KR20110055384A - Liquid crystal aligning agent, liquid crystal alignment layer and liquid crystal display - Google Patents

Abstract

PURPOSE: A liquid crystal aligning agent and a liquid crystal alignment layer are provided to obtain a liquid crystal display with high voltage holding rate, excellent heat reliability and light resistance. CONSTITUTION: A liquid crystal aligning agent contains a polymer component A as an essential ingredient and a polymer component B as an arbitrary component. The polymer component A is polyamic acids or derivatives obtained by reacting tetracarboxylic dianhydride with a diamine mixture including at least one diamine represented by chemical formula (1) and the other diamines. The polymer component B is polyamic acids or derivatives obtained by reacting tetracarboxylic dianhydride with at least one of the other diamines.

Description

Liquid crystal aligning agent, liquid crystal aligning film, and liquid crystal display element {LIQUID CRYSTAL ALIGNING AGENT, LIQUID CRYSTAL ALIGNMENT LAYER AND LIQUID CRYSTAL DISPLAY}

This invention relates to the liquid crystal aligning agent containing the polyamic acid obtained by making the diamine which has a triazine structure react with tetracarboxylic dianhydride, and its use.

The driving method of the liquid crystal display device is twisted nematic (TN) mode, super twisted nematic (STN) mode, in plane switching (IPS) mode, and vertical alignment (Vertical alignment). : Can be classified into VA) mode.

An external light source is required for the operation of these liquid crystal display elements, but depending on the type of the external light source, it is roughly classified into two types of "transmission type" and "reflection type". The transmissive type is a liquid crystal of a type which displays using the backlight on the back of the screen as a light source. On the other hand, the reflection type is a type which displays by reflection of external light. In particular, in a transmissive liquid crystal display element, the liquid crystal aligning film is always exposed to backlight light during operation, and the temperature rise of the liquid crystal display element itself by backlight light irradiation is considered. On the other hand, in the reflection type liquid crystal, sunlight can be assumed as a light source when used outdoors. Since sunlight contains ultraviolet light, it becomes a factor of deterioration of a liquid crystal aligning film (for example, refer patent documents 1-3).

Moreover, especially in the manufacturing process of a large size liquid crystal display element, the liquid crystal dropping method (ODF method; One Drop Fill method) may be used for a liquid crystal injection process for the purpose of a yield improvement. In the liquid crystal dropping method, an ultraviolet light curing type is usually used as a sealing agent. That is, in a liquid crystal dropping method, since a liquid crystal aligning film is exposed to ultraviolet light, development of the liquid crystal aligning film with favorable UV tolerance is calculated | required (for example, refer patent document 4).

Thus, in recent years, liquid crystal display elements have been processed under severe conditions or have been used in harsh environments. Therefore, as one of the characteristics required for the liquid crystal aligning agent, electrical characteristics such as voltage retention after exposure to light and heat or after being driven for a long time in such an environment have become important.

[Patent Document 1] Japanese Patent Application Publication No. 2008-70463 [Patent Document 2] Japanese Patent Application Publication No. 2006-292940 [Patent Document 3] Japanese Patent Application Publication No. 2002-333624 [Patent Document 4] Japanese Patent Application Publication No. 2001-174829

An object of the present invention is, for example, to solve the above problem and to provide a liquid crystal aligning agent for a liquid crystal display device having excellent reliability. Moreover, the subject of this invention is providing the liquid crystal display element provided with the liquid crystal aligning film formed using the said liquid crystal aligning agent.

MEANS TO SOLVE THE PROBLEM The present inventors earnestly research in order to solve the said subject, and when the polyamic acid obtained by making a 2, 4- diamino- 1,3, 5- triazine derivative react with tetracarboxylic dianhydride is used for a liquid crystal aligning film, In the liquid crystal display element which has a liquid crystal aligning film, it discovered that the voltage retention is high and the effect that heat reliability and light resistance become favorable is acquired.

The liquid crystal aligning agent of this invention can be shown by following [1] term.

[1] A polyamic acid or derivative thereof obtained by reacting a diamine mixture composed of at least one of diamines represented by formula (1) with at least one of other diamines with tetracarboxylic dianhydride is called polymer component A;

When the polyamic acid obtained by reacting at least one other diamine with tetracarboxylic dianhydride, or its derivative is called polymer component B;

The liquid crystal aligning agent containing polymer component A as an essential component, and containing polymer component B as an arbitrary component.

In formula (1), R ¹ is hydrogen, -OH, -NH-C ₄ H ₉ , -N (CH ₃ ) ₂ , -N (C ₂ H ₅ ) ₂ , -N (CH ₂ CH = CH ₂ ) ₂ , -NH-CH ₂ CH = CH ₂ , halogen, alkyl of 1 to 20 carbon atoms, alkoxy of 1 to 20 carbon atoms, alkenyl of 2 to 20 carbon atoms, aryl of 6 to 20 carbon atoms, aryl of 7 to 20 carbon atoms Alkyl or the following structure.

According to the present invention, it is possible to provide a liquid crystal display device having excellent high voltage retention, thermal reliability, and light resistance, a liquid crystal alignment film for the same, a polymer capable of forming the liquid crystal alignment film, and a liquid crystal alignment agent.

Usage of the terms in this specification is as follows.

A "liquid crystalline compound" is a generic term for a compound having a liquid crystal phase and a compound which does not have a liquid crystal phase but is useful as a component of the liquid crystal composition. A liquid crystal compound, a liquid crystal composition, and a liquid crystal display element may be described with a compound, a composition, and an element, respectively.

The diamine represented by Formula (1) may be described as diamine (1). Similarly, the diamine represented by another formula may be abbreviated.

Tetracarboxylic dianhydride may be abbreviated as acid anhydride. And tetracarboxylic dianhydride represented by Formula (T1) may be described as acid anhydride (T1). The same applies to tetracarboxylic dianhydride represented by another formula.

The symbol which enclosed the letter (for example, A) with a hexagon in a chemical structural formula shows that it is a ring (ring A).

Substituent whose bond position with carbon which comprises a ring is not clear means that the bond position is free within the range which is not chemically trouble-free.

The term "arbitrary" used in the definition of a chemical formula means "a thing which can be selected freely not only in position but also in number." For example, the expression "any A may be substituted with B, C, D or E" means that one A may be substituted with B, C, D or E, and any of a plurality of A's. In addition to the meaning that it may be substituted with any one of B, C, D and E, at least two of A substituted with B, A substituted with C, A substituted with D, and A substituted with E may be mixed. It also has the meaning. When any -CH ₂ -may be substituted with -O-, substitutions such as the occurrence of the bonding group -OO- as a result are not included.

When the same symbol is used in a plurality of expressions, it means that the group has the same definition range, but it does not mean that the same group must be the same in all expressions. In such a case, the same group may be selected in a some formula, and a different group may be selected for every formula.

The present invention consists of the above-mentioned [1] and the following [2] to [9].

[2] The liquid crystal aligning agent according to [1], wherein R ¹ is vinyl or phenyl.

[3] The liquid crystal aligning agent according to [1] or [2], wherein the tetracarboxylic dianhydride is at least one of the compounds represented by formulas (T1) to (T8).

[4] The liquid crystal aligning agent according to [3], wherein the tetracarboxylic dianhydride is at least one of the compounds represented by the formula (T1), the formula (T6) and the formula (T7).

[5] The liquid crystal aligning agent according to any one of [1] to [4], wherein other diamine is diamine selected from the group of compounds represented by formulas (3) to (6):

In the formula (3), Y is alkylene of 1 to 7 carbon atoms, and any -CH ₂ in the alkylene-being optionally substituted by -O- or -S-; R ² is independently alkyl having 1 to 3 carbons; k is independently 0 or 1;

In formula (4), X ¹ is independently -CH ₂ -or -O-; X ² is alkylene having 1 to 8 carbon atoms, and any hydrogen of this alkylene may be substituted with methyl or -CF ₃ ;

In formula (5), X <^1> is independently C1-C6 alkylene or -O-; X ³ is a single bond or alkylene having 1 to 3 carbon atoms, ring T is 1,4-phenylene or 1,4-cyclohexylene, and h is 0 or 1; R ³ is hydrogen or alkyl having 1 to 30 carbon atoms, and optionally -CH ₂ -of the alkyl may be substituted with -O-, -CH = CH- or -C≡C- when the carbon number is 2 to 30; ;

In formula (6), A ¹ is a single bond, -O-, -COO-, -OCO-, -CO-, -CONH-, -NHCO-, alkylene having 1 to 4 carbon atoms or 1,4-cyclo Hexylene; R ⁴ is a group having a steroid skeleton or a group represented by formula (A);

In formula (A), A ² and A ³ are independently a single bond, —O—, —COO—, —OCO—, —CONH—, —NHCO—, —CH═CH— or alkyl having 1 to 12 carbon atoms. Ren;

R ⁵ and R ⁶ are independently fluorine or methyl, f and g are independently an integer of 0 to 2;

Ring S is 1,4-phenylene, 1,4-cyclohexylene, 1,3-dioxane-2,5-diyl, pyrimidine-2,5-diyl, pyridine-2,5-diyl, naphthalene- 1,4-diyl, naphthalene-1,5-diyl, naphthalene-2,6-diyl, naphthalene-2,7-diyl, or anthracene-9,10-diyl;

R ⁷ is H, F, -OH, fluorinated alkyl, alkyl of 1 to 30 carbon atoms, 1 to 30 carbon atoms alkoxy of 1 to 30 carbon _{atoms, -CN, -OCH 2 F, -OCHF} 2 or -OCF _3, and;

c, d and e are independently integers of 0 to 3, wherein c + d + e ≧ 1; When e is 2 or 3, some ring S may all be the same ring, and may consist of at least 2 different ring.

[6] A diamine mixture composed of at least one of diamines represented by formula (1) and at least one of other diamines, wherein a content ratio of diamine represented by formula (1) is 5 to 30 mol relative to the total amount of the diamine mixture. The liquid crystal aligning agent in any one of [1]-[5] which is%.

[7] [1] containing only polymer component A which is a polyamic acid or derivative thereof obtained by reacting a diamine mixture composed of at least one of diamines represented by formula (1) with at least one of other diamines with tetracarboxylic dianhydride The liquid crystal aligning agent in any one of-[6].

[8] A liquid crystal aligning film obtained from the liquid crystal aligning agent according to any one of [1] to [7].

[9] A liquid crystal display device comprising the liquid crystal alignment film according to [8].

Polymer component A which is an essential component of the liquid crystal aligning agent of this invention is a polyamic acid obtained by making the diamine mixture which consists of one or more of diamine (1) and one or more of other diamines react with an acid anhydride, or its derivative (s).

In formula (1), R ¹ is hydrogen, -OH, -NH-C ₄ H ₉ , -N (CH ₃ ) ₂ , -N (C ₂ H ₅ ) ₂ , -N (CH ₂ CH = CH ₂ ) ₂ , -NH-CH ₂ CH = CH ₂ , halogen, alkyl of 1 to 20 carbon atoms, alkoxy of 1 to 20 carbon atoms, alkenyl of 2 to 20 carbon atoms, aryl of 6 to 20 carbon atoms, aryl of 7 to 20 carbon atoms Alkyl or the following structure.

On the other hand, examples of derivatives of this polyamic acid are soluble polyimide, polyamic acid ester and polyamic acid amide. More specifically, 1) polyimide, 2) partially imidized polyamic acid, 3) polyamic acid ester, 4) tetracarboxylic acid dianhydride polyamic acid-polyamide air obtained by substituting a part of dicarboxylic acid (derivative) for reaction And polyamideimide obtained by dehydrating and ring-closing the polyamic acid-polyamide copolymer. In the following description except for the examples, unless otherwise specified, "polyamic acid" is used as a generic term for polyamic acid and its derivatives.

An example of the diamine (1) is shown next.

Among them, diamine (1-1) to diamine (1-3), diamine (1-7), diamine (1-9), diamine (1-13), diamine (1-20) and diamine (1-21). ) Are preferable, and diamine (1-7), diamine (1-9), diamine (1-13) and diamine (1-20) are more preferable. Diamine (1) may be used independently and may use 2 or more together. Moreover, you may mix and use one or more of diamine (1) and one or more of other diamines other than the diamine (1).

It is preferable that other diamine is a diamine selected from the group of the diamine represented by Formula (3)-Formula (6).

In the formula (3), Y is alkylene of 1 to 7 carbon atoms, and any -CH ₂ in the alkylene-is or may be substituted by -O- or -S-. R ² is independently alkyl having 1 to 3 carbons, and k is independently 0 or 1. And as for the coupling | bonding position of an amino group with respect to a benzene ring, a meta position or a para position is preferable with respect to Y, and a para position is more preferable.

Wherein X ¹ is independently —CH ₂ — or —O—; X ² is an alkylene group having 1 to 8 carbon atoms, and any hydrogen in the alkylene it may be substituted with methyl or -CF _3. It is preferable that two X <^1> is the same bonding group. As for the coupling | bonding position of an amino group with respect to a benzene ring, a meta position or a para position is preferable with respect to X <^1> , and a para position is more preferable.

Wherein X ¹ is independently alkylene having 1 to 6 carbon atoms or —O—; X ³ is a single bond or alkylene having 1 to 3 carbon atoms, ring T is 1,4-phenylene or 1,4-cyclohexylene, and h is 0 or 1; R ³ is hydrogen or alkyl having 1 to 30 carbon atoms, and optionally -CH ₂ -of the alkyl may be substituted with -O-, -CH = CH- or -C≡C- when the carbon number is 2 to 30. . The preferable range of this carbon number is 1-10. And as for the coupling | bonding position of an amino group with respect to a benzene ring, a meta position or a para position is preferable with respect to X <^1> , and a para position is more preferable.

Wherein A ¹ is a single bond, —O—, —COO—, —OCO—, —CO—, —CONH—, —NHCO—, alkylene having 1 to 4 carbon atoms or 1,4-cyclohexylene; R ⁴ is a group having a steroid skeleton or a group represented by formula (A).

Wherein A ² and A ³ are independently a single bond, —O—, —COO—, —OCO—, —CONH—, —NHCO—, —CH═CH— or alkylene having 1 to 12 carbon atoms; R ⁵ and R ⁶ are independently fluorine or methyl, and f and g are independently integers of 0 to 2. Ring S is 1,4-phenylene, 1,4-cyclohexylene, 1,3-dioxane-2,5-diyl, pyrimidine-2,5-diyl, pyridine-2,5-diyl, naphthalene- 1,4-diyl, naphthalene-1,5-diyl, naphthalene-2,6-diyl, naphthalene-2,7-diyl, or anthracene-9,10-diyl. R ⁷ is H, F, -OH, _{alkoxy, -CN, -OCH 2 F, -OCHF} 2 or -OCF of fluorinated alkyl, of 1 to 30 carbon atoms in the alkyl, of 1 to 30 carbon atoms having a carbon number of 1 to 30 _3, and therefore The preferable carbon number of alkyl, fluorinated alkyl, and alkoxy is 1-10. c, d, and e are integers of 0-3 independently, and c + d + e≥1. When e is 2 or 3, some ring S may all be the same ring, and may consist of at least 2 different ring. And it is preferable that the bonding position of two amino groups with respect to a benzene ring is a meta position with respect to A <^1> .

Preferable specific examples of the diamine (3) are as follows.

Among these preferred embodiments, diamine (3-1) to diamine (3-4), diamine (3-6), diamine (3-8), diamine (3-13), diamine (3-14), diamine ( 3-19), diamine (3-20) and diamine (3-21) are more preferred.

Preferable specific examples of the diamine (4) are as follows.

Among these preferable specific examples, diamine (4-1) and diamines (4-5) to diamines (4-9) are more preferable.

Preferable specific examples of the diamine (5) are as follows.

Among the preferred specific examples of these diamines (5), diamines (5-3) to diamines (5-8), diamines (5-15) to diamines (5-18), diamines (5-23) and diamines (5-) 24) is more preferable.

Preferred examples of the diamine (6) are as follows.

In these formulas, R ⁸ is alkyl having 3 to 12 carbon atoms or alkoxy having 3 to 12 carbon atoms, preferably alkyl having 5 to 12 carbon atoms or alkoxy having 5 to 12 carbon atoms. R ⁹ is alkyl having 1 to 10 carbon atoms or alkoxy having 1 to 10 carbon atoms, preferably alkyl having 3 to 10 carbon atoms or alkoxy having 3 to 10 carbon atoms.

In these formulas, R ¹⁰ is alkyl having 4 to 16 carbon atoms, preferably alkyl having 6 to 16 carbon atoms. R ¹¹ is alkyl having 6 to 20 carbon atoms, preferably alkyl having 8 to 20 carbon atoms.

In formulas (6-18) to (6-38), R ¹² is alkyl having 1 to ¹² carbons or alkoxy having 1 to 12 carbons, preferably alkyl having 3 to 12 carbons or alkoxy having 3 to 12 carbons. to be. R ¹³ is hydrogen, fluorine, alkyl having 1 to 12 carbon atoms, having 1 to 12 carbon atoms, cyano, and -OCH ₂ F, -OCHF ₂ or -OCF ₃ of a, preferably alkyl having a carbon number of 3 to 12 carbon atoms or a 3 It is -12 alkoxy. A ⁹ is alkylene having 1 to 12 carbon atoms.

In a preferable example of the said diamine (6), diamine (6-1)-diamine (6-11) are more preferable, diamine (6-2), diamine (6-4), diamine (6-5), and diamine. (6-6) is more preferable.

In this invention, other diamine other than diamine (3) -diamine (6) can be used further. Examples of such other diamines are siloxane diamines represented by the formula (7).

Wherein R ²² and R ²³ independently represent alkyl or phenyl having 1 to 3 carbon atoms, R ²¹ independently represent methylene, phenylene or alkyl substituted phenylene, and x independently represent an integer of 1 to 6 and y represents the integer of 1-10.

The other diamine used in this invention can be determined according to the required characteristic of the electric field system in a liquid crystal display element. In the electric field system represented by the TN system or the VA system, a relatively large pretilt angle is required, and therefore, diamine 5 and diamine 6 are mainly used. Moreover, in order to control a pretilt angle, diamine 3 and diamine 4 can also be used. Moreover, in a transverse electric field system, since the pretilt angle is small and high liquid crystal alignability is needed, the diamine 3 and the diamine 4 are mainly used. The use of such diamine is preferable also from a viewpoint of improving the black display characteristic at the time of no voltage application in the liquid crystal display element of a transverse electric field system.

In the above-mentioned diamine mixture used by this invention, it is preferable that the use ratio of the diamine (1) is 5-30 mol% with respect to this diamine mixture whole quantity. The content of the diamine (1) is preferably 5 mol% or more in order to obtain the above-described improvement effect on the electrical properties, that is, thermal reliability and light resistance improvement effect, and is 30 mol% or less in order not to interfere with the synthesis of the polyamic acid. It is preferable.

In addition, in the VA system, the TN system, and the OCB system which are the electric field systems, the expression of a relatively large pretilt angle is essential. In this case, it is necessary to use together at least one of diamine (5) and diamine (6) which are diamine which has a side chain together with diamine (1). By controlling the kind and ratio of these diamines, a predetermined pretilt angle can be expressed. When using these diamines together and obtaining a polymer, the liquid crystal display element to which this polymer was applied can be set as the liquid crystal display element of the electric field system which further improved the voltage retention.

As the acid anhydride to be reacted with diamine, any of aromatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride and aliphatic tetracarboxylic dianhydride can be used as long as the effects of the present invention are not impaired. One or two or more can be selected and used from.

Examples of acid anhydrides that can be used in the present invention are shown below.

More preferable acid anhydride is shown next in the above examples.

Among said acid anhydrides (T1) to acid anhydride (T8), acid anhydride (T1), acid anhydride (T6) and acid anhydride (T7) are more preferable.

The molecular weight of the polyamic acid obtained by the reaction of the diamine and acid anhydride described above is, for example, the weight average molecular weight (Mw) in terms of polystyrene by gel permeation chromatography (GPC), preferably 10,000 to 500,000, and more. Preferably it is 20,000-200,000.

Polyamic acid can be manufactured by the same method as the well-known polyamic acid used for formation of the film | membrane of a polyimide except using the diamine and acid anhydride mentioned above. For example, in the reaction vessel provided with a raw material inlet, a nitrogen inlet, a thermometer, a stirrer and a condenser, at least one of the diamines or at least one of the diamines 1 and the diamines 3 to diamines 6 Mixtures with at least one of the other diamines selected from the group of, optionally in addition to these diamines, at least one of the other diamines other than the diamines (3) to Input. Next, at least one of a solvent (for example, N-methyl-2-pyrrolidone, dimethylformamide, etc.), an amide polar solvent, and an acid anhydride, and a carboxylic acid anhydride are added as necessary, followed by heating under stirring. React. At this time, it is preferable that the total amount of acid anhydride is set to a mole (molar ratio of 0.9 to 1.1) which is approximately equal to the total mole number of the diamine.

The polyamic acid thus obtained includes a chemical structure produced by the reaction of diamine (1) with an acid anhydride, and a chemical structure produced by the reaction of other diamines with acid anhydride. As a chemical structure by reaction of the diamine (1) and an acid anhydride, the structural unit represented by following formula (10) and formula (11) is mentioned, for example. As a structure by reaction of another diamine and an acid anhydride, the structural unit represented by following formula (12) and formula (13) is mentioned, for example. In Formulas 10 to 13, Q ¹ is a residue of an acid anhydride, R ¹ is the same as R ¹ in formula (1), and Q ² is a residue of another diamine.

The structure of Formula 10-Formula 13 can be specified by IR and NMR. More specifically, the polyamic acid in the present invention can be identified by precipitating with a large amount of poor solvent, completely separating the solid and the solvent by filtration and the like, and analyzing by IR and NMR. In addition, the monomer used can be identified by decomposing | dissolving a polyamic acid of solid content with strong alkaline aqueous solutions, such as KOH and NaOH, and extracting with an organic solvent and analyzing by GC, HPLC, or GC-MS.

In addition to the polymer component A, the liquid crystal aligning agent of this invention may further contain the polymer component B which is polyamic acid obtained by reaction of other diamine other than diamine (1), and an acid anhydride. This is in the form of so-called polymer blends. When blending polymer component B, its preferable content is 1-50 weight% with respect to the polymer total amount in a liquid crystal aligning agent, More preferably, it is 2-30 weight%. By setting it as such a range, both the expression of the effect of this invention, and adjustment of the orientation can be aimed at.

In addition to the polyamic acid mentioned above, the liquid crystal aligning agent of this invention may further contain one or two or more of other components. For example, the liquid crystal aligning agent of this invention may contain the epoxy compound further from a viewpoint of improving the durability in a liquid crystal aligning film.

Although content of the said epoxy compound in a liquid crystal aligning agent in this invention is not specifically limited, When using an epoxy compound, it is the rubbing process in the liquid crystal aligning film formed from the liquid crystal aligning agent that it is 0.1-40 weight% in the liquid crystal aligning agent whole quantity. It is preferable from a viewpoint of making durability, such as a film | membrane hard to be scraped, favorable, and it is more preferable that it is 0.2-30 weight%.

As said epoxy compound, For example, a bisphenol-A epoxy resin, a glycidyl ester-type epoxy resin, an alicyclic epoxy resin, the polymer of the monomer which has an oxysilane, and the copolymer of the monomer which has an oxysilane, and another monomer, a following formula The compound represented by (E1)-a formula (E3), (E5), and the compound represented by a formula (E4) are mentioned.

(N in Formula (E4) represents the integer of 0-10.)

As an example of an epoxy resin, epicoat 807, epicoat 815, epicoat 825, epicoat 827 is mentioned. As a compound represented by Formula (E4), Epicoat 828, Epicoat 190P, Epicoat 191P, Epicoat 1004, Epicoat 1256, Araldite CY177, etc. are mentioned. Epicoat is a trade name of Japan Epoxy Resin Co., Ltd. (currently available as a product of the jER series of Mitsubishi Chemical Co., Ltd.). Araldite is a trade name of Nihon Chiba Kaigi (currently available from Hanzman, Japan).

Araldite CY184 is mentioned as a compound represented by Formula (E1). As a compound represented by Formula (E2), the brand names "Ceroxide 2021P" and "EHPE-3150" of Daicel Chemical Co., Ltd. are mentioned. As a compound represented by Formula (E3), the Mitsui Chemicals brand name "Techmore VG3101L" is mentioned. As a compound represented by Formula (E5), the brand name "4, 4- methylene bis (N, N- diglycidyl acetyl)" of Sigma-Aldrich Corporation is mentioned.

Among these, Epicoat 828 which is a compound represented by Formula (E4) (a mixture of compounds of n = 0-4), Araldite CY184 which is a compound represented by Formula (E1), and a compound represented by Formula (E2) are Ceroxide 2021P, Techmore VG3101L which is a compound represented by Formula (E3), and 4,4-methylenebis (N, N- diglycidyl aniline) which is a compound represented by Formula (E5) are in a liquid crystal aligning film It is preferable from a viewpoint of making transparency and flatness favorable.

The liquid crystal aligning agent of this invention may further contain 1 type, or 2 or more types of coupling agents, such as a silane coupling agent, a titanium coupling agent, and an aminosilicon compound, from a viewpoint of improving adhesiveness with respect to a board | substrate. Examples of the aminosilicone compounds include vinyltrimethoxysilane, vinyltriethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, and N- (2-aminoethyl) -3-aminopropylmethyltri Methoxysilane, paraaminophenyltrimethoxysilane, paraaminophenyltriethoxysilane, metaaminophenyltrimethoxysilane, metaaminophenyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltri Ethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-chloropropylmethyldimethoxy Silane, 3-chloropropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, N- (1,3-dimethylbutylidene) -3- (trie Methoxysilyl) -1-propylamine, N, N'-bis [3- (trimethoxysilyl) propyl] ethylenediamine, etc. are mentioned. . And when using this coupling agent, it is preferable that the content rate is 0.01-20 weight% in a liquid crystal aligning agent.

The liquid crystal aligning agent of this invention may further contain other polymer components, such as polyester, an acrylic acid polymer, and an acrylate polymer, in the range which does not impair the characteristic of this invention. As another polymer component, the polyamide and polyamideimide which use the other diamine mentioned above as a diamine raw material can also be used. At this time, the preferable use ratio of another polymer component is 0.2 or less in weight ratio with respect to the above-mentioned polyamic acid which has a residue of diamine (1) in a structural unit.

The liquid crystal aligning agent of this invention may contain surfactant according to the objective from the standpoint of improving the applicability | paintability of a liquid crystal aligning agent, and is an antistatic agent from a viewpoint of improving the antistatic property of a liquid crystal aligning agent. It may further contain.

And the liquid crystal aligning agent of this invention may contain the solvent further from a viewpoint of adjusting the coating property of a liquid crystal aligning agent, and the density | concentration of a polymer component. What is necessary is just to determine the selection conditions of this solvent in consideration of the dissolving power, economical efficiency, environmental safety, etc. with respect to a polymer component, Specifically, the solvent normally used by the manufacturing process of a polymer component, such as a polyamic acid and a soluble polyimide, and a use, are used. You can choose. This solvent may be used singly or two or more mixed solvents may be used.

Examples of the aprotic polar organic solvent that is a solvent for polyamic acid include N-methyl-2-pyrrolidone, dimethylimidazolidinone, N-methylcaprolactam, N-methylpropionamide, N, N-dimethyl Acetamide, dimethyl sulfoxide, N, N-dimethylformamide, N, N-diethylformamide, diethylacetamide, and lactones such as γ-butyrolactone.

Examples of solvents other than aprotic polar organic solvents for the purpose of improving coating properties include alkyl lactate, 3-methyl-3-methoxybutanol, tetralin, isophorone, and ethylene glycol monoalkyl ethers (e.g., Ethylene glycol monobutyl ether), diethylene glycol monoalkyl ether (eg diethylene glycol monoethyl ether), triethylene glycol monoalkyl ether, propylene glycol monoalkyl ether (eg propylene glycol monobutyl ether), malonic acid dialkyl (Eg diethyl maronic acid), dipropylene glycol monoalkyl ethers (eg dipropylene glycol monomethyl ether), and ester compounds of these glycol monoalkyl ethers (eg acetate).

Preferred solvents among them are N-methyl-2-pyrrolidone, dimethylimidazolidinone, γ-butyrolactone, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, propylene glycol monobutyl ether and dipropylene glycol Monomethyl ether.

In this invention, the preferable density | concentration of the polymer component in a liquid crystal aligning agent is 0.1-40 weight%. When apply | coating this liquid crystal aligning agent to a board | substrate, the operation which dilutes the polymer component contained with the solvent in advance may be needed for film thickness adjustment. When the concentration of the polymer component is 40% by weight or less, the diluting solvent can be easily mixed, and it may be considered that it does not interfere with the viscosity adjustment for the film thickness adjustment.

The density | concentration of the polymer component in a liquid crystal aligning agent may be adjusted with the coating method of a liquid crystal aligning agent. When the coating method of a liquid crystal aligning agent is a spinner method or the printing method, in order to maintain film thickness favorably, the density | concentration of the said polymer component is usually made into 10 weight% or less in many cases. In other coating methods, for example, the dipping method or the inkjet method, the concentration may be lower. On the other hand, when the density | concentration of the said polymer component is 0.1 weight% or more, the film thickness of the liquid crystal aligning film obtained will become easy to be optimal. Therefore, the density | concentration of the said polymer component is 0.1 weight% or more, Preferably it is 0.5-10 weight% in normal spinner method, printing method, etc. However, depending on the coating method of a liquid crystal aligning agent, you may use with thinner density | concentration.

On the other hand, when using for manufacture of a liquid crystal aligning film, the viscosity of the liquid crystal aligning agent of this invention can be determined according to the means or method of forming the film of this liquid crystal aligning agent. For example, when forming the film of a liquid crystal aligning agent using a printing machine, it is preferable that it is 5 mPa * s or more from a viewpoint of obtaining sufficient film thickness, and it is preferable that it is 100 mPa * s or less from a viewpoint of suppressing printing nonuniformity, Preferably it is 10-80 mPa * s. When apply | coating a liquid crystal aligning agent and forming a film | membrane of a liquid crystal aligning agent by spin coating, it is preferable that it is 5-200 mPa * s from a similar viewpoint, More preferably, it is 10-100 mPa * s. The viscosity of a liquid crystal aligning agent can be made small by the curing with dilution and stirring with a solvent.

The liquid crystal aligning film of this invention is obtained from the liquid crystal aligning agent of this invention mentioned above. The liquid crystal aligning film of this invention can be obtained according to the conventional method of manufacturing a liquid crystal aligning film from a liquid crystal aligning agent, For example, the liquid crystal aligning film of this invention is a process of forming the coating film of the liquid crystal aligning agent of this invention, and this It can obtain by the process of heating and baking. This coating film can be formed by apply | coating the liquid crystal aligning agent of this invention to the board | substrate in a liquid crystal display element similarly to manufacture of a normal liquid crystal aligning film. As a method of application | coating, generally known methods, such as a spinner method, the printing method, the dipping method, the dropping method, the inkjet method, are applicable. As a board | substrate, the board | substrate which consists of glass in which electrodes, such as an ITO (Indium Tin Oxide) electrode, a color filter, etc. may be provided is mentioned.

The coating film is baked under conditions necessary for dehydration and ring closure of the polyamic acid. As a baking method, the method of heat processing in oven or infrared furnace, the method of heat processing on a hotplate, etc. are applicable. Generally, it is preferable to carry out for 1 minute-3 hours at the temperature of about 150-300 degreeC.

About the liquid crystal aligning film of this invention, you may rub the film obtained by the said baking process as needed. This rubbing process can be performed similarly to the rubbing process for orientation processing of a normal liquid crystal aligning film, and should just be a condition which can obtain sufficient retardation in the liquid crystal aligning film of this invention. Particularly preferred conditions are 0.2 to 0.8 mm of base group indentation, 5 to 250 mm / sec of stage movement speed, and 500 to 2,000 rpm of roller rotation speed. As an orientation processing method of a liquid crystal aligning film, the photo-alignment method, the transfer method, etc. other than the rubbing method are generally known. You may use together these other orientation processing methods in the said rubbing process in the range from which the effect of this invention is acquired.

The liquid crystal aligning film of this invention is obtained preferably also by the method of including the other process other than the above-mentioned process further. As such another process, the process of drying the said coating film, the process of washing the film before and behind a rubbing process with a washing | cleaning liquid, etc. are mentioned.

As for this drying process, the method of heat-processing in oven or infrared furnace, the method of heat-processing on a hotplate, etc. are generally known similarly to the said baking process. These methods can be similarly applied to the drying step. It is preferable to perform a drying process at the temperature within the range which can evaporate a solvent, and it is more preferable to carry out at relatively low temperature with respect to the temperature in the said baking process.

As a washing | cleaning method with the washing | cleaning liquid of the liquid crystal aligning film before and behind an orientation treatment, brushing, jet spray, steam washing | cleaning, ultrasonic washing | cleaning, etc. are mentioned. These methods may be performed independently or may be used together. Pure water or various alcohols such as methyl alcohol, ethyl alcohol and isopropyl alcohol, aromatic hydrocarbons such as benzene, toluene and xylene, halogen solvents such as methylene chloride, ketones such as acetone and methyl ethyl ketone can be used as the washing liquid. Although it is possible, it is not limited to these. Of course, these washing | cleaning liquids are refine | purified sufficiently and the thing with few impurities is used. Such a cleaning method is also applicable to the said washing process in formation of the liquid crystal aligning film of this invention.

Although the film thickness of the liquid crystal aligning film of this invention is not specifically limited, It is preferable that it is 10-300 nm, and it is more preferable that it is 30-150 nm. The film thickness of the liquid crystal aligning film of this invention can be measured by well-known film thickness measuring devices, such as a stepmeter and an ellipsometer.

The liquid crystal display element of this invention opposes a pair of board | substrate obtained by forming the liquid crystal aligning film of this invention in at least one, and opposes a liquid crystal aligning film through an spacer in an inner direction, sealing a liquid crystal composition in the clearance gap formed between board | substrates, and liquid crystal It is obtained by forming a layer. The above-mentioned glass substrate with an ITO electrode can be used for this board | substrate. The manufacture in the liquid crystal display element of this invention may also include new processes, such as affixing a polarizing film on a board | substrate as needed.

There is no restriction | limiting in particular in the said liquid crystal composition, Various liquid crystal compositions which have positive or negative dielectric anisotropy can be used. Preferred liquid crystal compositions having positive dielectric anisotropy include Japanese Patent No. 3086228, Japanese Patent No. 2635435, Japanese Patent Application Publication No. Hei 5-501735, Japanese Patent Application Publication No. Hei 8-157826, and Japanese Patent Japanese Patent Application Laid-open No. Hei 8-231960, Japanese Patent Application Laid-open No. Hei 9-241644 (EP 885272A1 specification), Japanese Patent Application Publication No. Hei 9-302346 (EP 806466A1 specification), Japanese Patent Application Publication No. Japanese Patent Application Publication No. Hei 9-235552, Japanese Patent Application Publication No. Hei 9-255956, Japanese Patent Application Publication No. Hei 9-241643 (EP 885271A1) ), Japanese Patent Application Publication No. Hei 10-204016 (EP 844229A1 specification), Japanese Patent Application Publication No. Hei 10-204436, Japanese Patent Application Publication No. Hei 10-231482, Japanese Patent Application Publication No. 2000- Publication 087040, Japan Heochulwon may be a liquid crystal composition that is disclosed in Laid-open No. 2001-48822 discloses.

Preferred liquid crystal compositions having negative dielectric anisotropy include Japanese Patent Application Laid-open No. 57-114532, Japanese Patent Application Laid-open No. 2-4725, Japanese Patent Application Laid-open No. 4-224885 and Japanese Patent Application Publication No. Hei 8-40953, Japanese Patent Application Publication No. Hei 8-104869, Japanese Patent Application Publication No. Hei 10-168076, Japanese Patent Application Publication No. Hei 10-168453, Japanese Patent Application Publication No. 10-236989, Japanese Patent Application Publication No. Hei 10-236990, Japanese Patent Application Publication No. Hei 10-236992, Japanese Patent Application Publication No. Hei 10-236993, Japanese Patent Application Publication No. Hei 10-23 236994, Japanese Patent Application Publication No. 10-237000, Japanese Patent Application Publication No. 10-237004, Japanese Patent Application Publication No. 10-237024, Japanese Patent Application Publication No. 10-237035 Gazette, Japanese patent application Japanese Patent Application Laid-open No. Hei 10-237075, Japanese Patent Application Publication No. Hei 10-237076, Japanese Patent Application Publication No. Hei 10-237448 (EP 967261A1 specification), Japanese Patent Application Publication No. Hei 10-287874, Japanese Patent Application Publication No. Hei 10-287875, Japanese Patent Application Publication No. Hei 10-291945, Japanese Patent Application Publication No. Hei 11-029581, Japanese Patent Application Publication No. Hei 11-080049, Japan Patent The liquid crystal composition disclosed in Unexamined-Japanese-Patent No. 2000-256307, Unexamined-Japanese-Patent No. 2001-019965, Unexamined-Japanese-Patent No. 2001-072626, Unexamined-Japanese-Patent No. 2001-192657, etc. are mentioned. have.

One or more optically active compounds may be added to the liquid crystal composition having the dielectric anisotropy being positive or negative.

The liquid crystal display element of this invention can form the liquid crystal display element for various electric field systems. In such a liquid crystal display element for an electric field system, a liquid crystal display element for a transverse electric field system in which the electrode applies a voltage to the liquid crystal layer in a horizontal direction with respect to the surface of the substrate, or in a direction perpendicular to the surface of the substrate. The liquid crystal display element for the vertical electric field system in which the said electrode applies a voltage to the said liquid crystal layer is mentioned.

Since the liquid crystal display element for a transverse electric field system does not need to express comparatively large pretilt angle, the alignment film by the liquid crystal aligning agent of this invention obtained from the diamine which does not contain the diamine which has a side chain is used preferably.

Since the liquid crystal display element for the electric field system requires the expression of a relatively large pretilt angle, the liquid crystal alignment film using the polymer A obtained from the diamine mixture containing the diamine represented by General formula (1) and the diamine which has a side chain is It is preferably used. In addition, when polymer A is a polymer obtained from the mixture of the diamine represented by General formula (1), and the diamine which does not have a side chain, the diamine mixture containing the diamine which has a side chain, or the diamine which has a side chain, and the diamine which does not have a side chain. The alignment film by the liquid crystal aligning agent of this invention which used the polymer B obtained from this is used preferably.

Thus, the liquid crystal aligning film manufactured using the liquid crystal aligning agent of this invention as a raw material can be applied to the liquid crystal display element of various display drive systems by selecting the polymer which is the raw material suitably.

[Example]

EXAMPLES Hereinafter, although the liquid crystal aligning agent and liquid crystal display element obtained by using the polymer of this invention are demonstrated in detail, this invention is not limited to these Examples. In Examples, GPC was used for the measurement of molecular weight, polystyrene was used as a standard solution, and eluate was used as DMF. In the following examples, L represents the unit liter of volume. Thus, mL means milliliters.

The evaluation method of the liquid crystal display element used by the Example below is described.

(1) Voltage retention rate (VHR)

The measurement was performed at the frequency of 30 Hz, a voltage of +/- 5V, and a measurement temperature of 60 degreeC using the "6254 type liquid-crystal physical-property evaluation system" by Toyo Technica. The larger this value, the better the electrical characteristics.

(2) Long-term high temperature reliability measurement

About the produced liquid crystal display element, voltage retention was calculated | required with time and the retention characteristic was evaluated. In the test method of the retention characteristics, the liquid crystal display element was left to stand for 500 hours in an atmosphere having a temperature of 100 ° C, and withdrawn over time, and the voltage retention measurement was measured. It can be said that the long-term high temperature reliability is good, so that the fall of the voltage retention after heating at 100 degreeC compared with the initial stage voltage retention is small.

(3) measurement of UV resistance

About the manufactured liquid crystal display element, light was irradiated to the whole element surface using the metal halide lamp as a light source. Irradiation wavelength was made into the wavelength range of 300-450 nm by using a filter, and it was performed at irradiation energy 8J / cm <2>. It can be said that UV resistance is so favorable that the fall of the voltage retention after light irradiation compared with initial voltage retention is small.

(4) Pretilt angle (Pt angle)

It measured at room temperature using the liquid crystal valuation apparatus (OMS-CA3) by the Nakae Seiki Co., Ltd. product.

The names of acid anhydrides, diamines, and solvents used in Examples and Comparative Examples are shown by the symbol. Subsequent descriptions may use this abbreviation.

<Acid anhydride>

1,2,3,4-cyclobutanetetracarboxylic dianhydride (acid anhydride (T6)): CBDA

Pyromellitic dianhydride (acid anhydride (T1)): PMDA

1,2,3,4-butanetetracarboxylic acid dianhydride (acid anhydride (T7)): BTDA

4,4'-ethane-1,2-diyl) bis (morpholine-2,6-dione): EDDA

<Diamine>

2,4-diamino-6-phenyl-1,3,5-triazine (diamine (1-9)): DPTA

2-Vinyl-4,6-diamino-1,3,5-triazine (diamine (1-7)): VDTA

2,4-diamino-6- (methacryloyloxy) ethyl-1,3,5-triazine (diamine (1-13)): ETZ

2,4-diamino-6-diallylamino-1,3,5-triazine (diamine (1-20)): AAZ

4,4'-diaminodiphenylmethane (diamine (3-1)): DDM

2,2'-dimethyl-4,4'-diaminodiphenylmethane (diamine (3-21)): MBMB

5-[[4-4'-pentyl [1,1'-bicyclohexyl] -4-yl) phenyl] methyl] -1,3-diaminobenzene (diamine (6- (5-1)): PBPB

Compound: 1,1-bis [4- (4-aminophenoxy) phenyl- (4-trans-4-n-pentylcyclohexyl) cyclohexane (diamine (5-23)): 5HHBA

1,2-bis (4-aminophenyl) ethane (diamine (3-2)): DET

<Solvent>

N-methyl-2-pyrrolidone: NMP

Butyl Cellosolve: BC

Synthesis Example 1

<Preparation of composition P1 (varnish P1) for liquid crystal aligning film>

In a 200 mL four-necked flask equipped with a thermometer, a stirrer, a raw material inlet, and a nitrogen gas inlet, 0.298 g of DPTA, 2.883 g of MBMB, 0.689 g of PBPB, and 58.3 mL of dehydrated NMP were added and stirred and dissolved under a dry nitrogen stream. . 2.50 g of CBDA and 0.631 g of BTDA were added while the temperature of the reaction system was maintained at 5 ° C, and after reacting for 30 hours, 36.6 mL of BC was added to prepare a varnish of polyamic acid having a polymer component concentration of 7% by weight. When reaction temperature rises by reaction heat during reaction of a raw material, reaction temperature was suppressed to about 70 degreeC or less and made it react.

The weight average molecular weight of the obtained polyamic acid was 108,500. The weight average molecular weight dilutes the obtained polyamic acid with a phosphoric acid-DMF mixed solution (phosphoric acid / DMF = 0.6 / 100: weight ratio) so that a polyamic acid concentration may be about 1 weight%, and a 2695 separation module and a 2414 differential refractometer (Waters company) Production), the mixed solution was used as a developing agent, measured by GPC method, and determined by polystyrene conversion. The column was HSPgel RT MB-M (manufactured by Waters Co., Ltd.) and measured under the conditions of a column temperature of 40 ° C. and a flow rate of 0.35 mL / min.

The varnish obtained as mentioned above was diluted with the mixed solvent of NMP / BC (weight ratio 50/50), and it adjusted so that the density | concentration of all the polymer components may be 3 weight%, and it was set as varnish P1 for application | coating.

Synthesis Examples 2-18

<Preparation of various varnishes>

Except having used the raw material shown in Table 1 in each molar ratio, varnish P2-P18 whose density | concentration of the total polymer component is 3 weight% was prepared by the method similar to varnish P1. The weight average molecular weight of the obtained polyamic acid is shown in Table 1 with the result of the synthesis example 1.

Example 1

<Production of Cell a for Voltage Retention Measurement>

Varnish P1 obtained in the synthesis example 1 was apply | coated with the spinner on the glass substrate with an ITO electrode. Application conditions were 1,700 rpm for 15 seconds. The board | substrate which apply | coated this varnish P1 was prebaked at 80 degreeC for about 5 minutes, and then heat-processed at 200 degreeC for 40 minutes, and the board | substrate for liquid crystal clamping with a liquid crystal aligning film whose film thickness is about 70 nm was obtained. This board | substrate was ultrasonically cleaned in ultrapure water for 5 minutes, and it dried at 120 degreeC in oven for 30 minutes. The 4 micrometers gap agent was spread | spreaded on the other glass substrate with an ITO electrode, and it sealed on the other glass substrate with an ITO electrode with an epoxy hardening | curing agent, and produced the cell of a gap of 4 micrometers. The liquid crystal material was injected into this cell, and the injection hole was sealed with the photocuring agent. Subsequently, heat processing were performed at 110 degreeC for 30 minutes, and it was set as the cell a for pretilt angle and voltage retention measurement. The composition of the liquid crystal composition A used as the liquid crystal material is shown below. The NI point of this composition was 75.4 ° C, and the birefringence was 0.081.

<Liquid crystal composition A>

Using this measuring cell a, the pretilt angle, voltage retention, long-term high temperature reliability, and UV resistance were measured. The measurement results are shown in Table 2.

EXAMPLES 2-8

Using the varnish P2 obtained in the synthesis examples 2 and 7-12, and varnishes P7-12, the measuring cell a was produced like Example 1, and the pretilt angle, voltage retention, long-term high temperature reliability, and UV tolerance were measured. The measurement results are shown in Table 2.

Comparative Example 1

Using varnish P3 obtained in Synthesis Example 3, measurement cell a was prepared in the same manner as in Example 1, and the pretilt angle, voltage retention, long-term high temperature reliability, and UV resistance were measured. The measurement results are shown in Table 2.

Example 9

Varnish P4 obtained by the synthesis example 4 was apply | coated with the spinner on the glass substrate with an ITO electrode. Application conditions were 1,700 rpm for 15 seconds. After preliminarily baking the board | substrate which apply | coated this varnish P4 for about 3 minutes at 80 degreeC, it heat-processed at 230 degreeC for 20 minutes, and obtained the board | substrate which formed the liquid crystal aligning film whose film thickness is about 70 nm. Using this liquid crystal aligning film, the Inuma Gauge Seisakusho-made rubbing processing apparatus, the amount of group foot indentation of the rubbing cloth (hair length 1.8 mm: rayon) was 0.40 mm, and the stage moving speed was 60 mm / sec, and the roller rotational speed. The rubbing process was performed on the conditions of 1,000 rpm, and the board | substrate for liquid crystal clamping was obtained. This board | substrate was ultrasonically cleaned in ultrapure water for 5 minutes, and it dried at 120 degreeC in oven for 30 minutes. A 7 micrometers gap agent was spread | spreaded on the other glass substrate with an ITO electrode, and it bonded to the other glass substrate with an ITO electrode with an epoxy hardening | curing agent, and produced the antiparallel cell of a gap of 7 micrometers. The liquid crystal material was injected into this cell, and the injection hole was sealed with the photocuring agent. Subsequently, heat processing were performed for 30 minutes at 110 degreeC, and it was set as the cell b for pretilt angle and voltage retention measurement. The composition of liquid crystal composition B used as a liquid crystal material is shown below. The NI point of this composition was 100.0 ° C, and the birefringence was 0.093.

<Liquid crystal composition B>

Pretilt angle, voltage retention, long-term high temperature reliability, and UV tolerance were measured using the obtained measurement cell b. The measurement results are shown in Table 3.

[Examples 10 to 16]

Using varnish P5 and varnishes P13 to P18 obtained in Synthesis Examples (5) and Synthesis Examples 13 to 18, a measuring cell b was prepared in the same manner as in Example 9, and the pretilt angle, voltage retention, long-term high temperature reliability and UV resistance Was measured. The measurement results are shown in Table 3.

Comparative Example 2

Using the varnish P6 obtained in the synthesis example 6, the measurement cell b was produced like Example 9, and the pretilt angle, voltage retention, long-term high temperature reliability, and UV tolerance were measured. The measurement results are shown in Table 3.

Synthesis Examples 19 to 22

Using the raw material shown in Table 4 in each molar ratio, the polyamic-acid solution of the polymer concentration of 7 weight% was obtained based on the synthesis example 1. Table 4 shows the weight average molecular weight of the obtained polyamic acid.

Example 17

A 7% by weight polyamic acid solution obtained in Synthesis Example 19 and a 7% by weight polyamic acid solution obtained in Synthesis Example 22 were mixed in a weight ratio of 10/90 (Synthesis Example 19 / Synthesis Example 22). The mixture was diluted with a mixed solvent of NMP / BC (weight ratio 50/50) to adjust the concentration of all polymer components to 3% by weight to obtain varnish P19 for coating. Using this varnish P19, the measurement cell a was produced like Example 1, and voltage retention, long-term high temperature reliability, and UV tolerance were measured. The measurement results are shown in Table 5.

Example 18

A 7% by weight polyamic acid solution obtained in Synthesis Example 20 and a 7% by weight polyamic acid solution obtained in Synthesis Example 22 were mixed at a weight ratio of 10/90 (Synthesis Example 20 / Synthesis Example 22). The mixture was diluted with a mixed solvent of NMP / BC (weight ratio 50/50) to adjust the concentration of all the polymer components to 3% by weight, thereby obtaining varnish P20 for coating. Using this varnish P20, the measurement cell a was produced similarly to Example 1, and voltage retention, long-term high temperature reliability, and UV tolerance were measured. The measurement results are shown in Table 5.

Comparative Example 3

A 7% by weight polyamic acid solution obtained in Synthesis Example 21 and a 7% by weight polyamic acid solution obtained in Synthesis Example 22 were mixed in a weight ratio of 10/90 (Synthesis Example 21 / Synthesis Example 22). The mixture was diluted with a mixed solvent of NMP / BC (weight ratio 50/50) to adjust the concentration of all the polymer components to 3% by weight, thereby obtaining varnish P21 for coating. Using this varnish P21, the measurement cell a was produced similarly to Example 1, and voltage retention, long-term high temperature reliability, and UV tolerance were measured. The measurement results are shown in Table 5.

As is clear from the results of Examples 1 to 18 and Comparative Examples 1 to 3, by using a polyamic acid having a diamine residue of the triazine skeleton in the structural unit, high voltage retention, long-term high temperature reliability (thermal reliability) and UV resistance ( Liquid crystal display device capable of satisfying light resistance) at the same time.

Claims (9)

The polyamic acid or its derivative obtained by making the diamine mixture which consists of one or more of the diamine represented by Formula (1) and one or more of other diamines with tetracarboxylic dianhydride be called polymer component A;
When the polyamic acid obtained by reacting at least one other diamine with tetracarboxylic dianhydride, or its derivative is called polymer component B;
Liquid crystal aligning agent which contains polymer component A as an essential component, and contains polymer component B as an arbitrary component:

In formula (1), R ¹ is hydrogen, -OH, -NH-C ₄ H ₉ , -N (CH ₃ ) ₂ , -N (C ₂ H ₅ ) ₂ , -N (CH ₂ CH = CH ₂ ) ₂ , -NH-CH ₂ CH = CH ₂ , halogen, alkyl of 1 to 20 carbon atoms, alkoxy of 1 to 20 carbon atoms, alkenyl of 2 to 20 carbon atoms, aryl of 6 to 20 carbon atoms, aryl of 7 to 20 carbon atoms Alkyl, or a structure of:

The method of claim 1,
Liquid crystal aligning agent whose R <^1> is vinyl or phenyl. The method according to claim 1 or 2,
Liquid crystal aligning agent whose said tetracarboxylic dianhydride is one or more of the compounds represented by Formula (T1)-a formula (T8):

The method of claim 3,
Liquid crystal aligning agent whose said tetracarboxylic dianhydride is one or more of the compound represented by Formula (T1), Formula (T6), and Formula (T7). The method according to any one of claims 1 to 4,
Liquid crystal aligning agent whose said other diamine is diamine chosen from the group of the compound represented by Formula (3)-Formula (6):

In the formula (3), Y is alkylene of 1 to 7 carbon atoms, and any -CH ₂ in the alkylene-being optionally substituted by -O- or -S-; R ² is independently alkyl having 1 to 3 carbons; k is independently 0 or 1;

In formula (4), X ¹ is independently -CH ₂ -or -O-; X ² is alkylene having 1 to 8 carbon atoms, and any hydrogen of this alkylene may be substituted with methyl or -CF ₃ ;

In formula (5), X <^1> is independently C1-C6 alkylene or -O-; X ³ is a single bond or alkylene having 1 to 3 carbon atoms, ring T is 1,4-phenylene or 1,4-cyclohexylene, and h is 0 or 1; R ³ is hydrogen or alkyl having 1 to 30 carbon atoms, and optionally -CH ₂ -of the alkyl may be substituted with -O-, -CH = CH- or -C≡C- when the carbon number is 2 to 30; ;

In formula (6), A ¹ is a single bond, -O-, -COO-, -OCO-, -CO-, -CONH-, -NHCO-, alkylene having 1 to 4 carbon atoms or 1,4-cyclo Hexylene; R ⁴ is a group having a steroid backbone, or a group represented by formula (A):

Wherein A ² and A ³ are independently a single bond, —O—, —COO—, —OCO—, —CONH—, —NHCO—, —CH═CH— or alkylene having 1 to 12 carbon atoms;
R ⁵ and R ⁶ are independently fluorine or methyl, f and g are independently an integer of 0 to 2; Ring S is 1,4-phenylene, 1,4-cyclohexylene, 1,3-dioxane-2,5-diyl, pyrimidine-2,5-diyl, pyridine-2,5-diyl, naphthalene- 1,4-diyl, naphthalene-1,5-diyl, naphthalene-2,6-diyl, naphthalene-2,7-diyl, or anthracene-9,10-diyl; R ⁷ is H, F, -OH, fluorinated alkyl, alkyl of 1 to 30 carbon atoms, 1 to 30 carbon atoms alkoxy of 1 to 30 carbon _{atoms, -CN, -OCH 2 F, -OCHF} 2 or -OCF _3, and;
c, d and e are independently integers of 0 to 3, wherein c + d + e ≧ 1; when e is 2 or 3, the plurality of rings S may all be the same ring, or may be composed of at least two different rings). The method according to any one of claims 1 to 5,
In the diamine mixture which consists of one or more of the diamine represented by Formula (1), and one or more of other diamine, the content rate of the diamine represented by Formula (1) is 5-30 mol% with respect to this diamine mixture whole quantity, Liquid crystal aligning agent. The method according to any one of claims 1 to 6,
The liquid crystal aligning agent containing only the polymer component A which is a polyamic acid or its derivative obtained by making the diamine mixture which consists of one or more of the diamine represented by Formula (1), and one or more of other diamines react with tetracarboxylic dianhydride. The liquid crystal aligning film obtained from the liquid crystal aligning agent in any one of Claims 1-7. The liquid crystal display element containing the liquid crystal aligning film of Claim 8.