JP5892330B2 - Liquid crystal alignment agent - Google Patents

Description

  The present invention relates to a liquid crystal aligning agent. More specifically, the present invention relates to a liquid crystal aligning agent that has a high degree of liquid crystal alignment control power, does not cause display defects due to insufficient alignment control power, and can provide a liquid crystal display device with excellent electrical characteristics.

In the liquid crystal display element, a liquid crystal alignment film is provided on the substrate surface in order to align liquid crystal molecules in a predetermined direction with respect to the substrate surface. This liquid crystal alignment film is usually formed by a method (rubbing method) in which the surface of the organic film formed on the substrate surface is rubbed in one direction with a cloth material such as rayon. However, if the liquid crystal alignment film is formed by rubbing treatment, dust and static electricity are likely to be generated during the rubbing process, so that dust adheres to the alignment film surface and causes display defects. In the case of a substrate having elements, there is also a problem that circuit yield of the TFT elements occurs due to the generated static electricity and causes a reduction in product yield. Therefore, as another means of aligning the liquid crystal in the liquid crystal cell, a photo-alignment method has been proposed in which a liquid-sensitive organic thin film formed on the substrate surface is irradiated with polarized or non-polarized radiation to impart liquid crystal alignment ability. (See Patent Documents 1 to 4).
As the liquid crystal display element, in addition to a liquid crystal display element having a vertical electric field type liquid crystal cell such as a TN type, an STN type, or a VA type, an IPS (In-Plane Switching) type or an FFS (Fringe Field Switching) type or the like 2. Description of the Related Art A lateral electric field type liquid crystal display element is known in which electrodes are formed only on the side of a pair of substrates arranged to generate an electric field in a direction parallel to the substrate (Patent Documents 5 to 7). This horizontal electric field type liquid crystal display element has wider viewing angle characteristics than a vertical electric field type liquid crystal display element, and can display a high quality. Since the horizontal electric field type liquid crystal display element responds to the electric field only in the direction in which the liquid crystal molecules are parallel to the substrate, the change in the refractive index in the major axis direction of the liquid crystal molecules is not a problem. There is little change in the contrast and the contrast of the displayed color, so that high-quality display is possible regardless of the viewing angle.

Also in a horizontal electric field type liquid crystal display element, in order to avoid the drawbacks of the rubbing method described above when providing liquid crystal alignment properties to the liquid crystal alignment film, it is desirable to use a photo alignment method. However, the liquid crystal aligning agent applicable to the photo-alignment method may not yet have sufficient liquid crystal alignment regulating power. When such a liquid crystal alignment film is used, a display defect called discrimination may be seen.
In the case of a liquid crystal display element using a spacer of a type that disperses beads having a small particle size, a phenomenon occurs in which only the bead portion is whitened during black display. Since the beads have a small particle size on the order of μm, there is no problem in viewing as long as the white spots are present. However, in some cases, white lines connecting the adjacent beads may be seen in addition to the white portions of the beads. This white line should not be present on the screen because the viewer can clearly recognize it as a display defect. In this specification, the discrimination means such a display defect (a linear white defect). This display defect is believed to be caused by a lack of liquid crystal alignment regulating force of the alignment film.
Discrimination was not a big problem at the level of image resolution in the analog broadcasting era.
However, in recent years, imaging technology and moving image transmission technology have made dramatic progress, and so-called high-definition broadcasting has been digitally distributed in home-use television broadcasting. Along with this, high definition of liquid crystal display elements is progressing. Since the liquid crystal alignment film used in the high-definition element requires a high degree of liquid crystal alignment control, the above-mentioned liquid crystal alignment film by the photo-alignment method is applied to the lateral electric field type high-definition liquid crystal display element. This discrimination became obvious.

JP 2003-307736 A JP 2004-163646 A JP 2002-250924 A JP 2004-83810 A U.S. Pat. No. 5,928,733 JP 56-91277 A JP 2008-46184 A JP 2010-97188 A

The present invention has been made to overcome the above-described current situation.
The object of the present invention is to display the advantageous effect of the transverse electric field method by the photo-alignment method, and has a high degree of liquid crystal alignment control power, and display defects (particularly linear white defects) due to insufficient alignment control power. The liquid crystal aligning agent which can give the liquid crystal display element which is excellent in an electrical property is not provided.

According to the present invention, the above objects and advantages of the present invention are:
At least one selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic dianhydride and a diamine containing a compound represented by the formula (A-1) described later and an imidized polymer thereof, It is achieved by a liquid crystal aligning agent characterized by containing a polymer having a structure represented by (A).

(In formula (A), X ¹ is an oxygen atom, a sulfur atom, —SO ₂ —, —NH— or a methylene group;
R ¹ and R ² are each independently a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a halogenated alkyl group having 1 to 10 carbon atoms, carbon A halogenated alkoxy group of formula 1 to 10 or the following formula (R ¹² )
^{X-R-Z- + (R} 12)
(Wherein ^{(R 12),} X is a cyano group or a nitro group, R is a methylene group or an alkoxy group having 2 to 6 carbon atoms, Z is a single bond, an oxygen atom, a sulfur atom, _-SO 2 -, -NH-, -COO- or -OCO-, and "+" represents a bond.)
A group represented by
i is an integer from 0 to 5;
j is an integer of 0 to 4, and “*” represents a bond. )

The liquid crystal aligning agent of this invention can form the liquid crystal aligning film for using for the liquid crystal display element of a horizontal electric field system which has high liquid crystal alignment control power by the photo-alignment method. The liquid crystal alignment film formed from the liquid crystal alignment agent of the present invention exhibits the advantageous effect of the transverse electric field method, does not cause display defects due to insufficient alignment regulating force, and provides a liquid crystal display element with excellent electrical characteristics. be able to.
The liquid crystal aligning agent of this invention is especially suitable for manufacture of the liquid crystal display element of a horizontal electric field system for displaying a high-definition image.

Hereinafter, the present invention will be described in detail. The liquid crystal aligning agent of the present invention contains a polymer having a structure represented by the above formula (A) (hereinafter referred to as “specific polymer”).
X ¹ in the above formula (A) is preferably an oxygen atom.
R ¹ and R ² are each independently preferably a fluorine atom, a cyano group, a methyl group, a methoxy group or a 3-cyanopropoxy group, and are a fluorine atom, a cyano group, a methyl group or a 3-cyanopropoxy group. It is more preferable.
i is preferably 0 or 1, and j is preferably 0.
The content ratio of the structure represented by the above formula (A) in the specific polymer is preferably 1.0 × 10 ⁻⁴ mol / g or more, and 3.0 × 10 ^{−4 to} 2.0 × 10 ^{−. 3} mol / g is more preferable, and 5.0 × 10 ^{−4 to} 2.0 × 10 ⁻³ mol / g is more preferable.
Specific polymers in the present invention include, for example, polyamic acid, imidized polymer of polyamic acid, polyamic acid ester, polyorganosiloxane, polyester, polyamide, polysiloxane, cellulose derivative, polyacetal, polystyrene or derivatives thereof, poly (styrene-phenyl) Maleimide) or a derivative thereof, poly (meth) acrylate, a reaction product of a polyfunctional carboxylic acid and a polyfunctional epoxy compound, and the like. Of these, at least one selected from the group consisting of polyamic acids and imidized polymers thereof is preferable.

The polyamic acid which is a specific polymer in the present invention is obtained by reacting, for example, a tetracarboxylic dianhydride including a tetracarboxylic dianhydride having a structure represented by the above formula (A) with a diamine: It can be synthesized by reacting an acid dianhydride with a diamine containing a diamine having a structure represented by the above formula (A);
The imidized polymer of polyamic acid which is a specific polymer in the present invention can be synthesized, for example, by dehydrating and ring-closing the polyamic acid.
The specific polymer in the present invention includes a polyamic acid obtained by reacting a tetracarboxylic dianhydride and a diamine containing a diamine having a structure represented by the above formula (A), and an imidized polymer of the polyamic acid. Most preferably, it is at least one selected from the group consisting of:

Examples of the tetracarboxylic acid include aliphatic tetracarboxylic dianhydrides, alicyclic tetracarboxylic dianhydrides, aromatic tetracarboxylic dianhydrides, and the like. Specific examples of these include aliphatic tetracarboxylic dianhydrides such as butane tetracarboxylic dianhydride;
Examples of the alicyclic tetracarboxylic dianhydride include 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,4,5- Cyclohexanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2 , 5-Dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2) , 5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 3,5,6-tricarboxy-2-carboxymethylnorbornane-2; 3,5; Anhydride, 2, 4 6,8-tetracarboxybicyclo [3.3.0] octane-2; 4,6; 8-dianhydride, 3-oxabicyclo [3.2.1] octane-2,4-dione-6-spiro -3 ′-(tetrahydrofuran-2 ′, 5′-dione), 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, 4 , 9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane-3,5,8,10-tetraone;
As the aromatic tetracarboxylic dianhydride, for example, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, pyromellitic dianhydride, etc. can be mentioned,
The tetracarboxylic dianhydride described in Patent Document 8 (Japanese Patent Laid-Open No. 2010-97188) can be used.

The tetracarboxylic dianhydride used for synthesizing the specific polymer in the present invention is at least one selected from the group consisting of alicyclic tetracarboxylic dianhydrides and aromatic tetracarboxylics. In particular, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic acid Dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo -3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (te Lahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 3,5,6-tricarboxy-2-carboxymethylnorbornane-2; 3,5; 6-dianhydride, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2; 4,6; 8-dianhydride, 3,3 ′, 4,4′-benzophenone tetra It is preferable to include at least one selected from the group consisting of carboxylic dianhydride and pyromellitic dianhydride (hereinafter referred to as “specific tetracarboxylic dianhydride”). The tetracarboxylic dianhydride used for synthesizing the specific polymer in the present invention contains the above-mentioned specific tetracarboxylic dianhydride in an amount of 80 mol% or more based on the total tetracarboxylic dianhydride. It is preferable that it is 90 mol% or more.
The tetracarboxylic dianhydride used for synthesizing the polyamic acid is most preferably composed of only a specific tetracarboxylic dianhydride.

Diamine need use to synthesize a particular polymer in the present invention contains a diamine having the structure represented by the above formula (A).
Examples of the diamine having the structure represented by the above formula (A) include the following formula (A-1):

(In formula (A-1), R ¹ , R ² , X ¹ , i and j each have the same meaning as in formula (A) above,
Z ¹ is a methylene group, an alkylene group having 2 to 10 carbon atoms, an alkenylene group having 2 to 10 carbon atoms, a cyclohexylene group or a phenylene group,
X ² is a single bond, an oxygen atom, a sulfur atom, —COO—, —OCO—, —CO—, —SO ₂ — or an amide bond, and k is an integer of 0 to 5. )
A compound represented by the following formula

And the like, and the like.
Diamines, as used herein, is a diamine containing a compound represented by the above formula (A-1). In the above formula (A-1), the two amino groups bonded to the benzene ring are preferably in the 2,4-position or 3,5-position with respect to other groups.
Specific examples of the compound represented by the formula (A-1) include compounds represented by the following formulas, for example.

As the diamine having the structure represented by the formula (A), a compound represented by the formula (A-1) is preferable.
The compound represented by the above formula (A-1) can be synthesized by appropriately combining conventional methods of organic compound synthesis. For example, it can be synthesized by the following method;
The compound in which k in the above formula (A-1) is 1 or more and X ² is an oxygen atom is, for example, first represented by the following formula:

(In the above formula, R ¹ , R ² , X ¹ , i and j have the same meaning as in the above formula (A-1), and X is a halogen atom.)
A substituted cinnamic acid having a desired substituent is obtained by a Heck reaction between the compound represented by formula (II) and acrylic acid. Subsequently, this substituted cinnamic acid is converted into HO— (Z ¹ —X ² ) _k —H (wherein Z ¹ , X ² and k have the same meanings as in the above formula (A-1)). Can be obtained by performing a dehydrofluorination condensation reaction with dinitrofluorobenzene, and further hydrogenating the nitro group with an appropriate hydrogenation catalyst system.
The compound in which k in the above formula (A-1) is 1 or more and X ² is a single bond is obtained by, for example, replacing the substituted cinnamic acid obtained in the same manner as described above with the group HO— (Z ¹ -X ² ) _k —. Can be obtained by hydrogenating the nitro group with a suitable hydrogenation catalyst system.
The compound in which k in the above formula (A-1) is 1 or more and X ² is —OCO— (wherein the carbon atom is on the diaminobenzene side) is, for example, a substituted cinnamic acid obtained in the same manner as described above. Is a diol compound represented by HO- (Z ¹ -X ² ) _k -H (wherein Z ¹ , X ² and k have the same meanings as in the above formula (A-1)). Then, an esterification reaction with a dinitrobenzoic acid halide is carried out, and further a nitro group is hydrogenated with an appropriate hydrogenation catalyst system.

As the diamine used for synthesizing the specific polymer in the present invention, only the compound represented by the above formula (A-1) may be used, or another diamine may be used in combination therewith.
Examples of other diamines that can be used here include aliphatic diamines, alicyclic diamines, aromatic diamines (excluding compounds represented by the above formula (A-1)), diaminoorganosiloxanes, and the like. Can be mentioned. Specific examples thereof include aliphatic diamines such as 1,1-metaxylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine and the like;
Examples of alicyclic diamines include 1,4-diaminocyclohexane, 4,4′-methylenebis (cyclohexylamine), 1,3-bis (aminomethyl) cyclohexane and the like;

Examples of aromatic diamines include p-phenylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl sulfide, 1,5-diaminonaphthalene, 2,2′-dimethyl-4,4′-diaminobiphenyl, 4,4′-diamino-2,2′-bis (trifluoromethyl) biphenyl, 2,7-diaminofluorene, 4,4′-diaminodiphenyl ether, 2,2-bis [4- (4-aminophenoxy) phenyl ] Propane, 9,9-bis (4-aminophenyl) fluorene, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane 4,4 ′-(p-phenylenediisopropylidene) bisaniline, 4,4 ′-(m-phenylenediisopropylene Riden) bisaniline, 1,4-bis (4-aminophenoxy) benzene, 4,4′-bis (4-aminophenoxy) biphenyl, 2,6-diaminopyridine, 3,4-diaminopyridine, 2,4-diamino Pyrimidine, 3,6-diaminoacridine, 3,6-diaminocarbazole, N-methyl-3,6-diaminocarbazole, N-ethyl-3,6-diaminocarbazole, N-phenyl-3,6-diaminocarbazole, N , N′-bis (4-aminophenyl) -benzidine, N, N′-bis (4-aminophenyl) -N, N′-dimethylbenzidine and the like;
Examples of the diaminoorganosiloxane include 1,3-bis (3-aminopropyl) -tetramethyldisiloxane, respectively.
Diamines described in Patent Document 8 (Japanese Patent Laid-Open No. 2010-97188) can be used.
The diamine used for synthesizing the polyamic acid preferably contains the compound represented by the above formula (A-1) in an amount of 10 mol% or more, preferably 30 mol% or more based on the total amount of the diamine. More preferably, it is preferable to contain 50 mol% or more.

The ratio of tetracarboxylic dianhydride and diamine used for synthesizing the polyamic acid is such that the acid anhydride group of tetracarboxylic dianhydride is 0.2 to 2 with respect to 1 equivalent of amino group contained in the diamine. It is preferable to set it as the ratio used as an equivalent, and it is more preferable to set it as 0.3-1.2 equivalent.
The synthesis reaction of the polyamic acid is preferably performed in an organic solvent. Examples of the organic solvent include aprotic such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, dimethyl sulfoxide, γ-butyrolactone, tetramethylurea, hexamethylphosphortriamide and the like. Polar solvent;
phenol derivatives such as m-cresol, xylenol, halogenated phenol;
Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone;
Esters such as ethyl lactate, butyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, diethyl oxalate, diethyl malonate, isoamylpropionate, isoamyl isobutyrate;

Diisopentyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether, ethylene glycol-i-propyl ether, ethylene glycol-n-butyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether Ethers such as diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, tetrahydrofuran;
Halogenated hydrocarbons such as dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, o-dichlorobenzene;
Examples thereof include hydrocarbons such as benzene, toluene and xylene, and one or more selected from these can be used.
The reaction temperature of the polyamic acid synthesis reaction is preferably -20 to 150 ° C, more preferably 0 to 100 ° C. The reaction time is preferably 0.5 to 24 hours, and more preferably 2 to 12 hours.

The imidized polymer of polyamic acid which is a specific polymer in the present invention can be synthesized by dehydrating and ring-closing the polyamic acid synthesized as described above. At this time, it may be a fully imidized product in which all of the amic acid structure possessed by the polyamic acid is dehydrated and cyclized, or only a part of the amic acid structure is dehydrated and cyclized. It may be a compound.
The polyamic acid is preferably dehydrated and cyclized by heating the polyamic acid, or by dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydrating ring-closing catalyst to this solution, and heating as necessary. Is called. Of these, the latter method is particularly preferred.
In the method of adding a dehydrating agent and a dehydrating ring-closing catalyst to the polyamic acid solution, for example, an acid anhydride such as acetic anhydride, propionic anhydride, or trifluoroacetic anhydride can be used as the dehydrating agent. It is preferable that the usage-amount of a dehydrating agent shall be 0.01-20 mol with respect to 1 mol of the amic acid structure which a polyamic acid has. As the dehydration ring closure catalyst, for example, tertiary amines such as pyridine, collidine, lutidine, and triethylamine can be used. The use ratio of the dehydration ring-closing catalyst is preferably 0.01 to 10 mol with respect to 1 mol of the dehydrating agent to be used. As the organic solvent used for the dehydration ring closure reaction, the organic solvents exemplified above as those used for the synthesis of polyamic acid can be used.
The reaction temperature of the dehydration ring closure reaction is preferably 0 to 180 ° C, more preferably 10 to 150 ° C. The reaction time is preferably 1.0 to 120 hours, more preferably 2.0 to 30 hours.

The polyamic acid or imidized polymer obtained as described above preferably has a solution viscosity of 20 to 800 mPa · s, when it is made into a solution having a concentration of 10% by weight, and preferably 30 to 500 mPa · s. More preferably, it has a solution viscosity of s. The solution viscosity (mPa · s) of this polymer is about 10% by weight of the polymer solution prepared using a good solvent for these polymers (for example, γ-butyrolactone, N-methyl-2-pyrrolidone, etc.). It is a value measured at 25 ° C. using an E-type rotational viscometer.
The weight average molecular weight (Mw) in terms of polystyrene measured by gel permeation chromatography (GPC) for the polyamic acid and its imidized polymer is preferably 1,000 to 500,000, preferably 2,000 to 300. Is more preferable. The ratio (Mw / Mn) between this Mw and polystyrene-reduced number average molecular weight (Mn) measured by gel permeation chromatography (GPC) is preferably 15 or less, and more preferably 10 or less. By being in such a molecular weight range, the stability of the liquid crystal aligning agent can be increased, and good alignment in the obtained liquid crystal display element can be ensured.

<Other ingredients>
Although the liquid crystal aligning agent of this invention contains the above specific polymers as an essential component, it may contain the other component as needed. Examples of other components include other polymers other than the specific polymer, compounds having at least one epoxy group in the molecule (hereinafter also referred to as “epoxy compound”), functional silane compounds, and the like.

[Other polymers]
These other polymers can be used to improve solution and electrical properties. Such other polymers are polymers having no structure represented by the above formula (A), such as polyamic acid, imidized polymer of polyamic acid, polyamic acid ester, polyester, polyamide, polysiloxane, cellulose derivative. , Polyacetal, polystyrene and derivatives thereof, poly (styrene-phenylmaleimide) and derivatives thereof, and poly (meth) acrylate, and has a structure represented by the above formula (I) There can be no polymer.
The proportion of the other polymer used is preferably 50% by weight or less, preferably 40% by weight or less, based on the total of the polymers (the total of the specific polymer and other polymers; the same shall apply hereinafter). More preferably, it is more preferably 30% by weight or less.

[Epoxy compound]
Examples of the epoxy compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, neopentyl glycol diglycidyl ether, and 1,6-hexane. Diol diglycidyl ether, glycerin diglycidyl ether, trimethylolpropane triglycidyl ether, 2,2-dibromoneopentyl glycol diglycidyl ether, N, N, N ′, N′-tetraglycidyl-m-xylenediamine, 1,3 -Bis (N, N-diglycidylaminomethyl) cyclohexane, N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylme N, N-diglycidyl-benzylamine, N, N-diglycidyl-aminomethylcyclohexane, N, N-diglycidyl-cyclohexylamine, etc., and using one or more selected from these Can do.
The use ratio of these epoxy compounds is preferably 40 parts by weight or less, more preferably 0.1 to 30 parts by weight with respect to 100 parts by weight of the total amount of the polymer.

[Functional silane compounds]
Examples of the functional silane compound include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-aminopropyltrimethoxysilane, 2-aminopropyltriethoxysilane, N- (2-aminoethyl)- 3-aminopropyltrimethoxysilane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane, N-ethoxycarbonyl-3-aminopropyl Trimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N-trimethoxysilylpropyltriethylenetriamine, 10-trimethoxysilyl-1,4 7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9-trimethoxysilyl-3,6-diazanonyl acetate, 9- Triethoxysilyl-3,6-diazanonyl acetate, methyl 9-trimethoxysilyl-3,6-diazananoate, methyl 9-triethoxysilyl-3,6-diazananoate, N-benzyl-3-aminopropyltri Methoxysilane, N-benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-phenyl-3-aminopropyltriethoxysilane, glycidoxymethyltrimethoxysilane, glycidoxy Methyltriethoxysilane, 2-glycidoxyethyltrimeth Sisilane, 2-glycidoxyethyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, etc. can be used, and one or more selected from these can be used can do.
The use ratio of these functional silane compounds is preferably 2 parts by weight or less, more preferably 0.02 to 0.2 parts by weight with respect to 100 parts by weight of the total amount of the polymer.

<Preparation of liquid crystal aligning agent>
The liquid crystal aligning agent of this invention is comprised as a solution-like composition formed by melt | dissolving and containing in the organic solvent said specific polymer and the other component arbitrarily used as needed.
Examples of the organic solvent used in the liquid crystal aligning agent of the present invention include N-methyl-2-pyrrolidone, γ-butyrolactone, γ-butyrolactam, N, N-dimethylformamide, N, N-dimethylacetamide, 4-hydroxy- 4-methyl-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol-n-propyl ether , Ethylene glycol-i-propyl ether, ethylene glycol-n-butyl ether (butyl cellosolve), ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl Ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diisobutyl ketone, isoamyl propionate, isoamyl isobutyrate, diisopentyl ether, ethylene carbonate, propylene carbonate, etc. And one or more selected from these can be used.

The solid content concentration in the liquid crystal aligning agent of the present invention (the ratio of the total weight of components other than the solvent in the liquid crystal aligning agent to the total weight of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility, and the like. However, it is preferably in the range of 1 to 10% by weight. By setting the solid content concentration in this range, a liquid crystal alignment film having an appropriate film thickness can be formed with good coating properties, which is preferable.
The particularly preferable solid content concentration range varies depending on the method used when the liquid crystal aligning agent is applied on the substrate. For example, when the spinner method is used, the solid content concentration is particularly preferably in the range of 1.5 to 4.5% by weight. In the case of the printing method, the solid content concentration is particularly preferably in the range of 3 to 9% by weight. In the case of the ink jet method, the solid content concentration is particularly preferably in the range of 1 to 5% by weight.
The temperature at the time of preparing the liquid crystal aligning agent of this invention becomes like this. Preferably it is 10-50 degreeC, More preferably, it is 20-30 degreeC.

<Method for forming liquid crystal alignment film>
A liquid crystal aligning film can be formed by using the liquid crystal aligning agent of this invention, for example through the following processes.
(1) A step of applying the liquid crystal aligning agent of the present invention on the substrate to form a coating film (application step), and (2) a step of irradiating the coating film with light (light irradiation step).

(1) Coating process When applying the liquid crystal aligning agent of this invention to the liquid crystal display element which has a liquid crystal cell of a vertical electric field system, it is each transparent as a pair of 2 board | substrates with which the patterned transparent conductive film is provided. The coating film is formed by applying the liquid crystal aligning agent of the present invention on the conductive conductive film forming surface. On the other hand, when the liquid crystal aligning agent of the present invention is applied to a liquid crystal display element having a transverse electric field type liquid crystal cell, a substrate having a pair of electrodes in which a transparent conductive film or a metal film is patterned in a comb shape on one side And a counter substrate on which no electrode is provided, and a coating film is formed by applying the liquid crystal aligning agent of the present invention to the comb-shaped electrode forming surface and one surface of the counter substrate, respectively.
In any of the above cases, examples of the substrate include glass such as float glass and soda glass;
A transparent substrate made of a plastic such as polyethylene terephthalate, polybutylene terephthalate, polyethersulfone, or polycarbonate can be used. As the transparent conductive film, for example, an ITO film made of In ₂ O ₃ —SnO _{2 or} a NESA (registered trademark) film made of SnO ₂ can be used. As the metal film, for example, a film made of a metal such as chromium can be used. For patterning the transparent conductive film and the metal film, for example, a method of forming a pattern by a photo-etching method or a sputtering method after forming a transparent conductive film without a pattern, or having a desired pattern when forming the transparent conductive film For example, a method using a mask can be used.
After applying a functional silane compound, titanate, etc. on the substrate and the electrode in advance in order to further improve the adhesion between the substrate and the electrode and the coating film when applying the liquid crystal aligning agent on the substrate. A pretreatment for heating may be performed.

  The liquid crystal aligning agent can be applied onto the substrate by an appropriate application method such as an offset printing method, a spin coating method, a roll coater method, or an ink jet printing method. After coating, the coated surface can be preheated (prebaked) and then baked (postbaked) to form a coating film. The prebaking condition is, for example, a heating time of 0.1 to 5 minutes at a heating temperature of 40 to 120 ° C., and the postbaking condition is, for example, a heating temperature of 120 to 300 ° C., preferably 150 to 250 ° C. The heating time is 5 to 200 minutes, preferably 10 to 100 minutes. The film thickness of the coating film after post-baking is preferably 0.001 to 1 μm, and more preferably 0.005 to 0.5 μm.

(2) Light irradiation process By irradiating polarized light with respect to the coating film formed as described above, the liquid crystal alignment ability can be imparted to the coating film to form a liquid crystal alignment film.
As light to be irradiated here, for example, ultraviolet rays or visible rays including light having a wavelength of 150 to 800 nm can be used. Ultraviolet light containing light having a wavelength of 200 to 400 nm is preferable. As a light source to be used, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, a deuterium lamp, a metal halide lamp, an argon resonance lamp, a xenon lamp, an Hg-Xe lamp, an excimer laser, or the like can be used. The ultraviolet rays in the preferable wavelength region can be obtained by means of using the light source in combination with, for example, a filter, a diffraction grating, or the like.
When the radiation used for light irradiation is polarized (linearly polarized or partially polarized), it can be irradiated from a direction perpendicular to the coating surface or from an oblique direction to give a pretilt angle. Good. On the other hand, when irradiating non-polarized radiation, it is necessary to perform irradiation from an oblique direction with respect to the coating surface.
The irradiation dose of light, preferably less than 1 J / ^{m 2} or more 10,000 J / ^{m 2,} more preferably from 10~3,000J / ^{m 2.} In addition, when providing the liquid crystal aligning ability by the photo-alignment method to the coating film formed from the conventionally known liquid crystal aligning agent, the irradiation dose of 10,000 J / m < ² > or more was required. However, when the liquid crystal aligning agent of the present invention is used, the radiation irradiation amount in the photo-alignment method is 5,000 J / m ² or less, further 3,000 J / m ² or less, further 1,000 J / m ² or less. Can provide good liquid crystal alignment ability, which contributes to the reduction of the manufacturing cost of the liquid crystal display element.
Since the liquid crystal alignment film formed as described above can obtain the liquid crystal alignment ability with a light irradiation amount smaller than that in the prior art, it contributes to the reduction of the manufacturing cost of the liquid crystal display element.

<Liquid crystal display element>
Using the substrate having the liquid crystal alignment film formed as described above, a liquid crystal display element can be manufactured as follows.
A pair of substrates on which the liquid crystal alignment film is formed as described above is prepared, and a liquid crystal cell having a configuration in which the liquid crystal is sandwiched between the pair of substrates is manufactured. In order to manufacture a liquid crystal cell, the following two methods can be mentioned, for example.
As a first method, a pair of substrates are arranged to face each other through a gap (cell gap) so that the liquid crystal alignment films face each other, and the peripheral portions of the pair of substrates are bonded together using a sealant, and the substrate surface and A method of manufacturing a liquid crystal cell can be mentioned by injecting and filling liquid crystal into a cell gap partitioned by a sealing agent and then sealing the injection hole.
As a second method, for example, an ultraviolet light curable sealing material is applied to a predetermined location on one of the two substrates on which the liquid crystal alignment film is formed, and further, a predetermined number of locations on the surface of the liquid crystal alignment film. After the liquid crystal is dropped on the liquid crystal, the other substrate is bonded so that the liquid crystal alignment film faces, the liquid crystal is spread on the substrate surface, and then the entire surface of the substrate is irradiated with ultraviolet light to cure the sealing agent, thereby liquid crystal Mention may be made of the method of producing the cell. The second method is a method called an ODF (One Drop Fill) method.
In any of the above methods, it is desirable to remove the flow alignment at the time of filling the liquid crystal by heating the liquid crystal cell to a temperature at which the liquid crystal used takes an isotropic phase and then gradually cooling it to room temperature.

And the liquid crystal display element of this invention can be obtained by bonding a polarizing plate on the outer surface of a liquid crystal cell. Here, a desired liquid crystal display element is obtained by appropriately adjusting the angle formed by the polarization direction of the irradiated linearly polarized light and the angle between each substrate and the polarizing plate in the pair of substrates on which the liquid crystal alignment film is formed. be able to.
As the sealing agent, for example, an aluminum oxide sphere as a spacer and an epoxy resin containing a curing agent can be used.
As the liquid crystal, for example, nematic liquid crystal, smectic liquid crystal, or the like can be used.

When manufacturing a TN type liquid crystal cell or an STN type liquid crystal cell, a nematic type liquid crystal having positive dielectric anisotropy is preferable. For example, biphenyl type liquid crystal, phenyl cyclohexane type liquid crystal, ester type liquid crystal, terphenyl type liquid crystal, biphenyl cyclohexane type A liquid crystal, a pyrimidine liquid crystal, a dioxane liquid crystal, a bicyclooctane liquid crystal, a cubane liquid crystal, or the like is used. In addition, cholesteric liquid crystals such as cholesteryl chloride, cholesteryl nonate, cholesteryl carbonate; chiral agents such as those sold under the trade names “C-15” and “CB-15” (manufactured by Merck); p- A ferroelectric liquid crystal such as decyloxybenzylidene-p-amino-2-methylbutylcinnamate may be further added and used.
On the other hand, when manufacturing a vertical alignment type liquid crystal cell, a nematic liquid crystal having negative dielectric anisotropy is preferable, for example, dicyanobenzene liquid crystal, pyridazine liquid crystal, Schiff base liquid crystal, azoxy liquid crystal, biphenyl liquid crystal, For example, phenylcyclohexane-based liquid crystal can be used.

The polarizing plate used outside the liquid crystal cell is composed of a polarizing film called “H film” in which polyvinyl alcohol is stretched and oriented while absorbing iodine and sandwiched between cellulose acetate protective films, or the H film itself. A polarizing plate etc. can be mentioned. The liquid crystal display element of the present invention thus produced is excellent in various performances such as display characteristics and electrical characteristics.
The liquid crystal display device manufactured by applying the liquid crystal aligning agent of the present invention has an advantage that the discriminating is very rare even when a bead spacer of a type in which beads are dispersed in the display area is used as a spacer. Have
The liquid crystal aligning agent of the present invention is preferably applied to a liquid crystal display element having a transverse electric field type liquid crystal cell in that the effect of improving the discrimination is particularly excellent.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.
The following synthesis examples ensured the required amount of products in the following synthesis examples and examples by repeating the operation at the following synthesis scale as necessary.
<Synthesis of Compound Represented by Formula (A-1)>
Synthesis Example A1-1
Compound (a-1) was synthesized according to the following scheme.

In a 500 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, 24.9 g of 4-bromodiphenyl ether, 0.22 g of palladium acetate, 1.22 g of tri (o-tolyl) phosphine, 56 mL of triethylamine, and acrylic acid 8. 2 mL and 200 mL of N, N-dimethylacetamide were charged, and the reaction was performed by heating and stirring at 120 ° C. for 3 hours. After completion of the reaction, the filtrate obtained by filtering the reaction mixture was mixed with 500 mL of ethyl acetate, washed successively with dilute hydrochloric acid twice and water three times, and the solvent was removed under reduced pressure. The obtained solid was recrystallized from ethanol to obtain 19.2 g of compound (a-1-1).
In a 100 mL one-necked flask equipped with a reflux tube and a nitrogen introduction tube, 12.0 g of the compound (a-1-1) obtained above, 20 mL of thionyl chloride and 0.1 mL of dimethylformamide were mixed and mixed at 80 ° C. The reaction was carried out with heating and stirring for a period of time. After completion of the reaction, unreacted thionyl chloride was removed from the reaction mixture under reduced pressure, and then mixed with 50 mL of tetrahydrofuran to obtain a solution (1).

In a separate container, 11.1 g of 2- (2,4-dinitrophenyl) ethanol, 100 mL of tetrahydrofuran, and 10.4 ml of triethylamine were mixed and stirred at 0 ° C. The solution (1) obtained above was added dropwise thereto over 1 hour, and the reaction was carried out by stirring at 20 ° C. for 6 hours. After completion of the reaction, the reaction mixture was mixed with 300 mL of ethyl acetate and washed successively with dilute hydrochloric acid twice and water three times. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol to obtain 19.3 g of Compound (a-1-2).
In a 1,000 mL three-necked flask equipped with a reflux tube, a thermometer and a nitrogen introduction tube, 18.4 g of the compound (a-4-2) obtained above, 55.5 g of zinc powder, 9.1 g of ammonium chloride, ethanol 170 mL and 170 mL of tetrahydrofuran were mixed and stirred at 0 ° C. Distilled water 25mL was dripped here over 1 hour, Then, it stirred at 20 degreeC for 12 hours, and reacted. After completion of the reaction, the filtrate obtained by filtering the reaction mixture was mixed with 600 mL of ethyl acetate and washed with water four times. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol to obtain 10.5 g of a diamine compound (a-1).

Synthesis Example A1-2
Compound (a-2) was synthesized according to the following scheme.

In a 500 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, 24.9 g of 4-bromodiphenyl ether, 0.22 g of palladium acetate, 1.22 g of tri (o-tolyl) phosphine, 56 mL of triethylamine, and acrylic acid 8. 2 mL and 200 mL of N, N-dimethylacetamide were charged, and the reaction was performed by heating and stirring at 120 ° C. for 3 hours. After completion of the reaction, the filtrate obtained by filtering the reaction mixture was mixed with 500 mL of ethyl acetate, washed successively with dilute hydrochloric acid twice and water three times, and the solvent was removed under reduced pressure. The obtained solid was recrystallized from ethanol to obtain 19.2 g of compound (a-2-1).
In a 100 mL one-necked flask equipped with a reflux tube and a nitrogen introducing tube, 12.0 g of the compound (a-2-1) obtained above, 20 mL of thionyl chloride and 0.1 mL of dimethylformamide were mixed, and the mixture was stirred at 80 ° C. for 1 hour. The reaction was carried out with heating and stirring. After completion of the reaction, the reaction mixture was freed from unreacted thionyl chloride under reduced pressure, and then mixed with 50 mL of tetrahydrofuran to obtain a solution (2).
In a separate container, 36 mL of 1,3-propanediol, 50 mL of tetrahydrofuran and 10.4 mL of triethylamine were mixed and stirred at 0 ° C. The solution (2) obtained above was added dropwise thereto over 1 hour, and the reaction was carried out by stirring at 20 ° C. for 3 hours. After completion of the reaction, the reaction mixture was mixed with 300 mL of ethyl acetate, and washed successively with dilute hydrochloric acid twice and water three times. By removing the solvent under reduced pressure, 13.5 g of compound (a-2-2) was obtained.

In a 200 mL three-necked flask equipped with a reflux tube, a thermometer and a nitrogen introduction tube, 11.9 g of the compound (a-2-2) obtained above, 7.8 g of 2,4-dinitrofluorobenzene, 12 mL of triethylamine and tetrahydrofuran 60 mL was mixed and reacted by heating and stirring at 40 ° C. for 8 hours. After completion of the reaction, the reaction mixture was mixed with 300 mL of ethyl acetate and washed 4 times with water. By removing the solvent under reduced pressure, 16.6 g of compound (a-2-3) was obtained.
In a 1,000 mL three-necked flask equipped with a reflux tube, a thermometer and a nitrogen introduction tube, 16.6 g of the compound (a-2-3) obtained above, 46.7 g of zinc powder, 7.7 g of ammonium chloride, ethanol 140 mL and 140 mL of tetrahydrofuran were mixed and stirred at 0 ° C. Distilled water (21 mL) was added dropwise over 1 hour, and the reaction was carried out by stirring at 20 ° C. for 12 hours. After completion of the reaction, the filtrate obtained by filtering the reaction mixture was mixed with 400 mL of ethyl acetate and washed four times with water. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol to obtain 5.8 g of a diamine compound (a-2).

Synthesis Example A1-3
Compound (a-3) was synthesized according to the following scheme.

In a 500 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen inlet tube, 26.3 g of 1-bromo-4- (4-methylphenoxy) benzene, 0.22 g of palladium acetate, tri (o-tolyl) phosphine 22 g, 56 mL of triethylamine, 8.2 mL of acrylic acid and 200 mL of N, N-dimethylacetamide were charged, and the reaction was performed by heating and stirring at 120 ° C. for 3 hours. After completion of the reaction, the filtrate obtained by filtering the reaction mixture was mixed with 500 mL of ethyl acetate, washed successively with dilute hydrochloric acid twice and water three times, and the solvent was removed under reduced pressure. The obtained solid was recrystallized from ethanol to obtain 19.9 g of compound (a-3-1).
In a 100 mL one-necked flask equipped with a reflux tube and a nitrogen introduction tube, 12.7 g of the compound (a-3-1) obtained above, 20 mL of thionyl chloride and 0.1 mL of dimethylformamide were mixed, and 1 hour at 80 ° C. The reaction was carried out with heating and stirring. After completion of the reaction, unreacted thionyl chloride was removed from the reaction mixture under reduced pressure, and then mixed with 50 mL of tetrahydrofuran to obtain a solution (3-1).
In a separate container, 36 mL of 1,3-propanediol, 50 mL of tetrahydrofuran and 10.4 mL of triethylamine were mixed and stirred at 0 ° C. The solution (3-1) obtained above was added dropwise thereto over 1 hour, and the reaction was carried out by stirring at 20 ° C. for 3 hours. After completion of the reaction, the reaction mixture was mixed with 300 mL of ethyl acetate and washed successively with dilute hydrochloric acid twice and water three times. By removing the solvent under reduced pressure, 13.7 g of compound (a-3-2) was obtained.

In a 100 mL one-necked flask equipped with a reflux tube and a nitrogen introduction tube, 11.5 g of 3,5-dinitrobenzoyl chloride and 50 mL of tetrahydrofuran were mixed to obtain a solution (3-1).
In a separate container, 16.3 g of the compound (a-3-2) obtained above, 100 mL of tetrahydrofuran and 10.4 mL of triethylamine were mixed and stirred at 0 ° C. The solution (3-2) obtained above was added dropwise thereto over 1 hour, and the reaction was carried out by stirring at 20 ° C. for 6 hours. After completion of the reaction, the reaction mixture was mixed with 300 mL of ethyl acetate and washed successively with dilute hydrochloric acid twice and water three times. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol to obtain 20.3 g of compound (a-3-3).
In a 1,000 mL three-necked flask equipped with a reflux tube, a thermometer and a nitrogen introduction tube, 21.5 g of the compound (a-3-3) obtained above, 55.5 g of zinc powder, 9.1 g of ammonium chloride, ethanol 170 mL and 170 mL of tetrahydrofuran were mixed and stirred at 0 ° C. Distilled water 25mL was dripped here over 1 hour, Then, it stirred at 20 degreeC for 12 hours, and reacted. After completion of the reaction, the filtrate obtained by filtering the reaction mixture was mixed with 600 mL of ethyl acetate and washed with water four times. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol to obtain 12.9 g of a diamine compound (a-3).

Comparative Synthesis Example A1-4
Compound (a-4) was synthesized according to the following scheme.

In a 100 mL one-necked flask equipped with a reflux tube and a nitrogen introduction tube, 7.4 g of trans-cinnamic acid, 20 mL of thionyl chloride and 0.1 mL of dimethylformamide were mixed and heated at 80 ° C. for 1 hour with stirring. It was. After completion of the reaction, unreacted thionyl chloride was removed from the reaction mixture under reduced pressure, and then mixed with 50 mL of tetrahydrofuran to obtain a solution (4).
In a separate container, 11.1 g of 2- (2,4-dinitrophenyl) ethanol, 100 mL of tetrahydrofuran and 10.4 mL of triethylamine were mixed and stirred at 0 ° C. The solution (4) obtained above was added dropwise thereto over 1 hour, and the reaction was carried out by stirring at 20 ° C. for 6 hours. After completion of the reaction, the reaction mixture was mixed with 300 mL of ethyl acetate and washed successively with dilute hydrochloric acid twice and water three times. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol to obtain 14.5 g of Compound (a-4-1).
In a 1,000 mL three-necked flask equipped with a reflux tube, a thermometer and a nitrogen inlet tube, 14.5 g of the compound (a-4-1) obtained above, 55.5 g of zinc powder, 9.1 g of ammonium chloride, ethanol 170 mL and 170 mL of tetrahydrofuran were mixed and stirred at 0 ° C. Distilled water 25mL was dripped here over 1 hour, Then, it stirred at 20 degreeC for 12 hours, and reacted. After completion of the reaction, the filtrate obtained by filtering the reaction mixture was mixed with 600 mL of ethyl acetate and washed with water four times. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol to obtain 8.5 g of a diamine compound (a-4).

Comparative Synthesis Example A1-5
Compound (a-5) was synthesized according to the following scheme.

In a 100 mL one-necked flask equipped with a reflux tube and a nitrogen introduction tube, 11.2 g of 4-phenylcinnamic acid, 20 mL of thionyl chloride and 0.1 mL of dimethylformamide were mixed, and the reaction was performed by heating and stirring at 80 ° C. for 1 hour. It was. After completion of the reaction, unreacted thionyl chloride was removed from the reaction mixture under reduced pressure, and then mixed with 50 mL of tetrahydrofuran to obtain a solution (5).
In a separate container, 11.1 g of 2- (2,4-dinitrophenyl) ethanol, 100 mL of tetrahydrofuran and 10.4 mL of triethylamine were mixed and stirred at 0 ° C. The solution (5) obtained above was added dropwise thereto over 1 hour, and the reaction was carried out by stirring at 20 ° C. for 6 hours. After completion of the reaction, the reaction mixture was mixed with 300 mL of ethyl acetate and washed successively with dilute hydrochloric acid twice and water three times. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol to obtain 18.1 g of compound (a-5-1).
In a 1,000 mL three-necked flask equipped with a reflux tube, a thermometer and a nitrogen introduction tube, 17.7 g of the compound (a-5-1) obtained above, 55.5 g of zinc powder, 9.1 g of ammonium chloride, 170 mL of ethanol And 170 mL of tetrahydrofuran were mixed and stirred at 0 ° C. Distilled water 25mL was dripped here over 1 hour, Then, it stirred at 20 degreeC for 12 hours, and reacted. After completion of the reaction, the filtrate obtained by filtering the reaction mixture was mixed with 600 mL of ethyl acetate and washed with water four times. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol to obtain 10.2 g of a diamine compound (a-5).

Synthesis Example A1-6
Compound (a-6) was synthesized according to the following scheme.

A well-dried 500 mL four-necked flask is quickly equipped with a stir bar, condenser, three-way cock and thermometer, where 51.8 g of 4-bromobutyronitrile, 4- (4-bromophenoxy) phenol 92. 8 g, potassium carbonate 96.7 g and 200 mL of dehydrated dimethylacetamide as a solvent were charged. This was heated to 120 ° C. with stirring, and the reaction was carried out for 6 hours while maintaining this temperature. After completion of the reaction, the reaction mixture was filtered and washed twice with water using a 1 L separatory funnel. The organic phase was then dried over magnesium sulfate overnight and the solvent was removed under reduced pressure. The obtained solid was recrystallized from methanol to obtain 81.4 g of compound (a-6-1).
Next, in a 500 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, 33.2 g of the compound (a-6-1) obtained above, 0.22 g of palladium acetate, and tri (o-tolyl) phosphine 1.22 g, triethylamine 56 mL, acrylic acid 8.2 mL and N, N-dimethylacetamide 200 mL were charged. The reaction was carried out at 120 ° C. with heating and stirring for 3 hours. After completion of the reaction, the reaction mixture was filtered, and the obtained filtrate was mixed with 500 mL of ethyl acetate, washed successively with dilute hydrochloric acid twice and water three times, and the solvent was removed under reduced pressure. The obtained solid was recrystallized from ethanol to obtain 23.9 g of compound (a-6-2).

In a 100 mL one-necked flask equipped with a reflux tube and a nitrogen introduction tube, 16.2 g of the compound (a-6-2) obtained above, 20 mL of thionyl chloride and 0.1 mL of dimethylformamide were mixed, and 1 The reaction was carried out with heating and stirring for a period of time. After completion of the reaction, unreacted thionyl chloride was removed from the reaction mixture under reduced pressure, and then mixed with 50 mL of tetrahydrofuran to obtain a solution (6).
In a separate container, 11.1 g of 2- (2,4-dinitrophenyl) ethanol, 100 mL of tetrahydrofuran, and 10.4 ml of triethylamine were mixed and stirred at 0 ° C. The solution (6) obtained above was added dropwise over 1 hour, and the reaction was carried out by stirring at 20 ° C. for 6 hours. After completion of the reaction, the reaction mixture was mixed with 300 mL of ethyl acetate and washed successively with dilute hydrochloric acid twice and water three times. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol to obtain 22.3 g of Compound (a-6-3).
In a 1,000 mL three-necked flask equipped with a reflux tube, a thermometer, and a nitrogen introduction tube, 21.9 g of the compound (a-6-3) obtained above, 55.5 g of zinc powder, 9.1 g of ammonium chloride, ethanol 170 mL and 170 mL of tetrahydrofuran were mixed and stirred at 0 ° C. Distilled water 25mL was dripped here over 1 hour, Then, it stirred at 20 degreeC for 12 hours, and reacted. After completion of the reaction, the filtrate obtained by filtering the reaction mixture was mixed with 600 mL of ethyl acetate and washed with water four times. The solvent was removed under reduced pressure, and the obtained solid was recrystallized from ethanol to obtain 12.4 g of a diamine compound (a-6).

<Synthesis of specific polymer (polyamic acid)>
Synthesis example PA-1
2,3,5-tricarboxycyclopentylacetic acid dianhydride 2.24 g (0.01 mol) as tetracarboxylic dianhydride and compound (a-1) obtained in Synthesis Example A1-1 as diamine 3. 74 g (0.01 mol) was dissolved in 11.1 g of N-methyl-2-pyrrolidone (NMP) and reacted at 40 ° C. for 3 hours to obtain a solution 17 containing 35% by weight of polyamic acid (PA-1). 0.1 g was obtained.
A small amount of this polyamic acid solution was taken and diluted with NMP to obtain a polymer concentration of 10% by weight. The solution viscosity was 33 mPa · s.

Synthesis example PA-2
2.2,4,5 (0.01 mol) of 2,3,5-tricarboxycyclopentylacetic acid dianhydride as tetracarboxylic dianhydride and compound (a-2) obtained in Synthesis Example A1-2 above as diamine. 04 g (0.01 mol) was dissolved in 11.7 g of NMP and reacted at 40 ° C. for 3 hours to obtain 18.0 g of a solution containing 35% by weight of polyamic acid (PA-2).
A small amount of this polyamic acid solution was taken and diluted with NMP to give a polymer concentration of 10% by weight. The solution viscosity was 27 mPa · s.

Synthesis example PA-3
1.96 g (0.01 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride and compound (a-3) obtained in Synthesis Example A1-3 above as diamine 4.46 g (0.01 mol) was dissolved in 11.9 g of NMP and reacted at 40 ° C. for 3 hours to obtain 18.3 g of a solution containing 35% by weight of polyamic acid (PA-3).
A small amount of this polyamic acid solution was taken and diluted with NMP to obtain a polymer concentration of 10% by weight. The solution viscosity was 40 mPa · s.

<Synthesis of other polymers (polyamic acid)>
Synthesis example PA-4
2,3,5-tricarboxycyclopentylacetic acid dianhydride 2.24 g (0.01 mol) as tetracarboxylic dianhydride and compound (a-4) obtained in Synthesis Example A1-4 above as diamine 82 g (0.01 mol) was dissolved in 9.4 g of NMP and reacted at 40 ° C. for 3 hours to obtain 14.4 g of a solution containing 35% by weight of polyamic acid (PA-4).
A small amount of this polyamic acid solution was taken and diluted with NMP to give a polymer concentration of 10% by weight. The solution viscosity was 35 mPa · s.

Synthesis example PA-5
1.96 g (0.01 mol) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride and compound (a-5) obtained in Synthesis Example A1-5 as diamine 3.58 g (0.01 mol) was dissolved in 103 g of NMP and reacted at 40 ° C. for 3 hours to obtain 15.8 g of a solution containing 35% by weight of polyamic acid (PA-5).
A small amount of this polyamic acid solution was taken and diluted with NMP to obtain a polymer concentration of 10% by weight. The solution viscosity was 50 mPa · s.

Synthesis example PA-6
1.96 g (0.01 g) of 1,2,3,4-cyclobutanetetracarboxylic dianhydride as tetracarboxylic dianhydride and 2.12 g of 2,2′-dimethyl-4,4′-diaminobiphenyl as diamine (0.01 mol) was dissolved in 23.1 g of NMP and reacted at 40 ° C. for 4 hours to obtain 26.0 g of a solution containing 15% by weight of polyamic acid (PA-6). The solution viscosity of this polyamic acid solution was 400 mPa · s.

Synthesis example PA-7
2. 2,4,5-tricarboxycyclopentylacetic acid dianhydride 2.24 g (0.01 mol) as tetracarboxylic dianhydride and compound (a-6) obtained in Synthesis Example A1-6 as diamine 58 g (0.01 mol) was dissolved in 12.6 g of N-methyl-2-pyrrolidone (NMP) and reacted at 40 ° C. for 3 hours, whereby a solution 19 containing 35% by weight of polyamic acid (PA-7) .4 g was obtained.
A small amount of this polyamic acid solution was taken and diluted with NMP to obtain a polymer concentration of 10% by weight. The solution viscosity was 50 mPa · s.

Example 1
<Preparation of liquid crystal aligning agent>
N-methylpyrrolidone (NMP) and butyl cellosolve (BC) are added to a solution containing the polyamic acid PA-1 synthesized in Synthesis Example PA-1 as a polyamic acid, and the solid content concentration is 6.5% by weight. Was made into a solution of NMP / BC = 50/50 (weight ratio) and filtered through a filter having a pore diameter of 0.2 μm to prepare a liquid crystal aligning agent for printability evaluation.
A liquid crystal aligning agent for producing a liquid crystal display element was prepared in the same manner as described above except that the solid content concentration was 3.5% by weight.
<Printability evaluation>
Resin spacers (Sekisui Chemical Co., Ltd., “Micropearl EX-0041-AC4”) having a diameter of about 4.1 μm on a 6-inch silicon wafer so that the number is about 20 to 30 per 10 cm ^2. The silicon wafer was sprayed and heat-treated for 10 minutes on a hot plate set at 120 ° C. to prepare a silicon wafer having a fixing spacer.
The liquid crystal aligning agent for printability evaluation prepared above is applied onto the silicon wafer with the fixed spacer by a liquid crystal alignment film printer (manufactured by Nissha Printing Co., Ltd.) and heated on a hot plate at 80 ° C. for 1 minute ( After removing the solvent by pre-baking, it was heated (post-baked) on a hot plate at 200 ° C. for 10 minutes to form a coating film having an average film thickness of 800 mm. This coating film was observed with a microscope having a magnification of 20 times, and evaluation was performed by paying attention to printing unevenness and the presence or absence of repelling in the vicinity of the fixed spacer. Here, when printing unevenness and repellency were not observed at all, the printability was “very good”, and when printing unevenness or repellency was observed only very slightly, The case where a large number of at least one was observed was evaluated as “printability”.
The evaluation results are shown in Table 1.

<Evaluation of liquid crystal orientation and voltage holding ratio>
(1) Manufacture of a liquid crystal display element for evaluating liquid crystal orientation and voltage holding ratio A pair of a glass substrate having a metal electrode made of chromium patterned in a comb shape on one side and a counter glass substrate on which no electrode is provided, After applying the liquid crystal aligning agent for manufacturing a liquid crystal display element prepared above to the surface having the electrode of the glass substrate and one surface of the counter glass substrate with a spinner, and prebaking for 1 minute on an 80 ° C. hot plate, The inside was heated (post-baked) at 200 ° C. for 1 hour in an oven purged with nitrogen to form a coating film having a thickness of 0.1 μm. Next, the surface of the coating film was irradiated with polarized ultraviolet rays 400 J / m ² containing a 313 nm emission line from the substrate normal direction using a Hg-Xe lamp and a Grand Taylor prism, respectively, to form a liquid crystal alignment film. A pair of substrates was obtained.
After applying an epoxy resin adhesive containing aluminum oxide spheres having a diameter of 3.5 μm to the outer periphery of the surface having one liquid crystal alignment film of the above substrates by screen printing, the liquid crystal alignment film surfaces of the pair of substrates are opposed to each other, The adhesive was heat-cured at 150 ° C. for 1 hour, with the optical axes of polarized ultraviolet rays being superimposed and pressure-bonded so that the directions projected onto the substrate surface were parallel. Next, a liquid crystal injection, MLC-7028, was filled into the gap between the substrates from the liquid crystal injection port, and then the liquid crystal injection port was sealed with an epoxy adhesive. Furthermore, in order to remove the flow alignment at the time of liquid crystal injection, this was heated at 120 ° C. for 10 minutes and then gradually cooled to room temperature. Next, a polarizing plate is bonded to both outer sides of the substrate by bonding the polarizing plates so that their polarization directions are orthogonal to each other and 45 ° with the direction of the optical axis of the polarized ultraviolet light of the liquid crystal alignment film projected onto the substrate surface. A liquid crystal display element for evaluation of orientation and voltage holding ratio was produced.

(2) Evaluation of liquid crystal orientation With respect to the liquid crystal display element manufactured above, the presence or absence of an abnormal domain in the change in brightness when a voltage of 5 V is turned ON / OFF (applied / released) is observed with an optical microscope. The case where it was not observed was evaluated as “good” liquid crystal alignment, and the case where an abnormal domain was observed was evaluated as “bad” liquid crystal alignment.
The evaluation results are shown in Table 1.
(3) Evaluation of voltage holding ratio A voltage of 5 V was applied to the liquid crystal display element produced above at 60 ° C. with an application time of 60 microseconds and a span of 167 milliseconds, and then 167 milliseconds after release of application. The voltage holding ratio was measured with “VHR-1” manufactured by Toyo Corporation. When this value was 99% or more, the voltage holding ratio was evaluated as “very good”, when 95% or more and less than 99%, “good”, and when it was less than 95%, “bad” was evaluated.

<Evaluation of disclination>
(1) Manufacture of liquid crystal display element for evaluation of disclination In the above-mentioned “Manufacture of liquid crystal display element for evaluation of liquid crystal alignment / voltage holding ratio”, epoxy applied to one of the substrates on which the liquid crystal alignment film is formed The diameter of the aluminum oxide spheres contained in the resin adhesive is set to 5.5 μm, and a bead spacer (Hayakawa Rubber Co., Ltd., Haya beads) having an average particle size of about 5.5 μm is further formed on the substrate at a rate of 20 per 10 cm ^2. A liquid crystal display element for evaluation of disclination was manufactured in the same manner except that a pair of substrates were made to face each other after being dispersed so that the number was about 30.
(2) Evaluation of disclination The liquid crystal display element obtained above was placed on a backlight in a state where no voltage was applied, and a 3 cm square area near the center of the display area was observed with a microscope with a magnification of 20 times. When the number of disclinations (linear white defects) generated between the spacers is 0, the disclination characteristic is “very good”, when 1 to 4 is “good”, 5 or more Was evaluated as “bad”.
The evaluation results are shown in Table 1.

Examples 2-7 and Comparative Examples 1 and 2
Two types of liquid crystal aligning agents were prepared and evaluated in the same manner as in Example 1 except that the types and amounts of the polyamic acids used were as shown in Table 1. The evaluation results are shown in Table 1, respectively.
In Examples 4, 5 and 7, two types of polymers were used in combination when preparing the liquid crystal aligning agent.

Claims (5)

At least one polymer selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic dianhydride and a diamine containing a compound represented by the following formula (A-1) and an imidized polymer thereof ; Liquid crystal aligning agent characterized by containing.

(In formula (A-1) , X ¹ represents an oxygen atom, a sulfur atom, —SO ₂ —, —NH— or a methylene group;
R ¹ and R ² are each independently a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a halogenated alkyl group having 1 to 10 carbon atoms, carbon A halogenated alkoxy group of formula 1 to 10 or the following formula (R ¹² )
^{X-R-Z- + (R} 12)
(Wherein ^{(R 12),} X is a cyano group or a nitro group, R is a methylene group or an alkoxy group having 2 to 6 carbon atoms, Z is a single bond, an oxygen atom, a sulfur atom, _-SO 2 -, -NH-, -COO- or -OCO-, and "+" represents a bond.)
A group represented by
i is an integer from 0 to 5;
j is an integer from 0 to 4, and
Z ¹ is a methylene group, an alkylene group having 2 to 10 carbon atoms, an alkenylene group having 2 to 10 carbon atoms, a cyclohexylene group or a phenylene group,
X ² is a single bond, oxygen atom, sulfur atom, —COO—, —OCO—, —CO—, —SO ₂ — or an amide bond, and
k is an integer of 0-5. ) The liquid crystal aligning agent of Claim ¹ whose group X1 in the said Formula (A-1) is an oxygen atom. Tetracarboxylic dianhydride is 2,3,5-tricarboxycyclopentylacetic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic acid Dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo -3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro-2,5-dioxo -3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 3,5,6-tricarboxy-2-carboxymethylnorbornane-2; 3,5; 6-dianhydride, 2 , 4,6,8-tetra Ruxoxybicyclo [3.3.0] octane-2; 4,6; 8-dianhydride, 3,3 ′, 4,4′-benzophenone tetracarboxylic dianhydride and pyromellitic dianhydride it is intended to include at least one selected, the liquid crystal aligning agent of claim 1. And wherein the formed liquid crystal alignment agent according to any one of claims 1 to 3 liquid crystal alignment film. A liquid crystal display element comprising the liquid crystal alignment film according to claim 4 .