TWI494292B - Diamine, liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display device - Google Patents

Description

Diamine, liquid crystal alignment agent, liquid crystal alignment film, and liquid crystal display element

The present invention relates to a novel diamine, and a liquid crystal alignment agent containing polyglycine or a derivative thereof and use thereof.

The liquid crystal display element includes a monitor (note personal computer) or a desktop computer monitor, a video camera view finder, and a projection display. It is used in liquid crystal display devices and has recently been used for television production. In addition, it can also be used as an optoelectronic related component such as an optical printer head, an optical fourier transform element, and a light valve.

The liquid crystal display device usually has: 1) a pair of substrates disposed opposite each other, 2) electrodes formed on one or both sides of the opposing faces of the pair of substrates, and 3) of the electrodes a liquid crystal alignment film formed on a surface facing each other of the substrate, and 4) a liquid crystal layer formed between the pair of substrates.

The mainstream of the prior liquid crystal display elements is a display element using nematic liquid crystal, and 1) a TN (Twisted Nematic) type liquid crystal display element which is twisted by 90 degrees, and 2) an STN which is generally distorted by 180 degrees or more ( A super Twisted Nematic (super twisted nematic) liquid crystal display element, 3) a TFT (Thin Film Transistor) liquid crystal display element using a thin film transistor, and the like have been put into practical use. These liquid crystal display elements have disadvantages in that the viewing angle of the image can be appropriately recognized, and when viewed from the oblique direction, a decrease in brightness or contrast and a brightness inversion of halftones are generated.

In recent years, the problem of this viewing angle has been improved and put into practical use by the following techniques: 1) a TN-TFT mode liquid crystal display element using an optical compensation film, and 2) a vertical alignment and an optical compensation film VA (Vertical Alignment, Vertical alignment mode liquid crystal display element, 3) MVA (Multi-Horizon Vertical Alignment) mode liquid crystal display element using vertical alignment and protrusion structure technology, or 4) transverse electric field mode IPS (In-Plane) Switching, coplanar switching) mode liquid crystal display elements, etc.

The development of liquid crystal display element technology can be achieved not only by the improvement of their driving methods or component structures, but also by the improvement of the constituent components used in the components. Among the constituent members used in the liquid crystal display element, in particular, the liquid crystal alignment film is one of important materials related to display quality, and as the liquid crystal display element is improved in quality, the performance of the alignment film is improved.

The liquid crystal alignment film is prepared by a liquid crystal alignment agent. The liquid crystal alignment agent which is mainly used now is a solution in which polylysine or soluble polyimine is dissolved in an organic solvent. After applying such a solution onto a substrate, a film is formed by heating or the like to form an alignment film. Although a liquid crystal alignment agent using a polymer other than polyamic acid has been studied, self-heat resistance, chemical resistance (liquid crystal resistance), coating properties, liquid crystal alignment, electrical properties, optical properties, display properties, and the like have been studied. In terms of consideration, it has not been put into practical use.

Such an alignment film requires the effects imparted to the liquid crystal display element as described below.

(1) A suitable pretilt angle is imparted to the liquid crystal molecules. Moreover, the pretilt angle is hardly affected by the pressing strength at the time of friction or the temperature condition at the time of heating.

(2) There is no occurrence of alignment defects of liquid crystal molecules due to unevenness in friction, scratches, or reduction of an alignment film.

(3) A suitable voltage holding ratio (VHR) is given to the liquid crystal display element.

(4) It is difficult to generate a phenomenon called "burn marks", which means that when a liquid crystal display element is displayed for a long time after an arbitrary image, when the image is changed to another image, the previous image is in the form of an afterimage. Residual.

The liquid crystal display element using the VA mode or the IPS mode has good viewing angle characteristics as described above, and thus the liquid crystal TV developed in recent years basically uses a liquid crystal display element of a VA mode or an IPS mode. When comparing the performance of the two modes, there are respective strengths and weaknesses due to the driving principle. For example, in the case of the IPS mode, the viewing angle characteristics are particularly good, and the response speed in halftones is relatively fast. However, the contrast is poor compared to the VA mode. The IPS mode is black when no voltage is applied, and this state depends on the initial alignment state of the liquid crystal due to friction, which is one of the causes of deterioration of contrast. That is, in the IPS alignment film, an alignment film having a high liquid crystal alignment property and black display (good black level) is strongly required. Patent Document 1 can be cited as an example of the prior art for solving such a problem. However, the technique of this document is characterized in that a diamine having a triple bond at the end is used, and the effect is not confirmed in the liquid crystal display element of the IPS mode.

Prior technical literature

Patent literature

Patent Document 1: Japanese Patent Laid-Open Publication No. 2009-300940

An object of the present invention is to develop a liquid crystal alignment agent for obtaining a liquid crystal alignment film having high liquid crystal alignment properties and good black level.

The present inventors have found that by using a liquid crystal alignment agent composed of polyproline or a derivative thereof (in which the diamine having a specific structure is used as one of raw materials), A liquid crystal display element which satisfies the above-mentioned required characteristics is obtained, thereby completing the present invention.

According to the present invention, a liquid crystal alignment agent having good alignment property can be obtained. Especially effective for the improvement of the black level of the IPS mode. Further, according to the present invention, it is also possible to obtain an effect of obtaining an alignment film having a small volume resistance value.

The present invention includes the following constitutions.

[1] A diamine represented by the formula (I),

[Chem. 24]

(wherein R is a sulfonyl group having a methylene group interposed on a nitrogen atom and a hydroxyl group bonded to a terminal at the terminal).

[2] The diamine according to [1], wherein R is represented by (a), (b) or (c),

[化25]

(wherein R ⁰ is hydrogen or methyl).

[3] The diamine according to [2], wherein R ⁰ is hydrogen.

[4] The diamine according to any one of [1], wherein, in the formula (I), the two amino groups are substituted for the 3-position and the 5-position, respectively, with respect to the substituent represented by R. Bit.

[5] A poly-proline and a derivative thereof, wherein at least one of the diamines represented by the formula (I) and the tetracarboxylic dianhydride according to any one of [1] to [4] The reaction is obtained.

[6] A poly-proline and a derivative thereof, which is at least one of the diamine represented by the formula (I) and the other diamine (D2) according to any one of [1] to [4]. The mixture is obtained by reacting with a tetracarboxylic dianhydride.

[7] The poly-proline and the derivative thereof according to [5] or [6], wherein the tetracarboxylic dianhydride is selected from the group consisting of the following formula (DA-20) to formula (DA-32) One or more groups,

[Chem. 26]

In the formula (DA-20), G ⁵ is a single bond, an alkylene group having a carbon number of 1 to 12, a 1,4-phenylene group or a 1,4-cyclo ring. 1,4-cyclohexylene; X ^{10 is} independently a single bond or CH ₂ ; and G ^{6 is} independently CH or N. When G ⁶ is N, G ⁵ is not a single bond or CH ₂ , X ¹⁰ is not a single button;

[化27]

In the formula (DA-21), R ^{14 is} independently hydrogen, methyl, ethyl or phenyl;

[化28]

In the formula (DA-22), the ring A ⁶ is a cyclohexane ring or a benzene ring;

[化29]

In the formula (DA-23), G ⁷ is a single bond, an alkylene group having 1 to 10 carbon atoms, 1,4-phenylene group, O, CO, S, SO ₂ , C(CH ₃ ) ₂ or C(CF ₃ ) ₂ ; Moreover, ring A ^{7 is} independently a cyclohexane ring or a benzene ring;

[化30]

In the formula (DA-24), R ¹⁵ is hydrogen or methyl;

[化31]

In the formula (DA-25), X ¹⁰ is a single bond or CH ₂ ; X ^{11 is} independently CH ₂ , CH ₂ CH ₂ or CH=CH; and, v is 1 or 2;

[化32]

In formula (DA-26), X ¹⁰ is a single bond or CH ₂ ;

[化33]

In the formula (DA-27), R ¹⁴ is hydrogen, methyl, ethyl or phenyl; ring A ⁸ is a cyclohexane ring, a cyclohexene ring or a benzene ring; and, X ¹² is a single bond, CH ₂ Or CH(CH ₃ );

[化34]

In the formula (DA-28), w2 and w3 are 0 or 1, and when w2=1, w3=1;

[化35]

[化36]

In the formula (DA-30), X ^{13 is} independently an alkyl group having 2 to 6 carbon atoms; and, Ph represents a phenyl group;

[化37]

[化38]

In the formula (DA-32), X ¹⁴ independently represents a single bond or CH ₂ .

[8] The poly-proline and the derivative thereof according to any one of [6] to [7] wherein the other diamine (D2) is represented by the following formula (1-1) to formula (4) Diamine,

[39]

In the formula (1-1), b is 0 or 1; any hydrogen in the cyclohexylene group may also be substituted by a methyl group; in the formula (1-2), W ¹ is -CH ₂ - or -NH- ;

[化40]

Here, X ¹ is a single bond or an alkylene group having 1 to 10 carbon atoms; any -CH ₂ - of the alkylene group may also be -O-, -S-, -NH-, -N(CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CF ₃ ) ₂ -, -CO-, -SO ₂ -, 1,3-phenylene, 1,4-phenylene or pyridazine- 1,4-diyl (piperazine-1,4-diyl) substitution;

[化41]

In the formula (3), X ² is a single bond, -O-, -COO-, -OCO- or an alkylene group having 1 to 6 carbon atoms; R ¹ is an alkyl group having 3 to 30 carbon atoms, or a group represented by the formula (a); in the formula (a), X ³ and X ^{4 are} independently a single bond or an alkylene group having 1 to 4 carbon atoms; and ring B and ring C are independently a 1,4-phenylene group. Or 1,4-cyclohexylene; R ² and R ^{3 are} independently fluoro or methyl, and f and g are independently 0, 1 or 2; c, d and e are independently 0 or 1, and c, d and The total of e is 1 to 3; R ⁴ is an alkyl group having 1 to 30 carbon atoms, an alkoxy group having 1 to 30 carbon atoms, an alkoxyalkyl group having 2 to 30 carbon atoms or cholesteryl. In the alkyl, alkoxy and alkoxyalkyl groups, any hydrogen may also be substituted by fluorine;

[化42]

Here, X ^{5 is} independently -O- or an alkylene group having 1 to 6 carbon atoms; j is independently 0 or 1; R ⁵ is hydrogen, an alkyl group having 2 to 12 carbon atoms or a carbon number of 2 to 12 Alkoxy; ring T is 1,4-phenylene or 1,4-cyclohexylene; X ⁶ is a single bond or an alkylene group having 1 to 3 carbon atoms; h is 0 or 1.

[9] The poly-proline and the derivative thereof according to any one of [6], wherein the other diamine (D2) is at least one selected from the group consisting of the following compounds,

[化43]

(wherein R ¹¹ is -CH ₂ -, -O- or a linear alkylene group having 1 to 4 carbon atoms; R ¹² is hydrogen or CH _{3 ;} and R ¹³ is a linear subgroup having 2 to 4 carbon atoms; An alkyl group, R ¹⁴ is a linear alkylene group having 1 to 8 carbon atoms, R ^{15 is} independently -CH ₂ -, -(CH ₂ ) ₂ -, or -NH-, and R ¹⁶ is a hydrogen atom or a carbon number. a linear alkylene group of 1 to 10, R ¹⁷ is a hydrogen atom or a linear alkylene group having 1 to 16 carbon atoms, and R ^{18 is} independently -CH ₂ -, -(CH ₂ ) ₂ - or -O -).

[10] A composition comprising at least one polymer selected from the group consisting of polylysines and derivatives thereof according to any one of [5] to [9].

[11] A liquid crystal alignment agent comprising a composition containing at least one polymer selected from the group consisting of polyamino acids described in [5] to [9] and derivatives thereof.

[12] The liquid crystal alignment agent according to [11], which comprises an epoxy compound (E).

[13] The liquid crystal alignment agent according to [12], wherein the epoxy compound (E) is one or more selected from the group consisting of compounds represented by the following formulas (E1) to (E6),

[化44]

(wherein n is an integer of 1 to 10).

[14] The liquid crystal alignment agent according to [11], which comprises an oxazoline compound (F).

[15] The liquid crystal alignment agent according to [14], wherein the oxazoline compound (F) is a compound represented by the following formula (F1),

[化45]

[16] The liquid crystal alignment agent according to [11], which comprises a bisallyl-diadiimide compound (G).

[1] The liquid crystal alignment agent according to [16], the bisallyl nadic ylidene imine compound (G) is a group selected from the group consisting of compounds represented by the following formula (G1) and formula (G2) One or more types,

[Chem. 46]

[18] The liquid crystal alignment agent according to [11], which comprises a group selected from the group consisting of the compounds represented by the above (E1) to (E6), (F1), (G1), and (G2) More than one species.

[19] A liquid crystal alignment film which is formed by the liquid crystal alignment agent according to any one of [11] to [18].

[20] A liquid crystal display element comprising the liquid crystal alignment agent according to any one of [11] to [18].

The diamine of the present invention can be represented by the following formula (I).

[化47]

(wherein R is a sulfonyl group having a methylene group interposed on a nitrogen atom and a hydroxyl group bonded to a terminal at the terminal.)

In the formula (I), R is more preferably a diamine represented by the following (a), (b) or (c).

[48]

(wherein R ⁰ is hydrogen or methyl.)

The compound represented by the formula (I) wherein R is (a) or (b) can be synthesized by the method shown in Scheme 1.

Process 1.

[化49]

The dinitrobenzamide chloride is reacted with an amine compound in the presence of a base such as triethylamine to obtain a dinitrobenzamide compound. The diamine of the present invention is obtained by reduction of the nitro group. In the scheme 1, R ⁰ is hydrogen or a methyl group, and R' is a structure represented by the following.

[化50]

The compound represented by the formula (I) wherein R is (c) can be synthesized by the method shown in Scheme 2.

Process 2.

[化51]

The dinitrobenzamide is reacted with diethanolamine in the presence of a base such as triethylamine to obtain a dinitrobenzamide compound. The diamine of the present invention is obtained by reduction of the nitro group.

The liquid crystal alignment agent of the present invention is a composition containing at least one polymer selected from the group consisting of polyamic acid and derivatives thereof, and a solvent. Examples of the derivative of polyproline include a polyimine obtained by subjecting polylysine to a complete dehydration ring-closure reaction, and a partial ruthenium polyisamic acid obtained by subjecting polylysine to partial dehydration ring closure reaction. a polyglycolic acid ester, a poly-proline-polyamine copolymer obtained by replacing a part of a tetracarboxylic dianhydride with a dicarboxylic acid, or a part of the poly-proline-polyamine copolymer or The polyamine-quinone imine obtained by performing a dehydration ring closure reaction. Among these compounds, polyimine and partial ruthenium polyamine are preferred, and polyimine is more preferred.

In the present invention, at least one selected from the group consisting of polylysine and a derivative thereof obtained by reacting a mixture of a diamine represented by the formula (I) and another diamine (D2) with an acid dianhydride 1 polymer.

Specific examples of the diamine represented by the formula (I) used in the present invention are the following (I-1) to (I-10), and these diamines may be used in combination or only one type may be used. Further, among these compounds, a compound of (I-5) or (I-9) is particularly preferable.

[化52]

In the case where a liquid crystal alignment agent is prepared by using a diamine (D2) other than the compound of the present invention, in order to further achieve the effects of the present invention, the ratio of the compound (I) of the present invention is preferably relative to the total amount of the diamine used. It is 5 mol% to 100 mol%, more preferably 5 mol% to 95 mol%, and most preferably 20 mol% to 80 mol%.

The diamine (D2) used in the present invention can be selected from known diamines without any limitation. Preferred diamines include diamines (1-1) to diamines (1-3) shown below. Diamine (2), diamine (3) and diamine (4). It is preferred to use at least one diamine selected from the group of these diamines.

[化53]

In the formula (1-1), b is 0 or 1, and any hydrogen in the cyclohexylene group may be substituted with a methyl group.

In the formula (1-2), W ¹ is -CH ₂ - or -NH-.

Specific examples of these diamines (D2) are shown below. In the following specific examples, a diamine is particularly preferable from the viewpoint of further improving the alignment of the liquid crystal, the viewpoint of improving the VHR of the liquid crystal display element, and the viewpoint of improving the relaxation rate of the residual DC in the alignment film. 1-2-1) and diamine (1-3).

[54]

[化55]

In the formula (2), X ¹ is a single bond or an alkylene group having 1 to 10 carbon atoms, and any -CH ₂ - of the alkylene group may be -O-, -S-, -NH-, -N(CH ₃ )-, -C(CH ₃ ) ₂ -, -C(CF ₃ ) ₂ -, -CO-, -SO ₂ -, 1,3-phenylene, 1,4-phenylene Or a pyridazine-1,4-diyl group. A preferred example of X ¹ is an alkylene group having 1 to 10 carbon atoms, and any -CH ₂ - of the alkylene group may also be -O-, -S-, -NH-, -C(CH ₃ ). _2- , 1,4-phenylene or pyridazine-1,4-diyl substitution. Further, any hydrogen of the benzene ring to which the amino group is bonded may be substituted by a methyl group, but is preferably not substituted by a methyl group.

Specific examples of the diamine (2) are shown below.

[化56]

[化57]

[化58]

[化59]

[60]

In the formula (3), X ² is a single bond, -O-, -COO-, -OCO- or an alkylene group having 1 to 6 carbon atoms, preferably a single bond, -O-, -COO- or carbon. The number is 1 to 3 alkylene groups. R ¹ is an alkyl group having 3 to 30 carbon atoms or a group represented by the formula (a), and is preferably an alkyl group having 4 to 20 carbon atoms or a group represented by the formula (a).

In the formula (a), X ³ and X ^{4 are} independently a single bond or an alkylene group having 1 to 4 carbon atoms, preferably a single bond, -CH ₂ - or -CH ₂ CH ₂ -. Ring B and Ring C are independently 1,4-phenylene or 1,4-cyclohexylene. R ² and R ^{3 are} independently fluorine or methyl, and f and g are independently 0, 1, or 2, but it is preferable that both f and g are 0. c, d, and e are independently 0 or 1, and the total of c, d, and e is 1 to 3. R ⁴ is an alkyl group having 1 to 30 carbon atoms, an alkoxy group having 1 to 30 carbon atoms or an alkoxyalkyl group having 2 to 30 carbon atoms, and the alkyl group, alkoxy group and alkoxy group. In the alkyl group, any hydrogen may be substituted by fluorine. Preferable examples of R ⁴ are an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and an alkoxyalkyl group having 2 to 20 carbon atoms, and the alkyl group, alkoxy group and alkane. The hydrogen in the oxyalkyl group is not substituted by fluorine.

Preferred examples of the diamine (3) are shown below.

[化61]

[化62]

In the formulae (3-1) to (3-25), R ²⁰ is an alkyl group having 1 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, preferably an alkane having 5 to 16 carbon atoms. base. R ²¹ is an alkyl group having 1 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, and preferably an alkyl group having 3 to 10 carbon atoms. R ²² is an alkyl group or a cholesteryl group having 4 to 20 carbon atoms, preferably an alkyl group having 6 to 16 carbon atoms or a cholesteryl group. R ²³ is an alkyl group having 4 to 20 carbon atoms, and preferably an alkyl group having 6 to 16 carbon atoms. R ²⁴ is an alkyl group having 3 to 20 carbon atoms or an alkoxy group having 3 to 20 carbon atoms, and preferably an alkyl group having 5 to 12 carbon atoms.

[化63]

In the formula (4), X ^{5 is} independently -O- or an alkylene group having 1 to 6 carbon atoms, and preferably both -O-, -CH ₂ - or -CH ₂ CH ₂ -. j is independently 0 or 1. R ⁵ is hydrogen, an alkyl group having 1 to 20 carbon atoms or an alkoxy group having 1 to 20 carbon atoms, preferably hydrogen, an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms. More preferably, it is an alkyl group having 4 to 7 carbon atoms. Ring T is 1,4-phenylene or 1,4-cyclohexylene. X ⁶ is a single bond or an alkylene group having 1 to 3 carbon atoms. Moreover, h is 0 or 1. Further, the bonding position of the amino group to the benzene ring is preferably para-position with respect to X ⁵ .

Preferred examples of the diamine (4) are shown below.

[化64]

[化65]

In the formulae (4-1) to (4-16), R ²⁶ is hydrogen, an alkyl group having 1 to 12 carbon atoms or an alkoxy group having 1 to 12 carbon atoms, and preferably having 4 to 7 carbon atoms. Alkyl.

In the specific example of the above diamine (D2), the diamine (1-2-1), the diamine (1-3), and the diamine (2-1) to the diamine (2-3) shown below are more preferable. , diamine (2-7), diamine (2-10) to diamine (2-27), diamine (2-29), diamine (2-37) to diamine (2-41), two Amine (2-43) to diamine (2-47), diamine (2-51), diamine (3-1) to diamine (3-12-1), and diamine (4-1)~ Diamine (4-12).

[化66]

[67]

[化68]

[化69]

Here, R ²⁰ is an alkyl group having 5 to 16 carbon atoms, and R ²¹ is an alkyl group having 3 to 10 carbon atoms.

[化70]

Here, R ²⁶ is an alkyl group having 4 to 7 carbon atoms.

In a specific example of the above-described more preferable diamine (D2), when the liquid crystal alignment property is further improved, diamine (1-2-1), diamine (1-3), and diamine are more preferable. (2-7), diamine (2-10) to diamine (2-12), diamine (2-16) to diamine (2-19), diamine (2-21) to diamine (2 -27), diamine (2-37) to diamine (2-41), diamine (2-43) to diamine (2-47), diamine (2-51), diamine (3-1 -diamine (3-11) and diamine (4-1) to diamine (4-12), particularly preferably diamine (1-2-1), diamine (1-3), diamine (2) -7), diamine (2-10) to diamine (2-12), diamine (2-26), diamine (2-44), diamine (2-45) and diamine (3-1 ) ~ Diamine (3-6).

In a specific example of the above-described more preferable diamine (D2), when it is important to impart a high VHR to the liquid crystal alignment film, diamine (1-2-1), diamine (1-3), and second are more preferable. Amine (2-1) to diamine (2-3), diamine (2-26), diamine (2-29), diamine (2-37), diamine (2-43) to diamine ( 2-47), diamine (3-1) to diamine (3-11), and diamine (4-1) to diamine (4-12), particularly preferably diamine (2-1) to diamine ( 2-3), diamine (2-26), diamine (2-29), diamine (2-44), and diamine (3-1) to diamine (3-6).

In a specific example of the above-described more preferable diamine (D2), when it is important to reduce the volume resistivity of the liquid crystal alignment film, diamine (1-2-1) and diamine (1-3) are more preferable. , diamine (2-1) to diamine (2-3), diamine (2-13) to diamine (2-15), diamine (2-20) to diamine (2-26), Amine (2-29) and diamine (2-39) to diamine (2-41), particularly preferably diamine (2-1) to diamine (2-3), diamine (2-13) to Amine (2-15), diamine (2-26) and diamine (2-29).

However, diamines can be classified into two types depending on their structures. That is, when the skeleton linking two amino groups is regarded as a main chain, a diamine having a branch of an autonomous chain, that is, a side chain group, and a diamine having no side chain group. By reacting a diamine having a side chain group with a tetracarboxylic dianhydride, a polylysine having a plurality of side chain groups for the main chain of the polymer is obtained. When such a polyamic acid having a side chain group for the polymer main chain is used, the liquid crystal alignment film formed of the liquid crystal alignment agent containing the polymer can increase the pretilt angle in the liquid crystal display element. That is, the side chain group is a group having an effect of increasing the pretilt angle. The side chain group having such an effect must be a group having 3 or more carbon atoms, and specific examples thereof include an alkyl group having 3 or more carbon atoms, an alkoxy group having 3 or more carbon atoms, and an alkane having 3 or more carbon atoms. The group of oxyalkyl groups. The ring having one or more rings and having a terminal having a C 1 or more alkyl group, an Alkoxy group having 1 or more carbon atoms, and an alkoxyalkyl group having 2 or more carbon atoms as a substituent The base also has an effect as a side chain group. When a diamine having such a side chain group is used as a side chain type diamine, and a diamine having no such side chain group is used as a non-side chain type diamine, the diamine (3) and the diamine (4) It is a side chain type diamine, a diamine (1-1) to a diamine (1-3), and a diamine (2) is a non-side chain type diamine.

Further, by suitably separating the side chain type diamine from the non-side chain type diamine, it is possible to correspond to the pretilt angle necessary for each of the display elements. That is, in the longitudinal electric field method represented by the TN method or the VA method, a large pretilt angle must be relatively large, and therefore a side chain type diamine is mainly used. At this time, in order to further control the pretilt angle, a non-side chain type diamine may also be used in combination. The blending ratio of the non-side chain type diamine to the side chain type diamine can be determined according to the target pretilt angle. Of course, by appropriately selecting the side chain group, it is also possible to use only the side chain type diamine. In the transverse electric field method, a small pretilt angle and a high liquid crystal alignment property are required, and therefore at least one type of non-side chain type diamine can be used.

In the present invention, in particular, in order to exhibit a pretilt angle of 2 or more, it is preferred to use a side chain type diamine in a proportion of 5 mol% to 70 mol%, more preferably 10 mol% to 50% based on the total amount of the diamine. Mol%.

The tetracarboxylic dianhydride (hereinafter sometimes simply referred to as "anhydride") used for the synthesis of the polyglycolic acid of the present invention can be selected from known acid anhydrides without limitation, and preferred examples thereof include the following acid anhydrides (for example) A-1) to an acid anhydride (A-48). It is preferred to use at least one of these acid anhydrides.

[71]

[化72]

[化73]

Among the above acid anhydrides, the acid anhydride (A-1) to the acid anhydride (A-4), the acid anhydride (A-11), the acid anhydride (A-12), the acid anhydride (A-14), the acid anhydride (A-15), and the acid anhydride are more preferable. A-16), acid anhydride (A-20) to acid anhydride (A-23), acid anhydride (A-30) to acid anhydride (A-32), acid anhydride (A-34), acid anhydride (A-39), acid anhydride (A) -41) to an acid anhydride (A-43) and an acid anhydride (A-45) to an acid anhydride (A-48).

In the case where the liquid crystal alignment property is further improved, the acid anhydride (A-1), the acid anhydride (A-2), the acid anhydride (A-12), the acid anhydride (A-14), and the acid anhydride (A-15) are more preferable among the above acid anhydrides. ), Anhydride (A-16), Anhydride (A-20), Anhydride (A-22), Anhydride (A-23), Anhydride (A-30), Anhydride (A-32), Anhydride (A-39) The acid anhydrides (A-42) and (A-47) are particularly preferably an acid anhydride (A-1), an acid anhydride (A-12), an acid anhydride (A-14), an acid anhydride (A-20), and (A-47).

When attention is paid to the case where the VHR of the liquid crystal display element is increased, an acid anhydride (A-16), an acid anhydride (A-20), an acid anhydride (A-21), an acid anhydride (A-22), and an acid anhydride (A) are more preferable among the acid anhydrides. -23), acid anhydride (A-30), acid anhydride (A-31), acid anhydride (A-32), acid anhydride (A-34), acid anhydride (A-41), acid anhydride (A-42), acid anhydride (A- 43) an alicyclic compound of an acid anhydride (A-45), an acid anhydride (A-46) and an acid anhydride (A-48), particularly preferably an acid anhydride (A-16), an acid anhydride (A-22), an acid anhydride (A-23) ), anhydride (A-41), anhydride (A-46), and anhydride (A-48).

The polyphthalic acid used in the liquid crystal alignment agent of the present invention can be obtained by reacting a mixture of the above acid anhydrides with a diamine in a solvent. In the synthesis reaction, no special conditions are required except for the selection of the raw materials, and the conditions in the usual synthesis of polyamic acid can be directly applied. The solvent to be used will be described later.

In the liquid crystal alignment agent of the present invention, at least one type of a naphthenic-based diamine may be used in combination in order to prevent reduction due to friction. Preferable examples of the oxirane-based diamine include a diamine represented by the formula (15).

[化74]

Here, R ³⁰ and R ^{31 are each} independently an alkyl group having 1 to 3 carbon atoms or a phenyl group, and R ³² is an alkylene group having 1 to 6 carbon atoms, a phenylene group or a phenylene group substituted by an alkyl group. Y is an integer of 1 to 10.

Specific examples of the diamine (15) include the following compounds or polymers.

[化75]

(The molecular weight of the polymer of the formula (15-2) is 850 to 3,000.)

When these azepine-based diamines are used, in order to exhibit the above effects and prevent deterioration of other properties, the amount of addition is preferably 0.5 mol% to 30 mol% based on the total amount of the diamine used as a raw material. More preferably, it is 1 mol% - 10 mol%.

The alignment agent of the present invention may further contain an organic ruthenium compound from the viewpoint of adjusting the adhesion of the alignment film to the glass substrate. Examples of organic hydrazine compounds are aminopropyltrimethoxydecane, aminopropyltriethoxydecane, vinyltrimethoxydecane, N-(2-aminoethyl)-3-aminopropylmethyldimethoxy Baseline, N-(2-aminoethyl)-3-aminopropyltrimethoxydecane, vinyltriethoxydecane, 3-methylpropenyloxypropyltrimethoxydecane, 3-glycidol a decane coupling agent such as oxypropyltrimethoxydecane, 3-glycidoxypropylmethyldimethoxydecane or 2-(3,4-epoxycyclohexyl)ethyltrimethoxydecane, and An eucalyptus oil such as dimethyl polyoxane, polydimethyl siloxane or polydiphenyl siloxane.

The addition ratio of the organic ruthenium compound to the alignment agent is not particularly limited as long as it is within the range in which the effects of the present invention are obtained. However, when the organic ruthenium compound is added in a large amount, there is a phenomenon in which liquid crystal alignment failure occurs when the alignment film is formed. Therefore, when the organic ruthenium compound is added, the concentration thereof is preferably in the range of 0.01% by weight to 5% by weight based on the weight of the polymer contained in the aligning agent, and particularly preferably in the range of 0.1% by weight to 3% by weight.

The alignment agent of the present invention may further contain a compound having two or more functional groups reactive with a carboxyl group of poly-proline or a derivative thereof, from the viewpoint of preventing degradation of the characteristics over time or deterioration by the environment. The so-called cross-linking agent. Examples of such a crosslinking agent include a polyfunctional epoxy material, an isocyanate material, and the like described in JP-A No. 3049699, JP-A-2005-275360, and JP-A No. 10-212484.

One of the causes of deterioration of the electrical characteristics of the liquid crystal display element over time is that other components for forming a liquid crystal display element, such as a liquid crystal compound or a sealant, are adsorbed to the alignment film due to the influence of the carboxyl group remaining in the alignment film. The resulting interaction. When the polyfunctional epoxy compound represented by the above (E1) to (E5) is contained in the liquid crystal alignment agent of the present invention, the residual carboxylic acid of the polyimine is in the step of forming the alignment film (that is, the heating step). The epoxy compound reacts to form a more chemically stable group, specifically an ester group, which reduces interaction with other components. Therefore, even if the liquid crystal display element is used for a long time, the initial electrical characteristics can be maintained. Moreover, by using a polyfunctional epoxy compound, there is also an effect of crosslinking the polyimine forming a liquid crystal alignment agent with each other, the initial alignment state can be maintained, and the electrical characteristics of the liquid crystal display element can be stabilized for a long period of time, and display can be prevented. Deterioration of quality. Further, when the epoxy compound containing ruthenium represented by (E6) is contained, not only the above-described residual carboxylic acid acts but also the adhesion of the alignment film to the glass substrate can be improved. As a result, in the rubbing treatment of the alignment film which is carried out in the production step of the liquid crystal display element, it is possible to prevent the alignment film from being peeled off from the glass substrate.

The alignment agent of the present invention may further contain an oxazoline compound and/or an oxazine compound from the viewpoint of stabilizing the electrical characteristics of the liquid crystal display element for a long period of time. The oxazoline compound refers to a compound having an oxazoline structure in a molecule. By adding an oxazoline compound, a carboxyl group remaining in the alignment film is reacted with an oxazoline compound in a step of forming an alignment film (heating step) to form a more stable group, specifically a guanamine group, thereby Make electrical properties stable for a long time. In addition, the term "stabilized group" as used herein does not mean the stability of the organic group itself, but means a group having little effect such as adsorption of other substances such as liquid crystal compounds in the display element. Further, by using a compound having two or more oxazoline structures as a crosslinking agent, the initial alignment state can be maintained for a long period of time. As a result, the electrical characteristics of the liquid crystal display element can be stabilized for a long period of time, and deterioration of display quality can be prevented. Specific examples of the oxazoline compound are 2,2'-bis(2-oxazoline), 1,2,4-tris-(2-oxazolinyl-2)-benzene, 4-furan-2-yl Methylene-2-phenyl-4H-oxazol-5-one, 1,4-bis(4,5-dihydro-2-oxazolyl)benzene, 1,3-bis(4,5-di Hydrogen-2-oxazolyl)benzene, 2,3-bis(4-isopropenyl-2-oxazolin-2-yl)butane, 2,2'-bis-4-benzyl-2-oxo Oxazoline, 2,6-bis(isopropyl-2-oxazolin-2-yl)pyridine, 2,2'-isopropylidene bis(4-tert-butyl-2-oxazoline), 2,2'-isopropylidene bis(4-phenyl-2-oxazoline), 2,2'-methylenebis(4-tert-butyl-2-oxazoline), and 2, 2'-methylenebis(4-phenyl-2-oxazoline). In addition to these compounds, a polymer or oligomer having an oxazolyl group such as EPOCROS (trade name, manufactured by Nippon Shokubai Co., Ltd.) can be exemplified. Among the oxazoline compounds, in particular, if 1,3-bis(4,5-dihydro-2-oxazolyl)benzene (a compound represented by the compound (F1)) is used, the liquid crystal may not be used. The original characteristics of the alignment film are lowered to prevent deterioration of the liquid crystal display element over time. The content of the oxazoline compound can be from 0.1% by weight to 50% by weight based on the total amount of the polymer component. The content of the oxazoline compound is preferably from 1% by weight to 40% by weight, more preferably from 1% by weight to 20% by weight.

The oxazide compound refers to a compound having an oxazine structure in a molecule, and various structures are known. The structure of the oxazine compound to be used in the present invention is not particularly limited, and examples thereof include an oxazine structure having an aromatic group (including a condensed polycyclic aromatic group) such as benzoxazine or naphthoazine. Examples of the oxazine compound include compounds described in, for example, the specification of the International Publication No. 2004/009708, the Japanese Patent Laid-Open No. Hei 11-12258, and the Japanese Patent Publication No. 2004-352670. The content of the oxazine compound is from 0.1% by weight to 50% by weight based on the total amount of the polymer component. The content of the oxazine compound is preferably from 1 wt% to 40 wt%, more preferably from 1 wt% to 20 wt%.

Further, the crosslinking agent itself reacts to form a polymer having a network structure, and a crosslinking agent for increasing the film strength of polyglycolic acid or polyimine can also be used for the same purpose as described above. The polyfunctional vinyl ether, maleimide, or the above compound (G1) and the compound described in JP-A-2004-341030, and the like are exemplified in the above-mentioned Japanese Patent Publication No. 2004-341030. A bisallyl nadic ylidene derivative represented by (G2) or the like. When these crosslinking agents are used, the preferred ratio thereof is from 5 wt% to 100 wt%, more preferably from 10 wt% to 50 wt%, based on the total amount of the polymer component.

In the liquid crystal alignment agent of the present invention, at least one polylysine is preferably used, and polylysine may be used in combination with other polyamine produced without using the diamine (I) of the present invention. The mixing ratio in the case of combining other polylysines is 10% by weight to 95% by weight based on the total amount of the polymer, and the other polylysine is 5% by weight. ～90 wt%, a sufficient effect can be obtained even if the proportion of the polyaminic acid of the present invention is small. In the liquid crystal alignment agent of the present invention, a polymer other than polyamic acid obtained by reacting an acid anhydride with a diamine, for example, a polyester or an epoxy resin, may be used in combination. However, when such other polymers are used in combination, the proportion thereof is preferably 30% by weight or less based on the total weight of the polymer.

The alignment agent of the present invention is a solution obtained by dissolving polylysine in a solvent. The solvent can be appropriately selected from the solvents used in the production or use of the known polyamic acid according to the purpose of use. If these solvents are exemplified, they are as follows.

Examples of the aprotic polar organic solvent include N-methyl-2-pyrrolidone (NMP), dimethyl imidazolidinone, N-methyl caprolactam, N-methylpropionamide, N, N. - dimethylacetamide, dimethyl hydrazine, N,N-dimethylformamide (DMF), N,N-diethylformamide, N,N-diethylacetamide ( DMAc), and lactones such as γ-butyrolactone (GBL).

Preferable examples of the solvent for the purpose of improving coatability and the like other than the above include alkyl lactate, 3-methyl-3-methoxybutanol, tetralin, isophorone, and ethylene. Alcohol monoalkyl ether (such as ethylene glycol monobutyl ether (BCS)), diethylene glycol monoalkyl ether (such as diethylene glycol monoethyl ether), ethylene glycol monophenyl ether, triethylene glycol monoalkane a base ether, a propylene glycol monoalkyl ether (such as propylene glycol monobutyl ether), a dialkyl malonate (such as diethyl malonate), a dipropylene glycol monoalkyl ether (such as dipropylene glycol monomethyl ether), and An ester compound of a glycol monoether. Among these compounds, NMP, dimethylimidazolidinone, GBL, BCS, diethylene glycol monoethyl ether, propylene glycol monobutyl ether, and dipropylene glycol monomethyl ether are particularly preferable.

The alignment agent of the present invention may further contain various additives as needed. For example, when it is desired to further improve the coatability, a surfactant which achieves the object may be contained in an appropriate amount; and when further improvement of antistatic property is required, an antistatic agent may be contained in an appropriate amount.

The concentration of the polymer in the alignment agent of the present invention is preferably from 0.1% by weight to 40% by weight, more preferably from 1% by weight to 10% by weight. When the alignment agent is applied to the substrate, when it is necessary to adjust the film thickness, the concentration of the polymer-containing polymer can be adjusted by diluting with a solvent in advance.

The viscosity of the liquid crystal alignment agent of the present invention is different depending on the method of coating, the concentration of polylysine and its derivative, the type of polyamine and the derivative thereof used, and the kind and ratio of the solvent. . For example, in the case of coating with a printing machine, it is 5 mPa‧s to 100 mPa‧s (more preferably 10 mPa‧s 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, there exists a phenomenon that printing unevenness becomes large. In the case of coating by spin coating, it is preferably 5 mPa ‧ to 200 mPa ‧ (more preferably 10 mPa ‧ to 100 mPa ‧ s) In the case of coating with an inkjet coating device, it is preferably 5 mPa ‧ to 50 mPa ‧ (more preferably 5 mPa ‧ to 20 mPa ‧ s) The viscosity of the liquid crystal alignment agent can be measured by a rotational viscosity measurement method, for example, using a rotational viscometer (TVE-20L type manufactured by Toki Sangyo Co., Ltd.) (measurement temperature: 25 ° C).

The alignment film of the present invention can be applied onto a substrate by the method described below, and the solvent can be removed by heating at a relatively low temperature as needed (prepared for calcination); secondly, the solvent removal is further promoted, and the polyamide is further enhanced. Since the acid has an imidization ratio and exhibits the original characteristics of the alignment film, it is obtained by heating at a relatively high temperature (formal calcination). The film obtained as above may also be subjected to a rubbing treatment as needed.

As a coating method of a liquid crystal alignment agent, a spin coating method, a printing method, a dipping method, a dropping method, an inkjet method, etc. are generally known. These methods are also applicable to the present invention.

The liquid crystal display device of the present invention is a liquid crystal display device having a pair of substrates disposed opposite to each other, electrodes formed on one or both surfaces of the opposing faces of the pair of substrates, A liquid crystal alignment film of the present invention formed on a surface facing each other of the pair of substrates, and a liquid crystal layer formed between the pair of substrates.

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 a vapor deposited film of ITO or metal. Further, the electrode may be formed on the entire surface of one of the faces of the substrate, and for example, may be formed into a desired shape that is patterned. The desired shape of the electrode may be, for example, a comb type or a zigzag structure. The electrode may be formed on one of the pair of substrates or may be formed on the two substrates. The form of formation of the electrode differs depending on the type of the liquid crystal display element. For example, in the case of an IPS type liquid crystal display element, an electrode is disposed on one of the pair of substrates; in the case of another liquid crystal display element, Electrodes are disposed on two of the pair of substrates. The liquid crystal alignment film is formed on the substrate or the electrode.

The liquid crystal layer is formed in a form in which a liquid crystal composition is sandwiched by the pair of substrates facing the substrate on which the liquid crystal alignment film is formed. In the formation of the liquid crystal layer, spacers which are appropriately spaced apart may be formed by using fine particles or a resin thin plate or the like between the pair of substrates as needed. A well-known liquid crystal composition can be used for the liquid crystal composition without any particular limitation.

When the alignment film of the present invention forms a liquid crystal display element as a liquid crystal alignment film, properties can be improved for all known liquid crystal compositions. The alignment film of the present invention produced by the above method is particularly effective for improvement of alignment defects of a large-screen display which is difficult to perform rubbing treatment. Such a large-screen display is driven and controlled by a TFT. Further, the liquid crystal composition used in such a TFT-type liquid crystal display device is disclosed in Japanese Patent No. 3086228, Japanese Patent No. 2635435, Japanese Patent Laid-Open No. Hei 5-501735, and Japanese Patent Laid-Open No. Hei 9-255956 It is described in the communique. Therefore, the alignment film of the present invention is preferably used in combination with the liquid crystal composition described in the above documents.

The liquid crystal display element of the present invention exhibits a high black level value or the like when used for IPS, for example, and is excellent in alignment. The value of this black level can be measured in the following manner. That is, the assembled unit is placed on the stage of the microscope in such a manner that the rubbing direction is reversed, and the polarizing element and the analyzer are rotated so as to have a minimum brightness. The light of the fixed brightness is contacted from the back of the unit, and the light transmitted through the unit is sensed by using a photomultiplier mounted on a polarizing microscope, and the amount of the transmitted light is converted into a voltage for measurement (the magnification of the polarizing microscope is 100 times; the eyepiece) 10 times × objective lens 10 times). The smaller the obtained voltage value, the better the black level. In the invention of the present application, it is preferably 1500 μV or less, and more preferably 900 μV or less.

The alignment film of the present invention can impart a good black level and high electrical characteristics to the liquid crystal display device. Such excellent characteristics can be exhibited by using the diamine (1) of the present invention. In this case, the divalent moiety other than the OH or NH ₂ group of the diamine (1) of the present invention may be substituted with any group which does not cause deterioration in characteristics.

The liquid crystal display element of the present invention is also excellent in electrical characteristics related to the reliability of the liquid crystal display element. Such electrical characteristics include voltage holding ratio and ion density. The voltage holding ratio (VHR) is a ratio of a voltage applied to the liquid crystal display element on the liquid crystal display element during a frame period, and indicates a display characteristic of the liquid crystal display element. The liquid crystal display device of the present invention uses a rectangular wave of 5 V and a frequency of 30 Hz, and has a voltage holding ratio of 97.0% or more measured at a temperature of 60 ° C, and a rectangular wave of 5 V and a frequency of 0.3 Hz is used. The voltage holding ratio measured under the temperature condition of ° C is 85.0% or more, and is preferable from the viewpoint of preventing display failure.

The ion density is a transient current generated in addition to the driving of the liquid crystal generated when a voltage is applied to the liquid crystal display element, and indicates the concentration of the ionic impurities contained in the liquid crystal in the liquid crystal display element. The liquid crystal display element of the present invention preferably has an ion density of 300 pC or less from the viewpoint of preventing burn marks of the liquid crystal display element.

[Example]

Hereinafter, the present invention will be described by way of examples and comparative examples.

The evaluation method of the liquid crystal display element in the examples is as follows.

<Pretilt angle measurement>

It was measured according to the crystal rotation method.

<voltage retention rate>

According to the method described in "Water Margin, The 14th Liquid Crystal Symposium Proceedings p78 (1988)", a rectangular wave having a peak value of ±5 V was applied to the cell at 60 °C. The value of the voltage holding ratio is an index indicating how much the applied voltage is maintained after the frame period. If the value is 100%, it means that all charges are held.

<Ion Quantity Measurement in Liquid Crystal (Ion Density)>

The measurement was carried out in accordance with the method described in Applied Physics, Vol. 65, No. 10, and 1065 (1996) using a liquid crystal physical property measurement system 6254 manufactured by Toyo Technologies Co., Ltd. A triangular wave with a frequency of 0.01 Hz was used for measurement at a voltage range of ±10 V and a temperature of 60 ° C (the area of the electrode was 1 cm ² ). If the ion density is large, problems such as burn marks due to ionic impurities are likely to occur. That is, the ion density is a physical property value which is an index for predicting the occurrence of burn marks.

< ¹ H-NMR>

The measurement was carried out using a DRX-500 manufactured by Bruker BioSpin. The samples were all measured in 1 wt% deuterated chloroform.

<weight average molecular weight (Mw)>

The weight average molecular weight (Mw) of the poly-proline in the liquid crystal alignment agent can use DMF containing 0.6 wt% phosphoric acid as an eluent, and use a GF7MHQ column manufactured by Shodex Co., Ltd. at a column temperature of 50 ° C to utilize coagulation. The measurement was carried out by a gel permeation chromatography (GPC) method and determined by polystyrene conversion.

<viscosity>

The measurement was carried out at 25 ° C using a viscometer (manufactured by Toki Sangyo Co., Ltd., TV-22).

[Example 1] Synthesis of Compound (I-5)

<Phase 1: Synthesis of guanamine>

A commercially available 2-amino-2-hydroxymethyl-1,3-propanediol 10.0 g (82.6 mmol) and triethylamine were placed in a 200 mL three-necked flask equipped with a stirring device, a thermometer, a nitrogen introduction tube, and a dropping funnel. 10.0 g (99.1 mmol) was dissolved in 50 mL of N,N-dimethylformamide. The solution was cooled to 5 ° C, and a commercially available 3,5-dinitrobenzimid chloride 15.2 g (66.0 mmol) was slowly added thereto. Next, the reaction liquid was heated to 80 ° C and further stirred for 12 hours. After standing to cool, the solvent was evaporated under reduced pressure to give a crude crystal. The obtained crude crystals were recrystallized from ethanol to obtain 3,5-dinitro-N-((trihydroxymethyl)methyl)benzamide. The yield was 17.7 g and the yield was 85%.

<Phase 2: Reduction of Nitrogen>

In the autoclave reaction tube, the previously obtained 3,5-dinitro-N-((trihydroxymethyl)methyl)benzamide 67.0 g (53.9 mmol) and 5% palladium/carbon powder were placed. At the end of 1.7 g, add 500 mL of ethanol. The inside of the system was made into a hydrogen atmosphere, and the mixture was stirred at a hydrogen pressure of 0.5 mPa at room temperature for 24 hours. The palladium/carbon powder in the reaction liquid was removed, and the solvent was evaporated under reduced pressure to give a crude crystal. The obtained crude crystals were recrystallized from ethanol to obtain 3,5-diamino-N-((trihydroxymethyl)methyl)benzamide. The yield was 12.5 g and the yield was 91%.

¹ H-NMR (ppm): 6.89 (s, -NHCO-, 1H), 6.13 (d, arm. H, 2H), 5.91 (t, arm. H, 1H), 4.91-4.93 (br.s, - OH, -NH ₂ , 7H), 3.58-3.60 (d, -CH ₂ -, 6H).

[Example 2] Synthesis of Compound (1-9)

<Phase 1: Synthesis of guanamine>

A commercially available diethanolamine 10.0 g (95.1 mmol) and triethylamine 11.5 g (114.1 mmol) were placed in a 200 mL three-necked flask equipped with a stirring device, a thermometer, a nitrogen introduction tube, and a dropping funnel, and dissolved in N, N. - Dimethylcarbamide in 100 mL. The solution was cooled to 5 ° C, and 21.9 g (95.1 mmol) of commercially available 3,5-dinitrobenzimid chloride was slowly added thereto. Next, the reaction liquid was heated to 80 ° C, and further stirred for 12 hours. After standing to cool, the solvent was evaporated under reduced pressure to give a crude crystal. The obtained crude crystals were recrystallized from ethanol to obtain N,N-bis(2-hydroxyethyl)-3,5-dinitrobenzamide. The yield was 25.0 g and the yield was 88%.

<Phase 2: Reduction of Nitrogen>

The previously obtained N,N-bis(2-hydroxyethyl)-3,5-dinitrobenzamide 20.0 g (66.8 mmol) and 5% palladium/carbon powder were placed in a reaction tube for autoclave. 2.0 g, add 500 mL of ethanol. The inside of the system was made into a hydrogen atmosphere, and the mixture was stirred at a hydrogen pressure of 0.5 mPa at room temperature for 24 hours. The palladium/carbon powder in the reaction liquid was removed, and the solvent was evaporated under reduced pressure to give a crude crystal. The obtained crude crystals were recrystallized from ethanol to obtain N,N-bis(2-hydroxyethyl)-3,5-diaminobenzamide. The yield was 14.4 g and the yield was 90%.

[Example 3]

<Synthesis of polylysine>

The compound (I-5) 2.2641 g and 4,4'-diaminodiphenylmethane (compound (2-1)) 0.4396 g synthesized according to Example 1 were placed in a three-necked flask equipped with a stirring device and a thermometer. 60 g of N-methyl-2-pyrrolidone (NMP) was added thereto and dissolved. The solution was cooled to 5 ° C, and cyclobutane tetracarboxylic dianhydride (MMDA (A-16)) 1.0871 g and pyromellitic dianhydride (PMDA (A-1)) 1.2091 g were added thereto, and NMP 5 g was added thereto. The reaction solution was warmed to room temperature and stirred for 12 hours. 30 g of ethylene glycol monobutyl ether (BC) was added thereto to obtain a solution having a polyglycine concentration of 5 wt%. The solution has a 25 ° C viscosity of 35 mPa ‧ sec. This solution was used as varnish A. The polyamine acid in the varnish had a weight average molecular weight of 42,000.

[Example 4 to Example 17]

A varnish having a polyglycine concentration of 5 wt% and a viscosity at 25 ° C of 35 mPa ‧ was obtained by the same operation as in Example 3 except that the diamine and the acid dianhydride were changed as shown in Table 1. The monomer composition and the weight average molecular weight of the polymer contained in the prepared varnish were measured and included in Table 1 (in mol% in parentheses).

[Example 18]

<Production of black level measuring unit>

Varnish A 1.0 g was weighed into the sample vial, and NMP/BC = 1/1 (weight ratio) was added to make the total amount 1.67 g. The solution having a polyglycine concentration of about 3 wt% was dropped on a transparent glass substrate, and coated by a spin coating method (2,000 rpm, 15 seconds). After coating, the substrate was heated at 80 ° C for 3 minutes to evaporate the solvent, and then heat-treated in an oven at 230 ° C for 20 minutes. The polyimide film having a thickness of about 70 nm formed by the heat treatment was subjected to rubbing treatment (injection of 0.3 mm, platform feed rate of 60 m/sec, rotation speed of 1000 rpm, alignment cloth of YA-18-R) (Rayon)). The alignment film was subjected to ultrasonic cleaning in ultrapure water for 5 minutes, and then dried in an oven at 120 ° C for 30 minutes. The surface on which the alignment film was formed was placed on the inner side, and the two glass substrates were opposed to each other so that the rubbing direction was reversed, and then sealed with an epoxy hardener containing a 25 μm caulk to form a gap of 25 μm. Anti-parallel cell. The liquid crystal composition A described below was injected into the unit, and the injection port was sealed with a photocurable sealant. Next, heat treatment was performed at 110 ° C for 30 minutes to prepare a liquid crystal display element. The black level was measured using the obtained unit, and the measured value of the voltage was 1,070 μV.

<Liquid crystal composition A>

[化76]

[Example 19 to Example 32]

A black level measuring unit was produced by the method described in Example 18 except that the varnish A was replaced with the varnish B to the varnish O. Among them, the unit produced by using the varnish H was not subjected to a rubbing treatment on the polyimide film to inject the liquid crystal composition B. The measurement results of the black levels of these examples are shown in Table 2 together with the results of Example 18.

<Liquid crystal composition B>

[化77]

A good black level was observed in all of the cells produced.

[Example 33]

<Preparation of pretilt angle and electrical characteristic measurement unit>

1.0 g of varnish A was weighed into the sample vial, and NMP/BC = 1/1 (weight ratio) was added to make the total amount 1.67 g. The solution having a polyglycine concentration of about 3 wt% was dropped on a transparent glass substrate, and coated by a spin coating method (2,000 rpm, 15 seconds). After coating, the substrate was heated at 80 ° C for 3 minutes to evaporate the solvent, and then heat-treated in an oven at 230 ° C for 20 minutes. The polyimide film having a film thickness of about 70 nm formed by the heat treatment was subjected to rubbing treatment (injection of 0.3 mm, platform feed rate of 60 m/s, rotation speed of 1000 rpm, alignment cloth of YA-18-R) (Rayon)). The alignment film was subjected to ultrasonic cleaning in ultrapure water for 5 minutes, and then dried in an oven at 120 ° C for 30 minutes. A 7 μm caulk was spread on one of the alignment films. The alignment film surface of the other substrate was placed on the inner side, and the rubbing direction was reversed and arranged in the opposite direction, and then sealed with an epoxy curing agent to prepare an antiparallel unit having a pitch of 7 μm. The liquid crystal composition A was injected into the unit, and the injection port was sealed with a photocurable sealant. Next, heat treatment was performed at 110 ° C for 30 minutes to prepare a liquid crystal display element. The cell has a voltage holding ratio of 98.5% (30 Hz) and 90.5% (0.3 Hz), a pretilt angle of 1.2°, and an ion density of 85 pC.

[Example 34 to Example 47]

An electric property measuring unit was produced by the method described in Example 33 except that the varnish A was replaced with the varnish B to the varnish O. Among them, the unit produced by using the varnish H was not subjected to a rubbing treatment on the polyimide film to inject the liquid crystal composition B. The electrical characteristics of these examples and the measurement results of the pretilt angle are shown in Table 3 together with the results of Example 33.

Good VHR and ion density were observed in all of the cells produced.

[Example 48 to Example 62]

<Confirmation of the effect of the epoxy compound additive>

1.0 g of varnish A to varnish O was weighed into the sample vial, and NMP/BC = 1/1 (weight ratio) was added to make the total amount 1.67 g. 0.01 g of any of the epoxy additive (E1) to the epoxy additive (E5) was added thereto and stirred well. The black level measuring unit and the electric characteristic measuring unit were produced in accordance with the method described in Example 18. Among them, the unit produced by using the varnish H was not subjected to a rubbing treatment on the polyimide film to inject the liquid crystal composition B. Black level measurement, VHR measurement (30 Hz and 0.3 Hz), ion density measurement, and pretilt angle measurement were performed using the fabricated cell. The measurement results are shown in Table 4.

It was confirmed that the addition of the epoxy compound did not lower the VHR and the ion density, and the pretilt angle did not change, and the black level could be further increased.

[Example 63 to Example 77]

<Confirmation of the effect of the oxazoline compound additive>

1.0 g of varnish A to varnish O was weighed into the sample vial, and NMP/BC = 1/1 (weight ratio) was added to make the total amount 1.67 g. 0.01 g of the oxazoline additive (F1) was added thereto and stirred well. The black level measuring unit and the electric characteristic measuring unit were produced in accordance with the method described in Example 18. Among them, the unit produced by using the varnish H was not subjected to a rubbing treatment on the polyimide film to inject the liquid crystal composition B. Black level measurement, VHR measurement (30 Hz and 0.3 Hz), ion density measurement, and pretilt angle measurement were performed using the fabricated cell. The measurement results are shown in Table 5.

It was confirmed that by adding the oxazoline compound, the VHR and the ion density were not lowered, and the pretilt angle was not changed, and the black level was further improved.

[Comparative Example 1] Synthesis of Compound C1

<Phase 1: Synthesis of guanamine>

A commercially available 3-amino-3-ethyl-n-pentane 10.0 g (86.8 mmol) and triethylamine 13.2 g were placed in a 200 mL three-necked flask equipped with a stirring device, a thermometer, a nitrogen introduction tube, and a dropping funnel. 130.2 mmol) was dissolved in 50 mL of N,N-dimethylformamide. The solution was cooled to 5 ° C, and 18.0 g (78.1 mmol) of commercially available 3,5-dinitrobenzimid chloride was slowly added thereto. Next, the reaction liquid was heated to 80 ° C and stirred for 12 hours. After standing to cool, the solvent was evaporated under reduced pressure to give a crude crystal. The obtained crude crystals were recrystallized from toluene to obtain 3,5-dinitro-N-((triethyl)methyl)benzamide. The yield was 19.6 g and the yield was 81%.

<Phase 2: Reduction of Nitrogen>

19.0 g (61.4 mmol) of the previously obtained 3,5-dinitro-N-((triethyl)methyl)benzamide and 5% palladium/carbon powder were placed in a reaction tube for autoclave. Add 500 mL of ethanol. The inside of the system was brought to a hydrogen atmosphere, and stirred at a hydrogen pressure of 0.5 mPa at room temperature for 24 hours. Remove the opposite The palladium/carbon powder in the solution was distilled off under reduced pressure to obtain a crude crystal. The obtained crude crystals were recrystallized from ethanol to obtain 3,5-diamino-N-((triethyl)methyl)benzamide. The yield was 13.6 g and the yield was 89%.

¹ H-NMR (ppm): 7.42 (s, -NHCO-, 1H), 6.45 (d, arm. H, 2H), 5.90 (t, arm. H, 1H), 4.78 (br.s, -NH _{2 )} , 4H), 1.41-1.45 (q, -CH ₂ -, 6H), 1.04 (t, -CH ₃ , 9H).

[Comparative Example 2 to Comparative Example 4]

<Modulation of polylysine>

Based on the method described in Example 2, varnish X to varnish Z having a polyglycine concentration of 5 wt% and a viscosity of 35 mPa ‧ was obtained. The prepared varnish is shown in Table 6 (mol% in brackets).

[Comparative Example 5 to Comparative Example 7]

<Black level measurement and electrical characteristic measurement>

The black level measuring unit and the electric characteristic measuring unit were produced and measured according to the method described in Example 18. The measurement results are shown in Table 7.

It is understood that the black display characteristics of the unit composed of the alignment agent using diamine C1 as a raw material are not sufficient.

[Comparative Example 8 to Comparative Example 10]

<Confirmation of the effect of the additive>

1.0 g of the varnish Z obtained in Comparative Example 7 was weighed in a sample bottle, and NMP/BC = 1/1 (weight ratio) was added to make a total amount of 1.67 g. Any one of 0.01 g of an epoxy compound or an oxazoline compound was added thereto and stirred well. The black level measuring unit and the electric characteristic measuring unit were produced by the method described in Example 18, and the measurement was performed. The compound to be added and the measurement results are shown in Table 8.

Even with the addition of various compounds, no improvement in black display was observed. Moreover, the fluctuation of the pretilt angle is confirmed in a part of the unit.

Claims (19)

a diamine represented by the formula (I). Where R is represented by (a), (b) or (c), (wherein R ⁰ is hydrogen or methyl). The diamine of claim 1, wherein R ⁰ is hydrogen. The diamine according to claim 1 or 2, wherein in the formula (I), the two amino groups are substituted for the 3-position and the 5-position, respectively, with respect to the substituent represented by R. A poly-proline and a derivative thereof, which is at least one of the diamine represented by the formula (I) and the tetracarboxylic dianhydride according to any one of the above claims 1 to 3. The reaction is obtained. A poly-proline and a derivative thereof, which are at least one of the diamines represented by the formula (I) and other diamines (D2) according to any one of the above claims 1 to 3. a mixture of tetracarboxylic dianhydride Income. The polyamic acid as described in claim 4 or 5, wherein the tetracarboxylic dianhydride is selected from the group consisting of the following formula (DA-20) to formula (DA-32). One or more groups, In the formula (DA-20), G ⁵ is a single bond, an alkylene group having a carbon number of 1 to 12, a 1,4-phenylene group or a 1,4-cyclohexylene group; and X ^{10 is} independently a single bond or CH ₂ ; Moreover, G ^{6 is} independently CH or N, and when G ⁶ is N, G ⁵ is not a single bond or CH ₂ , and X ¹⁰ is not a single bond; In the formula (DA-21), R ^{14 is} independently hydrogen, methyl, ethyl or phenyl; In the formula (DA-22), the ring A ⁶ is a cyclohexane ring or a benzene ring; In the formula (DA-23), G ⁷ is a single bond, an alkylene group having a carbon number of 1 to 10, 1,4-phenylene group, O, CO, S, SO ₂ , C(CH ₃ ) ₂ or C(CF ₃ ) ₂ ; Moreover, ring A ^{7 is} independently a cyclohexane ring or a benzene ring; [Chemical 7] In the formula (DA-24), R ¹⁵ is hydrogen or methyl; In the formula (DA-25), X ¹⁰ is a single bond or CH ₂ ; X ^{11 is} independently CH ₂ , CH ₂ CH ₂ or CH=CH; and, v is 1 or 2; [Chemical 9] In formula (DA-26), X ¹⁰ is a single bond or CH ₂ ; In the formula (DA-27), R ¹⁴ is hydrogen, methyl, ethyl or phenyl; ring A ⁸ is a cyclohexane ring, a cyclohexene ring or a benzene ring; and, X ¹² is a single bond, CH ₂ Or CH(CH ₃ ); [Chemical 11] In the formula (DA-28), w2 and w3 are 0 or 1, and when w2=1, w3=1; In the formula (DA-30), X ^{13 is} independently an alkyl group having 2 to 6 carbon atoms; and, Ph represents a phenyl group; In the formula (DA-32), X ¹⁴ independently represents a single bond or CH ₂ . The poly-proline and the derivative thereof according to the fifth aspect of the invention, wherein the other diamine (D2) is a diamine represented by the following formula (1-1) to formula (4), [Chem. 16] In the formula (1-1), b is 0 or 1; any hydrogen in the cyclohexylene group may also be substituted by a methyl group; in the formula (1-2), W ¹ is -CH ₂ - or -NH- ; Here, X ¹ is a single bond or an alkylene group having a carbon number of 1 to 10; any -CH ₂ - of the alkylene group may also be -O-, -S-, -NH-, -N(CH) ₃ )-, -C(CH ₃ ) ₂ -, -C(CF ₃ ) ₂ -, -CO-, -SO ₂ -, 1,3-phenylene, 1,4-phenylene or pyridazine- 1,4-diyl substitution; [Chem. 18] In the formula (3), X ² is a single bond, -O-, -COO-, -OCO- or an alkylene group having a carbon number of 1 to 6; and R ¹ is an alkyl group having a carbon number of 3 to 30 or a formula (a) the group represented; in the formula (a), X ³ and X ^{4 are} independently a single bond or an alkylene group having 1 to 4 carbon atoms; and ring B and ring C are independently a 1,4-phenylene group. Or 1,4-cyclohexylene; R ² and R ^{3 are} independently fluoro or methyl, and f and g are independently 0, 1 or 2; c, d and e are independently 0 or 1, and c, d and e The total is 1 to 3; R ⁴ is an alkyl group having 1 to 30 carbon atoms, an alkoxy group having 1 to 30 carbon atoms, an alkoxyalkyl group having 2 to 30 carbon atoms or a cholesteryl group. In the alkyl, alkoxy and alkoxyalkyl groups, any hydrogen may also be substituted by fluorine; [Chem. 19] Here, X ^{5 is} independently -O- or an alkylene group having a carbon number of 1 to 6; j is independently 0 or 1; R ⁵ is hydrogen, an alkyl group having 2 to 12 carbon atoms or a carbon number of 2 to 12 Alkoxy; ring T is 1,4-phenylene or 1,4-cyclohexylene; X ⁶ is a single bond or an alkylene group having 1 to 3 carbon atoms; h is 0 or 1. The polyamic acid as described in claim 5, wherein the other diamine (D2) is at least one selected from the group consisting of the following compounds, [Chem. 20] (wherein R ¹¹ is -CH ₂ -, -O- or a linear alkylene group having a carbon number of 1 to 4, R ¹² is hydrogen or CH ₃ , and R ¹³ is a linear subgroup having 2 to 4 carbon atoms; An alkyl group, R ¹⁴ is a linear alkylene group having 1 to 8 carbon atoms, R ^{15 is} independently -CH ₂ -, -(CH ₂ ) ₂ - or -NH-, and R ¹⁶ is a hydrogen atom or a carbon number of 1 A linear alkylene group of ~10, R ¹⁷ is a hydrogen atom or a linear alkylene group having 1 to 16 carbon atoms, and R ^{18 is} independently -CH ₂ -, -(CH ₂ ) ₂ - or -O-). A composition comprising at least one polymer selected from the group consisting of polylysines and derivatives thereof according to any one of claims 4 to 8. A liquid crystal alignment agent which is composed of a composition containing at least one polymer selected from the group consisting of polyamino acids and derivatives thereof according to any one of claims 4 to 8. The liquid crystal alignment agent according to claim 10, which comprises the epoxy compound (E). The liquid crystal alignment agent according to claim 11, wherein the epoxy compound (E) is one or more selected from the group consisting of compounds represented by the following formulas (E1) to (E6), (where n is an integer from 1 to 10). The liquid crystal alignment agent according to claim 10, which comprises an oxazoline compound (F). The liquid crystal alignment agent according to claim 13, wherein the oxazoline compound (F) is a compound represented by the following formula (F1), The liquid crystal alignment agent according to claim 10, which comprises a bisallyl nadic ylidene imine compound (G). The bisallyl nadic quinone imine compound (G) is a group consisting of a compound represented by the following formula (G1) and formula (G2), in the liquid crystal alignment agent according to the fifteenth aspect of the invention. One or more types, . The liquid crystal alignment agent according to claim 10, which comprises a compound selected from the group consisting of the epoxy compound (E) represented by the following formula (E1) to the formula (E6), and the oxazoline compound (F) is as follows The compound represented by the formula (F1) and the bisallyl nadic ylidene imine compound (G) are one or more groups of the compounds represented by the following formula (G1) and formula (G2), (where n is an integer from 1 to 10) . A liquid crystal alignment film which is patented in the scope of claim 10 The liquid crystal alignment agent according to any one of item 17, wherein the liquid crystal alignment agent is formed. A liquid crystal display element comprising a liquid crystal alignment film comprising the liquid crystal alignment agent according to any one of claims 10 to 17.