WO2017043822A1

WO2017043822A1 - Polymer for liquid crystal alignment agent

Info

Publication number: WO2017043822A1
Application number: PCT/KR2016/009916
Authority: WO
Inventors: 조정호; 박항아; 한희; 권순호; 윤준영; 윤형석
Original assignee: 주식회사 엘지화학
Priority date: 2015-09-08
Filing date: 2016-09-05
Publication date: 2017-03-16
Also published as: KR101835746B1; KR20170030045A; WO2017043822A8

Abstract

The present invention relates to a polymer for a liquid crystal alignment agent, a liquid crystal alignment agent comprising the same, a liquid crystal alignment film formed from the liquid crystal alignment agent, and a liquid crystal display device comprising the same. The polymer effectively inhibits a decomposition reaction of a polymer during a calcination process or storage for forming a liquid crystal alignment film, exhibits excellent coating properties at the time of coating, exhibits a high conversion rate to imide during the calcination process, and may provide a liquid crystal alignment agent having superior orientation stability and electrical characteristics.

Description

【Specification】

[Name of invention]

Polymer for Liquid Crystal Alignment

Technical Field

Cross Citation with Related Application (s)

This application claims the benefit of priority based on Korean Patent Application No. 10-2015-0127042 of September 8, 2015 and Korean Patent Application No. 10-2016-0113223 of September 2, 2016, and the documents of those Korean patent applications All content disclosed in is included as part of this specification.

The present invention relates to a polymer suitable for use in a liquid crystal aligning agent, a liquid crystal aligning agent comprising the same, a liquid crystal aligning film formed from the liquid crystal aligning agent, and a liquid crystal display element comprising the liquid crystal aligning film.

Background Art

In the liquid crystal display device, the liquid crystal alignment film plays a role of orienting the liquid crystal in a constant direction. Specifically, the liquid crystal alignment layer serves as a director in the arrangement of the liquid crystal molecules so that the liquid crystal is moved by an electric field to form an image when the liquid crystal is moved to form an image. In general, in order to obtain uniform brightness and high contrast rat io in the liquid crystal display, it is essential to orient the liquid crystal uniformly.

As a conventional method of aligning the liquid crystal, a rubbing method is used in which a polymer film such as polyimide is applied to a substrate such as glass and the surface is rubbed in a predetermined direction using fibers such as nylon or polyester. However, the rubbing method may generate fine dust or electrostatic discharge (ESD) when the fiber and the polymer film are rubbed, which may cause serious problems in manufacturing the liquid crystal panel.

In order to solve the problem of the rubbing method, in recent years, a photo-alignment method of inducing anisotropy (anisotropy, ani sotropy) to a polymer film by light irradiation instead of friction and arranging liquid crystals using the same has been studied.

As a material that can be used in the photo-alignment method, various materials have been introduced, and among them, polyamic acid is added for good overall performance of the liquid crystal alignment layer. Mainly used. However, the polyamic acid has a problem in that it is difficult to provide a stable ^' liquid crystal alignment film by polymer decomposition reaction due to a reversible reaction during a baking process or storage for forming a liquid crystal alignment film.

[Content of invention]

[Problem to solve]

The present invention provides a polymer capable of providing a liquid crystal aligning agent that suppresses polymer degradation reaction in the firing step of a liquid crystal alignment film with an excessive amount of S and exhibits high imide conversion.

This invention also provides the liquid crystal aligning agent containing the said polymer, the liquid crystal aligning film formed from the said liquid crystal aligning agent, and the liquid crystal display element containing the said liquid crystal aligning film.

[Measures of problem]

Hereinafter, a polymer for a liquid crystal aligning agent, a liquid crystal aligning agent including the polymer, a method of forming a liquid crystal aligning film using the liquid crystal aligning agent, a liquid crystal display device including the liquid crystal aligning film, and the like according to a specific embodiment of the present invention will be described. do.

According to an embodiment of the present invention, a repeating unit represented by the following formula (1), a repeating unit represented by the following formula (2), and a repeating unit represented by the following formula (3), the total repeating unit represented by the following formula (1) With respect to the polymer for a liquid crystal aligning agent comprising a repeating unit represented by the following formula (1) to 1 to 30 moles ¾>.

[Formula 1]

[Formula 3]

In Chemical Formulas 1 to 3,

X ¹ to X ³ are each independently a tetravalent organic group derived from a hydrocarbon having 4 to 20 carbon atoms, at least one H of the tetravalent organic groups is substituted with halogen, or at least one -CH ₂ -valent oxygen or sulfur A tetravalent organic group substituted with -0-, -CO-, -S-, -SO-, -S0 ₂ -or -C0NH- so that atoms are not directly connected,

R ¹ and R ² are each independently hydrogen or an alkyl group having 1 to 10 carbon atoms, and both R ¹ and R ² are not hydrogen,

γ ^ΐ to γ ³ are each independently a divalent organic group represented by the following formula (4),

[

In Chemical Formula 4,

R ³ and R ⁴ are each independently halogen, cyano group, alkyl group having 1 to 10 carbon atoms, alkenyl group having 2 to 10 carbon atoms, alkoxy group having 1 to 10 carbon atoms, fluoroalkyl group having 1 to 10 carbon atoms or 1 to 10 carbon atoms A fluoroalkoxy group of 10, ρ and q are each independently an integer between 0 and 4,

L ¹ is a single bond, -0-, -CO-, -S-, -S0 _2- , -C (CH ₃ ) ₂ —, -C (CF ₃ ) _2- , -C0NH-, -C00-,- (C¾) _z- ， -0 (CH ₂ ) _z 0-, -0 (CH ₂ ) _z- , -0CH ₂ -C (CH ₃ ) ₂ -CH ₂ 0- or -C00- (CH ₂ ) _z- 0C0-,

Z is an integer between 1 and 10,

m is an integer between 0 and 3.

Unless otherwise specified herein, the following terms may be defined as follows. Hydrocarbons having 4 to 20 carbon atoms include alkanes having 4 to 20 carbon atoms, alkenes having 4 to 20 carbon atoms, alkynes having 4 to 20 carbon atoms, cycloalkanes having 4 to 20 carbon atoms, and carbon atoms. A cycloalkene of 4 to 20, an arene of 6 to 20 carbon atoms, or black, a fused ring in which at least one cyclic hydrocarbon shares two or more atoms, or one of them At least one hydrocarbon may be a hydrocarbon bonded chemically. Specifically, hydrocarbons having 4 to 20 carbon atoms include n-butane, cyclobutane, 1-methylcyclobutane, 1,3-dimethylcyclobutane, 1,2,3,4-tetramethylcyclobutane, cyclopentane and cyclonucleic acid. , Cycloheptane cyclooctane, cyclonuxene, 1-methyl-3-ethylcyclonuxene, bicyclonuclear chamber, benzene, biphenyl, diphenylmethane, 2, 2-diphenylpropane, 1-ethyl -1, 2, 3 4-tetrahydronaphthalene, 1, 6- diphenylnucleic acid, etc. can be illustrated.

The alkyl group having 1 to 10 carbon atoms may be a straight chain, branched chain or cyclic alkyl group. Specifically, the alkyl group having 1 to 10 carbon atoms is a straight chain alkyl group having 1 to 10 carbon atoms; Linear alkyl groups having 1 to 5 carbon atoms; Branched or cyclic alkyl groups having 3 to 10 carbon atoms; Or a branched or cyclic alkyl group having 3 to 6 carbon atoms. More specifically, the alkyl group having 1 to 10 carbon atoms includes methyl group, ethyl group, n—propyl group, i so-propyl group, n-butyl group, isobutyl group, tert-butyl group, n_pentyl group, i so- A pentyl group, neo-pentyl group, a cyclonuclear group, etc. can be illustrated.

The alkoxy group having 1 to 10 carbon atoms may be a straight chain, branched chain or cyclic alkoxy group. Specifically, the alkoxy group having 1 to 10 carbon atoms is a straight alkoxy group having 1 to 10 carbon atoms; Linear alkoxy groups having 1 to 5 carbon atoms; Branched or cyclic alkoxy groups having 3 to 10 carbon atoms; Or a branched or cyclic alkoxy group having 3 to 6 carbon atoms. More specifically, examples of the alkoxy group having 1 to 10 carbon atoms include meso groups, epoxy groups, n-propoxy groups, i so—propoxy groups, n-subspecial groups, i so_butoxy groups, tert-butoxy groups, n-pentoxy groups , I so-pentoxy group, neo_phenoxy group, cyclonuclear special group, etc. can be illustrated.

The fluoroalkyl group having 1 to 10 carbon atoms may be substituted with fluorine at least one hydrogen of the alkyl group having 1 to 10 carbon atoms, and the fluoroalkoxy group having 1 to 10 carbon atoms may have at least one alkoxy group having 1 to 10 carbon atoms. Hydrogen may be substituted with fluorine.

Alkenyl groups having 2 to 10 carbon atoms may be linear, branched or cyclic alkenyl groups. Specifically, an alkenyl group having 2 to 10 carbon atoms has a straight chain alkenyl group having 2 to 10 carbon atoms, a straight chain alkenyl group having 2 to 5 carbon atoms, a branched alkenyl group having 3 to 10 carbon atoms, a branched alkenyl group having 3 to 6 carbon atoms, and a carbon number It may be a cyclic alkenyl group of 5 to 10 or a cyclic alkenyl group of 6 to 8 carbon atoms. More specifically, examples of the alkenyl group having 2 to 10 carbon atoms include an ethenyl group, propenyl group, butenyl group, pentenyl group or cyclonuxenyl group.

Halogen may be fluorine (F), chlorine (C1), bromine (Br) or iodine (I),

A mult ivalent organi c group derived from any compound means a moiety in the form in which a plurality of hydrogen atoms attached to any compound have been removed. For example, a tetravalent organic group derived from cyclobutane means a moiety in a form in which any four hydrogen atoms bonded to cyclobutane are removed.

In the present specification, ᅳ * in the formula means a residue of a form in which hydrogen of the site is removed. For example, * ^ ᅳ * means any one of residues in the form of four hydrogen atoms bonded to carbons 1, 2, 3, and 4 of cyclobutane, that is, a tetravalent organic group derived from cyclobutane. .

Conventional liquid crystal alignment films were prepared by coating and firing polyamic acid. However, polyamic acid may cause polymer degradation reaction due to reversible reaction during heat treatment, and there is a problem such that molecular weight decreases due to decomposition reaction of polyamic acid during storage. In order to solve this problem, polyamic acid ester was used as the liquid crystal alignment layer material, but the polyamic acid ester had a problem that the imide conversion rate was very low during the firing process, thereby providing a reliable liquid crystal alignment layer.

Thus, the inventors of the present invention, through the experiment, when using the polymer containing the repeating unit of the formula 1 to 3, there is no risk of polymer degradation reaction occurs during the firing process or storage, the liquid crystal showing a high imide conversion while showing excellent coating properties It was confirmed that the alignment agent can be provided and the invention was completed. Specifically, the polymer according to one embodiment includes the repeating unit of Formula 1 to 3 above. In the repeating units of Chemical Formulas 1 to 3, X ¹ to X ³ may be various tetravalent organic groups as described above, and Y ¹ to Y ³ may be various divalent organic groups as described above.

For example, each of X ¹ to X ³ may independently be a tetravalent organic group described in Formula 5 below.

[Formula 5]

In Chemical Formula 5,

R ⁵ to R ⁸ are each independently hydrogen or an alkyl group having 1 to 6 carbon atoms and L ² is a single bond, -0-, -CO-, -S-, -SO-, -S0 _2- , -C ⁹ R ¹⁰ -, -C0NH-, phenylene and any one selected from the group consisting of I,

In the above, R ⁹ and R ¹⁰ are each independently hydrogen, an alkyl group having 1 to 10 carbon atoms, or a fluoroalkyl group.

In particular, at least some of the X ¹ to X ³ may be a tetravalent organic group represented by the following Chemical Formula 5-1 in Chemical Formula 5.

[Formula 5-1]

In Formula 5-1, the definition of R ⁵ to R ⁸ is the same as the definition of Formula 5. As described above, the polymer in which at least a part of X ¹ to X ³ is a tetravalent organic group represented by Chemical Formula 5-1 may be easily decomposed by light irradiation to easily implement excellent liquid crystal alignment. On the other hand, Y ¹ to Υ ³ may be defined as a divalent organic group represented by the formula (4) can provide a polymer for a liquid crystal aligning agent of various structures capable of expressing the above-described effect.

In the general formula 4 R ³ and carbon is not substituted with R ⁴ has a hydrogen bond is, ρ or q is 2 when a plurality of R is an integer between ³ to 4, or R ⁴ may be the same or different substituents each other. In Formula 4, m is an integer of 0 to 3 may be an integer of 0 or 1.

The repeating unit represented by Chemical Formula 1 may be included in an amount of 1 to 30 mol% based on the total repeating units represented by Chemical Formulas 1 to 3. If the content of the repeating unit represented by the formula (1) exceeds the above range may indicate a problem that the orientation characteristics and orientation stability is lowered.

In addition, the repeating unit represented by the formula (1) is 5 to 30 mol ¾>, 5 to 29 mol%, 5 to 28 mol%, 8 to 29 mol% or 9 with respect to the total repeating units represented by the formula (1 to 3) To 28 mol%.

If the repeating unit represented by Formula 1 is included in less than the content range, the storage stability of the liquid crystal aligning agent may be lowered, and the electrical properties measured by the voltage integrity retention may be lowered. May result. Accordingly, by including the repeating unit represented by the formula (1) in the above-described content range can provide a polymer for a liquid crystal aligning agent excellent in all storage stability, electrical properties, orientation characteristics and orientation stability.

The repeating units represented by Formulas 2 and 3 may be included in an appropriate amount according to the desired properties.

Specifically, the repeating unit represented by Chemical Formula 2 is 10 to 70 mol%, 20 to 70 mol%, 25 to 70 mol%, 10 to 65 mol¾, 20 with respect to the total repeating units represented by Chemical Formulas 1 to 3. To 65 mol% or 30 to 65 mol¾. It is possible to provide a polymer for a liquid crystal aligning agent that exhibits proper solubility within these ranges and is excellent in process characteristics and can realize a high imidation ratio.

And, the repeating unit represented by the formula (3) is 1 to 60 mol%, 10 to 60 mol%, 15 with respect to the total repeating units represented by the formula (1) to To 60 mol% ᅳ 1 to 55 mol%, 10 to 55 mol% or 15 to 55 mol%. It is possible to provide a polymer for a liquid crystal aligning agent that exhibits excellent coating properties within such a range and excellent in process characteristics and can realize a high imidation ratio.

Such a polymer may be used as a liquid crystal aligning agent to provide a liquid crystal alignment layer that realizes excellent stability and reliability.

On the other hand, according to another embodiment of the invention, a method for producing the polymer is provided. Specifically, the polymer is prepared by reacting the tetracarboxylic acid black silver anhydride thereof with an alcohol to form an ester of the formula (7); Reacting with an ester of Formula 7 and an amine of Formula 8 to prepare an amic acid ester of Formula 9; Reducing the amic acid ester of Formula 9 to obtain a diamine of Formula 10; Reacting the diamine of Formula 10 with tetracarboxylic acid or anhydride thereof to prepare a polymer consisting of amic acid and amic acid ester; And it can be prepared through the step of imidizing the polymer consisting of the amic acid and amic acid ester.

[Formula 8]

Y ^J -NO

I ^■ [Formula 9]

In Chemical Formula 6 to 10

X ¹ is a tetravalent organic group derived from a hydrocarbon having 4 to 20 carbon atoms, or black is substituted with one or more halogens of one or more of the tetravalent organic groups, or one or more -CH ₂ -valent oxygen or sulfur atoms are not directly connected. A tetravalent organic group substituted with -0-, -CO-, -S-, -SO-, -S0 ₂ -or -C0NH-,

γ ¹ are each independently a divalent organic group represented by Formula 4,

In Chemical Formula 4,

R ³ and R ⁴ are each independently halogen, cyano group, alkyl group of 1 to 10 carbon atoms, alkenyl group of 2 to 10 carbon atoms, alkoxy group of 1 to 10 carbon atoms, fluoroalkyl group of 1 to 10 carbon atoms, or 1 to 10 carbon atoms Is a fluoroalkoxy group, p and q are each independently an integer between 0 and 4,

L ¹ is a single bond, -0-, -CO-, -S-, -S0 _2- , -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -C0 H-, -C00-, -(C¾) _z- , -0 (CH ₂ ) _z 0-, -0 (CH ₂ ) _z- , -0CH ₂ -C (CH ₃ ) ₂ -CH ₂ 0- or — C00- (CH ₂ ) _z -0C0-,

Z is an integer between 1 and 10, m is an integer between 0 and 3.

When the above-described polymer is prepared according to the preparation method of another embodiment, the content of the repeating units of Chemical Formulas 1 to 3 may be easily adjusted. Specifically, in the preparing of the ester of Chemical Formula 7, the tetracarboxylic acid black of Chemical Formula 6 may provide an ester of Chemical Formula 7 through an esterification reaction with an anhydride thereof. X ¹ in Chemical Formula 6 may be a tetravalent organic group described in Chemical Formula 5 as described above. As the alcohol, an alcohol including an alkyl group having 1 to 10 carbon atoms may be used. For example, methanol, ethanol, propanol butanol, pentanol, nucleic acidol, or the like may be used. The esterification reaction conditions are not particularly limited and may be appropriately adjusted with reference to esterification reaction conditions known in the art. The ester of Formula 7 thus prepared may react with the amine of Formula 8 to provide an amic acid ester of Formula 9. In this case, Y ¹ of Formula 8 may be various divalent organic groups represented by Formula 4, and more specifically, may be a divalent organic group listed in the description of the polymer of one embodiment. The conditions for preparing the amic acid ester are not particularly limited, and may be appropriately adjusted with reference to known amic acid production conditions. If necessary, in order to prepare the amic acid ester of the formula (9) in a higher yield, the hydroxyl group of the ester of the formula (7) may be substituted with a leaving group (leave group) easy to detach.

When the amic acid ester of Formula 9 is prepared by the step, it may be reduced to provide a diamine of Formula 10. The reduction conditions are not particularly limited, and by way of non-limiting example, the amic acid ester of Formula 9 may be reduced under a hydrogen atmosphere under a Pd-C catalyst.

The diamine of Formula 10 prepared through the above steps may be reacted with tetracarboxylic acid or anhydride thereof, which is commonly used to prepare polyamic acid, to prepare a polymer consisting of amic acid and amic acid ester. The reaction conditions may be appropriately adjusted with reference to the preparation conditions of the polyamic acid known in the art. And the polymer which has the repeating unit of Formula 1-3 which imidates the polymer which consists of the obtained amic acid and amic acid ester is mentioned above, It can manufacture.

On the other hand, according to another embodiment of the invention, there is provided a liquid crystal aligning agent comprising the polymer.

Because the liquid crystal aligning agent includes the polymer described above, the liquid crystal aligning agent effectively suppresses deterioration in stability and reliability due to polymer degradation reaction during the firing process and storage, and exhibits excellent coating properties and at the same time excellent imide conversion rate.

Such liquid crystal aligning agent may be provided through various methods known in the art to which the present invention pertains, except for including the polymer described above. As a non-limiting example, the above-described polymer may be dissolved or dispersed in an organic solvent to provide a liquid crystal aligning agent.

Examples of the organic solvent is Ν, Ν- dimethylformamide, Ν, Ν- dimethylacetamide eu Ν- methyl-pyrrolidone to the blood, Ν_ methyl caprolactam, ₂ _ avoid pyrrolidone, _Ν _ _{ethylpiperidine-2} Lidon, Ν-vinylpyridone, dimethyl sulfoxide, tetramethylurea, pyridine, dimethyl sulfone, nuxamethyl sulfoxide, butyrolactone, 3-methoxy-N, Ν- dimethylpropanamide, 3-ethoxy-Ν , Ν-dimethylpropanamide, 3-butoxy-Ν, Ν-dimethylpropanamide, 1, 3-dimethyl-imidazolidinone, ethyl amyl ketone methylnonyl ketone methyl ethyl ketone, methyl isoamyl ketone, methyl isopropyl Ketones, cyclonucleanone, ethylene carbonate, propylene carbonate, diglyme, and 4-hydroxy-4-methyl-2-pentanone. These may be used alone or in combination.

In addition, the liquid crystal aligning agent may further include other components in addition to the polymer and the organic solvent. As a non-limiting example, when a liquid crystal aligning agent is applied, it improves the uniformity and surface smoothness of a film thickness, or improves the adhesiveness of a liquid crystal aligning film and a board | substrate, or changes the dielectric constant or electroconductivity of a black liquid crystal aligning film, Alternatively, an additive that may increase the compactness of the liquid crystal alignment layer may be further included. Such additives may be exemplified by various solvents, surfactants, silane compounds, dielectrics or crosslinkable compounds.

On the other hand, according to another embodiment of the invention, a liquid crystal aligning film including the liquid crystal aligning agent described above is provided. In the above, that the liquid crystal aligning film includes the liquid crystal aligning agent means that both the liquid crystal aligning film includes the liquid crystal aligning agent itself or the liquid crystal aligning film includes a product obtained through chemical reaction of the liquid crystal aligning agent.

The liquid crystal alignment layer may be formed through various methods known in the art to which the present invention belongs, except that the liquid crystal alignment agent described above is used. As a non-limiting example, the liquid crystal alignment layer may be formed by applying and baking the above-described liquid crystal aligning agent on a substrate and then irradiating light. At this time, the firing and the light irradiation may proceed simultaneously, the light irradiation may be omitted.

Specifically, the above-mentioned liquid crystal aligning agent is apply | coated to the board | substrate which is going to form a liquid crystal aligning film. As the substrate, all the various substrates used in the art to which the present invention belongs may be used, and as the coating method, all the various methods known in the art to which the present invention belongs may be employed. As a non-limiting example, the liquid crystal aligning agent may be applied by a method such as screen printing, offset printing, pletoso printing, inkjet, or the like.

Thereafter, the previously prepared coating film is fired. The firing may be carried out at about 50 to 300 ^° C by heating means such as a hot plate, hot air circulation furnace, infrared furnace. Through this firing process, the repeating units represented by the polymer thickeners 1 and 3 included in the liquid crystal aligning agent may be imidized. The polymer may include a repeating unit represented by Formula 2, which has already been imidated, to exhibit a significantly improved imide conversion rate compared to the conventional.

After the firing step, light may be irradiated to the previously fired film according to a desired alignment direction to impart liquid crystal alignment. More specifically, the fired film may be irradiated with ultraviolet light or visible light having a wavelength of about 150 to 450 nm, and light linearly polarized in a vertical or oblique direction.

On the other hand, according to another embodiment of the present invention, a liquid crystal display device including the liquid crystal alignment layer described above is provided.

The liquid crystal alignment layer may be introduced into the liquid crystal cell by a known method, and the liquid crystal cell may likewise be introduced into the liquid crystal display device by a known method. The liquid crystal alignment layer may be prepared from a polymer including the repeating units of Chemical Formulas 1 and 2 to implement excellent stability with excellent physical properties. have. Accordingly, a liquid crystal display device capable of exhibiting high reliability is provided.

【Effects of the Invention】

The polymer according to an embodiment of the present invention effectively suppresses polymer degradation reaction in the firing process or storage for forming the liquid crystal alignment layer, exhibits excellent coating property in coating, shows high imide conversion rate in firing process, and high stability. And liquid crystal aligning agents that exhibit excellent orientation stability and electrical properties as well as reliability.

[Specific contents to carry out invention]

Hereinafter, the operation and effects of the invention will be described in more detail with reference to specific examples. However, this is presented as an example of the invention, whereby the scope of the invention is not limited in any sense.

Synthesis Example 1 Synthesis of DA-1

Amic acid ester containing diamine DA-1 was synthesize | combined from the acid anhydride according to following formula 1 below.

25 g of pyromel l i t i c di anhydride (PMDA)

250 mL of methane was added and 1-2 drops of hydrochloric acid were added. The resulting mixture was then heated to reflux at 75 ^° C. for 5 hours. Then, in the obtained product The solvent was removed under reduced pressure, and solidified by addition of ethyl acetate (EA) and 300 mL of n-nucleic acid. The resulting solid was filtered under reduced pressure and dried under reduced pressure at 40 ^° C to obtain 32 g of Ml.

100 mL of toluene was added to 32 g of the obtained Ml, and 35 g of oxalyl chloride were added at room temperature. 2-3 drops of dimethylformamide (DMF) were added dropwise and stirred at 50 ^° C. for 16 hours. After the obtained product was cooled to room temperature, the solvent and the residual oxalyl chloride were removed under reduced pressure from the product. 300 mL of n-nucleic acid was added to the yellow solid product thus obtained, and the mixture was heated to reflux at 80 ^° C. The heated reaction solution was filtered to remove impurities insoluble in n-nucleic acid. Then, the obtained solution was slowly reacted to room temperature to filter white crystals produced. The crystal thus obtained was dried in a vacuum oven at 40 ^° C to obtain 32.6 g of M2.

29.6 g of 4-nitroaniline and 21/7 g of triethanolamine (TEA) were added to 400 mL of tetrahydrofuran (THF), and 32.6 g of M2 was added at room temperature. The mixture thus obtained was stirred at room temperature for 16 hours and then the resulting precipitate was filtered off. 400 mL of dichloromethane was added to the filtrate, washed with 0.1N aqueous hydrochloric acid solution, and then washed with saturated aqueous sodium hydrogen carbonate (NaHC0 ₃ ) solution. The washed organic solution was filtered under reduced pressure to give a solid product, which was recrystallized from dichloromethane to give 43 g of M3.

43 g of M3 was placed in a high pressure reactor and dissolved in 500 mL of THF. Subsequently, 2.2 g of Pd-C having a weight of 10 3 ¾ was added to the high pressure reaction vessel, and the resultant mixture was stirred at room temperature for 16 hours under 3 atmospheres of hydrogen gas (¾). After the reaction, Pd-C was removed using a cel ite filter, filtered, and the filtrate was concentrated under reduced pressure to obtain 37 g of amic acid ester-containing diamine DA-1. Synthesis Example 2 Synthesis of DA-2

DA-2 having the above structure was synthesized in the same manner as in Synthesis Example 1, except that cyclobutanetetracarboxylic acid dianhydride (CBDA) was used instead of PMDA.

One

Example 1: Preparation of Polymer 5 for Liquid Crystal Alignment

5.0 g of DA-1 and 2.73 g of p-phenylene diamine (PDA) were completely dissolved in 140 g of anhydrous N-methyl pyrrol i done (NMP). Then, 9.8 g of 1,3_dimethyl-cyclobutanetetracarboxylic dianhydride (1,3-dimethyl-cyclobutanetetracarboxyl ic acid di anhydride (DMCBDA)) was added to the mixture under an IC bath, and the mixture was stirred at room temperature for 16 hours. A copolymer consisting of amic acid and amic acid ester (PAE-1) was synthesized.

Acetic anhydride (acet i c anhydride) in PAE-1 solution

7.2 g and pyridine 5.6 g were added, followed by stirring at room temperature for 24 hours. And the obtained product was thrown into excess distilled water and the precipitate was produced. Subsequently, the resulting precipitate was filtered, washed twice with distilled water, and washed three times with methanol. The solid product thus obtained was dried in a reduced pressure oven at 40 ^° C. for 24 hours to obtain 9.8 g of a copolymer (PAEI-1) composed of amic acid, amic acid ester and imide. As a result of confirming the molecular weight of PAEI-1 through GPC, the number average molecular weight (Mn) was 15, 800 g / nK) l, and the weight average molecular weight (Mw) was 32, 000 g / mol.

On the other hand, the composition of PAEI-1 was quantitatively analyzed as follows.

The content of imide repeating units was analyzed by comparing the NH peaks of the IR spectra of PAE-1 and PAEI-1 using an IR spectrometer. Specifically, by normalizing the aromatic peak of 1520011 ^_1 units as a standard and integrating the area (S) of the NH peak appearing in 1540cm— ¹ by substituting the following equation 1 The imidation ratio was quantified.

[Equation 1]

% Imidization = [(S _PAE ― / S _PAE ] * 100

In Equation 1, Sp _AE is the area of N—H peak appearing in 1540cm— ^one of PAE, ¾¾ _{£ 1} is the area of NH peak appearing in 1540cm ^_1 of PAEI.

The ratio of the amic acid ester was confirmed by comparing the size of the methoxy peak of the amic acid ester appearing at 3.5 to 3.9 ppm in the -NMR spectrum of PAEI. Thus, after determining the ratio of imide ratio and amic acid ester, the composition of PAEI was analyzed using the remaining ratio as the ratio of amic acid.

As a result of analyzing the composition of PAEI-1 through the same method as described above, the ratio of amic acid was 20 mol%, the ratio of amic acid ester was 22 mol%, and the ratio of imide was 58 mol¾. Example 2: Preparation of Polymer for Liquid Crystal Alignment

PAEI-2 was prepared in the same manner as in Example 1, except that 5.0 g of DA-2, 1.84 g of PDA, 6.24 g of DMCBDA, 118 g of NMP, 5.6 g of acetic anhydride, and 4.4 g of pyridine were used. . As a result of checking the molecular weight of PAEI-2 through GPC, the number average molecular weight (Mn) was 15,500 g / nK) l, and the weight average molecular weight (Mw) was 27,000g / ii) l. And as a result of analyzing the composition of PAEI-2, the ratio of amic acid was 21 mol%, the ratio of amic acid ester was 28 mol%, and the ratio of imide was 51 mol%. Example 3: Preparation of Polymer for Liquid Crystal Alignment

Example 1 except for using DA-1 4.0g, PDA 2.81g, oxydianiline (ODA) 1.59g, DMCBDA 9.5g, NMP 16 lg, acetic anhydride 8.7g, pyridine 6.7g PAEI-3 was prepared using the same method as 1. As a result of confirming the molecular weight of PAEI-3 through GPC, the number average molecular weight (Mn) is 17,000g / mol, the weight average molecular weight (Mw)

36,000 g / mol. And, as a result of analyzing the composition of PAEI-3, the ratio of amic acid was 30 mol%, the ratio of amic acid ester was 15 mol%, and the ratio of imide was 55 mol¾. Example 4: Preparation of Polymer for Liquid Crystal Alignment

In Example 1, DA-2 2.0g, PDA 3.44g, 4,4 '-(1,3-propanediyl) dioxydianiline (4, 4'-(1, 3-propanediyl) dioxydini ine: PODA ) 2.2g, DMCBDA 7.94g, 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride (3 ᅳ 3', 4,4'-biphenyltetracarboxyl ic acid di anhydride: BPDA) 2.67g, phthalic anhydride (phthal PAEI-4 was prepared in the same manner as in Example 1, except that 0.27 g of ic anhydride), 167 g of NMP, 9.2 g of acetic anhydride, and 7.2 g of pyridine were used. As a result of confirming the molecular weight of PAEI-4 through GPC, the number average molecular weight (Mn) was 13, 500 g / irol, and the weight average molecular weight (Mw) was 28,000 g / mol. As a result of analyzing the composition of PAEI-4, the ratio of amic acid was 29 mol%, the ratio of amic acid ester was 9 mol%, and the ratio of imide was 62 mol%. Example 5: Preparation of Polymer for Liquid Crystal Alignment

PAE-3 was prepared in Example 3, followed by addition of acetic anhydride and pyridine, followed by stirring at room temperature for 6 hours, to prepare PAEI-5 using the same method as in Example 3. As a result of confirming the molecular weight of PAEI-5 through GPC, the number average molecular weight (Mn) was 17, 500 g / iM l, and the weight average molecular weight (Mw) was 38,000 g / m. And as a result of analyzing the composition of PAEI-5, the ratio of amic acid was 44 mol%, the ratio of amic acid ester was 16 mol%, and the ratio of imide was 40 mol%. Example 6: Preparation of Polymer for Liquid Crystal Alignment

PAE-3 was prepared in Example 3, followed by addition of acetic anhydride and pyridine, followed by stirring at room temperature for 3 hours, to prepare PAEI-6 using the same method as in Example 3. As a result of confirming the molecular weight of PAEI-6 through GPC, the number average molecular weight (Mn) was 17, 500 g / n) l, and the weight average molecular weight (Mw) was 38,000 g / irol. And as a result of analyzing the composition of PAEI-6, the ratio of amic acid was 52 mol%, the ratio of amic acid ester was 32 mol%, and the ratio of 16 mol imide. Example 7: Preparation of Polymer for Liquid Crystal Alignment

DA-2 0.7g, PDA 4.12g, DMCBDA 8.73g, NMP 122g in Example 1, PAEI-7 was prepared using the same method as Example 1 except for using 7.9 g of acetic anhydride and 6.¾ of pyridine. As a result of confirming the molecular weight of PAEI-7 through GPC, the number average molecular weight (Mn) was 14,000 g / ii) l, and the weight average molecular weight (Mw) was 23,000 g / mol. And as a result of analyzing the composition of PAEI-7, the ratio of amic acid was 39 mol%, the ratio of amic acid ester was 4 mol%, and the ratio of imide was 57 mol%. Comparative Example 1: Preparation of Polyamic Acid

5.0 g of PDA and 2.13 g of ODA were completely dissolved in 140 g of anhydrous NMP. Then, DMCBDA10.lg and PMDA 2.52g were added to the mixture under an ice bath, followed by stirring at room temperature for 16 hours to synthesize polyamic acid (PM-1). As a result of confirming the molecular weight of PM-1 through GPC, the number average molecular weight (Mn) was 22,000 g / mol, and the weight average molecular weight (Mw) was 41,000 g / m. Comparative Example 2: Preparation of Polyamic Acid Ester

PAE-3 was prepared in the same manner as in Example 3. However, acetic anhydride and pyridine were added to PAE-3 to prevent imidization reaction. As a result of confirming the molecular weight of PAE-3 through GPC, the number average molecular weight (Mn) was 22,000 g / m, the weight average molecular weight (Mw) was 43, 000 g / m. Comparative Example 3: Preparation of partially imidized polyamic acid

PAA-1 was prepared in the same manner as in Comparative Example 1. Then, 11.6 g of acetic anhydride and 8.9 g of pyridine were added to PM-1, followed by stirring at room temperature for 24 hours. Then, the obtained product was poured into excess distilled water to produce a precipitate. Subsequently, the resulting precipitate was filtered, washed twice with distilled water, and washed three times with methane. The solid product thus obtained was dried for 24 hours at 40 ^° C. under reduced pressure obon to obtain a copolymer (PAI-1) consisting of amic acid and imide. As a result of confirming the molecular weight of the PAI-1 through GPC, the number average molecular weight (Mn) was 17,000g / mol, the weight average molecular weight (Mw) was 36,000g / nxl. ^And: the composition ratio of amic acid analysis was 45% and has already Mall ratio of PAI-1 is de 55 mol%. Comparative Example 4: Preparation of partially imidized polyamic acid ester

PEI-1 was prepared in the same manner as in Example 1, except that 10 g of DA-1, 4.8 g of DMCBDA, 133 g of NMP, 4.3 g of acetic anhydride, and 3.4 g of pyridine were used. As a result of confirming the molecular weight of the PEI-1 through GPC, the number average molecular weight (Mn) is 20, 000 g / mol, the weight average molecular weight (Mw)

Was 41, 000 g / m. Then, as a result of analyzing the composition of PEI-1, the ratio of amic acid was 0 mol%, the ratio of amic acid ester was 47 mol%, and the ratio of imide was 53 mol ¾). Comparative Example 5: Preparation of Polymer for Liquid Crystal Alignment

PAEI-7 was prepared in the same manner as in Example 1, except that 8-1 of DA-2, 1.31 g of PDA, 6.65 g of DMCBDA, 143 g of NMP, 6.1 g of acetic anhydride, and 4.7 g of pyridine were used. As a result of confirming the molecular weight of PAEI-7 through GPC, the number average molecular weight (Mn) was 17, 000 g / n l, and the weight average molecular weight (Mw) was 29, 000 g / m. As a result of analyzing the composition of PAEI-7, the ratio of amic acid was 17 mol%, the ratio of amic acid ester was 35 mol%, and the ratio of imide was 48 mol%. Test Example: Evaluation of Characteristics of Liquid Crystal Alignment Film

(1) Preparation of liquid crystal aligning agent

Each of the polymerizers prepared according to Examples 1 to 7 and Comparative Examples 1 to 5 was dissolved in a mixed solvent having a weight ratio of P and _n -butoxyethanol at 8: 2 in a ratio of 5% by weight of solids. Then, the obtained solution was filtered under pressure with a filter having a pore size of 0.2 / poly (tetrafluoreneethylene) material to prepare a liquid crystal aligning agent.

(2) Preparation of liquid crystal cell

By using the liquid crystal aligning agent prepared above by the following method A liquid crystal cell was prepared.

Substrate with an in-plane swi tching (IPS) mode Π 60 electrode pattern with a thickness of 60rai, electrode width 3, and spacing between electrodes on a rectangular glass substrate measuring 2.5cm x 2.7cm (bottom plate) The liquid crystal aligning agent was apply | coated to the glass substrate (top plate) without and an electrode pattern using a spin coating method, respectively. Subsequently, the substrate to which the liquid crystal aligning agent was applied was placed on a hot plate ^at about 70 ^° C., dried for 3 minutes, and then calcined (cured) at about 230 ^° C. for 5 minutes to obtain a coating film having a film thickness of 0.01 kPa.

In order to orientate the coating film thus obtained, ultraviolet rays of 254 nm were irradiated with an exposure amount of U / cm ² using an exposure machine with a line polarizer attached to each of the upper and lower coating films.

Subsequently, a sealing agent impregnated with a ball spacer having a size of 3 / m was applied to the edge of the upper plate except for the liquid crystal injection hole. After the alignment films formed on the upper and lower plates face each other and are aligned so that the alignment directions are parallel to each other, the upper and lower plates are bonded to each other and the empty cell is prepared by curing the sealing agent. Then, a liquid crystal was injected into the empty cell to prepare a liquid crystal cell of IPS mode.

(1) Evaluation of coating property of liquid crystal aligning agent

The coating property of the liquid crystal aligning agent was evaluated through the state of the coating film obtained by coating the liquid crystal aligning agent. More specifically, as described above, after the liquid crystal aligning agent of the Examples and Comparative Examples were coated on the upper and lower plates by spin coating, the upper and lower plates coated with the liquid crystal aligning agent were placed on a hot plate of about 70 ^° C. for 3 minutes. Dried. And the surface of the obtained coating film was observed with the naked eye and the microscope, and the coating spot, the pinhole, and the roughness of the coating film surface were confirmed. As a result of the check, if there is no abnormality, 'good' is indicated in Table 1 as 'bad'.

(2) Evaluation of imidation ratio of liquid crystal aligning film

After coating in the manufacturing process of the liquid crystal cell obtained by baking (curing) for 30 minutes in an oven at 230 ^° C and IR spectrum of the coating film dried on a hot plate ^at 70 ^° C for 3 minutes The IR spectrum of the coating film was obtained. In addition, after comparing the area (S) of the NH peak appearing in the 1540cm- ¹ band in the IR spectrum, the ratio of reduction after firing at 23 CTC was defined as the imidization ratio, and the ratio was calculated and shown in Table 1 below. (3) evaluation of liquid crystal alignment characteristics

The polarizing plates were attached to the upper and lower plates of the liquid crystal cell manufactured by the above method so as to be perpendicular to each other. And the liquid crystal cell with a polarizing plate was put on the backlight of brightness cd / m <^2> , and light leakage was observed visually. Observation results 하였다 When the light is not passed through the liquid crystal cell and is observed dark, 'good', and when light leakage such as liquid crystal flow marks or bright spots is observed, it is indicated in Table 1 as 'bad'.

(4) liquid crystal orientation stability evaluation

The liquid-crystal orientation stability was evaluated using the liquid crystal cell with a polarizing plate manufactured for said (3) liquid-crystal orientation characteristic evaluation.

Specifically, the liquid crystal cell with the polarizing plate was attached on the backlight of 7,000 cd / m ² , and the luminance of the black state was measured using the PR-880 equipment, which is a luminance brightness measuring equipment. Then, the liquid crystal cell was driven for 24 hours at 5V at room temperature. Thereafter, the luminance of the black state was measured in the same manner as described above in the state in which the voltage of the liquid crystal cell was turned off.

The difference between the initial luminance L0 measured before driving the liquid crystal cell and the later luminance L1 measured after driving was divided by the initial luminance L0 value and multiplied by 100 to calculate the luminance variation rate. The calculated luminance fluctuation rate is closer to, which means that the orientation stability is excellent. If the luminance fluctuation rate is less than 10%, it is shown in Table 1 as 'good', 10% or more and less than 20%, 'normal', and 20% or more as 'bad'.

(5) Evaluation of Voltage Maintenance Integrity (VHR) of Liquid Crystal Cell

The voltage retention preservation ratio (VHR), which is an electrical characteristic of the liquid crystal cell manufactured by the above method, was measured using a T0Y0 6254 device. Voltage retention integrity was measured at 60Hz, 60 ^° C under dark conditions. 100% is the ideal value, and the measurement result is 'excellent' if more than 90%, 'normal', 80% if less than 90% or more If less, it is shown in Table 1 as 'defect'.

Table 11

Claims

[Claim]

[Claim 1]

A repeating unit represented by the following formula (1), represented by the following formula (2)

A unit and a repeating unit represented by the following Chemical Formula 3,

Polymer for liquid crystal aligning agent containing 1-30 mol% of repeating units represented by following formula (1) with respect to all the repeating units represented by following formula (1)-(3):

[

In Chemical Formulas 1 to 3,

X ¹ to X ³ are each independently a tetravalent organic group derived from a hydrocarbon having 4 to 20 carbon atoms, or black is one or more H of the tetravalent organic group is substituted with halogen, or one or more -c¾-valent oxygen or sulfur Is a tetravalent organic group substituted with —0-, -co-, —S-, -so-, -so ₂ -or -CO

Y ¹ to Y ³ are each independently a divalent organic group represented by the following formula (4),

In Chemical Formula 4

L ¹ is a single bond, -0-, -CO-, -S-, -S0 _2- , -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , -C0NH-, -C00-,- (CH ₂ ) _2- , -0 (CH ₂ ) _z 0-, -0 (CH ₂ ) _z- , -0CH ₂ -C (CH ₃ ) ₂ -CH ₂ 0- or -C00- (CH ₂ ) _z -οω-,

Z is an integer between 1 and 10, and m is an integer between 0 and 3.

[Claim 2]

The polymer for liquid crystal aligning agent according to claim 1, wherein X ¹ to X ³ are each independently a tetravalent organic group represented by the following general formula (5):

[Formula 5]

In Chemical Formula 5,

R ⁵ to R ⁸ are each independently hydrogen or a malky group having 1 to 6 carbon atoms

L ² is selected from the group consisting of a single bond, -0-, -CO-, -S-, -SO-, -S0 _2- , -CR ⁹ R ^10- , -CO 丽-, phenylene or a combination thereof Which one,

In the above, R ⁹ and R ¹⁰ are each independently hydrogen, of 1 to 10 carbon atoms An alkyl group or a fluoroalkyl group.

[Claim 3]

The polymer for a liquid crystal aligning agent of claim 1, wherein at least some of X ¹ to X ³ are tetravalent organic groups represented by the following Chemical Formula 5-1:

In Chemical Formula 5-1,

R ⁵ to R ⁸ are each independently hydrogen or an alkyl group having 1 to 6 carbon atoms.

[Claim 4]

The polymer for a liquid crystal aligning agent according to claim 1, comprising 5 to 30 mol% of the repeating units represented by the formula (1) to all the repeating units represented by the formulas (1) to (3).

[Claim 5]

The polymer for a liquid crystal aligning agent according to claim 1, comprising 10 to 70 mole% of the repeating unit represented by the formula (2) to all the repeating units represented by the formula (1) to (3).

[Claim 6]

The polymer for a liquid crystal aligning agent according to claim 1, comprising 1 to 60 mol% of repeating units represented by Formula 3 to all the repeating units represented by Formulas 1 to 3.

[Claim 7]

Tetracarboxylic acid or anhydride thereof of Formula 6 Preparing an ester of Formula 7 by reacting with esterification;

Reacting with the ester of Formula 7 and the amine of Formula 8 to prepare an amic acid ester of Formula 9;

Reducing the amic acid ester of Formula 9 to obtain a diamine of Formula 10;

Reacting the diamine of Formula 10 with tetracarboxylic acid or anhydride thereof to prepare a polymer consisting of amic acid and amic acid ester; And a step of imidizing a polymer consisting of the amic acid and the amic acid ester:

[Formula 8]

Y'-NO

I ·

[Formula 10]

In Chemical Formula 6 10,

X ¹ is a tetravalent organic group derived from a hydrocarbon of 4 to 20 carbon atoms, at least one H of the tetravalent organic groups is substituted with halogen, or at least one -c¾- is not directly connected to oxygen or sulfur atoms- A tetravalent organic group substituted with 0-, -co-, -S-, -SO-, -S0 ₂ -or -C0NH-,

γ ¹ are each independently a divalent organic group represented by Formula 4,

In Chemical Formula 4,

L ¹ is a single bond, -0-, -CO-, -S-, -S0 _2- , -C (CH ₃ ) _2- , -C (CF ₃ ) _2- , —C0NH-, -C00-,- (C¾) _z- ， — 0 (CH ₂ ) _z 0—, -0 (CH ₂ ) _z- , -0GH ₂ -C (CH ₃ ) ₂ -CH ₂ 0- or -C00— (CH ₂ ) _Z- 0C0-,

Z is an integer between 1 and 10,

m is an integer between 0 and 3.

[Claim 8]

A liquid crystal aligning agent comprising the polymer according to any one of claims 1 to 6. [Claim 9]

The liquid crystal aligning film containing the liquid crystal aligning agent of Claim 8. [Claim 10]

A liquid crystal display device comprising the liquid crystal alignment film of claim 9.