JP6904216B2 - A liquid crystal alignment agent for forming a liquid crystal alignment film, a liquid crystal alignment film, and a liquid crystal display element using the same. - Google Patents

Description

The present invention relates to a liquid crystal alignment agent containing a polyamic acid or a derivative thereof and a specific compound, a liquid crystal alignment film formed by using the liquid crystal alignment agent, and a liquid crystal display element having the liquid crystal alignment film.

Various display devices such as personal computer monitors, LCD TVs, video camera viewfinders, and projection displays, as well as optelectronics-related elements such as optical printer heads, optical Fourier conversion elements, and light valves, have been commercialized today. The mainstream of liquid crystal display elements on the market is a display element using a nematic liquid crystal. As a display method of the nematic liquid crystal display element, a TN (Twisted Nematic) mode and an STN (Super Twisted Nematic) mode are well known. In recent years, in order to improve the narrow viewing angle, which is one of the problems of these modes, a TN type liquid crystal display element using an optical compensation film, and MVA (Multi) that combines vertical orientation and protrusion structure technology. -Domain Vertical Alignment) mode, horizontal electric field type IPS (In-Plane Switching) mode, FFS (Fringe Field Switching) mode, etc. have been proposed and put into practical use.

The technological development of liquid crystal display elements has been achieved not only by improving these drive systems and element structures, but also by improving the constituent members used in the elements. Among the constituent members used in the liquid crystal display element, the liquid crystal alignment film is one of the important materials related to the display quality, and the performance of the alignment film can be improved as the quality of the liquid crystal display element is improved. It's becoming important.

The liquid crystal alignment film is formed of a liquid crystal alignment agent. Currently, the liquid crystal alignment agent mainly used is a solution (varnish) in which a polyamic acid, a polyamic acid ester, a polyimide, or the like is dissolved in an organic solvent. After applying this solution to the substrate, a film is formed by means such as heating to form a polyimide-based liquid crystal alignment film. After the film is formed, an orientation treatment suitable for the above-mentioned display mode is performed as necessary.

Industrially, a rubbing method that is simple and capable of high-speed processing of a large area is widely used as an orientation processing method. The rubbing method is a process of rubbing the surface of the liquid crystal alignment film in one direction using a cloth on which fibers such as nylon, rayon, and polyester are transplanted, which makes it possible to obtain a uniform orientation of the liquid crystal molecules. However, problems such as dust generation and static electricity generation by the rubbing method have been pointed out. The orientation treatment method by rubbing is still continuously used in the manufacturing process of liquid crystal display elements, but in recent years, an orientation treatment method to replace it has been actively developed.

An orientation treatment method that is attracting attention as an alternative orientation treatment method to the rubbing method is a photoalignment treatment method that irradiates light to perform orientation treatment. Many alignment mechanisms such as a photodecomposition method, a photoisomerization method, a photodimerization method, and a photocrosslinking method have been proposed for the photoalignment treatment method (see, for example, Non-Patent Document 1, Patent Documents 1 and 2). The optical orientation method has higher alignment uniformity than the rubbing method, and because it is a non-contact orientation treatment method, the film is not scratched, causing display defects such as dust generation and static electricity on the liquid crystal display element. There are advantages such as reduction.

On the other hand, in order to apply the liquid crystal alignment agent (varnish) on the substrate, a printing method is industrially used. Examples of the printing method of the liquid crystal alignment agent include flexographic printing and inkjet printing. Inkjet printing is becoming the mainstream for printing on large-area substrates of the 6th generation and above.

However, when the varnish is ejected as droplets on the substrate by using the inkjet method to form a coating film, there may be a problem that unevenness occurs in the plane along the scanning direction of the outlet (nozzle). The causes of this in-plane unevenness are (1) the droplets do not sufficiently wet and spread with respect to the substrate, (2) the leveling property of the ejected droplets is poor, and the solute component (solid content) is uneven. It is conceivable that the solvent precipitates, (3) the solvent having good wettability dries quickly, and the applied solution shrinks during drying (see, for example, Patent Document 3).

Under these circumstances, the use of diisobutyl ketone, which imparts low surface tension, is disclosed as a solvent used for inkjet printing in order to solve in-plane unevenness (see, for example, Patent Document 4).

However, since the polymer has low solubility in diisobutyl ketone, cloudiness and precipitation of solid content are likely to occur. Such white turbidity and precipitation of solid content cause clogging of the nozzle of the discharge head.

JP-A-9-297313 Japanese Patent Application Laid-Open No. 10-251646 JP-A-2009-063797 International release 2009/107406

Liquid crystal, Volume 3, Issue 4, page 262, 1999

An object of the present invention is to provide a liquid crystal aligning agent used when printing a coating film for a liquid crystal alignment film by an inkjet method, in which polymer solids do not precipitate and in-plane unevenness does not occur in the coating film. is there. Another object of the present invention is to provide a liquid crystal alignment film formed by using the liquid crystal alignment agent, and further to provide a liquid crystal display element having the liquid crystal alignment film.

As a result of diligent studies, the present inventors have made a solvent "4-methyl-2-pentanol" which has high solubility of the polymer forming the alignment film described later, has good wettability and spread, and can prevent in-plane unevenness of the coating film. And completed the present invention.

The present invention comprises the following.
[1] A liquid crystal alignment agent containing at least one polymer and a solvent selected from the group consisting of polyamic acids and derivatives thereof, wherein the solvent contains 4-methyl-2-pentanol.

[2] The liquid crystal alignment agent according to item [1], wherein the ratio of 4-methyl-2-pentanol in the solvent is 0.1 to 20% by weight.

[3] At least one selected from the group consisting of N-methyl-2-pyrrolidone, γ-butyrolactone, 1,3-dimethyl-2-imidazolidinone, and N-ethyl-2-pyrrolidone as a good solvent in the solvent. The liquid crystal alignment agent according to item [1] or item [2], which contains one.

[4] The solvent contains at least one selected from the group consisting of butyl cellosolve, 1-butoxy-2-propanol, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, and diethylene glycol butyl methyl ether as a poor solvent [1]. The liquid crystal aligning agent according to any one of [3].

[5] Any one of [1] to [4], wherein the ratio of the good solvent in the solvent is 20 to 89% by weight, and the ratio of the poor solvent is 10 to 60% by weight with respect to the total solvent weight. The liquid crystal alignment agent according to the section.

[6] A method for forming a liquid crystal alignment film, which comprises a step of applying the liquid crystal alignment agent according to any one of [1] to [5] to a substrate by an inkjet method.

[7] Formation of a liquid crystal alignment film including a step of applying the liquid crystal alignment agent according to any one of [1] to [5] to a substrate to form a coating film, and a step of irradiating the coating film with ultraviolet rays. Method.

[8] A pair of substrates arranged to face each other, a group of electrodes formed on one or both of the facing surfaces of the pair of substrates, and a plurality of active elements connected to the group of electrodes. In a method for manufacturing a liquid crystal display element having a liquid crystal alignment film formed on the facing surfaces of the pair of substrates and a liquid crystal layer formed between the pair of substrates.
A method for manufacturing a liquid crystal display element, wherein the liquid crystal alignment film is formed by the method according to item [6] or [7].

The liquid crystal alignment agent using a solvent containing 4-methyl-2-pentanol, which has high polymer solubility, improves wet spread and prevents in-plane unevenness of the coating film. The liquid crystal alignment agent of the present invention is particularly suitable for inkjet printing applications.

The main body of the present invention is a liquid crystal alignment agent containing at least one polymer selected from the group consisting of polyamic acids and derivatives thereof and a solvent, which is characterized by containing 4-methyl-2-pentanol in the solvent. It is a liquid crystal alignment agent. The solvent used in the liquid crystal alignment agent of the present invention is divided into the following three groups: a good solvent, a poor solvent, and a third solvent.

The good solvent is selected from the group of polar organic solvents in which the polymer forming the alignment film has high solubility.

Specific examples of such polar organic solvents include N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethylimidazolidinone, N-methylcaprolactam, N-methylpropionamide, N, N-dimethylacetamide, These are lactones such as dimethyl sulfoxide, N, N-dimethylformamide, N, N-diethylformamide, diethylacetamide, and γ-butyrolactone.

Among these solvents, the solvents in which the polymer shows particularly high solubility are N-methyl-2-pyrrolidone, γ-butyrolactone, 1,3-dimethyl-2-imidazolidinone, and N-ethyl-2-pyrrolidone. ..

The poor solvent has low solubility of the polymer, but has a relatively small surface energy of less than 30 mN / m and is characterized by good wettability to a substrate. Specific examples thereof include alcohols and ethers.

Specific examples of alcohols include butyl cellosolve (ethylene glycol monobutyl ether), ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, propylene glycol monopropyl ether, 1-. Butoxy-2-propanol, ethyl lactate, methyl lactate, propyl lactate.

Specific examples of ethers include ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, diethylene glycol ethyl propyl ether, diethylene glycol butyl methyl ether, diethylene glycol propyl methyl ether, diethylene glycol butyl ethyl ether, and propylene glycol. Monoethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, propylene glycol monomethyl ether propionate.

Among these, solvents having a relatively low surface energy and good wettability to a substrate are butyl cellosolve, 1-butoxy-2-propanol, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, and diethylene glycol butyl methyl ether.

The third solvent is a solvent that improves the wettability and spreadability of the solution. By mixing this solvent, in-plane unevenness of the coating film can be prevented.

Specific examples of such a solvent include diisobutyl ketone, 4-methyl-2-pentanol, and dipentyl ether. Among these, the solvents that are more excellent in the wettability of the solution are diisobutyl ketone and 4-methyl-2-pentanol. Further, considering the solubility of the polymer, 4-methyl-2-pentanol is particularly preferable.

Since each of these three types of solvents has different characteristics, it is important to have the composition ratio described below.

The ratio of the good solvent to the total solvent is 20 to 89% by weight, a preferable ratio is 30 to 84% by weight, and a more preferable ratio is 45 to 75% by weight.

A good solvent is used at a ratio of 20% by weight or more with respect to the total solvent in order to prevent the precipitation of the polymer in the solution, the clogging of the nozzle and head of the inkjet device, and the occurrence of in-plane unevenness of the coating film. On the contrary, in order to prevent deterioration of printability due to a decrease in the amount of the poor solvent, it is used in a ratio of 89% by weight or less with respect to the total solvent.

The ratio of the poor solvent to the total solvent is 10 to 60% by weight, a preferable ratio is 15 to 50% by weight, and a more preferable ratio is 20 to 45% by weight.

The poor solvent is used at a ratio of 10% by weight or more with respect to the total solvent weight in order to prevent the occurrence of liquid shrinkage due to printing defects and evaporation from the edge portion. On the contrary, in order to prevent the precipitation of the polymer in the solution due to the decrease in the proportion of the good solvent, the resulting clogging of the nozzles and heads of the inkjet device, and the occurrence of in-plane unevenness of the coating film. It is used at a ratio of 60% by weight or less based on the weight of the solvent.

The ratio of the third solvent to the total solvent weight is 0.1 to 20% by weight, a preferable ratio is 0.1 to 18% by weight, and a more preferable ratio is 0.1 to 15% by weight.

The third solvent is used at a ratio of 0.1% by weight or more with respect to the total solvent in order to prevent deterioration of the wettability of the solution and occurrence of in-plane unevenness in the scanning direction of the head. On the contrary, it is used in a ratio of 20% by weight or less with respect to the total solvent in order to prevent deterioration of edge linearity due to the solution being too wet and spread.

<Liquid crystal alignment agent>
The liquid crystal alignment agent of the present invention is a reaction product of at least one selected from tetracarboxylic dianhydride and its derivative and a diamine. The derivative of the tetracarboxylic dianhydride is a tetracarboxylic dianhydride or a tetracarboxylic dianhydride dichloride. A polyamic acid derivative is a component that dissolves in a solvent when it is used as a liquid crystal alignment agent containing a solvent, which will be described later. When the liquid crystal alignment agent is used as a liquid crystal alignment film, a liquid crystal alignment film containing polyimide as a main component. It is a component that can form. Examples of such a polyamic acid derivative include soluble polyimide, polyamic acid ester, polyamic acid amide, and the like. More specifically, 1) a polyimide in which all aminos and carboxyl of the polyamic acid undergo a dehydration ring closure reaction. 2) Partial polyimide partially dehydrated and ring-closed, 3) Polyamic acid ester in which the carboxyl of polyamic acid is converted to ester, 4) Part of acid dianhydride contained in tetracarboxylic acid dianhydride compound is organic dicarboxylic Examples thereof include a polyamic acid-polyimide copolymer obtained by substituting with an acid for reaction, and 5) polyamideimide obtained by dehydrating and ring-closing a part or all of the polyamic acid-polyimide copolymer. The polyamic acid and its derivative may be one kind of polymer or two or more kinds. Further, the polyamic acid and its derivative may be any polymer having a structure of a reaction product of tetracarboxylic dianhydride and diamine, and other raw materials may be used except for the reaction of tetracarboxylic dianhydride and diamine. It may contain reaction products from other reactions.

The polyamic acid ester can be synthesized by reacting the above-mentioned polyamic acid with a hydroxyl group-containing compound, a halide, an epoxy group-containing compound, or the like, or a tetracarboxylic dianester or tetracarboxylic derived from a tetracarboxylic dianhydride. It can be synthesized by a method of synthesizing by reacting an acid diester dichloride with a diamine. The tetracarboxylic dianester derived from the tetracarboxylic dianhydride can be obtained, for example, by reacting the tetracarboxylic dianhydride with 2 equivalents of an alcohol to open the ring, and the tetracarboxylic dianester dichloride is a tetracarboxylic acid. It can be obtained by reacting the diester with 2 equivalents of a chlorinating agent (eg, thionyl chloride, etc.). The polyamic acid ester may have only an amic acid ester structure, or may be a partial esterified product in which an amic acid structure and an amic acid ester structure coexist.

The tetracarboxylic dianhydride used for producing the polyamic acid and its derivative contained in the liquid crystal alignment agent of the present invention will be described. The tetracarboxylic dianhydride used in the present invention can be selected from known tetracarboxylic dianhydrides without limitation. Such tetracarboxylic acid dianhydrides include aromatic systems (including heteroaromatic ring systems) in which the dicarboxylic acid anhydride is directly bonded to the aromatic ring, and aliphatic groups in which the dicarboxylic acid anhydride is not directly bonded to the aromatic ring. It may belong to any group of systems (including heterocyclic systems). For the tetracarboxylic dianhydride, one compound may be reacted with a diamine, or two or more compounds may be mixed and reacted with a diamine. As used herein, the term "tetracarboxylic dianhydride" refers not only to one compound, but may also include a mixture of two or more compounds in its meaning.

The tetracarboxylic dianhydride can be roughly classified into a tetracarboxylic dianhydride having a photoreactive structure and a tetracarboxylic dianhydride having no photoreactive structure.

Preferable examples of the tetracarboxylic dianhydride having no photoreactive structure include the formulas (AN-I) to the viewpoints of easy availability of raw materials, ease of polymer polymerization, and electrical properties of the film. Examples thereof include tetracarboxylic dianhydride represented by (AN-VII).

式（Ｇ１３−１）において、Ｇ^１３ａおよびＧ^１３ｂは独立して、単結合、−Ｏ−または−ＮＨＣＯ−で表される２価の基である。 In formulas (AN-I), (AN-IV) and (AN-V), X is independently single-bonded or -CH _2- . In formula (AN-II), G is a single bond, alkylene with 1 to 20 carbon atoms, -CO-, -O-, -S-, -SO _2- , -C (CH ₃ ) _2- , -C ( CF ₃ ) _2- or a divalent group represented by the following formula (G13-1).

In formula (G13-1), G ^13a and G ^13b are independently single-bonded, divalent groups represented by -O- or -NHCO-.

In formulas (AN-II) to (AN-IV), Y is one independently selected from the group of trivalent groups below, and the bond is linked to any carbon of this group. At least one hydrogen may be replaced with methyl, ethyl or phenyl.

In formulas (AN-III) to (AN-V), ring A ¹⁰ is a group of a monocyclic hydrocarbon having 3 to 10 carbon atoms or a group of a fused polycyclic hydrocarbon having 6 to 30 carbon atoms. At least one hydrogen of the group may be replaced with methyl, ethyl or phenyl, the bond hanging on the ring is linked to any carbon that makes up the ring, and the two bonds are the same carbon. May be connected to. In the formula (AN-VI), X ¹⁰ is independently an alkylene having 2 to 6 carbon atoms, Me represents methyl, and Ph represents phenyl. In formula (AN-VII), G ¹⁰ is independently -O-, -COO- or -OCO- and r is independently 0 or 1.

More specifically, tetracarboxylic dianhydrides represented by the following formulas (AN-1) and (AN-3) to (AN-16-15) can be mentioned.

式（ＡＮ−１）において、Ｇ^１１は単結合、炭素数１〜１２のアルキレン、１，４−フェニレン、または１，４−シクロヘキシレンである。Ｘ^１１は独立して単結合または−ＣＨ_２−である。Ｇ^１２は独立して下記の３価の基のどちらかである。

Ｇ^１２が＞ＣＨ−であるとき、＞ＣＨ−の水素は−ＣＨ_３に置き換えられてもよい。Ｇ^１２が＞Ｎ−であるとき、Ｇ^１１が単結合および−ＣＨ_２−であることはなく、Ｘ^１１は単結合であることはない。そしてＲ^１１は独立して水素または−ＣＨ_３である。 [Tetracarboxylic dianhydride represented by the formula (AN-1)]

In formula (AN-1), G ¹¹ is a single bond, alkylene with 1-12 carbon atoms, 1,4-phenylene, or 1,4-cyclohexylene. X ¹¹ is independently single-bonded or -CH _2- . G ¹² is independently one of the following trivalent groups.

When G ¹² is> CH-, the hydrogen in> CH- may be replaced by _{-CH 3.} When G ¹² is> N-, G ¹¹ is not single-bonded and -CH _2- , and X ¹¹ is not single-bonded. And R ¹¹ is independently hydrogen or -CH ₃ .

式（ＡＮ−１−２）および（ＡＮ−１−１４）において、ｍは１〜１２の整数である。 Examples of the tetracarboxylic dianhydride represented by the formula (AN-1) include a compound represented by the following formula.

In equations (AN-1-2) and (AN-1-14), m is an integer of 1-12.

式（ＡＮ−３）において、環Ａ^１１はシクロヘキサン環またはベンゼン環である。 [Tetracarboxylic dianhydride represented by the formula (AN-3)]

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

Examples of the tetracarboxylic dianhydride represented by the formula (AN-3) include a compound represented by the following formula.

式（ＡＮ−４）において、Ｇ^１３は単結合、−（ＣＨ_２）_ｍ−、−Ｏ−、−Ｓ−、−Ｃ（ＣＨ_３）_２−、−ＳＯ_２−、−ＣＯ−、−Ｃ（ＣＦ_３）_２−、または下記の式（Ｇ１３−１）で表される２価の基であり、ｍは１〜１２の整数である。環Ａ^１１は独立してシクロヘキサン環またはベンゼン環である。Ｇ^１３は環Ａ^１１の任意の位置に結合してよい。

式（Ｇ１３−１）において、Ｇ^１３ａおよびＧ^１３ｂは独立して、単結合、−Ｏ−または−ＮＨＣＯ−で表される２価の基である。フェニレンは、１，４−フェニレンおよび１，３−フェニレンが好ましい。 [Tetracarboxylic dianhydride represented by the formula (AN-4)]

In formula (AN-4), G ¹³ is a single bond,-(CH ₂ ) _m- , -O-, -S-, -C (CH ₃ ) _2- , -SO _2- , -CO-, -C. (CF ₃ ) _2- or a divalent group represented by the following formula (G13-1), and m is an integer of 1 to 12. Ring A ¹¹ is independently a cyclohexane ring or a benzene ring. G ¹³ may be coupled to any position on ring A ^11.

In formula (G13-1), G ^13a and G ^13b are independently single-bonded, divalent groups represented by -O- or -NHCO-. Phenylene is preferably 1,4-phenylene and 1,3-phenylene.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-4) include a compound represented by the following formula.

式（ＡＮ−４−１７）において、ｍは１〜１２の整数である。

In equation (AN-4-17), m is an integer of 1-12.

式（ＡＮ−５）において、Ｒ^１１は独立して水素、または−ＣＨ_３である。ベンゼン環を構成する炭素原子に結合位置が固定されていないＲ^１１は、ベンゼン環における結合位置が任意であることを示す。 [Tetracarboxylic dianhydride represented by the formula (AN-5)]

In formula (AN-5), R ¹¹ is independently hydrogen, or −CH ₃ . ^{R 11} in which the bond position is not fixed to the carbon atom constituting the benzene ring indicates that the bond position in the benzene ring is arbitrary.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-5) include a compound represented by the following formula.

式（ＡＮ−６）において、Ｘ^１１は独立して単結合または−ＣＨ_２−である。Ｘ^１２は独立して−ＣＨ_２−、−ＣＨ_２ＣＨ_２−または−ＣＨ＝ＣＨ−である。ｎは１または２である。 [Tetracarboxylic dianhydride represented by the formula (AN-6)]

In formula (AN-6), X ¹¹ is independently single bond or −CH ₂₋ . X ¹² is independently −CH ₂ −, _{−CH 2} CH ₂ − or −CH = CH −. n is 1 or 2.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-6) include a compound represented by the following formula.

式（ＡＮ−７）において、Ｘ^１１は単結合または−ＣＨ_２−である。 [Tetracarboxylic dianhydride represented by the formula (AN-7)]

In formula (AN-7), X ¹¹ is a single bond or −CH ₂₋ .

Examples of the tetracarboxylic dianhydride represented by the formula (AN-7) include a compound represented by the following formula.

式（ＡＮ−８）において、Ｘ^１１は単結合または−ＣＨ_２−である。Ｒ^１２は水素、−ＣＨ_３、−ＣＨ_２ＣＨ_３、またはフェニルであり、環Ａ^１２はシクロヘキサン環またはシクロヘキセン環である。 [Tetracarboxylic dianhydride represented by the formula (AN-8)]

In equation (AN-8), X ¹¹ is a single bond or −CH ₂₋ . R ¹² is hydrogen, -CH ₃ , -CH ₂ CH ₃ , or phenyl, and ring A ¹² is a cyclohexane ring or a cyclohexene ring.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-8) include a compound represented by the following formula.

式（ＡＮ−９）において、ｒは独立して０または１である。 [Tetracarboxylic dianhydride represented by the formula (AN-9)]

In equation (AN-9), r is independently 0 or 1.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-9) include a compound represented by the following formula.

[Tetracarboxylic dianhydride represented by the formulas (AN-10-1) and (AN-10-2)]

式（ＡＮ−１１）において、環Ａ^１１は独立してシクロヘキサン環またはベンゼン環である。 [Tetracarboxylic dianhydride represented by the formula (AN-11)]

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

Examples of the tetracarboxylic dianhydride represented by the formula (AN-11) include a compound represented by the following formula.

式（ＡＮ−１２）において、環Ａ^１１は独立してシクロヘキサン環またはベンゼン環である。 [Tetracarboxylic dianhydride represented by the formula (AN-12)]

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

Examples of the tetracarboxylic dianhydride represented by the formula (AN-12) include compounds represented by the following formula.

式（ＡＮ−１３）において、Ｘ^１３は独立して炭素数２〜６のアルキレンであり、Ｐｈはフェニルを表す。 [Tetracarboxylic dianhydride represented by the formula (AN-13)]

In the formula (AN-13), X ¹³ is independently an alkylene having 2 to 6 carbon atoms, and Ph represents phenyl.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-13) include a compound represented by the following formula.

式（ＡＮ−１４）において、Ｇ^１４は独立して−Ｏ−、−ＣＯＯ−または−ＯＣＯ−であり、ｒは独立して０または１である。 [Tetracarboxylic dianhydride represented by the formula (AN-14)]

In formula (AN-14), G ¹⁴ is independently -O-, -COO- or -OCO-, and r is independently 0 or 1.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-14) include compounds represented by the following formula.

式（ＡＮ−１５）において、ｗは１〜１０の整数である。 [Tetracarboxylic dianhydride represented by the formula (AN-15)]

In equation (AN-15), w is an integer of 1-10.

Examples of the tetracarboxylic dianhydride represented by the formula (AN-15) include a compound represented by the following formula.

Examples of the tetracarboxylic dianhydride other than the above include the following compounds.

A suitable material for improving each property of the tetracarboxylic dianhydride having no photoreactive structure will be described.

When it is important to improve the orientation of the liquid crystal, the compounds represented by the formulas (AN-1), (AN-3), and (AN-4) are preferable, and the compound represented by the formula (AN-1-2) is preferable. , (AN-1-13), (AN-3-2), (AN-4-5), (AN-4-17) and (AN-4-29) are particularly preferable, among others. In the formula (AN-1-2), m = 4 or 8 is preferable, in the formula (AN-4-17), m = 4 or 8 is preferable, and m = 8 is particularly preferable.

When it is important to improve the transmittance of the liquid crystal display element, among the above-mentioned tetracarboxylic dianhydrides, the formulas (AN-1-1), (AN-1-2), and (AN-3-3) are used. 1), (AN-4-17), (AN-4-30), (AN-5-1), (AN-7-2), (AN-10-1), (AN-16-3) , And the compound represented by (AN-16-4) are preferable, among them, m = 4 or 8 is preferable in the formula (AN-1-2), and m = in the formula (AN-4-17). 4 or 8 is preferable, and m = 8 is particularly preferable.

When it is important to improve the VHR of the liquid crystal display element, among the above-mentioned tetracarboxylic dianhydrides, the formulas (AN-1-1), (AN-1-2), (AN-3-1) ), (AN-4-17), (AN-4-30), (AN-7-2), (AN-10-1), (AN-16-1), (AN-16-3), And the compound represented by (AN-16-4) is preferable, among them, m = 4 or 8 is preferable in the formula (AN-1-2), and m = 4 in the formula (AN-4-17). , Or 8, and m = 8 is particularly preferable.

Improving the relaxation rate of the residual charge (residual DC) in the alignment film by reducing the volume resistance value of the liquid crystal alignment film is effective as one of the methods for preventing seizure. When this purpose is emphasized, among the above-mentioned tetracarboxylic dianhydrides, the formulas (AN-1-13), (AN-3-2), (AN-4-21), and (AN-4-21) are used. The compounds represented by 29) and (AN-11-3) are preferable.

The diamine and dihydrazide used for producing the polyamic acid and its derivative contained in the liquid crystal alignment agent of the present invention will be described. The diamine and dihydrazide used in the present invention can be selected from known diamines and dihydrazides without limitation. For the diamine, one compound may be reacted with a tetracarboxylic dianhydride, or two or more compounds may be mixed and reacted with a tetracarboxylic dianhydride. As used herein, the term "diamine" not only refers to one compound, but may also include a mixture of two or more compounds in its meaning. In addition, in this specification, dihydrazide is also treated as "diamine".

Like the tetracarboxylic dianhydride, the diamine compound can be roughly classified into a diamine compound having a photoreactive structure and a diamine compound having no photoreactive structure. Diamines that do not have a photoreactive structure can be divided into two types according to their structure. That is, when the skeleton connecting two amino groups is viewed as a main chain, it is a group branched from the main chain, that is, a diamine having a side chain group and a diamine having no side chain group. This side chain group is a group having an effect of increasing the pretilt angle. The side chain group having such an effect needs to be a group having 3 or more carbon atoms, and specific examples thereof include alkyl having 3 or more carbon atoms, alkoxy having 3 or more carbon atoms, alkoxyalkyl having 3 or more carbon atoms, and Groups having a steroid skeleton can be mentioned. A group having one or more rings, the terminal ring having any one of an alkyl having 1 or more carbon atoms, an alkoxy having 1 or more carbon atoms, and an alkoxyalkyl having 2 or more carbon atoms as a substituent. It has an effect as a side chain group. In the following description, a diamine having such a side chain group may be referred to as a side chain type diamine. A diamine that does not have such a side chain group may be referred to as a non-side chain diamine.

By properly using the non-side chain diamine and the side chain diamine properly, it is possible to correspond to the pretilt angle required for each. The side chain diamine is preferably used in combination to the extent that the characteristics of the present invention are not impaired. Further, it is preferable to select and use the side chain type diamine and the non-side chain type diamine for the purpose of improving the vertical orientation with respect to the liquid crystal, the voltage retention rate, the seizure characteristics and the orientation.

The non-side chain diamine will be described. Examples of the diamine having no known side chain include diamines of the following formulas (DI-1) to (DI-16).

In the above equation (DI-1), G ²⁰ is −CH ₂ −, at least one −CH ₂ − may be replaced by −NH−, −O−, and m is an integer of 1-12. And at least one hydrogen of the alkylene may be replaced with −OH. In formulas (DI-3) and formulas (DI-5) to formulas (DI-7), G ²¹ is independently single-bonded, -NH-, -NCH _3- , -O-, -S-, -S. -S-, -SO _2- , -CO-, -COO-, -CONCH _3- , -CONH-, -C (CH ₃ ) _2- , -C (CF ₃ ) ₂ -,-(CH ₂ ) _m -, -O- (CH ₂ ) _m- O-, -N (CH ₃ )-(CH ₂ ) _k- N (CH ₃ )-,-( _{OC 2} H ₄ ) _m- O-, -O _{-CH 2 -C (CF 3) 2} -CH 2 -O -, - O-CO- (CH 2) m -CO-O -, - CO-O- (CH 2) m -O-CO -, - _{(CH 2) m -NH- (CH} 2) m -, - CO- (CH 2) k -NH- (CH 2) k -, - (NH- (CH 2) m) k -NH -, - CO -C ₃ H _6- (NH-C ₃ H ₆ ) _n- CO-, or -S- (CH ₂ ) _m -S-, m is an integer of 1 to 12 independently, and k is independent. It is an integer of 1 to 5, and n is 1 or 2. In equation (DI-4), s is an independently integer of 0-2. In formulas (DI-6) and (DI-7), G ²² is independently single-bonded, -O-, -S-, -CO-, -C (CH ₃ ) _2- , -C (CF _3). ) _2- , -NH-, or an alkylene having 1 to 10 carbon atoms. At least one hydrogen of the cyclohexane ring and the benzene ring in the formulas (DI-2) to (DI-7) is -F, -Cl, an alkyl having 1 to 3 carbon atoms, -OCH ₃ , -OH, -CF. ₃ , -CO ₂ H, -CONH ₂ , -NHC ₆ H ₅ , may be replaced with phenyl, or benzyl, and in addition, in formula (DI-4), at least one hydrogen in the benzene ring is in the formula (DI-4) below. It may be replaced with one selected from the group of groups represented by the formulas (DI-4-a) to (DI-4-e). A group whose bond position is not fixed to the carbon atom constituting the ring indicates that the bond position in the ring is arbitrary. The bond position _{of -NH 2} to the cyclohexane ring or the benzene ring is any position except the bond position of ^{G 21} or G ^22.

式（ＤＩ−４−ａ）および式（ＤＩ−４−ｂ）において、Ｒ^２０は独立して水素または−ＣＨ_３である。

In formulas (DI-4-a) and (DI-4-b), R ²⁰ is independently hydrogen or −CH ₃ .

式（ＤＩ−１１）において、ｒは０または１である。式（ＤＩ−８）〜式（ＤＩ−１１）において、環に結合する−ＮＨ_２の結合位置は、任意の位置である。

In formula (DI-11), r is 0 or 1. In the formulas (DI-8) to (DI-11), _{the binding position of −NH 2} to be bonded to the ring is an arbitrary position.

In formula (DI-12), R ²¹ and R ²² are independently alkyl or phenyl with 1-3 carbon atoms, and G ²³ is independently alkylene, phenylene or alkyl-substituted phenylene with 1 to 6 carbon atoms. And w is an integer of 1-10. In formula (DI-13), R ²³ is independently an alkyl having 1 to 5 carbon atoms, alkoxy or −Cl having 1 to 5 carbon atoms, p is independently an integer of 0 to 3, and q is an integer of 0 to 3 independently. It is an integer from 0 to 4. In formula (DI-14), ring B is a monocyclic complex aromatic, R ²⁴ is hydrogen, −F, −Cl, alkyl, alkoxy, vinyl, alkynyl having 1 to 6 carbon atoms, and q is independent. Then, it is an integer of 0 to 4. In formula (DI-15), ring C is a monocycle containing a heteroatom. In formula (DI-16), G ²⁴ is a single bond, alkylene or 1,4-phenylene having 2 to 6 carbon atoms, and r is 0 or 1. A group whose bond position is not fixed to the carbon atom constituting the ring indicates that the bond position in the ring is arbitrary. In the formulas (DI-13) to (DI-16), _{the binding position of -NH 2} to be bonded to the ring is an arbitrary position.

Specific examples of the following formulas (DI-1-1) to (DI-16-1) can be given as diamines having no side chain of the above formulas (DI-1) to (DI-16). it can.

式（ＤＩ−１−７）および式（ＤＩ−１−８）において、ｋは独立して、１〜３の整数である。 An example of the diamine represented by the formula (DI-1) is shown below.

In equations (DI-1-7) and (DI-1-8), k is independently an integer of 1-3.

Examples of diamines represented by the formulas (DI-2) and (DI-3) are shown below.

An example of the diamine represented by the formula (DI-4) is shown below.

式（ＤＩ−５−１）において、ｍは１〜１２の整数である。 An example of the diamine represented by the formula (DI-5) is shown below.

In equation (DI-5-1), m is an integer of 1-12.

式（ＤＩ−５−１）、式（ＤＩ−５−１２）および式（ＤＩ−５−１３）において、ｍは１〜１２の整数である。

In formula (DI-5-1), formula (DI-5-12) and formula (DI-5-13), m is an integer of 1-12.

式（ＤＩ−５−１６）において、ｖは１〜６の整数である。

In equation (DI-5-16), v is an integer of 1-6.

式（ＤＩ−５−３０）において、ｋは１〜５の整数である。

In formula (DI-5-30), k is an integer of 1-5.

式（ＤＩ−５−３５）〜式（ＤＩ−５−３７）、および式（ＤＩ−５−３９）において、ｍは独立して１〜１２の整数であり、式（ＤＩ−５−３８）および式（ＤＩ−５−３９）において、ｋは独立して１〜５の整数であり、式（ＤＩ−５−４０）において、ｎは１または２の整数である。

In formulas (DI-5-35) to (DI-5-37), and formula (DI-5-39), m is independently an integer of 1-12, and formula (DI-5-38). And in equation (DI-5-39), k is independently an integer of 1-5, and in equation (DI-5-40), n is an integer of 1 or 2.

An example of the diamine represented by the formula (DI-6) is shown below.

式（ＤＩ−７−３）および式（ＤＩ−７−４）において、ｍは独立して１〜１２の整数であり、ｎは独立して１または２である。 An example of the diamine represented by the formula (DI-7) is shown below.

In equations (DI-7-3) and (DI-7-4), m is independently an integer of 1-12 and n is independently 1 or 2.

式（ＤＩ−７−１２）において、ｍは１〜１２の整数である。

In equation (DI-7-12), m is an integer of 1-12.

An example of the diamine represented by the formula (DI-8) is shown below.

An example of the diamine represented by the formula (DI-9) is shown below.

An example of the diamine represented by the formula (DI-10) is shown below.

An example of the diamine represented by the formula (DI-11) is shown below.

An example of the diamine represented by the formula (DI-12) is shown below.

An example of the diamine represented by the formula (DI-13) is shown below.

An example of the diamine represented by the formula (DI-14) is shown below.

An example of the diamine represented by the formula (DI-15) is shown below.

An example of the diamine represented by the formula (DI-16) is shown below.

The dihydrazide will be described. Examples of dihydrazide having no known side chain include the following formulas (DIH-1) to (DIH-3).

In formula (DIH-1), G ²⁵ is a single bond, alkylene with 1 to 20 carbon atoms, -CO-, -O-, -S-, -SO _2- , -C (CH ₃ ) _2- , or-. C (CF ₃ ) _2- . In formula (DIH-2), ring D is a cyclohexane ring, a benzene ring or a naphthalene ring, and at least one hydrogen of this ring may be replaced with methyl, ethyl, or phenyl. In formula (DIH-3), ring E is independently a cyclohexane ring or a benzene ring, at least one hydrogen of this ring may be replaced with methyl, ethyl, or phenyl, where Y is a single bond, carbon. The numbers 1 to 20 are alkylene, -CO-, -O-, -S-, -SO _2- , -C (CH ₃ ) _2- , or -C (CF ₃ ) _2- . In the formula (DIH-2) and the formula (DIH-3), _{the binding position of −CONHNH 2} bonded to the ring is an arbitrary position.

式（ＤＩＨ−１−２）において、ｍは１〜１２の整数である。 Examples of formulas (DIH-1) to (DIH-3) are shown below.

In the formula (DIH-1-2), m is an integer of 1-12.

Such non-side chain diamines and dihydrazides have an effect of improving electrical characteristics such as lowering the ion density of the liquid crystal display element. When non-side chain diamine and / or dihydrazide is used as the diamine used for producing the liquid crystal alignment agent composed of polyamic acid, polyamic acid ester or polyimide used for the liquid crystal alignment agent of the present invention, the total amount of diamine and dihydrazide The proportion thereof is preferably 0 to 90 mol%, more preferably 0 to 50 mol%.

The side chain diamine will be described. Examples of the side chain group of the side chain diamine include the following groups.

As side chain groups, first, alkyl, alkyloxy, alkyloxyalkyl, alkylcarbonyl, alkylcarbonyloxy, alkyloxycarbonyl, alkylaminocarbonyl, alkenyl, alkenyloxy, alkenylcarbonyl, alkenylcarbonyloxy, alkenyloxycarbonyl, alkenylaminocarbonyl, Examples thereof include alkynyl, alkynyloxy, alkynylcarbonyl, alkynylcarbonyloxy, alkynyloxycarbonyl, alkynylaminocarbonyl and the like. Alkyl, alkenyl and alkynyl in these groups are all groups having 3 or more carbon atoms. However, in alkyloxyalkyl, the total number of carbon atoms in the entire group may be 3 or more. These groups may be linear or branched.

Next, phenyl, phenylalkyl, phenylalkyloxy, phenyloxy, provided that the terminal ring has an alkyl having 1 or more carbon atoms, an alkoxy having 1 or more carbon atoms, or an alkoxyalkyl having 2 or more carbon atoms as a substituent. Phenylcarbonyl, phenylcarbonyloxy, phenyloxycarbonyl, phenylaminocarbonyl, phenylcyclohexyloxy, cycloalkyl with 3 or more carbon atoms, cyclohexylalkyl, cyclohexyloxy, cyclohexyloxycarbonyl, cyclohexylphenyl, cyclohexylphenylalkyl, cyclohexylphenyloxy, bis ( Ring structure of cyclohexyl) oxy, bis (cyclohexyl) alkyl, bis (cyclohexyl) phenyl, bis (cyclohexyl) phenylalkyl, bis (cyclohexyl) oxycarbonyl, bis (cyclohexyl) phenyloxycarbonyl, and cyclohexylbis (phenyl) oxycarbonyl Can be mentioned.

Further, a group having two or more benzene rings, a group having two or more cyclohexane rings, or a group having two or more rings composed of a benzene ring and a cyclohexane ring, in which the bonding groups are independently single-bonded. -O-, -COO-, -OCO-, -CONH- or an alkylene having 1 to 3 carbon atoms, and the terminal ring is an alkyl having 1 or more carbon atoms as a substituent, a fluorine-substituted alkyl having 1 or more carbon atoms, and carbon. Examples thereof include a ring aggregate group having an alkoxy having a number of 1 or more, or an alkoxyalkyl having a carbon number of 2 or more. A group having a steroid skeleton is also effective as a side chain group.

式（ＤＩ−３１）において、Ｇ^２６は単結合、−Ｏ−、−ＣＯＯ−、−ＯＣＯ−、−ＣＯ−、−ＣＯＮＨ−、−ＣＨ_２Ｏ−、−ＯＣＨ_２−、−ＣＦ_２Ｏ−、−ＯＣＦ_２−、または−（ＣＨ_２）_ｍ’−であり、ｍ’は１〜１２の整数である。Ｇ^２６の好ましい例は単結合、−Ｏ−、−ＣＯＯ−、−ＯＣＯ−、−ＣＨ_２Ｏ−、および炭素数１〜３のアルキレンであり、特に好ましい例は単結合、−Ｏ−、−ＣＯＯ−、−ＯＣＯ−、−ＣＨ_２Ｏ−、−ＣＨ_２−および−ＣＨ_２ＣＨ_２−である。Ｒ^２５は炭素数３〜３０のアルキル、フェニル、ステロイド骨格を有する基、または下記の式（ＤＩ−３１−ａ）で表される基である。このアルキルにおいて、少なくとも１つの水素は−Ｆで置き換えられてもよく、そして少なくとも１つの−ＣＨ_２−は−Ｏ−、−ＣＨ＝ＣＨ−または−Ｃ≡Ｃ−で置き換えられていてもよい。このフェニルの水素は、−Ｆ、−ＣＨ_３、−ＯＣＨ_３、−ＯＣＨ_２Ｆ、−ＯＣＨＦ_２、−ＯＣＦ_３、炭素数３〜３０のアルキルまたは炭素数３〜３０のアルコキシで置き換えられていてもよい。ベンゼン環に結合する−ＮＨ_２の結合位置はその環において任意の位置であることを示すが、その結合位置はメタまたはパラであることが好ましい。即ち、基「Ｒ^２５−Ｇ^２６−」の結合位置を１位としたとき、２つの結合位置は３位と５位、または２位と５位であることが好ましい。 Examples of the diamine having a side chain include compounds represented by the following formulas (DI-31) to (DI-35).

In formula (DI-31), G ²⁶ is a single bond, -O-, -COO-, -OCO-, -CO-, -CONH-, -CH ₂ O-, -OCH _2- , -CF ₂ O- , -OCF ₂ -, or - _(CH 2) _{m '-} it is and, m' is an integer from 1 to 12. Preferred examples of G ²⁶ are single bonds, -O-, -COO-, -OCO-, -CH ₂ O-, and alkylene with 1-3 carbon atoms, with particularly preferred examples being single bonds, -O-,-. _{COO -, - OCO -, -} CH 2 O -, - CH 2 - and _-CH 2 CH ₂ -. R ²⁵ is a group having an alkyl, phenyl, or steroid skeleton having 3 to 30 carbon atoms, or a group represented by the following formula (DI-31-a). In this alkyl, at least one hydrogen may be replaced by −F, and at least one −CH ₂ − may be replaced by −O−, −CH = CH− or −C≡C−. The hydrogen of this phenyl is _{replaced by -F, -CH 3} , -OCH ₃ , -OCH ₂ F, -OCHF ₂ , -OCF ₃ , alkyl with 3 to 30 carbon atoms or alkoxy with 3 to 30 carbon atoms. May be good. _{The bond position of -NH 2} bonded to the benzene ring indicates that it is an arbitrary position in the ring, but the bond position is preferably meta or para. That is, the group "R ^{25 -G} 26 ^-" when the binding position of the 1-position, of the two coupling positions 3 and 5 positions, or preferably 2-position and 5-position.

式（ＤＩ−３１−ａ）において、Ｇ^２７、Ｇ^２８およびＧ^２９は結合基であり、これらは独立して単結合、または炭素数１〜１２のアルキレンであり、このアルキレンの１以上の−ＣＨ_２−は−Ｏ−、−ＣＯＯ−、−ＯＣＯ−、−ＣＯＮＨ−、−ＣＨ＝ＣＨ−で置き換えられていてもよい。環Ｂ^２１、環Ｂ^２２、環Ｂ^２３および環Ｂ^２４は独立して１，４−フェニレン、１，４−シクロへキシレン、１，３−ジオキサン−２，５−ジイル、ピリミジン−２，５−ジイル、ピリジン−２，５−ジイル、ピペリジン−１，４−ジイル、ナフタレン−１，５−ジイル、ナフタレン−２，７−ジイルまたはアントラセン−９，１０−ジイルであり、環Ｂ^２１、環Ｂ^２２、環Ｂ^２３および環Ｂ^２４において、少なくとも１つの水素は−Ｆまたは−ＣＨ_３で置き換えられてもよく、ｓ、ｔおよびｕは独立して０〜２の整数であって、これらの合計は０〜５であり、ｓ、ｔまたはｕが２であるとき、各々の括弧内の２つの結合基は同じであっても異なってもよく、そして、２つの環は同じであっても異なっていてもよい。Ｒ^２６は水素、−Ｆ、−ＯＨ、炭素数１〜３０のアルキル、炭素数１〜３０のフッ素置換アルキル、炭素数１〜３０のアルコキシ、−ＣＮ、−ＯＣＨ_２Ｆ、−ＯＣＨＦ_２、または−ＯＣＦ_３であり、この炭素数１〜３０のアルキルの少なくとも１つの−ＣＨ_２−は下記式（ＤＩ−３１−ｂ）で表される２価の基で置き換えられていてもよい。

In formula (DI-31-a), G ²⁷ , G ²⁸ and G ²⁹ are linking groups, which are independently single bonds or alkylenes having 1 to 12 carbon atoms and are one or more-one or more of the alkylenes. CH ₂ − may be replaced by −O−, −COO−, −OCO−, −CONH−, −CH = CH−. Ring B ²¹ , Ring B ²² , Ring B ²³ and Ring B ²⁴ are independently 1,4-phenylene, 1,4-cyclohexylene, 1,3-dioxane-2,5-diyl, pyrimidine-2,5. -Diyl, pyridine-2,5-diyl, piperidine-1,4-diyl, naphthalene-1,5-diyl, naphthalene-2,7-diyl or anthracene-9,10-diyl, ring B ²¹ , ring In B ²² , ring B ²³ and ring B ²⁴ , at least one hydrogen may _{be replaced by -F or -CH 3} , where s, t and u are independently integers 0-2. The sum is 0-5, and when s, t or u is 2, the two binding groups in each parenthesis may be the same or different, and the two rings may be the same. It may be different. R ²⁶ is hydrogen, -F, -OH, alkyl of 1 to 30 carbon atoms, a fluorine-substituted alkyl having 1 to 30 carbon atoms, C1-30 _{alkoxy, -CN, -OCH 2 F, -OCHF} 2 or, It is −OCF _{3 , and at least one −CH 2} − of the alkyl having 1 to 30 carbon atoms may be replaced with a divalent group represented by the following formula (DI-31-b).

式（ＤＩ−３１−ｂ）において、Ｒ^２７およびＲ^２８は独立して炭素数１〜３のアルキルであり、ｖは１〜６の整数である。Ｒ^２６の好ましい例は炭素数１〜３０のアルキルおよび炭素数１〜３０のアルコキシである。

In the formula (DI-31-b), R ²⁷ and R ²⁸ are independently alkyl having 1 to 3 carbon atoms, and v is an integer of 1 to 6. Preferred examples of R ²⁶ are alkyl having 1 to 30 carbon atoms and alkoxy having 1 to 30 carbon atoms.

In formulas (DI-32) and (DI-33), G ³⁰ is independently single-bonded, -CO- or -CH _2- , and R ²⁹ is independently hydrogen or -CH ₃ , R. ^{Reference numeral 30} is hydrogen, an alkyl having 1 to 20 carbon atoms, or an alkenyl having 2 to 20 carbon atoms. At least one hydrogen in the benzene ring in formula (DI-32) and formula (DI-33) may be replaced with an alkyl or phenyl having 1 to 20 carbon atoms. Then, a group whose bond position is not fixed to any of the carbon atoms constituting the ring indicates that the bond position in the ring is arbitrary. It is preferable that one of the two groups "-phenylene-G ^30- O-" in the formula (DI-32) is bound to the 3-position of the steroid nucleus and the other is bound to the 6-position of the steroid nucleus. The binding positions of the two groups "-phenylene-G ^30- O-" in the formula (DI-33) to the benzene ring are preferably meta-positions or para-positions, respectively, with respect to the binding position of the steroid nucleus. In formulas (DI-32) and (DI-33), -NH ₂ bonded to the benzene ring indicates that the bonding position in the ring is arbitrary.

In formulas (DI-34) and (DI-35), G ³¹ is independently -O-, -NH- or an alkylene having 1 to 6 carbon atoms, and G ³² is a single bond or 1 to 3 carbon atoms. It is an alkylene of. R ³¹ is hydrogen or an alkyl having 1 to 20 carbon atoms, and at least one −CH ₂ − of this alkyl may be replaced by −O−, −CH = CH− or −C≡C−. R ³² is an alkyl having 6 to 22 carbon atoms, and R ³³ is hydrogen or an alkyl having 1 to 22 carbon atoms. Ring B ²⁵ is 1,4-phenylene or 1,4-cyclohexylene and r is 0 or 1. _{Then, -NH 2} bonded to the benzene ring indicates that the bonding position in the ring is arbitrary, but it is preferably in the meta position or the para position ^{independently with respect to the bonding position of G 31.}

Specific examples of side chain diamines are shown below. Examples of the diamine having a side chain of the above formulas (DI-31) to (DI-35) include compounds represented by the following formulas (DI-31-1) to (DI-35-3). it can.

Examples of the compound represented by the formula (DI-31) are shown below.

In formulas (DI-31-1) to (DI-31-11), R ³⁴ is an alkyl having 1 to 30 carbon atoms or an alkoxy having 1 to 30 carbon atoms, preferably an alkyl having 5 to 25 carbon atoms or It is an alkoxy having 5 to 25 carbon atoms. R ³⁵ is an alkyl having 1 to 30 carbon atoms or an alkoxy having 1 to 30 carbon atoms, preferably an alkyl having 3 to 25 carbon atoms or an alkoxy having 3 to 25 carbon atoms.

式（ＤＩ−３１−１２）〜式（ＤＩ−３１−１７）において、Ｒ^３６は炭素数４〜３０のアルキルであり、好ましくは炭素数６〜２５のアルキルである。Ｒ^３７は炭素数６〜３０のアルキルであり、好ましくは炭素数８〜２５のアルキルである。

In formulas (DI-31-12) to (DI-31-17), R ³⁶ is an alkyl having 4 to 30 carbon atoms, preferably an alkyl having 6 to 25 carbon atoms. R ³⁷ is an alkyl having 6 to 30 carbon atoms, preferably an alkyl having 8 to 25 carbon atoms.

式（ＤＩ−３１−１８）〜式（ＤＩ−３１−４３）において、Ｒ^３８は炭素数１〜２０のアルキルまたは炭素数１〜２０のアルコキシであり、好ましくは炭素数３〜２０のアルキルまたは炭素数３〜２０のアルコキシである。Ｒ^３９は水素、−Ｆ、炭素数１〜３０のアルキル、炭素数１〜３０のアルコキシ、−ＣＮ、−ＯＣＨ_２Ｆ、−ＯＣＨＦ_２または−ＯＣＦ_３であり、好ましくは炭素数３〜２５のアルキル、または炭素数３〜２５のアルコキシである。そしてＧ^３３は炭素数１〜２０のアルキレンである。

In formulas (DI-31-18) to (DI-31-43), R ³⁸ is an alkyl having 1 to 20 carbon atoms or an alkoxy having 1 to 20 carbon atoms, preferably an alkyl having 3 to 20 carbon atoms or It is an alkoxy having 3 to 20 carbon atoms. R ³⁹ is hydrogen, -F, alkyl having 1 to 30 carbon atoms, alkoxy having 1 to 30 carbon atoms, -CN, -OCH ₂ F, -OCHF ₂ or -OCF ₃ , preferably having 3 to 25 carbon atoms. It is an alkyl or an alkoxy having 3 to 25 carbon atoms. And G ³³ is an alkylene having 1 to 20 carbon atoms.

Examples of the compound represented by the formula (DI-32) are shown below.

Examples of the compound represented by the formula (DI-33) are shown below.

Examples of the compound represented by the formula (DI-34) are shown below.

式（ＤＩ−３４−１）〜式（ＤＩ−３４−１４）において、Ｒ^４０は水素または炭素数１〜２０のアルキル、好ましくは水素または炭素数１〜１０のアルキルであり、そしてＲ^４１は水素または炭素数１〜１２のアルキルである。

In formulas (DI-34-1) to (DI-34-14), R ⁴⁰ is hydrogen or an alkyl having 1 to 20 carbon atoms, preferably hydrogen or an alkyl having 1 to 10 carbon atoms, and R ⁴¹ is It is hydrogen or an alkyl having 1 to 12 carbon atoms.

式（ＤＩ−３５−１）〜式（ＤＩ−３５−３）において、Ｒ^３７は炭素数６〜３０のアルキルであり、Ｒ^４１は水素または炭素数１〜１２のアルキルである。 Examples of the compound represented by the formula (DI-35) are shown below.

In formulas (DI-35-1) to (DI-35-3), R ³⁷ is an alkyl having 6 to 30 carbon atoms, and R ⁴¹ is hydrogen or an alkyl having 1 to 12 carbon atoms.

式（ＤＩ−３６−１）〜式（ＤＩ−３６−８）において、Ｒ^４２は独立して炭素数３〜３０のアルキル基を表す。 The diamines in the present invention include formulas (DI-1-1) to formulas (DI-16-1), formulas (DIH-1-1) to formulas (DIH-3-6), and formulas (DI-31-1). ) ~ A diamine other than the diamine represented by the formula (DI-35-3) can also be used. Examples of such diamines include compounds represented by the following formulas (DI-36-1) to (DI-36-13).

In formulas (DI-36-1) to (DI-36-8), R ⁴² independently represents an alkyl group having 3 to 30 carbon atoms.

式（ＤＩ−３６−９）〜式（ＤＩ−３６−１１）において、ｅは独立して２〜１０の整数であり、式（ＤＩ−３６−１２）中、Ｒ^４３は独立して水素、−ＮＨＢｏｃまたは−Ｎ（Ｂｏｃ）_２であり、Ｒ^４３の少なくとも１つは−ＮＨＢｏｃまたは−Ｎ（Ｂｏｃ）_２であり、式（ＤＩ−３６−１３）において、Ｒ^４４は−ＮＨＢｏｃまたは−Ｎ（Ｂｏｃ）_２であり、ｍは１〜１２の整数であり、そして、式（ＤＩ−３６−１４）において、ｋは１〜５の整数である。ここで、Ｂｏｃはｔ−ブトキシカルボニル基である。

In equations (DI-36-9) to (DI-36-11), e is an independent integer of 2 to 10, and in equation (DI-36-12), R ⁴³ is independently hydrogen. -NHBoc or -N (Boc) ₂ , ^{at least one of R 43} is -NHBoc or -N (Boc) ₂ , and in formula (DI-36-13), R ⁴⁴ is -NHBoc or -N ( Boc) ₂ , m is an integer of 1-12, and in equation (DI-36-14), k is an integer of 1-5. Here, Boc is a t-butoxycarbonyl group.

In the above diamine and dihydrazide, suitable materials for improving each property will be described.

When it is important to further improve the orientation of the liquid crystal, among the above diamines and dihydrazides, the formula (DI-1-3), the formula (DI-4-1), and the formula (DI-5-1) , Equation (DI-5-5), Equation (DI-5-9), Equation (DI-5-12), Equation (DI-5-13), Equation (DI-5-29), Equation (DI- It is preferable to use the compounds represented by 6-7), the formula (DI-7-3), and the formula (DI-11-2). The diamine represented by the formula (DI-4-1), the formula (DI-5-1), the formula (DI-5-12), the formula (DI-5-13), and the formula (DI-7-3) More preferred. In the formula (DI-5-1), m = 2, 4 or 6 is preferable, and m = 4 is more preferable. In the formula (DI-5-12), m = 2 to 6 is preferable, and m = 5 is more preferable. In the formula (DI-5-13), m = 1 or 2 is preferable, and m = 1 is more preferable. In the formula (DI-7-3), m = 2, or 3, n = 1, or 2 is preferable, and m = 1 is more preferable.

When it is important to improve the transmittance, among the above diamines and dihydrazides, the formula (DI-1-3), the formula (DI-2-1), the formula (DI-5-1), and the formula ( It is preferable to use the compounds represented by DI-5-5), formula (DI-5-17), and formula (DI-7-3), and the diamine represented by (DI-2-1) is more preferable. preferable. In the formula (DI-5-1), m = 2, 4 or 6 is preferable, and m = 4 is more preferable. In the formula (DI-7-3), m = 2, or 3, n = 1, or 2 is preferable, and m = 1 is more preferable.

When it is important to improve the VHR of the liquid crystal display element, among the above diamines and dihydrazides, the formula (DI-2-1), the formula (DI-4-1), and the formula (DI-4-2) , Equation (DI-4-10), Equation (DI-4-15), Equation (DI-5-1), Equation (DI-5-28), Equation (DI-5-30), Equation (DI- It is preferable to use the compounds represented by the formulas (13-1), (DI-31-56), and (DI-36-14), and the formulas (DI-2-1) and (DI-5-1). ), Formula (DI-13-1), Formula (DI-31-56), and Formula (DI-36-14) are more preferred. In the formula (DI-5-1), m = 1 is preferable. In the formula (DI-5-30), k = 2 is preferable. In the formula (DI-36-14), k = 3 is preferable.

Improving the relaxation rate of the residual charge (residual DC) in the alignment film by reducing the volume resistance value of the liquid crystal alignment film is effective as one of the methods for preventing seizure. When this purpose is emphasized, among the above diamines and dihydrazides, the formula (DI-4-1), the formula (DI-4-2), the formula (DI-4-10), and the formula (DI-4-10) 15), Eq. (DI-5-1), Eq. (DI-5-12), Eq. (DI-5-13), Eq. (DI-5-28), and Eq. (DI-16-1). It is preferable to use the compound represented by the above, and the compound represented by the formula (DI-4-1), the formula (DI-5-1), and the formula (DI-5-13) is more preferable. In the formula (DI-5-1), m = 2, 4 or 6 is preferable, and m = 4 is more preferable. In the formula (DI-5-12), m = 2 to 6 is preferable, and m = 5 is more preferable. In the formula (DI-5-13), m = 1 or 2 is preferable, and m = 1 is more preferable.

In each diamine, a part of the diamine may be replaced with the monoamine in the range where the ratio of the monoamine to the diamine is 40 mol% or less. Such replacement can cause termination of the polymerization reaction when producing a polyamic acid, and can suppress further progress of the polymerization reaction. Therefore, by such replacement, the molecular weight of the obtained polymer (polyamic acid, polyamic acid ester or polyimide) can be easily controlled, and for example, the coating characteristics of the liquid crystal aligning agent can be improved without impairing the effect of the present invention. Can be improved. The diamine to be replaced with the monoamine may be one kind or two or more kinds as long as the effect of the present invention is not impaired. Examples of the monoamine include aniline, 4-hydroxyaniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine, n-nonylamine, n-decylamine and n-. Undecylamine, n-dodecylamine, n-tridecylamine, n-tetradecylamine, n-pentadecylamine, n-hexadecylamine, n-heptadecylamine, n-octadecylamine, and n-eicosylamine. Can be mentioned.

The polyamic acid of the present invention and its derivative may further contain a monoisocyanate compound in its monomer. By including the monoisocyanate compound in the monomer, the terminal of the obtained polyamic acid or its derivative is modified and the molecular weight is adjusted. By using this terminal-modified polyamic acid or a derivative thereof, for example, the coating characteristics of the liquid crystal alignment agent can be improved without impairing the effect of the present invention. The content of the monoisocyanate compound in the monomer is preferably 1 to 10 mol% with respect to the total amount of the diamine and the tetracarboxylic dianhydride in the monomer from the above viewpoint. Examples of the monoisocyanate compound include phenyl isocyanate and naphthyl isocyanate.

In the present invention, a polyamic acid having a photoreactive structure and a derivative thereof can be preferably used. Examples of the photoreactive structure include a photoisomerization structure that causes isomerization by irradiation with ultraviolet rays, a photodecomposition structure that causes decomposition, a photodimerization structure that causes dimerization, and the like.

式（Ｐ−１）中、Ｒ^６１は独立して、水素原子、炭素数１〜５のアルキル基、またはフェニル基である。 A polyamic acid having a photoreactive structure and a derivative thereof are designated as the polymer (a). In the polymer (a), a diamine having a photoreactive structure or a tetracarboxylic dianhydride having a photoreactive structure and a derivative thereof can be used as raw materials, and a diamine having a photoreactive structure and a photoreactive structure can be used as raw materials. The tetracarboxylic dianhydride and its derivative may be used in combination. Examples of the photoreactive structure include structures represented by the following formulas (P-1) to (P-7).

In formula (P-1), R ⁶¹ is independently a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a phenyl group.

式（ＰＡ−３）〜式（ＰＡ−６）において、Ｒ^６２は独立して、炭素数１〜５のアルキル基である。 Examples of the compound having a photoreactive structure that causes photodecomposition represented by the formula (P-1) include compounds represented by the following formulas (PA-1) to (PA-6).

In formulas (PA-3) to (PA-6), R ⁶² is independently an alkyl group having 1 to 5 carbon atoms.

Among the compounds represented by the formula (P-1), the above formulas (PA-1), formulas (PA-2) and formulas (PA-5) are preferably used.

The compounds represented by the formulas (PA-1) to (PA-6) are a liquid crystal alignment agent utilizing the liquid crystal alignment ability based on the photoisomerization reaction, a liquid crystal alignment agent utilizing the liquid crystal alignment ability based on photodimerization, or a liquid crystal alignment agent. When used as a material for a liquid crystal alignment agent for rubbing, it is used as a tetracarboxylic acid dianhydride having no photoreactive structure as described above.

Examples of the compound having a photoreactive structure represented by the formulas (P-2) to (P-4) include the tetracarboxylic dianhydride represented by the following formulas (II-1) to (VI-2). Examples include substances and diamine compounds.

上記各式において、環を構成するいずれかの炭素原子に結合位置が固定されていない基は、その環における結合位置が任意であることを示し、式（Ｖ−２）において、Ｒ^６は独立して−ＣＨ_３、−ＯＣＨ_３、−ＣＦ_３、または−ＣＯＯＣＨ_３であり、ａは０〜２の整数であり、式（Ｖ−３）において、環Ａおよび環Ｂは独立して、単環式炭化水素、縮合多環式炭化水素および複素環から選ばれる少なくとも１つであり、Ｒ^１１は、炭素数１〜２０の直鎖アルキレン、−ＣＯＯ−、−ＯＣＯ−、−ＮＨＣＯ−または−Ｎ（ＣＨ_３）ＣＯ−であり、Ｒ^１２は、炭素数１〜２０の直鎖アルキレン、−ＣＯＯ−、−ＯＣＯ−、−ＮＨＣＯ−または−Ｎ（ＣＨ_３）ＣＯ−であり、Ｒ^１１およびＲ^１２において、直鎖アルキレンの−ＣＨ_２−の１つまたは２つは−Ｏ−で置換されてもよく、Ｒ^７〜Ｒ^１０は、独立して、−Ｆ、−ＣＨ_３、−ＯＣＨ_３、−ＣＦ_３、または−ＯＨであり、そして、ｂ〜ｅは、独立して、０〜４の整数である。

In each of the above equations, a group whose bond position is not fixed to any of the carbon atoms constituting the ring indicates that the bond position in the ring is arbitrary, and in the equation (V-2), R ⁶ is independent. Then -CH ₃ , -OCH ₃ , -CF ₃ , or -COOCH ₃ , where a is an integer of 0 to 2, and in equation (V-3), rings A and B are independent and simple. At least one selected from cyclic hydrocarbons, fused polycyclic hydrocarbons and heterocycles, R ¹¹ is a linear alkylene with 1 to 20 carbon atoms, -COO-, -OCO-, -NHCO- or-. N (CH ₃ ) CO-, R ¹² is a linear alkylene with 1 to 20 carbon atoms, -COO-, -OCO-, -NHCO- or -N (CH ₃ ) CO-, R ¹¹ and In R ¹² , one or two of the linear alkylene −CH ₂ − may be substituted with −O −, and R ^{7 to} R ¹⁰ are independently −F, −CH ₃ , −OCH ₃ , -CF ₃ , or -OH, and b to e are independently integers from 0 to 4.

The compounds represented by the above formulas (V-1), (V-2) and (VI-2) can be particularly preferably used from the viewpoint of their photosensitivity. In the formulas (V-2) and (VI-2), the compound in which the binding position of the amino group is in the para position, and in the formula (V-2), the compound having a = 0 is selected from the viewpoint of their orientation. It can be used more preferably.

Tetracarboxylic dianhydrides or diamines having a structure capable of causing photoisomerization by ultraviolet irradiation represented by the formulas (II-1) to (VI-2) are described in the following formulas (II-1) to (VI-2-). It can be expressed concretely in 3).

By using the formulas (VI-1-1) to (V-3-8) as compounds containing a structure capable of causing isomerization by ultraviolet irradiation, a liquid crystal alignment agent for photo-alignment having higher sensitivity to ultraviolet irradiation. Can be obtained. Formula (V-1-1), formula (V-2-1), formula (V-2-4) to formula (V-2-11) and formula (V-3-1) to formula (V-3) By making -8) a compound containing a structure capable of causing isomerization by irradiation with ultraviolet rays, a liquid crystal alignment agent for photo-alignment capable of orienting liquid crystal molecules more uniformly can be obtained. By using the formulas (V-2-4) to (V-3-8) as compounds containing a structure capable of causing isomerization by ultraviolet irradiation, the alignment film formed can be less colored. An orienting agent can be obtained.

Above all, the compound represented by the formula (V-2-1) can be more preferably used because it exhibits greater anisotropy when the liquid crystal alignment film is formed.

式（ＰＤＩ−１２）において、Ｒ^５４は炭素数１〜１０のアルキルまたはアルコキシであり、アルキルまたはアルコキシの少なくとも１つの水素はフッ素に置き換えられていてもよい。 Examples of the compound having a photoreactive structure represented by the formulas (P-5) to (P-7) include diamine compounds represented by the following formulas (PDI-9) to (PDI-13). ..

In formula (PDI-12), R ⁵⁴ is an alkyl or alkoxy having 1 to 10 carbon atoms, and at least one hydrogen of the alkyl or alkoxy may be replaced with fluorine.

The above formulas (PDI-9) and (PDI-11) can be preferably used.

In an embodiment in which a tetracarboxylic dianhydride having no photoreactive structure (non-photosensitive) and a tetracarboxylic dianhydride having a photoreactive structure are used in combination, the sensitivity of the liquid crystal alignment film to light is achieved. The amount of photosensitive tetracarboxylic dianhydride is 0 to 70 mol% with respect to the total amount of tetracarboxylic dianhydride used as a raw material in producing the polyamic acid of the present invention and its derivatives. Preferably, 0 to 50 mol% is particularly preferable. In addition, two or more photosensitive tetracarboxylic dianhydrides may be used in combination in order to improve the above-mentioned various characteristics such as sensitivity to light, electrical characteristics, and afterimage characteristics.

In the embodiment in which a diamine having no photoreactive structure (non-photosensitive) and a diamine having a photoreactive structure (photosensitive) are used in combination, in order to prevent a decrease in the sensitivity of the alignment film to light, the polyamic of the present invention is used. The photosensitive diamine is preferably 20 to 100 mol%, particularly preferably 50 to 100 mol%, based on the total amount of the diamine used as a raw material in producing the acid and its derivative. In addition, two or more photosensitive diamines may be used in combination in order to improve the above-mentioned various characteristics such as sensitivity to light and afterimage characteristics. As described above, the embodiment of the present invention includes the case where the total amount of the tetracarboxylic dianhydride is occupied by the non-photosensitive tetracarboxylic dianhydride, but even in this case, at least 20 mol% of the total amount of the diamine is photosensitive. It is required to be a sex diamine.

In order to improve the above-mentioned various characteristics such as sensitivity to light and afterimage characteristics, photosensitive tetracarboxylic dianhydride and photosensitive diamine may be used in combination, or two or more of each may be used in combination.

The polyamic acid of the present invention and its derivative can be obtained by reacting the above mixture of tetracarboxylic dianhydride with a diamine in a solvent. In this synthetic reaction, no special conditions are required other than the selection of raw materials, and the conditions in ordinary polyamic acid synthesis can be applied as they are. The solvent used will be described later.

The polymer contained in the liquid crystal alignment agent of the present invention may be one or a blend of two or more. In an embodiment in which two or more polymers are blended, at least one of the polymers is the polymer (a) obtained by reacting a raw material monomer in which at least one of tetracarboxylic acid dianhydride and diamine has a photoreactive structure. At least one of the other polymers is selected from polyamic acids and derivatives thereof obtained by reacting a tetracarboxylic acid dianhydride having no photoreactive structure and a diamine having no photoreactive structure. The case of one polymer (b) is included. The structure of the polymer (a) is changed by isomerizing, decomposing or dimerizing the photoreactive structure by irradiation with energy rays such as ultraviolet rays, and the liquid crystal molecules in contact with the polymer film are oriented in a specific direction accordingly. Has the ability to make (photo-orientation). Such polymers may be used by blending with other polymers that do not contain a photoreactive structure.

The liquid crystal alignment agent of the present invention may further contain other components other than the polyamic acid or a derivative thereof. The other components may be one kind or two or more kinds. Examples of other components include other polymers and compounds described later.

When a plurality of polymers are blended and used in the liquid crystal alignment agent of the present invention, the structure and molecular weight of each polymer are controlled, and as described later, the polymer is applied to a substrate and pre-dried to obtain, for example, the above-mentioned light. The polymer (a) having the function of orientation can be separated into the upper layer of the coating film, and the other polymers (b) can be separated into the lower layer of the coating film. This can be controlled by using the phenomenon that the polymer having a small surface energy is separated into the upper layer and the polymer having a large surface energy is separated into the lower layer in the mixed polymer. The layer separation can be confirmed by checking that the surface energy of the formed alignment film is the same as or close to the surface energy of the alignment film formed by the liquid crystal alignment agent containing only the polymer (a).

As the tetracarboxylic dianhydride used for synthesizing the polymer (b), the tetracarboxylic dianhydride used for synthesizing polyamic acid or a derivative thereof, which is an essential component of the liquid crystal alignment agent of the present invention. It can be selected from known tetracarboxylic dianhydrides without limitation, and the same ones as exemplified above can be mentioned.

Among them, in the above-mentioned tetracarboxylic dianhydride, when it is important to improve the layer separability, the formula (AN-3-2), the formula (AN-1-13), and the formula (AN-4-4) are used. 30) is preferable.

When it is important to improve the transmittance of the liquid crystal display element, among the above-mentioned tetracarboxylic dianhydrides, the formula (AN-1-1), the formula (AN-1-2), and the formula (PA-) 1), formula (AN-3-1), formula (AN-4-17), formula (AN-4-30), formula (AN-5-1), formula (AN-7-2), formula ( Compounds represented by AN-10-1), formula (AN-10-2), formula (AN-16-3), and formula (AN-16-4) are preferred. In the formula (AN-1-2), m = 4 or 8 is preferable. In the formula (AN-4-17), m = 4 or 8 is preferable, and m = 8 is more preferable.

When it is important to improve the VHR of the liquid crystal display element, among the above-mentioned tetracarboxylic dianhydrides, the formula (PA-1), the formula (AN-4-17), and the formula (AN-7-2) ), Equation (AN-10-1), Equation (AN-10-2), Equation (AN-16-1), Equation (AN-16-3) and Equation (AN-16-4). Compounds are preferred. In the formula (AN-1-2) and the formula (AN-4-17), m = 4 or 8 is preferable.

Improving the relaxation rate of the residual charge (residual DC) in the alignment film by reducing the volume resistance value of the liquid crystal alignment film is effective as one of the methods for preventing seizure. When this purpose is emphasized, among the above-mentioned tetracarboxylic dianhydrides, the formula (AN-1-13), the formula (AN-3-2), the formula (AN-4-21), and the formula (AN) -4-29) and the compound represented by the formula (AN-11-3) are preferable.

The tetracarboxylic dianhydride used for synthesizing the polymer (b) preferably contains an aromatic tetracarboxylic dianhydride in an amount of 10 mol% or more based on the total tetracarboxylic dianhydride. More preferably, it contains 30 mol% or more.

The diamine and dihydrazide used for synthesizing the polymer (b) are exemplified above as other diamines that can be used for synthesizing the polyamic acid which is an essential component of the liquid crystal alignment agent of the present invention or a derivative thereof. The same thing can be mentioned.

Among the above diamines and dihydrazides, among the above diamines and dihydrazides, the formulas (DI-4-1), formulas (DI-4-2), and formulas are for the purpose of further improving the layer separability, that is, the orientation of the liquid crystal. Compounds represented by (DI-4-10), formula (DI-5-1), formula (DI-5-9), formula (DI-5-28), and formula (DIH-2-1). It is preferable to use it. In the formula (DI-5-1), m = 1, 2, or 4 is preferable, and m = 1, or 2 is more preferable.

Of the above diamines and dihydrazides, the formula (DI-1-2), the formula (DI-2-1), the formula (DI-5-1), and the formula It is preferable to use the diamine represented by (DI-7-3), and the diamine represented by the formula (DI-2-1) is more preferable. In the formula (DI-5-1), m = 1, 2, or 4 is preferable, and m = 1, or 2 is more preferable. In the formula (DI-7-3), m = 2 or 3, n = 1 or 2, is preferable, and m = 1 is more preferable.

When it is important to improve the VHR of the liquid crystal display element, among the above diamines and dihydrazides, the formula (DI-2-1), the formula (DI-4-1), and the formula (DI-4-2) , Equation (DI-4-15), Equation (DI-5-1), Equation (DI-5-28), Equation (DI-5-30), Equation (DI-13-1) and Equation (DI- It is preferable to use the diamine represented by 31-56). The diamine represented by the formula (DI-2-1), the formula (DI-5-1), the formula (DI-13-1) and the formula (DI-36-14) is more preferable. In the formula (DI-5-1), m = 1 or 2 is preferable. In the formula (DI-5-30), k = 2 is preferable.

Improving the relaxation rate of the residual charge (residual DC) in the alignment film by reducing the volume resistance value of the liquid crystal alignment film is effective as one of the methods for preventing seizure. When this purpose is emphasized, among the above diamines and dihydrazides, the formula (DI-4-1), the formula (DI-4-2), the formula (DI-4-10), and the formula (DI-4-10) 15), Eq. (DI-5-1), Eq. (DI-5-9), Eq. (DI-5-12), Eq. (DI-5-13), Eq. (DI-5-28), Eq. (DI-5-28) It is preferable to use the compound represented by the formula (DI-5-30) and the formula (DI-16-1), and the formula (DI-4-1), the formula (DI-5-1), and the formula (DI-). The diamine represented by 5-12) is more preferable. In the formula (DI-5-1), m = 1 or 2 is preferable. In the formula (DI-5-12), m = 2-6 is preferable, and m = 5 is more preferable. In the formula (DI-5-13), m = 1 or 2 is preferable, and m = 1 is more preferable. In the formula (DI-5-30), k = 2 is preferable.

The diamine used for synthesizing the polymer (b) preferably contains an aromatic diamine in an amount of 30 mol% or more, more preferably 50 mol% or more, based on the total diamine.

In the liquid crystal aligning agent of the present invention, the ratio of the polymer (a) to the total amount of the polymer (a) and the polymer (b) is preferably 10% by weight to 100% by weight, and further 20% by weight to 100% by weight. preferable.

The liquid crystal alignment agent of the present invention may further contain other components other than the polyamic acid of the present invention or a derivative thereof. The other components may be one kind or two or more kinds. Examples of other components include other polymers and compounds described later.

Examples of other polymers include polyester, polyamide, polysiloxane, cellulose derivative, polyacetal, polystyrene derivative, poly (styrene-phenylmaleimide) derivative, poly (meth) acrylate and the like. It may be one kind or two or more kinds. Of these, polysiloxane is preferred.

Examples of the polysiloxane include JP-A-2009-036966, JP-A-2010-185001, JP-A-2011-102963, JP-A-2011-253175, JP-A-2012-159825, International Publication 2008/044644, International Publication 2009/1480099, International Publication. It is disclosed in 2010/074261, International Publication 2010/074264, International Publication 2010/126108, International Publication 2011/068123, International Publication 2011/068127, International Publication 2011/068128, International Publication 2012/115157, International Publication 2012/165354, etc. It can further contain the present polysiloxane.

Further, the liquid crystal alignment agent of the present invention may contain an additive. Examples thereof include alkenyl-substituted nadiimide compounds, oxazine compounds, oxazoline compounds, epoxy compounds, high molecular weight compounds other than polyamic acid and its derivatives, and other low molecular weight compounds, which can be selected and used according to their respective purposes. ..

<Alkenyl-substituted nadiimide compound>
The liquid crystal alignment agent of the present invention may further contain an alkenyl-substituted nadiimide compound for the purpose of stabilizing the electrical characteristics of the liquid crystal display element for a long period of time. The alkenyl-substituted nadiimide compound may be used alone or in combination of two or more. For the above purpose, the content of the alkenyl-substituted nadiimide compound is preferably 1 to 100% by weight, more preferably 1 to 70% by weight, and 1 to 50% by weight with respect to the polyamic acid or its derivative. Is more preferable.

式（ＮＡ）において、Ｌ^１およびＬ^２は独立して水素、炭素数１〜１２のアルキル、炭素数３〜６のアルケニル、炭素数５〜８のシクロアルキル、炭素数６〜１２のアリールまたはベンジルであり、ｎは１または２である。 The nadiimide compound will be specifically described below.
The alkenyl-substituted nadiimide compound is preferably a compound that can be dissolved in a solvent that dissolves the polyamic acid or its derivative used in the present invention. Examples of such an alkenyl-substituted nadiimide compound include a compound represented by the following formula (NA).

In formula (NA), L ¹ and L ² are independently hydrogen, alkyl with 1 to 12 carbon atoms, alkenyl with 3 to 6 carbon atoms, cycloalkyl with 5 to 8 carbon atoms, aryl with 6 to 12 carbon atoms or It is benzyl and n is 1 or 2.

In the formula (NA), when n = 1, W is an alkyl having 1 to 12 carbon atoms, an alkenyl having 2 to 6 carbon atoms, a cycloalkyl having 5 to 8 carbon atoms, an aryl having 6 to 12 carbon atoms, benzyl, and −. Z ¹ − (O) _r − (Z ² O) _{k −} Z ³ −H (where Z ¹ , Z ² and Z ³ are independently alkylenes having 2 to 6 carbon atoms, and r is 0 or 1 And k is an integer of 1 to 30),-(Z ⁴ ) _r- B-Z ^5- H (where Z ⁴ and Z ⁵ are independent carbon atoms). A group represented by an alkylene of 1 to 4 or a cycloalkylene having 5 to 8 carbon atoms, where B is a phenylene and r is 0 or 1), -BT-B-H (here). And B is phenylene, and T is represented by -CH _2- , -C (CH ₃ ) _2- , -O-, -CO-, -S-, or -SO _2- ). A group, or a group in which 1 to 3 hydrogens of these groups are substituted with -OH.

At this time, preferable W is alkyl having 1 to 8 carbon atoms, alkenyl having 3 to 4 carbon atoms, cyclohexyl, phenyl, benzyl, poly (ethyleneoxy) ethyl having 4 to 10 carbon atoms, phenyloxyphenyl, phenylmethylphenyl, and the like. Phenylisopropylidenephenyl, and one or two hydrogens of these groups replaced with -OH.

In the formula (NA), when n = 2, W is an alkylene having 2 to 20 carbon atoms, a cycloalkylene having 5 to 8 carbon atoms, an arylene having 6 to 12 carbon atoms, and −Z ¹ −O− (Z ² O). _{A group represented by k-} Z ^3- (where Z ^{1 to} Z ³ and k are defined as described above), -Z ^4- B-Z ^5- (where Z ⁴ , Z). defining ⁵ and B are as defined above. groups represented _{by), -B- (O-B)} r -T- (B-O) r -B- ( wherein, B is phenylene, T is alkylene of 1 to 3 carbon atoms, -O- or -SO ₂ -. a is a group defined for r is represented by are as defined above) or 1-3 hydrogen of these groups, A group replaced by −OH.

In this case, W is preferably an alkylene having 2 to 12 carbon atoms, cyclohexylene, phenylene, tolylene, ^{_{xylylene, -C 3 H 6 -O- (Z}} 2 -O) n -O-C 3 H 6 - ( wherein, Z ² is an alkylene having 2 to 6 carbon atoms and n is 1 or 2), a group represented by -B-TB- (where B is phenylene and T is-). A group represented by CH _2- , -O- or -SO _2- ), -B-OB-C ₃ H _6- B-OB- (where B is phenylene. ), And one or two hydrogens of these groups replaced with -OH.

Such an alkenyl-substituted nadiimide compound is synthesized by holding an alkenyl-substituted nadicic acid anhydride derivative and a diamine at a temperature of 80 to 220 ° C. for 0.5 to 20 hours, for example, as described in Japanese Patent 272965. A compound obtained from the above or a commercially available compound can be used. Specific examples of the alkenyl-substituted nadiimide compound include the following compounds.

N-Methyl-allylbicyclo [2.2.1] hept-5-en-2,3-dicarboxyimide, N-methyl-allylmethylbicyclo [2.2.1] hept-5-en-2,3 -Dicarboxyimide, N-methyl-metharylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N-methyl-metharylmethylbicyclo [2.2.1] hept- 5-en-2,3-dicarboxyimide, N- (2-ethylhexyl) -allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide,

N- (2-ethylhexyl) -allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N-allyl-allylbicyclo [2.2.1] hept-5 -En-2,3-dicarboxyimide, N-allyl-allylmethylbicyclo [2.2.1] Hept-5-ene-2,3-dicarboxyimide, N-allyl-metharylbicyclo [2.2] .1] Hept-5-en-2,3-dicarboxyimide, N-isopropenyl-allylbicyclo [2.2.1] Hept-5-en-2,3-dicarboxyimide, N-isopropenyl- Allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N-isopropenyl-metharylbicyclo [2.2.1] hept-5-en-2,3 -Dicarboxyimide, N-cyclohexyl-allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N-cyclohexyl-allyl (methyl) bicyclo [2.2.1] hept- 5-en-2,3-dicarboxyimide, N-cyclohexyl-metharylbicyclo [2.2.1] Hept-5-ene-2,3-dicarboxyimide, N-phenyl-allylbicyclo [2.2] .1] Hept-5-en-2,3-dicarboxyimide,

N-phenyl-allyl (methyl) bicyclo [2.2.1] hept-5-en-2,3-dicarboxyimide, N-benzyl-allylbicyclo [2.2.1] hept-5-en-2 , 3-Dicarboxyimide, N-benzyl-allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N-benzyl-metharylbicyclo [2.2.1] hept -5-en-2,3-dicarboxyimide, N- (2-hydroxyethyl) -allylbicyclo [2.2.1] Hept-5-ene-2,3-dicarboxyimide, N- (2-) Hydroxyethyl) -allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N- (2-hydroxyethyl) -metharylbicyclo [2.2.1] hept -5-en-2,3-dicarboxyimide,

N- (2,2-dimethyl-3-hydroxypropyl) -allylbicyclo [2.2.1] hepto-5-ene-2,3-dicarboxyimide, N- (2,2-dimethyl-3-hydroxy) Propyl) -allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N- (2,3-dihydroxypropyl) -allylbicyclo [2.2.1] hept -5-en-2,3-dicarboxyimide, N- (2,3-dihydroxypropyl) -allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N- (3-Hydroxy-1-propenyl) -allyl bicyclo [2.2.1] hepto-5-ene-2,3-dicarboxyimide, N- (4-hydroxycyclohexyl) -allyl (methyl) bicyclo [ 2.2.1] Hept-5-en-2,3-dicarboxyimide,

N- (4-Hydroxyphenyl) -allyl bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N- (4-hydroxyphenyl) -allyl (methyl) bicyclo [2.2] .1] Hept-5-en-2,3-dicarboxyimide, N- (4-hydroxyphenyl) -metharylbicyclo [2.2.1] Hept-5-en-2,3-dicarboxyimide, N- (4-Hydroxyphenyl) -Metalylmethylbicyclo [2.2.1] Hept-5-ene-2,3-dicarboxyimide, N- (3-Hydroxyphenyl) -allylbicyclo [2.2. 1] Hept-5-ene-2,3-dicarboxyimide, N- (3-hydroxyphenyl) -allyl (methyl) bicyclo [2.2.1] Hept-5-en-2,3-dicarboxyimide , N- (p-hydroxybenzyl) -allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N- {2- (2-hydroxyethoxy) ethyl} -allylbicyclo [ 2.2.1] Hept-5-en-2,3-dicarboxyimide,

N- {2- (2-hydroxyethoxy) ethyl} -allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N- {2- (2-hydroxyethoxy) ) Ethyl} -Metalrylbicyclo [2.2.1] Hept-5-ene-2,3-dicarboxyimide, N- {2- (2-hydroxyethoxy) ethyl} -Metalylmethylbicyclo [2.2] .1] Hept-5-ene-2,3-dicarboxyimide, N- [2- {2- (2-hydroxyethoxy) ethoxy} ethyl] -allylbicyclo [2.2.1] hept-5-ene -2,3-dicarboxyimide, N- [2- {2- (2-hydroxyethoxy) ethoxy} ethyl] -allyl (methyl) bicyclo [2.2.1] hept-5-ene-2,3- Dicarboxyimide, N- [2- {2- (2-hydroxyethoxy) ethoxy} ethyl] -metharylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N- { 4- (4-Hydroxyphenylisopropyridene) phenyl} -allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide, N- {4- (4-hydroxyphenylisopropyridene) phenyl } -Allyl (methyl) bicyclo [2.2.1] Hept-5-ene-2,3-dicarboxyimide, N- {4- (4-hydroxyphenylisopropylidene) phenyl} -Metalyl bicyclo [2. 2.1] Hept-5-ene-2,3-dicarboxyimide, and oligomers thereof,

N, N'-ethylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-ethylene-bis (allylmethylbicyclo [2.2.]. 1] Hept-5-en-2,3-dicarboxyimide), N, N'-ethylene-bis (Metalylbicyclo [2.2.1] Hept-5-en-2,3-dicarboxyimide) , N, N'-trimethylen-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-hexamethylene-bis (allylbicyclo [2.2] .1] Hept-5-en-2,3-dicarboxyimide), N, N'-hexamethylene-bis (allylmethylbicyclo [2.2.1] hept-5-en-2,3-dicarboxyimide) Imid), N, N'-dodecamethylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-dodecamethylene-bis (allylmethylbicyclo) [2.2.1] Hept-5-en-2,3-dicarboxyimide), N, N'-cyclohexylene-bis (allylbicyclo [2.2.1] Hept-5-en-2,3) -Dicarboxyimide), N, N'-cyclohexylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide),

1,2-bis {3'-(allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) propoxy} ethane, 1,2-bis {3'-(allylmethylbicyclo) [2.2.1] Hept-5-ene-2,3-dicarboxyimide) propoxy} ethane, 1,2-bis {3'-(metharylbicyclo [2.2.1] hept-5-ene) -2,3-dicarboxyimide) propoxy} ethane, bis [2'-{3'-(allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) propoxy} ethyl] Ether, bis [2'-{3'-(allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) propoxy} ethyl] ether, 1,4-bis {3' -(Allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) propoxy} butane, 1,4-bis {3'-(allylmethylbicyclo [2.2.1] hept -5-en-2,3-dicarboxyimide) propoxy} butane,

N, N'-p-phenylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-p-phenylene-bis (allylmethylbicyclo [2.2.1] 2.2.1] Hept-5-en-2,3-dicarboxyimide), N, N'-m-phenylene-bis (allylbicyclo [2.2.1] hept-5-en-2,3 -Dicarboxyimide), N, N'-m-phenylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-{(1) -Methyl) -2,4-phenylene} -bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-p-xylylene-bis (allylbicyclo) [2.2.1] Hept-5-en-2,3-dicarboxyimide), N, N'-p-xylylene-bis (allylmethylbicyclo [2.2.1] hept-5-en-2) , 3-Dicarboxyimide), N, N'-m-xylylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-m- Xylylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide),

2,2-bis [4- {4- (allylbicyclo [2.2.1] hepto-5-ene-2,3-dicarboxyimide) phenoxy} phenyl] propane, 2,2-bis [4- { 4- (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) phenoxy} phenyl] propane, 2,2-bis [4- {4- (metalrylbicyclo [2] .2.1] Hept-5-ene-2,3-dicarboxyimide) phenoxy} phenyl] propane, bis {4- (allylbicyclo [2.2.1] hept-5-en-2,3-di Carboxyimide) phenyl} methane, bis {4- (allylmethylbicyclo [2.2.1] hepto-5-ene-2,3-dicarboxyimide) phenyl} methane,

Bis {4- (metalrylbicyclo [2.2.1] hept-5-en-2,3-dicarboxyimide) phenyl} methane, bis {4- (metallylmethylbicyclo [2.2.1] hept -5-en-2,3-dicarboxyimide) phenyl} methane, bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) phenyl} ether, bis {4- (Allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) phenyl} ether, bis {4- (Metalylmethylbicyclo [2.2.1] hept-5) -En-2,3-dicarboxyimide) phenyl} ether, bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) phenyl} sulfone, bis {4 -(Allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) phenyl} sulfone,

Bis {4- (methallylbicyclo [2.2.1] hept-5-en-2,3-dicarboxyimide) phenyl} sulfone, 1,6-bis (allylbicyclo [2.2.1] hept- 5-en-2,3-dicarboxyimide) -3-hydroxy-hexane, 1,12-bis (methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide)- 3,6-dihydroxy-dodecane, 1,3-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) -5-hydroxy-cyclohexane, 1,5-bis { 3'-(allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) propoxy} -3-hydroxy-pentane, 1,4-bis (allylbicyclo [2.2.1] ] Hept-5-ene-2,3-dicarboxyimide) -2-hydroxy-benzene,

1,4-Bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) -2,5-dihydroxy-benzene, N, N'-p- (2-hydroxy) ) Xylylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-p- (2-hydroxy) xylylene-bis (allylmethylcyclo [2]) .2.1] Hept-5-ene-2,3-dicarboxyimide), N, N'-m- (2-hydroxy) xylylene-bis (allylbicyclo [2.2.1] hept-5-ene) -2,3-dicarboxyimide), N, N'-m- (2-hydroxy) xylylene-bis (metharylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) , N, N'-p- (2,3-dihydroxy) xylylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide),

2,2-Bis [4- {4- (allylbicyclo [2.2.1] hepto-5-ene-2,3-dicarboxyimide) -2-hydroxy-phenoxy} phenyl] Propane, bis {4- (Allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) -2-hydroxy-phenyl} methane, bis {3- (allylbicyclo [2.2.1] hept- 5-en-2,3-dicarboxyimide) -4-hydroxy-phenyl} ether, bis {3- (methallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) -5-Hydroxy-phenyl} sulfone, 1,1,1-tri {4- (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide)} phenoxymethylpropane, N , N', N "-tri (ethylenemetallylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) isocyanurate, and oligomers thereof.

Further, the alkenyl-substituted nadiimide compound used in the present invention may be a compound represented by the following formula having an asymmetric group containing an alkylene and a phenylene group.

Among the alkenyl-substituted nadiimide compounds, preferable compounds are shown below.
N, N'-ethylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-ethylene-bis (allylmethylbicyclo [2.2.]. 1] Hept-5-en-2,3-dicarboxyimide), N, N'-ethylene-bis (Metalylbicyclo [2.2.1] Hept-5-en-2,3-dicarboxyimide) , N, N'-trimethylen-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-hexamethylene-bis (allylbicyclo [2.2] .1] Hept-5-en-2,3-dicarboxyimide), N, N'-hexamethylene-bis (allylmethylbicyclo [2.2.1] hept-5-en-2,3-dicarboxyimide) Imid), N, N'-dodecamethylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-dodecamethylene-bis (allylmethylbicyclo) [2.2.1] Hept-5-en-2,3-dicarboxyimide), N, N'-cyclohexylene-bis (allylbicyclo [2.2.1] Hept-5-en-2,3) -Dicarboxyimide), N, N'-cyclohexylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide),

N, N'-p-phenylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-p-phenylene-bis (allylmethylbicyclo [2.2.1] 2.2.1] Hept-5-en-2,3-dicarboxyimide), N, N'-m-phenylene-bis (allylbicyclo [2.2.1] hept-5-en-2,3 -Dicarboxyimide), N, N'-m-phenylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-{(1) -Methyl) -2,4-phenylene} -bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-p-xylylene-bis (allylbicyclo) [2.2.1] Hept-5-en-2,3-dicarboxyimide), N, N'-p-xylylene-bis (allylmethylbicyclo [2.2.1] hept-5-en-2) , 3-Dicarboxyimide), N, N'-m-xylylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-m- Xylylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), 2,2-bis [4- {4- (allylbicyclo [2.2.1]] Hept-5-en-2,3-dicarboxyimide) phenoxy} phenyl] propane, 2,2-bis [4- {4- (allylmethylbicyclo [2.2.1] hept-5-en-2, 3-Dicarboxyimide) phenoxy} phenyl] propane, 2,2-bis [4- {4- (metalrylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) phenoxy} Phenyl] Propane, bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) phenyl} methane, bis {4- (allylmethylbicyclo [2.2.1] ] Hept-5-ene-2,3-dicarboxyimide) phenyl} methane,

Bis {4- (Metalyl bicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) phenyl} methane, Bis {4- (Metalyl methyl bicyclo [2.2.1] hept -5-en-2,3-dicarboxyimide) phenyl} methane, bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) phenyl} ether, bis {4- (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) phenyl} ether, bis {4- (metalrylbicyclo [2.2.1] hept-5) -En-2,3-dicarboxyimide) phenyl} ether, bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) phenyl} sulfone, bis {4 -(Allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) phenyl} sulfone, bis {4- (metharylbicyclo [2.2.1] hept-5-ene) -2,3-dicarboxyimide) phenyl} sulfone.

More preferred alkenyl-substituted nadiimide compounds are shown below.
N, N'-ethylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-ethylene-bis (allylmethylbicyclo [2.2.]. 1] Hept-5-en-2,3-dicarboxyimide), N, N'-ethylene-bis (Metalylbicyclo [2.2.1] Hept-5-en-2,3-dicarboxyimide) , N, N'-trimethylen-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-hexamethylene-bis (allylbicyclo [2.2] .1] Hept-5-en-2,3-dicarboxyimide), N, N'-hexamethylene-bis (allylmethylbicyclo [2.2.1] hept-5-en-2,3-dicarboxyimide) Imid), N, N'-dodecamethylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-dodecamethylene-bis (allylmethylbicyclo) [2.2.1] Hept-5-en-2,3-dicarboxyimide), N, N'-cyclohexylene-bis (allylbicyclo [2.2.1] Hept-5-en-2,3) -Dicarboxyimide), N, N'-cyclohexylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide),

N, N'-p-phenylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-p-phenylene-bis (allylmethylbicyclo [2.2.1] 2.2.1] Hept-5-en-2,3-dicarboxyimide), N, N'-m-phenylene-bis (allylbicyclo [2.2.1] hept-5-en-2,3 -Dicarboxyimide), N, N'-m-phenylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-{(1) -Methyl) -2,4-phenylene} -bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-p-xylylene-bis (allylbicyclo) [2.2.1] Hept-5-en-2,3-dicarboxyimide), N, N'-p-xylylene-bis (allylmethylbicyclo [2.2.1] hept-5-en-2) , 3-Dicarboxyimide), N, N'-m-xylylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide), N, N'-m- Xylylene-bis (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide),

2,2-bis [4- {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) phenoxy} phenyl] propane, 2,2-bis [4- { 4- (Allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) phenoxy} phenyl] propane, 2,2-bis [4- {4- (metalrylbicyclo [2] .2.1] Hept-5-ene-2,3-dicarboxyimide) phenoxy} phenyl] propane, bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-di Carboxyimide) phenyl} methane, bis {4- (allylmethylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) phenyl} methane, bis {4- (metalrylbicyclo [2] .2.1] Hept-5-en-2,3-dicarboxyimide) phenyl} methane, bis {4- (Metalylmethylbicyclo [2.2.1] Hept-5-en-2,3-di Carboximide) phenyl} methane.

A particularly preferable alkenyl-substituted nadiimide compound is bis {4- (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) represented by the following formula (NA-1). Phenyl} methane, N, N'-m-xylylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) represented by the formula (NA-2), and Examples thereof include N, N'-hexamethylene-bis (allylbicyclo [2.2.1] hept-5-ene-2,3-dicarboxyimide) represented by the formula (NA-3).

<Compound with radically polymerizable unsaturated double bond>
The liquid crystal aligning agent of the present invention may further contain a compound having a radically polymerizable unsaturated double bond for the purpose of stabilizing the electrical characteristics of the liquid crystal display element for a long period of time. The compound having a radically polymerizable unsaturated double bond may be one kind of compound or two or more kinds of compounds. The compound having a radically polymerizable unsaturated double bond does not include an alkenyl-substituted nadiimide compound. For the above purpose, the content of the compound having a radically polymerizable unsaturated double bond is preferably 1 to 100% by weight, more preferably 1 to 70% by weight, based on the polyamic acid or a derivative thereof. It is preferably 1 to 50% by weight, more preferably 1 to 50% by weight.

The ratio of the compound having a radically polymerizable unsaturated double bond to the alkenyl-substituted nadiimide compound reduces the ion density of the liquid crystal display element, suppresses the increase of the ion density with time, and further suppresses the generation of afterimages. Therefore, the compound / alkenyl-substituted nadiimide compound having a radically polymerizable unsaturated double bond is preferably 0.1 to 10 by weight, more preferably 0.5 to 5.

The compound having a radically polymerizable unsaturated double bond will be specifically described below.
Examples of the compound having a radically polymerizable unsaturated double bond include (meth) acrylic acid ester, (meth) acrylic acid derivative such as (meth) acrylic acid amide, and bismaleimide. The compound having a radically polymerizable unsaturated double bond is more preferably a (meth) acrylic acid derivative having two or more radically polymerizable unsaturated double bonds.

Specific examples of the (meth) acrylic acid ester include, for example, cyclohexyl (meth) acrylate, -2-methylcyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, and dicyclopentanyl (meth) acrylate. Examples thereof include oxyethyl, isobolonyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, -2-hydroxyethyl (meth) acrylate, and -2-hydroxypropyl (meth) acrylate.

Specific examples of the bifunctional (meth) acrylic acid ester include ethylene bisacrylate, Aronix M-210, Aronix M-240 and Aronix M-6200, which are products of Toa Synthetic Chemical Industry Co., Ltd., and Nippon Kayaku Co., Ltd. ) Products KAYARADHDDA, KAYARADHX-220, KAYARADR-604 and KAYARADR-684, V260, V312 and V335HP products of Osaka Organic Chemical Industry Co., Ltd., and light acrylate products of Kyoeisha Oil & Fat Chemical Industry Co., Ltd. BA-4EA, light acrylate BP-4PA and light acrylate BP-2PA can be mentioned.

Specific examples of the trifunctional or higher functional polyfunctional (meth) acrylic acid ester include 4,4'-methylenebis (N, N-dihydroxyethylene acrylate aniline) and Aronix M-, which is a product of Toa Synthetic Chemical Industry Co., Ltd. 400, Aronix M-405, Aronix M-450, Aronix M-7100, Aronix M-8030, Aronix M-8060, KAYARADTMPTA, KAYARADDPCA-20, KAYARADDPCA-30, KAYARADDPCA-60, which are products of Nippon Kayaku Co., Ltd. , KAYARADDPCA-120, and VGPT, which is a product of Osaka Organic Chemical Industry Co., Ltd.

Specific examples of the (meth) acrylic acid amide derivative include, for example, N-isopropylacrylamide, N-isopropylmethacrylamide, Nn-propylacrylamide, Nn-propylmethacrylamide, N-cyclopropylacrylamide, and N-cyclopropyl. Methulamide, N-ethoxyethylacrylamide, N-ethoxyethylmethacrylamide, N-tetrahydrofurfurylacrylamide, N-tetrahydrofurfurylmethacrylamide, N-ethylacrylamide, N-ethyl-N-methylacrylamide, N, N-diethyl Acrylamide, N-methyl-N-n-propylacrylamide, N-methyl-N-isopropylacrylamide, N-acrylloylpiperidin, N-acrylloylpyrrolidin, N, N'-methylenebisacrylamide, N, N'-ethylenebisacrylamide, N, N'-dihydroxyethylenebisacrylamide, N- (4-hydroxyphenyl) methacrylamide, N-phenylmethacrylamide, N-butylmethacrylate, N- (iso-butoxymethyl) methacrylamide, N- [2-( N, N-dimethylamino) ethyl] methacrylicamide, N, N-dimethylmethamido, N- [3- (dimethylamino) propyl] methacrylicamide, N- (methoxymethyl) methacrylicamide, N- (hydroxymethyl)- Examples include 2-methacrylamide, N-benzyl-2-methacrylamide, and N, N'-methylenebismethacrylamide.

Among the above (meth) acrylic acid derivatives, N, N'-methylenebisacrylamide, N, N'-dihydroxyethylene-bisacrylamide, ethylenebis acrylate, and 4,4'-methylenebis (N, N-dihydroxyethylene acrylate) Aniline) is particularly preferable.

Examples of bismaleimide include BMI-70 and BMI-80 manufactured by KI Kasei Co., Ltd., and BMI-1000, BMI-3000, BMI-4000, BMI-5000 and BMI- manufactured by Daiwa Kasei Kogyo Co., Ltd. 7000 is mentioned.

<Oxazine compound>
The liquid crystal aligning agent of the present invention may further contain an oxazine compound for the purpose of stabilizing the electrical characteristics of the liquid crystal display element for a long period of time. The oxazine compound may be one kind of compound or two or more kinds of compounds. For the above purpose, the content of the oxazine compound is preferably 0.1 to 50% by weight, more preferably 1 to 40% by weight, and 1 to 20% by weight with respect to the polyamic acid or its derivative. Is more preferable.

The oxazine compound will be specifically described below.
The oxazine compound is soluble in a solvent that dissolves the polyamic acid or a derivative thereof, and in addition, an oxazine compound having ring-opening polymerizable property is preferable.

The number of oxazine structures in the oxazine compound is not particularly limited.

Various structures are known for the structure of oxazine. In the present invention, the structure of oxazine is not particularly limited, and examples of the oxazine structure in the oxazine compound include the structure of oxazine having an aromatic group including a condensed polycyclic aromatic group such as benzoxazine and naphthoxazine.

式（ＯＸ−１）〜式（ＯＸ−３）において、Ｌ^３およびＬ^４は炭素数１〜３０の有機基であり、式（ＯＸ−１）〜式（ＯＸ−６）において、Ｌ^５〜Ｌ^８は水素または炭素数１〜６の炭化水素基であり、式（ＯＸ−３）、式（ＯＸ−４）および式（ＯＸ−６）において、Ｑ^１は単結合、−Ｏ−、−Ｓ−、−Ｓ−Ｓ−、−ＳＯ_２−、−ＣＯ−、−ＣＯＮＨ−、−ＮＨＣＯ−、−Ｃ（ＣＨ_３）_２−、−Ｃ（ＣＦ_３）_２−、−（ＣＨ_２）_ｖ−、−Ｏ−（ＣＨ_２）_ｖ−Ｏ−、−Ｓ−（ＣＨ_２）_ｖ−Ｓ−であり、ここでｖは１〜６の整数であり、式（ＯＸ−５）および式（ＯＸ−６）において、Ｑ^２は独立して単結合、−Ｏ−、−Ｓ−、−ＣＯ−、−Ｃ（ＣＨ_３）_２−、−Ｃ（ＣＦ_３）_２−または炭素数１〜３のアルキレンであり、式（ＯＸ−１）〜式（ＯＸ−６）におけるベンゼン環、ナフタレン環に結合している水素は独立して−Ｆ、−ＣＨ_３、−ＯＨ、−ＣＯＯＨ、−ＳＯ_３Ｈ、−ＰＯ_３Ｈ_２と置き換えられていてもよい。 Examples of the oxazine compound include compounds represented by the following formulas (OX-1) to (OX-6). In the following formula, the bond displayed toward the center of the ring indicates that the bond constitutes a ring and is bonded to any carbon capable of bonding a substituent.

In the formula (OX-1) ~ formula ^{(OX-3), L} 3 and ^{L 4} is an organic group having 1 to 30 carbon atoms, in the formula (OX-1) ~ formula ^{(OX-6), L 5} ~ L ⁸ is hydrogen or a hydrocarbon group having 1 to 6 carbon atoms, and in the formula (OX-3), the formula (OX-4) and the formula (OX-6), Q ¹ is a single bond, −O−, −. S-, -S-S-, -SO _2- , -CO-, -CONH-, -NHCO-, -C (CH ₃ ) _2- , -C (CF ₃ ) ₂ -,-(CH ₂ ) _v -, -O- (CH ₂ ) _v- O-, -S- (CH ₂ ) _v -S-, where v is an integer of 1-6, in equations (OX-5) and (OX-5). in -6), ^{Q 2} is independently a single bond, -O -, - S -, - CO -, - C (CH 3) 2 -, - C (CF 3) 2 - or 1 to 3 carbon atoms Hydrogen that is alkylene and is bonded to the benzene ring and naphthalene ring in the formulas (OX-1) to (OX-6) is independently -F, -CH ₃ , -OH, -COOH, -SO ₃ H. , -PO ₃ H ₂ may be replaced.

Further, the oxazine compound includes an oligomer or polymer having an oxazine structure in the side chain, and an oligomer or polymer having an oxazine structure in the main chain.

式（ＯＸ−１−２）において、Ｌ^３は炭素数１〜３０のアルキルが好ましく、炭素数１〜２０のアルキルがさらに好ましい。 Examples of the oxazine compound represented by the formula (OX-1) include the following oxazine compounds.

In the formula (OX-1-2), ^{L 3} is preferably an alkyl having 1 to 30 carbon atoms, more preferably alkyl of 1 to 20 carbon atoms.

Examples of the oxazine compound represented by the formula (OX-2) include the following oxazine compounds.

式中、Ｌ^３は炭素数１〜３０のアルキルが好ましく、炭素数１〜２０のアルキルがさらに好ましい。

In the formula, L ³ is preferably an alkyl having 1 to 30 carbon atoms, and more preferably an alkyl having 1 to 20 carbon atoms.

式（ＯＸ−３−Ｉ）において、Ｌ^３およびＬ^４は炭素数１〜３０の有機基であり、Ｌ^５からＬ^８は水素または炭素数１〜６の炭化水素基であり、Ｑ^１は単結合、−ＣＨ_２−、−Ｃ（ＣＨ_３）_２−、−ＣＯ−、−Ｏ−、−ＳＯ_２−、−Ｃ（ＣＨ_３）_２−、または−Ｃ（ＣＦ_３）_２−である。式（ＯＸ−３−Ｉ）で表されるオキサジン化合物としては、例えば以下のオキサジン化合物が挙げられる。 Examples of the oxazine compound represented by the formula (OX-3) include an oxazine compound represented by the following formula (OX-3-I).

In the formula (OX-3-I), L ³ and L ⁴ are organic groups having 1 to 30 carbon atoms, L ⁵ to L ⁸ are hydrogen or hydrocarbon groups having 1 to 6 carbon atoms, and Q ¹ is Single bond, -CH _2- , -C (CH ₃ ) _2- , -CO- _{, -O-, -SO 2-} , -C (CH ₃ ) _2- , or -C (CF ₃ ) _2-. .. Examples of the oxazine compound represented by the formula (OX-3-I) include the following oxazine compounds.

式中、Ｌ^３およびＬ^４は炭素数１〜３０のアルキルが好ましく、炭素数１〜２０のアルキルがさらに好ましい。

In the formula, L ³ and L ⁴ are preferably alkyl having 1 to 30 carbon atoms, and more preferably alkyl having 1 to 20 carbon atoms.

Examples of the oxazine compound represented by the formula (OX-4) include the following oxazine compounds.

Examples of the oxazine compound represented by the formula (OX-5) include the following oxazine compounds.

Examples of the oxazine compound represented by the formula (OX-6) include the following oxazine compounds.

Of these, more preferably, the formula (OX-2-1), the formula (OX-3-1), the formula (OX-3-3), the formula (OX-3-5), and the formula (OX-3-3). 7), Equation (OX-3-9), Equation (OX-4-1) to Equation (OX-4-6), Equation (OX-5-3), Equation (OX-5-4), and Equation. Examples thereof include oxazine compounds represented by the formulas (OX-6-2) to (OX-6-4).

The oxazine compound can be produced by the same method as described in International Publication 2004/09708, JP-A-11-12258, and JP-A-2004-352670.

The oxazine compound represented by the formula (OX-1) is obtained by reacting a phenol compound with a primary amine and an aldehyde (see International Publication 2004/09708).

The oxazine compound represented by the formula (OX-2) is obtained by reacting by gradually adding a primary amine to formaldehyde, and then adding a compound having a naphthol-based hydroxyl group and reacting (International Publication 2004 /). See 090708.).

The oxazine compound represented by the formula (OX-3) contains 1 mol of a phenol compound, at least 2 mol or more of an aldehyde per phenolic hydroxyl group thereof, and 1 mol of a primary amine as a secondary aliphatic compound in an organic solvent. It is obtained by reacting in the presence of an amine, a tertiary aliphatic amine or a basic nitrogen-containing heterocyclic compound (see International Publication 2004/09708 and JP-A-11-12258).

The oxazine compounds represented by the formulas (OX-4) to (OX-6) include diamines, formalins, etc. having a plurality of benzene rings and an organic group that binds them, such as 4,4'-diaminodiphenylmethane. It is obtained by subjecting aldehyde and phenol to a dehydration condensation reaction in n-butyl alcohol at a temperature of 90 ° C. or higher (see JP-A-2004-352670).

<Oxazoline compound>
The liquid crystal aligning agent of the present invention may further contain an oxazoline compound for the purpose of stabilizing the electrical characteristics of the liquid crystal display element for a long period of time. An oxazoline compound is a compound having an oxazoline structure. The oxazoline compound may be one kind of compound or two or more kinds of compounds. For the above purpose, the content of the oxazoline compound is preferably 0.1 to 50% by weight, more preferably 1 to 40% by weight, and 1 to 20% by weight with respect to the polyamic acid or its derivative. Is more preferable. Alternatively, the content of the oxazoline compound is preferably 0.1 to 40% by weight based on the polyamic acid or a derivative thereof when the oxazoline structure in the oxazoline compound is converted into oxazoline.

The oxazoline compound will be specifically described below.
The oxazoline compound may have only one type of oxazoline structure in one compound, or may have two or more types. Further, the oxazoline compound may have one oxazoline structure in one compound, but preferably has two or more oxazoline structures. Further, the oxazoline compound may be a polymer having an oxazoline structure in a side chain or a copolymer. The polymer having an oxazoline structure in the side chain may be a homopolymer of a monomer having an oxazoline structure in the side chain, or may be a copolymer of a monomer having an oxazoline structure in the side chain and a monomer having no oxazoline structure. Good. The copolymer having an oxazoline structure in the side chain may be a copolymer of two or more kinds of monomers having an oxazoline structure in the side chain, or two or more kinds of monomers having an oxazoline structure in the side chain and a monomer having no oxazoline structure. It may be a copolymer with.

The oxazoline structure is preferably a structure that is present in the oxazoline compound so that one or both of oxygen and nitrogen in the oxazoline structure can react with the carbonyl group of the polyamic acid.

Examples of the oxazoline compound include 2,2'-bis (2-oxazoline), 1,2,4-tris- (2-oxazoline-2) -benzene, 4-furan-2-ylmethylene-2-phenyl-4H-. Oxazoline-5-one, 1,4-bis (4,5-dihydro-2-oxazoline) benzene, 1,3-bis (4,5-dihydro-2-oxazoline) benzene, 2,3-bis (4-4-bis) Isopropenyl-2-oxazoline-2-yl) butane, 2,2'-bis-4-benzyl-2-oxazoline, 2,6-bis (isopropyl-2-oxazoline-2-yl) pyridine, 2,2' -Isopropyridenebis (4-tert-butyl-2-oxazoline), 2,2'-isopropyridenebis (4-phenyl-2-oxazoline), 2,2'-methylenebis (4-tert-butyl-2-oxazoline) ), And 2,2'-methylenebis (4-phenyl-2-oxazoline). In addition to these, polymers and oligomers having oxazolyl such as Epocross (trade name, manufactured by Nippon Shokubai Co., Ltd.) can also be mentioned. Of these, 1,3-bis (4,5-dihydro-2-oxazolyl) benzene is more preferable.

<Epoxy compound>
The liquid crystal alignment agent of the present invention may further contain an epoxy compound for the purpose of stabilizing the electrical characteristics of the liquid crystal display element for a long period of time. The epoxy compound may be one kind of compound or two or more kinds of compounds. For the above purpose, the content of the epoxy compound is preferably 0.1 to 50% by weight, more preferably 1 to 40% by weight, and 1 to 20% by weight with respect to the polyamic acid or its derivative. Is more preferable.

The epoxy compound will be specifically described below.
Examples of the epoxy compound include various compounds having one or more epoxy rings in the molecule. Examples of the compound having one epoxy ring in the molecule include phenylglycidyl ether, butylglycidyl ether, 3,3,3-trifluoromethylpropylene oxide, styrene oxide, hexafluoropropylene oxide, cyclohexene oxide, and 3-glycidoxy. Propyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, N-glycidylphthalimide, (nonafluoro-N-butyl) epoxide, perfluoroethylglycidyl ether, epichlorohydrin, epibromohydrin, Examples include N, N-diglycidylaniline, and 3- [2- (perfluorohexyl) ethoxy] -1,2-epoxide propane.

Examples of the compound having two epoxy rings in the molecule include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, and neopentyl glycol diglycidyl. Ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, 3,4-epoxycyclohexenylmethyl-3', 4'-epoxycyclohexene carboxylate and 3 -(N, N-diglycidyl) aminopropyltrimethoxysilane can be mentioned.

Examples of the compound having three epoxy rings in the molecule include 2- [4- (2,3-epoxypropoxy) phenyl] -2- [4- [1,1-bis] 4-([2,3-]. Epoxy propoxy] phenyl)] ethyl] phenyl] propane (trade name "Techmore VG3101L", (manufactured by Mitsui Kagaku Co., Ltd.)) can be mentioned.

Examples of the compound having four epoxy rings in the molecule include 1,3,5,6-tetraglycidyl-2,4-hexanediol, N, N, N', N'-tetraglycidyl-m-xylene diamine, and the like. 1,3-Bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N', N'-tetraglycidyl-4,4'-diaminodiphenylmethane, and 3- (N-allyl-N-glycidyl) Aminopropyltrimethoxysilane is mentioned.

In addition to the above, examples of compounds having an epoxy ring in the molecule include oligomers and polymers having an epoxy ring. Monomers having an epoxy ring include, for example, glycidyl (meth) acrylate, 3,4-epoxycyclohexyl (meth) acrylate, and methylglycidyl (meth) acrylate.

Other monomers that copolymerize with the monomer having an epoxy ring include, for example, (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, and iso-butyl. (Meta) acrylate, t-butyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, styrene, methylstyrene, chlormethyl Examples include styrene, (3-ethyl-3-oxetanyl) methyl (meth) acrylate, N-cyclohexyl maleimide and N-phenylmaleimide.

Preferred specific examples of the polymer of the monomer having an epoxy ring include polyglycidyl methacrylate and the like. Moreover, as a preferable specific example of a copolymer of a monomer having an epoxy ring and another monomer, N-phenylmaleimide-glycidyl methacrylate copolymer, N-cyclohexyl maleimide-glycidyl methacrylate copolymer, benzyl methacrylate-glycidyl methacrylate copolymer, butyl methacrylate-glycidyl Included are methacrylate copolymers, 2-hydroxyethyl methacrylate-glycidyl methacrylate copolymers, (3-ethyl-3-oxetanyl) methyl methacrylate-glycidyl methacrylate copolymers and styrene-glycidyl methacrylate copolymers.

Among these examples, N, N, N', N'-tetraglycidyl-m-xylene diamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N', N' -Tetraglycidyl-4,4'-diaminodiphenylmethane, trade name "Techmore VG3101L", 3,4-epoxycyclohexenylmethyl-3', 4'-epoxycyclohexene carboxylate, N-phenylmaleimide-glycidyl methacrylate copolymer, and 2 -(3,4-Epoxycyclohexyl) ethyltrimethoxysilane is particularly preferred.

More systematically, the epoxy compounds include, for example, glycidyl ether, glycidyl ester, glycidyl amine, epoxy group-containing acrylic resin, glycidyl amide, glycidyl isocyanurate, chain aliphatic epoxy compound, and cyclic aliphatic epoxy compound. Can be mentioned. The epoxy compound means a compound having an epoxy group, and the epoxy resin means a resin having an epoxy group.

Examples of the epoxy compound include glycidyl ether, glycidyl ester, glycidyl amine, epoxy group-containing acrylic resin, glycidyl amide, glycidyl isocyanurate, chain aliphatic epoxy compound, and cyclic aliphatic epoxy compound.

Examples of the glycidyl ether include bisphenol A type epoxy compound, bisphenol F type epoxy compound, bisphenol S type epoxy compound, bisphenol type epoxy compound, hydride bisphenol-A type epoxy compound, hydride bisphenol-F type epoxy compound, and hydride bisphenol. -S type epoxy compound, hydrogenated bisphenol type epoxy compound, brominated bisphenol-A type epoxy compound, brominated bisphenol-F type epoxy compound, phenol novolac type epoxy compound, cresol novolac type epoxy compound, brominated phenol novolac type epoxy compound , Brominated cresol novolac type epoxy compound, bisphenol A novolac type epoxy compound, naphthalene skeleton containing epoxy compound, aromatic polyglycidyl ether compound, dicyclopentadienephenol type epoxy compound, alicyclic diglycidyl ether compound, aliphatic polyglycidyl ether Examples include compounds, polysulfide-type diglycidyl ether compounds, and biphenol-type epoxy compounds.

Examples of the glycidyl ester include a diglycidyl ester compound and a glycidyl ester epoxy compound.

Examples of the glycidylamine include a polyglycidylamine compound and a glycidylamine type epoxy resin.

Examples of the epoxy group-containing acrylic compound include homopolymers and copolymers of monomers having oxylanyl.

Examples of the glycidyl amide include a glycidyl amide type epoxy compound.

Examples of the chain aliphatic epoxy compound include an epoxy group-containing compound obtained by oxidizing a carbon-carbon double bond of an alkene compound.

Examples of the cyclic aliphatic epoxy compound include compounds containing an epoxy group obtained by oxidizing the carbon-carbon double bond of a cycloalkene compound.

Examples of the bisphenol A type epoxy compound include jER828, jER1001, jER1002, jER1003, jER1004, jER1007, jER1010 (trade names, manufactured by Mitsubishi Chemicals, Inc.), Epototo YD-128 (manufactured by Toto Kasei Co., Ltd.), and DER. -331, DER-332, DER-324 (all manufactured by The Dow Chemical Company), Epicron 840, Epicron 850, Epicron 1050 (trade name, all manufactured by DIC Co., Ltd.), Epomic R-140, Epomic R-301 , And Epoxy R-304 (both trade names, manufactured by Mitsui Chemicals, Inc.).

Examples of the bisphenol F type epoxy compound include jER806, jER807, and jER4004P (trade names, all manufactured by Mitsubishi Chemical Corporation), Epototo YDF-170, Epototo YDF-175S, and Epototo YDF-2001 (all trade names, Toto Kasei). DER-354 (trade name, manufactured by The Dow Chemical Company), Epicron 830, and Epicron 835 (trade name, all manufactured by DIC Co., Ltd.).

Examples of the bisphenol type epoxy compound include an epoxy compound of 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane.

Examples of the hydrogenated bisphenol-A type epoxy compound include Santoto ST-3000 (trade name, manufactured by Toto Kasei Co., Ltd.), Ricaresin HBE-100 (trade name, manufactured by Shin Nihon Rika Co., Ltd.), and Denacol EX-252. (Product name, manufactured by Nagase ChemteX Corporation) can be mentioned.

Examples of the hydrogenated bisphenol type epoxy compound include an epoxidized product of hydrogenated 2,2-bis (4-hydroxyphenyl) -1,1,1,3,3,3-hexafluoropropane.

Examples of the brominated bisphenol-A type epoxy compound include jER5050, jER5051 (trade name, manufactured by Mitsubishi Chemical Corporation), Epototo YDB-360, and Epototo YDB-400 (trade name, all manufactured by Toto Kasei Co., Ltd.). ), DER-530, DER-538 (all trade names, manufactured by The Dow Chemical Company), Epicron 152, and Epicron 153 (all trade names, manufactured by DIC Co., Ltd.).

Examples of the phenol novolac type epoxy compound include jER152, jER154 (trade name, manufactured by Mitsubishi Chemical Co., Ltd.), YDPN-638 (trade name, manufactured by Toto Kasei Co., Ltd.), DEN431, and DEN438 (trade name, all manufactured by The Dow). Chemical Company), Epicron N-770 (trade name, manufactured by DIC Co., Ltd.), EPPN-201, and EPPN-202 (trade name, all manufactured by Nippon Kayaku Co., Ltd.).

Examples of the cresol novolac type epoxy compound include jER180S75 (trade name, manufactured by Mitsubishi Chemical Corporation), YDCN-701, YDCN-702 (trade name, manufactured by Toto Kasei Co., Ltd.), Epicron N-665, and Epicron N-695. (All trade names, manufactured by DIC Co., Ltd.), EOCN-102S, EOCN-103S, EOCN-104S, EOCN-1020, EOCN-1025, and EOCN-1027 (all trade names, manufactured by Nippon Kayaku Co., Ltd.) ).

Examples of the bisphenol A novolak type epoxy compound include jER157S70 (trade name, manufactured by Mitsubishi Chemical Corporation) and Epicron N-880 (trade name, manufactured by DIC Corporation).

Examples of the naphthalene skeleton-containing epoxy compound include Epicron HP-4032, Epicron HP-4700, Epicron HP-4770 (trade name, manufactured by DIC Corporation), and NC-7000 (trade name, manufactured by Nippon Kayaku Co., Ltd.). Can be mentioned.

Examples of the aromatic polyglycidyl ether compound include hydroquinone diglycidyl ether (formula EP-1 below), catechol diglycidyl ether (formula EP-2 below), resorcinol diglycidyl ether (formula EP-3 below), 2- [4. -(2,3-epoxypropoxy) phenyl] -2- [4- [1,1-bis [4-([2,3-epoxypropoxy] phenyl)] ethyl] phenyl] propane (formula EP-4 below) , Tris (4-glycidyloxyphenyl) methane (formula EP-5 below), jER1031S, jER1032H60 (trade name, manufactured by Mitsubishi Chemical Corporation), TACTIX-742 (trade name, manufactured by The Dow Chemical Company), Denacol EX-201 (trade name, manufactured by Nagase ChemteX Corporation), DPPN-503, DPPN-502H, DPPN-501H, NC6000 (trade name, manufactured by Nippon Kayaku Co., Ltd.), Techmore VG3101L (trade name, manufactured by Nippon Kayaku Co., Ltd.) Examples thereof include a compound represented by the following formula EP-6 and a compound represented by the following formula EP-7 (manufactured by Mitsui Chemicals, Inc.).

Examples of the dicyclopentadienephenol type epoxy compound include TACTIX-556 (trade name, manufactured by The Dow Chemical Company) and Epicron HP-7200 (trade name, manufactured by DIC Corporation).

Examples of the alicyclic diglycidyl ether compound include a cyclohexanedimethanol diglycidyl ether compound and Ricaresin DME-100 (trade name, manufactured by Shin Nihon Rika Co., Ltd.).

Examples of the aliphatic polyglycidyl ether compound include ethylene glycol diglycidyl ether (formula EP-8 below), diethylene glycol diglycidyl ether (formula EP-9 below), polyethylene glycol diglycidyl ether, and propylene glycol diglycidyl ether (formula EP-8 below). -10), Tripropylene glycol diglycidyl ether (formula EP-11 below), polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether (formula EP-12 below), 1,4-butanediol diglycidyl ether (formula below) EP-13), 1,6-hexanediol diglycidyl ether (formula EP-14 below), dibromoneopentyl glycol diglycidyl ether (formula EP-15 below), Denacol EX-810, Denacol EX-851, Denacol EX- 8301, Denacol EX-911, Denacol EX-920, Denacol EX-931, Denacol EX-211, Denacol EX-212, Denacol EX-313 (trade names, all manufactured by Nagase ChemteX Corporation), DD-503 (all manufactured by Nagase ChemteX Corporation) Product name, ADEKA Co., Ltd., Rica Resin W-100 (trade name, manufactured by Shin Nihon Rika Co., Ltd.), 1,3,5,6-tetraglycidyl-2,4-hexanediol (formula EP-16 below) ), Glycerin polyglycidyl ether, sorbitol polyglycidyl ether, trimethylpropan polyglycidyl ether, pentaerythritol polyglycidyl ether, Denacol EX-313, Denacol EX-611, Denacol EX-321, and Denacol EX-411 (all trade names). , Made by Nagase ChemteX Corporation).

Examples of the polysulfide-type diglycidyl ether compound include FLDP-50 and FLDP-60 (both trade names, manufactured by Toraythiocol Co., Ltd.).

Examples of biphenol type epoxy compounds include YX-4000, YL-6121H (trade name, manufactured by Mitsubishi Chemical Corporation), NC-3000P, and NC-3000S (trade name, all manufactured by Nippon Kayaku Co., Ltd.). ).

Examples of the diglycidyl ester compound include diglycidyl terephthalate (formula EP-17 below), diglycidyl phthalate (formula EP-18 below), bis (2-methyloxylanylmethyl) phthalate (formula EP-19 below), and diglycidyl ester compounds. Examples thereof include glycidyl hexahydrophthalate (the following formula EP-20), a compound represented by the following formula EP-21, a compound represented by the following formula EP-22, and a compound represented by the following formula EP-23.

Examples of the glycidyl ester epoxy compound include jER871, jER872 (trade name, manufactured by Mitsubishi Chemical Corporation), Epicron 200, Epicron 400 (trade name, all manufactured by DIC Corporation), Denacol EX-711, and Denacol. EX-721 (trade name, manufactured by Nagase ChemteX Corporation) can be mentioned.

Examples of the polyglycidylamine compound include N, N-diglycidylaniline (formula EP-24 below), N, N-diglycidyl-o-toluidine (formula EP-25 below), and N, N-diglycidyl-m-toluidine (formula EP-24 below). The following formula EP-26), N, N-diglycidyl-2,4,6-tribromoaniline (the following formula EP-27), 3- (N, N-diglycidyl) aminopropyltrimethoxysilane (the following formula EP-28) ), N, N, O-triglycidyl-p-aminophenol (formula EP-29 below), N, N, O-triglycidyl-m-aminophenol (formula EP-30 below), N, N, N' , N'-tetraglycidyl-4,4'-diaminodiphenylmethane (formula EP-31 below), N, N, N', N'-tetraglycidyl-m-xylylene diamine (TETRAD-X (trade name, Mitsubishi Gas) Chemical Co., Ltd.), the following formula EP-32), 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane (TETRAD-C (trade name, manufactured by Mitsubishi Gas Chemicals Co., Ltd.), the following formula EP -33), 1,4-bis (N, N-diglycidylaminomethyl) cyclohexane (formula EP-34 below), 1,3-bis (N, N-diglycidylamino) cyclohexane (formula EP-35 below) , 1,4-bis (N, N-diglycidylamino) cyclohexane (formula EP-36 below), 1,3-bis (N, N-diglycidylamino) benzene (formula EP-37 below), 1,4 -Bis (N, N-diglycidylamino) benzene (formula EP-38 below), 2,6-bis (N, N-diglycidylaminomethyl) bicyclo [2.2.1] heptane (formula EP-39 below) ), N, N, N', N'-tetraglycidyl-4,4'-diaminodicyclohexylmethane (formula EP-40 below), 2,2'-dimethyl- (N, N, N', N'-tetra Glycidyl) -4,4'-diaminobiphenyl (formula EP-41 below), N, N, N', N'-tetraglycidyl-4,4'-diaminodiphenyl ether (formula EP-42 below), 1,3 5-Tris (4- (N, N-diglycidyl) aminophenoxy) benzene (formula EP-43 below), 2,4,4'-tris (N, N-diglycidylamino) diphenyl ether (formula EP-44 below) , Tris (4- (N, N-diglycidyl) aminophenyl) methane (formula EP-45 below), 3,4,3', 4'-tetrakis (N, N-diglycidylamino) biphenyl (formula below) EP-46), 3,4,3', 4'-tetrakis (N, N-diglycidylamino) diphenyl ether (the following formula EP-47), the compound represented by the following formula EP-48, and the following formula EP- Examples include the compound represented by 49.

Examples of homopolymers of monomers having oxylanyl include polyglycidyl methacrylate. Examples of copolymers of monomers having oxylanyl include N-phenylmaleimide-glycidyl methacrylate copolymer, N-cyclohexyl maleimide-glycidyl methacrylate copolymer, benzyl methacrylate-glycidyl methacrylate copolymer, butyl methacrylate-glycidyl methacrylate copolymer, and 2-hydroxyethyl methacrylate-glycidyl methacrylate copolymer. Examples include copolymers, (3-ethyl-3-oxetanyl) methyl methacrylate-glycidyl methacrylate copolymers, and styrene-glycidyl methacrylate copolymers.

Monomers having oxylanyl include, for example, glycidyl (meth) acrylate, 3,4-epoxycyclohexyl (meth) acrylate, and methylglycidyl (meth) acrylate.

Examples of the monomers other than the monomer having oxylanyl in the copolymer of the monomer having oxylanyl include (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, and butyl (meth) acrylate. iso-butyl (meth) acrylate, t-butyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, styrene, methylstyrene , Chlormethylstyrene, (3-ethyl-3-oxetanyl) methyl (meth) acrylate, N-cyclohexylmaleimide, and N-phenylmaleimide.

Examples of glycidyl isocyanurate include 1,3,5-triglycidyl-1,3,5-triazine-2,4,6- (1H, 3H, 5H) -trione (the following formula EP-50), 1,3. Examples thereof include −diglycidyl-5-allyl-1,3,5-triazine-2,4,6- (1H, 3H, 5H) -trione (formula EP-51 below), and glycidyl isocyanurate-type epoxy resin.

Examples of the chain aliphatic epoxy compound include epoxidized polybutadiene and Epolide PB3600 (trade name, manufactured by Daicel Corporation).

Examples of the cyclic aliphatic epoxy compound include 3,4-epoxycyclohexenylmethyl-3', 4'-epoxycyclohexene carboxylate (celloxide 2021 (manufactured by Daicel Co., Ltd.), the following formula EP-52), 2-methyl. -3,4-Epoxycyclohexylmethyl-2'-methyl-3', 4'-epoxycyclohexylcarboxylate (EP-53 below), 2,3-epoxycyclopentane-2', 3'-epoxycyclopentane ether (Epoxy-54 below), ε-caprolactone-modified 3,4-epoxycyclohexylmethyl-3', 4'-epoxycyclohexanecarbochelate, 1,2: 8,9-diepoxy limonene (celloxide 3000 (trade name, (trade name,)) (Manufactured by Daicel Co., Ltd.), the following formula EP-55), the compound represented by the following formula EP-56, CY-175, CY-177, CY-179 (trade name, all manufactured by The Ciba-Geigy Chemical Corp. (Available from Huntsman Japan Co., Ltd.)), EHPD-3150 (trade name, manufactured by Daicel Co., Ltd.), and cyclic aliphatic epoxy resins.

The epoxy compound is preferably one or more of a polyglycidylamine compound, a bisphenol A novolac type epoxy compound, a cresol novolac type epoxy compound, and a cyclic aliphatic type epoxy compound, and is N, N, N', N'-tetraglycidyl. -M-xylene diamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N', N'-tetraglycidyl-4,4'-diaminodiphenylmethane, trade name "Techmore VG3101L" , 3,4-Epoxycyclohexenylmethyl-3', 4'-epoxycyclohexene carboxylate, N-phenylmaleimide-glycidyl methacrylate copolymer, N, N, O-triglycidyl-p-aminophenol, bisphenol A novolac type epoxy compound , And one or more of the cresol novolac type epoxy compounds.

Further, for example, the liquid crystal alignment agent of the present invention may further contain various additives. Examples of various additives include high molecular weight compounds other than polyamic acid and its derivatives, and low molecular weight compounds, which can be selected and used according to their respective purposes.

Examples of the polymer compound include polymer compounds that are soluble in organic solvents. It is preferable to add such a polymer compound to the liquid crystal alignment agent of the present invention from the viewpoint of controlling the electrical characteristics and orientation of the formed liquid crystal alignment film. Examples of the polymer compound include polyamide, polyurethane, polyurea, polyester, polyepoxyside, polyester polyol, silicone-modified polyurethane, and silicone-modified polyester.

The low molecular weight compounds include, for example, 1) a surfactant for the purpose when improvement in coatability is desired, 2) an antistatic agent when improvement in antistatic property is required, and 3) adhesion to a substrate. Examples thereof include a silane coupling agent and a titanium-based coupling agent when improvement is desired, and 4) an imidization catalyst when imidization proceeds at a low temperature.

Examples of the silane coupling agent include vinyltrimethoxysilane, vinyltriethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, and N- (2-aminoethyl) -3-aminopropylmethyltri. Methoxysilane, paraaminophenyltrimethoxysilane, paraaminophenyltriethoxysilane, metaaminophenyltrimethoxysilane, metaaminophenyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxy Propyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, N- Examples thereof include (1,3-dimethylbutylidene) -3- (triethoxysilyl) -1-propylamine, and N, N'-bis [3- (trimethoxysilyl) propyl] ethylenediamine. A preferred silane coupling agent is 3-aminopropyltriethoxysilane.

Examples of the imidization catalyst include aliphatic amines such as trimethylamine, triethylamine, tripropylamine and tributylamine; aromatic amines such as N, N-dimethylaniline, N, N-diethylaniline, methyl-substituted aniline and hydroxy-substituted aniline. Kind: Cylindrical amines such as pyridine, methyl-substituted pyridine, hydroxy-substituted pyridine, quinoline, methyl-substituted quinoline, hydroxy-substituted quinoline, isoquinoline, methyl-substituted isoquinoline, hydroxy-substituted isoquinolin, imidazole, methyl-substituted imidazole, and hydroxy-substituted imidazole. .. The imidization catalyst may be one or more selected from N, N-dimethylaniline, o-, m-, p-hydroxyaniline, o-, m-, p-hydroxypyridine, and isoquinoline. preferable.

The amount of the silane coupling agent added is usually 0 to 20% by weight, preferably 0.1 to 10% by weight, based on the total weight of the polyamic acid or its derivative.

The amount of the imidization catalyst added is usually 0.01 to 5 equivalents, preferably 0.05 to 3 equivalents, relative to the carbonyl group of the polyamic acid or its derivative.

The amount of the other additives added varies depending on the intended use, but is usually 0 to 100% by weight, preferably 0.1 to 50% by weight, based on the total weight of the polyamic acid or its derivative.

The polyamic acid of the present invention or a derivative thereof can be produced in the same manner as a known polyamic acid or a derivative thereof used for forming a polyimide film. The total amount of tetracarboxylic dianhydride charged is preferably approximately the same molar number as the total number of moles of diamine (molar ratio of about 0.9 to 1.1).

The molecular weight of the polyamic acid or its derivative of the present invention is preferably 7,000 to 500,000, more preferably 10,000 to 200,000 in terms of polystyrene-equivalent weight average molecular weight (Mw). The molecular weight of the polyamic acid or a derivative thereof can be determined by measurement by a gel permeation chromatography (GPC) method.

The existence of the polyamic acid of the present invention or a derivative thereof can be confirmed by analyzing the solid content obtained by precipitating with a large amount of a poor solvent by IR or NMR. Further, the monomer used can be confirmed by analyzing the extract of the decomposition product of the polyamic acid or its derivative with an organic solvent of a strong alkaline aqueous solution such as KOH or NaOH by GC, HPLC or GC-MS. it can.

Further, for example, the liquid crystal alignment agent of the present invention may further contain a solvent from the viewpoint of the coatability of the liquid crystal alignment agent and the adjustment of the concentration of the polyamic acid or its derivative. The solvent can be applied without any particular limitation as long as it is a solvent having an ability to dissolve a polymer component. The solvent includes a wide range of solvents usually used in the manufacturing process and application of polymer components such as polyamic acid and soluble polyimide, and can be appropriately selected depending on the purpose of use. The solvent may be one kind or a mixed solvent of two or more kinds.

The concentration of the polyamic acid or its derivative in the alignment agent of the present invention is preferably 0.1 to 40% by weight. When the alignment agent is applied to the substrate, it may be necessary to dilute the contained polyamic acid with a solvent in advance in order to adjust the film thickness.

The solid content concentration in the alignment agent of the present invention is not particularly limited, and the optimum value may be selected according to the various coating methods described below. Usually, it is preferably 0.1 to 30% by weight, more preferably 1 to 10% by weight, based on the weight of the varnish in order to suppress unevenness, pinholes and the like during coating.

The viscosity of the liquid crystal aligning agent of the present invention varies in a preferable range depending on the method of application, the concentration of the polyamic acid or its derivative, the type of the polyamic acid or its derivative used, and the type and ratio of the solvent. For example, in the case of coating by a printing machine, it is 5 to 100 mPa · s (more preferably 10 to 80 mPa · s). If it is less than 5 mPa · s, it becomes difficult to obtain a sufficient film thickness, and if it exceeds 100 mPa · s, printing unevenness may become large. In the case of application by spin coating, 5 to 200 mPa · s (more preferably 10 to 100 mPa · s) is suitable. When coating using an inkjet coating device, 5 to 50 mPa · s (more preferably 5 to 20 mPa · s) is suitable. The viscosity of the liquid crystal aligning agent is measured by a rotational viscosity measuring method, and is measured using, for example, a rotational viscometer (TVE-20L type manufactured by Toki Sangyo Co., Ltd.) (measurement temperature: 25 ° C.).

The liquid crystal alignment film of the present invention will be described in detail. The liquid crystal alignment film of the present invention is a film formed by heating the coating film of the liquid crystal alignment agent of the present invention described above. The liquid crystal alignment film of the present invention can be obtained by a usual method for producing a liquid crystal alignment film from a liquid crystal alignment agent. For example, the liquid crystal alignment film of the present invention can be obtained through a step of forming a coating film of the liquid crystal alignment agent of the present invention, a step of heating and drying, and a step of heating and firing. As for the liquid crystal alignment film of the present invention, as described later, the film obtained through the heat drying step and the heat firing step may be subjected to a rubbing treatment to impart anisotropy. Alternatively, if necessary, anisotropy may be imparted by irradiating light after the coating step and the heat drying step, or by irradiating the light after the heating and firing step. It may also be used as a liquid crystal alignment film for VA that is not subjected to rubbing treatment.

The coating film can be formed by applying the liquid crystal alignment agent of the present invention to the substrate of the liquid crystal display element in the same manner as in the production of a normal liquid crystal alignment film. The _{substrate, ITO (IndiumTinOxide), IZO (} In 2 O 3 -ZnO), include _{IGZO (In-Ga-ZnO 4} ) electrodes and color filters glass substrate may be provided with such electrode ..

As a method of applying the liquid crystal alignment agent to the substrate, a spinner method, a printing method, a dipping method, a dropping method, an inkjet method and the like are generally known. These methods are similarly applicable to the present invention.

As the heat-drying step, a method of heat-treating in an oven or an infrared furnace, a method of heat-treating on a hot plate, and the like are generally known. The heat-drying step is preferably carried out at a temperature within a range in which the solvent can be evaporated, and more preferably carried out at a temperature relatively lower than the temperature in the heating-baking step. Specifically, the heating and drying temperature is preferably in the range of 30 ° C. to 150 ° C., and more preferably in the range of 50 ° C. to 120 ° C.

The heating and firing step can be performed under the conditions necessary for the polyamic acid or a derivative thereof to exhibit a dehydration / ring closure reaction. For firing the coating film, a method of heat-treating in an oven or an infrared furnace, a method of heat-treating on a hot plate, and the like are generally known. These methods are similarly applicable in the present invention. Generally, it is preferably carried out at a temperature of about 100 to 300 ° C. for 1 minute to 3 hours, more preferably 120 to 280 ° C., and even more preferably 150 to 250 ° C. Moreover, it can be heated and fired a plurality of times at different temperatures. A plurality of heating devices set to different temperatures may be used, or one heating device may be used to sequentially change the temperature to different temperatures. When the heating and firing are performed twice at different temperatures, it is preferable that the first time is performed at a temperature of 90 to 180 ° C. and the second time is performed at a temperature of 185 ° C. or higher.

In the method for forming a liquid crystal alignment film of the present invention, a rubbing method, a photoalignment method, and the like are known as means for imparting anisotropy to the alignment film in order to orient the liquid crystal in one direction with respect to the horizontal and / or vertical directions. Can be preferably used.

The liquid crystal alignment film of the present invention using the rubbing method includes a step of applying the liquid crystal alignment agent of the present invention to a substrate, a step of heating and drying the substrate to which the alignment agent is applied, a step of heating and firing the film, and a film. Can be formed through a step of rubbing.

The rubbing treatment can be performed in the same manner as the rubbing treatment for the normal liquid crystal alignment film alignment treatment, and the conditions may be such that sufficient retardation can be obtained in the liquid crystal alignment film of the present invention. Preferred conditions are a bristles pushing amount of 0.2 to 0.8 mm, a stage moving speed of 5 to 250 mm / sec, and a roller rotation speed of 500 to 2,000 rpm.

The method for forming the liquid crystal alignment film of the present invention by the photoalignment method will be described in detail. The liquid crystal alignment film of the present invention using the photoalignment method imparts anisotropy to the coating film by irradiating the coating film with linearly polarized light or non-polarized radiation after heating and drying the coating film, and heat-fires the film. It can be formed by Alternatively, it can be formed by heating and drying the coating film, heating and firing, and then irradiating with linearly polarized radiation or non-polarized radiation. From the viewpoint of orientation, it is preferable that the radiation irradiation step is performed before the heating and firing step.

Further, in order to increase the liquid crystal alignment ability of the liquid crystal alignment film, it is possible to irradiate the coating film with linearly polarized or unpolarized radiation while heating the coating film. Irradiation may be performed in a step of heating and drying the coating film or a step of heating and firing, or may be performed between the heating and drying step and the heating and firing step. The heating and drying temperature in the step is preferably in the range of 30 ° C. to 150 ° C., more preferably in the range of 50 ° C. to 120 ° C. Further, the heating and firing temperature in the step is preferably in the range of 30 ° C. to 300 ° C., more preferably in the range of 50 ° C. to 250 ° C.

As the radiation, for example, ultraviolet rays containing light having a wavelength of 150 to 800 nm or visible light can be used, but ultraviolet rays containing light having a wavelength of 300 to 400 nm are preferable. Further, linearly polarized light or unpolarized light can be used. These lights are not particularly limited as long as they can impart a liquid crystal alignment ability to the coating film, but linearly polarized light is preferable when it is desired to exert a strong orientation regulating force on the liquid crystal.

The liquid crystal alignment film of the present invention can exhibit high liquid crystal alignment ability even when irradiated with low energy light. Dose of linearly polarized light in the irradiation step is preferably from 0.05~20J / cm ^2, more preferably 0.5~10J / cm ^2. The wavelength of linearly polarized light is preferably 200 to 400 nm, more preferably 300 to 400 nm. The irradiation angle of the linearly polarized light on the film surface is not particularly limited, but when it is desired to exert a strong orientation-regulating force on the liquid crystal, it is preferable that the linearly polarized light is perpendicular to the film surface as much as possible from the viewpoint of shortening the orientation processing time. Further, the liquid crystal alignment film of the present invention can orient the liquid crystal in a direction perpendicular to the polarization direction of the linearly polarized light by irradiating it with linearly polarized light.

The light irradiated to the film when the pretilt angle is desired to be expressed may be linearly polarized light or unpolarized light as described above. Dose of light applied to the film when it is desired to express a pre-tilt angle is preferably from 0.05~20J / cm ^2, particularly preferably 0.5~10J / cm ^2, its wavelength is 250 It is preferably 400 nm, and particularly preferably 300 to 380 nm. When the pretilt angle is desired to be expressed, the irradiation angle of the light irradiating the film with respect to the film surface is not particularly limited, but is preferably 30 to 60 degrees from the viewpoint of shortening the orientation processing time.

Light sources used in the process of irradiating linearly polarized or unpolarized radiation include ultra-high pressure mercury lamps, high pressure mercury lamps, low pressure mercury lamps, Deep UV lamps, halogen lamps, metal halide lamps, high power metal halide lamps, xenon lamps, and mercury. Xenon lamps, excimer lamps, KrF excimer lasers, fluorescent lamps, LED lamps, sodium lamps, microwave-excited electrodeless lamps, and the like can be used without limitation.

The liquid crystal alignment film of the present invention can be preferably obtained by a method further including steps other than the above-mentioned steps. For example, the liquid crystal alignment film of the present invention does not require a step of cleaning the film after firing or irradiation with a cleaning liquid, but a cleaning step can be provided for the convenience of other steps.

Examples of the cleaning method using a cleaning liquid include brushing, jet spraying, steam cleaning, ultrasonic cleaning and the like. These methods may be performed alone or in combination. As the cleaning liquid, pure water or various alcohols such as methyl alcohol, ethyl alcohol and isopropyl alcohol, aromatic hydrocarbons such as benzene, toluene and xylene, halogen-based solvents such as methylene chloride, and ketones such as acetone and methyl ethyl ketone are used. It can be used, but is not limited to these. Of course, these cleaning liquids are sufficiently purified and have few impurities. Such a cleaning method can also be applied to the cleaning step in forming the liquid crystal alignment film of the present invention.

In order to enhance the liquid crystal alignment ability of the liquid crystal alignment film of the present invention, annealing treatment with heat or light can be used before and after the heating and firing step, before and after the rubbing step, or before and after irradiation with polarized light or unpolarized light. .. In the annealing treatment, the annealing temperature is 30 to 180 ° C., preferably 50 to 150 ° C., and the time is preferably 1 minute to 2 hours. Further, examples of the annealing light used for the annealing treatment include a UV lamp, a fluorescent lamp, and an LED lamp. The irradiation amount of light is preferably 0.3 to 10 J / cm ^2.

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

The liquid crystal alignment film of the present invention is characterized by having a particularly large orientation anisotropy. The magnitude of such anisotropy can be evaluated by the method using polarized IR described in JP-A-2005-275364 and the like. It can also be evaluated by a method using ellipsometry as shown in the following examples. Specifically, the retardation value of the liquid crystal alignment film can be measured by a spectroscopic ellipsometer. The retardation value of the film increases in proportion to the degree of orientation of the polymer main chain. That is, it is considered that a film having a large retardation value has a large degree of orientation, and when used as a liquid crystal alignment film, an alignment film having a larger anisotropy has a large orientation regulating force with respect to the liquid crystal composition.

The liquid crystal alignment film of the present invention can be suitably used for a transverse electric field type liquid crystal display element. When used in a transverse electric field type liquid crystal display element, the smaller the Pt angle and the higher the liquid crystal alignment ability, the higher the black display level in the dark state and the better the contrast. The Pt angle is preferably 0.1 ° or less.

The liquid crystal alignment film of the present invention can be used for alignment control of optical compensating materials and all other liquid crystal materials, in addition to the orientation application of liquid crystal compositions for liquid crystal displays. Further, since the alignment film of the present invention has a large anisotropy, it can be used alone as an optical compensating material.

The liquid crystal display element of the present invention will be described in detail.
The present invention is formed on a pair of substrates arranged to face each other, electrodes formed on one or both of the facing surfaces of the pair of substrates, and facing surfaces of the pair of substrates. Provided is a liquid crystal display element having the formed liquid crystal alignment film and a liquid crystal layer formed between the pair of substrates, wherein the liquid crystal alignment film is the alignment film of the present invention.

The electrode is not particularly limited as long as it is an electrode formed on one surface of the substrate. Examples of such an electrode include an ITO or a metal vapor deposition film. Further, the electrodes may be formed on the entire surface of one surface of the substrate, or may be formed in a desired shape that is patterned, for example. The desired shape of the electrode includes, for example, a comb shape or a zigzag structure. The electrodes may be formed on one of the pair of substrates, or may be formed on both substrates. The form of electrode formation differs depending on the type of liquid crystal display element. For example, in the case of an IPS type liquid crystal display element, an electrode is arranged on one of the pair of substrates, and in the case of another liquid crystal display element, the pair of substrates. Electrodes are arranged on both sides. The liquid crystal alignment film is formed on the substrate or the electrode.

The liquid crystal layer is formed so that the liquid crystal composition is sandwiched between the pair of substrates on which the surfaces on which the liquid crystal alignment film is formed face each other. In the formation of the liquid crystal layer, spacers such as fine particles and resin sheets that are interposed between the pair of substrates to form an appropriate interval can be used as needed.

The liquid crystal composition is not particularly limited, and various liquid crystal compositions having positive or negative dielectric anisotropy can be used. Preferred liquid crystal compositions having a positive dielectric anisotropy include Japanese Patent Application Laid-Open No. 3086228, Japanese Patent No. 2635435, Japanese Patent Application Laid-Open No. 5-501735, Japanese Patent Application Laid-Open No. 8-157826, Japanese Patent Application Laid-Open No. 8-231960, Japanese Patent Application Laid-Open No. 9-241644 (EP885272A1). Kaihei 9-302346 (EP806466A1), Japanese Patent Application Laid-Open No. 8-199168 (EP722998A1), Japanese Patent Application Laid-Open No. 9-235552, Japanese Patent Application Laid-Open No. 9-255956, Japanese Patent Application Laid-Open No. 9-241643 (EP885271A1), Japanese Patent Application Laid-Open No. 10-204016 (EP844229A1), Japanese Patent Application Laid-Open No. 10-204229A1 Examples thereof include liquid crystal compositions disclosed in −204436, JP-A-10-231482, JP-A-2000-087404, JP-A-2001-48822 and the like.

It is also permissible to add one or more kinds of optically active compounds to the liquid crystal composition having a positive or negative dielectric anisotropy.

ここで、Ｒ^１ａおよびＲ^２ａは独立して、炭素数１〜１２のアルキル、炭素数１〜１２のアルコキシ、炭素数２〜１２のアルケニル、または少なくとも１つの水素がフッ素で置き換えられた炭素数２〜１２のアルケニルであり、環Ａ^２および環Ｂ^２は独立して、１，４−シクロへキシレン、テトラヒドロピラン−２，５−ジイル、１，３−ジオキサン−２，５−ジイル、１，４−フェニレン、２−フルオロ−１，４−フェニレン、２，５−ジフルオロ−１，４−フェニレン、２，３−ジフルオロ−１，４−フェニレン、２−フルオロ−３−クロロ−１，４−フェニレン、２，３−ジフルオロ−６−メチル−１，４−フェニレン、２，６−ナフタレンジイル、または７，８−ジフルオロクロマン−２，６−ジイルであり、ここで、環Ａ^２および環Ｂ^２の少なくとも１つは２，３−ジフルオロ−１，４−フェニレン、２−フルオロ−３−クロロ−１，４−フェニレン、２，３−ジフルオロ−６−メチル−１，４−フェニレン、または７，８−ジフルオロクロマン−２，６−ジイルであり、Ｚ^１は独立して単結合、−（ＣＨ_２）_２−、−ＣＨ_２Ｏ−、−ＣＯＯ−、または−ＣＦ_２Ｏ−であり、ｊは１、２、または３であり、ｊが２または３である時、任意の２つの環Ａ^２は同じであっても異なってもよく、任意の２つのＺ^１は同じであっても異なってもよい。 The liquid crystal composition having a negative dielectric anisotropy will be described. Examples of the liquid crystal composition having a negative dielectric anisotropy include a composition containing at least one liquid crystal compound selected from the group of liquid crystal compounds represented by the following formula (NL-1) as the first component. ..

Here, R ^1a and R ^2a independently have an alkyl having 1 to 12 carbon atoms, an alkoxy having 1 to 12 carbon atoms, an alkenyl having 2 to 12 carbon atoms, or a carbon number in which at least one hydrogen is replaced with fluorine. It is an alkenyl of 2 to 12, and ring A ² and ring B ² are independently 1,4-cyclohexylene, tetrahydropyrane-2,5-diyl, 1,3-dioxane-2,5-diyl, 1 , 4-Phenylene, 2-fluoro-1,4-phenylene, 2,5-difluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2-fluoro-3-chloro-1,4 - phenylene, a 2,3-difluoro-6-methyl-1,4-phenylene, 2,6-naphthalene-diyl or 7,8-difluoro-chroman-2,6-diyl, wherein the ring ^{a 2} and ring At ^{least one of B 2} is 2,3-difluoro-1,4-phenylene, 2-fluoro-3-chloro-1,4-phenylene, 2,3-difluoro-6-methyl-1,4-phenylene, or 7,8-Difluorochroman-2,6-diyl, Z ¹ is independently single-bonded,-(CH ₂ ) _2- , -CH ₂ O-, -COO-, or -CF ₂ O- , j is 1, 2 or 3, when j is 2 or 3, two arbitrary rings a ² may be the same or different, any two of Z ¹ are the same May also be different.

Preferred rings A ² and B ² are 2,3-difluoro-1,4-phenylene or tetrahydropyran-2,5-diyl to increase the dielectric anisotropy, respectively, and 1, to reduce the viscosity 1, 4-Cyclohexylene.

Preferred Z ¹ _{is −CH 2} O− to increase the dielectric anisotropy and a single bond to decrease the viscosity.

The preferred j is 1 for lowering the lower limit temperature and 2 for raising the upper limit temperature.

Specific examples of the liquid crystal compound of the above formula (NL-1) include compounds represented by the following formulas (NL-1-1) to (NL-1-32).

ここで、Ｒ^１aおよびＲ^２ａは独立して、炭素数１〜１２のアルキル、炭素数１〜１２のアルコキシ、炭素数２〜１２のアルケニル、または少なくとも１つの水素がフッ素で置き換えられた炭素数２〜１２のアルケニルであり、環Ａ^２１、環Ａ^２２、環Ａ^２３、環Ｂ^２１、および環Ｂ^２２は独立して、１，４−シクロへキシレンまたは１，４−フェニレンであり、Ｚ^１１およびＺ^１２は、独立して単結合、−（ＣＨ_２）_２−、−ＣＨ_２Ｏ−、または−ＣＯＯ−である。

Here, R ^1a and R ^2a independently have an alkyl having 1 to 12 carbon atoms, an alkoxy having 1 to 12 carbon atoms, an alkenyl having 2 to 12 carbon atoms, or a carbon number in which at least one hydrogen is replaced with fluorine. 2-12 alkenyl, ring A ²¹ , ring A ²² , ring A ²³ , ring B ²¹ and ring B ²² are independently 1,4-cyclohexylene or 1,4-phenylene, Z. ¹¹ and Z ¹² are independently single-bonded, − (CH ₂ ) _2- , −CH ₂ O−, or −COO−.

Preferred R ^1a and R ^2a are alkyl having 1 to 12 carbon atoms to increase stability against ultraviolet rays or heat, or alkoxy having 1 to 12 carbon atoms to increase the absolute value of dielectric anisotropy.

Preferred alkyls are methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, or octyl. More preferred alkyls are ethyl, propyl, butyl, pentyl, or heptyl to reduce the viscosity.

Preferred alkoxys are methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, or heptyloxy. More preferred alkoxys for reducing viscosity are methoxy or ethoxy.

Preferred alkenyls are vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 2-hexenyl, It is 3-hexenyl, 4-hexenyl, or 5-hexenyl. More preferred alkenyl is vinyl, 1-propenyl, 3-butenyl, or 3-pentenyl to reduce viscosity. The preferred configuration of -CH = CH- in these alkenyl depends on the position of the double bond. Trans is preferred for alkenyl such as 1-propenyl, 1-butenyl, 1-pentenyl, 1-hexenyl, 3-pentenyl, 3-hexenyl for reasons such as lowering the viscosity. Sis is preferred for alkenyl such as 2-butenyl, 2-pentenyl, 2-hexenyl. In these alkenyl, linear alkenyl is preferable to branching.

Preferred examples of alkenyl in which at least one hydrogen is replaced with fluorine are 2,2-difluorovinyl, 3,3-difluoro-2-propenyl, 4,4-difluoro-3-butenyl, 5,5-difluoro-4. -Pentenyl, and 6,6-difluoro-5-hexenyl. More preferred examples are 2,2-difluorovinyl and 4,4-difluoro-3-butenyl to reduce the viscosity.

Preferred rings A ²¹ , ring A ²² , ring A ²³ , ring B ²¹ and ring B ²² are each 1,4-cyclohexylene to reduce viscosity.

Preferred Z ¹¹ and Z ¹² _{are −CH 2} O− to increase the dielectric anisotropy and are single bonds to reduce the viscosity.

The compounds (NL-1) in which the liquid crystal composition having a negative dielectric anisotropy is preferable as the first component are compounds (NL-1-1), (NL-1--4), and (NL-1-. 7) or (NL-1-32).

Preferred examples of the liquid crystal composition having a negative permittivity anisotropy are JP-A-57-114532, JP-A-2-4725, JP-A-4-224885, JP-A-8-40953, JP-A-8-104869, and Japanese Patent Application Laid-Open No. 8-104869. Kaihei 10-168076, JP-A-10-168453, JP-A-10-236998, JP-A-10-236990, JP-A-10-236992, JP-A-10-2369999, JP-A-10-236994, JP-A-10-237000, JP-A-10. -237004, Japanese Patent Application Laid-Open No. 10-237024, Japanese Patent Application Laid-Open No. 10-237035, Japanese Patent Application Laid-Open No. 10-237075, Japanese Patent Application Laid-Open No. 10-237076, Japanese Patent Application Laid-Open No. 10-237448 (EP9677261A1) 10-291945, JP-A-11-029581, JP-A-11-080049, JP-A-2000-256307, JP-A-2001-019965, JP-A-2001-072626, JP-A-2001-192657, JP-A-2010-037428, International Publication 2011 / Examples thereof include liquid crystal compositions disclosed in 024666, International Publication 2010/072370, Japanese Patent Application Laid-Open No. 2010-537010, Japanese Patent Application Laid-Open No. 2012-077201, Japanese Patent Application Laid-Open No. 2009-08432.

Further, for example, in the liquid crystal composition used for the device of the present invention, additives may be further added from the viewpoint of improving the orientation, for example. Such additives are photopolymerizable monomers, optically active compounds, antioxidants, UV absorbers, dyes, defoamers, polymerization initiators, polymerization inhibitors and the like.

The most preferable structures of the photopolymerizable monomer or oligomer for the purpose of improving the orientation of the liquid crystal include the structures of the formulas (PM-1-1) to (PM-1-6).

The amount of the photopolymerizable monomer or oligomer is preferably 0.01% by weight or more in order to exhibit the effect of determining the inclination direction of the liquid crystal after polymerization. Further, it is desirable that the content is 30% by weight or less in order to make the orientation effect of the polymer after polymerization appropriate, or to prevent unreacted monomers or oligomers from elution into the liquid crystal after irradiation with ultraviolet rays.

An optically active compound is mixed into the composition for the purpose of inducing a helical structure of the liquid crystal to give a helix angle. Examples of such compounds are from compound (PAC-1-1) to compound (PAC-1--4). The preferred proportion of the optically active compound is 5% by weight or less. A more preferred ratio is in the range of 0.01% by weight to 2% by weight.

Antioxidants are added to the liquid crystal composition to prevent a decrease in resistivity due to heating in the atmosphere, or to maintain a large voltage retention not only at room temperature but also at high temperatures after long-term use of the device. Be mixed.

A preferred example of an antioxidant is a compound (AO-1) in which w is an integer of 1 to 10. In compound (AO-1), the preferred w is 1, 3, 5, 7, or 9. A more preferable w is 1 or 7. Since the compound (AO-1) in which w is 1 is highly volatile, it is effective in preventing a decrease in resistivity due to heating in the atmosphere. Since the compound (AO-1) in which w is 7 has low volatility, it is effective in maintaining a large voltage holding ratio not only at room temperature but also at high temperatures after the device has been used for a long time. The preferable ratio of the antioxidant is 50 ppm or more in order to obtain the effect, and 600 ppm or less so as not to lower the upper limit temperature or raise the lower limit temperature. A more preferred ratio is in the range of 100 ppm to 300 ppm.

Preferred examples of the ultraviolet absorber are benzophenone derivatives, benzoate derivatives, triazole derivatives and the like. Light stabilizers such as sterically hindered amines are also preferred. The preferable ratio of these absorbents and stabilizers is 50 ppm or more in order to obtain the effect, and 10000 ppm or less so as not to lower the upper limit temperature or raise the lower limit temperature. A more preferred ratio is in the range of 100 ppm to 10000 ppm.

Dichroic dyes such as azo dyes, anthraquinone dyes and the like are mixed into the composition to accommodate devices in GH (Guest host) mode. The preferred proportion of dye is in the range of 0.01% by weight to 10% by weight.

To prevent foaming, a defoaming agent such as dimethyl silicone oil or methyl phenyl silicone oil is mixed with the composition. The preferable ratio of the defoaming agent is 1 ppm or more in order to obtain the effect, and 1000 ppm or less in order to prevent defective labeling. A more preferred ratio is in the range of 1 ppm to 500 ppm.

Polymerizable compounds can be mixed into the composition to accommodate devices in PSA (polymer sustained alignment) mode. Preferred examples of the polymerizable compound are compounds having a polymerizable group such as acrylate, methacrylate, vinyl compound, vinyloxy compound, propenyl ether, epoxy compound (oxylane, oxetane) and vinyl ketone. Particularly preferred examples are acrylate or methacrylate derivatives. Examples of such compounds are compound (PM-2-1) to compound (PM-2-9). The preferable ratio of the polymerizable compound is about 0.05% by weight or more in order to obtain the effect, and about 10% by weight or less in order to prevent display defects. A more preferred ratio is in the range of about 0.1% by weight to about 2% by weight.

ここで、Ｒ^３ａ、Ｒ^４ａ、Ｒ^５ａ、およびＲ^６ａは独立して、アクリロイルまたはメタクリロイルであり、Ｒ^７ａおよびＲ^８ａは独立して、水素、ハロゲン、または炭素数１から１０のアルキルであり、Ｚ^１３、Ｚ^１４、Ｚ^１５、およびＺ^１６は独立して、単結合または炭素数１から１２のアルキレンであり、少なくとも１つの−ＣＨ_２−は−Ｏ−または−ＣＨ＝ＣＨ−により置き換えられていてもよく、ｓ、ｔ、およびｕは独立して、０、１、または２である。

Here, R ^3a , R ^4a , R ^5a , and R ^6a are independently acryloyl or methacryloyl, and R ^7a and R ^8a are independently hydrogen, halogen, or alkyl having 1 to 10 carbon atoms. , Z ¹³ , Z ¹⁴ , Z ¹⁵ and Z ¹⁶ are independently single bonds or alkylene with 1 to 12 carbon atoms and at least one -CH ₂ − is replaced by -O- or -CH = CH-. S, t, and u are independently 0, 1, or 2.

A polymerization initiator can be mixed as a substance necessary for easily generating radicals or ions and initiating a chain polymerization reaction. For example, the photopolymerization initiators Irgacure651®, Irgacure184®, or Darocure1173® (Ciba Japan KK) are suitable for radical polymerization. The polymerizable compound preferably contains a photopolymerization initiator in the range of 0.1% by weight to 5% by weight. Particularly preferably, the photopolymerization initiator is contained in the range of 1% by weight to 3% by weight.

In a radical polymerization system, a polymerization inhibitor is mixed for the purpose of rapidly reacting with a radical generated from a polymerization initiator or a monomer to change into a stable radical or a neutral compound, and as a result, stopping the polymerization reaction. Can be done. Polymerization inhibitors are structurally classified into several categories. One is a self-stable radical such as tri-p-nitrophenylmethyl, di-p-fluorophenylamine, etc., and the other is a stable radical that easily reacts with radicals present in the polymerization system. Typical examples are nitro, nitriso, amino, and polyhydroxy compounds. Typical examples of the latter include hydroquinone and dimethoxybenzene. The preferable ratio of the polymerization inhibitor is 5 ppm or more in order to obtain the effect, and 1000 ppm or less in order to prevent display defects. A more preferred ratio is in the range of 5 ppm to 500 ppm.

Hereinafter, the present invention will be described with reference to Examples. The evaluation methods and compounds used in the examples are as follows.

<Evaluation method>
1. 1. Weight average molecular weight (Mw)
The weight average molecular weight of the polyamic acid was measured by the GPC method using a 2695 separation module and a 2414 differential refractometer (manufactured by Waters), and was determined by polystyrene conversion. The obtained polyamic acid was diluted with a phosphoric acid-DMF mixed solution (phosphoric acid / DMF = 0.6 / 100: weight ratio) so that the polyamic acid concentration was about 2% by weight. The column used was HSPgel RT MB-M (manufactured by Waters), and the measurement was carried out under the conditions of a column temperature of 50 ° C. and a flow velocity of 0.40 mL / min using the mixed solution as a developing agent. As the standard polystyrene, TSK standard polystyrene manufactured by Tosoh Corporation was used.

2. Wetting spread by drop test Nichiryo EX Plus II (capacity range: 0.5 to 10 μl) is equipped with Pipette Tips (Volume: 20 μl) manufactured by BioPointe Scientific and filled with 10 μl of liquid crystal alignment agent. This was dropped onto a substrate with ITO, allowed to stand for 240 seconds, and then dried on a 60 ° C. hot plate for 600 seconds. After that, the wet spread of the alignment film was measured with a ruler, and the judgment criteria were set as follows.
Judgment criteria for wet spread by drop test ・ Less than 40 mm ×
・ 40 mm or more and less than 43 mm △
・ 43 mm or more and less than 45 mm 〇 ・ 45 mm or more ◎

3. 3. In-plane unevenness in inkjet printing A liquid crystal alignment agent was applied to a substrate with ITO using an inkjet device EB100XY100 manufactured by Konica Minolta. After application, it was allowed to stand for 180 seconds and dried on a 60 ° C. hot plate for 80 seconds. After that, the presence or absence of in-plane unevenness of the coated substrate was visually confirmed. The specifications of the inkjet device are described below.
Head: KM512MH (Nozzle number: 512 droplets 14pL)
Head temperature: 25 ° C
Applied voltage: 19V
Frequency 709Hz
Resolution 360 dpi
Transport speed 50 mm / sec
Head / glass substrate spacing 28 mm

4. Contrast The contrast of the liquid crystal display element described later was evaluated using a luminance meter (YOKOGAWA 3298F). A liquid crystal display element was placed under a polarizing microscope in a cross Nicol state, and the minimum brightness was measured as black brightness. Next, an arbitrary rectangular wave voltage was applied to the device, and the maximum brightness was measured as white brightness. This white brightness / black brightness value was taken as the contrast. The contrast is judged to be poor when it is less than 2500, good when it is 2500 or more and less than 3000, and best when it is 3000 or more.

5. AC afterimage measurement The brightness-voltage characteristics (BV characteristics) of the liquid crystal display element, which will be described later, were measured. Let this be the luminance-voltage characteristic: B (before) before stress is applied. Next, an alternating current of 4.5 V and 60 Hz was applied to the device for 20 minutes, short-circuited for 1 second, and the luminance-voltage characteristic (BV characteristic) was measured again. Let this be the brightness-voltage characteristic after stress application: B (after). Based on these values, the brightness change rate ΔB (%) is determined.

ΔB (%) = [B (after) -B (before)] / B (before) (Equation AC1)

Estimated using the formula of. These measurements were made with reference to the International Publication No. 2000/43833 pamphlet. It can be said that the smaller the value of ΔB (%) at a voltage of 0.75 V, the more the occurrence of AC afterimage can be suppressed. It was judged to be the best if it was less than.

<Tetracarboxylic dianhydride>

<Diamine>

<Solvent>
NMP: N-methyl-2-pyrrolidone GBL: γ-butyrolactone BC: Butyl cellosolve BP: 1-butoxy-2-propanol EDM: Diethylene glycol ethyl methyl ether EDE: Diethylene glycol diethyl ether BDM: Diethylene glycol butyl methyl ether DIBC: Diisobutylcarbinol 2P: 2-Pentanone 3P: 3-Pentanone 4M2P: 4-Methyl-2-pentanone DIBK: Diisobutylketone MIBC: 4-Methyl-2-pentanol

<Additives>
Add. 1: 1,3-Bis (4,5-dihydro-2-oxazolyl) Benzene Add. 2: 2- (3,4-Epoxycyclohexyl) ethyltrimethoxysilane Add. 3: 3,3', 4,4'-diepoxy bicyclohexyl

<Synthesis of polyamic acid>
[Synthesis Example A-1]
1.4184 g of the compound represented by the formula (V-2-1) in a 200 mL brown four-necked flask equipped with a thermometer, a stirrer, a raw material charging port and a nitrogen gas inlet, formula (DI-5-1). 0.5736 g of the compound represented by (m = 4), 0.1281 g of the compound represented by the formula (DI-13-1) and 44.0 g of the dehydrated NMP were added and dissolved by stirring under a dry nitrogen stream. Then, 3.8799 g of the compound represented by the formula (AN-4-17) (m = 8) and 20.0 g of dehydrated NMP were further added, and stirring was continued at room temperature for 24 hours. BC30.0 g was added to this reaction solution to obtain a polyamic acid solution having a polymer solid content concentration of 6% by weight. Let this polyamic acid solution be (PA-1). The weight average molecular weight of the polyamic acid contained in (PA-1) was 10,300.

[Synthesis Examples A-2 to A-4]
Polyamic acid solutions (PA-2) to (PA-4) having a polymer solid content concentration of 6% by weight according to Synthesis Example A-1, except that the tetracarboxylic dianhydride, diamine, and solvent compositions were changed. Was prepared. The composition of the raw material and the solvent is shown in Table 1 together with (PA-1).

[Synthesis Example B-1]
In a 200 mL brown four-necked flask equipped with a thermometer, a stirrer, a raw material charging port and a nitrogen gas inlet, 1.9123 g of the compound represented by the formula (DI-13-1) and the formula (DI-5-9). ), 0.8561 g of the compound represented by the formula (DI-4-1), 0.3082 g of the compound represented by the formula (DI-4-1), and 44.0 g of the dehydrated NMP were added and dissolved by stirring under a dry nitrogen stream. 1.8354 g of the compound represented by the formula (AN-1-1), 1.0880 g of the compound represented by the formula (AN-3-2), and 20.0 g of the dehydrated NMP were further added, and stirring was continued at room temperature for 24 hours. .. BC30.0 g was added to this reaction solution to obtain a polyamic acid solution having a polymer solid content concentration of 6% by weight. Let this polyamic acid solution be (PB-1). The weight average molecular weight of the polyamic acid contained in (PB-1) was 50,000.

[Synthesis Examples B-2 to B-7]
Polyamic acid solutions (PB-2) to (PB-7) having a polymer solid content concentration of 6% by weight were prepared according to Synthesis Example B-1 except that the solvent composition was changed. The composition of the raw material and the solvent is shown in Table 2 together with (PB-1).

<Polymer blend>
[Synthesis Example C-1]
[A] Polyamic acid solution (PA-1) having a polymer solid content concentration of 6% by weight prepared in Synthesis Example A-1 and [B] Polyamic acid having a polymer solid content concentration of 6% by weight prepared in Synthesis Example B-1. The solution (PB-1) was mixed at [A] / [B] = 3.0 / 7.0 (weight ratio). This mixed solution was further diluted with a solution of NMP / BC to obtain a polyamic acid solution having a polymer solid content concentration of 4.0% by weight (PC-1). At this time, the composition ratio (weight ratio) of the solvent used for dilution is NMP / BC = 23.333 / 10.000.

[Synthesis Examples C-2 to C-35]
A polyamic acid solution composed of one polyamic acid solution selected from [A] polyamic acid solutions (PA-2) to (PA-4) and [B] polyamic acid solutions (PB-1) to (PB-5). , Weight ratio [A] / [B] = 3.0 / 7.0, and further dilute with various solvents so that the polymer solid content concentration becomes 4.0% by weight, and polyamic acid. Solutions (PC-1) to (PC-31) were prepared. As for the polyamic acids (PC-32) to (PC-35), one polyamic acid solution selected from the polyamic acid solutions (PB-6) and (PB-7) has a polymer solid content concentration of 4.0. It was prepared by diluting with various solvents so as to have a weight of% by weight. The composition ratios of the polyamic acid solution and the solvent are shown in Table 3 together with (PC-1).

[Synthesis Example D-1]
In a polyamic acid solution (PC-3) having a polymer solid content concentration of 4.0 parts by weight, 15 parts by weight of the additive (Add.1) was added to 100 parts by weight of the polymer, and 100 parts by weight of the additive (Add.2) was added to the polymer. It was added at a ratio of 10 parts by weight to the part. The obtained polyamic acid solution is designated as (PD-1).

[Synthesis Examples D-2 to D-13]
Polyamic acid solutions (PD-2) to (PD-13) were prepared according to Synthesis Example D-1, except that the polyamic acid solution and additives were changed. The additive and solvent composition is shown in Table 4 together with (PD-1).

[Example 1]
<Wet spread by drop test>
A drop test was carried out by the method described above using a polyamic acid solution (PC-22) having a polymer solid content concentration of 4.0% by weight prepared by blending as a liquid crystal alignment agent. As a result, the wet spread was 45 mm or more.

<In-plane unevenness in inkjet printing>
Further, the polyamic acid solution (PC-22) was inkjet printed by the method described above. As a result, no in-plane unevenness was observed.

[Examples 2 to 20, Comparative Examples 1 to 28]
Wet spread and in-plane unevenness were evaluated by the method according to Example 1 except that the polyamic acid solution used as the liquid crystal alignment agent was changed. The results are shown in Tables 5 and 6 together with Example 1.

As shown in Tables 5 and 6, when a polyamic acid solution containing MIBC or DIBK as a third solvent was subjected to a drop test and inkjet printing, wet spread and in-plane unevenness were improved. Further, even when the additive was added to the polyamic acid solution, no change was observed in the good wettability and spread. On the other hand, the polyamic acid solution containing DIBC, 2P, 3P and 4M2P, which has a structure similar to that of MIBC, did not show any improvement in wet spread.

Although DIBK shows a wet spread equivalent to that of MIBC, it can be added only up to 5% by weight with respect to the polyamic acid solution due to its low solubility, and when it is added in a larger amount, cloudiness and precipitation of solid content occur. On the other hand, MIBC can be added in an amount of 15% by weight or more with respect to the polyamic acid solution, and shows a higher wet spread.

<Presence / absence of flow orientation during cell injection, evaluation of contrast and AC afterimage>
[Example 21]
A polyamic acid solution (PC-22) having a polymer solid content concentration of 4% by weight prepared by blending was used as a liquid crystal alignment agent, and this liquid crystal alignment agent was used as a substrate with SiNx / ITO comb tooth electrodes and a glass substrate with a spacer (spacer height: 4 μm). ) Was coated with an inkjet coating device (Konica Minolta inkjet device EB100XY100). The droplet spacing and the voltage applied to the cartridge were adjusted so that the liquid crystal alignment film had the following film thickness. After coating, it was heated and dried at 70 ° C. for 80 seconds on a hot plate (EC hot plate (EC-1200N) manufactured by AS ONE Corporation). Next, using Multilite ML-501C / B manufactured by Ushio, Inc., the substrate was irradiated with linearly polarized ultraviolet rays from the vertical direction via a polarizing plate. ^{The exposure energy at this time is 1.0 ± 0.1 J / cm 2} at a wavelength of 365 nm when the amount of light is measured using an ultraviolet integrated light meter UIT-150 (receiver UVD-S365) manufactured by Ushio, Inc. The exposure time was adjusted so as to. Subsequently, a liquid crystal alignment film having a film thickness of 100 ± 10 nm was formed by heat treatment at 230 ° C. for 15 minutes in a clean oven (ESPEC CO., LTD., PVHC-231).

<Preparation of FFS cell, confirmation of flow orientation, contrast and AC afterimage measurement>
The planes of the two substrates on which the liquid crystal alignment film is formed face each other, and the orientations of the two substrates are further opposed so that the polarization directions of the ultraviolet rays irradiated to the respective liquid crystal alignment films are parallel. A gap for injecting the liquid crystal composition was formed between the membranes and bonded to each other to assemble an empty FFS cell having a cell thickness of 4 μm. The positive liquid crystal composition 1 was vacuum-injected into the prepared empty FFS cell, and the injection port was sealed with a photocuring agent to prepare an FFS liquid crystal display element. When the orientation of the liquid crystal in the obtained liquid crystal display element was confirmed, no flow orientation was observed. When the contrast value was measured, it was 3010, and when the AC afterimage was measured, ΔB was 1.9%.

Positive liquid crystal composition 1

[Example 22]
Using a polyamic acid solution (PC-22) with a polymer solid content concentration of 4% by weight prepared by blending as a liquid crystal alignment agent, a spinner (Mikasa) was applied to a substrate with SiNx / ITO comb tooth electrodes and a glass substrate with spacers (spacer height: 4 μm). It was applied with a spin coater (1H-DX2) manufactured by Co., Ltd. Including the following examples, the rotation speed of the spinner was adjusted according to the viscosity of the liquid crystal alignment agent so that the alignment film had the following film thickness. After coating, it was heated and dried at 70 ° C. for 80 seconds on a hot plate (EC hot plate (EC-1200N) manufactured by AS ONE Corporation). Next, using Multilite ML-501C / B manufactured by Ushio, Inc., the substrate was irradiated with linearly polarized ultraviolet rays from the vertical direction via a polarizing plate. ^{The exposure energy at this time is 1.0 ± 0.1 J / cm 2} at a wavelength of 365 nm when the amount of light is measured using an ultraviolet integrated light meter UIT-150 (receiver UVD-S365) manufactured by Ushio, Inc. The exposure time was adjusted so as to. Subsequently, heat treatment was performed at 230 ° C. for 15 minutes in a clean oven (ESPEC CO., LTD., PVHC-231) to form an alignment film having a film thickness of 100 ± 10 nm.

<Preparation of FFS cell, confirmation of flow orientation, contrast and AC afterimage measurement> The surfaces of the two substrates on which the alignment film was formed faced each other, and each alignment film was irradiated. An empty FFS cell having a cell thickness of 4 μm was assembled by forming a gap for injecting the liquid crystal composition between the alignment films facing each other so that the polarization directions of the ultraviolet rays were parallel to each other. The positive liquid crystal composition 1 was vacuum-injected into the prepared empty FFS cell, and the injection port was sealed with a photocuring agent to prepare an FFS liquid crystal display element. When the orientation of the liquid crystal in the obtained liquid crystal display element was confirmed, no flow orientation was observed. When the contrast value was measured, it was 3020, and when the AC afterimage was measured, ΔB was 1.9%.

[Example 23]
The FFS liquid crystal display element conforms to the method described in Example 21 except that a polyamic acid solution (PD-10) was used as the liquid crystal alignment agent and the heat treatment after irradiation with ultraviolet rays was performed at 210 ° C. for 30 minutes. Made. When the orientation of the liquid crystal in the obtained liquid crystal display element was confirmed, no flow orientation was observed. When the contrast value was measured, it was 3030, and when the AC afterimage was measured, ΔB was 2.1%.

[Example 24]
The FFS liquid crystal display element conforms to the method described in Example 22 except that a polyamic acid solution (PD-10) was used as the liquid crystal alignment agent and the heat treatment after irradiation with ultraviolet rays was performed at 210 ° C. for 30 minutes. Made. When the orientation of the liquid crystal in the obtained liquid crystal display element was confirmed, no flow orientation was observed. When the contrast value was measured, it was 3000, and when the AC afterimage was measured, ΔB was 2.3%.

[Example 25]
Described in Example 21 except that a polyamic acid solution (PD-11) was used as the liquid crystal alignment agent and the heat treatment after irradiation with ultraviolet rays was performed at 160 ° C. for 20 minutes and then at 230 ° C. for 15 minutes. An FFS liquid crystal display element was manufactured according to the method. When the orientation of the liquid crystal in the obtained liquid crystal display element was confirmed, no flow orientation was observed. When the contrast value was measured, it was 3010, and when the AC afterimage was measured, ΔB was 2.2%.

[Example 26]
Described in Example 22 except that a polyamic acid solution (PD-11) was used as the liquid crystal alignment agent and the heat treatment after irradiation with ultraviolet rays was performed at 160 ° C. for 20 minutes and then at 230 ° C. for 15 minutes. An FFS liquid crystal display element was manufactured according to the method. When the orientation of the liquid crystal in the obtained liquid crystal display element was confirmed, no flow orientation was observed. When the contrast value was measured, it was 3000, and when the AC afterimage was measured, ΔB was 2.3%.

[Example 27]
The description of Example 21 except that a polyamic acid solution (PC-30) was used as the liquid crystal alignment agent and the heat treatment after irradiation with ultraviolet rays was carried out at 180 ° C. for 20 minutes and then at 220 ° C. for 15 minutes. An FFS liquid crystal display element was manufactured according to the method. When the orientation of the liquid crystal in the obtained liquid crystal display element was confirmed, no flow orientation was observed. When the contrast value was measured, it was 3100, and when the AC afterimage was measured, ΔB was 2.1%.

[Example 28]
The description of Example 22 except that a polyamic acid solution (PC-30) was used as the liquid crystal alignment agent and the heat treatment after irradiation with ultraviolet rays was carried out at 180 ° C. for 20 minutes and then at 220 ° C. for 15 minutes. An FFS liquid crystal display element was manufactured according to the method. When the orientation of the liquid crystal in the obtained liquid crystal display element was confirmed, no flow orientation was observed. When the contrast value was measured, it was 3120, and when the AC afterimage was measured, ΔB was 2.2%.

As described above, the same liquid crystal alignment agent is spun as the FFS liquid crystal display element having a liquid crystal alignment film formed by drying, irradiating with ultraviolet rays, and heat-treating a coating film obtained by printing the liquid crystal alignment agent of the present invention on a substrate by an inkjet method. An FFS liquid crystal display element having a liquid crystal alignment film formed by coating by the coating method and similarly drying, irradiating with ultraviolet rays, and heat-treating was compared with the presence or absence of flow orientation, contrast, and AC afterimage. The performance of the photoalignment film obtained from the coating film was comparable to that of the photoalignment film obtained from the coating film obtained by the spin coating method, and showed good cell characteristics.

It was confirmed that the liquid crystal alignment agent of the present invention can form a liquid crystal alignment film having good ejection properties, in-plane unevenness and edge linearity. The liquid crystal alignment agent of the present invention can be suitably applied to a model that requires a narrow frame.

Claims (8)

A liquid crystal alignment agent containing at least one polymer and a solvent selected from the group consisting of polyamic acids and derivatives thereof, wherein the solvent contains 4-methyl-2-pentanol. The liquid crystal alignment agent according to claim 1, wherein the ratio of 4-methyl-2-pentanol in the solvent is 0.1 to 20% by weight. The solvent contains at least one selected from the group consisting of N-methyl-2-pyrrolidone, γ-butyrolactone, 1,3-dimethyl-2-imidazolidinone, and N-ethyl-2-pyrrolidone as a good solvent. The liquid crystal alignment agent according to claim 1 or 2. Claims 1 to 3 contain, as a poor solvent, at least one selected from the group consisting of butyl cellosolve, 1-butoxy-2-propanol, diethylene glycol diethyl ether, diethylene glycol ethyl methyl ether, and diethylene glycol butyl methyl ether. The liquid crystal aligning agent according to any one item. The liquid crystal according to any one of claims 1 to 4, wherein the ratio of the good solvent in the solvent is 20 to 89% by weight, and the ratio of the poor solvent is 10 to 60% by weight with respect to the total solvent weight. Orientation agent. A method for forming a liquid crystal alignment film, which comprises a step of applying the liquid crystal alignment agent according to any one of claims 1 to 5 to a substrate by an inkjet method. A method for forming a liquid crystal alignment film, which comprises a step of applying the liquid crystal alignment agent according to any one of claims 1 to 5 to a substrate to form a coating film, and a step of irradiating the coating film with ultraviolet rays. A pair of substrates arranged to face each other, a group of electrodes formed on one or both of the facing surfaces of the pair of substrates, a plurality of active elements connected to the group of electrodes, and the pair of active elements. In a method for manufacturing a liquid crystal display element having a liquid crystal alignment film formed on facing surfaces of each substrate and a liquid crystal layer formed between the pair of substrates.
A method for manufacturing a liquid crystal display element, wherein the liquid crystal alignment film is formed by the method according to claim 6 or 7.