Liquid crystal aligning agent, liquid crystal alignment film, liquid crystal element, polymer, and diamine

Abstract

The invention relates to a liquid crystal aligning agent, a liquid crystal alignment film, a liquid crystal element, a polymer and diamine. The liquid crystal aligning agent contains a polymer containing a structural unit derived from a diamine represented by formula (0). In formula (0), R1 and R2 are each independently a halogen atom or a monovalent organic group. Ar1 and Ar2 are each independently a group obtained by removing (p + 2) hydrogen atoms from a benzene ring, a naphthalene ring, or a biphenyl ring. And each of p and q independently represents an integer of 0-4. X1 and X2 are each independently a single bond or a divalent organic group. And Y1 is-CO-CO-,-SO2-,-CO-NR5 <-> * N or-SO2-NR5 <-> * N. And R5 represents a hydrogen atom or a monovalent organic group. '* N' is a bonding bond with a nitrogen atom to which '-COOZ1' is bonded. And Z1 represents a monovalent organic group.

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 compound, and in particular to a liquid crystal alignment agent, a liquid crystal alignment film, a liquid crystal element, a polymer and a diamine. Background Art

[0002] Liquid crystal elements are widely used in televisions, mobile devices, various monitors, and the like. In liquid crystal elements, the liquid crystal molecules in the liquid crystal cell are oriented by an organic film, i.e., a liquid crystal alignment film, formed on a substrate. As a method for obtaining an organic film with a liquid crystal orientation restriction force, it has been known in the past to rub an organic film formed using a polymer composition, to obliquely evaporate silicon oxide, to form a monomolecular film having a long-chain alkyl group, to irradiate a photosensitive organic film with light (photo-orientation method), and the like. Among these, rubbing is generally used in terms of simplicity and good orientation of liquid crystal molecules. In addition, the photo-orientation method can impart uniform liquid crystal orientation to the photosensitive organic film while suppressing the generation of static electricity or dust, and can also perform precise control of the liquid crystal orientation direction, and therefore various studies have been conducted in recent years.

[0003] In recent years, liquid crystal elements have been used in a wide range of devices and applications, from large-screen LCD televisions to small display devices such as smartphones and tablet personal computers. Liquid crystal elements are being demanded to achieve higher performance. Against this backdrop, further improvement in the display quality of liquid crystal elements is more important than ever before. To achieve this, various liquid crystal alignment agents have been proposed (for example, see Patent Documents 1 and 2).

[0004] Patent Documents 1 and 2 disclose a liquid crystal alignment agent for the purpose of obtaining a liquid crystal alignment film with less cutting or scratching on the film surface during friction treatment (excellent friction resistance), and comprising a polyimide precursor or polyimide obtained by using a diamine having a specific structure composed of a (thio)urea bond, a spacer portion, a linking group and two aminophenyl structures.

[0005] [Prior art literature]

[0006] [Patent Document]

[0007] [Patent Document 1] International Publication No. 2010 / 053128

[0008] [Patent Document 2] International Publication No. 2011 / 136375 Summary of the Invention

[0009] [Problems to be solved by the invention]

[0010] Most of the previous liquid crystal alignment agents that can form a coating film with high friction resistance and good mechanical properties are prone to produce residual images (hereinafter also referred to as "AC residual images") when an alternating current voltage is applied, that is, the mechanical properties of the film and the alternating current (AC) residual image characteristics of the liquid crystal element are in a trade-off relationship. In addition, the AC residual image is a residual image caused by the deviation of the direction of the initial orientation from the original direction of the liquid crystal element due to the long-term driving of the liquid crystal element. In addition, when using the optical orientation method, compared with the friction method, there is a tendency that the orientation restriction force of the liquid crystal molecules is not sufficient and AC residual images are easily generated. In order to meet the requirements of further high performance in recent years, as a liquid crystal alignment agent, a liquid crystal alignment agent is sought that makes the mechanical properties of the liquid crystal alignment film good and the liquid crystal orientation good, and at the same time can sufficiently reduce the AC residual image in the liquid crystal element.

[0011] The present invention has been made in view of the above circumstances, and one object thereof is to provide a liquid crystal aligning agent which can provide a liquid crystal element having good mechanical properties of a liquid crystal aligning film and good liquid crystal orientation and AC afterimage properties.

[0012] [Technical means to solve the problem]

[0013] According to the present invention, in one embodiment, there is provided a polymer containing a single liquid crystal alignment agent element having a structure derived from a diamine represented by the following formula (0).

[0014] [Chemistry 1]

[0015]

[0016] (In formula (0), R 1 and R 2 are independently a halogen atom or a monovalent organic group; Ar 1 and Ar 2 are each independently a group formed by removing (p+2) hydrogen atoms from a benzene ring, a naphthalene ring, or a biphenyl ring; p and q are each independently an integer from 0 to 4; X 1 and X 2 are independently a single bond or a divalent organic group; Y 1 -CO-CO-, -SO2-, -CO-NR 5 -* N or -SO2-NR 5 -* N ; R 5 is a hydrogen atom or a monovalent organic group; "* N " is the same as "-COOZ 1 "The bond to the nitrogen atom to which Z is bonded; 1 (monovalent organic radical)

[0017] According to the present invention, in another embodiment, a liquid crystal alignment film is provided, which is formed using the liquid crystal alignment agent. In addition, according to the present invention, in yet another embodiment, a liquid crystal element is provided, which includes the liquid crystal alignment film. Furthermore, according to the present invention, in yet another embodiment, a polymer is provided, which includes a structural unit derived from a diamine represented by the formula (0). In addition, according to the present invention, in yet another embodiment, a diamine is provided, which is represented by the formula (0).

[0018] [Effects of the Invention]

[0019] According to the liquid crystal aligning agent of this invention, the dynamic characteristics of a liquid crystal aligning film are favorable, and a liquid crystal element which is favorable in liquid crystal orientation and AC residual image characteristics can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a graph showing the measurement results of the 1H-NMR spectrum of compound (DA-1).

[0021] Figure 2 It is a graph showing the measurement results of the 13C-NMR spectrum of compound (DA-1).

[0022] Figure 3 It is a graph showing the measurement results of the 1H-NMR spectrum of compound (DA-2).

[0023] Figure 4 It is a graph showing the measurement results of the 13C-NMR spectrum of compound (DA-2).

[0024] Figure 5 It is a graph showing the measurement results of the 1H-NMR spectrum of compound (DA-3).

[0025] Figure 6 It is a graph showing the measurement results of the 13C-NMR spectrum of compound (DA-3).

[0026] Figure 7 It is a graph showing the measurement results of the 1H-NMR spectrum of compound (DA-4).

[0027] Figure 8 It is a graph showing the measurement results of the 13C-NMR spectrum of compound (DA-4).

[0028] Figure 9 It is a graph showing the measurement results of the 1H-NMR spectrum of compound (DA-6).

[0029] Figure 10 It is a graph showing the measurement results of the 13C-NMR spectrum of compound (DA-6). DETAILED DESCRIPTION

[0030] Hereinafter, matters related to the embodiments of the present disclosure will be described in detail.

[0031] Here, in this specification, the numerical range described using "to" means that the numerical values ​​described before and after the "to" are included as the lower limit and upper limit. The so-called "structural unit" refers to a unit that mainly constitutes the main chain structure and is a unit containing at least two or more in the main chain structure. Typically, a structural unit is a repeating unit composed of a single monomer. In addition, a structural unit can also be obtained by reacting a repeating unit having a reactive group with a compound having a functional group that can react with the reactive group.

[0032] In this specification, the term "hydrocarbon group" means a chain hydrocarbon group, an alicyclic hydrocarbon group, and an aromatic hydrocarbon group. The so-called "chain hydrocarbon group" refers to a straight-chain hydrocarbon group and a branched hydrocarbon group that does not contain a ring structure but only a chain structure. Among them, it may be saturated or unsaturated. The so-called "alicyclic hydrocarbon group" refers to a hydrocarbon group that only contains the structure of an alicyclic hydrocarbon as a ring structure, and does not contain an aromatic ring structure. Among them, it is not necessary to contain only the structure of an alicyclic hydrocarbon, and a group having a chain structure in a part thereof is also included. 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 contain only the aromatic ring structure, and a chain structure or an alicyclic hydrocarbon structure may be contained in a part thereof. The so-called "organic group" refers to an atomic group formed by removing any hydrogen atom from a compound containing carbon (i.e., an organic compound).

[0033] The "main chain" of a polymer refers to the "trunk" portion of the polymer containing the longest atomic chain. This "trunk" portion may contain a ring structure. For example, "having a specific structure in the main chain" means that the specific structure constitutes a portion of the main chain. A "side chain" refers to a portion branching from the "trunk" portion of a polymer.

[0034] Liquid Crystal Alignment Agent

[0035] The liquid crystal aligning agent of the present disclosure and its production method will be described. The liquid crystal aligning agent of the present disclosure contains a polymer (hereinafter also referred to as "polymer (P)") containing a structural unit derived from a diamine (hereinafter also referred to as "specific diamine") represented by the following formula (0).

[0036] [Chemistry 2]

[0037]

[0038] (In formula (0), R 1 and R 2 are independently a halogen atom or a monovalent organic group; Ar 1and Ar 2 are each independently a group formed by removing (p+2) hydrogen atoms from a benzene ring, a naphthalene ring, or a biphenyl ring; p and q are each independently an integer from 0 to 4; X 1 and X 2 are independently a single bond or a divalent organic group; Y 1 -CO-CO-, -SO2-, -CO-NR 5 -* N or -SO2-NR 5 -* N ; R 5 is a hydrogen atom or a monovalent organic group; "* N " is the same as "-COOZ 1 "The bond to the nitrogen atom to which Z is bonded; 1 (monovalent organic radical)

[0039] Hereinafter, the polymer (P) contained in the liquid crystal aligning agent of the present disclosure and the components optionally formulated will be described in detail. In addition, unless otherwise specified, each component may be used alone or in combination of two or more.

[0040] <Polymer (P)>

[0041] ·Specific diamine

[0042] In the formula (0), R 1 or R 2 Examples of the halogen atom represented by include fluorine atom, chlorine atom, bromine atom, iodine atom, and the like. 1 or R 2 The monovalent organic group represented by may include a monovalent hydrocarbon group having 1 to 6 carbon atoms, and any methylene group in the monovalent hydrocarbon group represented by -O-, -S-, -CO-, -COO-, -OCO-, -NR 10 -、-NR 10 -CO-, -CO-NR 10 - or a group containing a heteroatom substituted with a group having 1 to 6 carbon atoms (hereinafter referred to as "group R a ”), a monovalent hydrocarbon group or a group R a A carbon number 1 to 6 group in which any hydrogen atom in is replaced by a substituent. 10 It is a hydrogen atom or a monovalent hydrocarbon group.

[0043] Examples of the monovalent hydrocarbon group having 1 to 6 carbon atoms include a linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched alkenyl group having 2 to 6 carbon atoms, a linear or branched alkynyl group having 2 to 6 carbon atoms, a monovalent alicyclic hydrocarbon group having 3 to 6 carbon atoms, and a phenyl group. 1 or R 2When the group represented by has a substituent, examples of the substituent include a halogen atom, a hydroxyl group, a cyano group, a nitro group, a carboxyl group, a primary amino group, a secondary amino group, and a tertiary amino group.

[0044] From the viewpoint of the polymerizability and availability of the specific diamine, R 1 or R 2 The monovalent organic group represented by is preferably an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a phenyl group, -COR 11 or -NR 12 R 13 (Among them, R 11 、R 12 and R 13 Each independently represents an alkyl group having 1 to 3 carbon atoms), more preferably an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, or a phenyl group, and still more preferably an alkyl group having 1 to 3 carbon atoms.

[0045] From the perspective of aggregation and accessibility, R 1 or R 2 Particularly preferred are alkyl groups having 1 to 3 carbon atoms.

[0046] p is preferably 0 to 2, more preferably 0 or 1. q is preferably 0 to 2, more preferably 0 or 1.

[0047] Ar 1 or Ar 2 The group represented is a group formed by removing (p+2) hydrogen atoms from a benzene ring, a naphthalene ring or a biphenyl ring. In terms of ease of synthesis of the specific diamine and further improvement of the liquid crystal orientation of the liquid crystal alignment film obtained using the polymer (P), Ar 1 and Ar 2 It is preferably a group formed by removing (p+2) hydrogen atoms from a benzene ring or a biphenyl ring.

[0048] As X 1 or X 2 Examples of the divalent organic group include a divalent hydrocarbon group having 1 to 12 carbon atoms, an oxygen atom, a sulfur atom, -CO-, -SO2-, -NR 6 -, -C=N- or any methylene group in a divalent hydrocarbon group having 2 to 12 carbon atoms, such as an oxygen atom, a sulfur atom, -CO-, -SO2-, -NR 6 - or -C=N-(wherein, R 6 is a divalent group substituted with a hydrogen atom or a monovalent organic group. 1 or X 2 The divalent organic group represented by is preferably a divalent hydrocarbon group having 1 to 12 carbon atoms or any methylene group in a divalent hydrocarbon group having 2 to 12 carbon atoms, connected via an oxygen atom, a sulfur atom, -CO-, -SO2-, -NR 6- or -C=N-substituted divalent group.

[0049] In X 1 or X 2 Among the divalent organic groups represented, examples of divalent hydrocarbon groups having 1 to 12 carbon atoms include divalent chain hydrocarbon groups, divalent alicyclic hydrocarbon groups, and divalent aromatic hydrocarbon groups. From the perspective of achieving better AC afterimage characteristics of the liquid crystal element, divalent chain hydrocarbon groups are preferred. Examples thereof include linear or branched alkanediyl groups having 1 to 12 carbon atoms, linear or branched alkenediyl groups having 2 to 12 carbon atoms, and linear or branched alkynediyl groups having 2 to 12 carbon atoms. Among these, linear alkanediyl groups or alkenediyl groups having 1 to 12 carbon atoms are particularly preferred.

[0050] In X 1 or X 2 When the divalent organic group represented is a divalent group in which any methylene group in a divalent hydrocarbon group having 2 to 12 carbon atoms is substituted by a group containing a hetero atom such as an oxygen atom, specific examples of the divalent hydrocarbon group having 2 to 12 carbon atoms in which the methylene group is substituted by a group containing a hetero atom include X 1 or X 2 In the case of a divalent hydrocarbon group having 1 to 12 carbon atoms, a group having 2 or more carbon atoms among the groups described above. Among these, a divalent chain hydrocarbon group is particularly preferred, and a linear alkanediyl group or alkenediyl group having 2 to 12 carbon atoms is preferred.

[0051] About-NR 6 -, R 6 The monovalent organic group represented is preferably a monovalent hydrocarbon group or a thermally degradable group having 1 to 12 carbon atoms. Examples of the monovalent hydrocarbon group having 1 to 12 carbon atoms include a monovalent chain hydrocarbon group, a monovalent alicyclic hydrocarbon group, and a monovalent aromatic hydrocarbon group. Among these, an alkyl group having 1 to 6 carbon atoms is preferred, and an alkyl group having 1 to 4 carbon atoms is more preferred.

[0052] Examples of thermally detachable groups include carbamate-based detachable groups, amide-based detachable groups, imide-based detachable groups, and sulfonamide-based detachable groups. Among these, carbamate-based detachable groups are preferred in terms of their high thermal detachability. Specific examples of carbamate-based detachable groups include isopropyloxycarbonyl, tert-butoxycarbonyl (Boc group), 2-methyl-2-butyloxycarbonyl, benzyloxycarbonyl, 1,1-dimethyl-2-halogenated ethyloxycarbonyl, allyloxycarbonyl, 2-(trimethylsilyl)ethoxycarbonyl, and 9-fluorenylmethyloxycarbonyl (F-moc group). Among these, branched alkyloxycarbonyl groups having 3 to 6 carbon atoms are particularly preferred, and tert-butoxycarbonyl (Boc group) is particularly preferred.

[0053] In the above, R6 A hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or a thermally cleavable group is preferred. Among these, a thermally cleavable group is more preferred from the perspective of ensuring the solubility of the polymer while obtaining a liquid crystal element with more excellent AC afterimage characteristics. An alkyloxycarbonyl group having a branched alkyl group having 3 to 6 carbon atoms is more preferred, and a Boc group is even more preferred.

[0054] Y 1 -CO-CO-, -SO2-, -CO-NR 5 -* N or -SO2-NR 5 -* N Among these, -CO-CO- or -CO-NR is preferred in terms of further improving the mechanical properties of the liquid crystal alignment film. 5 -* N , more preferably -CO-NR 5 -* N As R 5 Specific examples and preferred examples of the monovalent organic group represented by include the following: 6 In addition, "* N " is the nitrogen atom (i.e., -COOZ 1 The nitrogen atom to which it is bound).

[0055] Z 1 The monovalent organic group represented by is preferably -COOZ 1 The base that is separated and replaced by a hydrogen atom makes -COOZ 1 From the perspective of good thermal separation, Z 1 It is preferably a monovalent aliphatic hydrocarbon group having 1 to 6 carbon atoms, more preferably a linear or branched alkyl group having 1 to 6 carbon atoms, further preferably a branched alkyl group having 3 to 6 carbon atoms, and particularly preferably a tert-butyl group.

[0056] The specific diamine has a structure in which two aminoaryl groups (i.e., a group represented by -Ar-NH2 (wherein Ar is a substituted or unsubstituted benzene ring, naphthalene ring or biphenyl ring)) are bonded to a primary amino group on a substituted or unsubstituted benzene ring, naphthalene ring or biphenyl ring in one molecule, and the two aminoaryl groups in one molecule are represented by "-X 1 -Y 1 -N(COOZ 1 )-X 2 -" represents a structure of divalent groups linked together. Here, "-Y 1 -N(COOZ 1 )-" contains multiple hydrogen bonding functional groups (hydrogen bonding groups). Specifically, "-Y 1 -N(COOZ1 )-" has the following partial structure, namely, a group that can become a hydrogen bond donor (-NR-, R is a hydrogen atom or a monovalent organic group) and a group that can become a hydrogen bond acceptor (-CO-, -SO2-), and a partial structure formed by a continuous total of 3 or more groups that can become hydrogen bond donors and groups that can become hydrogen bond acceptors (hereinafter also referred to as "multi-point hydrogen bond structure"). It is believed that the polymer (P) easily exerts intermolecular interactions between polymers by having such a multi-point hydrogen bond structure in the main chain, and further, the heat rearrangement or elongation is excellent due to the chain structure derived from the multi-point hydrogen bond structure. In addition, "-SO2-" has a structure formed by two oxo groups (=O) bonded to sulfur, so it can be said to have two continuous hydrogen bond acceptors.

[0057] Regarding the multi-point hydrogen bond structure of the polymer (P), in detail, "-Y 1 -N(COOZ 1 )-" and Y 1 Correspondingly becomes -CO-CO-NR N -、-SO2-NR N -、-CO-NR 5 -NR N -、-SO2-NR 5 -NR N -(R N for-COOZ 1 The groups represented by the groups; the same below). Regarding the arrangement of the groups that can become hydrogen bond donors and the groups that can become hydrogen bond acceptors in these partial structures, when the groups that can become hydrogen bond donors are represented by "D" and the groups that can become hydrogen bond acceptors are represented by "A", they become "AAD", "AAD", "ADD", and "AADD" respectively, and have a structure consisting of two consecutive groups that can become hydrogen bond donors or groups that can become hydrogen bond acceptors. Therefore, it is believed that the heat rearrangement or extensibility is highly maintained, while the hydrogen bonding property is improved. Furthermore, it is speculated that at least one of the -NR- in the multi-point hydrogen bond structure possessed by the polymer (P) is -N(COOZ 1 )-, it is also possible to improve the AC afterimage characteristics of the liquid crystal element.

[0058] Preferred examples of the specific diamine include compounds represented by the following formula (1).

[0059] [Chemistry 3]

[0060]

[0061] (In formula (1), R 1 and R 2 are each independently a halogen atom or a monovalent organic group; p and q are each independently an integer of 0 to 4; X1 and X 2 are independently a single bond or a divalent organic group; Y 1 -CO-CO-, -SO2-, -CO-NR 5 -* N or -SO2-NR 5 -* N ; R 5 is a hydrogen atom or a monovalent organic group; "* N " is the same as "-COOZ 1 "The bond to the nitrogen atom to which Z is bonded; 1 (monovalent organic radical)

[0062] In the formula (1), R 1 、R 2 , p, q, X 1 、X 2 、Y 1 and Z 1 Each symbol has the same meaning as in the above formula (0), and the description of the above formula (0) can be cited for specific examples and preferred examples of each symbol.

[0063] As a specific example of the specific diamine, the compound etc. represented by the following formula are mentioned.

[0064] [Chemistry 4]

[0065]

[0066] [Chemistry 5]

[0067]

[0068] [Chemistry 6]

[0069]

[0070] [Chemistry 7]

[0071]

[0072] [Chemistry 8]

[0073]

[0074] [Chemistry 9]

[0075]

[0076] In terms of making the mechanical properties of the liquid crystal alignment film more excellent, the specific diamine preferably has a total of four or more groups (-NR N-) and a group that can become a hydrogen bond acceptor (a group formed by bonding an oxo group to a carbon atom or a sulfur atom), more preferably a compound containing -CO-NR N -NR N -CO-. In addition, regarding the total number of groups that can become hydrogen bond donors and groups that can become hydrogen bond acceptors per molecule of the specific diamine, -SO2- is counted as a group having two consecutive hydrogen bond acceptors as described above. In addition, from the viewpoint of the liquid crystal orientation of the liquid crystal element and the mechanical properties of the liquid crystal alignment film, the specific diamine is preferably X in the above formula (0). 1 and X 2 At least one of the alkanediyl groups has an alkanediyl group, more preferably 1 and X 2 In both cases, there is an alkanediyl group, and preferably in X 1 and X 2 Both have a straight-chain alkanediyl group.

[0077] [Synthesis of specific diamines]

[0078] Specific diamines can be synthesized by appropriately combining conventional methods of organic chemistry. An example of a method for synthesizing specific diamines includes the following: first, a dinitro intermediate having a nitro group in place of the primary amino group in the target diamine is synthesized; then, the nitro group of the obtained dinitro intermediate is nitroaminated using an appropriate reduction system.

[0079] The method for synthesizing the dinitro intermediate can be appropriately selected according to the molecular structure of the target diamine. 1 The compound of -CO-CO- can be prepared by combining a nitrophenyl group with a group X 1 The amine compound reacts with oxalylchloride to introduce the -COOZ group. 1 The corresponding dinitro intermediate is obtained. 1 The compound of -SO2- can be prepared by combining a nitrophenyl group with a group X 1 The amine hydrochloride reacts with sulfonamide to introduce the -COOZ 1 And obtain the corresponding dinitro intermediate. In addition, Y in the formula (0) 1 -CO-NR 5 - can be obtained by combining a nitrophenyl group with a group X 1 The carboxylic acid reacts with hydrazine and then introduces the -COOZ group 1 Each reaction can be carried out in a suitable organic solvent in the presence of a catalyst as needed.

[0080] The reduction reaction of the dinitro intermediate can preferably be carried out in an organic solvent using a catalyst such as palladium-carbon or platinum-carbon and a reducing agent such as hydrogen or hydrazine. Alternatively, the reaction can be carried out using a metal such as zinc, iron, tin, or nickel and a proton source such as hydrochloric acid or ammonium chloride. Examples of organic solvents used herein include ethyl acetate, toluene, tetrahydrofuran, and alcohols. The method for synthesizing the specific diamine is not limited to the method described above.

[0081] As long as the polymer (P) contains structural units derived from a specific diamine, the type of its main skeleton is not particularly limited. The polymer (P) is preferably a condensation polymer obtained by using a diamine containing a specific diamine as a monomer, and examples thereof include polymers having a main skeleton of polyamic acid, polyamic acid ester, polyimide, polyamine, polyenamine, polyamide, polyamideimide, polyurea or polyimine. In addition, the so-called polyenamine is a polymer having a carbon-carbon double bond at the adjacent position of the amino group of the polyamine, and examples thereof include: polyenamino ketone, polyenamino ester, polyenamino nitrile, polyenamino sulfonyl, etc.

[0082] In order to obtain a liquid crystal element with better liquid crystal orientation and voltage holding characteristics, the polymer (P) is preferably at least one selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, polyamide, polyamideimide, polyurea, and polyimide. Among these, the polymer (P) is particularly preferably at least one selected from the group consisting of polyamic acid, polyamic acid ester, and polyimide.

[0083] [Synthesis of polymer (P)]

[0084] The synthesis method of polymer (P) is not particularly limited and can be suitably selected according to the type of main skeleton. For example, when polymer (P) is at least one selected from the group consisting of polyamic acid, polyamic acid ester and polyimide, polymer (P) can be obtained by, for example, a method comprising polycondensing a tetracarboxylic acid derivative with a diamine comprising a specific diamine. In addition, tetracarboxylic acid derivatives include tetracarboxylic dianhydride, tetracarboxylic acid dihalide and tetracarboxylic acid diester dihalide. Hereinafter, the details of polyamic acid, polyamic acid ester and polyimide are described.

[0085] (Polyamic acid)

[0086] When the polymer (P) is a polyamic acid, the polyamic acid (hereinafter also referred to as “polyamic acid (P)”) can be obtained by reacting tetracarboxylic dianhydride with diamine (polycondensation reaction).

[0087] Tetracarboxylic dianhydride

[0088] Examples of the tetracarboxylic dianhydride used for the synthesis of the polyamic acid (P) include aliphatic tetracarboxylic dianhydride and aromatic tetracarboxylic dianhydride. Examples of the aliphatic tetracarboxylic dianhydride include chain tetracarboxylic dianhydride and alicyclic tetracarboxylic dianhydride.

[0089] Specific examples of tetracarboxylic dianhydrides include chain tetracarboxylic dianhydrides such as 1,2,3,4-butanetetracarboxylic dianhydride and ethylenediaminetetraacetic dianhydride.

[0090] Examples of the alicyclic tetracarboxylic dianhydride include 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-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, and 3-oxabicyclo[3,2. 1] octane-2,4-dione-6-spiro-3'-(tetrahydrofuran-2',5'-dione), 5-(2,5-dioxotetrahydro-3-furyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, 3,5,6-tricarboxy-2-carboxymethylnorbornane-2:3,5:6-dianhydride, bicyclo[3.3.0]octane-2,4,6,8-tetracarboxylic acid 2:4,6:8-dianhydride, bicyclo[2.2.1]heptane-2,3,5,6-tetracarboxylic acid 2:3,5:6-dianhydride, 4,9-dioxatricyclo[5.3.1.0 2,6 ] undecane-3,5,8,10-tetraone, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, cyclopentanetetracarboxylic dianhydride, etc.;

[0091] Examples of the aromatic tetracarboxylic dianhydride include pyromellitic dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, p-phenylenebis(trimellitic acid monoester anhydride), ethylene glycol bis(trimellitic anhydride ester), 1,3-propylene glycol bis(trimellitic anhydride ester), 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 4,4'-diphthalic dianhydride, 4,4'-oxydiphthalic dianhydride, and 4,4'-carbonyldiphthalic anhydride. In addition, the tetracarboxylic dianhydrides described in Japanese Patent Application Laid-Open No. 2010-97188 can also be used.

[0092] In terms of improving the solubility of the polymer (P) and obtaining a liquid crystal alignment film exhibiting good voltage holding characteristics, the tetracarboxylic dianhydride preferably contains an aliphatic tetracarboxylic dianhydride, and more preferably contains an alicyclic tetracarboxylic dianhydride. Specifically, it is preferably at least one selected from the group consisting of 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic dianhydride, 2,4,6,8-tetracarboxybicyclo[3.3.0]octane-2:4,6:8-dianhydride, cyclopentanetetracarboxylic dianhydride, and cyclohexanetetracarboxylic dianhydride.

[0093] In the polyamic acid (P), the content ratio of the structural units derived from alicyclic tetracarboxylic dianhydride relative to the total amount of the structural units derived from tetracarboxylic dianhydride contained in the polyamic acid (P) is preferably 20 mol% or more, more preferably 30 mol% or more, further preferably 50 mol% or more, and particularly preferably 70 mol% or more.

[0094] Diamine

[0095] When synthesizing polyamic acid (P), as diamine, only specific diamine can be used. In addition, diamines different from the specific diamine (hereinafter also referred to as "other diamines") can be used together with the specific diamine. Examples of other diamines include aliphatic diamines, aromatic diamines, and diaminoorganosiloxanes. Examples of aliphatic diamines include chain diamines and alicyclic diamines.

[0096] Specific examples of other diamines include meta-xylenediamine and hexamethylenediamine as chain diamines, and 1,4-diaminocyclohexane and 4,4′-methylenebis(cyclohexylamine) as alicyclic diamines.

[0097] Specific examples of the aromatic diamine include p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylethane, 4,4'-diaminodiphenyl ether, 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, bis[2-(4-aminophenyl)ethyl]adipic acid, 1,4-bis(4-aminophenyl)-piperazine, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 2,2-bis[4-(4-aminophenoxy) Main chain diamines such as] phenyl] propane, 2,2-bis(4-aminophenyl)hexafluoropropane, 4,4'-(phenylenediisopropylidene) dianiline, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-[4,4'-propane-1,3-diylbis(piperidin-1,4-diyl)] diphenylamine, 4,4'-diaminobenzanilide, 4,4'-diaminostilbene, 4,4'-diaminostilbeneethyl urea, N,N'-bis(4-amino-2-pyridyl)-N,N'-bis(tert-butoxycarbonyl)ethylenediamine, N,N'-bis[2-(4-aminophenyl)ethyl]hexanediamide, and N,N'-bis[2-(4-aminophenyl)ethyl]-N,N'-bis(tert-butoxycarbonyl)hexanediamide;

[0098] Dodecyloxy-2,4-diaminobenzene, pentadecyloxy-2,4-diaminobenzene, hexadecyloxy-2,4-diaminobenzene, octadecyloxy-2,4-diaminobenzene, pentadecyloxy-2,5-diaminobenzene, octadecyloxy-2,5-diaminobenzene, cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-2,4-diaminobenzene, cholesteryloxy-2,4-diaminobenzene, cholesteryloxy-3,5-diaminobenzene, cholesteryloxy-2,4-diaminobenzene, cholesteryloxy-3,5-diaminobenzoate, 3,5-diaminobenzoate Side chain diamines such as cholesteryl aminobenzoate, lanostanyl 3,5-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, and a compound represented by the following formula (E-1) are also included.

[0099] [Chemistry 10]

[0100]

[0101] (In formula (E-1), X I and X II Each independently represents a single bond, -O-, *-COO- or *-OCO- (wherein "*" represents a bond to the diaminophenyl side); R I is an alkanediyl group having 1 to 3 carbon atoms; R II is a single bond or an alkanediyl group having 1 to 3 carbon atoms; R III is an alkyl, alkoxy, fluoroalkyl 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; wherein 1≦a+b+c≦3)

[0102] Examples of the compound represented by formula (E-1) include compounds represented by the following formulas (E-1-1) to (E-1-4).

[0103] [Chemistry 11]

[0104]

[0105] Specific examples of diaminoorganosiloxane include 1,3-bis(3-aminopropyl)-tetramethyldisiloxane, etc. In addition, as other diamines, diamines described in Japanese Patent Application Laid-Open No. 2010-97188 can also be used in addition to the above.

[0106] The proportion of the structural units derived from the specific diamine in the polymer (P) is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 20 mol% or more, relative to the total amount of the structural units derived from the diamine contained in the polymer (P). By setting the proportion of the structural units derived from the specific diamine within this range, the mechanical properties of the film and the liquid crystal orientation and AC afterimage properties of the liquid crystal cell can be further improved.

[0107] When the polymer (P) contains structural units derived from other diamines, the proportion of the structural units derived from other diamines in the polymer (P) is preferably 5 mol% or more, more preferably 10 mol% or more, and even more preferably 15 mol% or more, relative to the total amount of the structural units derived from diamines contained in the polymer (P). Furthermore, the proportion of the structural units derived from other diamines relative to the total amount of the structural units derived from diamines contained in the polymer (P) is preferably 95 mol% or less, more preferably 90 mol% or less, and even more preferably 80 mol% or less.

[0108] Synthesis of polyamic acid (P)

[0109] Polyamic acid (P) can be obtained by reacting tetracarboxylic dianhydride with diamine and, if necessary, a molecular weight modifier. The ratio of tetracarboxylic dianhydride to diamine used in the synthesis reaction of polyamic acid (P) 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.

[0110] 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 used.

[0111] The synthesis reaction of the polyamic acid (P) is preferably carried out in an organic solvent. The reaction temperature is preferably -20°C to 150°C, and the reaction time is preferably 0.1 hour to 24 hours.

[0112] Examples of the organic solvent used in the reaction include aprotic polar solvents, phenolic solvents, alcohols, ketones, esters, ethers, halogenated hydrocarbons, and hydrocarbons. A particularly preferred organic solvent is preferably 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 phenols, or a mixture of one or more of these with other organic solvents (e.g., butyl cellosolve, diethylene glycol diethyl ether, etc.). The amount (a) of the organic solvent used is preferably such that the total amount (b) of tetracarboxylic dianhydride and diamine is 0.1% by mass to 50% by mass relative to the total amount (a+b) of the reaction solution.

[0113] The reaction solution formed by dissolving polyamic acid (P) is obtained in the described manner. The reaction solution can be directly supplied to the preparation of liquid crystal alignment agent, and the polyamic acid (P) contained in the reaction solution can also be separated and then supplied to the preparation of liquid crystal alignment agent, or the separated polyamic acid (P) can also be refined and then supplied to the preparation of liquid crystal alignment agent. In the case where polyamic acid (P) is dehydrated and ring-closed to form polyimide, the reaction solution can be directly supplied to dehydration ring-closed reaction, and the polyamic acid (P) contained in the reaction solution can also be separated and then supplied to dehydration ring-closed reaction, or the separated polyamic acid (P) can also be refined and then supplied to dehydration ring-closed reaction. The separation and purification of polyamic acid (P) can be carried out according to known methods.

[0114] (Polyamic acid ester)

[0115] The polyamic acid ester (hereinafter also referred to as "polyamic acid ester (P)") as a polymer (P) can be obtained, for example, by the following methods: [I] a method of reacting the polyamic acid (P) obtained by the above-mentioned synthesis reaction with an esterifying agent; [II] a method of reacting a tetracarboxylic acid diester with a diamine containing a specific diamine; [III] a method of reacting a tetracarboxylic acid diester dihalide with a diamine containing a specific diamine.

[0116] In this specification, the term "tetracarboxylic acid diester" refers to a compound in which two of the four carboxyl groups of a tetracarboxylic acid are esterified and the remaining two are carboxyl groups. The term "tetracarboxylic acid diester dihalide" refers to a compound in which two of the four carboxyl groups of a tetracarboxylic acid are esterified and the remaining two are halogenated.

[0117] Examples of the esterifying agent used in method [I] include hydroxyl-containing compounds, acetal compounds, halides, and epoxy-containing compounds. Specific examples of these include alcohols such as methanol, ethanol, and propanol, and phenols such as phenol and cresol. Examples of acetal compounds include N,N-dimethylformamide diethyl acetal and N,N-diethylformamide diethyl acetal. Examples of halides include methyl bromide, ethyl bromide, octadecane bromide, methyl chloride, octadecane chloride, and 1,1,1-trifluoro-2-iodoethane. Examples of epoxy-containing compounds include propylene oxide.

[0118] The tetracarboxylic acid diester used in method [II] can be obtained, for example, by ring-opening the tetracarboxylic dianhydride exemplified in the description of the synthesis of polyamic acid (P) using an alcohol such as methanol or ethanol. Furthermore, the tetracarboxylic acid derivative used in method [II] may be solely a tetracarboxylic acid diester, or may be used in combination with a tetracarboxylic dianhydride.

[0119] The tetracarboxylic acid diester dihalide used in method [III] can be obtained, for example, by reacting the tetracarboxylic acid diester obtained in the above manner with an appropriate chlorinating agent such as thionyl chloride. Furthermore, the tetracarboxylic acid derivative used in method [III] may be solely the tetracarboxylic acid diester dihalide, but tetracarboxylic dianhydride may also be used in combination.

[0120] The polyamic acid ester (P) contained in the liquid crystal alignment agent may have only an amic acid ester structure, or may be a partially esterified product in which an amic acid structure and an amic acid ester structure coexist. The reaction solution formed by dissolving the polyamic acid ester (P) can be directly used for the preparation of the liquid crystal alignment agent, or the polyamic acid ester (P) contained in the reaction solution can be separated and then used for the preparation of the liquid crystal alignment agent, or the separated polyamic acid ester (P) can be refined and then used for the preparation of the liquid crystal alignment agent. The separation and purification of the polyamic acid ester (P) can be carried out according to known methods.

[0121] (Polyimide)

[0122] The polyimide (hereinafter also referred to as “polyimide (P)”) as the polymer (P) can be obtained by, for example, subjecting the polyamic acid (P) synthesized as described above to dehydration ring closure and imidization.

[0123] The polyimide (P) may be a fully imidized product obtained by dehydrating and ring-closing all the amic acid structures of the polyamic acid (P) as its precursor, or a partially imidized product obtained by dehydrating and ring-closing only a portion of the amic acid structure so that the amic acid structure and the imide ring structure coexist. The imidization rate of the polyimide (P) is preferably 20% or more, more preferably 30% to 99%. The imidization rate is a percentage representing 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 (P). Here, a portion of the imide ring may be an isoimide ring.

[0124] The dehydration ring-closure of the polyamic acid (P) is preferably carried out by heating the polyamic acid (P) or by dissolving the polyamic acid (P) in an organic solvent, adding a dehydrating agent and a dehydration ring-closure catalyst to the solution, and heating as needed.

[0125] In the method of adding a dehydrating agent and a dehydration ring-closure catalyst to a solution of polyamic acid (P), anhydrides such as acetic anhydride, propionic anhydride, and trifluoroacetic anhydride can be used as the dehydrating agent. The amount of the dehydrating agent used is preferably set to 0.01 mol to 20 mol relative to 1 mol of the amic acid structure of polyamic acid (P). As a dehydration ring-closure catalyst, for example, tertiary amines such as pyridine, collidine, dicollidine, triethylamine, and 1-methylpiperidine can be used. The amount of the dehydration ring-closure catalyst used is preferably set to 0.01 mol to 10 mol relative to 1 mol of the dehydrating agent used. As the organic solvent used in the dehydration ring-closure reaction, the organic solvents exemplified as the organic solvents used in the synthesis of polyamic acid (P) can be cited. The reaction temperature of the dehydration ring-closure reaction is preferably 0°C to 180°C, more preferably 10°C to 150°C. The reaction time is preferably 1.0 hour to 120 hours, more preferably 2.0 hour to 30 hours.

[0126] A reaction solution containing polyimide (P) is obtained in the described manner. The reaction solution can be directly used for the preparation of a liquid crystal alignment agent, or it can be used for the preparation of a liquid crystal alignment agent after removing a dehydrating agent and a dehydration ring-closure catalyst from the reaction solution, or it can be used for the preparation of a liquid crystal alignment agent after separating the polyimide (P), or it can be used for the preparation of a liquid crystal alignment agent after refining the separated polyimide (P). These refining operations can be carried out according to known methods. In addition, polyimide (P) can also be obtained by imidization of polyamic acid ester (P).

[0127] In addition, about the polyamide as polymer (P), polyamide-imide, polyurea and polyimide, also can be similarly with polyamic acid (P), polyamic acid ester (P) and polyimide (P), by using specific diamine as monomer to obtain.Specifically, polyamide can be obtained by making dicarboxylic acid derivatives and the method for reacting the diamine comprising specific diamine etc. to obtain.Polyamide-imide can be obtained by making tricarboxylic acid derivatives and the method for reacting the diamine comprising specific diamine etc. to obtain.In addition, polyurea can be obtained by making isocyanate compound and the method for reacting the polyamine comprising specific diamine etc. to obtain.Polyimide can be obtained by making dialdehyde compound and the method for reacting the diamine comprising specific diamine etc. to obtain.In each of the reactions, as specific diamine, the compound identical with the compound exemplified in the description of polyamic acid (P) can be used.

[0128] The solution viscosity of the polymer (P) contained in the liquid crystal aligning agent is preferably 10 mPa·s to 800 mPa·s when prepared as a solution having a concentration of 10% by mass, and more preferably 15 mPa·s to 500 mPa·s. In addition, the solution viscosity (mPa·s) is a value measured at 25°C using an E-type rotational viscometer on a 10% by mass polymer solution prepared in a good solvent (e.g., γ-butyrolactone, N-methyl-2-pyrrolidone, etc.) of the polymer.

[0129] The weight average molecular weight (Mw) of the polymer (P) as measured by gel permeation chromatography (GPC) in terms of polystyrene is preferably from 1,000 to 500,000, more preferably from 5,000 to 100,000. The molecular weight distribution (Mw / Mn), represented by the ratio of Mw to the number average molecular weight (Mn) in terms of polystyrene as measured by GPC, is preferably 15 or less, more preferably 10 or less.

[0130] From the viewpoint of obtaining a liquid crystal element having excellent liquid crystal orientation and voltage retention characteristics, high film strength and excellent reliability, the content ratio of the polymer (P) in the liquid crystal alignment agent is preferably set to 5% by mass or more, more preferably to 10% by mass or more, and further preferably to 20% by mass or more, relative to the total mass of the solid components contained in the liquid crystal alignment agent (the total mass of the components of the liquid crystal alignment agent other than the solvent).

[0131] [Other ingredients]

[0132] The liquid crystal aligning agent of the present disclosure may further contain components other than the polymer (P) (hereinafter also referred to as "other components"). Examples of other components include a polymer different from the polymer (P) (hereinafter also referred to as "polymer (Q)"), a crosslinking agent, and a solvent.

[0133] Polymer (Q)

[0134] Polymer (Q) is a polymer that does not contain the structural unit derived from specific diamine.The main skeleton of polymer (Q) is not particularly limited.As polymer (Q), for example, can be listed: polyamic acid, polyamic acid ester, polyimide, polyorganosiloxane, polyester, polyenamine, polyurea, polyamide, polyamideimide, polyimine, polybenzoxazole precursor, polybenzoxazole, cellulose derivative, polyacetal, addition polymer etc.As addition polymer, for example, can be listed: (meth) acrylic acid polymer, styrene polymer, maleimide polymer, (meth) acrylic acid-styrene copolymer, (meth) acrylic acid-maleimide copolymer, (meth) acrylic acid-styrene-maleimide copolymer and styrene-maleimide copolymer etc.

[0135] When used in combination with the polymer (P), the polymer (Q) is preferably at least one selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, polyorganosiloxane, and addition polymers in terms of exhibiting good liquid crystal orientation and voltage retention characteristics.

[0136] When the liquid crystal aligning agent contains a polymer (Q), the content of the polymer (Q) is preferably 30% by mass or more, more preferably 40% by mass or more, and further preferably 50% by mass or more, relative to the total amount of the polymer (P) and the polymer (Q). Furthermore, the content of the polymer (Q) is preferably 95% by mass or less, more preferably 90% by mass or less, and further preferably 80% by mass or less, relative to the total amount of the polymer (P) and the polymer (Q).

[0137] Cross-linking agent

[0138] The liquid crystal alignment agent of the present disclosure may also contain a cross-linking agent. By further containing a cross-linking agent, it is possible to achieve an improvement in the reliability of the liquid crystal element or a further reduction in the generation of AC residual images. As the cross-linking agent, the following compounds can be listed, i.e., compounds having two or more groups selected from the group consisting of a cyclic ether group, a cyclic thioether group, an isocyanate group, a protected isocyanate group, a hydroxymethyl group, a protected hydroxymethyl group, a hydroxyalkylamide group, a protected hydroxyalkylamide group, a cyclic carbonate group, a group containing a polymerizable carbon-carbon bond, a protected amino group, a silanol group, and an alkoxysilyl group in the molecule.

[0139] From the perspective of sufficiently improving the AC afterimage characteristics and reliability of the liquid crystal element, the number of crosslinkable groups contained in one molecule of the crosslinking agent is preferably 2 to 10, more preferably 2 to 6. Furthermore, the molecular weight of the crosslinking agent is preferably 100 to 1,000, more preferably 100 to 800, and even more preferably 100 to 700.

[0140] Specific examples of crosslinking agents include compounds having a cyclic ether group or a cyclic thioether group, such as ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, triglycidyl isocyanurate, glycerol polyglycidyl ether, pentaerythritol tetraglycidyl ether, 1,4-cyclohexanedimethanol diglycidyl ether, N,N',N',N'-tetraglycidyl glycoluril, 1,6-hexanediol diglycidyl ether, trimethylolpropane triglycidyl ether, 2,2-dibromocyanurate, Pentanediol diglycidyl ether, N,N,N',N'-tetraglycidyl-m-xylylenediamine, 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, N,N-diglycidyl-benzylamine, N,N-diglycidyl-aminomethylcyclohexane, N,N-diglycidyl-cyclohexylamine, epoxidation reaction products of 2,2'-diallylbisphenol A diallyl ether using hydrogen peroxide, etc.

[0141] Examples of the compound having an isocyanate group or a protected isocyanate group include tolylene diisocyanate, xylene diisocyanate, chlorophenylene diisocyanate, hexamethylene diisocyanate, tetramethylene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, or compounds in which the isocyanate groups of these compounds are protected with 3,6-dimethylpyrazole, methyl ethyl ketoxime, diethyl malonate, or ε-caprolactam; and compounds represented by the following formula (d1-1).

[0142] Examples of the compound having a hydroxymethyl group or a protected hydroxymethyl group include compounds represented by the following formula (d2-1) to formula (d2-5), and the like.

[0143] Examples of the compound having a hydroxyalkylamide group or a protected hydroxyalkylamide group include compounds represented by the following formula (d3-1) to formula (d3-8), and the like.

[0144] Examples of the compound having a cyclic carbonate group include compounds represented by the following formula (d4-1) and formula (d4-2).

[0145] Examples of compounds having a group containing a polymerizable carbon-carbon bond include compounds having a (meth)acryloyl group, a maleimide group, an alkenyl group, a vinylphenyl group, a vinyl ether group, or a 3-methylenetetrahydrofuran-2(3H)-one-5-yl group. Specific examples thereof include ethylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, pentaerythritol tri(meth)acrylate, and compounds represented by the following formulas (d5-1) to (d5-7), respectively.

[0146] Examples of the compound having a protected amino group include compounds represented by the following formula (d6-1) to formula (d6-5).

[0147] Examples of the compound having a silanol group or an alkoxysilane group include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropylmethyldimethoxysilane, 3-(meth)acryloxypropylmethyldiethoxysilane, and vinyltriethoxysilane.

[0148] [Chemistry 12]

[0149]

[0150] [Chemistry 13]

[0151]

[0152] (In formula (d2-4), Ac is an acetyl group)

[0153] [Chemistry 14]

[0154]

[0155] [Chemistry 15]

[0156]

[0157] [Chemistry 16]

[0158]

[0159] [Chemistry 17]

[0160]

[0161] In the case of making the liquid crystal alignment agent of the present disclosure contain a cross-linking agent, with respect to the viewpoint of improving the mechanical properties of the liquid crystal alignment film and realizing the improvement of the reliability of the liquid crystal element or the further reduction of the AC residual image, the content of the cross-linking agent is preferably 0.5 parts by mass or more relative to the total amount of the polymer components contained in the liquid crystal alignment agent (that is, the total amount of polymer (P) and polymer (Q)) 100 parts by mass. With respect to the above viewpoint, the content of the cross-linking agent is more preferably 1 part by mass or more, and further preferably 2 parts by mass or more, relative to the total amount of 100 parts by mass of the polymer components. In addition, with respect to the viewpoint of obtaining a liquid crystal element with good liquid crystal orientation and electrical properties, and the viewpoint of making the storage stability of the liquid crystal alignment agent good, the content of the cross-linking agent is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and further preferably 10 parts by mass or less relative to the total amount of 100 parts by mass of the polymer components.

[0162] Solvent

[0163] The liquid crystal aligning agent of the present disclosure is prepared in the form of a liquid composition, and the liquid composition is preferably obtained by dispersing or dissolving a polymer (P) and optionally used components in an appropriate solvent.

[0164] Examples of the organic solvent include N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butyrolactam, N,N-dimethylformamide, N,N-dimethylacetamide, 4-hydroxy-4-methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol n-propyl ether, ethylene glycol isopropyl ether, ethylene glycol n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diisobutyl ketone, isoamyl propionate, isoamyl isobutyrate, diisoamyl ether, ethylene carbonate, and propylene carbonate.

[0165] Other components, in addition to those mentioned above, include antioxidants, metal chelate compounds, curing accelerators, surfactants, fillers, dispersants, photosensitizers, acid generators, base generators, and free radical generators. The proportions of these components can be appropriately selected for each compound within a range that does not impair the effects of the present disclosure.

[0166] The solid content concentration in the liquid crystal alignment agent (the ratio of the total mass of the components of the liquid crystal alignment agent other than the solvent to the total mass of the liquid crystal alignment agent) can be appropriately selected considering viscosity, volatility, etc., preferably in the range of 1% by mass to 10% by mass. That is, the liquid crystal alignment agent is applied to the substrate surface as described later, preferably heated, thereby forming a coating film as a liquid crystal alignment film or a coating film as a liquid crystal alignment film. At this time, when the solid content concentration is 1% by mass or more, the film thickness of the coating film can be fully ensured, and there is a tendency to easily obtain a good liquid crystal alignment film. When the solid content concentration is 10% by mass or less, the film thickness of the coating film will not become too large. In addition, the viscosity of the liquid crystal alignment agent can be suppressed from increasing, and there is a tendency to make the coating property good.

[0167] The range of particularly preferred solid content concentration varies depending on the purpose of the liquid crystal aligning agent or the method used when applying the liquid crystal aligning agent to the substrate. For example, with respect to the liquid crystal aligning agent for liquid crystal display elements, when applied to the substrate by a spinner method, the solid content concentration (the ratio of the total mass of all components in the liquid crystal aligning agent except the solvent to the total mass of the liquid crystal aligning agent) is particularly preferably in the range of 1.5% by mass to 4.5% by mass. In the case of using a printing method, it is particularly preferred to set the solid content concentration to the range of 3% by mass to 9% by mass, thereby setting the solution viscosity to the range of 12mPa·s to 50mPa·s. In the case of using an inkjet method, it is particularly preferred to set the solid content concentration to the range of 1% by mass to 5% by mass, thereby setting the solution viscosity to the range of 3mPa·s to 15mPa·s. The temperature when preparing the liquid crystal aligning agent is preferably 10°C to 50°C, more preferably 20°C to 30°C. In addition, regarding the liquid crystal aligning agent for retardation film, from the viewpoint of making the coating property of the liquid crystal aligning agent and the film thickness of the formed coating film appropriate, the solid content concentration of the liquid crystal aligning agent is preferably in the range of 0.2% by mass to 10% by mass, and more preferably in the range of 3% by mass to 10% by mass.

[0168] Liquid crystal alignment film and liquid crystal element

[0169] The liquid crystal alignment film of the present invention can be formed by a liquid crystal alignment agent prepared in the manner described. In addition, the liquid crystal element of the present invention has a liquid crystal alignment film formed using the liquid crystal alignment agent described in the above. The action mode of the liquid crystal in the liquid crystal element is not particularly limited, for example, it can be applied to twisted nematic (TN) type, super twisted nematic (STN) type, vertical alignment (VA) type (including vertical alignment-multi-domain vertical alignment (VA-MVA) type, vertical alignment-patterned vertical alignment (VA-PVA) type, etc.), in-plane switching (IPS) type, fringe field switching (FFS) type, optically compensated bend (OCB) type, polymer stabilized alignment (PSA) type and other modes. The liquid crystal element can be produced, for example, by a method including the following steps 1 to 3. In step 1, the substrate used varies depending on the desired operation mode. Steps 2 and 3 are common to each operation mode.

[0170] <Step 1: Coating Film Formation>

[0171] First, a liquid crystal alignment agent is applied to a substrate, and the coated surface is preferably heated to form a coating film on the substrate. As a substrate, for example, a transparent substrate comprising the following materials can be used: glass such as float glass and soda glass; resins such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, polycarbonate, and poly(alicyclic olefin). In the case of 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, in the case of 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. As a transparent conductive film, a NESA film (registered trademark of PPG Corporation, USA) containing tin oxide (SnO2) and an indium tin oxide (ITO) film containing indium oxide-tin oxide (In2O3-SnO2) can be used. The liquid crystal alignment agent is preferably applied to the substrate surface by offset printing, flexographic printing, spin coating, roll coater coating, or inkjet printing. The liquid crystal alignment agent disclosed herein can easily form a uniform film even by inkjet coating, and is therefore suitable for inkjet coating.

[0172] 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. Thereafter, a calcination (post-baking) process is performed for the purpose of removing the solvent in the applied liquid crystal alignment agent. The calcination temperature (post-baking temperature) at this time is preferably 80°C to 250°C, more preferably 80°C to 200°C. The post-baking time is preferably 5 minutes to 200 minutes. The thickness of the film formed in this way is preferably 0.001 μm to 1 μm.

[0173] <Step 2: Orientation Treatment>

[0174] In the case of manufacturing TN type, STN type, IPS type or FFS type liquid crystal elements, a process (orientation treatment) for 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, the following treatments can be used: a friction treatment in which a roller wound with a cloth containing fibers such as nylon, rayon, and cotton is rubbed in a certain direction against the coating film formed on the substrate; a light orientation treatment in which the coating film formed on the substrate is irradiated with light and the coating film is imparted with liquid crystal orientation ability. On the other hand, in the case of manufacturing a vertically aligned (VA) type liquid crystal element, the coating film formed in the process 1 can be directly used as a liquid crystal alignment film. In addition, in order to further improve the liquid crystal orientation ability, an orientation treatment can also be applied to the coating film. The liquid crystal alignment film preferred for a vertically aligned liquid crystal element is also preferred for a PSA type liquid crystal element.

[0175] In the photo-alignment treatment, light irradiation 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 the 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, irradiation can be performed from a direction perpendicular to the substrate surface, from an oblique direction, or a combination of these directions. The irradiation direction in the case of non-polarized radiation is set to an oblique direction.

[0176] 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 to the substrate surface is preferably 400 J / m 2 ~50,000J / m 2 , more preferably 1,000 J / m 2 ~20,000J / m 2 After 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.

[0177] <Step 3: Liquid Crystal Cell Construction>

[0178] Prepare two substrates with liquid crystal alignment films formed in the manner described above, and manufacture a liquid crystal cell by configuring a liquid crystal adjacent to the liquid crystal alignment film between the two substrates. When manufacturing a liquid crystal cell, for example, the following method can be cited: two substrates are arranged oppositely across a gap in a manner in which the liquid crystal alignment films face each other, the peripheral portions of the two substrates are bonded together using a sealant, and a method of injecting a filling liquid crystal into the cell gap surrounded by the substrate surface and the sealant and sealing the injection hole; a method based on a liquid crystal droplet (One Drop Fill, ODF) method, etc. As a sealant, an epoxy resin containing a hardener and an alumina ball as a spacer can be used. As a liquid crystal, nematic liquid crystal and smectic liquid crystal can be listed, wherein nematic liquid crystal is preferably used. In the PSA mode, the following treatment is performed: a liquid crystal and a photopolymerizable compound are arranged between two substrates, thereby constructing a liquid crystal cell, and after constructing the liquid crystal cell, the liquid crystal cell is irradiated with light while a voltage is applied between the conductive films possessed by a pair of substrates.

[0179] Next, for each mode of liquid crystal cell, a polarizing plate is attached to the outer surface of the liquid crystal cell as needed to produce a liquid crystal element. Examples of polarizing plates include those made by sandwiching a polarizing film called "H film" made by stretching and aligning polyvinyl alcohol while allowing it to absorb iodine, between cellulose acetate protective films, or those consisting solely of the H film.

[0180] The liquid crystal element disclosed herein can be effectively applied to various applications. Specifically, it can be applied to various display 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 to light-adjusting films and retardation films.

[0181] As described above, it is believed that the polymer (P) has a multi-point hydrogen bonding structure in the main chain, which facilitates intermolecular interactions between the polymers. Furthermore, the chain structure derived from the multi-point hydrogen bonding structure exhibits excellent thermal rearrangement and stretchability. Such polymer (P) can also be used in optical films, flexible substrates, photosensitive resin compositions, surface protective films, interlayer insulating films, and the like.

[0182] The above description discloses the following aspects [1] to

[10] .

[0183] [1] A liquid crystal aligning agent comprising a polymer containing a structural unit derived from the diamine represented by the above formula (0).

[0184] [2] The liquid crystal aligning agent according to [1], wherein X in the formula (0) 1 and X 2 are independently a single bond, a divalent hydrocarbon group having 1 to 12 carbon atoms, an oxygen atom, a sulfur atom, -CO-, -SO2-, -NR 6 -, -C=N- or any methylene group in a divalent hydrocarbon group having 2 to 12 carbon atoms, such as an oxygen atom, a sulfur atom, -CO-, -SO2-, -NR 6 - or -C=N-substituted divalent group (wherein, R 6 is a hydrogen atom or a monovalent organic group).

[0185] [3] The liquid crystal aligning agent according to [1] or [2], wherein Z in the formula (0) 1 It is a monovalent aliphatic hydrocarbon group having 1 to 6 carbon atoms.

[0186] [4] The liquid crystal aligning agent according to any one of [1] to [3], wherein, when p in the formula (0) is 1 or more, R 1 is an alkyl group having 1 to 3 carbon atoms, and when q in the formula (0) is 1 or more, R 2 It is an alkyl group having 1 to 3 carbon atoms.

[0187] [5] The liquid crystal alignment agent according to any one of [1] to [4], wherein the polymer is at least one selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, polyamide, polyamideimide, polyurea, and polyimide.

[0188] [6] The liquid crystal aligning agent according to any one of [1] to [5], further comprising a polymer that does not contain a structural unit derived from the diamine represented by the formula (0).

[0189] [7] The liquid crystal aligning agent according to any one of [1] to [6], wherein the diamine represented by the formula (0) is represented by the formula (1).

[0190] [8] A liquid crystal alignment film formed using the liquid crystal alignment agent according to any one of [1] to [7].

[0191] [9] A liquid crystal element comprising the liquid crystal alignment film according to [8].

[0192]

[10] A polymer comprising a structural unit derived from the diamine represented by the formula (0).

[0193]

[11] A diamine represented by the above formula (0).

[0194] [Example]

[0195] Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

[0196] The structures and abbreviations of the main compounds used in the following examples are as follows.

[0197] [Tetracarboxylic dianhydride]

[0198] Compounds (TA-1) to (TA-5): Compounds represented by the following formulas (TA-1) to (TA-5)

[0199] [Chemistry 18]

[0200]

[0201] [Diamine]

[0202] Compounds (DA-1) to (DA-8): Compounds represented by the following formulas (DA-1) to (DA-8)

[0203] [Chemistry 19]

[0204]

[0205] Compounds (DB-1) to (DB-14): Compounds represented by the following formulas (DB-1) to (DB-14)

[0206] [Chemistry 20]

[0207]

[0208] [additive]

[0209] Compounds (AD-1) to (AD-3): Compounds represented by the following formulas (AD-1) to (AD-3)

[0210] [Chemistry 21]

[0211]

[0212] [Solvent]

[0213] NMP: N-Methyl-2-Pyrrolidone

[0214] GBL: Gamma-Butyrolactone

[0215] BC: Butyl Cellosolve

[0216] DAA: Diacetone Alcohol

[0217] THF: Tetrahydrofuran

[0218] <Synthesis and Evaluation of Compounds>

[0219] [Synthesis example 1]

[0220] The diamine (compound (DA-1)) represented by the formula (DA-1) was synthesized according to the following synthesis scheme.

[0221] Oxalyl chloride (30.0 mmol) and THF (40 mL) were placed in a three-necked flask including a reflux tube, a thermometer, and a nitrogen inlet tube. Under a nitrogen stream, a solution of 2-methyl-4-nitroaniline (63.0 mmol) dissolved in THF (40 mL) was added dropwise over 5 minutes while stirring at 0°C, and then stirred at 0°C for 1 hour. After the reaction was completed, water (20 mL) was added and stirred to precipitate a light yellow solid. The obtained precipitate was filtered, washed with a mixed solvent of water / isopropanol = 1 / 1 (v / v), and dried under reduced pressure to obtain an intermediate represented by the following formula (DA-1-1) with a yield of 92%.

[0222] Subsequently, the intermediate (DA-1-1) (15.0 mmol), N,N-dimethylaminopyridine (7.5 mmol), and NMP (40 mL) were placed in a three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen inlet tube. Under a nitrogen stream, di-tert-butyl dicarbonate (33.0 mmol) was added dropwise over 5 minutes while stirring at room temperature. The mixture was then stirred at 50°C for 1 hour. After the reaction was completed, the reaction solution was added to water and stirred to precipitate a yellow solid. The precipitate was filtered, washed with water, and dried under reduced pressure to obtain the intermediate represented by the following formula (DA-1-2) with a yield of 93%.

[0223] Furthermore, an intermediate (DA-1-2) (10.0 mmol), metallic zinc (200 mmol), ammonium chloride (100 mmol), THF (30 mL) and ethanol (10 mL) were placed in a three-necked flask including a reflux tube, a thermometer and a nitrogen inlet tube, and water (10 mL) was added dropwise at 0°C for 5 minutes while stirring under a nitrogen stream, and then stirred at 0°C for 2 hours. After the reaction, the reaction solution was diluted with THF, saturated sodium bicarbonate aqueous solution was added, and diatomaceous earth filtration was performed. The organic phase of the filtrate was separated and washed with saturated brine, dried by adding anhydrous sodium sulfate, filtered, and concentrated under reduced pressure. The obtained residue was dissolved in THF, added dropwise to water for reprecipitation, filtered, and dried under reduced pressure to obtain compound (DA-1) with a yield of 89%.

[0224] Compound (DA-1) 1 H-NMR spectroscopy (dimethyl sulfoxide (DMSO)-d6, 400 MHz) and 13 The measurement results of C-NMR spectrum (DMSO-d6, 75 MHz) are shown in Figure 1 and Figure 2 middle.

[0225] [Chemistry 22]

[0226]

[0227] [Synthesis example 2]

[0228] The diamine (compound (DA-2)) represented by the formula (DA-2) was synthesized according to the following synthesis scheme.

[0229] In a three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen inlet tube, 4-nitrophenethylamine hydrochloride (20.5 mmol), sulfonamide (10.0 mmol), N,N-diisopropylethylamine (21.0 mmol), and pyridine (30 mL) were placed. The mixture was stirred under a nitrogen stream while refluxed for 12 hours. After the reaction, water (50 mL) and hexane (50 mL) were added and stirred for 1 hour, resulting in the precipitation of a pale yellow solid. The precipitate was filtered, washed with water, hexane, and ethanol, and dried under reduced pressure to obtain the intermediate represented by the following formula (DA-2-1) in a 75% yield.

[0230] Then, in a three-necked flask including a reflux tube, a thermometer and a nitrogen inlet tube, the intermediate (DA-2-1) (5.0 mmol), N, N-dimethylaminopyridine (0.5 mmol) and THF (20 mL) were placed. Under a nitrogen stream, di-tert-butyl dicarbonate (11.0 mmol) was added dropwise over 5 minutes while stirring at room temperature, and then stirred at 50 ° C for 5 hours. After the reaction was completed, the reaction solution was added to water (80 mL) and stirred for 1 hour to precipitate a white solid. The obtained precipitate was filtered, washed with water and ethanol, and dried under reduced pressure to obtain the intermediate represented by the following formula (DA-2-2) with a yield of 93%.

[0231] Furthermore, an intermediate (DA-2-2) (4.0 mmol), metallic zinc (80 mmol), ammonium chloride (16 mmol), THF (20 mL) and ethanol (20 mL) were placed in a three-necked flask including a reflux tube, a thermometer and a nitrogen inlet tube. Under a nitrogen stream, water (8 mL) was added dropwise while stirring at room temperature for 5 minutes, and then stirred at 60 ° C for 2 hours. After the reaction is completed, the reaction solution is filtered with diatomaceous earth, and the filtrate is concentrated under reduced pressure. The residue is extracted with ethyl acetate, and the organic phase is separated and washed with water, a saturated aqueous sodium bicarbonate solution, and saturated brine. Anhydrous sodium sulfate is added to the obtained organic phase and dried, filtered, and concentrated under reduced pressure to precipitate a white solid. The obtained solid is slurried and washed with ethanol, filtered, and dried under reduced pressure to obtain compound (DA-2) with a yield of 79%.

[0232] Compound (DA-2) 1 H-NMR spectrum (CDCl3, 400MHz) and 13 The measurement results of C-NMR spectrum (CDCl3, 75 MHz) are shown in Figure 3 and Figure 4 middle.

[0233] [Chemistry 23]

[0234]

[0235] [Synthesis example 3]

[0236] The diamine represented by the formula (DA-3) (compound (DA-3)) was synthesized according to the following synthesis scheme.

[0237] 3-(4-nitrophenyl)propionic acid (21.0 mmol), N,N-dimethylformamide (0.5 mmol), and dichloromethane (25 mL) were placed in a three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen inlet tube. Under a nitrogen stream, thionyl chloride (30.0 mmol) was added dropwise over 5 minutes while stirring at room temperature, and then stirred at 40°C for 3 hours. The resulting mixture was concentrated under reduced pressure and diluted with THF (10 mL) to prepare a solution of the acid chloride intermediate. Separately, hydrazine monohydrate (10.0 mmol), triethylamine (30.0 mmol), and THF (25 mL) were placed in a three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen inlet tube. Under a nitrogen stream, the solution of the acid chloride intermediate was added dropwise over 5 minutes while stirring at room temperature, and then stirred for 1 hour. After the reaction was completed, the reaction solution was added dropwise to water (200 mL) to precipitate a solid. The obtained precipitate was filtered, washed with water and THF, and dried under reduced pressure to obtain an intermediate represented by the following formula (DA-3-1) at a yield of 86%.

[0238] Then, in a three-necked flask including a reflux tube, a thermometer and a nitrogen inlet tube, the intermediate (DA-3-1) (10.0 mmol), N, N-dimethylaminopyridine (1.0 mmol) and NMP (25 mL) were placed. Under a nitrogen stream, di-tert-butyl dicarbonate (22.0 mmol) was added dropwise over 5 minutes while stirring at room temperature, and then stirred for 3 hours. After the reaction was completed, hexane (100 mL) and isopropanol (10 mL) were added and stirred for 1 hour to precipitate a solid. The obtained precipitate was filtered and dried under reduced pressure to obtain the intermediate represented by the following formula (DA-3-2) with a yield of 72%.

[0239] Furthermore, an intermediate (DA-3-2) (5.0 mmol), metallic zinc (100 mmol), ammonium chloride (50 mmol), THF (15 mL) and ethanol (5 mL) were placed in a three-necked flask including a reflux tube, a thermometer and a nitrogen inlet tube. Under a nitrogen stream, water (5 mL) was added dropwise while stirring in an ice bath for 5 minutes, and then stirred at room temperature for 2 hours. After the reaction was completed, the reaction solution was filtered through diatomaceous earth, and the filtrate was concentrated under reduced pressure. The residue was extracted with ethyl acetate, and the organic phase was separated and washed with water. Anhydrous sodium sulfate was added to the obtained organic phase and dried, filtered, and concentrated under reduced pressure to precipitate a white solid. The obtained solid was dissolved in THF, added dropwise to ethanol and reprecipitated, filtered, and dried under reduced pressure to obtain compound (DA-3) with a yield of 64%.

[0240] Compound (DA-3) 1H-NMR spectrum (DMSO-d6, 400 MHz) and 13 The measurement results of C-NMR spectra (DMSO-d6, 75 MHz) are shown in Figure 5 and Figure 6 middle.

[0241] [Chemistry 24]

[0242]

[0243] [Synthesis Example 4]

[0244] The diamine represented by the formula (DA-4) (compound (DA-4)) was synthesized according to the following synthesis scheme.

[0245] 2-(4-nitrophenoxy)acetic acid (63.0 mmol), N,N-dimethylformamide (1.5 mmol), and dichloromethane (65 mL) were placed in a three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen inlet tube. Under a nitrogen stream, thionyl chloride (90.0 mmol) was added dropwise over 5 minutes while stirring at room temperature, and then stirred at 40°C for 4 hours. The resulting mixture was concentrated under reduced pressure and diluted with THF (20 mL) to prepare a solution of the acid chloride intermediate. Separately, hydrazine monohydrate (30.0 mmol), pyridine (90.0 mmol), and THF (65 mL) were placed in a three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen inlet tube. Under a nitrogen stream, the solution of the acid chloride intermediate was added dropwise over 5 minutes while stirring at room temperature, and then stirred for 1 hour. After the reaction was completed, the reaction solution was added dropwise to water (400 mL) to precipitate a solid. The obtained precipitate was filtered, washed with water, isopropyl alcohol, and THF, and dried under reduced pressure to obtain an intermediate represented by the following formula (DA-4-1) at a yield of 47%.

[0246] Then, in a three-necked flask including a reflux tube, a thermometer and a nitrogen inlet tube, the intermediate (DA-4-1) (10.0 mmol), N,N-dimethylaminopyridine (1.0 mmol) and NMP (25 mL) were placed. Under a nitrogen stream, di-tert-butyl dicarbonate (22.0 mmol) was added dropwise over 5 minutes while stirring at room temperature, and then stirred at 50°C for 8 hours. After the reaction was completed, the reaction solution was added dropwise to water for reprecipitation and filtered. The obtained solid was slurried and washed with isopropanol at 50°C, cooled to room temperature, filtered, and dried under reduced pressure to obtain the intermediate represented by the following formula (DA-4-2) with a yield of 79%.

[0247] Furthermore, in a three-necked flask including a reflux tube, a thermometer and a nitrogen inlet tube, an intermediate (DA-4-2) (5.0 mmol), metallic zinc (100 mmol), ammonium chloride (50 mmol), THF (40 mL) and ethanol (10 mL) were placed, and water (5 mL) was added dropwise while stirring in an ice bath under a nitrogen stream for 5 minutes, and then stirred at room temperature for 2 hours. After the reaction was completed, the reaction solution was filtered through diatomaceous earth, and the filtrate was concentrated under reduced pressure. The residue was extracted with ethyl acetate, and the organic phase was separated and washed with water. Anhydrous sodium sulfate was added to the obtained organic phase and dried, filtered, and concentrated under reduced pressure to precipitate a white solid. The obtained solid was dissolved in THF, added dropwise to ethanol and reprecipitated, filtered, and dried under reduced pressure to obtain compound (DA-4) with a yield of 32%.

[0248] Compound (DA-4) 1 H-NMR spectrum (DMSO-d6, 400 MHz) and 13 The measurement results of C-NMR spectra (DMSO-d6, 75 MHz) are shown in Figure 7 and Figure 8 middle.

[0249] [Chemistry 25]

[0250]

[0251] [Synthesis example 5]

[0252] The diamine (compound (DA-5)) represented by the formula (DA-5) was synthesized according to the following synthesis scheme.

[0253] [Chemistry 26]

[0254]

[0255] [Synthesis example 6]

[0256] The diamine represented by the formula (DA-6) (compound (DA-6)) was synthesized according to the following synthesis scheme.

[0257] After adding chloroform (60 mL) and hydrazine monohydrate (2.43 mL, 50 mmol) to a 300 mL eggplant flask, the mixture was cooled to 0°C and 4-bromobutyryl chloride (5.76 mL, 50 mmol) was added little by little. After stirring at 0°C for 30 minutes, a solution of sodium carbonate (5.30 g, 50 mmol) dissolved in 40 mL of distilled water was added little by little, and 4-bromobutyryl chloride (6.34 mL, 55 mmol) was added little by little, and the mixture was stirred at room temperature for 3 hours. After the reaction, the precipitate was filtered using a Kiriyama funnel and washed with distilled water and chloroform to obtain 17.5 g of wet crystals. The precipitate was dissolved in 150 mL of methanol at 60°C and allowed to stand overnight. The recrystallized product was filtered, washed with methanol, and dried to obtain 1.23 g (3.73 mmol, 7.5% yield) of an intermediate represented by the following formula (DA-6-1) as a white powder.

[0258] In a 200 mL eggplant-shaped flask, the intermediate (DA-6-1) (1.23 g, 3.73 mmol), THF (37.3 mL), N,N-dimethylaminopyridine (228 mg, 1.86 mmol), and di-tert-butyl dicarbonate (4.07 g, 18.6 mmol) were mixed and stirred at 50°C for 2 days. After the reaction was completed, 1-methylpiperazine (2.07 mL, 18.6 mmol) was added, and after stirring at room temperature for 1 day, 100 mL of ethyl acetate was added, and extraction and washing were performed three times with 100 mL of distilled water. The organic layer was dried over magnesium sulfate, filtered, and concentrated to obtain 1.41 g (2.66 mmol, 71.3% yield) of the intermediate represented by the following formula (DA-6-2) as a yellow liquid.

[0259] To a 200 mL eggplant-shaped flask, intermediate (DA-6-2) (1.41 g, 2.66 mmol), dimethylacetamide (DMAc) (20 mL), 4-nitrophenol (777 mg, 5.58 mmol), and potassium carbonate (919 mg, 6.65 mmol) were added and stirred at 60°C for 8 hours. After the reaction was completed, 100 mL of ethyl acetate was added, and the mixture was extracted and washed once with 100 mL of distilled water, twice with 100 mL of ammonium chloride aqueous solution and twice with 100 mL of sodium bicarbonate aqueous solution, and finally twice with distilled water. The organic layer was dried over magnesium sulfate, filtered, and concentrated to obtain 1.29 g (1.99 mmol, 75.0% yield) of the intermediate represented by the following formula (DA-6-3) as a yellow liquid.

[0260] In a 200 mL eggplant flask, the intermediate (DA-6-3) (1.29 g, 1.99 mmol), zinc (2.61 g, 39.9 mmol), ammonium chloride (1.07 g, 19.9 mmol), THF (30 mL), and ethanol (10 mL) were mixed and cooled to 0°C. After distilled water (1.02 g, 56.9 mmol) was added dropwise, the mixture was stirred at room temperature for 2 days. After the reaction was completed, zinc was removed by filtration through diatomaceous earth, and after rinsing with THF, 100 mL of ethyl acetate was added, and extraction and washing were performed three times with 100 mL of distilled water. The organic layer was dried over magnesium sulfate, filtered, and concentrated. The obtained yellow viscous liquid was purified by column chromatography using a developing solvent of hexane / ethyl acetate = 50 / 50. The solution was concentrated to obtain 209 mg (356 μmol, 17.9% yield) of compound (DA-6) as a yellow viscous liquid.

[0261] Compound (DA-6) 1 H-NMR spectrum (CDCl3, 400MHz) and 13 The measurement results of C-NMR spectrum (CDCl3, 75 MHz) are shown in Figure 9 and Figure 10 middle.

[0262] [Chemistry 27]

[0263]

[0264] [Synthesis Example 7]

[0265] The diamine represented by the formula (DA-7) (compound (DA-7)) was synthesized according to the following synthesis scheme.

[0266] [Chemistry 28]

[0267]

[0268] [Synthesis example 8]

[0269] The diamine (compound (DA-8)) represented by the formula (DA-8) was synthesized according to the following synthesis scheme.

[0270] [Chemistry 29]

[0271]

[0272] [Evaluation of hydrogen bonding properties]

[0273] Using Gaussian 16 Rev B.01, a quantum chemical calculation program manufactured by Gaussian, the charge density of each atom was calculated by density functional theory, and hydrogen bonding properties were evaluated. In the calculation, the density functional theory was set to M06-2X, the basis function was set to def2-TZVPP, and structure optimization and charge density analysis based on the charge model 5 (CM5) were performed. For the model compounds with hydrogen bonding groups represented by the following formulas (ne-1) to (ne-8) and (nc-1) to (nc-4), the charge density of the hydrogen bond donor (hydrogen atom) and the hydrogen bond acceptor (oxygen atom) are summarized in Table 1.

[0274] It is believed that when the positive charge of the hydrogen bond donor is large and the negative charge of the hydrogen bond acceptor is large, the interaction between the molecules becomes greater. In particular, when the polymer is a polyimide or polyamic acid, it is ideal that the absolute value of the charge density of the hydrogen bond donor or hydrogen bond acceptor contained in the groups introduced into the polymer independently of the amide or imide groups is greater than the absolute value of the charge density of the hydrogen bond donor (amide group = +0.316) or hydrogen bond acceptor (imide group = -0.327) that is abundant in the polymer. Calculations for N-methylsuccinimide, a model compound for polyimides, show that the charge density of the oxygen atom of the imide group is -0.327.

[0275] In the case of containing a hydrogen bond donor with a charge density greater than +0.320 and a hydrogen bond acceptor with a charge density less than -0.330, the hydrogen bonding property was evaluated as good. Consequently, compounds (NC-1) to (NC-4), which only contain structures in which groups capable of hydrogen bond donors and groups capable of hydrogen bond acceptors are alternately bonded, have poor hydrogen bonding properties. In contrast, compounds (NE-1) to (NE-8), which contain structures in which two groups capable of hydrogen bond donors or groups capable of hydrogen bond acceptors are consecutively bonded, all have good hydrogen bonding properties.

[0276] Furthermore, it is believed that when groups capable of hydrogen bond donors or hydrogen bond acceptors are continuous, the continuous hydrogen bonding sites will influence each other, resulting in a synergistic effect that increases the strength of each hydrogen bond. Therefore, the actual hydrogen bonding capacity may be even greater than predicted based on the charge density.

[0277] [Chemistry 30]

[0278]

[0279] [Table 1]

[0280]

[0281] Regarding the numerical values ​​in Table 1, values ​​having a charge density greater than +0.320 and values ​​having a charge density less than −0.330 are underlined.

[0282] <Synthesis and Evaluation of Polymers>

[0283] Polymers were synthesized in the following Synthesis Examples 9 to 41. In the following examples, the imidization ratio of the polyimide in the polymer solution was measured by the following method.

[0284] [Imidization ratio of polyimide]

[0285] The polyimide solution was poured into pure water, the obtained precipitate was fully dried under reduced pressure at room temperature, and then dissolved in deuterated dimethyl sulfoxide. 1 H-NMR determination. 1 The imidization rate [%] was determined by H-NMR spectroscopy (400 MHz) using the following formula (1).

[0286] Imidization rate [%] = (1-α × A1 / A2) × 100 (1)

[0287] (In formula (1), A1 is the peak area of ​​protons derived from the amide group of the amic acid appearing at a chemical shift of around 10 ppm; A2 is the peak area of ​​protons derived from the aromatic group appearing at a chemical shift of around 6 to 9 ppm; α is the ratio of the number of protons of the aromatic group to one proton of the amide group of the amic acid in the polymer precursor (polyamic acid))

[0288] [Synthesis Example 9]

[0289] 40 parts by mole of compound (DA-1), 30 parts by mole of compound (DB-5), and 30 parts by mole of compound (DB-7) were dissolved in N-methyl-2-pyrrolidone (NMP), and 0.95 molar equivalent of tetracarboxylic dianhydride (compound (TA-2)) relative to the total amount of diamines was added. The mixture was reacted at room temperature for 6 hours to obtain a 15% by mass solution of a polyamic acid having a partial structure represented by the following formula (PA-1) (hereinafter referred to as polymer (PA-1)).

[0290] [Chemistry 31]

[0291]

[0292] [Synthesis Example 10 to Synthesis Example 35]

[0293] Except that the types and molar ratios of tetracarboxylic dianhydride and diamine were changed as described in Table 2 below, the same procedures as in Synthesis Example 9 were carried out to obtain polymers (PA-2) to (PA-22) and polymers (PA-C1) to (PA-C5) as polyamic acids, respectively.

[0294] [Synthesis Example 36]

[0295] Compound (DA-2) was dissolved in NMP, and 0.95 molar equivalents of tetracarboxylic dianhydride (compound (TA-2)) was added relative to the total amount of diamines, and the reaction was carried out at room temperature for 6 hours to obtain a solution of polyamic acid. 1-Methylpiperidine and acetic anhydride were added as dehydrating agents relative to the carboxyl group of polyamic acid in an amount of 0.50 molar equivalents, respectively, to the obtained solution, and heated with stirring at 60°C for 3 hours. For the obtained solution, reduced pressure concentration and dilution with NMP were repeated to obtain a 15% by mass solution of a polyimide having a partial structure represented by the following formula (PI-1) (set to polymer (PI-1)). The imidization rate of polymer (PI-1) was 50%.

[0296] [Chemistry 32]

[0297]

[0298] [Synthesis Example 37 to Synthesis Example 41]

[0299] Except for changing the types and molar ratios of tetracarboxylic dianhydride and diamine as described in Table 2 below, the same operation as in Synthesis Example 36 was carried out to obtain polymers (PI-2) to (PI-4) and polymers (PI-C1) to (PI-C2) as polyimides.

[0300] [Table 2]

[0301]

[0302] Regarding tetracarboxylic dianhydride, the numerical values ​​in Table 2 represent the usage ratio (mol %) of each compound relative to the total amount (100 mol %) of tetracarboxylic dianhydride used in the synthesis. Regarding diamine, the numerical values ​​in Table 2 represent the usage ratio (mol %) of each compound relative to the total amount (100 mol %) of diamine used in the synthesis.

[0303] <Preparation and Evaluation of Liquid Crystal Alignment Agents>

[0304] [Example 1: Photo-aligned FFS-type liquid crystal display element]

[0305] (1) Preparation of liquid crystal alignment agent

[0306] The polymer components (solids content conversion: 40 parts by mass of polymer (PA-1), 60 parts by mass of polymer (PA-10)), 10 parts by mass of compound (AD-1), and 1 part by mass of compound (AD-3) were diluted with NMP and BC to obtain a solution having a solid content concentration of 4.0% and a solvent composition ratio of NMP:BC = 60:40 (mass ratio). This solution was filtered through a filter with a pore size of 0.2 μm to prepare a liquid crystal aligning agent (AL-1).

[0307] (2) Formation of liquid crystal alignment film based on photo-alignment method

[0308] The liquid crystal alignment agent (AL-1) prepared in (1) was applied to each surface of a glass substrate having a flat electrode, an insulating layer, and a comb-shaped electrode laminated sequentially on one side and an opposing glass substrate having no electrode using a spin coater. The coating was heated on an 80°C hot plate for 1 minute and then heated in a 230°C oven purged with nitrogen for 30 minutes to form a coating film having an average film thickness of 100 nm. The coating film surface was irradiated with 3,000 J / m2 of ultraviolet rays containing linearly polarized 254 nm light from the substrate normal direction using a Hg-Xe lamp. 2 The coating film subjected to the photo-alignment treatment was heated for 30 minutes in an oven at 230° C. in which the interior of the chamber was purged with nitrogen to perform heat treatment (post-baking) to form a liquid crystal alignment film.

[0309] (3) Manufacturing of FFS type liquid crystal display elements

[0310] A liquid crystal injection port is left on the periphery of the surface with a liquid crystal orientation film of one of the substrates prepared in (2). After applying an epoxy resin adhesive containing aluminum oxide balls with a diameter of 3.5 μm using a dispenser, the surfaces of a pair of substrates with liquid crystal orientation films are made to face each other and pressed together in such a way that the orientation processing directions of each substrate become antiparallel. The adhesive is thermally cured at 150°C for 1 hour. Subsequently, a negative nematic liquid crystal (MLC-6608 manufactured by Merck) is filled into the gap between the substrates from the liquid crystal injection port, and the liquid crystal injection port is sealed with an epoxy adhesive. Furthermore, in order to remove the flow orientation during liquid crystal injection, the liquid crystal is heated at 120°C and then slowly cooled to room temperature. Next, polarizing plates are attached to both outer surfaces of the substrate to manufacture an FFS type liquid crystal display element.

[0311] (4) Evaluation of mechanical properties (friction resistance)

[0312] A spin coater was used to apply the liquid crystal alignment agent (AL-1) prepared in (1), and after heating on a hot plate at 80°C for 1 minute, the liquid crystal alignment agent (AL-1) was heated in an oven at 230°C in which nitrogen was replaced in the reservoir for 30 minutes to form a coating with an average film thickness of 100 nm, and a haze meter was used to measure the haze value of the coating. Subsequently, the coating was subjected to 5 friction treatments using a friction machine having a roller wound with cotton cloth, a roller speed of 1000 rpm, a platform moving speed of 30 mm / second, and a hair pressing length of 0.3 mm. Thereafter, a haze meter was used to measure the haze value of the liquid crystal alignment film, and the difference (haze change value) from the haze value before the friction treatment was 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-1).

[0313] Haze change (%) = Hz2 - Hz1...(z-1)

[0314] A change in the haze value of the liquid crystal alignment film of less than 0.5% was evaluated as "excellent," a change of 0.5% or more but less than 1.0% was evaluated as "good," and a change of 1.0% or more was evaluated as "poor." A change in the haze value of less than 1.0% indicates high friction resistance (abrasion resistance), meaning the liquid crystal alignment film has good mechanical properties. The results were evaluated as "good" in this example.

[0315] (5) Evaluation of liquid crystal orientation

[0316] The liquid crystal display element manufactured in (3) was observed under a microscope at 50x magnification to determine the presence or absence of abnormal domains in the brightness and darkness changes when a voltage of 5 V was turned on and off (applied and released). The alignment order was evaluated as "good" if no abnormal domains were observed, and "poor" if abnormal domains were observed. The results were evaluated as "good" in this example.

[0317] (6) Evaluation of liquid crystal orientation (AC residual image characteristics)

[0318] For the liquid crystal display element manufactured in (3), a birefringence meter (manufactured by AXOMETRICS, AXOSTEP high-precision Mueller Matrix Imaging Polarimeter) was used to measure the change in the liquid crystal azimuth angle before and after driving for 68 hours under backlight irradiation with an AC voltage of 11V. In the evaluation, the change in the liquid crystal azimuth angle was set to "excellent" when it was less than 0.1 degrees, "good" when it was more than 0.1 degrees and less than 0.3 degrees, and "poor" when it was more than 0.3 degrees. The smaller the change in the liquid crystal azimuth angle, the less likely it is to produce AC afterimages even when the liquid crystal display element is driven for a long time, and it can be said that the liquid crystal orientation is better. As a result, the evaluation was "good" in this embodiment.

[0319] [Example 2 to Example 19, Comparative Examples 1 to 5]

[0320] In Example 1, except that the polymer contained in the liquid crystal aligning agent was changed as shown in Table 3 below, a liquid crystal aligning agent was prepared in the same manner as in Example 1, a liquid crystal alignment film was formed by a photo-alignment method, and an FFS liquid crystal display element was manufactured and various evaluations were performed. The evaluation results are shown in Table 3 below.

[0321] [Example 20: Rubbed Alignment FFS Type Liquid Crystal Display Element]

[0322] (1) Preparation of liquid crystal alignment agent

[0323] The polymer components (solid content conversion: 30 parts by mass of polymer (PI-1) and 70 parts by mass of polymer (PA-12)), 4 parts by mass of compound (AD-2), and 1 part by mass of compound (AD-3) were diluted with NMP, GBL, BC, and DAA to obtain a solution having a solid content concentration of 4.0% and a solvent composition ratio of NMP:GBL:BC:DAA = 30:40:10:20 (mass ratio). The solution was filtered through a filter with a pore size of 0.2 μm to prepare a liquid crystal aligning agent (AL-25).

[0324] (2) Formation of liquid crystal alignment film based on rubbing alignment method

[0325] The liquid crystal alignment agent (AL-25) prepared in (1) was applied to the glass substrate on which a flat electrode, an insulating layer and a comb-shaped electrode were sequentially stacked on one side and the opposite glass substrate on which no electrode was set using a spin coater. After heating on a hot plate at 80°C for 1 minute, the liquid crystal alignment agent (AL-25) was heated in an oven at 230°C in which nitrogen was replaced in the reservoir for 30 minutes to form a coating with an average film thickness of 100 nm. For the surface of the coating, a friction machine having a roller wound with cotton cloth was used to perform a friction orientation treatment twice at a roller speed of 1000 rpm, a platform moving speed of 30 mm / s and a hair pressing length of 0.3 mm. The coating subjected to the friction orientation treatment was ultrasonically cleaned in ultrapure water for 1 minute and then dried in an oven at 100°C for 10 minutes to form a liquid crystal alignment film.

[0326] (3) Manufacturing of FFS type liquid crystal display elements

[0327] An FFS type liquid crystal display element was manufactured in the same manner as in Example 1 (3).

[0328] (4) Evaluation of friction resistance (film strength)

[0329] The mechanical properties (friction resistance) were evaluated in the same manner as in (4) of Example 1. The results were evaluated as "good" in this example.

[0330] (5) Evaluation of liquid crystal orientation

[0331] The liquid crystal orientation was evaluated in the same manner as in (5) of Example 1. As a result, the evaluation was "good" in this Example.

[0332] (6) Evaluation of AC afterimage characteristics

[0333] The AC afterimage characteristic was evaluated in the same manner as in (6) of Example 1. The result was "good" in this example.

[0334] [Examples 21 to 25, Comparative Examples 6 and 7]

[0335] In Example 20, except that the polymer contained in the liquid crystal aligning agent was changed as shown in Table 3 below, a liquid crystal aligning agent was prepared in the same manner as in Example 20, a liquid crystal alignment film was formed by a rubbing alignment method, and an FFS liquid crystal display element was manufactured and various evaluations were performed. The evaluation results are shown in Table 3 below.

[0336] [Table 3]

[0337]

[0338] As shown in Table 3, the liquid crystal alignment agents of Examples 1 to 25 containing polymer (P) were rated "Excellent" or "Good" in terms of mechanical properties, liquid crystal orientation, and AC afterimage properties, demonstrating a good balance of these properties. In contrast, the liquid crystal alignment agents of Comparative Examples 1 to 7, which did not contain polymer (P), were inferior to the examples in terms of at least one of mechanical properties and AC afterimage properties.

[0339] Hereinafter, the results of Examples and Comparative Examples will be examined, but this examination is merely speculation and does not limit the present invention in any way.

[0340] Regarding the mechanical properties, Examples 1 to 25 were evaluated as "excellent" or "good". These liquid crystal aligning agents contain the following polymers, which have the following partial structure in the main chain, namely, a partial structure consisting of three or more consecutive hydrogen bonding groups (-NH-, -N(Boc)-, -C(=O)-, -SO2-) that can become hydrogen bond donors or two consecutive hydrogen bond acceptors. Therefore, it is speculated that multi-point hydrogen bonds can be formed through the partial structure, thereby making the intermolecular interaction in the film strong and the mechanical properties good. Furthermore, the liquid crystal aligning agents containing polymers having an acylhydrazine structure in the main chain (Examples 3 to 19, Examples 21 to 25) show particularly excellent mechanical properties.

[0341] On the other hand, in the cases where an amide structure was introduced in place of the multi-point hydrogen bonding structure, as in Comparative Examples 1, 5, and 7, and in the case where a nitrogen-containing heterocycle was introduced in place of the multi-point hydrogen bonding structure, as in Comparative Example 3, the mechanical properties were evaluated as "poor." It is speculated that when a nitrogen-containing heterocycle is introduced in place of the multi-point hydrogen bonding structure, salts are formed due to acid-base interactions in the polymer, resulting in embrittlement of the film.

[0342] Based on the above content, it is speculated that the polymer (P) has a multi-point hydrogen bond structure with continuous groups that can become hydrogen bond donors or groups that can become hydrogen bond acceptors, so the toughness or wear resistance of the liquid crystal orientation film is improved through intermolecular interactions, and as a result, the film cutting caused by friction treatment is suppressed.

[0343] Regarding the AC afterimage characteristics, Examples 1 to 25 were rated as "excellent" or "good." This is presumably because the polymer (P) contained in the liquid crystal alignment agents of Examples 1 to 25 has high thermal realignment (increased anisotropy) based on heating after exposure in the photoalignment method, and high extensibility on the film surface based on rubbing treatment in the rubbing alignment method. Therefore, the orientation order of the molecular chains of the liquid crystal alignment film is high and the orientation restriction force on the liquid crystal is excellent. Furthermore, the liquid crystal alignment agents having an acylhydrazine structure or an amide structure in the main chain of the polymer (Examples 4, 6 to 13, 15 to 17, 19, 21 to 22, 24 to 25) exhibit particularly excellent AC afterimage characteristics.

[0344] On the other hand, the AC afterimage characteristics of the liquid crystal alignment agents containing polymers having a urea structure in the main chain (Comparative Example 4, Comparative Example 6) are worse than those of Examples 1 to 25. The reason for this is believed to be that the thermal rearrangement or extensibility of the polymers contained in the liquid crystal alignment agents of Comparative Examples 4 and 6 is not sufficient. In addition, it is speculated that in Comparative Example 2, which contains a polymer having an oxamide structure without a thermally detachable group in the main chain instead of polymer (P), the compatibility between the polymers is high, so it is difficult for the photosensitive polymer to exist in the surface layer of the liquid crystal alignment film, and the AC afterimage characteristics are deteriorated. Furthermore, it is speculated that in Comparative Example 3, the polymer contained in the liquid crystal alignment agent has a nitrogen-containing heterocyclic ring, and the thermal rearrangement based on the acid-base interaction in the polymer is reduced, so the AC afterimage characteristics are deteriorated.

[0345] It is speculated that the arrangement of the group (D) that can be a hydrogen bond donor and the group (A) that can be a hydrogen bond acceptor in the multi-point hydrogen bond structure will affect the strength or directionality of the intermolecular interaction. The polymers (P) used in Examples 1 to 14 have an oxamide structure (DAAD type), a diacylhydrazine structure (ADDA type), a sulfonamide structure (DAAD type, -SO2- has two oxo groups (=O), and therefore has two consecutive hydrogen bond acceptors) or an acylhydrazine structure (DDA type). These cases are speculated to be structures consisting of two consecutive groups of either a group (D) that can be a hydrogen bond donor and a group (A) that can be a hydrogen bond acceptor (i.e., DD or AA), and thus, both of the opposite characteristics of mechanical properties and AC afterimage characteristics are excellent, and the balance of various characteristics is good. On the other hand, it is speculated that the urea structure (DAD type) of the polymer contained in the liquid crystal alignment agents of Comparative Examples 4 and 6 has insufficient thermal rearrangement or extensibility, and that the amide structure (DA type) of the polymer contained in the liquid crystal alignment agents of Comparative Examples 1, 5, and 7 has insufficient intermolecular interaction, resulting in a poor balance between mechanical properties and AC afterimage properties.

[0346] Furthermore, it is believed that the thermally detachable group can improve the solubility of the polymer by protecting the highly polar hydrogen-bonding functional groups, and can also make the polymer hydrophobic (lower the surface free energy), thereby controlling the phase separation properties. Therefore, it is speculated that by introducing the thermally detachable group into the polymer exhibiting photosensitivity or stretchability, the photosensitivity or stretchability of the polymer is preferentially present on the surface of the liquid crystal alignment film, thereby contributing to the development of good liquid crystal orientation and AC afterimage characteristics.

[0347] From the above, it turns out that according to the liquid crystal aligning agent containing the polymer (P), the dynamic characteristics of the liquid crystal aligning film are favorable, and a liquid crystal element which is favorable in liquid-crystal orientation and AC afterimage characteristics can be obtained.

Claims

1. A liquid crystal aligning agent comprising a polymer containing a structural unit derived from a diamine represented by the following formula (0); In formula (0), R 1 and R 2 are independently a halogen atom or a monovalent organic group; Ar 1 and Ar 2 are each independently a group formed by removing p+2 hydrogen atoms from a benzene ring, a naphthalene ring or a biphenyl ring; p and q are each independently an integer from 0 to 4; X 1 and X 2 are independently a single bond or a divalent organic group; Y 1 -CO-CO-, -SO2-, -CO-NR 5 -* N or -SO2-NR 5 -* N ; R 5 is a hydrogen atom or a monovalent organic group; "* N "For"-COOZ 1 "The bond to the nitrogen atom to which Z is bonded; 1 It is a monovalent organic group.

2. The liquid crystal aligning agent according to claim 1, wherein X in the formula (0) 1 and X 2 are independently a single bond, a divalent hydrocarbon group having 1 to 12 carbon atoms, an oxygen atom, a sulfur atom, -CO-, -SO2-, -NR 6 -, -C=N-, or any methylene group in a divalent hydrocarbon group having 2 to 12 carbon atoms, connected with an oxygen atom, a sulfur atom, -CO-, -SO2-, -NR 6 - or -C=N-substituted divalent group, wherein R 6 It is a hydrogen atom or a monovalent organic group.

3. The liquid crystal aligning agent according to claim 1, wherein Z in the formula (0) 1 It is a monovalent aliphatic hydrocarbon group having 1 to 6 carbon atoms.

4. The liquid crystal alignment agent according to claim 1, wherein When p in the formula (0) is 1 or greater, R 1 is an alkyl group having 1 to 3 carbon atoms, When q in the formula (0) is 1 or greater, R 2 It is an alkyl group having 1 to 3 carbon atoms. The liquid crystal alignment agent according to claim 1 , wherein: The polymer is at least one selected from the group consisting of polyamic acid, polyamic acid ester, polyimide, polyamide, polyamideimide, polyurea, and polyimide. The liquid crystal aligning agent according to claim 1 , further comprising a polymer containing no structural unit derived from the diamine represented by the formula (0).

7. The liquid crystal alignment agent according to claim 1, wherein The diamine represented by the formula (0) is represented by the following formula (1); In formula (1), R 1 and R 2 are each independently a halogen atom or a monovalent organic group; p and q are each independently an integer of 0 to 4; X 1 and X 2 are independently a single bond or a divalent organic group; Y 1 -CO-CO-, -SO2-, -CO-NR 5 -* N or -SO2-NR 5 -* N ; R 5 is a hydrogen atom or a monovalent organic group; "* N "For"-COOZ 1 "The bond to the nitrogen atom to which Z is bonded; 1 It is a monovalent organic group. 8 . A liquid crystal alignment film formed using the liquid crystal alignment agent according to claim 1 . 9 . A liquid crystal element comprising the liquid crystal alignment film according to claim 8 .

10. A polymer comprising a structural unit derived from a diamine represented by the following formula (0); In formula (0), R 1 and R 2 are independently a halogen atom or a monovalent organic group; Ar 1 and Ar 2 are each independently a group formed by removing p+2 hydrogen atoms from a benzene ring, a naphthalene ring or a biphenyl ring; p and q are each independently an integer from 0 to 4; X 1 and X 2 are independently a single bond or a divalent organic group; Y 1 -CO-CO-, -SO2-, -CO-NR 5 -* N or -SO2-NR 5 -* N ; R 5 is a hydrogen atom or a monovalent organic group; "* N "For"-COOZ 1 "The bond to the nitrogen atom to which Z is bonded; 1 It is a monovalent organic group.

11. A diamine represented by the following formula (0); In formula (0), R 1 and R 2 are independently a halogen atom or a monovalent organic group; Ar 1 and Ar 2 are each independently a group formed by removing p+2 hydrogen atoms from a benzene ring, a naphthalene ring or a biphenyl ring; p and q are each independently an integer from 0 to 4; X 1 and X 2 are independently a single bond or a divalent organic group; Y 1 -CO-CO-, -SO2-, -CO-NR 5 -* N or -SO2-NR 5 -* N ; R 5 is a hydrogen atom or a monovalent organic group; "* N "For"-COOZ 1 "The bond to the nitrogen atom to which Z is bonded; 1 It is a monovalent organic group.

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