Liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal element using the same

Abstract

The present application relates to liquid crystal alignment agent, liquid crystal alignment film and using it's liquid crystal element, its task is to provide a kind of high adhesion of sealing agent's liquid crystal alignment film, further provide the liquid crystal alignment film capable of forming such liquid crystal alignment film for photo-orientation liquid crystal alignment agent;Solution is a kind of liquid crystal alignment agent, it contains the polyamide acid or its derivative obtained by reacting tetracarboxylic acid derivative with diamine type, wherein, liquid crystal alignment agent includes the compound represented by formula (I) and the compound such as formula (AN-2-2) as tetracarboxylic acid derivative, in formula (I), the group of *1 and *1' and the group of *2 and *2' can be bonded with the same oxygen atom;R b1 ~R b4 It is independently hydrogen atom or methyl;In formula (AN-2-2), m is an integer of 1-12.

Description

TECHNICAL FIELD

[0001] The present application relates to a liquid crystal alignment agent, a liquid crystal alignment film, and a liquid crystal element using the same. In detail, it relates to a photo-alignment liquid crystal alignment agent (hereinafter, sometimes referred to as a liquid crystal alignment agent) for forming a liquid crystal alignment film (hereinafter, sometimes referred to as a photo-alignment film or an alignment film) of a photo-alignment type, a liquid crystal alignment film of a photo-alignment type formed using the liquid crystal alignment agent, and a liquid crystal display element having the liquid crystal alignment film. BACKGROUND

[0002] A liquid crystal element in which an optical phenomenon such as refraction, scattering, reflection, or the like of an electromagnetic wave incident into the element is caused by controlling or modulating the alignment state of a liquid crystal layer in the element is known. Specifically, in addition to a liquid crystal display element described below, a liquid crystal antenna, a light control window, an optical compensation material, and a variable phase shifter are known.

[0003] As a liquid crystal display element, various driving modes such as a TN (Twisted Nematic) mode, an STN (Super Twisted Nematic) mode, an IPS (In-Plane Switching) mode, an FFS (Fringe Field Switching) mode, a VA (Multi-domain Vertical Alignment) mode of a vertical alignment type, and the like are known. These liquid crystal display elements are applied to image display devices of various electronic devices such as television sets and mobile phones, and are developed with the aim of further improving display quality. Specifically, improvement in the performance of a liquid crystal display element is achieved not only by improvement in the driving mode and the element structure, but also by the constituent members used in the element. Furthermore, among the constituent members used in a liquid crystal display element, an alignment film is one of the important materials involved in display quality, and research on the alignment film is actively conducted in order to cope with the requirements for high quality of a liquid crystal display element.

[0004] Here, the liquid crystal alignment film is provided in contact with a liquid crystal layer on a pair of substrates provided on both sides of the liquid crystal layer of a liquid crystal display element, and has a function of aligning liquid crystal molecules constituting the liquid crystal layer with a certain regularity with respect to the substrates. By using a liquid crystal alignment film having high liquid crystal alignment properties, a liquid crystal display element having high contrast and improved image sticking characteristics can be achieved (for example, refer to Patent Documents 1 and 2).

[0005] Further, in recent years, in liquid crystal display elements, narrow frame in which the frame is made narrow and the display screen is enlarged is being developed. In this, in order to enlarge the display region for the narrow frame, it is necessary to print a liquid crystal alignment film to the end of the substrate and coat a sealant on the liquid crystal alignment film. From such a situation, a liquid crystal alignment film having high adhesion to the sealant has also been developed (for example, Patent Literatures 7 to 9).

[0006] In the formation of such a liquid crystal alignment film, currently, a solution (varnish) in which polyamic acid, soluble polyimide, or polyamic acid ester is dissolved in an organic solvent is mainly used. In order to form a liquid crystal alignment film by these varnishes, after the varnish is coated on a substrate, the coating film is cured by heating or the like to form a polyimide-based liquid crystal alignment film, and orientation processing suitable for the above-described display mode is performed as necessary. As the orientation processing method, there are known a rubbing method which adjusts the direction of polymer molecules by wiping the surface of the alignment film with a cloth or the like, and a photo-alignment method which imparts anisotropy to the film by causing photochemical changes such as photodecomposition, photoisomerization, dimerization, or the like of polymer molecules by irradiating linearly polarized ultraviolet rays to the alignment film, in which the photo-alignment method has higher uniformity of orientation than the rubbing method, and since it is a non-contact orientation processing method, it has advantages that the film is not damaged, it is possible to reduce causes of display defects of the liquid crystal display element such as dust, static electricity, or the like.

[0007] As a liquid crystal alignment film using such a photo-alignment method, for example, Patent Literatures 1 to 5 describe the following: azodiamino benzene or the like is used as a raw material, and a photoisomerization technique is applied, thereby obtaining a photo-alignment film having large anchoring energy and good liquid crystal alignment properties. Patent Literature 6 describes the content of obtaining a photo-alignment film having high transparency and good liquid crystal alignment properties by applying a photodecomposition type technique.

[0008] Prior Art Documents

[0009] Patent Literature

[0010] Patent Literature 1: Japanese Patent Application Laid-Open No. 2010-197999;

[0011] Patent Literature 2: International Publication No. 2013 / 157463;

[0012] Patent Literature 3: Japanese Patent Application Laid-Open No. 2005-275364;

[0013] Patent Literature 4: Japanese Patent Application Laid-Open No. 2007-248637;

[0014] Patent Literature 5: International Publication No. 2015 / 016118;

[0015] Patent Literature 6: Japanese Patent Application Laid-Open (JP A) No. 2012-155311

[0016] Patent Literature 7: Japanese Patent Application Laid-Open (JP A) No. 2017-198975

[0017] Patent Literature 8: International Publication No. 2016 / 043230

[0018] Patent Literature 9: Japanese Patent Application Laid-Open (JP A) No. 2018-106096 SUMMARY

[0019] PROBLEMS TO BE SOLVED BY THE INVENTION

[0020] In recent years, with the spread of flat panel liquid crystal display elements and smartphones, development of liquid crystal display elements with narrow frames and large display screens is being conducted. In this regard, in order to expand the display area for narrow frame, it is necessary to print a liquid crystal alignment film up to the end of the substrate and coat a sealant on the liquid crystal alignment film.

[0021] From such a situation, a liquid crystal alignment film with high adhesion to a sealant is required, and as a research and development thereof, a study to improve the adhesion of the sealant to the liquid crystal alignment film by using a compound having a polar group for a raw material monomer of polyamic acid and a polymer thereof has been conducted. For example, in Patent Literatures 7 to 9, a liquid crystal display element in which the adhesion of a liquid crystal alignment film to a sealant is improved by using a specific tetracarboxylic dianhydride or a diamine is proposed.

[0022] However, the expectation for narrow frame is further improved, and a liquid crystal alignment film with better adhesion to a sealant is required.

[0023] The present application has an object to provide a liquid crystal alignment film with high adhesion to a sealant, and further to provide a photo-alignment liquid crystal alignment agent capable of forming such a liquid crystal alignment film.

[0024] MEANS FOR SOLVING PROBLEMS

[0025] The present inventors found that the above problems can be solved by a liquid crystal alignment agent containing a polyamic acid or a derivative thereof composed of a raw material composition containing a compound represented by Formula (I), and at least one compound selected from the group consisting of Formula (AN-2-1), Formula (AN-2-2), Formula (AN-2-4), and Formulae (AN-2-6) to (AN-2-8), thereby completing the present application.

[0026] The present application includes the following structures.

[0027] [1] A liquid crystal alignment agent containing a polyamic acid or a derivative thereof obtained by reacting a tetracarboxylic acid derivative with a diamine, wherein the liquid crystal alignment agent comprises a compound represented by formula (I), and at least one selected from the group consisting of formula (AN-2-1), formula (AN-2-2), formula (AN-2-4), and formula (AN-2-6) to formula (AN-2-8) as the tetracarboxylic acid derivative.

[0028]

[0029] In formula (I), *1, *1', *2, and *2' are a binding bond, each independently bonded to a hydroxyl group, a chlorine atom, or an alkoxy group having 1 to 6 carbon atoms, and at least one of the groups of *1 and *1' and the groups of *2 and *2' can be bonded to the same oxygen atom;

[0030] R b1 , R b2 , R b3 , and R b4 each independently are a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group;

[0031]

[0032] In formula (AN-2-2), m is an integer of 1 to 12.

[0033] [2] The liquid crystal alignment agent according to [1], wherein the at least one selected from the group consisting of the formula (AN-2-1), formula (AN-2-2), formula (AN-2-4), and formula (AN-2-6) to formula (AN-2-8) is at least one selected from the group consisting of formula (AN-2-1), formula (AN-2-2), and formula (AN-2-4).

[0034]

[0035] In formula (AN-2-2), m is an integer of 1 to 12.

[0036] [3] The liquid crystal alignment agent according to [1], wherein the at least one selected from the group consisting of the formula (AN-2-1), formula (AN-2-2), formula (AN-2-4), and formula (AN-2-6) to formula (AN-2-8) is formula (AN-2-2).

[0037]

[0038] In formula (AN-2-2), m is an integer of 1 to 12.

[0039] [4] The liquid crystal aligning agent according to any one of [1] to [3], wherein the diamine-based compound contains at least one selected from the group consisting of formula (DI-4-1), formula (DI-5-1), formula (DI-13), and formula (DI-17).

[0040]

[0041] In formula (DI-5-1), m is an integer of 1 to 12;

[0042] In formula (DI-13), R 23 independently an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or -Cl, p and q are each independently an integer of 0 to 4;

[0043] In formula (DI-17), R 23 independently an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or -Cl, p is independently an integer of 0 to 4, R 25 independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or tert-butoxycarbonyl, Z is a divalent group containing an alkylene group having 1 to 10 carbon atoms, and at least one CH2in the alkylene group having 1 to 10 carbon atoms can be replaced with NH, but NH is not adjacent.

[0044] [5] The liquid crystal aligning agent according to any one of [1] to [4], wherein the liquid crystal aligning agent contains a polyamic acid or a derivative thereof obtained by reacting a tetracarboxylic acid derivative other than the compound represented by formula (AN-2-1), formula (AN-2-2), formula (AN-2-4), or formula (AN-2-6) to formula (AN-2-8) with a diamine-based compound.

[0045] [6] A liquid crystal aligning film formed from the liquid crystal aligning agent according to any one of [1] to [5].

[0046] [7] A liquid crystal element having the liquid crystal aligning film according to [6].

[0047] [8] A method for producing a liquid crystal aligning film, comprising: a step of applying the liquid crystal aligning agent according to any one of [1] to [5] to a substrate; a step of firing the substrate; and a step of irradiating the substrate with polarized ultraviolet light.

[0048] Effects of the Invention

[0049] By using the liquid crystal aligning agent for photo-alignment of the present application, a liquid crystal aligning film having high adhesion to a sealing agent can be obtained. Furthermore, by using the liquid crystal aligning film, a liquid crystal display element having excellent display quality can be realized. DETAILED DESCRIPTION

[0050] The present application is described in detail below. The description of the components described below is sometimes based on representative embodiments and specific examples, but the present application is not limited to such embodiments. The "liquid crystal alignment agent" in the present application is a liquid crystal alignment agent that can impart anisotropy by irradiation of polarized ultraviolet light when forming the film on a substrate, and is sometimes simply referred to as "liquid crystal alignment agent" in the present specification, and is sometimes referred to as "liquid crystal alignment agent for photo-alignment". Furthermore, in the present application, "tetracarboxylic acid derivative" refers to tetracarboxylic dianhydride, tetracarboxylic diester, or tetracarboxylic diester dihalide. Sometimes, tetracarboxylic diester and tetracarboxylic diester dihalide are collectively referred to as derivatives of tetracarboxylic dianhydride. Furthermore, in the present application, diamines and dihydrazides are sometimes referred to as "diamine-based compounds". In the chemical formulae of the present specification, * represents a binding bond.

[0051] <The liquid crystal alignment agent for photo-alignment of the present application>

[0052] The liquid crystal alignment agent for photo-alignment of the present application is characterized by containing at least one polymer selected from the group consisting of polyamic acid and polyamic acid derivative, which is obtained by reacting a tetracarboxylic acid derivative with a diamine-based compound, as a raw material of the polymer, and contains a compound represented by formula (I), and at least one selected from the group consisting of formula (AN-2-1), formula (AN-2-2), formula (AN-2-4), and formula (AN-2-6) to formula (AN-2-8). Sometimes, the polymer is referred to as the polymer of the present application. In the present application, polyamic acid derivative refers to polyimide, partial polyimide, polyamic acid ester, polyamic acid-polyamide copolymer, and polyamide-imide.

[0053] <The type of the polymer>

[0054] The polyamic acid and the polyamic acid derivative are described in detail below.

[0055] Here, the polyamic acid is a polymer synthesized by the polymerization reaction of the tetracarboxylic dianhydride represented by formula (AN) and the diamine-based compound represented by formula (DI), and has a structural unit represented by formula (PAA). When the liquid crystal alignment agent containing the polyamic acid is subjected to heat baking in the process of forming a liquid crystal alignment film, the polyamic acid is imidized, and a polyimide liquid crystal alignment film having a structural unit represented by formula (PI) can be formed.

[0056]

[0057] In formula (AN), formula (PAA), and formula (PI), X 1 is a tetravalent organic group. In formula (DI), formula (PAA), and formula (PI), X 2 is a divalent organic group. Regarding X 1The preferable range and specific examples of the 4-valent organic group in the formula (PAA) can be referred to the corresponding structure of the tetracarboxylic dianhydride described in the present specification. As for X 2 The preferable range and specific examples of the 2-valent organic group in the formula (PAA) can be referred to the corresponding structure of the diamine or Dihydrazide described in the column of diamine in the present specification.

[0058] The polyamic acid derivative is a compound in which a part of the polyamic acid is substituted with other atom or atomic group to change the property, and a compound in which the solubility to the solvent used in the liquid crystal aligning agent is particularly preferably improved. As such polyamic acid derivative, specifically, there can be mentioned: 1) polyimide obtained by subjecting all of the amino group and carboxyl group of the polyamic acid to dehydration ring closure reaction; 2) partial polyimide obtained by subjecting a part of the polyamic acid to dehydration ring closure reaction; 3) polyamic acid ester in which the carboxyl group of the polyamic acid is converted to ester; 4) polyamic acid-polyamide copolymer obtained by substituting a part of the acid dianhydride contained in the tetracarboxylic dianhydride compound with organic dicarboxylic acid and subjecting to reaction; and 5) polyamide-imide obtained by subjecting a part or all of the polyamic acid-polyamide copolymer to dehydration ring closure reaction. Among these derivatives, as polyimide, there can be mentioned polyimide having a structural unit represented by the above formula (PI), and as polyamic acid ester, there can be mentioned polyamic acid ester having a structural unit represented by the following formula (PAE).

[0059]

[0060] In the formula (PAE), X 1 is a 4-valent organic group, X 2 is a 2-valent organic group, and Y is independently an alkyl group. As for X 1 , X 2 , the preferable range and specific examples can be referred to the description of X 1 , X 2 in the formula (PAA). In Y, a straight chain or branched chain alkyl group having 1 to 6 carbon atoms is preferable, and methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group or tert-butyl group is more preferable.

[0061] The tetracarboxylic dianhydride and diamine used in the synthesis of the polyamic acid can be one kind each, or two or more kinds each.

[0062] In the case where the above polyamic acid of the present application is used as a polyimide as a polyamic acid derivative, a polyimide can be obtained by subjecting the obtained polyamic acid solution to an imidization reaction with an acid anhydride such as acetic anhydride, propionic anhydride, trifluoroacetic anhydride or the like as a dehydrating agent, and a tertiary amine such as triethylamine, pyridine, collidine or the like as a dehydrating ring closure catalyst at a temperature of 20 to 150°C. Alternatively, a polyimide can also be obtained by precipitating the polyamic acid from the obtained polyamic acid solution using a large amount of a poor solvent (alcohol solvents such as methanol, ethanol, isopropanol, glycol solvents), subjecting the precipitated polyamic acid to an imidization reaction with the above dehydrating agent and dehydrating ring closure catalyst in a solvent such as toluene, xylene or the like at a temperature of 20 to 150°C.

[0063] In the above imidization reaction, the ratio of the dehydrating agent to the dehydrating ring closure catalyst is preferably 0.1 to 10 (molar ratio). The total amount of the dehydrating agent and the dehydrating ring closure catalyst used is preferably 1.5 to 10 times the molar amount of the total of the tetracarboxylic dianhydride used in the synthesis of the polyamic acid. By adjusting the amount of the dehydrating agent, the amount of the catalyst, the reaction temperature and the reaction time used in the imidization reaction, the degree of imidization can be controlled, whereby a partial polyimide in which only a part of the polyamic acid has been imidized can be obtained. The obtained polyimide can be separated from the solvent used in the reaction, redissolved in another solvent and used as a liquid crystal alignment agent, or can also be used as a liquid crystal alignment agent without being separated from the solvent.

[0064] The polyamic acid ester can be obtained by a method in which a polyamic acid is synthesized by reacting a tetracarboxylic dianhydride or a tetracarboxylic diester dichloride derived from a tetracarboxylic dianhydride with a diamine. The tetracarboxylic diester derived from a tetracarboxylic dianhydride can be obtained, for example, by ring opening by reacting a tetracarboxylic dianhydride with 2 equivalents of an alcohol, and the tetracarboxylic diester dichloride can be obtained by reacting a tetracarboxylic diester with 2 equivalents of a chlorinating agent such as thionyl chloride or the like. Furthermore, the polyamic acid ester can have only an amic acid ester structure, or can be a partial ester in which an amic acid structure and an amic acid ester structure coexist.

[0065] The polyamic acid or the derivative thereof of the present application can be manufactured in the same manner as the known polyamic acid or the derivative thereof used in the formation of a film of a polyimide. The total amount of the tetracarboxylic derivative is preferably 0.9 to 1.1 moles per 1 mole of the total of the diamines.

[0066] The liquid crystal alignment agent of the present application can contain only one of these polyamic acid, polyamic acid ester and polyimide obtained by imidizing them, or can contain two or more.

[0067] The molecular weight of the polyamide acid or the derivative thereof of the present application is preferably 5000 to 500000, more preferably 5000 to 50000, in terms of the weight average molecular weight (Mw) in terms of polystyrene. The molecular weight of the polyamide acid or the derivative thereof can be found by measurement using a gel permeation chromatography (GPC) method.

[0068] The polyamide acid or the derivative thereof of the present application can be confirmed to exist by analyzing the solid component obtained by precipitation using a large amount of a poor solvent using IR (Infrared Spectrometry), NMR (Nuclear Magnetic Resonance). In addition, a decomposed product of the polyamide acid or the derivative thereof is obtained by an aqueous solution of a strong base such as KOH, NaOH, an extract of the decomposed product is obtained by an organic solvent, and the extract is analyzed using GC (Gas Chromatography), HPLC (High Performance Liquid Chromatography), or GC-MS (Gas Chromatography-Mass Spectrometry), whereby the used monomer can be confirmed.

[0069] < Tetracarboxylic acid derivative >

[0070] In the polymer of the present application, as a raw material, a compound represented by Formula (I), and at least one compound selected from the group consisting of Formula (AN-2-1), Formula (AN-2-2), Formula (AN-2-4), and Formula (AN-2-6) to Formula (AN-2-8) can be contained, and a tetracarboxylic acid derivative other than these can also be contained. Specific examples of each compound are described below.

[0071] < Compound represented by Formula (I) >

[0072] The compound represented by Formula (I) used in the raw material of the polymer of the present application is described.

[0073]

[0074] In Formula (I), *1, *1', *2, and *2' are binding bonds, each independently bonded to a hydroxyl group, a chlorine atom, or an alkoxy group having a carbon atom number of 1 to 6, and at least one of the group of *1 and *1', and the group of *2 and *2' can be bonded to the same oxygen atom;

[0075] R b1 , R b2 , R b3and R b4 each independently is a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group.

[0076] As a specific example of the alkoxy group having 1 to 6 carbon atoms, a methoxy group, an ethoxy group, a propoxy group, an isopropoxy group, a butoxy group, an isobutoxy group, or a tert-butoxy group can be given. From the viewpoint of easiness of imidization, a methoxy group is preferred.

[0077] In the formula (I), there are included: a mode in which all of the four binding sites are bonded to any one of a hydroxyl group, a chlorine atom, and an alkoxy group having 1 to 6 carbon atoms; a mode in which either of the group of *1 and *1' and the group of *2 and *2' is bonded to the same oxygen atom, and the remaining two binding sites are bonded to any one of a hydroxyl group, a chlorine atom, and an alkoxy group having 1 to 6 carbon atoms; and a mode in which both of the group of *1 and *1' and the group of *2 and *2' are respectively bonded to the same oxygen atom. Of these, preferred are: a mode in which all of the four binding sites are bonded to any one of a hydroxyl group, a chlorine atom, and an alkoxy group having 1 to 6 carbon atoms; and a mode in which both of the group of *1 and *1' and the group of *2 and *2' are respectively bonded to the same oxygen atom.

[0078] As the halogen atom in the above R b1 , R b2 , R b3 , and R b4 , a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and the like can be given. As a specific example of the alkyl group having 1 to 6 carbon atoms, a methyl group, an ethyl group, a propyl group, an isopropyl group, a n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a n-pentyl group, and the like can be given. As a specific example of the alkenyl group having 2 to 6 carbon atoms, for example, a vinyl group, a propenyl group, a butenyl group, and the like can be given, which can be linear or branched. As a specific example of the alkynyl group having 2 to 6 carbon atoms, for example, an ethynyl group, a 1-propynyl group, a 2-propynyl group, and the like can be given. As the monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, a fluoromethyl group, a trifluoromethyl group, a trifluoromethoxy group, and the like can be given.

[0079] From the viewpoint of obtaining a liquid crystal alignment film having high sensitivity, it is preferred that R b1 and R b4 be a methyl group, and R b2 and R b3 be a hydrogen atom.

[0080] The following can be given as preferred examples of the compound represented by the formula (I).

[0081]

[0082] In formulae (I-6) to (I-13), R 11 independently alkyl groups having 1 to 6 carbon atoms. R 11 is preferably a methyl group.

[0083] Among them, in order to obtain a liquid crystal alignment film having high sensitivity, it is preferable to use formula (I-2), formula (I-7), formula (I-9), formula (I-11), or formula (I-13).

[0084] In the polymer of the present application, the compound represented by formula (I) is preferably used in an amount of 50 mol% or more of the total amount of the tetracarboxylic acid derivative used. A plurality of compounds represented by formula (I) can also be used in combination.

[0085] <Tetracarboxylic acid derivative other than formula (I)>

[0086] Hereinafter, as the tetracarboxylic acid derivative other than formula (I), tetracarboxylic dianhydrides represented by formulae (AN-1) to (AN-9), formula (AN-10-1), formula (AN-10-2), formula (AN-11), formula (AN-12), formula (AN-15), and formulae (AN-16-1) to (AN-16-18) will be described. These tetracarboxylic dianhydrides can also be derived to tetracarboxylic diesters, tetracarboxylic diester dichlorides, and used as raw materials for polymers.

[0087] [Tetracarboxylic dianhydride represented by formula (AN-1)]

[0088]

[0089] In formula (AN-1), G 11 is a single bond, an alkylene group having 1 to 12 carbon atoms, 1,4-phenylene, 1,4-cyclohexylene, or formula (G11-1). R 11 independently a hydrogen atom or a methyl group.

[0090]

[0091] In formula (G11-1), X is independently a single bond, -O-, -S-, or -NR 1 , R 1 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, n is independently an integer of 1 to 5, m is an integer of 1 to 3, and the group whose bonding position is not fixed on any one of the carbon atoms constituting the ring indicates that it can bond to any one of the bondable carbon atoms in the ring.

[0092] Examples of the tetracarboxylic dianhydride represented by formula (AN-1) can be given below.

[0093]

[0094]

[0095] In formulae (AN-1-2) and (AN-1-5), each of m is independently an integer of 1 to 12.

[0096] [Four carboxylic acid dianhydride represented by formula (AN-2)]

[0097]

[0098] In formula (AN-2), G 11 is a single bond, an alkylene group having 1 to 12 carbon atoms, a 1,4-phenylene group, or a 1,4-cyclohexylene group. X 11 is a single bond or -CH2-. G 12 is independently any one of the following trivalent groups

[0099] G 12 when G 11 is not a single bond and -CH2-, X 11 is not a single bond.

[0100] Examples of the four carboxylic acid dianhydride represented by formula (AN-2) can be mentioned below.

[0101]

[0102] In formula (AN-2-2), m is an integer of 1 to 12.

[0103] [Four carboxylic acid dianhydride represented by formula (AN-3)]

[0104]

[0105] In formula (AN-3), ring A 11 is a cyclohexane ring or a benzene ring.

[0106] As examples of the four carboxylic acid dianhydride represented by formula (AN-3), the compounds represented by formulae (AN-3-1) and (AN-3-2) below can be mentioned.

[0107]

[0108] [Four carboxylic acid dianhydride represented by formula (AN-4)]

[0109]

[0110] In formula (AN-4), G 13 is a single bond, -(CH2) m -, -O-, -S-, -C(CH3)2, -SO2-, -CO-, -C(CF3)2-, or a divalent group represented by formula (G13-1) below, and m is an integer of 1 to 12. ring A11 Each can be independently a cyclohexane ring or a benzene ring. G 13 Can be combined with ring A 11 Bonded at any position.

[0111]

[0112] In equation (G13-1), G 13a and G 13b Each group is a divalent group, represented independently by a single bond, -O-, -CONH-, or -NHCO-. The phenylene group is preferably 1,4-phenylene or 1,3-phenylene.

[0113] Examples of tetracarboxylic acid dianhydrides represented by formula (AN-4) include compounds represented by formulas (AN-4-1) to (AN-4-31).

[0114]

[0115]

[0116] In equation (AN-4-17), m is an integer from 1 to 12.

[0117]

[0118]

[0119] In equation (AN-5), R 11 It can be a hydrogen atom or a methyl group independently. Two Rs 11 R on the benzene ring 11 It bonds to any of the substituted positions on the benzene ring.

[0120] Examples of tetracarboxylic acid dianhydrides represented by formula (AN-5) include compounds represented by formulas (AN-5-1) to (AN-5-3).

[0121]

[0122] [Tetracarboxylic dianhydride represented by formula (AN-6)]

[0123]

[0124] In equation (AN-6), X 11 Independently a single bond or -CH2-. X 12 It can be -CH2-, -CH2CH2-, or -CH=CH-. n is 1 or 2. When n is 2, there are 2 X's. 12 They can be the same or different.

[0125] As examples of the tetracarboxylic dianhydride represented by formula (AN-6), there can be mentioned compounds represented by the following formulas (AN-6-1) to (AN-6-12).

[0126]

[0127] [Formula (AN-7) represents a tetracarboxylic dianhydride]

[0128]

[0129] In formula (AN-7), X 11 is a single bond or -CH2-.

[0130] As examples of the tetracarboxylic dianhydride represented by formula (AN-7), there can be mentioned compounds represented by the following formulas (AN-7-1) and (AN-7-2).

[0131]

[0132] [Formula (AN-8) represents a tetracarboxylic dianhydride]

[0133]

[0134] In formula (AN-8), X 11 is a single bond or -CH2-. R 12 is a hydrogen atom, a methyl group, an ethyl group or a phenyl group. Ring A 12 is a cyclohexane ring or a cyclohexene ring.

[0135] As examples of the tetracarboxylic dianhydride represented by formula (AN-8), there can be mentioned compounds represented by the following formulas (AN-8-1) and (AN-8-2).

[0136]

[0137] [Formula (AN-9) represents a tetracarboxylic dianhydride]

[0138]

[0139] In formula (AN-9), each of r is independently 0 or 1.

[0140] As examples of the tetracarboxylic dianhydride represented by formula (AN-9), there can be mentioned compounds represented by the following formulas (AN-9-1) to (AN-9-3).

[0141]

[0142] [Formula (AN-10-1) and formula (AN-10-2) represent a tetracarboxylic dianhydride]

[0143]

[0144] [The tetracarboxylic dianhydride represented by formula (AN-11)]

[0145]

[0146] In formula (AN-11), ring A 11 is each independently a cyclohexane ring or a benzene ring.

[0147] As examples of the tetracarboxylic dianhydride represented by formula (AN-11), there are mentioned compounds represented by the following formulae (AN-11-1) to (AN-11-3).

[0148]

[0149] [The tetracarboxylic dianhydride represented by formula (AN-12)]

[0150]

[0151] In formula (AN-12), ring A 11 is each independently a cyclohexane ring or a benzene ring.

[0152] As examples of the tetracarboxylic dianhydride represented by formula (AN-12), there are mentioned compounds represented by the following formulae (AN-12-1) to (AN-12-3).

[0153]

[0154] [The tetracarboxylic dianhydride represented by formula (AN-15)]

[0155]

[0156] In formula (AN-15), w is an integer of 1 to 10.

[0157] As examples of the tetracarboxylic dianhydride represented by formula (AN-15), there are mentioned compounds represented by the following formulae (AN-15-1) to (AN-15-3).

[0158]

[0159] [The tetracarboxylic dianhydride represented by formula (AN-16-1) to (AN-16-18)]

[0160] As examples of the tetracarboxylic dianhydride other than the above, there are mentioned compounds represented by the following formulae (AN-16-1) to (AN-16-18).

[0161]

[0162]

[0163] By using the compound represented by formula (AN-2-1), formula (AN-2-2), formula (AN-2-4), or formula (AN-2-6) to formula (AN-2-8), the sealing adhesion can be improved. Among them, the compound represented by formula (AN-2-1), formula (AN-2-2), or formula (AN-2-4) is more preferable, and formula (AN-2-2) is further preferable, and the compound in which m is 4 or 6 in formula (AN-2-2) is particularly preferable.

[0164] In the polymer of the present application, the use amount of the compound represented by formula (AN-2-1), formula (AN-2-2), formula (AN-2-4), or formula (AN-2-6) to formula (AN-2-8) is preferably 1 to 50 mol%, and more preferably 1 to 30 mol% in the total amount of the tetracarboxylic acid derivative used. A plurality of the compounds represented by formula (AN-2-1), formula (AN-2-2), formula (AN-2-4), or formula (AN-2-6) to formula (AN-2-8) can also be used in combination.

[0165] <DIAMINE CLASSES>

[0166] A known diamine class can be used in the raw material of the polymer of the present application. As specific examples, diamine classes represented by formula (DI-1) to formula (DI-17), formula (DIH-1) to formula (DIH-3) are described.

[0167]

[0168] In formula (DI-1), G 20 is an alkylene group having 1 to 12 carbon atoms or a group represented by formula (DI-1-a). G 20 When G is an alkylene group having 1 to 12 carbon atoms, at least one -CH2- can be substituted with -NH- or -O-, but they are not adjacent, and at least one hydrogen atom of -CH2- can be substituted with a hydroxyl group or a methyl group.

[0169]

[0170] In formula (DI-1-a), each of v is independently an integer of 1 to 6.

[0171] In formula (DI-3), formula (DI-6), and formula (DI-7), G 21 is independently a single bond, -NH-, -NCH3-, -O-, -S-, -S-S-, -SO2-, -CO-, -COO-, -CONCH3-, -CONH-, -C(CH3)2-, -C(CF3)2-, -(CH2) m , -O-(CH2) m-O-, -N(CH3)-(CH2) k -N(CH3)-, -(O-C2H4) m -O-, -O-CH2-C(CF3)2-CH2-O-, -O-CO-(CH2) m -CO-O-, -CO-O-(CH2) m -O-CO-, -(CH2) m -NH-(CH2) m -, k -NH-(CH2) k -, m k -NH-, -CO-C3H6-(NH-C3H6) n -CO- or -S-(CH2) m -S-, m is independently an integer of 1 to 12, k is an integer of 1 to 5, and n is 1 or 2.

[0172] In formula (DI-4), s is independently an integer of 0 to 2.

[0173] In formula (DI-5), G 33 is a single bond, -NH-, -NCH3-, -O-, -S-, -S-S-, -SO2-, -CO-, -COO-, -CONCH3-, -CONH-, -C(CH3)2-, -C(CF3)2-, -(CH2) m -, m -O-, -(O-C2H4) m -O-, -O-CH2-C(CF3)2-CH2-O-, -O-CO-(CH2) m -CO-O-, -CO-O-(CH2) m -O-CO-, -(CH2) m -NH-(CH2) m -, k -NH-(CH2) k -, n -CO- or -S-(CH2) m -S-, -N(Boc)-(CH2) e -, m -N(Boc)-CONH-(CH2) m -, m -N(Boc)-(CH2) m ​or a group represented by the following formula (DI-5-a) or the following formula (DI-5-b), m is independently an integer of 1 to 12, k is an integer of 1 to 5, e is an integer of 2 to 10, and n is 1 or 2. Boc is a tert-butyloxy carbonyl group.

[0174]

[0175] In formula (DI-5-a), each of q is independently an integer of 0 to 6. R 44 is a hydrogen atom, a hydroxyl group, an alkyl group having 1 to 6 carbon atoms, or an alkoxy group having 1 to 6 carbon atoms.

[0176] In formula (DI-6) and formula (DI-7), G 22 is independently a single bond, -0-, -S-, -CO-, -C(CH3)2-, -C(CF3)2-, or an alkylene group having 1 to 10 carbon atoms.

[0177] At least one hydrogen atom in the cyclohexane ring and the benzene ring in formula (DI-2) to formula (DI-7) can be substituted with a fluorine atom, a chlorine atom, an alkyl group having 1 to 3 carbon atoms, a methoxy group, a hydroxyl group, a trifluoromethyl group, a carboxyl group, a carbamoyl group, a phenylamino group, a phenyl group, or a benzyl group, and in formula (DI-4), at least one hydrogen atom in the cyclohexane ring and the benzene ring can be substituted with one selected from the group represented by any one of the following formula (DI-4-a) to formula (DI-4-i), in formula (DI-5), G 33 At least one hydrogen atom in the benzene ring can be substituted with NHBoc or N(Boc)2 when G

[0178]

[0179]

[0180] In formula (DI-4-a) and formula (DI-4-b), R 20 is independently a hydrogen atom or a methyl group. In formula (DI-4-f) and formula (DI-4-g), each of m is independently an integer of 0 to 12, and Boc is a tert-butyloxy carbonyl group.

[0181] The group in formula (DI-2) to formula (DI-7) whose bonding position is not fixed on the carbon atom constituting the ring indicates that its bonding position in the ring is arbitrary.

[0182]

[0183] In formula (DI-11), r is 0 or 1. In formula (DI-8) to formula (DI-11), the bonding position of the amino group bonded to the ring is an arbitrary position.

[0184]

[0185] In formula (DI-12), R 21 and R 22 Each is independently an alkyl or phenyl group having 1 to 3 carbon atoms, G 23 Independently, it is an alkylene, phenylene, or alkyl-substituted phenylene with 1 to 6 carbon atoms, where w is an integer from 1 to 10.

[0186] In formula (DI-13), R 23 Independently, it is an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or -Cl, where p and q are each an independent integer from 0 to 4.

[0187] In formula (DI-14), ring B is a monocyclic heterocyclic aromatic group, and R 24 It can be a hydrogen atom, fluorine atom, chlorine atom, or an alkyl, alkoxy, alkenyl, or alkynyl group having 1 to 6 carbon atoms, where q is an independent integer from 0 to 4. When q is 2 or more, multiple R groups... 24 They can be the same or different. In formula (DI-15), ring C is a heterocyclic aromatic group or a heterocyclic aliphatic group. In formula (DI-16), G... 24 It is a single bond, an alkylene group or a 1,4-phenylene group with 2 to 6 carbon atoms, and r is 0 or 1.

[0188] In formula (DI-17), R 23 Independently, it is an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or -Cl; p is an integer from 0 to 4, R 25 It is independently a hydrogen atom, an alkyl or tert-butoxycarbonyl group having 1 to 4 carbon atoms, and Z is a divalent group having an alkylene group having 1 to 10 carbon atoms. At least one CH2 in the alkylene group having 1 to 10 carbon atoms can be substituted with NH, but NH is not adjacent.

[0189] R 25 A preferred example of an alkyl group having 1 to 4 carbon atoms is methyl. A preferred example of a divalent alkylene group having 1 to 10 carbon atoms in Z is -(CH2). m -Ph-(CH2) m -Ph-, where m is an integer from 1 to 10. Preferably, -(CH2) is used. m -, more preferably -(CH2)2-(ethylene). Here, Ph is 1,4-phenylene.

[0190] In formulas (DI-13) to (DI-17), groups whose bonding positions are not fixed on the carbon atoms constituting the ring indicate that their bonding positions in the ring are arbitrary. The bonding positions of the amino groups at both ends of the ring can be arbitrary, preferably para and meta, and more preferably para.

[0191]

[0192] In formula (DIH-1), G 25 is a single bond, an alkylene group having 1 to 20 carbon atoms, -CO-, -0-, -S-, -S02, -C(CH3)2-, or -C(CF3)2-.

[0193] In formula (DIH-2), ring D is a cyclohexylene group, a phenylene group, or a naphthylene group, and at least one hydrogen atom of the group can be substituted with a methyl group, an ethyl group, or a phenyl group.

[0194] In formula (DIH-3), each of the rings E is independently a cyclohexylene group or a phenylene group, and at least one hydrogen atom of the group can be substituted with a methyl group, an ethyl group, or a phenyl group. The two rings E can be the same as or different from each other. Y is a single bond, an alkylene group having 1 to 20 carbon atoms, -CO-, -0-, -S-, -S02-, -C(CH3)2-, or -C(CF3)2-. In formula (DIH-2) and formula (DIH-3), the bonding position of the -hydrazide group to the ring is an arbitrary position.

[0195] Examples of the diamine represented by formula (DI-1) are shown in the following formulae (DI-1-1) to (DI-1-9).

[0196]

[0197] In formulae (DI-1-7) and (DI-1-8), each of k is independently an integer of 1 to 3. In formula (DI-1-9), each of v is independently an integer of 1 to 6.

[0198] Examples of the diamine represented by formulae (DI-2) to (DI-3) are shown in the following formulae (DI-2-1), (DI-2-2), (DI-3-1) to (DI-3-3).

[0199]

[0200] Examples of the diamine represented by formula (DI-4) are shown in the following formulae (DI-4-1) to (DI-4-27).

[0201]

[0202]

[0203] In formulae (DI-4-20) and (DI-4-21), each of m is independently an integer of 1 to 12.

[0204]

[0205] Examples of the diamine represented by the following formula (DI-5) are shown below.

[0206]

[0207] In formula (DI-5-1), m is an integer of 1 to 12.

[0208]

[0209] In formula (DI-5-12) and formula (DI-5-13), m is each independently an integer of 1 to 12.

[0210]

[0211] In formula (DI-5-16), v is an integer of 1 to 6.

[0212]

[0213]

[0214] In formula (DI-5-35) to formula (DI-5-37), m is each independently an integer of 1 to 12, in formula (DI-5-38), k is each independently an integer of 1 to 5, and in formula (DI-5-40), n is an integer of 1 or 2.

[0215]

[0216] In formula (DI-5-44), e is each independently an integer of 2 to 10, and in formula (DI-5-45), R 43 is a hydrogen atom, a (t-butoxycarbonyl)amino group, or a bis(t-butoxycarbonyl)amino group.

[0217]

[0218]

[0219] Examples of the diamine represented by formula (DI-6) are shown below as formula (DI-6-1) to formula (DI-6-7).

[0220]

[0221] Examples of the diamine represented by formula (DI-7) are shown below as formula (DI-7-1) to formula (DI-7-11).

[0222]

[0223] In formula (DI-7-3) and formula (DI-7-4), m is each independently an integer of 1 to 12, and n is independently 1 or 2.

[0224]

[0225] Examples of the diamine represented by formula (DI-8) are shown by the following formulas (DI-8-1) to (DI-8-4).

[0226]

[0227] Examples of the diamine represented by formula (DI-9) are shown by the following formulas (DI-9-1) to (DI-9-3).

[0228]

[0229] Examples of the diamine represented by formula (DI-10) are shown by the following formulas (DI-10-1) and (DI-10-2).

[0230]

[0231] Examples of the diamine represented by formula (DI-11) are shown by the following formulas (DI-11-1) to (DI-11-3).

[0232]

[0233] Examples of the diamine represented by formula (DI-12) are shown by the following formula (DI-12-1).

[0234]

[0235] Examples of the diamine represented by formula (DI-13) are shown by the following formulas (DI-13-1) to (DI-13-13).

[0236]

[0237]

[0238] Examples of the diamine represented by formula (DI-14) are shown by the following formulas (DI-14-1) to (DI-14-9).

[0239]

[0240] Examples of the diamine represented by formula (DI-15) are shown by the following formulas (DI-15-1) to (DI-15-12).

[0241]

[0242] Examples of the diamine represented by formula (DI-16) are shown by the following formula (DI-16-1).

[0243]

[0244] Examples of the diamine represented by the following formula (DI-17) are shown below.

[0245]

[0246] In formula (DI-17-1), k is an integer of 1 to 6. In formulae (DI-17-2) to (DI-17-3), each of e is independently an integer of 1 to 5, and Boc is a tert-butyloxycarbonyl group. In formula (DI-17-4), each of m is independently 1 or 2, and k is 1 or 2.

[0247] Examples of the compound represented by any one of formulae (DIH-1) to (DIH-3) are shown by the following formulae (DIH-1-1), (DIH-1-2), (DIH-2-1) to (DIH-2-3), (DIH-3-1) to (DIH-3-6).

[0248]

[0249] In formula (DIH-1-2), m is an integer of 1 to 12.

[0250]

[0251]

[0252] Among the above-mentioned diamines, from the viewpoint of improving the residual image characteristics, it is preferable to use the compound represented by formula (DI-4-1), formula (DI-5-1), formula (DI-13), or formula (DI-17). In formula (DI-5-1), it is more preferable that m = 2 to 8, and it is further preferable that m = 4 to 8. Among the compound represented by formula (DI-13), it is preferable to use the compound represented by formula (DI-13-1). Among the compound represented by formula (DI-17), it is preferable to use the compound represented by formula (DI-17-1) or formula (DI-17-2). In formula (DI-17-1), it is more preferable that k = 2. As for the compound represented by formula (DI-17-2), it is preferable to use as a raw material of the polymer of the present application, especially in a manner (blended liquid crystal aligning agent to be described later) in which the polymer of the present application is used in combination with a polymer other than the polymer of the present application. It is more preferable that the compound represented by formula (DI-17-2) is e = 6 to 10, it is further preferable that e = 6, 8, or 10, and it is particularly preferable that e = 6.

[0253] In the raw material composition used as the raw material of the polymer of the present application, a part of the diamine compound can be substituted with at least one selected from the group consisting of a monoamine and a mono-hydrazide. As for the ratio of substitution, the ratio of at least one selected from the group consisting of a monoamine and a mono-hydrazide to the diamine compound is preferably in the range of 40 mol% or less. Such substitution can cause termination of the polymerization reaction at the time of generation of polyamic acid, and can inhibit further progress of the polymerization reaction. Therefore, by such substitution, the molecular weight of the obtained polymer (polyamic acid or a derivative thereof) can be easily controlled, and for example, the coating properties of the liquid crystal alignment agent can be improved without impairing the effects of the present application. The diamine compound which can be substituted with a monoamine or a mono-hydrazide can be one or two or more, without impairing the effects of the present application. As the monoamine, for example, aniline, 4-hydroxyaniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine, n-undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, n-octadecylamine, n-eicosylamine, p-aminophenyltrimethoxysilane, and 3-aminopropyltriethoxysilane can be given.

[0254] In the case where the polymer of the present application is polyamic acid or a derivative thereof, the raw material composition can further contain a mono-isocyanate compound as a monomer. By containing a mono-isocyanate compound in the monomer, the terminal of the obtained polyamic acid or a derivative thereof is modified, and the molecular weight is adjusted. By using the terminal-modified type of polyamic acid or a derivative thereof, for example, the coating properties of the liquid crystal alignment agent can be improved without impairing the effects of the present application. From the above viewpoint, the content of the mono-isocyanate compound in the monomer is preferably 1 to 10 mol% relative to the total amount of the diamine and the tetracarboxylic dianhydride in the monomer. As the mono-isocyanate compound, for example, phenyl isocyanate and naphthyl isocyanate can be given.

[0255] The liquid crystal alignment agent of the present application can be constituted of one polymer of the present application, or a polymer of the present application and a polymer other than the polymer of the present application can be mixed. Furthermore, in the present specification, the liquid crystal alignment agent constituted of one of the polymers is sometimes referred to as a single-layer type liquid crystal alignment agent. The liquid crystal alignment agent in which two or more of the polymers are mixed is sometimes referred to as a blend type liquid crystal alignment agent. The blend type liquid crystal alignment agent is particularly used in cases where voltage holding ratio (VHR) reliability, other electrical properties are valued.

[0256] As the polymer other than the polymer of the present application used in the blended liquid crystal alignment agent, any one or more of a polyamic acid and a polyamic acid derivative is preferable. As the polymer other than the polymer of the present application, as to the polyamic acid and the polyamic acid derivative, in addition to not containing the compound represented by formula (AN-2-1), formula (AN-2-2), formula (AN-2-4), or formula (AN-2-6) to formula (AN-2-8) as a raw material composition, reference can be made to the above description of the polymer of the present application.

[0257] The following describes the tetracarboxylic acid derivative preferable as a raw material of the polymer other than the polymer of the present application used in the blended liquid crystal alignment agent.

[0258] In the case where improvement in the transmittance of the liquid crystal display element is emphasized, a compound represented by formula (AN-1-1), formula (AN-1-2), formula (I-1), formula (AN-3-1), formula (AN-4-30), formula (AN-5-1), formula (AN-7-2), formula (AN-10-1), formula (AN-16-3), or formula (AN-16-4) is preferable, and in formula (AN-1-2), m = 4 or 8 is preferable.

[0259] In the case where improvement in the VHR of the liquid crystal display element is emphasized, a compound represented by formula (AN-1-1), formula (AN-1-2), formula (AN-3-1), formula (AN-4-5), formula (AN-4-30), formula (AN-7-2), formula (AN-10-1), formula (AN-16-3), formula (AN-16-4), formula (AN-16-17), or formula (I-1) is preferable, and in formula (AN-1-2), m = 4 or 8 is preferable.

[0260] Improvement in the relaxation speed of the residual charge (residual DC) in the liquid crystal alignment film by lowering the volume resistivity of the liquid crystal alignment film is effective as a method for preventing sticking. In the case where this object is emphasized, a compound represented by formula (AN-2-10), formula (AN-3-2), formula (AN-4-21), formula (AN-4-29), or formula (AN-11-3) is preferable.

[0261] Among them, a compound represented by formula (AN-1-1), formula (AN-2-10), formula (I-1), formula (AN-3-2), or formula (AN-4-21) is more preferable, and a compound represented by formula (AN-1-1), formula (AN-2-10), or formula (AN-3-2) is further preferable.

[0262] The following describes the diamine compound preferable as a raw material of the polymer other than the polymer of the present application used in the blended liquid crystal alignment agent.

[0263] In the case where improvement of liquid crystal alignment is emphasized, a compound represented by formula (DI-5-1), formula (DI-5-12), formula (DI-5-13) or formula (DI-7-3) is preferably used. In formula (DI-5-1), m = 2 to 8 is preferable, and m = 4 to 8 is more preferable. In formula (DI-5-12), m = 2 to 6 is preferable, and m = 5 is more preferable. In formula (DI-5-13), m = 1 or 2 is preferable, and m = 1 is more preferable.

[0264] In the case where improvement of transmittance is emphasized, a diamine represented by formula (DI-1-3), formula (DI-2-1), formula (DI-5-1), formula (DI-5-5), formula (DI-5-24) or formula (DI-7-3) is preferably used, and a compound represented by formula (DI-2-1) is more preferable. In formula (DI-5-1), m = 2 to 8 is preferable, and m = 8 is more preferable. In formula (DI-7-3), m = 2 or 3, n = 1 or 2 is preferable, and m = 3, n = 1 is more preferable.

[0265] In the case where improvement of VHR of a liquid crystal display element is emphasized, a compound represented by formula (DI-2-1), formula (DI-4-1), formula (DI-4-2), formula (DI-4-10), formula (DI-4-15), formula (DI-4-22), formula (DI-5-1), formula (DI-5-28), formula (DI-17-1) or formula (DI-13-1) is preferably used, and a diamine represented by formula (DI-2-1), formula (DI-5-1) or formula (DI-13-1) is more preferable. In formula (DI-5-1), m = 1 is preferable. In formula (DI-17-1), k = 2 is preferable.

[0266] Improvement of the relaxation speed of residual charge (residual DC) in a liquid crystal alignment film by lowering the volume resistivity of the liquid crystal alignment film is effective as a method for preventing sticking. In the case where this object is emphasized, a compound represented by formula (DI-4-1), formula (DI-4-2), formula (DI-4-10), formula (DI-4-15), formula (DI-5-1), formula (DI-5-12), formula (DI-5-13), formula (DI-5-28), formula (DI-4-20), formula (DI-4-21) or formula (DI-16-1) is preferably used, and a compound represented by formula (DI-4-1), formula (DI-5-1) or formula (DI-5-13) is more preferable. In formula (DI-5-1), m = 2 to 8 is preferable, and m = 4 to 8 is more preferable. In formula (DI-5-12), m = 2 to 6 is preferable, and m = 5 is more preferable. In formula (DI-5-13), m = 1 or 2 is preferable, and m = 1 is more preferable.

[0267] Among them, more preferably a compound represented by formula (DI-4-1), formula (DI-4-2), formula (DI-4-10), formula (DI-4-18), formula (DI-4-19), formula (DI-5-1), formula (DI-5-9), formula (DI-5-28), formula (DI-13-1), or formula (DIH-1-2), wherein, further preferably a compound represented by formula (DI-4-1), formula (DI-4-18), formula (DI-4-19), formula (DI-5-1) in which m = 1 or 2, formula (DI-5-9), formula (DI-13-1), or formula (DIH-1-2).

[0268] In the case of using a 2-component polymer, for example, there is a way of selecting a polymer having excellent properties of liquid crystal alignment ability on one side and a polymer having excellent properties of improving the electrical characteristics of a liquid crystal display element on the other side, and it is suitable for obtaining a liquid crystal alignment agent having a good balance between liquid crystal alignment properties and electrical characteristics.

[0269] In this case, by controlling the structure and molecular weight of each polymer, it is possible to cause the polymer having excellent properties of liquid crystal alignment ability to segregate to the upper layer of the film and the polymer having excellent properties of improving the electrical characteristics of a liquid crystal display element to segregate to the lower layer of the film in the process of dissolving these polymers in a solvent, coating the liquid crystal alignment agent on a substrate as described later, and performing pre-drying to form a thin film. Among the polymers present in a mixture, a polymer having a small surface energy can be separated to the upper layer and a polymer having a large surface energy can be separated to the lower layer. Confirmation of such layer separation can be confirmed by the surface energy of the formed liquid crystal alignment film being the same as or close to the surface energy of a film formed from a liquid crystal alignment agent containing only a polymer intended to segregate to the upper layer.

[0270] As a method of exhibiting layer separation, a method of reducing the molecular weight of a polymer intended to segregate to the upper layer can also be mentioned.

[0271] In a liquid crystal alignment agent composed of a mixture of a polyamic acid and a polyamic acid derivative, layer separation can also be exhibited by making the polymer intended to segregate to the upper layer a polyamic acid ester or a polyimide.

[0272] The polymer of the present application can be used as a raw material of a polymer segregating to the upper layer of the film, as a raw material of a polymer segregating to the lower layer of the film, and in addition, as a raw material of both, and is preferably used as a raw material of a polymer segregating to the upper layer of the film.

[0273] The polymer other than the polymer of the present application used in the above-mentioned blended liquid crystal alignment agent is preferably used as a polymer segregating to the lower layer of the film.

[0274] The proportion of the polyamic acid or the derivative thereof segregated in the upper layer of the film is preferably 5 to 80% by weight, and further preferably 20 to 80% by weight, relative to the total amount of the polyamic acid or the derivative thereof segregated in the upper layer of the film and the polyamic acid or the derivative thereof segregated in the lower layer of the film.

[0275] Further, the liquid crystal alignment agent of the present application can further contain a solvent from the viewpoint of the coating property of the liquid crystal alignment agent, adjustment of the concentration of the polyamic acid or the derivative thereof. The solvent can be used without particular limitation as long as it has a capability of dissolving the high molecular component. The solvent widely includes solvents generally used in the manufacturing process, use of the high molecular component such as polyamic acid, soluble polyimide, and the like, and can be appropriately selected according to the purpose of use. The solvent can be one kind or a mixed solvent of two or more kinds.

[0276] As the solvent, a mother solvent of the polyamic acid or the derivative thereof, and other solvents for the purpose of improving the coating property can be mentioned.

[0277] As the non-protic polar organic solvent which is a mother solvent of the polyamic acid or the derivative thereof, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethylimidazolidinone, N-methylcaprolactam, N-methylpropionamide, N,N-dimethylacetamide, dimethylsulfoxide, N,N-dimethylformamide, N,N-diethylformamide, diethylacetamide, N,N-dimethylisobutyramide, γ-butyrolactone, and γ-valerolactone, and the like can be mentioned. Among them, N-methyl-2-pyrrolidone, dimethylimidazolidinone, γ-butyrolactone, or γ-valerolactone is preferred.

[0278] As examples of the other solvents for the purpose of improving the coating property and the like, ethylene glycol monoalkyl ethers such as ethylene glycol monobutyl ether, ethylene glycol mono-tert-butyl ether; diethylene glycol monoalkyl ethers such as diethylene glycol monoethyl ether; diethylene glycol dialkyl ethers such as diethylene glycol ethyl methyl ether, diethylene glycol diethyl ether, diethylene glycol butyl methyl ether can be mentioned. Further, propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether, 1-butoxy-2-propanol; dipropylene glycol monoalkyl ethers such as dipropylene glycol monomethyl ether; triethylene glycol monoalkyl ethers, butyl cellosolve acetate, phenyl acetate, and ester compounds such as these acetates can be mentioned. Further, malonic acid dialkyl esters such as dimethyl malonate, alkyl lactate, diisobutyl ketone, diacetone alcohol, 3-methyl-3-methoxybutanol, 4-methyl-2-pentanol, diisobutyl carbinol, tetralin, and isophorone can be mentioned.

[0279] Among them, diisobutyl ketone, 4-methyl-2-pentanol, diisobutyl carbinol, ethylene glycol monobutyl ether, ethylene glycol mono-t-butyl ether, diethylene glycol monoethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol diethyl ether, diethylene glycol butyl methyl ether, 1-butoxy-2-propanol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, or butyl cellosolve acetate is preferred.

[0280] The concentration of the solid component in the liquid crystal alignment agent of the present application is not particularly limited, as long as an optimum value is selected depending on the various coating methods described below. Generally, in order to suppress unevenness, pinholes, and the like at the time of coating, 0.1 to 30% by weight, more preferably 1 to 10% by weight, relative to the weight of the varnish is preferred.

[0281] The viscosity of the liquid crystal alignment agent of the present application differs in the preferred range depending on the method of coating, the concentration of the polyamide acid or its derivative, the kind of polyamide acid or its derivative used, the kind and ratio of the solvent. For example, in the case of coating using a printer, 5 to 100 mPa-s (more preferably 10 to 80 mPa-s) is preferred. If it is 5 mPa-s or more, a sufficient film thickness is easily obtained, and if it is 100 mPa-s or less, printing unevenness is easily suppressed. In the case of coating using spin coating, 5 to 200 mPa-s (more preferably 10 to 100 mPa-s) is preferred. In the case of coating using an inkjet coating device, 5 to 50 mPa-s (more preferably 5 to 20 mPa-s) is preferred. The viscosity of the liquid crystal alignment agent is measured by a rotational viscosity measurement method, for example, using a rotational viscometer (TVE-20L type viscometer manufactured by Tokimec Inc.) (measurement temperature: 25°C).

[0282] The liquid crystal alignment agent of the present application can further contain various additives. In order to improve various properties of the liquid crystal alignment film, various additives can be used as selected depending on the respective purposes. Examples are shown below.

[0283] <Alkenyl-substituted Nadimide Compound>

[0284] For example, the liquid crystal alignment agent of the present application can further contain an alkenyl-substituted nematic imide compound from the viewpoint of long-term stabilization of the electrical properties of the liquid crystal display element. One or two or more kinds of alkenyl-substituted nematic imide compounds can be used. The content of the alkenyl-substituted nematic imide compound is preferably 1 to 50% by weight, more preferably 1 to 30% by weight, and further preferably 1 to 20% by weight, relative to the polyamic acid or its derivative, from the above viewpoint. The alkenyl-substituted nematic imide compound is preferably a compound that is soluble in a solvent in which the polyamic acid or its derivative used in the present application is dissolved. Preferred examples of the alkenyl-substituted nematic imide compound include the alkenyl-substituted nematic imide compounds disclosed in Japanese Patent Application Publication No. 2008-096979, Japanese Patent Application Publication No. 2009-109987, and Japanese Patent Application Publication No. 2013-242526. As particularly preferred examples of the alkenyl-substituted nematic imide compound, mention can be made of bis{4-(allyldicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide)phenyl}methane, N,N'-m-xylylene-bis(allyldicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide), or N,N'-hexamethylene-bis(allyldicyclo[2.2.1]hept-5-ene-2,3-dicarboxyimide).

[0285] <Compound having a radically polymerizable unsaturated double bond>

[0286] For example, the liquid crystal alignment agent of the present application can further contain a compound having a radically polymerizable unsaturated double bond from the viewpoint of long-term stabilization of the electrical properties of the liquid crystal display element. The compound having a radically polymerizable unsaturated double bond can be one compound or two or more kinds of compounds. Furthermore, the compound having a radically polymerizable unsaturated double bond does not include an alkenyl-substituted nematic imide compound. As preferred examples of the compound having a radically polymerizable unsaturated double bond, mention can be made of N,N'-methylenebisacrylamide, N,N'-dihydroxyethylidene-bisacrylamide, ethylene bisacrylate, 4,4'-methylenebis(N,N-dihydroxyethylacrylamide phenylamine), triallyl cyanurate, and the compounds having a radically polymerizable unsaturated double bond disclosed in Japanese Patent Application Publication No. 2009-109987, Japanese Patent Application Publication No. 2013-242526, International Publication No. 2014 / 119682, and International Publication No. 2015 / 152014. The content of the compound having a radically polymerizable unsaturated double bond is preferably 1 to 50% by weight, and more preferably 1 to 30% by weight, relative to the polyamic acid or its derivative, from the above viewpoint.

[0287] <Oxazine compound>

[0288] For example, the liquid crystal alignment agent of the present application can further contain an oxazoline compound from the viewpoint of long-term stabilization of the electrical characteristics of the liquid crystal display element. The oxazoline compound can be one compound or two or more compounds. The content of the oxazoline compound is preferably 0.1 to 50% by mass, more preferably 1 to 40% by mass, and further preferably 1 to 20% by mass, relative to the polyamic acid or the derivative thereof, from the above viewpoint.

[0289] The oxazoline compound is soluble in a solvent in which the polyamic acid or the derivative thereof is dissolved, and preferably has ring-opening polymerizability. As the preferred oxazoline compound, an oxazoline compound represented by formula (OX-3-1), formula (OX-3-9), formula (OX-3-10), and an oxazoline compound disclosed in Japanese Patent Laid-Open No. 2007-286597 and Japanese Patent Laid-Open No. 2013-242526 can be given.

[0290]

[0291] <oxazoline compound>

[0292] For example, the liquid crystal alignment agent of the present application can further contain an oxazoline compound from the viewpoint of long-term stabilization of the electrical characteristics of the liquid crystal display element. The oxazoline compound is a compound having an oxazoline structure. The oxazoline compound can be one compound or two or more compounds. The content of the oxazoline compound is preferably 0.1 to 50% by mass, more preferably 1 to 40% by mass, and further preferably 1 to 20% by mass, relative to the polyamic acid or the derivative thereof, from the above viewpoint. As the preferred oxazoline compound, an oxazoline compound disclosed in Japanese Patent Laid-Open No. 2010-054872 and Japanese Patent Laid-Open No. 2013-242526 can be given. More preferably, 1,3-bis(4,5-dihydro-2-oxazolyl)benzene can be given.

[0293] <epoxy compound>

[0294] For example, the liquid crystal alignment agent of the present application can further contain an epoxy compound from the viewpoint of long-term stabilization of the electrical characteristics of the liquid crystal display element, the viewpoint of increasing the hardness of the film, or the viewpoint of improving the adhesion to the sealing agent. The epoxy compound can be one compound or two or more compounds. The content of the epoxy compound is preferably 0.1 to 50% by mass, more preferably 1 to 20% by mass, and further preferably 1 to 10% by mass, relative to the polyamic acid or the derivative thereof, from the above viewpoint.

[0295] As the epoxy compound, various compounds having one or two or more epoxy rings in the molecule can be used.

[0296] For the purpose of improving the hardness of the film, or the purpose of improving the adhesion to the sealant, a compound having two or more epoxy rings in the molecule is preferable, and a compound having three or four epoxy rings is more preferable.

[0297] As the epoxy compound, the epoxy compounds disclosed in Japanese Patent Application Publication No. 2009-175715, Japanese Patent Application Publication No. 2013-242526, Japanese Patent Application Publication No. 2016-170409, and International Publication No. 2017 / 217413 can be given. As the preferable epoxy compound, N,N,N',N'-tetraglycidyl-4,4'-diaminodiphenylmethane, 3-glycidoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, (3,3',4,4'-epoxy) bicyclohexyl, 1,4-butanediol glycidyl ether, isocyanuric acid tris(2,3-epoxypropyl), 1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, or N,N,N',N'-tetraglycidyl-m-xylenediamine can be given. More preferably, 3-glycidoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane can be given. In addition to the above, an oligomer or a polymer having an epoxy ring can be added. The oligomer or the polymer having an epoxy ring can use the oligomer or the polymer disclosed in Japanese Patent Application Publication No. 2013-242526.

[0298] <silane compound>

[0299] For example, the liquid crystal aligning agent of the present application can further contain a silane compound for the purpose of improving the adhesion to the substrate and the sealant. The content of the silane compound is preferably 0.1 to 30% by weight, more preferably 0.5 to 20% by weight, and further preferably 0.5 to 10% by weight, relative to the polyamic acid or its derivative, for the above purpose.

[0300] As the silane compound, the silane coupling agents disclosed in Japanese Patent Application Publication No. 2013-242526, Japanese Patent Application Publication No. 2015-212807, Japanese Patent Application Publication No. 2018-173545, and International Publication No. 2018 / 181566 can be used. As the preferable silane coupling agent, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, p-aminophenyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-isocyanatepropyltriethoxysilane, or 3-ureidopropyltriethoxysilane can be given.

[0301] In addition to the above-described additives, from the viewpoint of improving the strength of the liquid crystal alignment film or the viewpoint of stabilizing the electrical characteristics of the liquid crystal display element over a long period of time, a compound having a cyclic carbonate group, a compound having a hydroxyalkylamide site, a hydroxyl group can also be added. As specific compounds, the compounds disclosed in Japanese Patent Application Publication No. 2016-118753, International Publication No. 2017 / 110976 can be given. As preferred compounds, the following formulas (HD-1) to (HD-4) can be given. These compounds are preferably 0.5 to 50% by weight, more preferably 1 to 30% by weight, and further preferably 1 to 10% by weight, with respect to the polyamic acid or the derivative thereof.

[0302]

[0303] Further, when charging prevention is required, an antistatic agent can be used, and when imidization is performed at a low temperature, an imidization catalyst can be used. As the imidization catalyst, the imidization catalyst disclosed in Japanese Patent Application Publication No. 2013-242526 can be given.

[0304] < Liquid crystal alignment film >

[0305] The liquid crystal alignment film of the present application is a film formed by heating the coated film of the above-described liquid crystal alignment agent of the present application. The liquid crystal alignment film of the present application can be obtained by a general method of producing a liquid crystal alignment film from a liquid crystal alignment agent. For example, the liquid crystal alignment film of the present application can be obtained by a process of forming a coated film of the liquid crystal alignment agent of the present application, a process of heating and drying, and a process of heating and baking. For the liquid crystal alignment film of the present application, a treatment for imparting anisotropy is performed. As the treatment, a rubbing treatment can also be performed to impart anisotropy, but it is preferable to impart anisotropy by light irradiation.

[0306] The method of forming a liquid crystal alignment film of the liquid crystal alignment agent for photoalignment of the present application will be described below.

[0307] The coated film can be formed by coating the liquid crystal alignment agent of the present application on a substrate of a liquid crystal display element, as in the production of a general liquid crystal alignment film. As the substrate, a glass substrate, a silicon nitride substrate, an acrylic substrate, a polycarbonate substrate, a polyimide substrate, or the like on which an electrode such as an ITO (Indium Tin Oxide) electrode, an IZO (In2O3-ZnO) electrode, an IGZO (In-Ga-ZnO4) electrode, a color filter, or the like can be provided can be given.

[0308] As a method of coating the liquid crystal alignment agent on a substrate, spin coating, printing, dipping, dropwise addition, inkjet, or the like is generally known. These methods can also be applied in the present application.

[0309] As for the heating drying step, methods in which heating treatment is performed in an oven or an infrared furnace, methods in which heating treatment is performed on a hot plate, and the like are generally known. The heating drying step is preferably performed at a temperature within a range in which the solvent can evaporate, and more preferably performed at a temperature that is relatively low with respect to the temperature in the heating baking step. Specifically, the heating drying temperature is preferably within a range of 30°C to 150°C, and further preferably within a range of 50°C to 120°C.

[0310] The heating baking step can be performed under conditions in which the polyamide acid or the derivative thereof exhibits a condition required for imidization reaction. Baking of the coating film is generally known as methods in which heating treatment is performed in an oven or an infrared furnace, methods in which heating treatment is performed on a hot plate, and the like. These methods can also be applied in the present application. It is generally preferable to perform at a temperature of about 90°C to 300°C, more preferably 120°C to 280°C, and further preferably 150°C to 250°C. The baking time is not particularly limited, and is preferably 1 minute to 2 hours, and more preferably 10 minutes to 40 minutes.

[0311] The heating can be performed in multiple stages, in which case the temperature can also be changed.

[0312] In order to orient the liquid crystal in one direction with respect to the horizontal and / or vertical direction, as a method of imparting anisotropy to the liquid crystal alignment film, a known photo-alignment method can be suitably used.

[0313] As the light used in the light irradiation step of the photo-alignment method, for example, ultraviolet rays or visible light containing light of a wavelength of 150 to 800 nm can be used. These lights are not particularly limited as long as they are capable of imparting liquid crystal alignment ability to the film, and in the case where a strong alignment restricting force is desired to be exhibited with respect to the liquid crystal, polarized light is preferable, and further linearly polarized light is preferable.

[0314] The wavelength of the polarized light in the above light irradiation step is preferably 150 to 400 nm, more preferably 200 to 400 nm, and further preferably 200 to 300 nm. The irradiation amount of the polarized light is preferably 0.001 to 10 J / cm 2 , and more preferably 0.1 to 5 J / cm 2 . The irradiation angle of the polarized light with respect to the film surface is not particularly limited, but in the case where a strong alignment restricting force is desired to be exhibited with respect to the liquid crystal, it is preferable to be as perpendicular as possible to the film surface from the viewpoint of shortening the alignment treatment time. Furthermore, the liquid crystal alignment film of the present application is capable of aligning the liquid crystal in a direction that is at a right angle with respect to the polarization direction of the linearly polarized light by irradiation of linearly polarized light.

[0315] As the light source used in the process of irradiating light, an ultrahigh-pressure mercury lamp, a high-pressure mercury lamp, a low-pressure mercury lamp, a deep UV lamp, a halogen lamp, a metal halide lamp, a high-power metal halide lamp, a xenon lamp, a mercury-xenon lamp, an excimer lamp, a KrF excimer laser, a fluorescent lamp, an LED lamp, a sodium lamp, a microwave-excited electrodeless lamp, or the like can be used without any limitation.

[0316] In order to improve the liquid crystal alignment ability of the liquid crystal alignment film, light irradiation can be performed while heating the liquid crystal alignment film. In this case, the heating temperature is preferably in the range of 50°C to 250°C.

[0317] The light irradiation process can be performed after the heat drying process or after the heat baking process, and is preferably performed after the heat baking process. Alternatively, the light irradiation process can be performed simultaneously with the heat drying process.

[0318] The liquid crystal alignment film of the present application is preferably subjected to additional heating after the light irradiation process. The heating temperature is performed at the same temperature as or a higher temperature than that of the heat baking process, and is preferably in the range of 150°C to 300°C, more preferably in the range of 150°C to 250°C, and further preferably in the range of 200°C to 250°C. The time for the additional heating is preferably in the range of 5 minutes to 2 hours, more preferably in the range of 5 minutes to 60 minutes, and further preferably in the range of 5 minutes to 30 minutes.

[0319] In addition, a cleaning process can be provided after the light irradiation process or after the additional heating process. Specifically, the liquid crystal alignment film is immersed in a solvent. The temperature at the time of immersion is preferably in the range of 10°C to 80°C, and more preferably in the range of 20°C to 50°C. In addition, ultrasonic treatment is preferably performed. The treatment time is preferably in the range of 1 minute to 1 hour, and more preferably in the range of 1 minute to 30 minutes. The solvent used is not particularly limited as long as it is a solvent that dissolves the decomposition product generated from the liquid crystal alignment film by ultraviolet irradiation, and water, methanol, ethanol, 2-propanol, acetone, methyl ethyl ketone, 1-methoxy-2-propanol, 1-methoxy-2-propanol acetate, butyl cellosolve, ethyl lactate, methyl lactate, diacetone alcohol, methyl 3-methoxypropionate, ethyl 3-ethoxypropionate, propyl acetate, butyl acetate, or cyclohexyl acetate, or the like can be mentioned. Among them, from the viewpoint of versatility and safety, water, 2-propanol, 1-methoxy-2-propanol, or ethyl lactate is preferred. After the immersion, heating or rinsing is preferably performed. Alternatively, both of them can be performed. The heating temperature is preferably in the range of 150°C to 300°C, and more preferably in the range of 200°C to 230°C. The heating time is preferably in the range of 10 seconds to 30 minutes, and more preferably in the range of 1 minute to 10 minutes. In the rinsing, a low-boiling-point solvent such as water, methanol, ethanol, 2-propanol, acetone, or methyl ethyl ketone is preferably used.

[0320] The film thickness of the liquid crystal alignment film of the present application is not particularly limited, and is preferably 10 to 300 nm, more preferably 30 to 150 nm. The film thickness of the liquid crystal alignment film of the present application can be measured by a publicly known film thickness measuring device such as a step meter or an ellipsometer.

[0321] The liquid crystal alignment film of the present application can be suitably used for the alignment control of a liquid crystal composition in a liquid crystal display element. In addition to the alignment of a liquid crystal composition in a liquid crystal display element, it can also be used for the alignment control of a liquid crystal material in all other liquid crystal elements such as a liquid crystal antenna, a light control window, an optical compensation material, a variable phase shifter, and the like.

[0322] < Liquid crystal display element >

[0323] Next, the liquid crystal display element of the present application will be described. The liquid crystal display element of the present application is characterized by having the liquid crystal alignment film of the present application, and can realize a liquid crystal display element with excellent display quality.

[0324] The liquid crystal display element of the present application will be described in detail. The present application is a liquid crystal display element having a pair of substrates disposed in opposition to each other, an electrode formed on one or both of the opposing surfaces of each of the pair of substrates, a liquid crystal alignment film formed on the opposing surfaces of each of the pair of substrates, a liquid crystal layer formed between the pair of substrates, a pair of polarizing films disposed in a manner sandwiching the substrates in opposition to each other, a backlight, and a driving device, wherein the liquid crystal alignment film is composed of the liquid crystal alignment film of the present application.

[0325] The electrode is not particularly limited as long as it is an electrode formed on one surface of a substrate. As such an electrode, for example, an ITO, an evaporation film of a metal, or the like can be given. Further, the electrode can be formed on the entire surface of one surface of a substrate, and can also be formed in a desired shape in a pattern. As the desired shape of the electrode, for example, a comb shape or a zigzag structure, or the like can be given. The electrode can be formed on one of the pair of substrates, or can be formed on both of the substrates. The formation method of the electrode differs depending on the type of the liquid crystal display element, and, for example, in the case of an IPS (In-Plane Switching) type liquid crystal display element (a transverse electric field type liquid crystal display element), the electrode is disposed on one of the pair of substrates, and in the case of other liquid crystal display elements, the electrode is disposed on both of the pair of substrates. The liquid crystal alignment film is formed on the substrate or the electrode.

[0326] The liquid crystal layer is formed in a manner that the pair of substrates having the liquid crystal alignment film formed on the surfaces thereof sandwich a liquid crystal composition. In the formation of the liquid crystal layer, a spacer such as a microparticle or a resin sheet can be used as necessary to form an appropriate gap between the pair of substrates.

[0327] As a method of forming a liquid crystal layer, a vacuum injection method and an ODF (One Drop Fill) method are known.

[0328] In the vacuum injection method, a gap (cell gap) is provided in a manner that the liquid crystal alignment film surfaces face each other, and a liquid crystal injection port is left, a sealant is printed, and substrates are attached. After a liquid crystal is injected into the cell gap divided by the substrate surfaces and the sealant by using a vacuum differential pressure, the injection port is sealed, thereby manufacturing a liquid crystal display element.

[0329] In the ODF method, a sealant is printed on the outer periphery of the liquid crystal alignment film surface of one of a pair of substrates, and a liquid crystal is dropped on the area inside the sealant, and then the other substrate is attached in a manner that the liquid crystal alignment film surfaces face each other. Then, the liquid crystal is pushed to the entire surface of the substrate, and then ultraviolet light is irradiated to the entire surface of the substrate to cure the sealant, thereby manufacturing a liquid crystal display element.

[0330] As the sealant used in the attachment of the substrates, a heat-curing type other than a UV-curing type is known. The printing of the sealant can be performed by, for example, a screen printing method.

[0331] As the liquid crystal composition, various liquid crystal compositions having a positive or negative dielectric anisotropy can be used without particular limitation. As the preferred liquid crystal composition having a positive dielectric anisotropy, liquid crystal compositions disclosed in Japanese Patent No. 3086228, Japanese Patent No. 2635435, Japanese Patent Laid-Open No. 5-501735, Japanese Patent Laid-Open No. 8-157826, Japanese Patent Laid-Open No. 8-231960, Japanese Patent Laid-Open No. 9-241644 (EP 885272 A1), Japanese Patent Laid-Open No. 9-302346 (EP 806466 A2), Japanese Patent Laid-Open No. 8-199168 (EP 722998 A1), Japanese Patent Laid-Open No. 9-235552, Japanese Patent Laid-Open No. 9-255956, Japanese Patent Laid-Open No. 9-241643 (EP 885271 A1), Japanese Patent Laid-Open No. 10-204016 (EP 844229 A1), Japanese Patent Laid-Open No. 10-204436, Japanese Patent Laid-Open No. 10-231482, Japanese Patent Laid-Open No. 2000-087040, Japanese Patent Laid-Open No. 2001-48822, and the like can be exemplified.

[0332] As preferred examples of the liquid crystal composition having the negative dielectric anisotropy, there can be mentioned the liquid crystal compositions disclosed in Japanese Patent Laid-Open No. 57-114532, Japanese Patent Laid-Open No. 2-4725, Japanese Patent Laid-Open No. 4-224885, Japanese Patent Laid-Open No. 8-40953, Japanese Patent Laid-Open No. 8-104869, Japanese Patent Laid-Open No. 10-168076, Japanese Patent Laid-Open No. 10-168453, Japanese Patent Laid-Open No. 10-236989, Japanese Patent Laid-Open No. 10-236990, Japanese Patent Laid-Open No. 10-236992, Japanese Patent Laid-Open No. 10-236993, Japanese Patent Laid-Open No. 10-236994, Japanese Patent Laid-Open No. 10-237000, Japanese Patent Laid-Open No. 10-237004, Japanese Patent Laid-Open No. 10-237024, Japanese Patent Laid-Open No. 10-237035, Japanese Patent Laid-Open No. 10-237075, Japanese Patent Laid-Open No. 10-237076, Japanese Patent Laid-Open No. 10-237448 (EP 967261 Al), Japanese Patent Laid-Open No. 10-287874, Japanese Patent Laid-Open No. 10-287875, Japanese Patent Laid-Open No. 10-291945, Japanese Patent Laid-Open No. 11-029581, Japanese Patent Laid-Open No. 11-080049, Japanese Patent Laid-Open No. 2000-256307, Japanese Patent Laid-Open No. 2001-019965, Japanese Patent Laid-Open No. 2001-072626, Japanese Patent Laid-Open No. 2001-192657, Japanese Patent Laid-Open No. 2010-037428, International Publication No. 2011 / 024666, International Publication No. 2010 / 072370, Japanese Patent Publication No. 2010-537010, Japanese Patent Laid-Open No. 2012-077201, Japanese Patent Laid-Open No. 2009-084362, and the like.

[0333] One or more optically active compounds can also be added to the liquid crystal composition having a positive or negative dielectric anisotropy.

[0334] Further, for example, with respect to the liquid crystal composition used in the liquid crystal display element of the present application, an additive can be further added, for example, from the viewpoint of improving the alignment properties. Such an additive is a photopolymerizable monomer, an optically active compound, an antioxidant, an ultraviolet absorber, a pigment, an antifoaming agent, a polymerization initiator, a polymerization inhibitor, or the like. As the preferred photopolymerizable monomer, optically active compound, antioxidant, ultraviolet absorber, pigment, antifoaming agent, polymerization initiator, and polymerization inhibitor, the compounds disclosed in International Publication No. 2015 / 146330 and the like can be mentioned.

[0335] For a liquid crystal display element suitable for a PSA (polymer sustained alignment) mode, a polymerizable compound can be mixed in the liquid crystal composition. Preferred examples of the polymerizable compound are acrylate, methacrylate, vinyl compound, vinyloxy compound, propenyl ether, epoxy compound (oxirane, oxetane), vinyl ketone, and the like, which have a polymerizable group. As the preferred compound, the compounds disclosed in International Publication No. 2015 / 146330 and the like can be mentioned.

[0336] Examples

[0337] The present application is illustrated below with examples. Further, the evaluation methods and compounds used in the examples are described below.

[0338] Weight average molecular weight (Mw)

[0339] With respect to the weight average molecular weight of the polyamic acid, the GPC method was performed using a 2695 separation module · 2414 differential refractive detector (manufactured by Waters Corporation) and was calculated by polystyrene conversion. The obtained polyamic acid was diluted with a phosphoric acid-DMF mixed solution (phosphoric acid / DMF = 0.6 / 100 by weight) to a polyamic acid concentration of about 2% by weight. The mixed solution was used as a developing agent, and the measurement was performed at a column temperature of 50°C and a flow rate of 0.40 mL / min using an HSPgel RT MB-M (manufactured by Waters Corporation). The standard polystyrene was TSK standard polystyrene manufactured by Tosoh Corporation.

[0340] Sealing adhesion evaluation

[0341] The end of the upper and lower substrates of the sample for sealing adhesion measurement described later was fixed on a table type precision universal testing machine AGS-X 500N manufactured by Shimadzu Corporation, and the pressure at the time of peeling was measured by pressing from the upper part of the center of the substrate. Then, the adhesion strength (N / cm2) was calculated by dividing the area (cm2) estimated from the diameter of the measured sealant by the pressure (N). 2 2 ​). It can be said that the greater the value of the adhesion strength, the higher the adhesion to the sealant. The adhesion strength of the liquid crystal alignment film used as a reference was divided by the calculated adhesion strength, and the sealing adhesion of each liquid crystal alignment film was compared.

[0342] < tetracarboxylic dianhydride >

[0343]

[0344] < diamine >

[0345]

[0346] < solvent >

[0347] NMP: N-methyl-2-pyrrolidone

[0348] BC: butyl cellosolve (ethylene glycol monobutyl ether)

[0349] < additive >

[0350] Additive 1: 1,3-bis(4,5-dihydro-2-oxazolyl)benzene

[0351] Additive 2: (3,3',4,4'-dihydroxy)bis cyclohexane

[0352] Preparation of varnish

[0353] [Preparation Example 1 of varnish] Preparation of varnish Al

[0354] In a 100 mL three-necked flask equipped with a stirring blade and a nitrogen inlet tube, 1.941 g of a compound represented by the formula (DI-17-1), k = 2 and 0.776 g of a compound represented by the formula (DI-4-1) were added, and 34.0 g of NMP was added to stir. To this solution, 2.736 g of a compound represented by the formula (I-2) and 0.547 g of a compound represented by the formula (AN-2-2), m = 2 were added under a nitrogen atmosphere, and stirred at room temperature for 12 hours. To this, 30.0 g of NMP and 30.0 g of BC were added, and the solution was heated and stirred at 60°C until the weight average molecular weight of the solute polymer reached the desired weight average molecular weight, to obtain a varnish Al having a weight average molecular weight of the solute of about 35,000 and a resin component concentration (solid component concentration) of 6% by weight.

[0355] [Preparation Examples 2 to 14 of varnish] Preparation of varnishes A2 to A9, varnishes R1 to R3, varnishes B1 and B2

[0356] Varnishes A2 to A9, varnishes Rl to R3 having a resin component concentration of 6% by weight were produced in the same manner as in Production Example 1 except that the compounds used as the diamine and tetracarboxylic dianhydride were changed as shown in Table 1. Further, varnishes Bl, B2 were produced in the same manner as in Production Example 1 except that the compounds used as the diamine and tetracarboxylic dianhydride were changed as shown in Table 2. Further, in Table 1, in the production examples in which two or more compounds are described as the diamine, it means that all of the compounds are used as the diamine, and in the production examples in which two or more compounds are described as the tetracarboxylic dianhydride, it means that all of the compounds are used as the tetracarboxylic dianhydride. The values in the brackets indicate the blending ratio (mole %), and the blank indicates that the compound corresponding to the column is not used.

[0357] [Table 1]

[0358]

[0359] [Table 2]

[0360]

[0361] [Example 1]

[0362] A liquid crystal alignment agent 1 was produced by diluting and stirring the varnish Al with an NMP-BC mixed solution (NMP / BC = 7 / 3 by weight) so that the solid content concentration became 4% by weight. Two glass substrates of the same size were prepared. On one of the glass substrates, the produced liquid crystal alignment agent was applied by a spin coating method. After the application, the substrate was heated at 60°C for 80 seconds to evaporate the solvent, and then subjected to a baking treatment at 230°C for 30 minutes to form a liquid crystal alignment film. A linearly polarized light of ultraviolet rays was irradiated from a direction perpendicular to the substrate via a polarizing plate of a wavelength region of 230 nm to 310 nm using a multiple light ML-501C / B manufactured by Bunkou Electric Machine Co., Ltd. At this time, the exposure time of the linearly polarized light was adjusted so that the light quantity at a wavelength of 254 nm was 0.3 ± 0.03 J / cm 2 at a wavelength of 254 nm. Then, additional heating was performed at 230°C for 30 minutes.

[0363] A sealant (XN-1500T manufactured by Kyocera Chemical Industries Corporation) in which bead-shaped spacers having a diameter of 5 μm were dispersed was dropped on the surface of the substrate on which the alignment film was formed. Subsequently, a glass substrate on which no alignment agent was applied was used for lamination so that the overlapping width of the substrates became 1 cm with the sealant interposed therebetween. At this time, the amount of dropping of the sealant was adjusted so that the diameter of the sealant after the lamination became about 3 mm. After the two laminated substrates were fixed with a jig, 3 J / cm 2A sample for the sealing adhesion evaluation was prepared by UV irradiation followed by heating at 120°C for 1 hour to cure the sealing agent.

[0364] A comparative alignment agent 1 was prepared by using varnish R1 instead of varnish Al, and a sample for the sealing adhesion evaluation was prepared by the same procedure. The adhesion strength was calculated by the evaluation method described above.

[0365] The adhesion strength of the alignment film formed from the liquid crystal alignment agent 1 was divided by the adhesion strength of the alignment film formed from the comparative alignment agent 1, and the proportion of the adhesion strength based on the comparative alignment agent 1 was calculated, and the result was that the proportion was 1.3.

[0366] [Examples 2] to [Example 9], [Comparative Examples 1] to [Comparative Example 3]

[0367] The liquid crystal alignment agents 2 to 9 and comparative alignment agents 1 to 3 were prepared by using the varnishes shown in Table 3 instead of varnish Al, and otherwise in the same manner as in Example 1, and the adhesion strength of the alignment film formed with respect to the sealing agent was measured for each. The proportion was calculated by dividing the adhesion strength by the adhesion strength of the alignment film formed from the comparative alignment agent 1. The varnishes used and the adhesion strengths (proportions) are shown in Table 3 together with the results of Example 1.

[0368] [Table 3]

[0369] Varnish Adhesion strength (ratio) Example 1 Liquid crystal alignment agent 1 A1 1.3 Example 2 Liquid crystal alignment agent 2 A2 1.4 Example 3 Liquid crystal alignment agent 3 A3 1.3 Example 4 Liquid crystal alignment agent 4 A4 1.6 Example 5 Liquid crystal alignment agent 5 A5 1.5 Example 6 Liquid crystal alignment agent 6 A6 1.4 Example 7 Liquid crystal alignment agent 7 A7 1.2 Example 8 Liquid crystal alignment agent 8 A8 1.5 Example 9 Liquid crystal alignment agent 9 A9 1.5 Comparative example 1 Comparative alignment agent 1 R1 1.0 Comparative example 2 Comparative alignment agent 2 R2 0.9 Comparative example 3 Comparative alignment agent 3 R3 1.0

[0370] [Example 10]

[0371] A liquid crystal alignment agent 10 was prepared by blending varnish A8 and varnish Bl so that the weight ratio was 6:4, and diluting and stirring with an NMP-BC mixed solution (NMP / BC = 7 / 3 by weight) so that the solid content concentration was 3.7% by weight.

[0372] The same operation as in Example 1 was performed using the liquid crystal alignment agent 10, and the adhesion strength (proportion) was calculated.

[0373] [Example 11]

[0374] A liquid crystal alignment agent 11 was prepared by using the varnishes shown in Table 4 instead of varnish A8 and varnish Bl, and otherwise in the same manner as in Example 10. The adhesion strength (proportion) was calculated in the same manner as in Example 10 using the prepared liquid crystal alignment agent. The varnishes used, the blending ratio, and the adhesion strength (proportion) are shown in Table 4 together with Example 10.

[0375] [Table 4]

[0376]

[0377] As shown in Tables 3 and 4, in Examples 1 to 11, the adhesion strength (ratio) was 1.2 to 1.8, and by using at least one compound selected from the group consisting of Formula (AN-2-1), Formula (AN-2-2), Formula (AN-2-4), and Formula (AN-2-6) to Formula (AN-2-8), a liquid crystal alignment film having high sealing adhesion can be produced.

[0378] Industrial applicability

[0379] If the liquid crystal alignment agent for photo-alignment of the present application is used, a liquid crystal alignment film exhibiting high sealing adhesion can be produced. The liquid crystal alignment agent for photo-alignment of the present application can be suitably applied to a horizontal electric field type liquid crystal display element.

Claims

1. A liquid crystal alignment agent comprising a polyamic acid or a derivative thereof obtained by reacting a tetracarboxylic acid derivative with a diamine-based compound, wherein the liquid crystal alignment agent comprises a compound represented by Formula (I), and at least one selected from the group consisting of Formula (AN-2-1), Formula (AN-2-2), Formula (AN-2-4), and Formula (AN-2-6) to Formula (AN-2-8) as the tetracarboxylic acid derivative, in Formula (I), *1, *1', *2, and *2' are binding bonds, each independently bonded to a hydroxyl group, a chlorine atom, or an alkoxy group having a carbon number of 1 to 6, and at least one of the group of *1 and *1' and the group of *2 and *2' can be bonded to the same oxygen atom; R b1 , R b2 , R b3 , and R b4 are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, a monovalent organic group having 1 to 6 carbon atoms containing a fluorine atom, or a phenyl group; in Formula (AN-2-2), m is an integer of 1 to 12.

2. The liquid crystal alignment agent according to claim 1, wherein the at least one selected from the group consisting of the Formula (AN-2-1), Formula (AN-2-2), Formula (AN-2-4), and Formula (AN-2-6) to Formula (AN-2-8) is at least one selected from the group consisting of Formula (AN-2-1), Formula (AN-2-2), and Formula (AN-2-4), in Formula (AN-2-2), m is an integer of 1 to 12.

3. The liquid crystal alignment agent according to claim 1, wherein the at least one selected from the group consisting of the Formula (AN-2-1), Formula (AN-2-2), Formula (AN-2-4), and Formula (AN-2-6) to Formula (AN-2-8) is Formula (AN-2-2), in Formula (AN-2-2), m is an integer of 1 to 12.

4. The liquid crystal alignment agent according to claim 1, wherein the diamine-based compound comprises at least one selected from the group consisting of Formula (DI-4-1), Formula (DI-5-1), Formula (DI-13), and Formula (DI-17), in Formula (DI-5-1), m is an integer of 1 to 12; In formula (DI-13), R 23 independently an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or -Cl, p and q are each independently an integer of 0 to 4; In formula (DI-17), R 23 independently an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, or -Cl, p is independently an integer of 0 to 4, R 25 independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or tert-butoxycarbonyl, Z is a divalent group including an alkylene group having 1 to 10 carbon atoms, at least one CH2in the alkylene group having 1 to 10 carbon atoms can be replaced with NH, but NH is not adjacent.

5. The liquid crystal alignment agent according to any one of claims 1 to 4, wherein the liquid crystal alignment agent comprises a polyamic acid or a derivative thereof obtained by reacting a tetracarboxylic acid derivative other than the compound represented by Formula (AN-2-1), Formula (AN-2-2), Formula (AN-2-4), or Formula (AN-2-6) to Formula (AN-2-8) with a diamine-based compound.

6. A liquid crystal alignment film formed from the liquid crystal alignment agent according to any one of claims 1 to 5.

7. A liquid crystal element having the liquid crystal alignment film according to claim 6.

8. A method for manufacturing a liquid crystal alignment film, comprising: a step of applying the liquid crystal alignment agent according to any one of claims 1 to 5 to a substrate; a step of performing firing on the substrate; and a step of irradiating polarized ultraviolet rays to the substrate. ​

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