyamic acids (polymers (PAA-2) to (PAA-20) and polymers (paa-1) to (paa-4)) were obtained by the same operation as in Synthesis Example 1, except that the types and amounts of the tetracarboxylic dianhydride and diamine compound used were changed as described in Table 1. In Table 1, the numerical values ​​for tetracarboxylic dianhydride (acid dianhydride 1 and acid dianhydride 2) represent the ratio (molar ratio) of each compound relative to 100 parts by mole of the total amount of tetracarboxylic dianhydride used in the synthesis of the polyamic acid. The numerical values ​​for diamine compounds (diamine 1 to diamine 3) represent the ratio (molar ratio) of each compound relative to 100 parts by mole of the total amount of diamine compounds used in the synthesis of the polyamic acid.

[0274] [Table 1]

[0275]

[0276] 2. Synthesis of polyimide

[0277] [Synthesis Example 25]

[0278] 60 parts by mole of compound (TB-1) and 40 parts by mole of compound (TB-3) as tetracarboxylic dianhydride, 20 parts by mole of compound (DA-2) as diamine compound, 60 parts by mole of compound (DB-2) and 20 parts by mole of compound (DB-3) were dissolved in NMP and reacted at room temperature for 6 hours to obtain a solution containing 15% by mass of polyamic acid. Subsequently, NMP was added to the obtained polyamic acid solution to prepare a solution having a polyamic acid concentration of 10% by mass, pyridine and acetic anhydride were added, and a dehydration ring-closure reaction was carried out at 60°C for 4 hours. After the dehydration ring-closure reaction, the solvent in the system was replaced with new NMP to obtain a solution containing 15% by mass of a polyimide (referred to as polymer (PI-1)) having an imidization rate of approximately 80%.

[0279] [Synthesis Example 26 to Synthesis Example 30]

[0280] The same operation as in Synthesis Example 25 was performed except that the types and amounts of the tetracarboxylic dianhydride and diamine compound used were changed as described in Table 2, thereby obtaining polyimides (polymers (PI-2) to (PI-3) and polymers (PI-1) to (PI-3)). In Table 2, the numerical values ​​of the tetracarboxylic dianhydride (acid dianhydride 1 to acid dianhydride 3) represent the ratio (molar ratio) of each compound relative to 100 parts by mole of the total amount of the tetracarboxylic dianhydride used in the synthesis of the polyimide. The numerical values ​​of the diamine compounds (diamine 1 to diamine 4) represent the ratio (molar ratio) of each compound relative to 100 parts by mole of the total amount of the diamine compounds used in the synthesis of the polyimide.

[0281] [Table 2]

[0282]

[0283] 3. Synthesis of polyorganosiloxane

[0284] [Synthesis Example 31]

[0285] 100.0 g of 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane (compound (s-1)), 500 g of methyl isobutyl ketone, and 10.0 g of triethylamine were placed in a 1000 ml three-necked flask and mixed at room temperature. Subsequently, 100 g of deionized water was added dropwise from a dropping funnel over 30 minutes, followed by mixing under reflux and reacting at 80°C for 6 hours. After the reaction was completed, the organic layer was removed and washed with a 0.2% by mass aqueous solution of ammonium nitrate until the washed water became neutral. The solvent and water were then distilled off under reduced pressure. An appropriate amount of methyl isobutyl ketone was added to obtain a 50% by mass solution of a polymer (ESSQ-1), a polyorganosiloxane having an epoxy group.

[0286] To a 500 ml three-necked flask were added 3.10 g of compound (c-1) (20 mol% relative to the amount of epoxy groups in polymer (ESSQ-1)), 3.24 g of compound (c-2) (10 mol% relative to the amount of epoxy groups in polymer (ESSQ-1)), 1.00 g of tetrabutylammonium bromide, 20.0 g of a solution containing polymer (ESSQ-1), and 290.0 g of methyl isobutyl ketone, and the mixture was stirred at 90° C. for 18 hours. After cooling to room temperature, liquid separation and washing with distilled water were repeated 10 times. The organic layer was then recovered, concentrated using a rotary evaporator, and diluted with NMP twice. The solids concentration was then adjusted using NMP to 10% by mass, thereby obtaining an NMP solution of polyorganosiloxane (referred to as polymer (PSQ-1)).

[0287] 4. Synthesis of Styrene-Maleimide Copolymers

[0288] [Synthesis Example 32]

[0289] Under nitrogen, a 100 mL two-necked flask was charged with 5.00 g of compound (M-1), 1.05 g of compound (M-2), 4.80 g of compound (M-3), and 2.26 g of compound (M-4) as polymerization monomers; 0.39 g of 2,2'-azobis(2,4-dimethylvaleronitrile) as a radical polymerization initiator; 0.39 g of 2,4-diphenyl-4-methyl-1-pentene as a chain transfer agent; and 52.5 ml of N-methyl-2-pyrrolidone (NMP) as a solvent. Polymerization was carried out at 70°C for 6 hours. After reprecipitation in methanol, the precipitate was filtered and vacuum-dried at room temperature for 8 hours to obtain the target polymer (referred to as polymer (MI-1)).

[0290] 5. Synthesis of polyamide

[0291] [Synthesis Example 33]

[0292] The synthesis was carried out according to the method described in the reference document (Journal of Polymer Science: Polymer Chemistry Edition, 1975, Vol. 13, 1691-1698). 100 parts by mole of compound (D-1), a bisisomaleimide, and 100 parts by mole of compound (DB-18), a diamine compound, were dissolved in N-methyl-2-pyrrolidone (NMP) and reacted at room temperature for 6 hours to obtain a solution containing 15% by mass of a polyamide (referred to as polymer (pa-1)).

[0293] <Evaluation as a polymer>

[0294] [Example 1: Evaluation of Residual Amine and Storage Stability]

[0295] 1. Evaluation of residual amines

[0296] A solution of the polymer (PAA-1) obtained in Synthesis Example 1 was added dropwise to acetone to precipitate the polymer. A portion of the supernatant was removed and evaluated by liquid chromatography (LC). If a peak corresponding to the diamine used as a raw material was observed, the peak was recorded as "present"; if not, the peak was recorded as "absent." The results showed that the peak for residual amine in Example 1 was "absent."

[0297] 2. Evaluation of storage stability

[0298] The storage stability of the polymer (PAA-1) solution obtained in Synthesis Example 1 was evaluated based on the ratio of change between the viscosity D1 of the polymer solution immediately after preparation and the viscosity D2 of the polymer solution after storage at room temperature for 7 days ([(D2-D1) / D1)]×100(%)). A viscosity change of 5% or greater was evaluated as "poor (×)," while a viscosity change of less than 5% was evaluated as "good (○)." The storage stability of Example 1 was rated "good (○)."

[0299] [Reference Example 1]

[0300] The residual amine and storage stability were evaluated in the same manner as in Example 1 except that the polymer was changed as shown in Table 3. The results are shown in Table 3.

[0301] [Table 3]

[0302] Polymer type Residual amines Storage stability Example 1 PAA-1 none ○ Reference Example 1 pa-1 have ×

[0303] As shown in Table 3, the polymer (PAA-1) had less residual amine than the polymer (pa-1) which was a polyamide, and also had good storage stability as a solution.

[0304] <Preparation and Evaluation of Liquid Crystal Alignment Agents>

[0305] [Example 2: Rubbing FFS Type Liquid Crystal Display Element]

[0306] 1. Preparation of liquid crystal alignment agent

[0307] The polymer (PAA-2) solution obtained in Synthesis Example 2 was diluted with NMP and butyl cellosolve (BC) to prepare a solution having a solvent composition of NMP / BC = 80 / 20 (mass ratio) and a solids concentration of 3.5% by mass. This solution was filtered through a filter with a pore size of 0.2 μm to prepare a liquid crystal aligning agent (AL-1).

[0308] 2. Manufacturing of FFS-type liquid crystal display elements using the rubbing method

[0309] Prepare a glass substrate (set as the first substrate) on which a flat electrode (bottom electrode), an insulating layer and a comb-shaped electrode (top electrode) are sequentially stacked on a single surface, and a glass substrate (set as the second substrate) on which no electrode is set. Subsequently, a liquid crystal alignment agent (AL-1) is applied to the electrode forming surface of the first substrate and a single surface of the second substrate using a spinner, and heated (pre-baked) for 3 minutes using a hot plate at 110°C. Then, it is dried (post-baked) for 30 minutes in an oven at 230°C in which nitrogen is substituted in the reservoir to form a coating with an average film thickness of 0.08 μm. Subsequently, a friction machine having a roller wound with rayon cloth is used to rub the surface of the coating at a roller speed of 1000 rpm, a stage moving speed of 3 cm / second, and a hair pressing length of 0.3 mm. Then, ultrasonic cleaning is performed in ultrapure water for 1 minute, followed by drying in a clean oven at 100°C for 10 minutes to obtain a pair of substrates having a liquid crystal alignment film.

[0310] Then, for a pair of substrates having a liquid crystal alignment film, a liquid crystal injection port is left at the edge of the surface on which the liquid crystal alignment film is formed, and an epoxy resin adhesive filled with alumina balls with a diameter of 3.5 μm is screen-printed and coated. Then, the substrates are overlapped and pressed, and the adhesive is thermally cured at 150°C for 1 hour. Then, after filling the gap between a pair of substrates with a negative liquid crystal (manufactured by Merck, MLC-6608) from the liquid crystal injection port, the liquid crystal injection port is sealed with an epoxy adhesive. Furthermore, in order to remove the flow orientation during liquid crystal injection, it is heated at 120°C and then slowly cooled to room temperature to manufacture a liquid crystal unit. Furthermore, when a pair of substrates are overlapped, the friction method of each substrate becomes antiparallel.

[0311] 3. Evaluation of liquid crystal orientation

[0312] The liquid crystal cell manufactured in 2. was set at 27,000 cd / m 2The liquid crystal orientation is evaluated by standing on a high-brightness backlight for 500 hours, and the rate of change of delay before and after backlight irradiation is used to evaluate the liquid crystal orientation. First, for the liquid crystal display element manufactured in 2., the delay is measured using Axoscan manufactured by Opto Science, and the rate of change of delay before and after backlight irradiation α is calculated using the following formula (z-1). It can be said that the smaller the rate of change α, the better the liquid crystal orientation. The case where the rate of change α is less than 1% is set to "good (○)", the case where it is greater than 1% and less than 2% is set to "acceptable (△)", and the case where it is greater than 2% is set to "poor (×)".

[0313] α=Δθ / θ1···(z-1)

[0314] (In formula (z-1), Δθ represents the retardation difference before and after irradiation, and θ1 represents the retardation value before irradiation)

[0315] As a result, the evaluation of the liquid crystal orientation of the said Example was "good (◯)".

[0316] 4. Initial VHR Assessment

[0317] The liquid crystal cell produced in step 2 was placed in a 60°C oven and then measured for voltage holding ratio (VHR) at 1 V and 1670 msec using a VHR measuring device "VHR-1" manufactured by ToyoTechnica. As an evaluation standard, a VHR exceeding 70% was rated "good (○)", a VHR between 70% and 60% was rated "acceptable (△)", and a VHR below 60% was rated "poor (×)". The initial VHR of this example was rated "good (○)".

[0318] 5. Evaluation of VHR reliability

[0319] For the liquid crystal unit manufactured in 2. above, the reliability (VHR reliability) is evaluated by the voltage holding ratio. The evaluation is performed as follows. First, after applying a voltage of 1V for 60 microseconds to the liquid crystal unit, the voltage holding ratio (VHR1) is measured 1670 milliseconds after the application is released. Then, after irradiating the liquid crystal unit with a cold cathode fluorescent lamp (CCFL) (backlight) at 60°C for one week, it is left to stand at room temperature and naturally cool to room temperature. After cooling, after applying a voltage of 1V for 60 microseconds to the liquid crystal unit, the voltage holding ratio (VHR2) is measured 1670 milliseconds after the application is released. In addition, the measuring device is a VHR measuring device "VHR-1" manufactured by Toyo Technica. The rate of change of VHR at this time (ΔVHR) is calculated based on the difference between VHR1 and VHR2 (ΔVHR=VHR1-VHR2), and the VHR reliability is evaluated based on ΔVHR. A ΔVHR of less than 15% was evaluated as "good (○)", a ΔVHR of 15% or more and 20% or less was evaluated as "acceptable (△)", and a ΔVHR of more than 20% was evaluated as "poor (×)". The results showed that the VHR reliability in the above example was "good (○)".

[0320] 6. Evaluation of film strength (friction resistance)

[0321] The liquid crystal alignment agent (AL-1) prepared in 1. is applied to a glass substrate using a rotator and heated (pre-baked) on a hot plate at 110°C for 3 minutes. Then, it is dried (post-baked) for 30 minutes in an oven at 230°C in which nitrogen is substituted in the reservoir to form a coating having an average film thickness of 0.08 μm. For the coating, the haze value of the coating is measured using a haze meter. Subsequently, a friction machine having a roller wound with cotton cloth is used to perform 5 friction treatments on the coating at a roller speed of 1000 rpm, a stage moving speed of 3 cm / second, and a hair indentation length of 0.3 mm. Then, the haze value of the liquid crystal alignment film is measured using a haze meter, and the difference (haze change value) from the haze value before the friction treatment is calculated. When the haze value of the film before the friction treatment is set to Hz1 (%) and the haze value of the film after the friction treatment is set to Hz2 (%), the haze change value is expressed by the following formula (z-2).

[0322] Haze change (%) = Hz2 - Hz1···(z-2)

[0323] The case where the haze change value of the liquid crystal alignment film is less than 0.5 is evaluated as "optimal (◎)", the case where the haze change value is greater than 0.5 and less than 1.0 is evaluated as "good (○)", the case where the haze change value is greater than 1.0 and less than 1.5 is evaluated as "acceptable (△)", and the case where the haze change value is greater than 1.5 is evaluated as "poor (×)". If the haze change value is less than 1.5 (more preferably less than 1.0, and more preferably less than 0.5), it can be said that the film strength is sufficiently high and the friction resistance is high, that is, the mechanical properties of the film are good. As a result, the film strength is evaluated as "good (○)" in the above embodiment.

[0324] 7. Evaluation of membrane strength (keystroke resistance test)

[0325] The keystroke resistance of the liquid crystal unit manufactured in 2. was evaluated. The evaluation was carried out as follows. First, the liquid crystal unit was observed under crossed Nicols of a polarizing microscope, and the number of bright spots was counted. Secondly, the liquid crystal unit was fixed on a fixed plate, and the load was repeatedly applied to the liquid crystal unit by moving the key rod up and down. The load at this time was set to 250 gf, the number of repetitions was set to 100,000 times, and the speed was set to 10 Hz / sec. After pressing the key, the liquid crystal unit was observed again, and the number of bright spots was counted. When the difference in the number of bright spots before and after the keystroke was less than 5, it was evaluated as "optimal (◎)", when it was more than 5 and less than 10, it was evaluated as "good (○)", when it was more than 10 and less than 50, it was evaluated as "acceptable (△)", and when it was more than 50, it was evaluated as "unacceptable (×)". If the difference in the number of bright spots was less than 10 (more preferably less than 5), it can be said that the membrane has good mechanical strength for the keystroke. As a result, the membrane strength was evaluated as "good (○)" in the embodiment.

[0326] [Examples 2 to 15 and Comparative Examples 2 and 3]

[0327] The liquid crystal alignment agent was prepared in the same manner as in Example 2 except that the composition of the liquid crystal alignment agent was changed as shown in Table 4. In addition, the obtained liquid crystal alignment agent was used to manufacture an FFS type liquid crystal unit by a friction method in the same manner as in Example 2, and various evaluations were performed. These results are shown in Table 4. Furthermore, in Example 3, Example 4, Example 7 and Examples 12 to 15, two polymers were used as polymer components. In Table 4, the numerical values ​​in the polymer column represent the blending ratio (parts by mass) of each polymer in terms of solid content relative to 100 parts by mass of the total amount of the polymer components used in the preparation of the liquid crystal alignment agent.

[0328] [Table 4]

[0329]

[0330] As shown in Table 4, Examples 2 to 15 using liquid crystal alignment agents containing polymer [A] achieved excellent or optimal results in terms of film strength, particularly keystroke resistance, compared to Comparative Examples 2 and 3 using liquid crystal alignment agents not containing polymer [A]. Furthermore, Examples 2 to 15 also achieved excellent liquid crystal alignment, initial VHR, and VHR reliability.

[0331] [Example 16: Light FFS Type Liquid Crystal Display Element]

[0332] 1. Preparation of liquid crystal alignment agent

[0333] A solution containing 30 parts by mass of the polymer (PAA-15) obtained in Synthesis Example 15 and a solution containing 70 parts by mass of the polymer (PAA-2) obtained in Synthesis Example 18 were mixed and diluted with NMP and BC to prepare a solution having a solvent composition of NMP / BC = 80 / 20 (mass ratio) and a solid content concentration of 3.5% by mass. The solution was filtered through a filter with a pore size of 0.2 μm to prepare a liquid crystal aligning agent (AL-17).

[0334] 2. Manufacturing of FFS-type liquid crystal display elements using the photo-alignment method

[0335] Prepare the same first substrate and second substrate as in Example 1. Then, use a spinner to apply the liquid crystal alignment agent (AL-17) to the electrode forming surface of the first substrate and one of the substrate surfaces of the second substrate, respectively, and heat (pre-bake) on an 80°C hot plate for 1 minute. Then, dry (post-bake) in a 230°C oven in which nitrogen is substituted for the interior of the chamber for 30 minutes to form a coating with an average film thickness of 0.1 μm. Use a Hg-Xe lamp to irradiate the resulting coating with 1,000 J / m of ultraviolet light containing a linearly polarized 254 nm bright line from the normal direction of the substrate. 2 The photo-alignment treatment was performed. The irradiation dose was measured using a light meter with a wavelength of 254 nm. The photo-alignment treated coating was then heated in a clean oven at 230° C. for 30 minutes to form a liquid crystal alignment film.

[0336] Secondly, for one of the pair of substrates on which a liquid crystal alignment film is formed, an epoxy resin adhesive filled with aluminum oxide balls with a diameter of 3.5 μm is applied to the outer edge of the surface with the liquid crystal alignment film by screen printing. Then, the substrates are overlapped and pressed in such a way that the projection direction of the polarization axis on the substrate surface becomes antiparallel during light irradiation, and the adhesive is thermally cured at 150°C for 1 hour. Subsequently, a negative liquid crystal (manufactured by Merck, MLC-6608) is filled between a pair of substrates from the liquid crystal injection port, and the liquid crystal injection port is sealed with an epoxy adhesive to obtain a liquid crystal unit. Furthermore, in order to remove the flow orientation during liquid crystal injection, it is heated at 120°C and then slowly cooled to room temperature. In addition, by respectively adjusting the ultraviolet irradiation amount after post-baking to 100 J / m 2 ~10,000J / m 2 The series of operations are performed by making changes within a range to manufacture three or more liquid crystal units with different ultraviolet irradiation amounts, and the liquid crystal unit with the exposure amount (optimal exposure amount) showing the best orientation characteristics is used for the following evaluation of liquid crystal orientation, initial VHR, VHR reliability and film strength.

[0337] 3. Evaluation

[0338] The liquid crystal cell produced in 2. was evaluated for liquid crystal orientation, initial VHR, and VHR reliability by the same methods as in Example 2. Furthermore, using the liquid crystal aligning agent (AL-17), film strength was evaluated in the same manner as in Example 2. The evaluation results are shown in Table 5.

[0339] [Examples 17 to 23, Comparative Examples 4 and 5]

[0340] Except that the composition of the liquid crystal alignment agent is changed as shown in Table 5, the liquid crystal alignment agent is prepared in the same manner as in Example 16. In addition, using the obtained liquid crystal alignment agent, an FFS type liquid crystal unit is manufactured by a photo-orientation method in the same manner as in Example 16, and various evaluations are performed. The results of these are shown in Table 5. Furthermore, in Example 23 and Comparative Example 5, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane (set to compound (N-1)) is formulated as an additive component together with the polymer component. In Table 5, the numerical value in the polymer column represents the formulation ratio (mass parts) of each polymer in terms of solid content relative to 100 parts by mass of the total amount of solid components (polymer components and additive components) used in the preparation of the liquid crystal alignment agent.

[0341] [Table 5]

[0342]

[0343] As shown in Table 5, Examples 16 to 23 using a liquid crystal alignment agent containing polymer [A] show good or optimal results in terms of film strength, especially resistance to keystroke testing, compared with Comparative Examples 4 and 5 using a liquid crystal alignment agent not containing polymer [A], achieving balanced performance in liquid crystal orientation, initial VHR, and VHR reliability.

[0344] [Example 24: PSA-type liquid crystal display element]

[0345] 1. Preparation of liquid crystal alignment agent

[0346] A solution containing 5 parts by mass of the polymer (PSQ-1) obtained in Synthesis Example 31 and a solution containing 95 parts by mass of the polymer (PI-3) obtained in Synthesis Example 27 were mixed and diluted with NMP and BC to prepare a solution having a solvent composition of NMP / BC = 50 / 50 (mass ratio) and a solid content concentration of 3.5% by mass. The solution was filtered through a filter with a pore size of 0.2 μm to prepare a liquid crystal aligning agent (AL-27).

[0347] 2. Preparation of Liquid Crystal Composition

[0348] To 10 g of nematic liquid crystal (MLC-6608, manufactured by Merck), 5% by mass of a liquid crystal compound represented by the following formula (L1-1) and 0.3% by mass of a photopolymerizable compound represented by the following formula (L2-1) were added and mixed to obtain a liquid crystal composition LC1.

[0349] [Chemistry 35]

[0350]

[0351] 3. Manufacturing of PSA-type liquid crystal display elements

[0352] The prepared liquid crystal alignment agent (AL-27) is applied to the transparent electrode surface of a glass substrate with a transparent electrode containing an ITO film using a spinner, and after pre-baking on a hot plate at 80°C for 1 minute, the solvent is removed by heating at 200°C in an oven replaced with nitrogen for 1 hour to form a coating film (liquid crystal alignment film) with a film thickness of 0.08 μm. The coating film is rubbed using a friction machine having a roller wound with rayon cloth at a roller speed of 400 rpm, a stage moving speed of 3 cm / second, and a hair press length of 0.1 mm. Then, ultrasonic cleaning is performed in ultrapure water for 1 minute, followed by drying in a clean oven at 100°C for 10 minutes to obtain a substrate with a liquid crystal alignment film. The operation is repeated to obtain a pair (two) of substrates with a liquid crystal alignment film. Furthermore, the rubbing treatment is a weak rubbing treatment performed for the purpose of controlling the collapse of the liquid crystal and performing orientation segmentation using a simple method.

[0353] An epoxy resin adhesive loaded with 3.5μm-diameter alumina spheres was screen-printed onto the periphery of the surface of one of the substrates having the liquid crystal alignment film. The pair of substrates were then placed with their liquid crystal alignment film surfaces facing each other, overlapped, and pressure-bonded. The adhesive was then cured by heating at 150°C for one hour. Subsequently, the gap between the substrates was filled with liquid crystal composition LC1 through the liquid crystal injection port. The liquid crystal injection port was then sealed with an epoxy adhesive. Furthermore, to eliminate flow alignment during liquid crystal injection, the mixture was heated at 150°C for 10 minutes and then slowly cooled to room temperature.

[0354] Then, an alternating current of 10 V at a frequency of 60 Hz was applied between the electrodes of the obtained liquid crystal cell, and while the liquid crystal was being driven, an ultraviolet irradiation device using a metal halide lamp as a light source was used at a radiation intensity of 50,000 J / m 2 The ultraviolet rays were irradiated at an irradiation dose of 100 nm. The irradiation dose was a value measured using a light meter with a wavelength of 365 nm as a reference. Thus, a PSA liquid crystal cell was manufactured.

[0355] 4. Evaluation

[0356] The liquid crystal cell produced in 3. above was evaluated for liquid crystal orientation, initial VHR, VHR reliability, and film strength by the same method as in Example 2. The evaluation results are shown in Table 6.

[0357] [Comparative Example 6]

[0358] A liquid crystal alignment agent was prepared in the same manner as in Example 24, except that the composition of the liquid crystal alignment agent was changed as shown in Table 6. Furthermore, a PSA-type liquid crystal cell was produced in the same manner as in Example 24 using the resulting liquid crystal alignment agent, and various evaluations were performed. The evaluation results are shown in Table 7. In Table 7, the values ​​in the polymer column represent the blending ratio (parts by mass) of each polymer in terms of solid content relative to 100 parts by mass of the total amount of the polymer components used in the preparation of the liquid crystal alignment agent.

[0359] [Table 6]

[0360]

[0361] As shown in Table 6, Example 24, which used a liquid crystal alignment agent containing polymer [A], achieved good evaluations for liquid crystal orientation, initial VHR, and VHR reliability, and an optimal evaluation for film strength. In contrast, Comparative Example 6, which used a liquid crystal alignment agent not containing polymer [A], achieved a "Fair" evaluation for film strength (friction resistance) and a "Poor" evaluation for film strength (keystroke resistance).

[0362] [Example 25: Optical VA-Type Liquid Crystal Display Element]

[0363] 1. Preparation of liquid crystal alignment agent

[0364] A solution containing 30 parts by mass of the polymer (MI-1) obtained in Synthesis Example 32 and a solution containing 70 parts by mass of the polymer (PAA-14) obtained in Synthesis Example 14 were mixed and diluted with NMP and BC to prepare a solution having a solvent composition of NMP / BC = 80 / 20 (mass ratio) and a solid content concentration of 3.5% by mass. The solution was filtered through a filter with a pore size of 0.2 μm to prepare a liquid crystal aligning agent (AL-29).

[0365] 2. Manufacturing of VA-type liquid crystal display elements

[0366] The prepared liquid crystal alignment agent (AL-29) was applied to the transparent electrode surface of a glass substrate with a transparent electrode containing an ITO film using a spinner and pre-baked on a hot plate at 80°C for 1 minute. Then, in an oven in which the interior of the chamber was purged with nitrogen, the coating was heated at 230°C for 1 hour to form a film with a thickness of 0.1 μm. Subsequently, a Hg-Xe lamp and a Glan-Taylor prism were used to irradiate the surface of the coating with 1,000 J / m2 of polarized ultraviolet light containing a bright line of 313 nm from a direction inclined at 40° from the normal line of the substrate. 2 The same operation is repeated to prepare a pair (two) of substrates having liquid crystal alignment films.

[0367] An epoxy resin adhesive containing 3.5 μm diameter alumina spheres was applied to the periphery of the surface of one of the substrates having the liquid crystal alignment film by screen printing. The liquid crystal alignment film surfaces of the two substrates were then placed facing each other and pressure-bonded so that the optical axes of the ultraviolet rays projected onto the substrate surfaces were antiparallel. The adhesive was then thermally cured at 150°C for 1 hour. Subsequently, a negative liquid crystal (MLC-6608, manufactured by Merck) was injected into the gap between the substrates through the liquid crystal injection port, and the liquid crystal injection port was sealed with an epoxy adhesive. Furthermore, to remove the flow alignment during liquid crystal injection, the substrates were heated at 130°C and then slowly cooled to room temperature.

[0368] 3. Evaluation

[0369] The liquid crystal cell produced in 2. above was evaluated for liquid crystal orientation, initial VHR, VHR reliability, and film strength by the same method as in Example 2. The evaluation results are shown in Table 7.

[0370] [Comparative Example 7]

[0371] A liquid crystal alignment agent was prepared in the same manner as in Example 25, except that the composition of the liquid crystal alignment agent was changed as shown in Table 7. Furthermore, using the resulting liquid crystal alignment agent, a photo-VA liquid crystal cell was produced in the same manner as in Example 25, and various evaluations were performed. The results are shown in Table 7. In Table 7, the values ​​in the polymer column represent the blending ratio (parts by mass) of each polymer in terms of solid content relative to 100 parts by mass of the total amount of the polymer components used in the preparation of the liquid crystal alignment agent.

[0372] [Table 7]

[0373]

[0374] As shown in Table 7, Example 25, which used a liquid crystal alignment agent containing polymer [A], achieved good evaluations for liquid crystal orientation, initial VHR, and VHR reliability, and an optimal evaluation for film strength. In contrast, Comparative Example 7, which used a liquid crystal alignment agent not containing polymer [A], achieved a "Fair" evaluation for film strength (friction resistance) and a "Poor" evaluation for film strength (keystroke resistance).

[0375] From the above results, it was revealed that a liquid crystal aligning agent containing a polymer having partial structure (a) in the main chain can provide a liquid crystal element having good liquid crystal orientation, high voltage holding ratio, and excellent reliability, and also can obtain high cured film strength.

Claims

1. A liquid crystal aligning agent comprising a polymer [A] having a partial structure (a) represented by the following formula (1) in its main chain, In formula (1), R 1 and R 2 are independently a divalent chain hydrocarbon group having 1 to 20 carbon atoms, and an arbitrary methylene group possessed by the chain hydrocarbon group having 2 to 20 carbon atoms is not adjacent to each other, and is optionally substituted by -O-, -S-, -CO-, -COO-, -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O- or -NR 7 -CO-NR 8 -substituted divalent group, divalent nitrogen-containing non-aromatic heterocyclic group, -O- or -NR 7 -;R 3 and R 4 are independently a hydrogen atom, a halogen atom or an alkyl group having 1 to 3 carbon atoms, or R 3 With R 4 Combined with R 3 Bonded carbon and R 4 The carbon atoms to which they are bonded together form a ring structure; R 7 and R 8 are each independently a hydrogen atom or a monovalent organic group; "*" represents a bonding bond. 2 . The liquid crystal aligning agent according to claim 1 , wherein the polymer [A] contains a structural unit derived from a diamine having the partial structure (a).

3. The liquid crystal aligning agent according to claim 2, wherein the diamine is a compound represented by the following formula (2): In formula (2), A 1 and A 2 are independently a single bond, a divalent alicyclic group or a divalent aromatic ring group; m1 is an integer from 1 to 3; R 1 、R 2 、R 3 and R 4 Same meaning as in formula (1); when m1 is 2 or 3, multiple R 1 ~R 4 Same as or different from each other. The liquid crystal aligning agent according to claim 1 , wherein the polymer [A] contains a structural unit derived from a tetracarboxylic acid derivative having the partial structure (a).

5. The liquid crystal alignment agent according to claim 4, wherein the tetracarboxylic acid derivative is at least one selected from the group consisting of a compound represented by the following formula (3) and a compound represented by the following formula (4), In formula (3) and formula (4), A 3 and A 4 are independently a trivalent aromatic ring group or an aliphatic ring group; m2 is an integer of 1 to 3; n1 and n2 are independently an integer of 1 to 3; R 1 、R 2 、R 3 and R 4 It has the same meaning as the formula (1); when m2 is 2 or 3, multiple R 1 ~R 4 Same as or different from each other. The liquid crystal alignment agent according to claim 1 , wherein the polymer [A] is at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide. The liquid crystal aligning agent according to claim 6 , wherein the polymer [A] contains a structural unit derived from an alicyclic tetracarboxylic dianhydride. 8 . The liquid crystal aligning agent according to claim 1 , further comprising a polymer [Q] not having the partial structure (a). 9 . A liquid crystal alignment film formed by using the liquid crystal alignment agent according to claim 1 . 10 . A liquid crystal element comprising the liquid crystal alignment film according to claim 9 .

11. A polyamic acid, polyamic acid ester and polyimide having a partial structure represented by the following formula (1) in the main chain, In formula (1), R 1 and R 2 are independently a divalent chain hydrocarbon group having 1 to 20 carbon atoms, and an arbitrary methylene group possessed by the chain hydrocarbon group having 2 to 20 carbon atoms is not adjacent to each other, and is optionally substituted by -O-, -S-, -CO-, -COO-, -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O- or -NR 7 -CO-NR 8 -substituted divalent group, divalent nitrogen-containing non-aromatic heterocyclic group, -O- or -NR 7 -;R 3 and R 4 are independently a hydrogen atom, a halogen atom or an alkyl group having 1 to 3 carbon atoms, or R 3 With R 4 Combined with R 3 Bonded carbon and R 4 The carbon atoms to which they are bonded together form a ring structure; R 7 and R 8 are each independently a hydrogen atom or a monovalent organic group; "*" represents a bonding bond.

12. A method for producing a diamine, comprising using a compound represented by the following formula (5) as a raw material to produce a diamine represented by the following formula (2). In formula (5), R 9 A single bond or a divalent organic group In formula (2), A 1 and A 2 are independently a single bond, a divalent alicyclic group or a divalent aromatic ring group; R 1 and R 2 are independently a divalent chain hydrocarbon group having 1 to 20 carbon atoms, and an arbitrary methylene group possessed by the chain hydrocarbon group having 2 to 20 carbon atoms is not adjacent to each other, and is optionally substituted by -O-, -S-, -CO-, -COO-, -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O- or -NR 7 -CO-NR 8 -substituted divalent group, divalent nitrogen-containing non-aromatic heterocyclic group, -O- or -NR 7 -;R 3 and R 4 are independently a hydrogen atom, a halogen atom or an alkyl group having 1 to 3 carbon atoms, or R 3 With R 4 Combined with R 3 Bonded carbon and R 4 The carbon atoms to which they are bonded together form a ring structure; R 7 and R 8 are independently a hydrogen atom or a monovalent organic group; m1 is an integer of 1 to 3; when m1 is 2 or 3, multiple R 1 ~R 4 Same as or different from each other.

13. A method for producing tetracarboxylic dianhydride, comprising using a compound represented by the following formula (5) as a raw material to produce tetracarboxylic dianhydride represented by the following formula (3) and formula (4), In formula (5), R 9 A single bond or a divalent organic group In formula (3) and formula (4), A 3 and A 4 are independently a trivalent aromatic ring group or an aliphatic ring group; R 1 and R 2 are independently a divalent chain hydrocarbon group having 1 to 20 carbon atoms, and an arbitrary methylene group possessed by the chain hydrocarbon group having 2 to 20 carbon atoms is not adjacent to each other, and is optionally substituted by -O-, -S-, -CO-, -COO-, -NR 7 -、-NR 7 -NR 8 -、-NR 7 -CO-O- or -NR 7 -CO-NR 8 -substituted divalent group, divalent nitrogen-containing non-aromatic heterocyclic group, -O- or -NR 7 -;R 3 and R 4 are independently a hydrogen atom, a halogen atom or an alkyl group having 1 to 3 carbon atoms, or R 3 With R 4 Combined with R 3 Bonded carbon and R 4 The carbon atoms to which they are bonded together form a ring structure; R 7 and R 8 are independently a hydrogen atom or a monovalent organic group; m2 is an integer of 1 to 3; n1 and n2 are independently an integer of 1 to 3; when m2 is 2 or 3, multiple R 1 ~R 4 Same as or different from each other.

14. A method for producing a polymer, comprising producing the polyamic acid, polyamic acid ester, and polyimide according to claim 11 by polymerizing monomers containing at least one compound selected from the group consisting of a diamine obtained by the production method according to claim 12 and a tetracarboxylic dianhydride obtained by the production method according to claim 13.

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