KR20190012531A - Liquid crystal compound and liquid crystal composition containing the same - Google Patents

Abstract

The present invention relates to a liquid crystal composition which does not lower the refractive index anisotropy (n) and a nematic phase-isotropic liquid crystal phase transition temperature (Tni), and has sufficiently small rotation viscosity (γ1), a large elastic modulus (K_33) and negative dielectric anisotropy (Δε) with a large absolute value. The composition can be used in a liquid crystal display in a vertical alignment (VA) mode or a polymer stabilized alignment (PSA) mode.

Description

TECHNICAL FIELD [0001] The present invention relates to a liquid crystal compound and a liquid crystal composition containing the same. BACKGROUND OF THE INVENTION [0002]

The present invention relates to a nematic liquid crystal compound having a negative dielectric anisotropy (DELTA epsilon) useful as a liquid crystal display material, a liquid crystal composition comprising the same, and an electro-optical device using the same, especially a VA (Vertical Alignment) Polymer Stabilized Alignment).

BACKGROUND ART [0002] Liquid crystal displays (LCDs) are one of the most widely used flat panel displays. The liquid crystal display device can turn ON / OFF by determining the direction of the liquid crystal molecules in the liquid crystal layer by controlling the electric field in the liquid crystal layer by applying a voltage to the electric field generating electrode and adjusting the transmittance of light passing through the liquid crystal layer. It can be applied to both transmissive and reflective types and can be used for various applications such as TN (Twisted nematic), IPS (in-Plane Switching), OCB (Optically Compensatory Bend), VA (Vertically Aligned), ECB (Electrically Controlled Birefringence) ) And the like are being developed.

Among them, a VA (Vertical Alignment) mode liquid crystal display device includes a liquid crystal having a negative dielectric anisotropy between two transparent electrodes. When the voltage is not applied, these liquid crystal molecules are vertically oriented on the electrode surface, 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 the presence or absence of the voltage application, it is possible to control the opening and closing of the light emitted from the backlight passing through the polarizer. However, if the direction is not predetermined in parallel, There is a disadvantage.

As a method for overcoming the disadvantage of such a VA mode liquid crystal display device, it is possible to improve the response speed by preliminarily determining the directionality of the mother liquid crystal by polymerizing the polymerizable compound in the mother liquid crystal and then polymerizing the voltage in the on state A liquid crystal display device technology of a polymer stabilized alignment (PSA) or a polymer stabilized-vertically aligned (PS-VA) mode is attracting attention. At this time, the polymerizable compound used must be moved in the direction in which the host liquid crystal lie when the voltage is applied to the electrode through interaction with the vertically aligned liquid crystal. When the slope is induced and then cured through light irradiation, the slope remains constant even when the voltage is not applied, and when the voltage is applied again, the liquid crystal of the mother substrate can be rapidly aligned in the oblique direction, thereby realizing a high speed response.

Generally, a liquid crystal composition used for implementing a PSA mode liquid crystal display device contains a polymerizable compound, and the liquid crystal composition should maintain a stable liquid crystal state at a low temperature. If a polymerizable compound is precipitated from a liquid crystal composition containing a polymerizable compound at a low temperature, the PSA mode can not be realized. Therefore, there is a great demand for a polymerizable compound having a high solubility in a liquid crystal composition, a low melting point, and stability at low temperature when mixed with a liquid crystal composition.

Further, in the PSA mode, when a liquid crystal composition containing a polymerizable compound is injected and irradiated with ultraviolet rays, the polymerizable group of the polymerizable compound reacts with ultraviolet rays. After the ultraviolet ray irradiation, the pretilt angle of the liquid crystal changes to a lower angle at 90 degrees, and a faster response time can be realized as the pretilt angle lower than 90 degrees is exhibited.

In Patent Document JP2006-301643, it is disclosed that the response speed of a homeotropic liquid crystal cell is improved by using a liquid crystal material having a high index (FoM) represented by [Formula 1]. Since the refractive index anisotropy (Δn) in the equation is a constant determined by the cell gap of the LCD, the comparative properties of pure liquid crystal alone are determined by K33 / γ1. When K33 /? 1 is large or? 1 / K33 is small, the response speed of the liquid crystal composition is improved.

[Formula 1]

In view of the above, in a liquid crystal composition requiring a high-speed response such as a liquid crystal display device, it is possible to obtain a solid-nematic phase transition temperature (Tcn) without decreasing the refractive index anisotropy (? N) and the nematic phase-isotropic liquid crystal phase transition temperature ) Is sufficiently low, the rotational viscosity? 1 is required to be sufficiently small, and the elastic constant (K ₃₃ ) is required to be large.

The present invention is characterized in that it has a sufficiently small rotational viscosity (? 1), a large elastic modulus (K ₃₃ ) and a large absolute value (? ₃₃ ) without lowering the refractive index anisotropy (? N) and the nematic phase-isotropic liquid crystal phase transition temperature In a VA mode, a PSA mode, a PS-VA mode, an IPS mode, or an FFS mode using the liquid crystal composition, a liquid crystal composition having a dielectric anisotropy (DELTA epsilon) And a liquid crystal display device.

One aspect of the present invention provides a liquid crystal compound represented by the following formula (1).

[Chemical Formula 1]

In Formula 1,

R ₁ and R ₂ are each independently an alkyl or alkoxy radical having 1 to 15 carbon atoms and wherein at least one -CH ₂ - group in the radical is independently selected from the group consisting of -C = C- , -CF ₂ O-, -CH = CH-, -O-, -CO-O- or -OC-O-, or one or more hydrogen atoms may be substituted with halogen,

Ring A ₁ is 1,4-cyclohexylene or 1,4-cyclohexenylene,

L ₁ and L ₂ are each independently hydrogen, a fluorine, an alkyl radical or an alkoxy radical, and the -CH ₂ - groups in the radicals may be substituted with one or more halogens.

One aspect of the present invention provides a liquid crystal composition comprising at least one liquid crystal compound represented by Formula 1.

In one embodiment of the present invention, the liquid crystal composition may further include at least one liquid crystal compound represented by the following general formulas (2) to (4)

(2)

(3)

[Chemical Formula 4]

In the above Chemical Formulas 2 to 4,

R ₁ 'and R ₂ ' each independently represent a radical of any one of alkyl having 1 to 7 carbon atoms, or one or more hydrogen atoms of the radical are substituted with halogen or one or more -CH ₂ - -O-CO-, or -O-CO-O-, in which R <

R ₃ to R ₆ are each independently an alkyl or alkoxy radical having 1 to 15 carbon atoms and at least one CH ₂ group in the radicals is independently selected from the group consisting of -C = C-, -CF ₂ O-, -CH = CH-, -O-, -CO-O- or -OC-O, or at least one hydrogen atom may be substituted with halogen,

Z ₅ is a single bond, or a group represented by -CH ₂ O-, -OCH ₂ -, -CH ₂ CH ₂ -, -CF ₂ O-, -OCF ₂ -, -CH═CH-, -CF═CF-, -C = C-, -COO-, -OCO-,

Rings A and B are each independently 1,4-cyclohexylene, or 1,4-phenylene,

Rings C, D, and E are each independently any one of the following structures:

The rings F, G and I are each independently 1,4-cyclohexylene, 1,4-phenylene or 1,4-phenylene in which one fluorine is substituted,

(F) is hydrogen or F,

e and f are not are each independently an integer of 0 or 1, with the proviso that e is 1 and f is 0, and Z ₅ are united unity when ring C is phenyl,

g and h are each independently an integer of 0 or 1, and g + h is an integer of 1 or more.

In one embodiment of the present invention, the liquid crystal composition may further include at least one compound selected from compounds represented by the following general formulas (5) and (6).

[Chemical Formula 5]

[Chemical Formula 6]

In the above formulas (5) and (6)

R ₇ is alkyl having 1 to 12 carbon atoms,

R ₈ , and R ₉ are each independently hydrogen, oxygen, alkyl having 1 to 12 carbon atoms,

Ring J is cyclohexyl or phenyl,

i is an integer of 0 or 1,

k is an integer of 1 to 12;

In one embodiment of the present invention, there is provided a liquid crystal composition further comprising a polymerizable compound represented by the following formula (7) in the liquid crystal compound represented by the formula (1).

(7)

P ₁ -Sp ₁ - (K ₁ -Y ₁ ) _a - (K ₂ -Y ₂ ) _b - (K ₃ -Y ₃ ) _c -Sp ₂ -P ₂

In Formula 7,

P ₁ and P ₂ are each independently a polymerizable functional group, a C 1 -C 9 alkyl, alkenyl having 2 to 9, H, F, Cl, or means the CN, however, at least one of P ₁ and P ₂ are polymerized Functional group,

Sp ₁ and Sp ₂ are each independently a single bond, a radical of any of the alkyl of 1 to 15 carbon atoms, or a radical of which at least one hydrogen atom is substituted by halogen or one or more -CH ₂ - -O-, -O-CO- or -O-CO-O-, in the presence of a base,

Y ₁ to Y ₃ are each independently _{-CH 2 CH 2 -, -CH =} CH-, -CH 2 O-, -OCH 2 -, -C = C-, -CH 2 CF 2 -, -CHFCHF-, -CF ₂ CH ₂ -, -CH ₂ CHF-, -CHFCH ₂ -, -C ₂ F ₄ -, -O-, -COO-, -OCO-, -CF ₂ O-, -OCF ₂ - ego,

K ₁ to K ₃ are each independently an aromatic ring or a heterocyclic ring composed of 5 to 7 carbons, and hydrogen in the ring structure may be substituted with fluorine or an alkoxy radical having 1 to 15 carbon atoms,

a, b, and c are each independently an integer of 0 to 2, and a + b + c is 1 to 3.

According to an aspect of the present invention, there is provided a liquid crystal display comprising at least one compound represented by Formula 1 or the liquid crystal composition.

The liquid crystal composition of the present invention has a sufficiently small rotational viscosity (? 1), a large elastic modulus (K ₃₃ ), a small absolute value (? 1) and a low viscosity Has a large negative dielectric anisotropy (DELTA epsilon). Such a liquid crystal composition can provide a liquid crystal composition optimized for a liquid crystal display of various modes, especially a liquid crystal display of a VA mode, a PSA mode, a PS-VA mode, an IPS mode or an FFS mode.

1 is a cross-sectional view schematically showing a liquid crystal display device according to an embodiment of the present invention.

Hereinafter, embodiments and examples of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains.

It should be understood, however, that the present invention may be embodied in many different forms and is not limited to the embodiments and examples described herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

Throughout this specification, when a member is " on " another member, it includes not only when the member is in contact with the other member, but also when there is another member between the two members.

Throughout this specification, when an element is referred to as " including " an element, it is understood that the element may include other elements as well, without departing from the other elements unless specifically stated otherwise. The terms " about ", " substantially ", etc. used to the extent that they are used throughout the specification are intended to be taken to mean the approximation of the manufacturing and material tolerances inherent in the stated sense, Accurate or absolute numbers are used to help prevent unauthorized exploitation by unauthorized intruders of the referenced disclosure. The word " step (or step) " or " step " used to the extent that it is used throughout the specification does not mean " step for.

Throughout this specification, the term " combination thereof " included in the expression of the machine form means one or more combinations or combinations selected from the group consisting of the constituents described in the expression of the machine form, And the like.

Throughout this specification, the description of "A and / or B" means "A or B, or A and B". Furthermore, unless otherwise stated, the same symbols may have the same meanings.

Hereinafter, a liquid crystal compound according to a specific embodiment of the present invention and a liquid crystal composition containing the liquid crystal compound will be described.

One aspect of the present invention provides a liquid crystal compound represented by the following formula (1).

[Chemical Formula 1]

In Formula 1,

In Formula 1,

R ₁ and R ₂ are each independently an alkyl or alkoxy radical having 1 to 15 carbon atoms and wherein at least one CH ₂ group in the radical is independently selected from the group consisting of -C = _{CF 2 O-, -CH = CH-,} -O-, or substituted with -CO-O- or -OC-O-, which can be optionally substituted with one or more hydrogen atom is halogen,

Ring A ₁ is 1,4-cyclohexylene or 1,4-cyclohexenylene,

L ₁ and L ₂ are each independently hydrogen, fluorine, an alkyl radical or an alkoxy radical, and the CH ₂ groups in the radicals may be substituted with one or more halogens.

More specifically, the 1,4-cyclohexenylene is 1,4-cyclohexe-1-ne, or 1,4-cyclohexen- 1,4-cyclohexe-3-ne < / RTI >

More specifically, the liquid crystal compound represented by Formula 1 may be any one of the following Formulas 1-1 to 1-12.

[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

[Formula 1-4]

[Formula 1-5]

[Chemical Formula 1-6]

[Chemical Formula 1-7]

[Chemical Formula 1-8]

[Chemical Formula 1-9]

[Chemical Formula 1-10]

[Formula 1-11]

[Formula 1-12]

.

.

The physical properties of the compounds of Formulas 1-1 to 1-12 were compared with those of existing materials, and the results are shown in Table 1. When the above compound and the conventional substance are compared, it can be seen that the rotational viscosity of the following formula 1 is low while the dielectric anisotropy is similar.

[Formula 1]

According to another embodiment of the present invention, there is provided a liquid crystal composition comprising at least one liquid crystal compound represented by the formula (1).

The liquid crystal composition includes at least one liquid crystal compound represented by the above formula (1). The liquid crystal composition may include at least one liquid crystal compound represented by the formula (1) in an amount of 1% by weight or more based on the total weight of the liquid crystal composition. If the content of the liquid crystal compound represented by the general formula (1) is less than the above range, the effect of improving the response speed may be insignificant. In addition, the liquid crystal composition may include at least one liquid crystal compound represented by the formula (1) in an amount of not more than 60% by weight based on the total weight of the liquid crystal composition. For example, the liquid crystal composition may contain 1 to 60% by weight, 5 to 60% by weight, 10 to 60% by weight, 20 to 60% by weight, 30 to 60% by weight, 1 to 50% by weight, 1 to 40% by weight, 1 to 30% by weight, or 5 to 30% by weight of the liquid crystal compound represented by the above formula (1). When the content of the liquid crystal compound is within the above range, the value of? 1 / K ₃₃ of the liquid crystal composition can be lowered. If the content of the liquid crystal compound represented by the formula (1) is in excess of the above range, the phase transition temperature of the liquid crystal composition may be greatly increased, which may result in a problem that a liquid crystal phase can not be secured in a low temperature region.

The liquid crystal compound of Formula 1 may exhibit a significantly reduced rotational viscosity while maintaining high dielectric anisotropy and refractive index anisotropy. In particular, the liquid crystal compound of formula (1) exhibits a remarkably reduced rotational viscosity as compared with a three-ring liquid crystal compound having negative dielectric anisotropy, and exhibits excellent physical properties. Accordingly, it is expected that a liquid crystal display device of VA mode, PSA mode, PS-VA mode, IPS mode or FFS mode can be provided by using the liquid crystal compound of formula (1).

In one embodiment of the present invention, the liquid crystal composition applicable to the liquid crystal display may further include at least one liquid crystal compound represented by the following formulas (2) to (4) in addition to the liquid crystal compound represented by the formula (1).

(2)

(3)

[Chemical Formula 4]

In the above Chemical Formulas 2 to 4,

R ₁ 'and R _2' are each independently any one of alkyl radicals containing from 1 to 7 carbon atoms, or said at least one of the radicals is H or substituted with halogen or one or more -CH ₂ - is an oxygen atom are not to be connected directly to -O-CO-, or -O-CO-O-, in which R <

R ₃ to R ₆ are each independently an alkyl or alkoxy radical having 1 to 15 carbon atoms, and one or more -CH ₂ - groups in the radicals are independently selected from the group consisting of -C = C -, -CF ₂ O-, -CH = CH-, -O-, -CO-O- or -OC-O-, or one or more hydrogen atoms may be substituted with halogen,

Z ₅ is a single bond, or a group represented by -CH ₂ O-, -OCH ₂ -, -CH ₂ CH ₂ -, -CF ₂ O-, -OCF ₂ -, -CH═CH-, -CF═CF-, -C = C-, -COO-, -OCO-,

Rings A and B are each independently 1,4-cyclohexylene, or 1,4-phenylene,

Rings C, D, and E are each independently any one of the following structures:

The rings F, G and I are each independently 1,4-cyclohexylene, 1,4-phenylene or 1,4-phenylene in which one fluorine is substituted,

(F) is hydrogen or F,

e and f are not are each independently an integer of 0 or 1, with the proviso that e is 1 and f is 0, and Z ₅ are united unity when ring C is phenyl,

g and h are each independently an integer of 0 or 1, and g + h is an integer of 1 or more.

The liquid crystal compound of Formula 2 is a low viscosity liquid crystal compound that affects the response time of the display. When the rings A and B are all 1,4-cyclohexylene, R ₁ and R ₂ are all alkyl or R ₁ , R < ₂ > is alkenyl, it is advantageous to improve the response time by lowering the rotational viscosity while keeping the transparent point constant. The liquid crystal compound of Formula 2 may be included in an amount of 5 to 50% by weight based on the total weight of the liquid crystal composition. If it is less than 5% by weight, securing the rotational viscosity is difficult, and if it is more than 50% by weight, it is difficult to secure a transparent point, and the operating temperature of the display is greatly lowered. More specifically, the liquid crystal compound of Formula 2 may be contained in an amount of 15 to 40% by weight based on the total weight of the liquid crystal composition.

Representative materials of the compound represented by Chemical Formula 2 may be represented by Chemical Formulas 2-1 and 2-2, wherein R ₁ 'and R ₂ ' are as defined in Chemical Formula 2, and R ₁₁ is hydrogen, -CH = CH-, -CH = CH-, -NH-, -NH- or -NR < _{2 &} gt ;, wherein at least one of the radicals of the radicals is substituted with halogen or one or more- -O-, -CO-O-, -O-CO- or -O-CO-O-.

[Formula 2-1]

[Formula 2-2]

The liquid crystal compound represented by Formula 3 is a compound having an absolute value of dielectric constant of greater than 1, and exhibits substantial display characteristics by increasing dielectric anisotropy. The liquid crystal compound of Formula 3 may be contained in an amount of 20 to 70% by weight based on the total weight of the liquid crystal composition. When less than 20% by weight is used, the dielectric anisotropy is too low and the driving voltage of the display becomes too high. If it exceeds 70% by weight, the viscosity increases or the transparent point can not be secured. It is hard to satisfy. The compounds represented by Formula 3 may include compounds represented by Formulas 3-1 to 3-7. In the formulas, R ₃ and R ₄ have the same definitions as in Formula 3, and (F) It can be replaced with hydrogen or fluorine.

[Formula 3-1]

[Formula 3-2]

[Formula 3-3]

[Chemical Formula 3-4]

[Formula 3-5]

[Chemical Formula 3-6]

[Chemical Formula 3-7]

.

.

In particular, according to one embodiment of the present invention, the compound represented by Formula 3-2 or Formula 3-5 promotes the reaction of the polymerizable compound represented by Formula 7 in the PSA mode to increase the change in the tilt angle, Can be improved.

The liquid crystal compound represented by Formula 4 is a substance having a transparent point of 80 degrees or more and is an important material for determining the operating temperature in a display, and may be used in an amount of 5 to 60% by weight based on the total weight of the liquid crystal composition. If it is used in an amount of less than 5% by weight, it is difficult to secure a transparent point and a refractive index. If it exceeds 60% by weight, the viscosity increases and the response time of the display becomes too slow. Representative materials of the compound represented by the formula (4) may be represented by the following formulas (4-1) to (4-3), R ₅ and R ₆ are the same as defined in the formula (4) ≪ / RTI >

[Formula 4-1]

[Formula 4-2]

[Formula 4-3]

.

.

In the present invention, the liquid crystal composition may further include at least one compound represented by the following general formula (5) or (6). The compound of the formula (5) is a substance which improves the thermal stability of the liquid crystal composition as an antioxidant, and may be added in an amount of 0.01 to 0.05% by weight based on the total weight of the liquid crystal composition. The compound represented by the formula (6) may be added as an ultraviolet stabilizer in an amount of 0.01 to 0.1% by weight based on the total weight of the liquid crystal composition.

[Chemical Formula 5]

[Chemical Formula 6]

In the above formulas (5) and (6)

R ₇ is alkyl having 1 to 12 carbon atoms,

R ₈ and R ₉ are each independently hydrogen, oxygen, or alkyl having 1 to 12 carbon atoms,

Ring J is cyclohexyl or phenyl,

i is an integer of 0 or 1,

k is an integer of 1 to 12;

According to an embodiment of the present invention, when the liquid crystal compound represented by the general formula (1) and a reactive compound are used together, the pretilt angle can be more controlled.

The reactive compound is preferably a polymerizable compound represented by the following formula (7).

(7)

P ₁ -Sp ₁ - (K ₁ -Y ₁ ) _a - (K ₂ -Y ₂ ) _b - (K ₃ -Y ₃ ) _c -Sp ₂ -P ₂

P ₁ and P ₂ are each independently a polymerizable functional group, a C 1 -C 9 alkyl, alkenyl having 2 to 9, H, F, Cl, or means the CN, and at least one of P ₁ and P ₂ are polymerized Functional group,

Sp ₁ and Sp ₂ are each independently a single bond or a radical of any of the alkyl having 1 to 15 carbon atoms, or at least one hydrogen atom of the radical is substituted with halogen or one or more -CH ₂ - -O-, -O-CO-, or -O-CO-O-, with the proviso that R &

Y ₁ to Y ₃ are each independently _{-CH 2 CH 2 -, -CH =} CH-, -CH 2 O-, -OCH 2 -, -C = C-, -CH 2 CF 2 -, -CHFCHF-, -CF ₂ CH ₂ -, -CH ₂ CHF-, -CHFCH ₂ -, -C ₂ F ₄ -, -O-, -COO-, -OCO-, -CF ₂ O-, -OCF ₂ - ego,

K ₁ to K ₃ each independently represent a cycloalkyl, an aromatic ring or a heterocyclic ring composed of 5 to 7 carbons, and hydrogen in the ring structure may be substituted with fluorine or an alkyl or alkoxy radical having 1 to 15 carbon atoms, Is an aromatic ring or a heterocyclic ring, and hydrogen in the ring structure may be substituted with fluorine or an alkoxy radical having 1 to 15 carbon atoms.

a, b and c are integers of 0 to 2, and a + b + c is 1 to 3.

In the embodiment of the present invention, considering the ease of synthesis, Sp ₁ and Sp ₂ represent a single bond, and the ultraviolet ray reactor P ₁ and P ₂ can use the following structures:

.

.

According to an embodiment of the present invention, the polymerizable compound may be represented by any one of the following formulas (7-1) to (7-9), and the liquid crystal composition may include at least one polymerizable compound.

[Formula 7-1]

[Formula 7-2]

[Formula 7-3]

[Chemical Formula 7-4]

[Formula 7-5]

[Formula 7-6]

[Formula 7-7]

[Formula 7-8]

[Formula 7-9]

In the above formulas,

P ₁ and P ₂ are the same as defined in Formula 7, Y ₄ and Y ₅ are each independently -CH ₂ CH ₂ -, -CH═CH-, -CH ₂ O-, -OCH ₂ -, - _{C = C-, -CH 2 CF 2} -, -CHFCHF-, -CF 2 CH 2 -, -CH 2 CHF-, -CHFCH 2 -, -C 2 F 4 -, -O-, -COO-, - _{OCO-, -CF 2 O-, -OCF 2} - or a single bond, m1 and m2 are each independently are an integer from 1 to 8 from each other, r1 and r2 are each independently an integer of 0 or 1, R _a, and R _b are each independently of the other hydrogen or -CH ₃ , ring K is heteroarylene having 5 carbon atoms, and hydrogen in the ring may be substituted with fluorine or an alkyl or alkoxy radical having 1 to 15 carbon atoms.

For example, the cycloalkylene may be 1,3-cyclopentyl, the heteroarylene may include oxygen or S as a heteroatom, and may be, for example, 1 , 1,3-furanyl, or 1,3-thiophenyl.

In addition, P ₁ and P ₂ may be acrylate or methacrylate.

In one embodiment of the present invention, the polymerizable compound represented by Formula 7 may include 0.01 to 0.2% by weight based on the total weight of the liquid crystal composition. If it is used in an amount exceeding 0.2% by weight, the increase of the amount of the residual polymerizable compound may affect display characteristics and reliability.

In the specific structures of formulas (7-1) to (7-9), the following formulas (7-2-1) to (7-9-4) may be used, wherein P ₁ and P ₂ may be acrylate or methacrylate. In this case, it is more suitable for the PSA mode. According to an embodiment of the present invention, in the liquid crystal composition containing the polymerizable compound, when the P ₁ and P ₂ are all methacrylate, the change of the tilt angle is particularly large. Specifically, 1 to 7 to 8, the change of the inclination angle is large.

The liquid crystal composition used in the PSA mode contains a polymerizable compound. Basically, when the polymerizable compound is mixed with the liquid crystal, it is required to maintain a stable state at a low temperature, and photopolymerization should be effectively performed by ultraviolet rays.

The polymerizable compound is also preferably polymerized by photopolymerization, for example UV irradiation, in the presence of a suitable initiator. Suitable conditions for polymerization and suitable types and amounts of initiators are known to those skilled in the art and are described in the literature. For example, commercially available photoinitiators Irgacure 651 (registered trademark), Irgacure 184 or Darocure 1173 (registered trademark, Ciba Geigy AG) are suitable for free radical polymerization The polymerizable compound may contain 0.1 to 5% by weight, and more specifically 1 to 3% by weight, of at least one photoinitiator. When the polymerizable compound is contained in such an amount, the photoinitiator And a larger amount of the radicals than the above amount may adversely affect the display characteristics such as a residual image due to a residual photoinitiator.

In one embodiment of the present invention, the liquid crystal composition may include various combinations of one or more compounds represented by the formula (1), one or more compounds represented by the formula (2) and the compound represented by the formula (7).

For example, the liquid crystal composition may include a compound represented by Formula 1, a compound represented by Formula 2, and a compound represented by Formula 4, or may include a compound represented by Formula 1 and a compound represented by Formula 3 . Those containing the compound is the liquid crystal composition represented by the compound represented by the formula (1) compound and formula (4) represented by the formula (2), lowering the rotation viscosity, so to increase the clearing point, the refractive index and K ₃₃ values γ1 / K ₃₃ value Which may be more advantageous. The compound represented by Formula 1 may include at least one compound, and the compound represented by Formula 3 may include at least one compound. When the liquid crystal composition contains two or more compounds represented by the formula (1) and two or more compounds represented by the formula (3), when one of the compounds represented by the formula (3) is a formula (3-1) The viscosity can be lowered, which can be more advantageous in lowering the? 1 / K ₃₃ value. When the liquid crystal composition contains two or more compounds represented by the formula (1), the low temperature stability can be improved.

The liquid crystal composition comprising the compound represented by the formula (1), the compound represented by the formula (2) and the compound represented by the formula (4), or the compound represented by the formula (1) and the compound represented by the formula (3) And may further comprise at least one compound selected from the compounds represented by the general formulas (1-1) to (1-2).

The present invention provides a liquid crystal display comprising the liquid crystal composition.

1 is a cross-sectional view of a liquid crystal display according to an embodiment of the present invention. 1, a liquid crystal display according to an embodiment of the present invention includes a first substrate SUB1, a second substrate SUB2 opposed to the first substrate SUB1, And a liquid crystal layer LC formed between the second substrates SUB2.

The first substrate SUB1 includes a wiring portion provided on the first base substrate BS1, a transistor TR connected to the wiring portion, a pixel electrode PE connected to the transistor TR, PE and a common electrode CE spaced apart from the PE.

The first base substrate BS1 has a substantially rectangular shape and is made of a transparent insulating material. The wiring portion includes a gate line GL and a data line GL.

A gate insulating film GI is provided on the first base substrate BS1 on which the gate lines GL are formed. The gate insulating layer GI may be made of an insulating material, for example, silicon nitride or silicon oxide.

The data line GL is provided extending in a second direction D2 intersecting the first direction D1 with the gate line GL and the gate insulating film GI interposed therebetween.

The transistor TR is connected to the gate line GL and the data line GL. The transistor TR includes a gate electrode GE, a semiconductor pattern SM, a source electrode SE, and a drain electrode DE.

The transistor TR includes a gate electrode GE, a semiconductor pattern SM, a source electrode SE, and a drain electrode DE.

The gate electrode GE protrudes from the gate line GL or is provided on a partial area of the gate line GL.

An interlayer film (IL) is provided on the source electrode (SE) and the drain electrode (DE). A protective film PSV is provided on the interlayer film IL and a contact hole CH exposing a part of the top surface of the drain electrode DE is provided in the interlayer film IL and the protective film PSV.

The second substrate SUB2 is provided opposite to the first substrate SUB1. The second substrate SUB2 may include a second base substrate BS2, a color filter CF, and a black matrix BM.

The liquid crystal layer LC includes the liquid crystal composition according to one embodiment of the present invention described above.

More specifically, the liquid crystal display may include a liquid crystal composition containing at least one compound represented by the formula (1) or further comprising a compound represented by the formula (2) to (4) ≪ / RTI > compounds. For example, the liquid crystal display may comprise a liquid crystal composition comprising at least one compound represented by the formula (1), at least one of the compounds represented by the formulas (2) to (4), and various combinations of the compound represented by the formula (7).

The liquid crystal display may be a VA mode, a PSA mode, a PS-VA mode, an IPS mode, or an FFS mode, but is not limited thereto.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other objects, features and advantages of the present invention will be more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which: FIG. However, this is provided as an example of the invention, and the scope of the invention is not limited thereto in any sense.

<Examples>

The synthesis method of each step of the liquid crystal compound represented by the formula (1) is as follows.

Production Example 1. Synthesis of liquid crystal compound of formula 1-1

4-Ethoxy-2,3-difluoro-4 "-methyl-1 ', 2', 3 ', 6'-tetrahydro- - terphenyl is prepared as follows.

[Step 1]

30.0 g (0.126 mol) of Compound 2 was dissolved in anhydrous tetrahydrofuran under a nitrogen stream. After cooling to -70 ° C using an ice bath, 75.9 ml of 2.5M n-butyllithium was added dropwise. After stirring for 1 hour, 16.5 g (0.105 mol) of Compound 1 was dissolved in anhydrous tetrahydrofuran and added dropwise. After stirring for 1 hour, the temperature was raised to room temperature and stirred for 2 hours. The reaction solution was diluted with water and diethyl ether, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulfate. eluting with a 2: 1 solution of n-heptane: ethyl acetate on a silica gel column to give compound 3 (36.2 g, 60% yield ) .

[Second Step]

27.8 g (0.088 mol) of Compound 3 was dissolved in a toluene: ethylene diol = 4: 1 solution under a nitrogen stream, and then 1.7 g (0.009 mol) of paratoluenesulfonic acid was added. The temperature was raised to 110 DEG C and refluxed for 4 hours. After cooling, the reaction solution was diluted with water and diethyl ether, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulfate. eluting with a 5: 1 solution of n-heptane: ethyl acetate on a silica gel column to give compound 4 (23.8 g, 91% yield ) .

[Third Step]

25.0 g (0.084 mol) of Compound 4 was dissolved in ethanol, and then 2.5 g of 10 wt% Pd / C was added. The mixture was stirred at room temperature for 6 hours under a hydrogen gas pressure of 6 atm. After filtration of 10 wt% Pd / C, the solvent was removed. Compound 5 (24.6 g, 98% yield ) was obtained by eluting on a silica gel column with a 5: 1 solution of n-heptane: ethyl acetate.

[Step 4]

24.6 g (0.083 mol) of compound 5 was dissolved in toluene under a nitrogen stream, and then 40.4 ml of formic acid was added. After stirring at room temperature for 6 hours, the reaction solution was diluted with water and diethyl ether, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulfate. eluting with a 5: 1 solution of n-heptane: ethyl acetate on a silica gel column gave compound 6 (17.1 g, 82% yield).

[Step 5]

Under a stream of nitrogen, 16.1 g (0.095 mol) of compound 7 was dissolved in anhydrous tetrahydrofuran. After cooling to -70 ° C using an ice bath, 40.9 ml of 2.5M n-butyllithium was added dropwise. After stirring for 1 hour, 20.0 g (0.078 mol) of Compound 6 was dissolved in anhydrous tetrahydrofuran and added dropwise. After stirring for 1 hour, the temperature was raised to room temperature and stirred for 2 hours. The reaction solution was diluted with water and ethyl acetate, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulfate. Eluting with a 2: 1 solution of N-heptane: ethyl acetate on a silica gel column gave compound 8 (14.0 g, 64% yield).

[Step 6]

19.1 g (0.055 mol) of Compound 8 was dissolved in a toluene solution under a nitrogen stream, and then 1.0 g (0.005 mol) of paratoluenesulfonic acid was added. The temperature was raised to 110 DEG C and refluxed for 4 hours. After cooling, the reaction solution was diluted with water and diethyl ether, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulfate. eluting with a 5: 1 solution of n-heptane: ethyl acetate on a silica gel column to obtain compound 9 ( formula 1-1) (14.4 g, 80% yield).

The physical property of this compound was Cr 94.6 N 116.2 I.

MS (EI) m / z = 129, 156, 184, 328 (M &lt; + &gt;).

Production Example 2. Synthesis of liquid crystal compound of formula 1-2

A process for producing a liquid crystal compound of 1-ethoxy-2,3-difluoro-4- (4- (p-tolyl) cyclohexyl) benzene represented by the formula 1-2 is as follows.

[Step 1]

17.5 g (0.053 mol) of Compound 9 was dissolved in ethanol and 1.7 g of 10 wt% Pd / C was added. The mixture was stirred at room temperature for 6 hours under a hydrogen gas pressure of 6 atm. 10 wt% Pd / C was filtered off and the solvent was removed. A 2: 3 ratio of isomeric compound 10 (16.7 g, 95% yield) was obtained by eluting on a silica gel column with a 5: 1 solution of n-heptane: ethyl acetate.

[Second Step]

17.0 g (0.051 mol) of Compound 10 was dissolved in dichoromethane under a nitrogen stream, and then 3.4 g (0.025 mol) of aluminum chloride was added. Stir at room temperature for 6 hours. The reaction solution was diluted with water and toluene, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulfate. eluting with a 5: 1 solution of n-heptane: ethyl acetate on a silica gel column to obtain compound 11 ( formula 1-2) (15.3 g, 90% yield).

The physical property of this compound was Cr 95.0 N 118.2 I.

MS (EI) m / z = 105, 172, 238, 330 (M &lt; + &gt;).

Production Example 3. Synthesis of Liquid Crystal Compound of Formula 1-3

1 ': 4', 1 '', 2 ', 3', 6'-tetrahydro- -Terphenyl was obtained in the same manner as in Production Example 1, except that 4-ethoxy-2,3-difluoro-1-bromobenzene (2) 3-difluoro-1-bromobenzene was used instead of 3-Difluoro-1-bromobenzene.

The physical property of this compound was Cr 99.5 N 103.5 I.

MS (EI) m / z = 129, 156, 212, 356 (M &lt; + &gt;).

Production Example 4. Synthesis of Liquid Crystal Compound of Formula 1-4

The liquid crystal compound of 1-butoxy-2,3-difluoro-4- (4- (p-tolyl) cyclohexyl) benzene of formula 1-4 is converted to 4- (1) except that 4-butoxy-2,3-difluoro-1-bromobenzene was used in place of 2-ethoxy-2,3-difluoro- Can be produced in the same manner as in Production Example 2 of

The physical property of this compound was Cr 68.5 N 100.6 I.

MS (EI) m / z = 131, 172, 210, 358 (M &lt; + &gt;).

Production Example 5. Synthesis of liquid crystal compound of formula (1-5)

4 ', 4', 4'-ethyl-1 ', 2', 3 ', 6'-tetrahydro- -Terphenyl was obtained in the same manner as in Production Example 1, using 1-bromo-4-ethylbenzene instead of 1-bromo-4-methylbenzene (7) Can be prepared according to the same method as Preparation Example 1 mentioned in Preparation Example 1.

The physical property of this compound was Cr 67.3 N 91.5 I.

MS (EI) m / z = 129, 156, 184, 342 (M &lt; + &gt;).

Production Example 6. Synthesis of liquid crystal compound of formula 1-6

The liquid crystal compound of 1-ethoxy-4- (4- (4-ethylphenyl) cyclohexyl) -2,3-difluorobenzene of the formula 1-6 is reacted with 1- Bromo-4-ethylbenzene in place of bromo-4-methylbenzene (7) in the same manner as in Production Example 1-2.

The physical property of this compound was Cr 66.5 N 96.0 I.

MS (EI) m / z = 117, 186, 238, 344 (M &lt; + &gt;).

Production Example 7. Synthesis of Liquid Crystal Compound of Formula 1-7

4 ', 1' ': 4' '- ethyl-1', 2 ', 3', 6'-tetrahydro- -Terphenyl was obtained in the same manner as in Production Example 1, except that 4-ethoxy-2,3-difluoro-1-bromobenzene (2) Bromo-4-ethylbenzene instead of 1-bromo-4-methylbenzene (7) in the fifth step using 3-difluoro-1- Can be prepared according to the production method mentioned in Example 1.

The physical property of this compound was Cr 99.2 N 101.1 I.

MS (EI) m / z = 129, 156, 212, 370 (M &lt; + &gt;).

Production Example 8. Synthesis of liquid crystal compound of formula 1-8

The liquid crystal compound of 1-butoxy-4- (4- (4-ethylphenyl) cyclohexyl) -2,3-difluorobenzene of the formula 1-8 is obtained in the first step of Production Example 1 Butoxy-2,3-difluoro-1-bromobenzene was used in the place of 4-ethoxy-2,3-difluoro-1-bromobenzene (2) Bromo-4-ethylbenzene in place of bromo-4-methylbenzene (7) in the same manner as in Production Example 1-2.

The physical property of this compound was Cr 77.1 N 82.3 I.

MS (EI) m / z = 117, 186, 316, 372 (M &lt; + &gt;).

Production Example 9. Synthesis of liquid crystal compound of formula 1-9

4-Ethyl-4'-propyl-1 ', 2', 3 ', 6'-tetrahydro-l, -Terphenyl was obtained in the same manner as in Production Example 1-1 using the 1-bromo-4-propylbenzene instead of 1-bromo-4-methylbenzene (7) Can be prepared according to the production method mentioned in Example 1.

The physical property of this compound was Cr 86.9 N 109.2 I.

MS (EI) m / z = 129, 156, 184, 356 (M &lt; + &gt;).

Production Example 10. Synthesis of liquid crystal compound of formula 1-10

The liquid crystal compound of 1-ethoxy-4- (4- (4-propylphenyl) cyclohexyl) -2,3-difluorobenzene of the formula 1-10 is obtained in the fifth step of Production Example 1-1 Bromo-4-propylbenzene instead of 1-bromo-4-methylbenzene (7) according to the preparation method described in Preparation Example 1-2.

The physical property of this compound was Cr 81.4 N 117.1 I.

MS (EI) m / z = 117, 200, 238, 358 (M &lt; + &gt;).

Production Example 11. Synthesis of Liquid Crystal Compound of Formula 1-11

4'-propyl-1 ', 2', 3 ', 6'-tetrahydro-1,1': 4 ', 1 " -Terphenyl was obtained in the same manner as in Production Example 1, except that 4-ethoxy-2,3-difluoro-1-bromobenzene (2) Bromo-4-propylbenzene instead of 1-bromo-4-methylbenzene (7) in the fifth step using 3-difluoro-1- Can be prepared according to the production method mentioned in Example 1.

The physical property of this compound was Cr 73.1 N 102.9 I.

MS (EI) m / z = 129, 156, 212, 384 (M &lt; + &gt;).

Production Example 12. Synthesis of Liquid Crystal Compound of Formula 1-12

The liquid crystal compound of 1-butoxy-4- (4- (4-propylphenyl) cyclohexyl) -2,3-difluorobenzene of the formula 1-12 is obtained in the first step of Production Example 1 Butoxy-2,3-difluoro-1-bromobenzene was used in the place of 4-ethoxy-2,3-difluoro-1-bromobenzene (2) Bromo-4-propylbenzene in place of bromo-4-methylbenzene (7) according to the preparation method described in Preparation Example 1-2.

The physical property of this compound was Cr 56.3 I.

MS (EI) m / z = 117, 200, 330, 386 (M &lt; + &gt;).

Experimental Example 1. Evaluation of Physical Properties of Liquid Crystal Compound

Specifically, the physical properties of the liquid crystal compound are defined as extrapolated values obtained by substituting the measurement value of the sample prepared by mixing 10% by weight of the liquid crystal compound and 90% by weight of the mother liquid crystal to be measured with the formula 2 below. At this time, the composition of the mother liquid crystal is shown in Table 2.

[Formula 2]

(Measured value of the sample) - (measured value of the liquid crystal)} / (weight% of the liquid crystal compound) x 100]

(1) Refractive index anisotropy of liquid crystal compound [n]

Was measured with an Abbe refractometer equipped with a polarizing plate on an eyepiece using light having a wavelength of 589 nm at 20 ° C. After rubbing the surface of the main prism in one direction, the sample was dropped onto the main prism. Thereafter, the refractive index (n∥) when the direction of the polarized light was parallel to the rubbing direction and the refractive index (n⊥) when the polarizing direction was perpendicular to the rubbing direction were measured. Then, the refractive index anisotropy (? N) was measured by substituting the refractive index value into the equation (3).

[Formula 3]

? N = n? - n?

(2) Dielectric constant anisotropy of liquid crystal compound [DELTA epsilon]

 The values of ε∥ and ε⊥ measured as described below were calculated by substituting in Equation 4.

[Formula 4]

△ = ε∥ - ε⊥

(1) Measurement of dielectric constant??: A vertical alignment agent was applied to the surface of the two glass substrates on which the ITO pattern was formed to form a vertical alignment film. Subsequently, the spacers were coated on one of the two glass substrates so that the vertical alignment films faced each other and the interval (cell gap) between the two glass substrates was 4 占 퐉, and then the two glass substrates were bonded together. The sample was then injected into the device and sealed with an ultraviolet curing adhesive. Thereafter, it was used in 4294A equipment manufactured by Agilent, and the dielectric constant? ∥ was measured at 20 ° C of the device.

(2) Measurement of dielectric constant??: A horizontal alignment agent was applied to the surface of the two glass substrates on which the ITO pattern was formed to form a horizontal alignment film. Subsequently, the spacers were coated on one of the two glass substrates so that the horizontal alignment films faced each other and the interval (cell gap) between the two glass substrates was 4 占 퐉, and then the two glass substrates were bonded together. Then, a sample was injected into the device, and the sample was sealed with an adhesive that hardened with ultraviolet rays. Thereafter, the device was used in a 4294A instrument manufactured by Agilent, and the dielectric constant?? Of the device was measured at 20 ° C.

(3) Rotational viscosity [? ₁ ] of the liquid crystal compound [

The device was fabricated in the following manner. A vertical alignment agent was applied to the surface of the two glass substrates on which the ITO pattern was formed to form a vertical alignment film. Subsequently, the spacers were coated on one of the two glass substrates so that the vertical alignment films faced each other and the interval (cell gap) between the two glass substrates was 50 占 퐉, and then the two glass substrates were bonded together. Then, a sample was injected into the device, and the sample was sealed with an adhesive that hardened with ultraviolet rays. Thereafter, using a Model 6254 instrument manufactured by Toyo Corp. equipped with a temperature controller (Model SU-241) manufactured by ESPEC Corp., the rotational viscosity of the device was measured at 20 ° C.

(4) Elastic modulus of liquid crystal compound [K ₃₃ ]

EC-1 (Toyo Corp.) Measure the CV curve with a 1kHz sine wave while sweeping the measuring instrument from 0V to 20V in 0.1V step at 20 ℃ in 10Hz short wave form. The cell gap and the dielectric anisotropy values are given in Equation 5, and then the fitting method according to the liquid crystal is selected to calculate K ₁₁ and K ₃₃ .

        [Formula 5]

C ₀ : Initial Capacitance, V _th : Threshold Voltage, r : Normalized Dielectric Anisotropy,

k: Ratio of Elastic Constant, θ: The surface LC director orientation in a voltage-on state

θ _m : Tilt angle at d / 2

In general, the elastic modulus of the liquid crystal can be divided into splay (K ₁₁ ), twist (K ₂₂ ), and bend (K ₃₃ ) elastic modulus. The simplest method for measuring these elastic moduli is to fabricate a horizontal alignment cell and a vertical alignment cell to determine the K ₁₁ and K ₂₂ from the Fredericks transition by the capacitance value by applying vertical and horizontal magnetic fields to the horizontal alignment cell . By applying a magnetic field to the vertically aligned Cell, K ₃₃ can be determined in the same way. However, such a method requires a strong magnetic field. On the other hand, when the electric field is used, since the thickness of the liquid crystal sample is thin, the elastic modulus can be obtained through the motion of the liquid crystal molecules even at a small voltage.

(5) Transparent point of liquid crystal compound (Tni)

 A liquid crystal compound was placed on a hot plate of a melting point measuring apparatus equipped with a polarizing microscope and heated at a rate of 3 ° C / minute to measure the temperature when a part of the liquid crystal compound changed into a liquid crystalline phase or an isotropic liquid crystal phase.

Experimental Example 2. Evaluation of Physical Properties of Liquid Crystal Composition Comprising the Invention Material

The physical properties of the liquid crystal composition are the same as those of the liquid crystal compound of the invention. In the liquid crystal composition for PSA containing the polymerizable compound as shown in formula (7), the liquid crystal composition was injected into the evaluation cell, and the pretilt angles before and after the ultraviolet irradiation were measured. The method of measuring the angle of incidence, evaluation cell production method, and ultraviolet irradiation method are as follows.

 (1) Pre-warping angle? P

For the measurement of the pretilt angle, liquid crystals were injected into the evaluation cell of item (2) and measured by a modified crystal rotation method. The measurement method was measured by using the refractive index anisotropy change of the cell in which the liquid crystal was injected, and the PAMS measuring device of Cecco Optoelectronics Technology Co., Ltd. was used.

(2) Evaluation cell fabrication

The upper and lower plates of the cell made of glass are ITO electrodes having a width of 10 mm and capable of being connected to electric wires, and a vertical alignment agent is cured on the ITO electrodes. At this time, the vertical alignment agent of the upper and lower plates was rubbed weakly by rotating the roll (500 rpm) coated with the rayon fibers, and the gap between the upper and lower plates was 4 um.

(3) Ultraviolet irradiation method

The liquid crystal mixture to which the polymerizable compound was added was injected into the evaluation cell, and ultraviolet rays were irradiated while an alternating current of 10 V was applied. The ultraviolet ray used a light source having a major wavelength band of 365 nm when irradiated, and 10 J was irradiated in the present invention unless otherwise specified.

In the examples and comparative examples of the liquid crystal composition comprising the inventive material, the detailed materials are symbolized as shown in Table 3.

Comparative Example 1, Comparative Example 2, Examples 1 to 10

The liquid crystal compositions of Comparative Example 1, Comparative Example 2, and Examples 1 to 10 were prepared and their physical properties were measured. The composition of the liquid crystal composition and the results of the physical property values thereof are shown in Tables 4 and 5.

Examples 1 to 10 which are the liquid crystal compositions of the present invention have a small rotational viscosity (? 1), a large elastic modulus (K ₃₃ ) and a? 1 / K ₃₃ of 8.0 or less. It is confirmed that this value is smaller than? 1 / K ₃₃ of Comparative Examples 1 and 2, and in particular,? 1 / K ₃₃ is more effectively reduced in Examples 8 and 10 using BB-3.V. In the case of using the AF-3.O2 compound of the formula 3-2 at 5 wt% or more, it was confirmed that? 1 / K ₃₃ was smaller than that of Example 9 which was not used.

In view of the above, the liquid crystal composition of the present invention has a sufficiently low rotational viscosity (? 1) and a high elastic modulus (K ₃₃ ) without lowering the refractive index anisotropy (n) and the nematic phase- isotropic liquid crystal phase transition temperature , And the absolute value has a negative dielectric constant anisotropy (DELTA epsilon), it has been confirmed that liquid crystal display devices such as VA and PSA modes using the same have excellent display quality and a high response speed.

Examples 11 to 22

The liquid crystal compositions of Examples 11 to 22 were prepared, vacuum poured into the evaluation cell, and the pretilt angles before and after irradiation with ultraviolet light were measured. The composition of the liquid crystal composition and the results of the pretilt angles were as shown in Tables 6 and 7. The polymerizable compounds used were the following four kinds, and evaluation was made by using 0.1 wt% of Irgacure 651 as a polymerization initiator in the composition.

In the liquid crystal composition examples containing the polymerizable compound, it can be seen that the pretilt angle after polymerization is reduced by ultraviolet irradiation. In particular, in Example 12, Example 15, Example 18, Example 20 where the polymerizable group is a methacrylic series and AA-M in which the present invention is mixed, it is found that the reactivity is good since the inclination angle is less than 80 degrees after ultraviolet ray polymerization . Examples using an acrylate-based polymerizable compound such as AA-H and AAC1-H also show an effective change in the tilt angle. It can be seen that the largest change in the inclination angle was observed in the case of Examples 21 and 22 in which the compound of Formula 1 and the compound of Formula 7-9-3 represented by ATE-M were mixed.

It can be seen that the compositions of Examples 11 to 16 using 5 wt% or more of the compound represented by the formula (1) and AF-3.O2 (3-2) in the composition are more effective than those of Examples 17 to 19.

The liquid crystal composition of the present invention is a liquid crystal composition having a sufficiently small rotational viscosity (? 1), a large elastic modulus (K ₃₃ ), and a low viscosity (?) Without lowering the refractive index anisotropy (n) and the nematic phase-isotropic liquid crystal phase transition temperature It has been confirmed that liquid crystal display devices such as VA, PSA mode and PS-VA mode using the same have a good display quality and a high response speed because they have a negative dielectric constant anisotropy (DELTA epsilon) and have a sufficiently suitable pretilt angle.

Claims (20)

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

In Formula 1,
R ₁ and R ₂ are each independently an alkyl or alkoxy radical having 1 to 15 carbon atoms and wherein at least one -CH ₂ - group in the radical is independently selected from the group consisting of -C = C- , -CF ₂ O-, -CH = CH-, -O-, -CO-O- or -OC-O-, or one or more hydrogen atoms may be substituted with halogen,
Ring A ₁ is 1,4-cyclohexylene or 1,4-cyclohexenylene,
L ₁ and L ₂ are each independently hydrogen, fluorine, an alkyl radical or an alkoxy radical, and the -CH ₂ - groups in the radicals may be substituted with one or more halogens. The method of claim 1,
Wherein the compound represented by the formula (1) is any one of the following formulas (1-1) to (1-12):
[Formula 1-1]

[Formula 1-2]

[Formula 1-3]

[Formula 1-4]

[Formula 1-5]

[Chemical Formula 1-6]

[Chemical Formula 1-7]

[Chemical Formula 1-8]

[Chemical Formula 1-9]

[Chemical Formula 1-10]

[Formula 1-11]

[Formula 1-12]

. 1. A liquid crystal composition comprising a compound represented by the following Formula 1:
[Chemical Formula 1]

In Formula 1,
R ₁ and R ₂ are each independently an alkyl or alkoxy radical having 1 to 15 carbon atoms and wherein at least one -CH ₂ - group in the radical is independently selected from the group consisting of -C = C- , -CF ₂ O-, -CH = CH-, -O-, -CO-O- or -OC-O-, or one or more hydrogen atoms may be substituted with halogen,
Ring A ₁ is 1,4-cyclohexylene or 1,4-cyclohexenylene,
L ₁ and L ₂ are each independently hydrogen, fluorine, an alkyl radical or an alkoxy radical, and the -CH ₂ - groups in the radicals may be substituted with one or more halogens. The method of claim 3,
A liquid crystal composition comprising two or more compounds represented by Formula (1). The method of claim 3,
A liquid crystal composition further comprising at least one compound represented by the following general formulas (2) to (4):
(2)

(3)

[Chemical Formula 4]

In the above Chemical Formulas 2 to 4,
R ₁ 'and R ₂ ' each independently represent a radical of any one of alkyl having 1 to 7 carbon atoms, or one or more hydrogen atoms of the radical are substituted with halogen or one or more -CH ₂ - -O-CO-, or -O-CO-O-, in which R &lt;
R ₃ to R ₆ are each independently an alkyl or alkoxy radical having 1 to 15 carbon atoms, and one or more -CH ₂ - groups in the radicals are independently selected from the group consisting of -C = C -, -CF ₂ O-, -CH = CH-, -O-, -CO-O- or -OC-O, or at least one hydrogen atom may be substituted with halogen,
Z ₅ is a single bond, or a group represented by -CH ₂ O-, -OCH ₂ -, -CH ₂ CH ₂ -, -CF ₂ O-, -OCF ₂ -, -CH═CH-, -CF═CF-, -C = C-, -COO-, -OCO-,
Rings A and B are each independently 1,4-cyclohexylene, or 1,4-phenylene,
Rings C, D, and E are each independently any one of the following structures:

The rings F, G and I are each independently 1,4-cyclohexylene, 1,4-phenylene or 1,4-phenylene in which one fluorine is substituted,
(F) is hydrogen or F,
e and f are not are each independently an integer of 0 or 1, with the proviso that e is 1 and f is 0, and Z ₅ are united unity when ring C is phenyl,
g and h are each independently an integer of 0 or 1, and g + h is an integer of 1 or more. 6. The method of claim 5,
Wherein the compound represented by Formula 2 comprises at least one compound represented by Formula 2-1 or 2-2:
[Formula 2-1]

[Formula 2-2]

In the above formula
R ₁ 'and R ₂ ' are the same as defined in Formula 1,
R ₁₁ is a radical selected from the group consisting of hydrogen, alkyl having 1 to 7 carbon atoms, or a group in which at least one hydrogen atom of the radical is substituted with halogen or one or more -CH ₂ - -CH-CH-, -O-, -CO-O-, -O-CO- or -O-CO-O-. 6. The method of claim 5,
Wherein the compound represented by Formula 3 comprises at least one compound represented by Formula 3-1 to Formula 3-7:
[Formula 3-1]

[Formula 3-2]

[Formula 3-3]

[Chemical Formula 3-4]

[Formula 3-5]

[Chemical Formula 3-6]

[Chemical Formula 3-7]

In the above formulas,
R ₃ and R ₄ are the same as defined in Formula 3,
(F) means that it can be substituted with hydrogen or fluorine. 6. The method of claim 5,
Wherein the compound represented by Formula 4 comprises at least one compound represented by any one of the following Formulas 4-1 to 4-3:
[Formula 4-1]

[Formula 4-2]

[Formula 4-3]

In the above formulas,
R ₅ and R ₆ are the same as defined in formula (4)
(F) means that it can be substituted with hydrogen or fluorine. 6. The method of claim 5,
A liquid crystal composition further comprising at least one compound selected from compounds represented by the following general formulas (5) and (6):
[Chemical Formula 5]

[Chemical Formula 6]

In the above formulas (5) and (6)
R ₇ is alkyl having 1 to 12 carbon atoms,
R ₈ , and R ₉ are each independently hydrogen, oxygen, or alkyl having 1 to 12 carbon atoms,
Ring J is cyclohexyl or phenyl,
i is an integer of 0 or 1,
k is an integer of 1 to 12; The liquid crystal composition according to claim 3 or 5, further comprising a compound represented by the following formula (7).
(7)
P ₁ -Sp ₁ - (K ₁ -Y ₁ ) _a - (K ₂ -Y ₂ ) _b - (K ₃ -Y ₃ ) _c -Sp ₂ -P ₂
In Formula 7,
P ₁ and P ₂ are each independently a polymerizable functional group, a C 1 -C 9 alkyl, alkenyl having 2 to 9, H, F, Cl, or means the CN, and at least one of P ₁ and P ₂ are polymerized Functional group,
Sp ₁ and Sp ₂ are each independently a single bond or a radical of any of the alkyl having 1 to 15 carbon atoms, or at least one hydrogen atom of the radical is substituted with halogen or one or more -CH ₂ - -O-, -O-CO-, or -O-CO-O-, with the proviso that R &
Y ₁ to Y ₃ are each independently _{-CH 2 CH 2 -, -CH =} CH-, -CH 2 O-, -OCH 2 -, -C = C-, -CH 2 CF 2 -, -CHFCHF-, -CF ₂ CH ₂ -, -CH ₂ CHF-, -CHFCH ₂ -, -C ₂ F ₄ -, -O-, -COO-, -OCO-, -CF ₂ O-, -OCF ₂ - ego,
K ₁ to K ₃ are each independently an aromatic ring or a heterocyclic ring composed of 5 to 7 carbons and hydrogen in the ring structure may be substituted with fluorine or an alkoxy radical having 1 to 15 carbon atoms,
a, b, and c are each independently an integer of 0 to 2, and a + b + c is 1 to 3; 11. The method of claim 10,
Wherein Sp ₁ and Sp ₂ are single bonds and P ₁ and P ₂ are each independently any one of the following structures:

. 11. The method of claim 10,
Wherein the compound represented by the formula (7) is represented by any one of the following formulas (7-1) to (7-9):
[Formula 7-1]

[Formula 7-2]

[Formula 7-3]

[Chemical Formula 7-4]

[Formula 7-5]

[Formula 7-6]

[Formula 7-7]

[Formula 7-8]

[Formula 7-9]

In the above formulas (7-1) to (7-9)
P ₁ and P ₂ are as defined in the above formula (7)
Y ₄ and Y ₅ are each independently from each other -CH ₂ CH _{2 -, -CH = CH-, -CH 2} O-, -OCH 2 -, -C = C-, -CH 2 CF 2 -, -CHFCHF- , -CF ₂ CH ₂ -, -CH ₂ CHF-, -CHFCH ₂ -, -C ₂ F ₄ -, -O-, -COO-, -OCO-, -CF ₂ O-, -OCF ₂ - Lt; / RTI &
m1 and m2 are each independently an integer of 1 to 8,
r1 and r2 are each independently an integer of 0 or 1,
R _a and R _b are each independently of the other hydrogen or CH ₃ ,
Ring K is heteroarylene having 5 carbon atoms,
The hydrogen of each ring may be substituted by fluorine or an alkoxy radical of 1 to 15 carbon atoms. 11. The method of claim 10,
Wherein the compound represented by the formula (7) comprises any one of the following compounds:

6. The method of claim 5,
Wherein the liquid crystal composition comprises a compound represented by the formula (1), a compound represented by the formula (2), and a compound represented by the formula (4). 6. The method of claim 5,
Wherein the liquid crystal composition comprises the compound represented by the formula (1) and the compound represented by the formula (3). 16. The method of claim 15,
Wherein the liquid crystal composition comprises at least two compounds represented by the general formula (3). 15. The method of claim 14,
Wherein the liquid crystal composition further comprises at least one compound of the compounds represented by the above formulas (7-2-1) to (7-2-4). 16. The method of claim 15,
Wherein the liquid crystal composition is one comprising at least one compound selected from the group consisting of the compounds represented by the general formulas (7-2) to (7-2-4). A liquid crystal display comprising the liquid crystal composition according to any one of claims 3, 5 and 9. 20. The method of claim 19,
Wherein the liquid crystal display comprises a VA mode, a PSA mode, a PS-VA mode, an IPS mode, or an FFS mode.

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