KR20130132036A - Photo-initiator free polymerizable mesogens and polymerizable liquid crystal compositions containing the same - Google Patents

Abstract

The present invention relates to photo-initiator free polymerizable mesogen and a polymerizable liquid crystal composition containing the same. More specifically, the polymerizable mesogen uses furyl acrylate as a photosensitive group to be photocrosslinked without using a photo-initiator, to be polymerized at relatively low energy, to have excellent solubility with the host liquid crystal by having an asymmetric structure, and to have an effect of increasing the stability of linear gradient after photocrosslinking using the polymerizable mesogen for the polymerizable liquid crystal composition, especially the polymerizable liquid crystal composition for a polymer stabilization oriented liquid display. [Reference numerals] (AA) Photocurable degree (%);(BB) Example 6;(CC) Comparative example 1;(DD) Irradiation energy (J/cm^2)

Description

[0001] The present invention relates to a polymerizable mesogen and a polymerizable liquid crystal composition containing the polymerizable mesogen and a polymerizable liquid crystal composition containing the same,

The present invention relates to a polymerizable mesogen having 2-furyl acrylate introduced therein as a photoreactive group which does not require a photoinitiator and a polymerizable liquid crystal composition containing the same.

As high-level digitization and informationization are accelerating, many information technology (IT) devices are being used in daily life, and display technology for them is also developing. Among the electronic displays that have been used in the past, CRT (Cathode Ray Tube) monitors, which have been used for TVs and computer monitors, are the most representative. CRT monitors, however, are bulky and heavy in weight, making them difficult to scale and port, have high power consumption, and are gradually replacing other flat panel displays with higher driving voltages.

LCDs (flat panel displays), plasma display panels (PDPs), and organic light emitting diodes (OLEDs) are typical examples of flat panel displays for overcoming the limitations of CRT. LCDs that incorporate liquid crystal and semiconductor technologies are thin, light, and low in power consumption, and are currently being used in large TVs, personal computer monitors, display devices of various measurement devices, portable multimedia players (PMPs) (Moving Picture Experts Group) -1 Audio Layer-3) devices, navigation devices of automobiles, mobile phones and the like. In order to realize a high-quality large-sized LCD, a wide viewing angle, a high brightness, a high contrast ratio, and a fast response speed are required.

The liquid crystal display has a liquid crystal cell and a polarizing plate. The polarizing plate is composed of a protective film and a polarizing film, which can be produced by dyeing a polarizing film made of a polyvinyl alcohol film with iodine, stretching, and laminating both sides with a protective film. For example, in a transmissive LCD, the polarizing plate may be mounted on both sides of the liquid crystal cell, and further, an optical compensation sheet having one or more optically anisotropic layers may be disposed. On the other hand, in a reflective LCD, a reflective plate, a liquid crystal cell, at least one optical compensation sheet, and a polarizing plate are arranged in this order. A liquid crystal cell is composed of a liquid crystal molecule, two substrates for sealing it, and an electrode layer for applying a voltage to the liquid crystal molecules.

The liquid crystal cell is turned on and off depending on the alignment state of the liquid crystal molecules and can be applied to both the transmissive type and the reflective type so that the liquid crystal cell can be used for various applications such as TN (Twisted nematic), IPS (in- Bend), VA (Vertically Aligned), ECB (Electrically Controlled Birefringence), STN (Super Twisted Nematic), and the like. In addition, each of these types has a unique liquid crystal arrangement and has a unique optical anisotropy. Therefore, a variety of optically anisotropic compensation films are required to compensate for changes in the optical axis of linearly polarized light due to the optical anisotropy of these liquid crystal types.

A liquid crystal compound having a polymerizable group can be applied to an optical element such as a polarizing plate or a retardation plate in order to compensate the optical anisotropy of the liquid crystal mode. Such an optical element can be obtained by polymerizing an optically anisotropic polymerizable liquid crystal in a liquid crystal state and immobilizing the state, and the polymerizable liquid crystal can be polymerized while keeping an aligned state after performing proper orientation control in a liquid crystal state. Therefore, a polymer having various optical anisotropy can be obtained by immobilizing the orientation state of the liquid crystal skeleton in a state of homogeneous orientation, hybrid orientation, oblique orientation, homeotropic orientation, twist orientation and the like.

The polymer having the homogeneous orientation can be used in combination with, for example, a half-wave plate, a quarter-wave plate, or a film having another optical function, and the polymer having a hybrid orientation can be used in a TN- It can be applied as a compensation plate. In addition, the polymer having homeotropic orientation can improve viewing angle characteristics of the polarizing plate by combining with films having other optical functions. If the direction of the optical axis is in the nz direction and the refractive index in the direction perpendicular to the optical axis direction is larger than the refractive index in the direction orthogonal to the optical axis direction, In the ellipsoid, it is classified as a positive c-plate. The positive c-plate can be applied to the optical compensation of an IPS-type liquid crystal display that is horizontally aligned in combination with a film having another optical function, in particular, for improving the viewing angle characteristics of a polarizing plate.

In addition, the liquid crystal compound having a polymerizable group can be used in liquid crystal displays of VA type widely used in high-end monitors and large-sized TVs in recent years, such as polymer stabilized alignment (PSA) or polymer stabilized vertical alignment (PS-VA: Polymer Sta Vertical Aligned) type liquid crystal displays.

A liquid crystal cell of a VA type liquid crystal display includes a host liquid crystal having a generally negative dielectric anisotropy between two transparent electrodes, and in the OFF state in which no voltage is applied, these liquid crystal molecules are oriented perpendicular to the electrode surface. On the other hand, when the voltage is applied to the electrodes, the liquid crystal molecules are oriented parallel to the electrode surface. According to the vertical and horizontal alignment phenomenon of the liquid crystal depending on whether or not the voltage is applied, the opening and closing of the light emitted from the backlight passing through the polarizing plate can be controlled. In the case of such a VA type liquid crystal display, there is a disadvantage in that the response speed is very great if the direction that is oriented in parallel when the voltage is applied to the electrode is not determined in advance.

The PSA or PS-VA type is a method for controlling the tilt of a vertically aligned liquid crystal in a liquid crystal cell, and is a method of mixing a mesogen polymerizable by ultraviolet rays together with a host liquid crystal in a liquid crystal cell. In this case, the photoreactive mesogen used must interact with the vertically aligned liquid crystal to move the host liquid crystal in the direction in which the host liquid crystal lie when voltage is applied to the electrode. If the voltage is applied, the host liquid crystal is rapidly aligned in the oblique direction, and a high-speed response can be realized.

Conventionally, Patent Document 1 - 3 discloses a polymerizable mesogen for a liquid crystal display of the PSA or PS-VA type type. However, the above-described polymerizable mesogens have a problem of low voltage retention rate and long-term reliability due to the unreacted monomer remaining un polymerized due to low photoreaction efficiency. Another problem with low absorption at long wavelengths in the photoreactor is the large exposure requirement for polymerization. These high energies are limiting the design of host liquid crystals and reactive mesogens. A photoinitiator has also been reported to solve the problem of low reactivity at long wavelengths, but the photosensitizer used acts as an impurity and causes deterioration of the device characteristics.

Patent document 4 discloses a liquid crystal display device including an oriented base film oriented to have a line gradient and an orientation film having a double layer of alignment control film having a polymerized mesogen represented by the following formula:

 P1 - A1 - (Z1 - A2) n - P2

Where

P1 and P2 are independently selected from acrylate, methacrylate and the like;

A1 and A2 are independently selected from 1,4-phenylene and naphthalene-2,6-diyl.

Further, Patent Document 5 discloses a new mesogen compound represented by the following formula:

Where

등으로부터 선택된다.
X is

And the like.

Also, in Patent Document 6, the present invention discloses a liquid crystal compound represented by the following formula.

.

.

Patent Document 4 discloses a polymer stabilized liquid crystal composition comprising a polymerizable compound represented by the following formula:

.

.

However, as described above, no polymeric mesogens incorporating a furyl acrylate group, which is a photoreactive group which does not require a photoinitiator having the structure of the compound of the present invention, has been reported.

The type of liquid crystal display constituting the liquid crystal display and / or the polymerizable film having optical anisotropy necessary therefor can be selected from polymerizable liquid crystal or polymerizable mesogen compound of a disk-shaped structure or a rod-shaped structure according to required performance.

In addition, the polymerizable liquid crystal composition should have a nematic phase and be uniform in orientation and be able to have a different orientation pattern according to the application. Further, after the polymerization, a film having optical anisotropy can be produced owing to adhesion with the substrate, optical transparency, and good weather resistance.

Furthermore, the polymerizable mesogens used in liquid crystal displays of the PSA or PS-VA type must have high photoreaction efficiency and further need to be polymerizable without a photoinitiator so that the used photoinitiator acts as an impurity and does not deteriorate the characteristics of the device. Further, since the liquid crystal cell is produced through mixing with the host liquid crystal, the solubility with the host liquid crystal must also be high. Further, a proper core is required to provide stability to the square of the mesogens tilted in the direction in which the host liquid crystal lies.

Accordingly, the present inventors have been interested in polymerizable liquid crystal compositions with a concern for polymerizable mesogens without a photoinitiator, and have found that when the polymerizable mesogens having furyl acrylate as a photoreactive group of the present invention are photo- Polymerizable at a relatively low energy, has excellent solubility with the host liquid crystal, and has an effect of improving the stability of the pre-stretch square after photo-crosslinking. Therefore, the polymerizable liquid crystal composition, in particular the polymer- The present invention has been accomplished on the basis of these findings.

Patent Document 1: Japanese Unexamined Patent Publication No. 10-513457 Patent Document 2: Japanese Unexamined Patent Publication No. 2005-60373 Patent Document 3: Japanese Unexamined Patent Publication No. 2001-527570 Patent Document 4: Korea Patent Publication No. 2011-0104416 Patent Document 5: Korea Patent Publication No. 2011-0094944 Patent Document 6: Korean Published Patent Application No. 2009-0112167 Patent Document 7: Korean Patent Publication No. 2010-0014375

It is an object of the present invention to provide polymeric mesogens incorporating furyl acrylate as photoreactive groups which do not require a photoinitiator.

It is also an object of the present invention to provide a polymerizable liquid crystal composition comprising the polymerizable mesogen.

Furthermore, it is an object of the present invention to provide a polymer stabilized alignment liquid crystal display having a liquid crystal layer containing the polymerizable liquid crystal composition.

In order to achieve the above object,

The present invention provides a polymerizable mesogen represented by the following formula:

[Formula 1]

(A and X are as described herein).

It is also an object of the present invention to provide a polymerizable liquid crystal composition comprising the polymerizable mesogen.

Furthermore, it is an object of the present invention to provide a polymer stabilized alignment liquid crystal display having a liquid crystal layer containing the polymerizable liquid crystal composition.

The polymerizable mesogen of the present invention is capable of photo-crosslinking without the need for a photoinitiator by introducing furyl acrylate as a photoreactive group, capable of polymerization at a relatively low energy, and has an excellent solubility with a host liquid crystal by introducing an asymmetric structure But it has an effect of improving the stability of the pretilt angle after photo-crosslinking. Therefore, the polymerizable liquid crystal composition can be effectively used as a polymerizable liquid crystal composition for a liquid crystal display of polymer-stabilized orientation type.

1 is a graph showing a nuclear magnetic resonance spectroscopy spectrum of a carbazole-based asymmetric polymerizable mesogen having a furyl acrylate group according to the present invention.
Fig. 2 is a graph showing the results of calculating the degree of photo-curing for the compounds of Example 6 and Comparative Example 1 in order to confirm the excellent photoreactivity of the polymerizable mesogens incorporating the furyl acrylate groups of the present invention.

Hereinafter, the present invention will be described in detail.

The present invention provides a polymerizable mesogenic compound having a furyl acrylate group introduced therein.

[Formula 1]

In Formula 1,

X is O, NH or S;

,

,

또는

이고, A is

,

,

or

ego,

In the A,

R is selected from H, -R'-, -C (= O) -R'-, -C (= O) -Ar-OR'- and C (= O) -Ar-NH- One;

R 'is a linear or branched C ₁ - C ₂₀ alkylene group;

Ar is C ₅ - and C ₃₀ arylene group;

L ₁ , L ₂ , L ₃ , L ₄ , L ₅ , L ₆ , L ₇ , L ₈ , L ₉ and L ₁₀ are independently selected from the group consisting of -H, -F, -CH ₃ and -CF ₃ Lt; / RTI >

n is an integer of 1 to 3;

Preferably, in the polymerizable mesogen represented by the above formula (1), R 'is a linear or branched alkylene group having _{1 to 10} carbon atoms, and Ar is an arylene group having _{1 to 5} carbon atoms.

More preferably, the polymerizable mesogen represented by the formula (1) is any one of the compounds represented by the formula (2)

(2)

(3)

[Chemical Formula 4]

[Chemical Formula 5]

[Chemical Formula 6]

[Formula 7]

[Formula 8]

[Chemical Formula 9]

In Formula 2-9,

X is the same as defined in the above formula (1).

Specifically, in the polymerizable mesogen represented by the above formula (1) of the present invention, the furyl acrylate group is characterized in that photo-crosslinking can be performed through a photoreaction requiring no photoinitiator. Conventionally, when a polymer stabilizing type polymerizable mesogen is used for a liquid crystal display, there is a problem that the photoinitiator acts as an impurity and deteriorates characteristics of the device due to the use of a photoinitiator for solving the problem of low reactivity at a long wavelength. However, the present invention has the effect of overcoming the above-described problems by introducing furyl acrylate capable of photo-reaction without the need for a photoinitiator.

The present invention also relates to a process for producing a compound represented by the formula (1)

Reacting a compound of formula (10) with a compound of formula (11) in an organic solvent and a catalyst to produce a compound of formula (1): < EMI ID =

[Reaction Scheme 1]

In the above Reaction Scheme 1,

X and A are as defined in the above formula (1).

Hereinafter, the above-mentioned method for producing the polymerizable mesogen will be described more specifically.

Specifically, in the process for producing a polymerizable mesogen represented by the general formula (1) of the present invention, the reaction of the general formulas (10) and (11) can be carried out in a conventional organic solvent. Any organic solvent capable of dissolving the respective reactants may be used without limitation, and the organic solvent may be used singly or in combination. As the organic solvent, dichloromethane can be preferably used.

Further, in the process for producing polymerizable mesogens represented by the above formula (1) of the present invention, in order to improve the reaction activity of the compound of formula (10) and the compound of formula (11) . The catalyst may be selected from any conventional catalysts as long as it can improve the reaction activity or the reaction rate in each production step. Preferably, a transition metal-based catalyst, an amine-based catalyst, or a mixture thereof may be used in order to obtain a product at a high yield, and more preferably pyridine or triethylamine may be used.

Further, in the process for producing a polymerizable mesogen represented by the above formula (1) of the present invention, the obtained product can be purified by removing impurities by a conventional purification method, preferably by using a chromatography method .

Further, the present invention provides a polymerizable liquid crystal composition comprising the compound of formula (1).

The present invention also provides a polymer stabilized alignment liquid crystal display comprising a liquid crystal layer comprising the polymerizable liquid crystal composition. Preferably the liquid crystal display is a liquid crystal display of the vertical orientation type.

Referring to Experimental Example 1, it can be confirmed that the polymerizable mesogen compound having furyl acrylate introduced therein as the photoreactive group represented by the formula (1) of the present invention has excellent solubility with the host liquid crystal due to slight heating. In order to control the inclination of the liquid crystal, the liquid crystal display of the polymer stabilization orientation type is a system in which a mesogen compound polymerizable by ultraviolet rays is mixed with a host liquid crystal in a liquid crystal cell. Therefore, The mesogen compound can be usefully used as a polymerizable liquid crystal composition for a liquid crystal display of a polymer stabilization orientation type.

Referring to Experimental Example 2, the polymerizable mesogen compound incorporating furyl acrylate as the photoreactive group represented by the formula (1) of the present invention has a high photoreaction efficiency, so that the voltage retention rate due to the remaining unreacted monomer and the long- Since the problem can be overcome and a large amount of exposure is not required for the polymerization, the design of the host liquid crystal and the reactive mesogen structure due to high energy is not limited, and since the photoinitiator is not used for the photopolymerization reaction, the photoinitiator acts as an impurity There is no problem of deteriorating the characteristics of the device. From this, it can be confirmed that the polymerizable mesogen compound of the present invention can be effectively used as a polymerizable liquid crystal composition of a polymer stabilized alignment liquid crystal display.

Hereinafter, the present invention will be described in more detail with reference to examples. The following examples are illustrative of the present invention, but the present invention is not limited to the following examples.

In order to confirm the high solubility of the polymerizable mesogen compound into which the furyl acrylate group is introduced by the photoreactive group of the present invention with the host liquid crystal, polymerizable mesogen compounds of the following Examples 1 to 5 were synthesized.

< Example  1 > 4 & Bis (2-furyl acryloyloxy) biphenyl  synthesis

4- tert - Butyl dimethylsilyloxy -4 ' Hydroxybiphenyl  synthesis

Dihydroxybiphenyl (3.0 g, 16.1 mmol) was dissolved in DMF (150 ml), imidazole (2.2 g, 32.2 mmol), tert-butyldimethylsilyl chloride (TBDMS- Butyldimethylsilyl chloride) (2.7 g, 17.7 mmol) were added, and the mixture was stirred at 50 占 폚 for 2 hours. After cooling to room temperature, the reaction mixture was poured into excess water to complete the reaction. After filtration, the solid was purified by column chromatography (hexane: ethyl acetate = 10: 1) to obtain a white solid (2.3 g, 48%

1 H NMR (300 MHz, CDCl 3)? 7.44-7.39 (4H, m), 6.90-6.86 (4H, m), 1.02 (9H, s), 0.24 (6H, s); MS (EI) m / z = 300.0 (M &lt; + &gt;).

4- tert - Butyl dimethylsilyloxy -4 '- (2- Furyl acryloyloxy ) Biphenyl  synthesis

Dissolve furyl acrylic acid (1.3 g, 9.2 mmol) in dichloromethane (60 ml), add 2-3 drops of DMF, lower the temperature to 0 ° C, add oxalyl chloride (0.8 ml, 9.2 mmol) To room temperature to prepare furyl acryloyl chloride.

To another reactor was added 4-tert-butyldimethylsilyloxy-4'-hydroxybiphenyl (2.3 g, 7.7 mmol), TEA (triethanolamine; triethanolamine) (10.7 ml, 76.5 mmol) and DMAP (dimethylaminopyridine 0.8 mmol) were mixed, and the resulting furyl acryloyl chloride was added dropwise thereto, followed by stirring at room temperature for 3 hours. The reaction mixture was poured into excess water to complete the reaction, followed by extraction by tube chromatography and concentration. Purification by column chromatography (HX: EA = 5: 1) gave a white solid (3.0 g, 93%):

(2H, d), 6.92 (2H, d), 6.71 (1H, d), 7.60-7.54 ), 6.56-6.50 (2H, m), 1.02 (9H, s), 0.25 (6H, s); MS (EI) m / z = 420.1 (M &lt; + &gt;).

4- Hydroxy -4 &apos; - (2- Furyl acryloyloxy ) Biphenyl  synthesis

After dissolving 4-tert-butyldimethylsilyloxy-4'- (2-furyl acryloyloxy) biphenyl (3.0 g, 7.1 mmol) in THF (100 ml), the temperature was lowered to 0 ° C, (14.3 ml, 14.3 mmol) and AcOH (acetic acid) (0.8 ml, 14.3 mmol) in tetrahydrofuran After stirring for one hour, the reaction mixture was added to an excessive amount of distilled water to terminate the reaction. The solid product was filtered, washed with water three times, and dried to obtain a white solid (1.9 g, 87%

(2H, d), 7.36 (2H, d), 7.12 (2H, d), 7.57-7.51 6.83 (2H, d), 6.75 (1H, d), 6.50 (1H, dd), 6.42 (1H, d); MS (EI) m / z = 306.4 (M &lt; + &gt;).

Synthesis of 4,4'-bis (2-furyl acryloyloxy) biphenyl

Dissolve furyl acrylate (1.0 g, 7.4 mmol) in dichloromethane (50 ml), add 2-3 drops of DMF, lower the temperature to 0 ° C, add oxalyl chloride (0.7 ml, 7.4 mmol) To room temperature to prepare furyl acryloyl chloride. To another reactor, 4-hydroxy-4'- (2-furyl acryloyl) biphenyl (1.9 g, 6.2 mmol) was dissolved in dichloromethane (30 ml) and TEA (8.6 ml, 62.0 mmol) and DMAP , 0.6 mmol), and the resulting furyl acryloyl chloride was added dropwise thereto, followed by stirring at room temperature for 3 hours. The reaction mixture was poured into an excessive amount of distilled water to terminate the reaction, and the mixture was extracted by column chromatography and then concentrated. After thoroughly dissolving in acetone (500 ml), the solid was redissolved in hexane (700 ml) to give a white solid (1.5 g, 57%):

(2H, d), 6.71 (2H, dd), 6.49 (2H, d), 7.76-7.68 , d); MS (EI) m / z = 426.1 (M &lt; + &gt;).

< Example  2 > 4,4 &quot; - Bis (2-furyl acryloyloxy) terphenyl  synthesis

4,4 ' Dimethoxydaphthalene  synthesis

Dibromo benzene (1.0 g, 4.2 mmol) was dissolved in 120 ml of methylene chloride, and 2M K ₂ CO ₃ Aqueous solution (5.3 ml) and dissolved in 17 ml ethanol-methoxyphenylboronic acid (1.6 g, 10.5 mmol) were dissolved into the order after degassing for 30 minutes, _{Pd (PPh 3) 4 (0.97g} , 4.4mmol) After raising the temperature to 100 占 폚, the mixture was stirred for 24 hours. The reaction mixture was cooled to room temperature and poured into excess water to complete the reaction. After filtration, the solid was washed with distilled water, three times with dichloromethane and methanol, and then dried to obtain a white solid (0.9 g, 75%

1 H NMR (300 MHz, DMSO- d 6)? 7.68 (4H, s), 7.67 (4H, d), 7.05 (4H, d), 3.80 (6H, s); MS (EI) m / z = 290.1 (M &lt; + &gt;).

4,4``- Dihydroxydaphthalene  synthesis

4,4'-dimethoxytriphenyl (1.0 g, 3.4 mmol) was dissolved in dichloromethane (50 ml), and the temperature was lowered to -78 ° C. BBr 3 (1.7 ml, 17.2 mmol) was added to 10 ml of dichloromethane Diluted and added dropwise. Then, the reaction temperature was raised to room temperature and stirred for 10 hours. The reaction mixture was poured into excess water to complete the reaction. After filtration, the solid was washed with distilled water, dichloromethane and methanol three times, and then dried to obtain a white solid (0.7 g, 79%

1 H NMR (300 MHz, CD 3 OD + DMSO-d 6)? 7.57 (4H, s), 7.50 (4H, d), 6.86 (4H, d); MS (EI) m / z = 262.1 (M &lt; + &gt;).

4- tert - Synthesis of tert-butyl-dimethyl-silyloxy -4``- hydroxyl sheeter control phenyl

(1.2 g, 17.5 mmol) and TBDMS-Cl (1.6 g, 10.5 mmol) were added to a DMF (60 ml) Followed by stirring at 50 ° C for 2 hours. After cooling to room temperature, the reaction mixture was poured into excess water to complete the reaction. After filtration, the solid was purified by column chromatography to obtain a white solid (1.4 g, 43%):

1 H NMR (300 MHz, CDCl 3)? 7.60 (4H, s), 7.55-7.48 (4H, m), 6.95-6.89 (4H, m), 1.02 (9H, s), 0.24 (6H, s); MS (EI) m / z = 376.5 (M &lt; + &gt;).

4- tert - Butyl dimethylsilyloxy -4 '- (2- Furyl acryloyloxy ) Terphenyl  synthesis

Dissolve furyl acrylate (0.6 g, 4.1 mmol) in dichloromethane (50 ml), add 2-3 drops of DMF, lower the temperature to 0 ° C, add oxalyl chloride (0.4 ml, 4.1 mmol) To room temperature to prepare furyl acryloyl chloride.

To another reactor was added 4-tert-butyldimethylsilyloxy-4'-hydroxystearphenyl (1.3 g, 3.5 mmol), TEA (4.8 ml, 34.5 mmol) and DMAP (42 mg, 0.3 mmol) The resulting furyl acryloyl chloride was added dropwise thereto, followed by stirring at room temperature for 3 hours. The reaction mixture was poured into excess water to complete the reaction, followed by extraction by tube chromatography and concentration. Purification by column chromatography (HX: EA = 5: 1) gave a white solid (1.5 g, 88%):

(1H, d), 6.97 (2H, d), 6.71 (1H, d), 7.71 1H, dd), 6.50 (1H, d), 0.98 (9H, s), 0.23 (6H, s); MS (EI) m / z = 496.2 (M &lt; + &gt;).

4- Hydroxy -4 '- (2- Furyl acryloxy ) Terphenyl  synthesis

4-tert-Butyldimethylsilyloxy-4'-2 (2-furyl acryloyloxy) terphenyl (1.5 g, 3.0 mmol) was dissolved in THF (50 ml), the temperature was lowered to 0 ° C, A solution of nBu4NF (9.0 ml, 9.0 mmol) and glacial AcOH (0.5 ml, 9.0 mmol) was slowly added dropwise. After stirring for one hour, the reaction mixture was added to an excessive amount of distilled water to terminate the reaction. The solid product was filtered, washed with water three times, and then dried to obtain a white solid (0.9 g, 78%

(2H, d), 7.31 (2H, d), 7.10 (1H, d) 1H, d), 6.88 (2H, d), 6.71 (1H, dd), 6.50 (1H, d); MS (EI) m / z = 382.1 (M &lt; + &gt;).

4,4``- Bis (2-furyl acryloyloxy) terphenyl  synthesis

Dissolve furyl acrylate (0.4 g, 2.8 mmol) in dichloromethane (50 ml), add 2-3 drops of DMF, lower the temperature to 0 ° C, add oxalyl chloride (0.3 ml, 2.8 mmol) To room temperature to prepare furyl acryloyl chloride.

To another reactor, 4-hydroxy-4 '' - (2-furyl acryloyloxy) tolphenyl (29 mg, 0.2 mmol) was added and the resulting furyl acryloyl chloride was added dropwise. Respectively. The reaction mixture was poured into an excessive amount of distilled water to terminate the reaction, and the mixture was extracted by column chromatography and then concentrated. Purification by column chromatography gave a white solid (0.6 g, 49%).

(2H, d), 7.71 (2H, d), 7.71 (2H, d), 7.74 , &lt; / RTI &gt; dd), 6.50 (2H, d); MS (FAB) m / z = 502 (M &lt; + &gt;).

< Example  3> 2,6- Bis (2-furyl acryloyloxy) naphthalene  synthesis

2-( tert - Butyldimethylsilyloxy ) -6- Hydroxynaphthalene  synthesis

After adding imidazole (2.6 g, 37.5 mmol) and TBDMS-Cl (5.7 g, 37.5 mmol), DMF (250 g) Lt; / RTI &gt; After cooling to room temperature, the reaction mixture was poured into excess water to complete the reaction. After filtration, the solid was purified by column chromatography (HX: EA = 5: 1) to obtain a white solid (4.6 g, 54%

1 H NMR (300 MHz, CDCl 3)? 7.62-7.54 (2H, dd), 7.15-7.03 (4H, m), 1.04 (9H, s), 0.25 (6H, s); MS (EI) m / z = 274.0 (M &lt; + &gt;).

2-( tert .- Butyl dimethylsilyloxy ) -6- (2- Furyl acryloyloxy ) Synthesis of naphthalene

After dissolving 2.8 g (20.1 mmol) of furyl acrylate in 150 ml of dichloromethane, 2-3 drops of DMF were added, the temperature was lowered to 0 ° C, oxalyl chloride (1.8 ml, 20.1 mmol) To room temperature to prepare furyl acryloyl chloride.

To another reactor was added a mixture of 2- (tert-butyldimethylsilyloxy) -6-hydroxy naphthalene (4.6 g, 16.8 mmol), TEA (23.4 ml, 167.6 mmol) and DMAP (0.2 g, 1.7 mmol) Furyl acryloyl chloride was added dropwise thereto, followed by stirring at room temperature for 3 hours. The reaction mixture was poured into excess water to complete the reaction, followed by extraction by tube chromatography and concentration. Purification by column chromatography HX: EA = 5: 1) afforded a white solid (5.8 g, 88%).

(2H, m), 7.11-7.07 (1H, dd), 7.55-7.53 (2H, m), 7.25-7.20 , 6.70 (1H, d), 6.57 (1H, d), 6.51 (1H, dd), 1.02 (9H, s), 0.24 (6H, s); MS (EI) m / z = 394.2 (M &lt; + &gt;).

2-( Hydroxy ) -6- (2- Furyl acryloyloxy ) Synthesis of naphthalene

After dissolving 2- (tert.-butyldimethylsilyloxy) -6- (2-furyl acryloyloxy) naphthalene (5.8 g, 14.7 mmol) in THF (150 ml) A solution of nBu4NF (44 ml, 44.1 mmol) and AcOH (2.5 ml, 44.1 mmol) was slowly added dropwise. After stirring for one hour, the reaction mixture was added to an excessive amount of distilled water to terminate the reaction. The solid product was filtered, washed with water three times, and then dried to obtain a white solid (4.0 g, 97%

1 H NMR (300 MHz, DMSO- d 6)? 9.33 (IH, s), 7.73 (1H, d), 7.67-7.59 (3H, m), 7.49 (1H, d), 7.19-7.11 (3H, m), 6.80 ); MS (EI) m / z = 280.0 (M &lt; + &gt;).

2,6- Bis (2-furyl acryloyloxy) naphthalene  synthesis

Dissolve furyl acrylic acid (2.4 g, 17.1 mmol) in dichloromethane (100 ml), add 2-3 drops of DMF, lower the temperature to 0 ° C, add oxalyl chloride (1.5 ml, 17.1 mmol) To room temperature to prepare furyl acryloyl chloride.

In another reactor, 2- (hydroxy) -6- (2-furyl acryloyloxy) naphthalene (4.0 g, 14.3 mmol) was dissolved in dichloromethane (100 ml) and TEA (19.9 ml, 142.7 mmol), DMAP mg, 1.4 mmol) were mixed, and the resulting furyl acryloyl chloride was added dropwise thereto, followed by stirring at room temperature for 3 hours. The reaction mixture was poured into an excessive amount of distilled water to terminate the reaction, extracted with dichloromethane, and then concentrated to 1/2. The solid product after concentration was filtered and dried to give a white solid (2.5 g, 44%):

(2H, d), 7.77 (2H, d), 7.41 (2H, d), 7.11 (2H, d) ), 6.72 (2H, dd), 6.53 (2H, d); MS (EI) m / z = 400.1 (M &lt; + &gt;).

< Example  4> 2,5-Bis [4- (2- Furyl acryloyloxy ) Phenyl ] Thiophene  synthesis

2,5- Of bis (4-methoxyphenyl) thiophene  synthesis

Dibromo thiophene (5.3 g, 21.9 mmol) was dissolved in xylene (120 ml), and a 2M aqueous K ₂ CO ₃ solution (25 ml) and 80 ml of ethanol-dissolved methoxyphenylboronic acid (10.0 g, 65.7 mmol) After degassing for 30 minutes, Pd (PPh ₃ ) (45.1 g, 4.4 mmol) was added, the temperature was raised to 100 ° C and the mixture was stirred for 24 hours. The reaction mixture was cooled to room temperature and poured into excess water to complete the reaction. After filtration, the solid was washed three times with distilled water, dichloromethane and methanol, and then dried to obtain a pale green solid (6.0 g, 93%

D), 7.36 (2H, s), 7.01 (4H, d), 3.79 (6H, s); MS (EI) m / z = 296.1 (M &lt; + &gt;).

2,5- Of bis (4-hydroxyphenyl) thiophene  synthesis

2,5-bis (4-methoxyphenyl) thiophene (6.0 g, 20.3 mmol) and then the temperature was reduced to -78 ℃ was dissolved in dichloromethane (200 ml) BBr ₃ (9.8 ml, 101.3 mmol) was diluted with 30 ml of dichloromethane and added dropwise. Then, the reaction temperature was raised to room temperature and stirred for 10 hours. The reaction mixture was poured into excess water to complete the reaction. After filtration, the solid was washed several times with dichloromethane and dried to obtain a brown solid (5.1 g, 94%):

1 H NMR (300 MHz, CD 3 OD + DMSO-d 6)? 7.40 (4H, d), 7.08 (2H, s), 6.75 (4H, d); MS (EI) m / z = 268.5 (M &lt; + &gt;).

2- (4- Hydroxyphenyl ) -5- (4- tert - Butyl dimethylsilyloxyphenyl ) Thiophene  synthesis

Imidazole (2.5 g, 37.3 mmol) and TBDMS-Cl (4.2 g, 28.0 mmol) were added to the solution after dissolving 2,5-bis (4-hydroxyphenyl) thiophene Followed by stirring at 50 ° C for 2 hours. After cooling to room temperature, the reaction mixture was poured into excess water to complete the reaction. After filtration, the solid was purified by column chromatography to obtain a pale yellow solid (4.0 g, 56%):

(1H, d), 7.25 (1H, d), 6.96-6.87 (4H, m), 1.02 (9H, s), 0.25 (6H, s); MS (EI) m / z = 382.1 (M &lt; + &gt;).

2- [4- (2- Furyl acryloyloxy ) Phenyl ] -5- (4- tert - Butyl dimethylsilyloxyphenyl ) Thiophene  synthesis

After dissolving furyl acrylic acid (1.6 g, 11.5 mmol) in MC (100 ml) and adding 2 ~ 3 drops of DMF, the temperature was lowered to 0 ° C and oxalyl chloride (1.0 ml, 11.5 mmol) &Lt; / RTI &gt; to produce furyl acryloyl chloride.

To another reactor was added 2- (4-hydroxyphenyl) -5- (4-tert-butyldimethylsilyloxyphenyl) thiophene (4 g, 10.5 mmol), TEA (14.6 ml, 104.6 mmol) 1.0 mmol) were mixed, and the resulting furyl acryloyl chloride was added dropwise thereto, followed by stirring at room temperature for 3 hours. The reaction mixture was poured into an excess amount of water to terminate the reaction and then extracted with MC and concentrated. Purification by column chromatography (HX: EA = 5: 1) gave a pale yellow solid (3.8 g, 72%):

(1H, d), 7.36 (1H, d), 7.76 (1H, d) ), 7.28 (2H, d), 7.00 (1H, d), 6.97 ; MS (EI) m / z = 502.1 (M &lt; + &gt;).

2- [4- (2- Furyl acryloyloxy ) Phenyl ] -5- (4- Hydroxyphenyl ) Thiophene  synthesis

Thiophene (3.8 g, 7.6 mmol) was dissolved in THF (100 ml) at room temperature, and the resulting solution was stirred at room temperature for 2 hours. After lowering to 0 ° C, a pre-mixed solution of nBu 4 NF (22.7 ml, 22.7 mmol) and AcOH (1.3 ml, 22.7 mmol) was slowly added dropwise. After stirring for one hour, the reaction mixture was added to an excessive amount of distilled water to terminate the reaction. The solid product was filtered, washed with water three times, and dried to obtain a yellow solid (2.9 g, 99%

(3H, m), 7.34 (1H, d), 7.27 (1H, d) (2H, d), 7.10 (1H, d), 6.84 (2H, d), 6.71 (1H, dd), 6.48 (1H, d); MS (EI) m / z = 388.0 (M &lt; + &gt;).

2,5-bis [4- (2- Furyl acryloyloxy ) Phenyl ] Thiophene  synthesis

Dissolve furyl acrylate (0.81 g, 5.9 mmol) in dichloromethane (100 ml), add 2-3 drops of DMF, lower the temperature to 0 ° C, add oxalyl chloride (0.52 ml, 5.9 mmol) To room temperature to prepare furyl acryloyl chloride.

In another reactor, 1.9 g (4.9 mmol) of 2- [4- (2-furyl acryloyloxy) phenyl] -5- (4- hydroxyphenyl) thiophene, TEA (6.8 ml, 48.9 mmol) 59.8 mg, 0.5 mmol) were mixed, and the resulting furyl acryloyl chloride was added dropwise thereto, followed by stirring at room temperature for 3 hours. The reaction mixture was poured into excess distilled water to complete the reaction, extracted with dichloromethane and concentrated. Purification by column chromatography gave a yellow solid (2.1 g, 84%):

(2H, s), 7.30 (4H, d), 7.10 (2H, d), 7.74 d), 6.71 (2H, dd), 6.48 (2H, d); MS (FAB) m / z = 509 (M &lt; + &gt;).

< Example  5 > 2- (4- Furyl acryloyloxy ) Phenyl -7- Of furyl acryloyloxycarbazole  synthesis

(4.5 g, 16.2 mmol), 4- (dimethylamino) pyridine (8.6 g, 71.3 mmol), furyl acryloylic acid (9 g, 48.6 mmol ) Is diluted with 200 ml of dichloromethane and 50 ml of DMF and stirred. After 20 minutes, DCC (14.8 g, 71.3 mmol) is added dropwise. After 24 hours, filter the by-product and remove the solvent. (2.7 g) as a pale yellow solid, 2- (4-furyl acryloyloxy) phenyl-7-furyl acryloyloxycarbazole was isolated by silica gel column in hexane-ethyl acetate (3/1) Obtained:

_{^{1 H NMR (Acetone-d 6}} , 300MHz) δ = 10.55 (s, 1H, NH), 8.20-8.14 (q, 2H, ArH), 7.81-7.78 (m, 1H, ArH), 7.70-7.67 (d, 1H, ArH), 7.32-7.30 (m, 2H, ArH), 7.03-7.01 (dd, 1H, ArH), 7.38-7.38 6.99-6.98 (m, 2H, ArH), 6.66-6.51 (m, 2H, ArH), 6.51-6.48 (q, 2H, .dbd.CH); MS m / z 515 (M ^&lt; ^{+ &} gt ^; ) [

In order to comparatively evaluate the improved photoreactivity of the polymerizable mesogens having a furyl acrylate group introduced by the photoreactive group of the present invention, Example 6 in which a furyl acrylate group was introduced as the photoreactive group and methacrylate was introduced into the photoreactive group A compound of Comparative Example 1 was synthesized.

< Example  6> 1,6- Vis (2- Furyl acryloyloxy ) Hexane (HX- FA ) synthesis

Dissolve furyl acrylic acid (7.0 g, 50.8 mmol) in dichloromethane (300 ml), add 2-3 drops of DMF, lower the temperature to 0 ° C, add oxalyl chloride (4.5 ml, 50.8 mmol) To room temperature to prepare furyl acryl chloride.

In another reactor, 1,6-hexanediol (2.0 g, 16.9 mmol) was dissolved in dichloromethane (100 ml), TEA (23.6 ml, 169.2 mmol) and DMAP (0.2 g, 1.7 mmol) Acryl chloride was added dropwise thereto, followed by stirring at room temperature for 3 hours. The reaction mixture was poured into an excess amount of distilled water to complete the reaction. The reaction mixture was extracted with dichloromethane and then separated by column chromatography (HX: EA = 20: 1 to 8: 1) to obtain a pale yellow solid (4.8 g, 79.1% :

_{^{1 H NMR 300MHz, DCl 3)}} δ 7.47 (2H, d), 7.44 (2H, d), 6.61 (2H, d), 6.47 (2H, dd), 6.34 (2H, d), 4.21 (4H, t) , 1.74 (4H, quint), 1.47 (4H, m); MS (EI) m / z = 358 (M ^&lt; ^{+ &} gt ^; ).

< Comparative Example  1> 1,6- Bis (methacryloyloxy) hexane  ( HX - MA ) synthesis

Dissolve methacrylic acid (5.7 g, 67.7 mmol) in dichloromethane (300 ml), add 2-3 drops of DMF, lower the temperature to 0 ° C and slowly add oxalyl chloride (6.0 ml, 67.7 mmol) Methacryloyl chloride was prepared by raising the temperature to room temperature.

To another reactor, 1,6-hexanediol (2.0 g, 16.9 mmol) was dissolved in dichloromethane (100 ml), TEA (23.6 ml, 169.2 mmol) and DMAP (0.2 g, 1.7 mmol) The mixture was stirred at room temperature for 3 hours. The reaction mixture was poured into an excessive amount of distilled water to complete the reaction. The reaction mixture was extracted with dichloromethane and then separated into a liquid (1.7 g, 39.5%) by a column chromatography (HX: EA = 50: 1)

^{1 H NMR (300 MHz, CDCl} 3) δ 6.09 (2H, m), 5.55 (2H, m), 4.16 (4H, t), 1.94 (6H, m), 1.71 (4H, quint), 1.45 (4H, m).

< Experimental Example  1> Solubility evaluation with host liquid crystal

In order to confirm the high solubility of the polymerizable mesogens into which the furyl acrylate groups were introduced by the photoreactive groups of the present invention with the host liquid crystals, the polymerizable mesogens of Examples 1 to 5 were evaluated for solubility with the host liquid crystal, The results are shown in Table 1 below.

To evaluate the solubility of the polymerizable mesogens of Examples 1 to 5 with the host liquid crystal, 0.5 wt.% Of the polymerizable mesogens of Examples 1 to 5 were mixed with a liquid crystal for vertical alignment (MLC-6608, Merck) After stirring for 1 hour, the mixture was visually observed. In order to evaluate the stability at low temperature, the change was observed after standing at -30 ° C for 3 days. When the solubility of the polymerizable mesogens observed in Examples 1 to 5 was very good, the solubility of the host liquid crystal was - (⊚), the case of melting slightly upon heating - (O) and the case of not dissolving - Respectively.

division Room temperature -30 ° C Example 1 O O Example 2 O O Example 3 X X Example 4 O O Example 5 O O

As a result, as shown in Table 1, the polymerizable mesogens having naphthalene as a core of Example 3 did not dissolve in the host liquid crystal at room temperature and -30 캜, while those of Examples 1 - 2 and 4 - 5 The polymerizable mesogens having biphenyl, tolphenyl, dithiophene and carbazole core, respectively, can be dissolved in the host liquid crystal at slightly room temperature and at a temperature of -30 ° C.

From this, it can be seen that the polymerizable mesogen compounds of Examples 1 - 2 and 4 - 5 of the present invention have excellent solubility in the vertically aligned host liquid crystal due to the asymmetric structure.

Therefore, the polymerizable mesogen compound having the furayl acrylate introduced into the photoreactive group of the present invention can be used for a liquid crystal display of a polymer stabilization orientation type which controls the inclination of the host liquid crystal by mixing the host liquid crystal and a mesogen compound which can be polymerized by ultraviolet rays It can be confirmed that it can be usefully used as a polymerizable liquid crystal composition.

< Experimental Example  2> FT - IR Using Photoreactive  evaluation

In order to comparatively evaluate the improved photoreactivity of the polymerizable mesogens incorporating the furyl acrylate groups in the photoreactive group of the present invention, the photoreactivity of the compounds of Example 6 and Comparative Example 1 was evaluated using FT-IR, The results are shown in Table 2 and FIG.

The compounds of Example 6 and Comparative Example 1 were dissolved in 1,2-dichloroethane at 10 wt.%, Respectively, coated on KBr pellets, irradiated with UV (365 nm) from 1 to 50 J, FT-IR spectrum was obtained. The degree of photo-curing was calculated from the area ratio of C = O band and C = C band in the obtained spectrum, and the results are shown in Table 2.

division 0J 1J 2J 3J 5J 10J 20J 30J 50J Example 6
Photocuring degree (%) 0(%) -2 35 53 72 80 83 80 78 Comparative Example 1
Photocuring degree (%) 0 10 14 14 16 17 16 18 18

As a result, as shown in Table 2 and FIG. 2, the polymerizable mesogens of Example 6 of the present invention exhibited remarkably high degree of photo-curing up to an ultraviolet irradiation energy of 20 J as the ultraviolet irradiation energy was increased, The maximum degree of curing was 83%. On the other hand, the compound having methacrylate of Comparative Example 1 as a photoreactive group showed a slight increase in the degree of photo-curing and a maximum degree of photo-curing of 18% as the ultraviolet irradiation energy was increased.

From this, it can be seen that the polymerizable mesogens into which the furyl acrylate was introduced as the photoreactive group of Example 6 of the present invention had better photoreactivity than the methacrylate-introduced compound known as the conventional photoreactive group of Comparative Example 1 without a photoinitiator .

Therefore, the polymerizable mesogens incorporating the methoxyacrylate group of the present invention have a high photoreaction efficiency even at relatively low energy, so that the voltage maintenance rate due to unreacted monomers, which is a problem of the polymerizable mesogens used in conventional polymer stabilization orientation types Degradation and long term reliability problems and does not limit the structural design of host liquid crystals and reactive mesogens due to high energy because it does not require much exposure dose for polymerization. Therefore, the polymerizable compound having the methoxyacrylate group introduced thereinto of the present invention can be usefully used as a polymerizable liquid crystal composition for a liquid crystal display of a polymer stabilization orientation type.

Claims (10)

A polymerizable mesogen represented by the following formula (1):
[Chemical Formula 1]

(In Formula 1,
X is O, NH or S;
A is

,

,

or

ego,
In the A,
R is selected from H, -R'-, -C (= O) -R'-, -C (= O) -Ar-OR'- and C (= O) -Ar-NH- One;
R 'is a linear or branched C ₁ - C ₂₀ alkylene group;
Ar is C ₅ - and C ₃₀ arylene group;
L ₁ , L ₂ , L ₃ , L ₄ , L ₅ , L ₆ , L ₇ , L ₈ , L ₉ and L ₁₀ are independently selected from the group consisting of -H, -F, -CH ₃ and -CF ₃ Lt; / RTI &gt;
and n is an integer of 1 to 3).
The method of claim 1,
R` is C ₁ - C _10, and a linear or branched alkylene group;
Ar is a C ₅ -C ₆ monocyclic arylene group;
L ₁ , L ₂ , L ₃ , L ₄ , L ₅ , L ₆ , L ₇ , L ₈ , L ₉ and L ₁₀ are independently selected from the group consisting of -H, -F, -CH ₃ and -CF ₃ Polymeric mesogen which is any one of which becomes.
The method of claim 1,
The polymerizable mesogen represented by the general formula (1) is any one selected from the group consisting of compounds represented by the following general formulas (2-9):
(2)

(3)

[Chemical Formula 4]

[Chemical Formula 5]

[Chemical Formula 6]

(7)

[Chemical Formula 8]

[Chemical Formula 9]

(2 to 9)
X is as defined in claim 1).
The method of claim 1,
Wherein said polymerizable mesogen is photopolymerizable without the need for a photoinitiator.
As shown in Scheme 1 below,
A process for producing a polymerizable mesogen represented by the following formula (1), comprising the step of reacting a compound of the formula (10) with a compound of the formula (11) in an organic solvent and a catalyst to prepare a compound of the formula
[Reaction Scheme 1]

(In the above Reaction Scheme 1,
X and A are as defined in claim 1).
The method of claim 5,
Wherein the organic solvent is dichloromethane. &Lt; RTI ID = 0.0 &gt; 21. &lt; / RTI &gt;
The method of claim 5,
Wherein the catalyst is pyridine or triethylamine. &Lt; RTI ID = 0.0 &gt; 11. &lt; / RTI &gt;
A polymerizable liquid crystal composition comprising a polymerizable mesogen represented by the following formula
[Chemical Formula 1]

(In Formula 1,
X and A are as defined in claim 1).
A polymer-stabilized alignment liquid crystal display comprising a liquid crystal layer comprising the polymerizable liquid crystal composition of claim 8.
10. The liquid crystal display of claim 9, wherein the liquid crystal display is a vertical alignment type liquid crystal display.

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