KR101451162B1 - Chalcone photoalignment material with maleimide derivative as main chain and the synthetic method thereof - Google Patents

Abstract

The present invention relates to a chalcone photoalignment material with a maleimide based main chain and a manufacturing method thereof and, more specifically, to a chalcone photoalignment material which has excellent solubility, photoalignment stability and thermal stability by the formation of a chemical structure, wherein a chalcone based photoreactive group is connected to a main chain of a maleimide derivative. A manufacturing method for a polymaleimide based compound including a chalcone group comprises: i) a step of synthesizing polymaleimide derivatives through the reaction of primary amines and maleic anhydride derivatives; ii) a step of synthesizing chalcone derivatives; and iii) a step of esterifying the polymaleimide derivatives of step i) and the chalcone derivatives of step ii).

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a chalcone-based photoalignment material having a maleimide-based main chain and a manufacturing method thereof,

The present invention relates to a photochromic alignment material having a maleimide-based main chain and a method for producing the same, wherein a chemical structure in which a polycondensation reaction group is linked to a maleimide derivative main chain is formed, To an excellent photo-alignment material.

Recently, a demand for a display device capable of realizing a 3D image for expressing a more realistic image is increasing, and related technologies are being actively developed. As one of the core technologies of 3D display, the film type pattern retarder (FPR), which is an optical material of polarizing type 3D display, is attracting much attention in terms of enlargement and cost reduction. The patterned retarder serves to make different phase values for the left eye image and the right eye image out of the 2D images coming out of the liquid crystal display device, and it also functions as a spectacle retarder for selectively transmitting an image through the patterned retarder So that 3D images can be viewed.

In the production of the liquid crystal pattern retarder, multidomain formation is required, and for this purpose, the photo-alignment method using the photo-alignment material is effective. The photopolymerization reaction is a mechanism of forming a photopolymerizable liquid crystal alignment layer in which a photoreactive material bonded to a photoreactive polymer is caused to undergo a photoreaction by a linearly polarized UV so that the liquid crystal is aligned. For this purpose, when irradiating linearly polarized ultraviolet light, the photoreactive material should be arranged in a certain direction and angle according to the polarization direction, and the liquid crystal alignment with the reactive liquid crystal should be well matched with the reactive liquid crystal . In particular, the photo alignment material forming the photo alignment layer should have good physical properties such as printability, orientation stability, and thermal stability.

On the other hand, as a photo alignment layer material, a poly-polycondensation polymer such as polyvinyl chalcone or polyvinylmethoxylsaccharone is known. This is because the double bond of the chalcone by the irradiated ultraviolet light causes the [2 + 2] cyclization addition reaction to form cyclobutane Thereby forming anisotropy and aligning the liquid crystal molecules in one direction to induce alignment of the liquid crystal. In addition, a polymer having a side chain containing a photosensitive group in its main chain such as acrylate and methacrylate, and an alignment film containing the polymer are known.

However, the above-mentioned photo alignment film materials have a disadvantage in that the thermal stability of the polymer main chain is deteriorated and the orientation stability or thermal stability of the orientation film is poor, or the liquid crystal orientation property is not sufficiently manifested. When introducing a low molecular weight substance, it is required to cross-link the polymer before irradiation to obtain an isomerized or dimerized molecule, or to require a relatively long irradiation time, and as a result, a photo alignment material having a short irradiation time and excellent processability is required . In particular, mass production requires easy synthesis of materials, uniform light distribution, and satisfactory properties for optical alignment stability.

On the other hand, Korean Patent Publication No. 10-2012-0014543 discloses a maleimide compound having a photoreactive group. However, it may be in the form of a maleimide compound in the form of a monomer containing a photoreactive group, or a method in which a maleimide in the form of a monomer containing a photoreactive group is subjected to a radical addition polymerization reaction using AIBN or the like, . There is still a problem that the photo-dispersing agent produced in this form is not mass-producible enough and the electro-optical properties are not sufficient.

In order to solve the above problems, the present invention aims to improve the physical properties such as solubility, stability of liquid crystal alignment, thermal stability, and mechanical properties by forming a chemical structure in which an imide group, a polycondensation reaction group and the like are linearly connected .

In order to improve the productivity, a new method of polymerization is employed to provide a poly (maleimide) compound including a polycondensate and the like which is more convenient and yielded.

For this purpose, the present invention relates to a process for preparing a maleimide derivative, comprising the steps of: i) synthesizing a maleimide derivative through reaction of a maleic anhydride derivative with a primary amine; Ii) synthesizing a substance having a photoreactive group; Iii) subjecting the polyimide derivative of i) to a esterification reaction with a substance having a photoreactive group of the step ii).

The poly (maleimide) in the step (i) may be a copolymerized form by using a copolymerized form of the different maleic anhydride derivatives.

The material having the photoreactive group in the step ii) is preferably a chalcone-based derivative.

In the step (i), a polymaleimide derivative is synthesized by reacting a primary amine represented by the general formula (2) with a material having a repeating unit represented by the general formula (1).

≪ Formula 1 >

Wherein k is from 0 to 10, 1 is from 1 to 100,000, m is from 1 to 100,000, n is from 1 to 100,000, Y is oxygen or an alkylene of 2 to 14 carbon atoms, R ₁ and R ₂ A substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alkoxyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 1 to 10 carbon atoms, an OH And COOH)

(2)

NH ₂ - (CH ₂ ) _n -OH

(Where n is 1 to 20)

In Formula 1, R ₁ and R ₂ Preferably being selected from the group consisting of each _{H, CH 3, CH 2 CH} 3, OCH 3, OCH 2 CH 3, COOCH 3, COOCH 2 CH 3, X (Halogen group), OH , and COOH.

In the step (ii), a Schalkone derivative of the formula (6) is synthesized through Clagen reaction of the compound represented by the formula (3) and the compound represented by the formula (4).

(3)

≪ Formula 4 >

(Wherein X is hydrogen, a halogen atom, or a group selected from the group represented by the following formula (5)

≪ Formula 5 >

Wherein X ₁ , X ₂ , X ₃ , X ₄ and X ₅ each represent a hydrogen atom, a halogen group element, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted group having 4 to 8 carbon atoms Substituted or unsubstituted C1-C20 alkoxy, substituted or unsubstituted C1-C20 alkoxyl, substituted or unsubstituted C6-C40 aryl,

(6)

(Wherein X is as defined in Chemical Formula 4)

The present invention provides a polymaleimide-based compound prepared by the above-mentioned method, and a photo-alignment composition can be prepared using such a material, and it can be contained in an amount of 1 to 15% by weight. The solvent of the photo-alignment composition is preferably 1: 9 to 9: 1 MEK: Toluene, and most preferably 3: 7. The composition may include additives such as a surfactant, a crosslinking agent, and a photoactive agent.

The present invention provides an orientation film comprising the above-mentioned poly (maleimide) compound and an orientation film. Such an orientation film and an orientation film can be used not only as a phase retardation film for 3D FPR but also as an alignment material for horizontal, inclined, vertical liquid crystal mode, and a photo-alignment material for 3D rendicule lens.

The present invention is advantageous in that it has excellent physical properties due to the rigid chain structure of the maleimide group and has unique electrical characteristics. The stability of liquid crystal alignment, thermal stability, mechanical properties and the like are remarkably improved by taking the form of the linear alignment of the alignment materials.

Further, by introducing an ether group or the like into the main chain, orientation and solubility can be further improved.

Although it is not easy to achieve the mass productivity in the conventional method of polymerizing the monomer form, according to the production method of the present invention, it is possible to polymerize more easily and stably, Can be synthesized.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing a schematic chemical structure of a Shallon-based poly (maleimide) photo-alignment material of the present invention. FIG.
FIG. 2 shows a process for synthesizing a poly (maleimide) derivative by reacting a maleic anhydride derivative with a primary amine according to an embodiment of the present invention,
FIG. 3 shows a process of synthesizing a chalcone derivative according to an embodiment of the present invention,
FIG. 4 shows a process for synthesizing a polymaleimide-based compound containing a chalcone group of the present invention by esterifying a polyalmaleimide derivative and a chalcone derivative according to an embodiment of the present invention.
Figure 5 is a graphical representation of a compound according to one embodiment of the present invention.
Figure 6 shows the FT-IR spectral spectrum of Example 3,
7 shows the 1 H-NMR spectroscopic spectrum of Example 3. Fig.
FIG. 8 shows the result of measurement of the phase difference change at 70 degrees in Test Example 2 for 72 hours.

The present invention relates to a maleimide compound of the type shown in Figure 1 and also relates to a process for its preparation. In FIG. 1, a circle indicates a maleimide derivative, and various types of functional groups are possible. In Fig. 1, A represents a functional group including a photoreactive group. In Fig. 1, S represents a spacer connecting the maleimide moiety and the photoreactive moiety.

S is a spacer which is a simple bond (linear or branched alkyl) having 1 to 20 carbon atoms, a substituted or unsubstituted alkylene having 1 to 20 carbon atoms, a substituted or unsubstituted alkenylene having 2 to 20 carbon atoms, A substituted or unsubstituted arylene group having 6 to 40 carbon atoms, a substituted or unsubstituted arylene group having 7 to 15 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 15 carbon atoms, And substituted or unsubstituted alkynylene of 2 to 20 carbon atoms. More preferably a straight-chain alkyl having 2 to 8 carbon atoms, and is most easily reacted. In the present invention, a synthesis is carried out using linear primary amines. However, it should be considered within the scope of the present invention if a variety of substituted or unsubstituted primary amines can be used in the view of those skilled in the art. For example, if there is reactivity and ease of synthesis, the following may be used in the form of a spacer.

A is a functional group containing a photoreactive group, and may include a cinnamate-based, coumarin-based, chalcon-based or azo-based photoreactive group, preferably a chalcone series. In addition, various side chains or end groups can be bonded to the polycondensation functional group, and the side chains and the end groups can form a rod-like structure, so that a chemical structure having strong interaction with the reactive liquid crystals can be formed.

For ease of reference and reaction and synthesis from the standpoint of those skilled in the art, the following may be more variously included.

On the other hand, in the case of a conventional maleimide-based compound having a photoreactive group, a method of producing a maleimide monomer containing a photoreactive group by radical polymerization using AIBN or the like is used . In this case, it is difficult to make the maleimide derivative portion more diverse, and therefore, it is difficult to improve the properties of the light control agent material. In addition, since the maleimide monomers containing a photoreactive group are prepared in the form of being polymerized, the production process becomes complicated, and in practice, polymerization is difficult, and the yield is low and there is a problem in mass productivity.

In the present invention, a polymerized maleic anhydride derivative and a primary amine are reacted to improve the above point, and a poly (maleimide derivative) is synthesized first. In one embodiment, the following reaction procedure is illustrated.

Wherein R < ₁ > and R < _{2 &} Is _{H, CH 3, CH 2 CH} 3, OCH 3, OCH 2 CH 3, COOCH 3, COOCH 2 CH 3, X (Halogen group), preferably being selected from the group consisting of OH and COOH, m are each 2 to 5,000, and n of the primary amine is preferably 1 to 10)

The form of the maleic anhydride derivative can be changed in various ways.

≪ Formula 1 >

Wherein k is from 0 to 10, 1 is from 1 to 100,000, m is from 1 to 100,000, n is from 1 to 100,000, Y is oxygen or an alkylene of 2 to 14 carbon atoms, R ₁ and R ₂ A substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alkoxyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 1 to 10 carbon atoms, an OH And COOH)

In the above formula (1), the form of the following formula (5) will be a relatively highly usable form, and may be preferable considering ease of synthesis, reactivity and yield.

≪ Formula 5 >

(Wherein, m is from 2 to 10,000, n is 1 to 5, Y is oxygen or alkylene having 2 to 14, R ₁ and R ₂ A substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alkoxyl group having 1 to 10 carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 1 to 10 carbon atoms, an OH And COOH, and S is a spacer selected from the group consisting of a simple bond, a substituted or unsubstituted alkylene having 1 to 20 carbon atoms, a substituted or unsubstituted alkenylene having 2 to 20 carbon atoms, a substituted or unsubstituted carbon number Substituted or unsubstituted arylene having 6 to 40 carbon atoms, substituted or unsubstituted arylene having 7 to 15 carbon atoms, substituted or unsubstituted arylene having 7 to 15 carbon atoms, and Substituted or unsubstituted C2-C20 alkynylene, and A is a photoreactive functional group containing a chalcone group)

In the case of the above-mentioned reaction, the polymerization is carried out without the photoreactive group, so that it can proceed more easily.

Next, the photoreactive group is synthesized separately. There are a number of known techniques for the synthesis of photoreactive groups. In the present invention, it is preferable to select a Shalcone series in a form having optimized optical alignment characteristics. In one embodiment, the following reaction procedure is illustrated.

(Wherein X represents a halogen atom, a substituted or unsubstituted alkyl of 0 to 20 carbon atoms, a substituted or unsubstituted cyclic alkyl of 4 to 8 carbon atoms, a substituted or unsubstituted alkoxy of 1 to 20 carbon atoms, A substituted or unsubstituted aryl group having 6 to 40 carbon atoms)

The Clagen reaction is a reaction well known to those skilled in the art, in which the carboxylic acid ester forms a two-molecule condensed keto acid ester in the presence of a base such as sodium alkoxide, sodium amide and the like.

Next, a photoreactive group is reacted with a poly (maleimide) derivative to synthesize a poly (maleimide) compound containing a photoreactive group. As examples of the photoreactive group, the above-mentioned chalcone derivative is preferable. In one embodiment, the following reaction process is illustrated.

As described above, the method of synthesizing the poly (maleimide derivative) and the chalcone derivative through an esterification process is easier and more mass-producible. It is much easier to synthesize conventional monomers and then radical-polymerize them.

The present invention can be produced in the form of a derivative having photo-alignment properties with better physical properties by the above-described production method. FIG. 5 graphically shows a form in which 10 units are repeated.

The maleimide main chain of the form provided by the present invention has a different form from the conventional one. The reason for this is that when synthesized by a conventional method, it is not easy to synthesize a main chain having a side chain or the like as in the present invention, and the solubility and other properties The properties can be changed. Some prior art documents that are presented as partially hypothetically possible can not implement the main chain form presented in the present invention.

A photo alignment layer composition can be prepared using the photo alignment material according to the manufacturing method of the present invention, and the composition can be contained in an amount of 1 to 15% by weight. When the amount is too small, the photo-alignment property can not be satisfied, and it is not preferable to include too much in consideration of other additives. The solvent of the photo-alignment composition is preferably 1: 9 to 9: 1 MEK: Toluene, and most preferably 3: 7. A method of improving the physical properties by using a solvent having a high solubility of a photo-aligning substance together with a solvent having no solubility can be considered. The present combination shows good results, and as a solvent of a substance proposed in the present invention, I think that the study should go a bit further. Such compositions may contain additives such as surfactants, crosslinking agents, and photoactive agents. Various modifications may be made by those skilled in the art without departing from the spirit and scope of the invention.

The present invention provides an orientation film comprising the above-mentioned poly (maleimide) compound and an orientation film. Such an orientation film and orientation film may be used not only as a phase retardation film for 3D FPR but also as an orientation material for horizontal, oblique, vertical liquid crystal mode, and a photo-alignment material for 3D rendiculer lens.

Hereinafter, preferred embodiments of the present invention will be described in order to explain the present invention in more detail. The following Examples and Experiments are merely an embodiment of the present invention, and the film of the present invention and the production method thereof and their effects are not limited by the method described below, It is clear to those who have knowledge.

Example 1 Synthesis of Polymaleimide Derivatives

Synthesis was carried out using a 3-necked round bottom flask and a dean-stark condenser with poly (isobutylene-alt-maleic anhydride) (0.01 mol) and spacer 6-amino-1-hexanol (0.011 mol) As a solvent, NMP and toluene forming an azeotropic mixture were reacted at room temperature for 24 hours and at 200 ° C. for 12 hours. The compound was precipitated in water, filtered and vacuum dried for 24 hours or more to obtain a compound. The synthetic poly-maleimide derivatives is 88% yield as a white solid, 57 ℃ T _g and T _m 117 ° C.

Example 2 Synthesis of Shalcone Derivative

Synthesis of chalcone derivatives was carried out by reacting 4-fluoro-acetophenone (0.001 mol) with 4-formylbenzoic acid (0.0011 mol) at 120 ° C. for 3 hours in 100 mL of acetic acid solvent using sulfuric acid catalyst. The solution was precipitated in water, neutralized with 2% aqueous sodium chloride solution and then filtered and washed with hot water. After filtration, it was dried in a vacuum oven for over 24 hours. The reaction yield was 93% and melting point was 263 ℃.

≪ Example 3 > Synthesis of polymaleimide compound containing chalcone group

(0.010 mol) of the compound of Example 1 (0.012 mol) and 0.012 mol of the compound of Example 2 were dissolved in a THF solvent (200 mL), and 0.015 mol of 4-dimethylaminopyridine (DMAP) and N, N '-dicyclohexylcarbodiimide (DCC) for 48 hours at room temperature. The reaction progress was confirmed by TLC monitering and filtration was performed to remove urea after termination. The remaining filtrate was purified through precipitation in ethanol and dried in a vacuum oven at 80 ° C for 24 hours to synthesize a polymaleimide compound containing a chalcone group. The yield of the compound was 88% and the T _m was 122 캜.

 The overall reaction process is as follows.

The result of measurement of the maleimide-based photoadhesive material including the above-mentioned chalcone group synthesized by FT-IR spectroscopy is shown in FIG.

Next, the results of measurement using H-NMR spectroscopy are shown in FIG.

As a result, it can be seen that the maleimide-based photo-alignment material including the chalcone group of the present invention was clearly synthesized.

≪ Test Example 1 > Measurement of solubility

The solubility of the optically oriented compound of the present invention in various solvents was measured in order to demonstrate the effect of preventing the damage by the solvent in the 3D FPR. The results are as follows.

No.
Solvent (1 mL) Solubility One Acetone ++ 2 Ethyl Acetate (EA) ++ 3 Tetrahydrofuran (THF) ++ 4 Choroform ++ 5 Methylene Chloride ++ 6 Methy Ethyl Ketone (MEK) ++ 7 Propylene Glycol Monomethyl Ether Acetate
(PGMEA) ++

* ++: Good Soluble, +: middle soluble, -: nonsoluble

≪ Test Example 2 > Property evaluation

The photo-alignment material prepared in Example 3 was dissolved in MEK and toluene (3: 7) at a concentration of 2% by weight, the solution was dropped on a TAC film and coated and dried at 100 ° C for 1 minute. The coating film was irradiated with 20 mJ / cm ² polarized UV. RM liquid crystal was coated on the formed alignment film, followed by drying at 80 ° C for 1 minute and UV curing at 1 J / cm ² to complete the retardation film. It was confirmed that a homogeneous coating film was formed on the film and the film was inserted between the polarizing plates which had orthogonal orientation.

Coating property was excellent, and orientation and thermal stability were also excellent. In addition, after forming the orientation film, it was evaluated whether or not the film was thermally stressed in the convection oven for 70 and 72 hours, and then the temperature was lowered again and the orientation was excellent even after the thermal stress. As a result, the thermal durability of the polyacrylamide-based compound including the chalcone group was excellent because the change in the retardation of the orientation film was slightly changed by about 1.2%.

Claims (12)

I) synthesizing a polymaleimide derivative through reaction of a primary amine represented by the general formula (2) by selecting a substance having a repeating unit represented by the general formula (1);
Ii) preparing a Shallon-based derivative represented by the following formula (6); And
Iii) a step of esterifying the polyalmaleimide derivative of the formula (7) and the polycondensate of the formula (6) in the step (ii).
≪ Formula 1 >

(2)
NH ₂ - (CH ₂ ) _p -OH
(6)

≪ Formula 7 >

N is 1 to 100,000, p is 1 to 20, n 'is 1 to 20, R ₁ and R ₂ are each a hydrogen atom, Are each CH ₃

delete delete delete delete The method according to claim 1,
Wherein the step (ii) is a step of synthesizing a Shalcone derivative represented by the formula (6) through a Clay reaction between the substance represented by the formula (3) and the substance represented by the formula (4).
(3)

≪ Formula 4 >

(6)

Wherein X is a halogen element. delete delete delete delete delete delete

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