KR101898435B1 - Liquid crystal aligning agent, liquid crystal alignment film, liquid crystal display device and polymer - Google Patents

Abstract

[PROBLEMS] To improve the weather resistance of a liquid crystal alignment film.
(Solution to Problem) At least a compound selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic acid dianhydride with a diamine containing a compound (a) represented by the following formula (A) and a polyimide obtained by dehydrating and ring- One kind of polymer is contained in the liquid crystal aligning agent.

Description

TECHNICAL FIELD [0001] The present invention relates to a liquid crystal alignment film, a liquid crystal alignment film, a liquid crystal alignment film, a liquid crystal alignment film, a liquid crystal alignment film,

The present invention relates to a liquid crystal aligning agent, a liquid crystal alignment film, a liquid crystal display element, a polymer and a compound. Specifically, the present invention relates to a liquid crystal aligning agent capable of improving weather resistance of a liquid crystal alignment film, and a liquid crystal alignment film and a liquid crystal display device manufactured using the liquid crystal aligning agent.

Conventionally, various types of liquid crystal display devices have been developed which have different electrode structures and physical properties of liquid crystal molecules to be used. For example, TN type, STN type, VA type, in-plane switching type (IPS type) Liquid crystal display devices such as FFS type and optical compensation band type (OCB type) are known. These liquid crystal display devices have a liquid crystal alignment film for aligning liquid crystal molecules. As a material of the liquid crystal alignment film, polyamic acid and polyimide are generally used in view of good heat resistance, mechanical strength, and various properties such as affinity with liquid crystal.

Recently, liquid crystal display devices are used not only for display terminals such as personal computers, but also for various purposes such as liquid crystal televisions, car navigation systems, mobile phones, smart phones, and information displays. With this versatility, the liquid crystal display device is required to have higher quality of display quality, and the liquid crystal alignment film, which is one of the constituent members of the liquid crystal display element, is being improved as well as the driving method and the device structure are being improved . For example, an important characteristic of a liquid crystal display element is that the weather resistance is good. More specifically, it is possible to maintain good electrical characteristics (good light resistance) even when exposed to a long driving time or optical stress, It is required to maintain good electrical characteristics (high temperature and high humidity resistance) even under high temperature and high humidity.

Therefore, conventionally, it has been proposed to improve the weatherability of a liquid crystal display element by increasing the imidization rate in a polyimide-based liquid crystal alignment film. On the other hand, when the imidization ratio of the liquid crystal alignment layer is increased, the printability of the liquid crystal aligning agent to the substrate may be deteriorated. Considering various components of the liquid crystal alignment layer material, , And various liquid crystal alignment film materials have been proposed (for example, see Patent Document 1 and Patent Document 2).

Japanese Laid-Open Patent Publication No. 2010-2501 Japanese Laid-Open Patent Publication No. 2011-28223

The demand for higher performance of the liquid crystal display element is further increased. Particularly, in view of the fact that the liquid crystal display element is used in a harsher environment than the conventional one due to its versatility, the display quality is satisfactory even when exposed to stress such as heat or light Is required.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its main object to provide a liquid crystal aligning agent capable of improving the weather resistance of the liquid crystal alignment film, and a liquid crystal alignment film and a liquid crystal display element manufactured using the liquid crystal aligning agent. It is another object of the present invention to provide a novel polymer which can be suitably used for the preparation of a liquid crystal aligning agent and a novel compound used for synthesizing the polymer.

DISCLOSURE OF THE INVENTION The present inventors have intensively studied in order to achieve the above-described problems of the prior art. As a result, they have found that a polymer obtained by a reaction of a tetracarboxylic acid dianhydride and a diamine having a specific structure as a polymer component contained in a liquid crystal aligning agent The above problems can be solved, and the present invention has been solved. Specifically, the present invention provides not only the following liquid crystal aligning agent, liquid crystal alignment film and liquid crystal display device, but also novel polymers and compounds suitable for use in the production of liquid crystal aligning agents.

In one aspect, the present invention relates to a liquid crystal aligning agent containing at least one polymer selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic acid dianhydride with a diamine and a polyimide obtained by dehydrating and ring- , Wherein the diamine comprises a compound (a) represented by the following formula (A):

Only, Am ^1; (formula (A) of, Am ¹ is, and with pyrrolidine dinhwan, piperidin dinhwan or 2 to form a hexamethylene yiminhwan monovalent group with the nitrogen atom, may optionally have a substituent are bonded to these ring parts in, bonded to the nitrogen atom constituting the ring, and X ^2, which may; X ¹ is a single bond, an oxygen atom, a carbonyl group, * -COO-, * -OCO-, -NH- , * -Ar 1 -O-, -O-Ar ¹ -, -COO-Ar ¹ -, or * -R ³ -OCO- (wherein Ar ¹ is a bivalent group having a phenylene group or a phenylene group bonded to a substituent and R ³ is a carbon number 1 or 2 alkanediyl group, and in; "*" indicates the bonding hands of the nitrogen-containing heterocyclic ring) and; X ² is a single bond or carbonyl group; and r ¹ is a monovalent organic group, r is each Independently, an integer of 0 to 4, provided that when the sum of r is 2 or more, plural R ¹ independently have the above definition).

The liquid crystal aligning agent of the present invention comprises, as a polymer component, a structure in which one hydrogen atom is removed from two primary amino groups in the compound represented by the above formula (A) (hereinafter also referred to as "specific structure") to the main chain , And at least one of the imidized polymers. With such a liquid crystal aligning agent, a liquid crystal alignment film excellent in light resistance and high temperature and high humidity resistance can be produced.

Further, in a manufacturing process of a liquid crystal alignment film, defects such as pinholes and coating film unevenness may occur in a coating film formed on a substrate using a liquid crystal aligning agent. In this case, there is a case where the coating film is peeled off from the substrate to reuse the substrate. In such a rewiring, it is required that the peeling property of the coating film on the substrate is good. Therefore, according to the liquid crystal aligning agent of the present invention, it is possible to obtain a liquid crystal alignment film having excellent reworkability. The liquid crystal alignment film formed by the liquid crystal aligning agent of the present invention is also excellent in printability.

In the present invention, the compound (a) is preferably represented by the following formula (A-1):

, X ¹ (wherein (A-1) is a single bond, an oxygen atom, a carbonyl group, * -COO-, * -OCO-, -NH- , * -Ar 1 -O-, * -O-Ar 1 -, -COO-Ar ¹ -, or * -R ³ -OCO- (wherein Ar ¹ is a bivalent group having a phenylene group or a phenylene group bonded to a substituent and R ³ is an alkanediyl group having 1 or 2 carbon atoms X ² represents a single bond or a carbonyl group, R ¹ and R ⁴ are each independently a monovalent organic group, and r and s Are independently an integer of 0 to 4, provided that when the sum of r is 2 or more, plural R ¹ independently have the above definition, and when s is 2 or more, plural R ⁴ independently have the above definition ).

In the present invention, X ² is preferably a single bond, wherein X is ^1, * -COO-, * -OCO-, -NH- or * -R ³ -OCO- (single, R ³ is C 1 Or an alkanediyl group of 2). The tetracarboxylic acid dianhydride used in the synthesis of the polymer may be selected from the group consisting of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride and 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride. And at least one kind selected from the group consisting of

In one aspect, the present invention provides a liquid crystal alignment film formed by the liquid crystal aligning agent described above. According to another aspect of the present invention, there is provided a liquid crystal display device including the liquid crystal alignment layer.

In another aspect, the present invention provides a polymer obtained by reacting a diamine containing a compound (a) represented by the formula (A) with a tetracarboxylic acid dianhydride. Also provided is a compound represented by the above formula (A).

(Mode for carrying out the invention)

The liquid crystal aligning agent of the present invention contains at least one polymer selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic acid dianhydride with a diamine and a polyimide obtained by dehydrocondylating the polyamic acid. Hereinafter, the liquid crystal aligning agent of the present invention will be described in detail.

<Polyamic acid>

[Tetracarboxylic acid dianhydride]

Examples of the tetracarboxylic acid dianhydride used for synthesizing the polyamic acid in the present invention include aliphatic tetracarboxylic acid dianhydride, alicyclic tetracarboxylic dianhydride, and aromatic tetracarboxylic dianhydride . As specific examples of these,

As the aliphatic tetracarboxylic acid dianhydride, for example, butanetetracarboxylic dianhydride;

As the alicyclic tetracarboxylic acid dianhydride, for example, 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1,3,3a, 4 , 5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3-furanyl) -naphtho [ (Tetrahydro-2,5-dioxo-3-furanyl) -naphtho [1,2-c] furan-1,3-dione, 3,9- -Tetrahydrofuran-2 &apos;, 5 ' -dione), 5- (2,5-dioxotetrahydro- 3-cyclohexene-1,2-dicarboxylic anhydride, 3,5,6-tricarboxy-2-carboxymethylnorbornane-2: 3,5: 6-2 anhydride , 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4,6,8-2 anhydride, 4,9-dioxatricyclo [5.3.1.0 ^2,6 ] undecane- 3,5,8,10-tetraone, cyclohexanetetracarboxylic acid dianhydride and the like;

As the aromatic tetracarboxylic acid dianhydride, for example, pyromellitic dianhydride and the like; The tetracarboxylic acid dianhydride described in JP-A-2010-97188 can be used.

The tetracarboxylic acid dianhydrides used in the synthesis of the polyamic acid may be used singly or in combination of two or more.

As the tetracarboxylic acid dianhydride used for synthesizing the polyamic acid, it is preferable to include the alicyclic tetracarboxylic dianhydride. More preferably, 2,3,5-tricarboxycyclopentyl acetic acid dianhydride, 1,3,3a, 4,5,9b-hexahydro-5- (tetrahydro-2,5-dioxo-3- 2-c] furan-1,3-dione, 1,3,3a, 4,5,9b-hexahydro-8-methyl-5- (tetrahydro- 3-dione, 2,4,6,8-tetracarboxybicyclo [3.3.0] octane-2: 4,6: 8-2 anhydride and 1,2,3,4-cyclobutane tetracarboxylic acid dianhydride, and particularly preferably 2,3,5-tricarboxycyclopentyl acetic acid (Specific tetracarboxylic acid dianhydride) of a dianhydride and a 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride. The specific tetracarboxylic acid dianhydride is preferably contained in an amount of 10 mol% or more, more preferably 20 to 100 mol%, based on the total amount of the tetracarboxylic acid dianhydride used in the synthesis of the polyamic acid, Particularly preferably 50 to 100 mol%.

The tetracarboxylic acid dianhydride can be obtained by polymerizing with a compound (a) represented by the following formula (A) to obtain a polyamic acid capable of forming a liquid crystal alignment film excellent in light resistance and high temperature and high humidity resistance It has the same function. Therefore, even those not described in the following examples can be used in the present invention.

[Diamine]

The term &quot; compound (a) &quot;

The diamine used for synthesizing the polyamic acid in the present invention includes the compound (a) represented by the following formula (A):

Only, Am ^1; (formula (A) of, Am ¹ is, and with pyrrolidine dinhwan, piperidin dinhwan or 2 to form a hexamethylene yiminhwan monovalent group with the nitrogen atom, may optionally have a substituent are bonded to these ring parts in, bonded to the nitrogen atom constituting the ring, and X ^2, which may; X ¹ is a single bond, an oxygen atom, a carbonyl group, * -COO-, * -OCO-, -NH- , * -Ar 1 -O-, -O-Ar ¹ -, -COO-Ar ¹ -, or * -R ³ -OCO- (wherein Ar ¹ is a bivalent group having a phenylene group or a phenylene group bonded to a substituent and R ³ is a carbon number 1 or 2 alkanediyl group, and in; "*" indicates the bonding hands of the nitrogen-containing heterocyclic ring) and; X ² is a single bond or carbonyl group; and R ¹ is a monovalent organic group, r is each Independently, an integer of 0 to 4, provided that when the sum of r is 2 or more, plural R ¹ independently have the above definition).

In the formula (A), Am ¹ represents a divalent group forming a pyrrolidine ring, a piperidine ring or a hexamethylene imine ring together with a nitrogen atom, and the nitrogen atom constituting these rings (nitrogen-containing heterocycle) Is bonded to one aminophenyl group via "X ² ", and the carbon atom is bonded to the other aminophenyl group via the bivalent group "X ¹ ". The nitrogen-containing heterocycle may have a substituent. Examples of the substituent include an alkyl group having 1 to 10 carbon atoms, an alicyclic hydrocarbon group having 3 to 12 carbon atoms, an aromatic hydrocarbon group having 6 to 12 carbon atoms, a hydroxyl group, a halogen atom An atom, a chlorine atom, a bromine atom and an iodine atom), a nitro group, and a cyano group. The substituent may be a monovalent group having, for example, -O-, -CO-, -COO-, -OCO- or the like between the carbon-carbon bonds of the hydrocarbon group as described above. The hydrogen Or at least a part of the atoms may be substituted with a halogen atom or the like.

Examples of the alkyl group having 1 to 10 carbon atoms include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, a 2-butyl group, Pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group and the like; Examples of the alicyclic hydrocarbon group having 3 to 12 carbon atoms include a cyclopentyl group, a cyclohexyl group and the like; Examples of the aromatic hydrocarbon group having 6 to 12 carbon atoms include a phenyl group, a tolyl group, a benzyl group and the like; Respectively.

The nitrogen-containing heterocycle formed by Am ¹ and the nitrogen atom is particularly preferably a piperidine ring. That is, the compound (a) is preferably a diamine represented by the following formula (A-1):

(Wherein R ⁴ is a monovalent organic group and s is an integer of 0 to 4, provided that when s is 2 or more, plural R ⁴ independently have the above definition; and R ¹ , X ¹ , X ² and r have the same meanings as in the formula (A)).

R ⁴ in the above formula (A-1) is a monovalent organic group, and specific examples thereof include the groups exemplified as substituents which may have a nitrogen-containing heterocyclic ring in the description of Am ¹ . When a plurality of R ⁴ are bonded to the benzene ring, the plural R ^{4 s} may be the same or different.

Formula (A), and so on with respect to X ¹ in (A-1), * -Ar 1 -O-, * -O-Ar 1 - , ^{and, * -COO-Ar 1 - Ar} 1 is in, a phenylene group Or a divalent group in which a substituent is bonded to a phenylene group. As the substituent, for example, a group exemplified as a substituent which may have a nitrogen-containing heterocycle in the description of Am ¹ can be mentioned.

X ¹ is preferably * -COO-, * -OCO-, -NH- or * -R ³ -OCO-, more preferably * -COO-, * -OCO- or -NH-. The bonding position of these X ¹ is not particularly limited, but is preferably 3 or 4 positions relative to the nitrogen atom of the nitrogen-containing heterocyclic ring, and more preferably 4 positions.

X ² is a single bond or a carbonyl group, preferably a single bond.

R ¹ is a monovalent organic group, and specific examples thereof include those exemplified as substituents which may have a nitrogen-containing heterocycle in the description of Am ¹ . When plural R &lt; ¹ &gt; exist in the formula, plural R &lt; ^{1 &gt; s} may be the same or different.

With respect to the formula (A) and formula (A-1) binding site of the primary amino groups on about two amino group in the benzene ring is not particularly limited, and other group (X ¹ or X ^2), 3 position or the 4 Position.

Specific examples of the compound (a) represented by the above formula (A) include those represented by the following formulas (A-1-1) to (A-1-6), respectively. In the synthesis of the polyamic acid, one of the compounds (a) may be used alone or two or more of them may be used in combination.

The compound (a) represented by the formula (A) has all of the same functions in that a polyamic acid having the specific structure described above and excellent in light resistance and high temperature and high humidity resistance can be obtained. Therefore, even those not described in the following examples can be used in the present invention.

"Other diamines"

As the diamine for synthesizing the polyamic acid, only the compound (a) may be used, but other diamines may be used together with the compound (a).

Examples of other diamines usable herein include aliphatic diamines, alicyclic diamines, aromatic diamines, diaminoorganosiloxanes, and the like. Specific examples thereof include aliphatic diamines such as 1,1-meta-xylylenediamine, 1,3-propanediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine and the like;

As the alicyclic diamine, for example, 1,4-diaminocyclohexane, 4,4'-methylenebis (cyclohexylamine), 1,3-bis (aminomethyl) cyclohexane and the like;

Examples of the aromatic diamine include o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'- Diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-bis (trifluoromethyl) -4,4'-diaminobiphenyl, 2,7'- Bis (4-aminophenoxy) phenyl] propane, 9,9-bis (4-aminophenyl) fluorene, 2, 4-diaminodiphenyl ether, (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 4,4 '- (p- phenylenediisopropylidene ) Bisaniline, 4,4'- (m-phenylene diisopropylidene) bisaniline, 1,4-bis (4-aminophenoxy) benzene, 4,4'- , 2,4-diaminopyrimidine, 3,6-diaminoacrylidine, 3,6-diaminocarbazole, N-methyl-3, 6-diaminocarbazole, N- N, N'-bis (4-aminophenyl) benzene, N, N'-bis ) -N, N'-dimethylbenzidine, 1,4-bis- (4-aminophenyl) -piperazine, 3,5-diaminobenzoic acid, dodecaneoxy- 2,4-diaminobenzene, pentadecanoxy-2,4-diaminobenzene, hexadecaneoxy-2,4-diaminobenzene, octadecanoxy-2,4-diaminobenzene, dodecanoxy- 5-diaminobenzene, tetradecanoxy-2,5-diaminobenzene, pentadecanoxy-2,5-diaminobenzene, hexadecanoxy-2,5-diaminobenzene, octadecanoxy- Diaminobenzene, cholestanyloxy-3,5-diaminobenzene, cholestenyloxy-3,5-diaminobenzene, cholestanyloxy-2,4-diaminobenzene, cholestenyloxy- 4-diaminobenzene, 3,5-diaminobenzoic acid cholestanyl, 3,5-diaminobenzoic acid cholestenyl, 3,5-diaminobenzoic acid ranostanyl, 3,6-bis (4 -Aminobenzoyloxy) cholestane, 3,6-bis (4-aminophenoxy) cholestane, 4- (4'-trifluoromethoxybenzoyloxy) cyclohexyl-3,5-diaminobenzoate, 4- (4 '- (trifluoromethylbenzoyloxy) cyclohexyl-3, 5-diaminobenzoate, 1,1-bis 4-heptylcyclohexane, 1,1-bis (4 - ((aminophenoxy) methyl) phenyl) -4-heptylcyclohexane, 1,1- Bis (4 - ((aminophenyl) methyl) phenyl) -4- (4-heptylcyclohexyl) cyclohexane, 2,4- diamino-N, N-diallylaniline, Benzylamine, 1- (2,4-diaminophenyl) piperazine-4-carboxylic acid, 4- (morpholin- (4-aminophenyl) -2,3-dihydro-1,3,3-trimethyl-1H-inden-5-one - amine, 1- (4-aminophenyl) -2 , 3-dihydro-1,3,3-trimethyl-1H-inden-6-amine, 4-aminophenyl-4'- aminobenzoate, 4,4 '- [ Diylbis (piperidine-l, 4-diyl)] dianiline and the following formula (D-1):

(Formula (D-1) of, X and X ^{Ⅰ Ⅱ} is, and respectively a single bond, -O-, -COO- or a -OCO-, R ^Ⅰ is alkanediyl group having a carbon number of 1~3, is a 0 or 1, b is an integer of 0 to 2, c is an integer of 1 to 20, and n is 0 or 1, provided that a and b are not 0 at the same time.

And the like;

As the diaminoorganosiloxane, for example, 1,3-bis (3-aminopropyl) -tetramethyldisiloxane and the like; The diamine described in JP-A-2010-97188 can be used.

Examples of the divalent group represented by "-X ^I - (R ^I -X ^II ) _n -" in the above formula (D-1) include an alkanediyl group having 1 to 3 carbon atoms, * -O-, Or * -OC ₂ H ₄ -O- (provided that a bonding hand having "*" attached thereto is bonded to a diaminophenyl group).

Specific examples of the group "-C _c H _{2c +1} " include a methyl group, an ethyl group, a n-propyl group, an n-butyl group, an n-pentyl group, n-heptadecyl, n-heptadecyl, n-octadecyl, n-hexadecyl, n-hexadecyl, An n-nonadecyl group, and an n-eicosyl group. The two amino groups in the diaminophenyl group are preferably in the 2,4-position or the 3,5-position with respect to the other groups.

Specific examples of the compound represented by the formula (D-1) include compounds represented by the following formulas (D-1-1) to (D-1-3).

As the other diamines used for the synthesis of the polyamic acid, the above-mentioned compounds may be used singly or in combination of two or more.

As the diamine used in the synthesis of the polyamic acid in the present invention, it is preferable that the ratio of the compound (a) is used for the synthesis in view of securing the light resistance, high temperature and high humidity resistance of the liquid crystal display element and the reworkability of the liquid crystal alignment film Based on the total amount of the diamine. The ratio is more preferably 0.1 to 70 mol% in view of making it possible to further improve the initial voltage holding ratio. , More preferably 5 to 50 mol%, and particularly preferably 10 to 50 mol%.

[Molecular Weight Regulator]

In synthesizing the polyamic acid, the endmodified polymer may be synthesized using a suitable molecular weight regulator together with the tetracarboxylic dianhydride and the diamine as described above. By using such a polymer having a terminal modification type, the coating property (printing property) of the liquid crystal aligning agent can be further improved without impairing the effect of the present invention.

Examples of the molecular weight regulator include acid monoanhydrides, monoamine compounds, and monoisocyanate compounds. Specific examples of such acid anhydrides include maleic anhydride, phthalic anhydride, itaconic anhydride, n-decylsuccinic anhydride, n-dodecylsuccinic anhydride, n-tetradecylsuccinic anhydride, n-hexadecylsuccinic anhydride and the like of;

As the monoamine compound, for example, aniline, cyclohexylamine, n-butylamine, n-pentylamine, n-hexylamine, n-heptylamine, n-octylamine and the like;

Examples of the monoisocyanate compound include phenyl isocyanate and naphthyl isocyanate.

The use ratio of the molecular weight regulator is preferably 20 parts by weight or less, more preferably 10 parts by weight or less, based on 100 parts by weight of the total amount of tetracarboxylic acid dianhydride and diamine to be used.

&Lt; Synthesis of Compound (a) &gt;

The compound (a) of the present invention can be synthesized by appropriately combining the methods of organic chemistry. As an example thereof, dinitriles having two nitrophenyl groups in place of two aminophenyl groups in the above formula (A) are synthesized, and then nitro groups of the resulting dinitriles are hydrogenated using a suitable reducing system to form amines And aging.

Herein, when the X ¹ is "* -COO-" or "* -COO-Ar ¹ -", the dinitro group may be substituted with a halide containing a nitrophenyl group such as nitrofluorobenzene, a carboxyl group And then reacting the resultant reaction product with a hydroxyl group derivative having a nitrophenyl group.

In the case where X ¹ is "* -OCO-" or "* -R ³ -OCO-", for example, a halide containing a nitrophenyl group such as nitrofluorobenzene and a secondary cyclic amine compound having a hydroxyl group , And reacting the obtained reaction product with a carbon acid halide containing a nitrophenyl group such as nitrobenzoyl chloride.

When X &^lt; ^{1 &gt;} is &quot; -NH- &quot;, for example, the dinitrile can be obtained by reacting a halopentane containing a nitrophenyl group such as nitrofluorobenzene with a secondary cyclic amine compound having a primary amino group .

When X ¹ is "* -Ar ¹ -O-", for example, by reacting a halide compound containing a nitrophenyl group and a second recurring amine compound having a group "-Ar ¹ -OH" When X ¹ is &quot; * -O-Ar ¹ - &quot;, a hydroxyl group-containing secondary cyclic amine compound such as hydroxypiperidine and a corresponding halophenyl group-containing halide are reacted To obtain the dinitro lozenge.

The reaction for obtaining the dinitro compound as the intermediate is preferably carried out in an organic solvent. The reaction temperature at this time is preferably -20 ° C to 180 ° C, more preferably 0 to 120 ° C. The reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours.

As the organic solvent, a compound usually used in the substitution reaction can be used. Specific examples thereof include alcohols such as methyl alcohol, ethyl alcohol, tetrahydrofuran, toluene, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, 1- Methyl-2-pyrrolidone and the like. In the reaction, if necessary, a base such as sodium hydrogencarbonate, potassium carbonate, lithium carbonate or triethylamine; A nucleophilic agent such as dimethylaminopyridine; And a dehydrating condensation agent such as 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride (EDC).

The reduction reaction of the intermediate may be carried out, for example, using zinc, lithium aluminum hydroxide, a palladium catalyst-hydrogen system, or the like. The reaction temperature at this time is preferably -20 ° C to 180 ° C, more preferably 10 to 120 ° C. The reaction time is preferably 0.1 to 72 hours, more preferably 0.5 to 48 hours. However, the order of synthesizing the compound (a) is not limited to the above method.

<Synthesis of polyamic acid>

The ratio of the tetracarboxylic acid dianhydride and the diamine to be used in the synthesis reaction of the polyamic acid in the present invention is such that the ratio of the acid anhydride group of the tetracarboxylic acid dianhydride to the equivalent of 0.2 to 2 equivalents , More preferably from 0.3 to 1.2 equivalents.

The synthesis reaction of the polyamic acid is preferably carried out in an organic solvent. The reaction temperature is preferably -20 ° C to 150 ° C, more preferably 0 ° C to 100 ° C. The reaction time is preferably 0.1 to 24 hours, more preferably 0.5 to 12 hours.

Examples of the organic solvent include non-protic polar solvents, phenols and their derivatives, alcohols, ketones, esters, ethers, halogenated hydrocarbons, hydrocarbons and the like.

Specific examples of these organic solvents include non-protonic polar solvents such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, Butyrolactone, tetramethylurea, hexamethylphosphotriamide and the like;

As the phenol derivative, for example, m-cresol, xylenol, halogenated phenol and the like;

As the alcohol, for example, methyl alcohol, ethyl alcohol, isopropyl alcohol, cyclohexanol, ethylene glycol, propylene glycol, 1,4-butanediol, triethylene glycol, ethylene glycol monomethyl ether and the like;

Examples of the ketone include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanol and the like;

As the ester, for example, ethyl lactate, butyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, diethyl oxalate, diethyl malonate and the like;

Examples of the ether include diethyl 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, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, Tetrahydrofuran and the like;

As the halogenated hydrocarbon, for example, dichloromethane, 1,2-dichloroethane, 1,4-dichlorobutane, trichloroethane, chlorobenzene, o-dichlorobenzene and the like;

Examples of the hydrocarbon include hexane, heptane, octane, benzene, toluene, xylene, isoamyl propionate, isoamyl isobutyrate, diisopentyl ether and the like; Respectively.

Among these organic solvents, at least one selected from the group consisting of an aprotic polar solvent and a group consisting of phenol and a derivative thereof (first group of organic solvents), or an organic solvent of the first group and at least one alcohol , A ketone, an ester, an ether, a halogenated hydrocarbon, and a hydrocarbon (an organic solvent of the second group). In the latter case, the ratio of the organic solvent of the second group is preferably 50% by weight or less, more preferably 40% by weight or less, based on the total amount of the organic solvent of the first group and the organic solvent of the second group By weight, more preferably not more than 30% by weight.

The amount (a) of the organic solvent used is preferably such that the total amount (b) of the tetracarboxylic acid dianhydride and the diamine is 0.1 to 50 wt% with respect to the total amount (a + b) of the reaction solution.

As described above, a reaction solution obtained by dissolving polyamic acid is obtained. The reaction solution may be directly supplied to the preparation of the liquid crystal aligning agent. Alternatively, the polyamic acid contained in the reaction solution may be isolated and then supplied to the preparation of the liquid crystal aligning agent, or after the isolated polyamic acid is purified, . When the polyamic acid is subjected to dehydration ring closure to form a polyimide, the reaction solution may be directly supplied to the dehydration ring-closing reaction. Alternatively, the polyamic acid contained in the reaction solution may be isolated and then subjected to dehydration ring- May be purified and then subjected to a dehydration ring-closing reaction. The polyamic acid can be isolated and purified by a known method.

<Synthesis of polyimide and polyimide>

The polyimide contained in the liquid crystal aligning agent of the present invention can be obtained by imidizing the polyamic acid synthesized as described above by dehydration ring closure.

The polyimide may be a complete imide cargo which is dehydrated and ring-closed with all of the arboric acid structure possessed by the polyamic acid which is the precursor thereof. The polyimide may be dehydrated and ring-closed only a part of the arboric acid structure to form a partial imide cargo . The imide ratio of the polyimide in the present invention is preferably 30% or more, more preferably 40 to 99%, and still more preferably 50 to 99%. The imidization rate is a percentage of the ratio of the number of imide ring structures to the sum of the number of amide structure and the number of imide ring structure of polyimide. Here, a part of the imide ring may be an isoimide ring.

The dehydration ring-closure of the polyamic acid is preferably carried out by a method of heating the polyamic acid, or a method of dissolving the polyamic acid in an organic solvent, adding a dehydrating agent and a dehydrating ring-closing catalyst to the solution, and optionally heating . Of these, the latter method is preferable.

In the method of adding the dehydrating agent and the dehydrating ring-closing catalyst to the solution of the polyamic acid, an acid anhydride such as acetic anhydride, propionic anhydride, or trifluoroacetic anhydride can be used as the dehydrating agent. The amount of the dehydrating agent to be used is preferably 0.01 to 20 mol based on 1 mol of the acid structure of the polyamic acid. As the dehydration ring-closing catalyst, for example, tertiary amines such as pyridine, collidine, lutidine and triethylamine can be used. The amount of the dehydration ring-closing catalyst to be used is preferably 0.01 to 10 mol based on 1 mol of the dehydrating agent to be used. Examples of the organic solvent used in the dehydration ring-closure reaction include the organic solvents exemplified for use in the synthesis of polyamic acid. The reaction temperature of the dehydration cyclization reaction is preferably 0 to 180 캜, more preferably 10 to 150 캜. The reaction time is preferably 1.0 to 120 hours, more preferably 2.0 to 30 hours.

In this way, a reaction solution containing polyimide is obtained. This reaction solution may be provided as it is in the preparation of a liquid crystal aligning agent, or may be supplied to the preparation of a liquid crystal aligning agent after removing the dehydrating agent and the dehydration ring-closing catalyst from the reaction solution. Alternatively, after the polyimide is isolated, Or may be added to the preparation of a liquid crystal aligning agent after purification of the isolated polyimide. These purification operations can be carried out according to a known method.

&Lt; Solution viscosity and molecular weight of polymer &gt;

The polyamic acid and the polyimide obtained as described above preferably have a solution viscosity of 10 to 800 mPa · s and a solution viscosity of 15 to 500 mPa · s Do. The solution viscosity (mPa 占 퐏) of the polymer is preferably 10 weight% or less by weight, which is prepared by using a good solvent of the polymer (for example,? -Butyrolactone, N-methyl- % Of the polymer solution at 25 占 폚 using an E-type rotational viscometer.

The weight average molecular weight (Mw) of the polyamic acid and polyimide in terms of polystyrene measured by gel permeation chromatography (GPC) is preferably 1,000 to 500,000, and more preferably 2,000 to 300,000. The molecular weight distribution (Mw / Mn) represented by the ratio of Mw to the number average molecular weight (Mn) in terms of polystyrene measured by GPC is preferably 15 or less, and more preferably 10 or less. Within this molecular weight range, good alignment and stability of the liquid crystal display element can be ensured.

<Other components>

The liquid crystal aligning agent of the present invention contains at least any polymer of the above-mentioned polyamic acid and polyimide (hereinafter also referred to as &quot; specific polymer &quot;), but may contain other components as required. Such other components include, for example, other polymers other than the specific polymer, compounds having at least one epoxy group in the molecule (hereinafter referred to as "epoxy group-containing compound"), antioxidant, polyfunctional (meth) , And functional silane compounds.

[Other Polymers]

The other polymer may be used for improving solution characteristics and electrical properties. Examples of such another polymer include polyamic acid (hereinafter referred to as &quot; other polyamic acid &quot;) obtained by reacting the above-exemplified tetracarboxylic acid dianhydride with a diamine compound not containing the compound (a) Polyamide, polysiloxane, cellulose derivative, polyacetal, polystyrene derivative, poly (styrene-phenylmaleimide), polyimide (hereinafter referred to as &quot; other polyimide &quot;), polyamide acid ester, polyester, Derivatives, poly (meth) acrylates, and the like.

When the other polymer is added to the liquid crystal aligning agent, the blending ratio thereof is preferably 50% by weight or less, more preferably 0.1 to 40% by weight, further preferably 0.1 to 30% by weight, based on the total amount of the polymer in the composition desirable.

[Epoxy group-containing compound]

The epoxy group-containing compound can be used for improving adhesion to the substrate surface in the liquid crystal alignment film. Examples of the epoxy group-containing compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether Diallyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, trimethylol propane triglycidyl ether, 2,2-dibromonopentyl glycol di N, N, N ', N'-tetraglycidyl-m-xylylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, N, N'-tetraglycidyl-4,4'-diaminodiphenylmethane, N, N-diglycidyl-benzylamine, N, N-diglycidylaminomethylcyclohexane, N-diglycidyl-cyclohexylamine, the epoxy group-containing polyorganosiloxane described in International Publication No. 2009/096598, and the like As it can be.

When these epoxy group-containing compounds are added to the liquid crystal aligning agent, the blending ratio thereof is preferably 40 parts by weight or less, more preferably 0.1 to 30 parts by weight per 100 parts by weight of the total amount of the polymers contained in the liquid crystal aligning agent.

[Antioxidant]

The antioxidant is used for the purpose of nullifying the peroxy radical or hydroperoxide generated by energy such as ultraviolet rays or heat and suppressing deterioration of the electric characteristics of the liquid crystal display element. Examples of the antioxidant include phenol-based antioxidants, amine-based antioxidants, phosphorus-based antioxidants, sulfur-based antioxidants, and blend compounds of these. Specific examples of such antioxidants include ADEKASTAB AO-20, AO-30, AO-40, AO-40, and AO- IRGAMOX series such as IRGANOX 1050, IRGAOX 1076, IRGAMOD 295 and the like (manufactured by BASF Japan); Examples of amine antioxidants include adekastab LA-52, adekastab LA series such as LA LA-63 (manufactured by ADEKA), CHIMASSORB series such as CHIMASSORB 119, TINUVIN series such as TINUVIN 622 and TINUVIN 123 , Manufactured by BASF Japan);

PEP-8, copper HP-10, copper 2112 (manufactured by ADEKA), GSY-P101 (manufactured by Sakai Kagaku Kogyo Co., Ltd.), IRGAFOS 168, IRGAFOS series such as IRGAFOS P-EPQ (manufactured by BASF Japan); Examples of the sulfur-based antioxidant include adecastab AO-412, AO-503 (manufactured by ADEKA), IRGANOX PS 800, IRGANOX PS 802 (manufactured by BASF Japan); TINUVIN series (manufactured by BASF Japan) such as adecastab A-611, A-612, AO-37, AO-15 (manufactured by ADEKA) and TINUVIN 111 as blend- My back; . The antioxidants may be used alone or in combination of two or more.

As the antioxidant to be used, a phenol-based antioxidant and an amine-based antioxidant are particularly preferable. When these antioxidants are added to the liquid crystal aligning agent, the proportion thereof is preferably 10 parts by weight or less, more preferably 5 parts by weight or less, and more preferably 0.1 to 3 parts by weight, relative to 100 parts by weight of the total amount of the polymer More preferable.

[Multifunctional (meth) acrylate]

The polyfunctional (meth) acrylate can be used for improving the weather resistance of the liquid crystal display element. Examples of the polyfunctional (meth) acrylate include ethylene glycol diacrylate, ethylene glycol dimethacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, 1,9 -Nonanediol diacrylate, 1,9-nonanediol dimethacrylate, tetraethylene glycol diacrylate, tetraethylene glycol dimethacrylate, polypropylene glycol diacrylate, polypropylene glycol dimethacrylate, bis Pentaerythritol triacrylate, pentaerythritol triacrylate, pentaerythritol triacrylate, pentaerythritol triacrylate, pentaerythritol tetramethacrylate, pentaerythritol tetramethacrylate, pentaerythritol tetramethacrylate, , Pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, dipentaerythritol pentaacrylate, dipentaerythritol pentaacrylate, Tri (2-acryloyloxyethyl) phosphate, tri (2-methacryloyloxyethyl) phosphate, and the like can be used in combination with a polyfunctional monomer such as trimethylolpropane trimethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, . As the polyfunctional (meth) acrylate, a commercially available product may be used.

When these polyfunctional (meth) acrylates are added to the liquid crystal aligning agent, the blending ratio thereof is preferably 100 parts by weight or less, more preferably 50 parts by weight or less, more preferably 0.1 to 30 parts by weight based on 100 parts by weight of the total amount of the polymers By weight is more preferable.

[Functional silane compound]

The functional silane compound can be used to improve the printability of the liquid crystal aligning agent. Examples of such a 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-ureidopropyltriethoxy Silane, N-ethoxycarbonyl-3-aminopropyltrimethoxysilane, N-ethoxycarbonyl-3-aminopropyltriethoxysilane, N-triethoxysilylpropyltriethylenetriamine, N- Trimethoxysilyl-1,4,7-triazadecane, 10-triethoxysilyl-1,4,7-triazadecane, 9-trimethoxysilyl-3 , 6-diazanonyl acetate, 9-triethoxysilyl-3,6-diazanonyl acetate, methyl 9-trimethoxysilyl-3,6-diazanonate, Benzyl-3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N- N-phenyl-3-aminopropyltriethoxysilane, glycidoxymethyltrimethoxysilane, glycidoxymethyltriethoxysilane, 2-glycidoxyethyltrimethoxysilane, 2-glycidoxyethyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyltriethoxysilane, and the like.

When these functional silane compounds are added to the liquid crystal aligning agent, the mixing ratio thereof is preferably 2 parts by weight or less, more preferably 0.02 to 0.2 parts by weight based on 100 parts by weight of the total of the polymers.

<Solvent>

The liquid crystal aligning agent of the present invention is constituted by dissolving the polymer component and optionally other additives optionally mixed in an organic solvent.

Examples of the organic solvent to be used include organic solvents such as N-methyl-2-pyrrolidone,? -Butyrolactone,? -Butyrolactam, N, N-dimethylformamide, N, N-dimethylacetamide, Methylene-2-pentanone, ethylene glycol monomethyl ether, butyl lactate, butyl acetate, methyl methoxypropionate, ethyl ethoxypropionate, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol- 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, isoamylphosphate Propionate, isoamyl isobutyrate, di-isopentyl ether, ethylene carbonate, propylene carbonate, and the like. These may be used alone or in combination of two or more.

The solid concentration of the liquid crystal aligning agent of the present invention (the ratio of the total weight of components other than the solvent of the liquid crystal aligning agent to the total weight of the liquid crystal aligning agent) is appropriately selected in consideration of viscosity, volatility, etc., 1 to 10% by weight. That is, the liquid crystal aligning agent of the present invention is applied to the surface of the substrate as described later, and preferably is heated to form a coating film which becomes a liquid crystal alignment film or a liquid crystal alignment film. At this time, when the solid concentration is less than 1% by weight, the film thickness of the coating film becomes too small to obtain a good liquid crystal alignment film. On the other hand, when the solid concentration exceeds 10% by weight, the film thickness of the coating film becomes excessively large and it becomes difficult to obtain a good liquid crystal alignment film, and the viscosity of the liquid crystal aligning agent is increased and the coating property is deteriorated.

A particularly preferable range of the solid concentration is different depending on the method used when the liquid crystal aligning agent is applied to the substrate. For example, in the case of the spinner method, 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, it is particularly preferable to set the solid concentration in the range of 3 to 9% by weight and the solution viscosity in the range of 12 to 50 mPa · s accordingly. In the case of the inkjet method, it is particularly preferable that the solid concentration is in the range of 1 to 5 wt%, and the solution viscosity is in the range of 3 to 15 mPa · s.

The temperature for preparing the liquid crystal aligning agent of the present invention is preferably 10 to 50 占 폚, more preferably 20 to 30 占 폚.

<Liquid Crystal Alignment Film and Liquid Crystal Display Device>

The liquid crystal alignment film of the present invention is formed by the above liquid crystal aligning agent. Further, the liquid crystal display element of the present invention comprises a liquid crystal alignment film formed using the above liquid crystal aligning agent. The operation mode of the liquid crystal display element of the present invention is not particularly limited and can be applied to various driving methods such as IPS type, TN type, STN type, FFS type, VA type, OCB type, and the like.

The liquid crystal display element of the present invention can be produced, for example, by the following steps (1) to (3). In the step (1), the substrate to be used differs depending on a desired operation mode. Steps (2) and (3) are common to each operation mode.

[Process (1): Formation of coating film]

First, the liquid crystal aligning agent of the present invention is coated on a substrate, and then a coated film is formed on the substrate by heating the coated surface.

(1-1) For example, in the case of producing a TN type, STN type or VA type liquid crystal display device, first, two substrates on which a patterned transparent conductive film is formed are paired, The liquid crystal aligning agent of the present invention is preferably applied by an offset printing method, a spin coating method, a roll coater method or an inkjet printing method, respectively. Examples of the substrate include glass such as float glass and soda glass; A transparent substrate made of plastic such as polyethylene terephthalate, polybutylene terephthalate, polyether sulfone, polycarbonate, and poly (alicyclic olefin) can be used. As the transparent conductive film to be formed on one surface of the substrate, an ITO film made of NESA film (a registered trademark of PPG Corporation of the US) or indium oxide-tin oxide (In ₂ O ₃ -SnO ₂ ) made of tin oxide (SnO ₂ ) . In order to obtain a patterned transparent conductive film, for example, a method of forming a pattern by photoetching after forming a pattern-free transparent conductive film, a method of using a mask having a desired pattern for forming a transparent conductive film, and the like . When applying the liquid crystal aligning agent, a functional silane compound, a functional titanium compound or the like is preferably added to the surface of the substrate on which the coating film should be formed in order to further improve the adhesion between the substrate surface and the transparent conductive film and the coating film The pre-treatment for pre-coating may be carried out.

Preheating (prebaking) is preferably performed for the purpose of preventing the liquid flow of the applied liquid crystal aligning agent after application of the liquid crystal aligning agent. The prebaking temperature is preferably 30 to 200 캜, more preferably 40 to 150 캜, particularly preferably 40 to 100 캜. The prebaking time is preferably 0.25 to 10 minutes, more preferably 0.5 to 5 minutes. Thereafter, the solvent is completely removed, and a baking (post-baking) step is carried out for the purpose of thermally modifying the acid structure present in the polymer as required. The firing temperature (post-baking temperature) at this time is preferably 80 to 300 占 폚, more preferably 120 to 250 占 폚. The post baking time is preferably 5 to 200 minutes, more preferably 10 to 100 minutes. The film thickness of the film thus formed is preferably 0.001 to 1 占 퐉, and more preferably 0.005 to 0.5 占 퐉.

(1-2) In the case of manufacturing an IPS type liquid crystal display element, on the surface of the substrate on which the transparent conductive film patterned in the comb shape is formed, and the opposite substrate on which the conductive film is not formed, And an orientation agent are then applied, and then each coating surface is heated to form a coating film. The material, the coating method, the heating conditions after application, the patterning method of the transparent conductive film, the pretreatment of the substrate, and the preferable film thickness of the coating film to be formed are the same as those in the above (1-1).

In both cases (1-1) and (1-2), a coating film to be an alignment film is formed by applying a liquid crystal aligning agent on a substrate and then removing the organic solvent. At this time, when the polymer contained in the liquid crystal aligning agent of the present invention is a polyamic acid or an imidized polymer having an imidazole ring structure and an arboric acid structure, the dehydration ring-closure reaction is further advanced by further heating after forming the coating film, Or may be a coated film.

[Process (2): rubbing treatment]

In the case of producing a TN type, STN type or IPS type liquid crystal display device, the coating film formed in the step (1) is subjected to a rubbing treatment in which a cloth made of fibers such as nylon, rayon and cotton is rubbed in a certain direction . Accordingly, the alignment ability of the liquid crystal molecules is imparted to the coating film to form a liquid crystal alignment film.

On the other hand, in the case of manufacturing a VA type liquid crystal display device, the coating film formed in the above step (1) can be directly used as a liquid crystal alignment film, but the coating film may be rubbed.

The liquid crystal alignment layer formed as described above may be subjected to a treatment for changing a pretilt angle of a part of the liquid crystal alignment layer by irradiating a part of the liquid crystal alignment layer with ultraviolet rays or a process for forming a resist film on a part of the surface of the liquid crystal alignment layer, And then the resist film is removed so that the liquid crystal alignment film has a different liquid crystal aligning ability for each region. In this case, it is possible to improve the visual field characteristic of the obtained liquid crystal display element.

Further, a liquid crystal alignment film suitable for VA type liquid crystal display elements can be suitably used for liquid crystal display devices of the PSA (polymer sustained alignment) type.

[Process (3): Construction of liquid crystal cell]

The liquid crystal alignment layers of the two substrates are opposed to each other with a gap (cell gap) interposed therebetween such that the rubbing directions of the two liquid crystal alignment layers are orthogonal or anti-parallel to the pair of substrates on which the liquid crystal alignment layer is formed as described above, Is sealed with a sealant, liquid crystal is injected and filled in the cell gap defined by the surface of the substrate and the sealant, and the injection port is sealed to constitute the liquid crystal cell. A liquid crystal display element can be obtained by joining a polarizing plate on the outer surface of the liquid crystal cell so that the polarizing direction thereof coincides with or orthogonal to the rubbing direction of the liquid crystal alignment film formed on each substrate.

As the sealing agent, for example, an epoxy resin containing a curing agent and an aluminum oxide spheres as a spacer can be used.

Examples of the liquid crystal include nematic liquid crystals and smectic liquid crystals. Of these, nematic liquid crystals are preferable, and examples thereof include a cypher base liquid crystal, an agar watch liquid crystal, a biphenyl liquid crystal, a phenyl cyclohexane liquid crystal, , Terphenyl-based liquid crystals, biphenylcyclohexane-based liquid crystals, pyrimidine-based liquid crystals, dioxane-based liquid crystals, bicyclooctane-based liquid crystals, quaternary type liquid crystals and the like. Further, to these liquid crystals, for example, cholesteric liquid crystals such as cholesteryl chloride, cholesteryl nonanoate and cholesteryl carbonate; A chiral agent sold under the trade names of "C-15" and "CB-15" (manufactured by Merck), a strong dielectric liquid crystal such as p-decyloxybenzylidene-p- May be added and used.

Examples of the polarizing plate bonded to the outer surface of the liquid crystal cell include a polarizing plate in which a polarizing film called "H film" in which iodine is absorbed while polyvinyl alcohol is oriented in a stretched state is sandwiched between cellulose acetate protective films or a polarizing plate made of H film itself have.

The liquid crystal display element of the present invention may be a liquid crystal alignment film formed by using the liquid crystal aligning agent of the present invention and may include a retardation film having a liquid crystal alignment film for a retardation film. In this case, the liquid crystal display element of the present invention may be provided between the polarizing plate on the back side (backlight side) and the liquid crystal cell, or may be provided between the viewing side polarizing plate and the liquid crystal cell Or both of them may be provided. Such a retardation film can be obtained by, for example, applying a liquid crystal aligning agent of the present invention onto a substrate such as a cellulose acetate protective film or a polarizing film to form a coating film, and then rubbing treatment if necessary to form a liquid crystal alignment film for a retardation film And then applying a polymerizable liquid crystal to the surface of the film to cure the film.

The liquid crystal display element of the present invention can be effectively applied to various apparatuses and can be applied to various devices such as a clock, a portable game, a word processor, a notebook type personal computer, a car navigation system, a camcorder, a PDA, , Smart phones, various monitors, liquid crystal televisions, information displays, and the like.

Example

Hereinafter, the present invention will be described more specifically by way of examples, but the present invention is not limited to these examples.

The solution viscosity of each polymer solution and the imidization rate of the polyimide in the synthesis examples were measured by the following methods.

[Solution viscosity of polymer solution]

The solution viscosity (mPa 占 퐏) of the polymer solution was measured at 25 占 폚 using an E-type rotational viscometer for a solution adjusted to a polymer concentration of 10% by weight using a predetermined solvent.

[Imidization Rate of Polyimide]

The polyimide solution was poured into pure water, and the obtained precipitate was sufficiently dried under reduced pressure at room temperature, then dissolved in deuterated dimethyl sulfoxide, and ¹ H-NMR was measured at room temperature using tetramethylsilane as a reference material. From the obtained ¹ H-NMR spectrum, the imidization ratio [%] was determined by the equation shown in the following formula (1).

Imidization rate [%] = ((1-A ¹ ) / (A ² × α)) × 100 (One)

(In the formula (1), A ¹ is the peak area derived from the proton of the NH group near the chemical shift of 10 ppm, A ² is the peak area derived from the other proton, and α is the peak area derived from the proton The ratio of the number of other protons to one proton in the NH group).

<Synthesis of diamine>

In the following Synthesis Examples, the necessary amounts of the following polymerization examples were secured by repeating the polymerization at the following scales as necessary.

Synthesis Example 1: Synthesis of compound (a-1-1)

(A-1-1) represented by the following formula (A-1-1) was synthesized according to Reaction Scheme 1 below.

31 g of 4-fluoronitrobenzene, 10 g of 4-aminopiperidine, 18.5 g of sodium hydrogencarbonate and 200 mL of ethanol were mixed in a 1 L three-necked flask equipped with a stirrer, a nitrogen inlet tube and a thermometer and stirred at 80 ° C for 4 hours did. After completion of the reaction, the reaction solution was dissolved in ethyl acetate, and the solution was separated and washed with distilled water. Subsequently, the organic layer was dried with magnesium sulfate and concentrated, and the obtained solid was washed with ethanol to obtain 26 g of a crystal of the compound (a-1). Next, 25 g of the compound (a-1), 99 g of zinc, 16 g of ammonium chloride, 300 mL of THF and 50 mL of ethanol were mixed in a 1 L three-necked flask under nitrogen atmosphere, 40 mL of distilled water was added dropwise while stirring in an ice bath, C &lt; / RTI &gt; for 4 hours. After removing zinc and the like by filtration, the solution was dissolved in ethyl acetate, and the solution was separated and washed with distilled water. The organic layer was then dried over magnesium sulfate and concentrated to give a brown powder. Recrystallization was performed with 100 mL of ethyl acetate and 200 mL of hexane to obtain 17 g of a crystal of the compound (a-1-1) represented by the following formula (A-1-1).

[Synthesis Example 2: Synthesis of compound (a-1-3)] [

(A-1-3) represented by the following formula (A-1-3) was synthesized according to the following Reaction Scheme 2.

15.5 g of 4-fluoronitrobenzene, 10 g of 4-hydroxypiperidine, 9.2 g of sodium hydrogencarbonate and 100 mL of ethanol were mixed in a 1 L three-necked flask equipped with a stirrer, a nitrogen inlet tube and a thermometer, Stirring time. After completion of the reaction, the reaction solution was dissolved in ethyl acetate, and the solution was separated and washed with distilled water. The organic layer was dried with magnesium sulfate and concentrated, and the obtained solid was recrystallized from ethanol to obtain 20 g of a crystal of the compound (a-2). Subsequently, 19 g of the compound (a-2), 13 g of triethylamine and 150 mL of THF were mixed in a 500 mL three-necked flask under nitrogen atmosphere, and 16 g of 4-nitrobenzoyl chloride was dissolved in 50 mL of THF while stirring in an ice bath. , And the mixture was stirred at 20 ° C for 1 hour. After completion of the reaction, the reaction solution was dissolved in ethyl acetate, and the solution was separated and washed with distilled water. The organic layer was dried with magnesium sulfate and concentrated, and the obtained solid was recrystallized from ethanol to obtain 25 g of a crystal of the compound (a-3). Finally, 24.5 g of the compound (a-3), 87 g of zinc, 14 g of ammonium chloride, 300 mL of THF and 50 mL of ethanol were mixed in a 500 mL three-necked flask under nitrogen atmosphere. 35 mL of distilled water was added dropwise while stirring in an ice bath, Followed by stirring at 20 占 폚 for 5 hours. After removing zinc and the like by filtration, the solution was dissolved in ethyl acetate, and the solution was separated and washed with distilled water. The organic layer was dried with magnesium sulfate and concentrated, and the resulting powder was recrystallized from 100 mL of ethyl acetate and 200 mL of hexane to obtain 19 g of a crystal of the compound (a-1-3).

[Synthesis Example 3: Synthesis of compound (a-1-5)] [

Compound (a-1-5) represented by the following formula (A-1-5) was synthesized according to the following Reaction Scheme 3.

31 g of 4-fluoronitrobenzene, 36 g of cesium fluoride, 26 g of isonipecotic acid and 200 mL of dimethylsulfoxide were mixed in a 1 L three-necked flask equipped with a stirrer, a nitrogen inlet tube and a thermometer, Lt; / RTI &gt; After completion of the reaction, 400 mL of distilled water was mixed, and the precipitated powder was recovered by filtration. Washed thoroughly with distilled water and hexane, and dried to obtain 44 g of a compound (a-4). Next, 25 g of the compound (a-4), 13 g of 4-nitrophenol, 23 g of 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride (EDC) and 350 mL of THF were mixed, 2.5 g of aminopyridine was added, followed by stirring at 20 占 폚 for 4 hours. After completion of the reaction, the reaction solution was dissolved in ethyl acetate, and liquid separation was carried out with distilled water. The organic layer was dried with magnesium sulfate and concentrated, and the obtained solid was washed with ethanol to obtain 24 g of a crystal of the compound (a-5). Lastly, 24 g of the compound (a-5), 85 g of zinc, 14 g of ammonium chloride, 300 mL of THF and 50 mL of ethanol were mixed in a 500 mL three-necked flask under nitrogen atmosphere, 35 mL of distilled water was added dropwise while stirring in an ice bath, C &lt; / RTI &gt; for 5 hours. After removing zinc and the like by filtration, the solution was dissolved in ethyl acetate, and the solution was separated and washed with distilled water. The organic layer was dried with magnesium sulfate and concentrated. The resulting powder was redissolved in THF and filtered through celite. The filtrate was concentrated to obtain 16 g of a powder of the compound (a-1-5).

[Synthesis Example 4: Synthesis of compound (a-1-6)] [

Compound (a-1-6) represented by the following formula (A-1-6) was synthesized according to the following Reaction Scheme 4.

15 g of the compound (a-4) obtained in the same manner as in Synthesis Example 3, 8.35 g of 3-nitrophenol, 13.8 g of 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide hydrochloride (EDC) , And 1.47 g of dimethylaminopyridine was added thereto while stirring in an ice bath, followed by stirring at 20 ° C for 6 hours. After completion of the reaction, the reaction solution was dissolved in ethyl acetate, and liquid separation was carried out with distilled water. The organic layer was dried over magnesium sulfate, and the obtained solid was washed with ethanol to obtain 17.9 g of a crystal of the compound (a-6). Finally, 17.9 g of the compound (a-6), 63.2 g of zinc, 10.3 g of ammonium chloride, 210 mL of THF and 30 mL of ethanol were mixed in a 500 mL three-necked flask under nitrogen atmosphere and 24 mL of distilled water was added dropwise while stirring in an ice bath After that, the mixture was stirred at 20 占 폚 for 7 hours. After removing zinc and the like by filtration, the solution was dissolved in ethyl acetate, and the solution was separated and washed with distilled water. The organic layer was dried with magnesium sulfate and concentrated. The resulting powder was redissolved in THF and filtered through celite. The filtrate was concentrated, and the resulting solid was recrystallized from THF and hexane to obtain 13 g of the compound (a-1-6).

<Synthesis of polyimide>

[Polymerization Example 1]

0.5 mol (11.2 g) of 2,3,5-tricarboxycyclopentyl acetic acid dianhydride (TCA) as tetracarboxylic dianhydride, 0.1 mol (52.3 g) of 3,5-diaminobenzoic acid cholestanil as a diamine, 0.05 mol (24.8 g) of cholestanyloxy-2,4-diaminobenzene, 0.025 mol (0.78 g) of the compound (a-1-5) and 0.325 mol -2-pyrrolidone (NMP), and the reaction was carried out at 60 DEG C for 6 hours to obtain a solution containing 20 wt% of polyamic acid. A small amount of this solution was taken and N-methyl-2-pyrrolidone was added to prepare a solution having a weight of 10% by weight of polyamic acid. The viscosity of the solution measured at 25 캜 was 60 mPa..

Subsequently, 130 g of NMP was added to the obtained polyamic acid solution, 2.4 g of pyridine and 3.1 g of acetic anhydride were added, and the dehydration ring-closure reaction was carried out at 110 DEG C for 4 hours. After the dehydration ring closure reaction, the solvent in the system was replaced with a solvent by a new NMP (by removing the pyridine and the anhydrous acetic acid used in the dehydration ring closure reaction out of the system by the solvent substitution reaction, the same applies hereinafter), polyimide having an imidation rate of 46% PI-1) in an amount of 20% by weight. A small amount of this solution was added to NMP to prepare a solution having a polyimide concentration of 10% by weight, and the solution viscosity measured at 25 캜 was 55 mPa..

[Polymerization Examples 2 to 9, Comparative Polymerization Examples 1 and 2]

Except that the kind and amount of tetracarboxylic acid dianhydride and diamine used were changed as shown in Table 1 and the amount of pyridine and acetic anhydride used was changed as shown in Table 1 below, (PI-2) to (PI-11) were synthesized, respectively. The reaction solution was prepared by adding NMP so that the total amount of the tetracarboxylic acid dianhydride and the diamine was 20% by weight based on the total amount of the reaction solution.

<Synthesis of polyamic acid>

[Polymerization Example 10]

0.45 mol (5.6 g) of 1,2,3,4-cyclobutane tetracarboxylic acid dianhydride and 0.05 mol (0.7 g) of 1,2,4,5-benzenetetracarboxylic dianhydride as tetracarboxylic dianhydrides, 0.1 mol (2.0 g) of the compound (a-1-5), 0.05 mol (1.0 g) of tetradecanoxy-2,4-diaminobenzene, 3,6-bis (4-aminobenzoyloxy) cholestane 0.29 mol (4.2 g) of 4-aminophenyl-4'-aminobenzoate and 4,4'- [4,4'-propane-1,3-diylbis (piperidin- 1,4-diyl)] dianiline (0.05 g, 1.2 g) was dissolved in 85 g of NMP and reacted at 40 ° C for 8 hours to obtain a solution containing 15% by weight of polyamic acid. A small amount of this solution was collected and NMP was added to obtain a solution having a polyamic acid concentration of 10% by weight, and the solution viscosity measured at 25 占 폚 was 80 mPa 占 퐏.

[Polymerization Examples 11 to 17, Comparative Polymerization Example 3]

(PA-2) to (PA-9) were synthesized in the same manner as in Polymerization Example 10 except that the kind and amount of tetracarboxylic acid dianhydride and diamine used were changed as shown in Table 2 below. The reaction solution was prepared by adding NMP so that the total amount of the tetracarboxylic acid dianhydride and the diamine was 15% by weight based on the total amount of the reaction solution.

The numerical values of the tetracarboxylic dianhydrides in Tables 1 and 2 indicate the content [mol%] with respect to the total amount of the tetracarboxylic dianhydride used in the synthesis, and the numerical values of the diamine were (Mol%). The numerical values of pyridine and acetic anhydride represent the content [mol%] with respect to the number of the unit of the number of the stoichiometric units of the polyamic acid.

The abbreviations of tetracarboxylic dianhydrides and diamines have the following meanings respectively.

&Lt; Tetracarboxylic acid dianhydride &gt;

J: 2,3,5-tricarboxycyclopentyl acetic acid dianhydride

K: 1,2,3,4-cyclobutane tetracarboxylic acid dianhydride

L: 1,2,4,5-benzene tetracarboxylic acid dianhydride

<Diamine>

B: Cholestanyl 3,5-diaminobenzoate

C: Cholestanyloxy-2,4-diaminobenzene

D: p-phenylenediamine

E: 3,5-diaminobenzoic acid

F: tetradecanoxy-2,4-diaminobenzene

G: 3,6-bis (4-aminobenzoyloxy) cholestane

H: 4-Aminophenyl-4'-aminobenzoate

I: 4,4 '- [4,4'-Propane-1,3-diylbis (piperidine-1,4-diyl)] dianiline

&Lt; Synthesis of epoxy group-containing compound (EPS-1) &gt;

34.48 g of 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 34.48 g of methyl isobutyl ketone and 3.45 g of triethylamine were placed in a reactor equipped with a stirrer, a thermometer, a dropping funnel and a reflux condenser, And mixed at room temperature. Then, 27.59 g of deionized water was added dropwise from the dropping funnel over 30 minutes, and the reaction was carried out at 80 DEG C for 6 hours while stirring under reflux. After completion of the reaction, the organic layer was taken out, washed with 0.2 g of an aqueous ammonium nitrate solution until the washed water became neutral, and then the solvent and water were distilled off under reduced pressure to obtain a viscous polyorganosiloxane solution . As a result of ¹ H-NMR analysis of the polyorganosiloxane, it was found that a peak based on the epoxy group was obtained in the vicinity of the chemical shift (?) = 3.2 ppm in accordance with theoretical strength, and a subsidiary reaction of the epoxy group occurred during the reaction Was confirmed. The polyorganosiloxane had a weight average molecular weight Mw of 3,000 and an epoxy equivalent of 184.8 g / mol.

7.70 g of the above-mentioned polyorganosiloxane, 44.8 g of methyl isobutyl ketone as a solvent, 3.50 g of 4'-pentyl-1,1'-bicyclohexyl-4-carbonic acid and 3.5 g of tetrabutylammonium 0.77 g of bromide was added, and the reaction was carried out at 100 占 폚 for 8 hours with stirring. After completion of the reaction, ethyl acetate was added to the reaction mixture, and the resulting solution was washed with water three times. The organic layer was dried over magnesium sulfate and the solvent was distilled off to obtain a reactive polyorganosiloxane (compound (EPS-1) 10.9 g. The weight average molecular weight Mw of the compound (EPS-1) was 8,500.

&Lt; Preparation of liquid crystal aligning agent &

[Example 1]

(1) Preparation of liquid crystal aligning agent for evaluation of printability

N-methyl-2-pyrrolidone (NMP) and butyl cellosolve (BC) were added to a solution containing 100 parts by weight of the polyimide (PI-1) obtained in Polymerization Example 1, 50: 50 (weight ratio), and a solid content concentration of 6.5% by weight. This solution was filtered using a filter having a pore diameter of 1 탆 to prepare a liquid crystal aligning agent A for evaluation of printability.

(2) Preparation of liquid crystal aligning agent for device manufacture

A liquid crystal aligning agent B for producing a device was obtained in the same manner as in the above (1) except that the solid content concentration of the solution before filtration was changed to 4.0 wt% in the above (1).

[Examples 2 to 26 and Comparative Examples 1 to 9]

A liquid crystal aligning agent A for evaluation of printability and a liquid crystal aligning agent B for producing a device were prepared in the same manner as in Example 1 except that the polymer and additives used were changed as shown in Tables 3 and 4, Respectively.

&Lt; Production of liquid crystal display element &

[Production Example 1]

The liquid crystal aligning agent B for use in the production of the device of Example 1 prepared above was coated on a transparent conductive film made of an ITO film formed on one side of a glass substrate having a thickness of 1 mm by using a spinner and baked on a hot plate at 80 DEG C for 1 minute And heated. Subsequently, the substrate was heated on a hot plate at 230 캜 for 30 minutes to form a coating film (liquid crystal alignment film) having a thickness of about 80 nm. This operation was repeated to prepare four substrates (two pairs) each having a liquid crystal alignment film.

Next, a pair of substrates having a liquid crystal alignment film was coated with an epoxy resin adhesive containing an aluminum oxide sphere having a diameter of 3.5 占 퐉 on each outer edge of a face having the liquid crystal alignment film, Are pressed against each other to cure the adhesive. Subsequently, a negative type liquid crystal (MLC-6608 manufactured by Merck Ltd.) was filled between the pair of substrates from the liquid crystal injection port, the liquid crystal injection hole was sealed with an acrylic photocurable adhesive, and a polarizing plate was bonded to both sides of the substrate, A vertical alignment type liquid crystal display element was produced.

[Production Examples 2 to 14, Comparative Production Examples 1 to 6]

A liquid crystal display element of vertical alignment type was produced in the same manner as in Production Example 1 except that the liquid crystal aligning agent to be used was changed to the liquid crystal aligning agent B for the device of Examples 2 to 14 or Comparative Examples 1 to 6 did.

[Production Example 15]

The liquid crystal aligning agent B for manufacturing an element of Example 15 prepared above was applied to a transparent conductive film made of an ITO film formed on one side of a glass substrate having a thickness of 1 mm by using a spinner and baked on a hot plate at 80 DEG C for 1 minute And heated. Subsequently, the coated film was heated on a hot plate at 230 캜 for 30 minutes to form a coating film having a film thickness of about 80 nm. The coating film was rubbed with a rubbing machine having a roll coated with a cloth made of cotton at a roll rotation speed of 600 rpm, a stage moving speed of 2 cm / sec, and a hair pressing indentation length of 0.4 mm, To give a liquid crystal alignment function, thereby forming a liquid crystal alignment film. The substrate having the liquid crystal alignment film was ultrasonically cleaned in ultrapure water for 1 minute and then dried in a 100 ° C clean oven for 10 minutes. By repeating these series of operations, two substrates (one pair) having liquid crystal alignment films were produced.

Next, a pair of substrates having a liquid crystal alignment film was coated with an epoxy resin adhesive containing an aluminum oxide sphere having a diameter of 3.5 占 퐉 on the outer edge of each of the faces having the liquid crystal alignment film, And the adhesive was cured. Subsequently, a nematic liquid crystal (MLC-6221 manufactured by Merck Ltd.) was filled between the pair of substrates from the liquid crystal injection port, the liquid crystal injection port was sealed with an acrylic photocurable adhesive, and a polarizing plate was bonded to both sides of the substrate, A horizontal alignment type liquid crystal display element was produced.

[Production Examples 16 to 26, Comparative Production Examples 7 to 9]

A horizontal alignment type liquid crystal display device was produced in the same manner as in Production Example 15 except that the liquid crystal aligning agent to be used was changed to the liquid crystal aligning agent B for producing devices of Examples 16 to 26 or Comparative Examples 7 to 9 did.

&Lt; Evaluation of liquid crystal alignment film &

(1) Evaluation of printability

The liquid crystal aligning agent A for evaluation of printability prepared as described above was subjected to a liquid crystal aligning film forming process using a liquid crystal alignment film printing machine (Angstromer type "S40L-532", manufactured by Nihon Chasin Insights Co., Ltd.) The dropping amount of the aligning agent was applied on the surface of the transparent electrode of the glass substrate having the transparent electrode made of the ITO film under the condition of 20 droplets (about 0.2 g) reciprocating. In addition, the dropping amount which is usually employed in a printing press of the same type is 30 droplets (about 0.3 g) reciprocating, and the printing conditions are set to be stricter than usual.

The substrate coated with the liquid crystal aligning agent was heated (prebaked) on a hot plate at 80 DEG C for 1 minute and then heated on a hot plate at 180 DEG C for 10 minutes (post baking) to form a coating film having a thickness of 80 nm. This coating film was observed under a microscope with a magnification of 20 times to examine whether the liquid crystal aligning agent was uneven or not. In the evaluation, the case where there was no unevenness of coating and the case where the unevenness of coating was observed was evaluated as &quot; good &quot;, the case where the unevenness of coating was slightly observed and the case where the unevenness of coating were clearly observed were evaluated as & . The results are shown in Tables 3 and 4.

(2) Evaluation of reworkability

A liquid crystal aligning agent B for use in the production of the device prepared above was applied by a spinner on a transparent conductive film made of an ITO film formed on one side of a glass substrate having a thickness of 1 mm and prebaked at 100 DEG C for 90 seconds on a hot plate, A coating film having a film thickness of about 80 nm was formed. This operation was repeated to prepare four substrates having a coating film. Subsequently, the obtained substrate was stored in a dark room at 25 캜 in a nitrogen atmosphere, and taken out after 12 hours, 24 hours, 48 hours, and 72 hours, respectively, and immersed in a beaker containing NMP at 40 캜 for 2 minutes. After 2 minutes, the substrate was taken out from the beaker, washed several times with ultra-pure water, and then water droplets were removed from the surface with an air blow, the substrate was observed, and the remaining state of the coating film was observed with an optical microscope. The evaluation was made based on the fact that the coated film remained on the substrate having the storage time of 72 hours and that the peeling was possible on the substrate having the storage time of 48 hours, , It was found that the reworkability was "possible" and that the coating film could not be peeled off even on a substrate having a storage time of 12 hours. Poor work &quot;. The evaluation results are shown in Tables 3 and 4.

&Lt; Evaluation of liquid crystal display element &

(1) Evaluation of Initial Voltage Conservation Rate

A voltage of 5 V was applied to the liquid crystal display element immediately after the manufacture at a temperature of 60 캜 for an application time of 60 microseconds and a span of 167 milliseconds and then a voltage maintenance ratio (initial voltage maintenance ratio) of 167 milliseconds was measured from the application of the release. VHR-1 &quot; manufactured by Toyo Technica Co., Ltd. was used. The results are shown in Tables 3 and 4 below.

(2) Evaluation of light resistance

One side of the liquid crystal display element after the initial voltage holding ratio VH ₁ was measured was irradiated with light for 1000 hours using a weather meter having a carbon arc as a light source. The voltage holding ratio of the liquid crystal cell after light irradiation was measured by the same method as described above. When this value was the voltage holding ratio VH ₂ after light irradiation and the initial voltage holding ratio was VH ₁ , the decrease amount of the voltage holding ratio obtained by subtracting VH ₂ from VH ₁ was designated as? VHR, and the light resistance was evaluated by? VHR. The measurement results are shown in Tables 3 and 4 below.

(3) Evaluation of high temperature and high humidity resistance

The other side of the liquid crystal display element after the initial voltage holding ratio VH ₁ was measured was stored in an oven set at 60 ° C and a humidity of 90% for 300 hours, and the voltage holding ratio was measured in the same manner as described above. The high-temperature and high-humidity resistance was evaluated by? VHR 'with the amount of decrease of the voltage holding ratio obtained by subtracting VH ₄ from VH ₃ when the voltage holding ratio after stressing was VH ₄ and the initial voltage holding ratio was VH ₃ . The measurement results are shown in Tables 3 and 4 below.

In Table 3 and Table 4, the numerical values of the additive represent the content [parts by weight] of the liquid crystal aligning agent with respect to 100 parts by weight of the polymer. The abbreviations of the additives are as follows.

M: N, N, N ', N'-tetraglycidyl-m-xylylenediamine

N: TINUVIN 622 (amine antioxidant)

O: Compound (EPS-1)

P: dipentaerythritol hexaacrylate

Q: N, N, N ', N'-tetraglycidyl-4,4'-diaminodiphenylmethane

As shown in Tables 3 and 4, in the liquid crystal display device manufactured using the liquid crystal aligning agent of the examples, the voltage holding ratio in the case of being exposed under an environment of light irradiation, high temperature and high humidity, , And was excellent in light resistance and high temperature and high humidity resistance. In addition, both the peelability (reworkability) and the printability of the substrate were good.

On the other hand, in the comparative example, at least either of? VHR and? VHR 'was larger than that of the examples in each of the polyimide type and polyamic acid type, and the light resistance and high temperature and high humidity resistance were deteriorated.

Claims (9)

1. A liquid crystal aligning agent comprising at least one polymer selected from the group consisting of a polyamic acid obtained by reacting a tetracarboxylic acid dianhydride with a diamine and a polyimide obtained by dehydrocondylating the polyamic acid,
The liquid crystal aligning agent according to claim 1, wherein the diamine comprises a compound (a) represented by the following formula (A)

Only, Am ^1; (formula (A) of, Am ¹ is, and with pyrrolidine dinhwan, piperidin dinhwan or 2 to form a hexamethylene yiminhwan monovalent group with the nitrogen atom, may optionally have a substituent are bonded to these ring parts in, bonded to the nitrogen atom constituting the ring, and X ^2, which may; X ¹ is a single bond, an oxygen atom, a carbonyl group, * -COO-, * -OCO-, -NH- , * -Ar 1 -O-, -O-Ar ¹ -, -COO-Ar ¹ -, or * -R ³ -OCO- (wherein Ar ¹ is a bivalent group having a phenylene group or a phenylene group bonded to a substituent and R ³ is a carbon number 1 or 2 alkanediyl group, and in; "*" indicates the bonding hands of the nitrogen-containing heterocyclic ring) and; X ² is a single bond or carbonyl group; and R ¹ is a monovalent organic group, r is each Independently, an integer of 0 to 4, provided that when the sum of r is 2 or more, plural R ¹ independently have the above definition). The method according to claim 1,
The compound (a) is a liquid crystal aligning agent represented by the following formula (A-1)

, X ¹ (wherein (A-1) is a single bond, an oxygen atom, a carbonyl group, * -COO-, * -OCO-, -NH- , * -Ar 1 -O-, * -O-Ar 1 -, -COO-Ar ¹ -, or -R ³ -OCO- (wherein Ar ¹ is a bivalent group having a phenylene group or a phenylene group bonded to a substituent and R ³ is an alkanediyl group having 1 or 2 carbon atoms and; "*" indicates the bonding hands of the nitrogen-containing heterocyclic ring) and; X ² is a single bond or a carbonyl group and; r ¹ and r ⁴ are each independently a monovalent organic group, r and s are Independently of one another, with the proviso that when the sum of r is 2 or more, plural R ¹ independently have the above definition, and when s is 2 or more, plural R ⁴ independently have the above definition) . 3. The method according to claim 1 or 2,
And X ² is a single bond. 3. The method according to claim 1 or 2,
Wherein X ¹ is * -COO-, * -OCO-, -NH- or * -R ³ -OCO- (wherein R ³ is an alkanediyl group having 1 or 2 carbon atoms, * is a nitrogen-containing heterocyclic ring And a liquid crystal aligning agent. 3. The method according to claim 1 or 2,
Wherein the tetracarboxylic acid dianhydride is at least one selected from the group consisting of 2,3,5-tricarboxycyclopentylacetic acid dianhydride and 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride. Orientation agent. A liquid crystal alignment film formed using the liquid crystal aligning agent according to claim 1 or 2. A liquid crystal display element comprising the liquid crystal alignment film according to claim 6. A polymer obtained by reacting a diamine containing a compound (a) represented by the following formula (A) with a tetracarboxylic acid dianhydride:

Only, Am ^1; (formula (A) of, Am ¹ is, and with pyrrolidine dinhwan, piperidin dinhwan or 2 to form a hexamethylene yiminhwan monovalent group with the nitrogen atom, may optionally have a substituent are bonded to these ring parts in, bonded to the nitrogen atom constituting the ring, and X ^2, which may; X ¹ is a single bond, an oxygen atom, a carbonyl group, * -COO-, * -OCO-, -NH- , * -Ar 1 -O-, -O-Ar ¹ -, -COO-Ar ¹ -, or * -R ³ -OCO- (wherein Ar ¹ is a bivalent group having a phenylene group or a phenylene group bonded to a substituent and R ³ is a carbon number 1 or 2 alkanediyl group, and in; "*" indicates the bonding hands of the nitrogen-containing heterocyclic ring) and; X ² is a single bond or carbonyl group; and r ¹ is a monovalent organic group, r is each Independently, an integer of 0 to 4, provided that when the sum of r is 2 or more, plural R ¹ independently have the above definition). delete