KR20170073231A - Liquid crystal compound, liquid crystal composition having the compound, and liquid crystal display having the composition - Google Patents

Abstract

The present invention relates to a liquid crystal compound, a liquid crystal composition comprising the liquid crystal compound, and a liquid crystal display device including the liquid crystal composition. The liquid crystal compound has a xylene group.

Description

TECHNICAL FIELD [0001] The present invention relates to a liquid crystal compound, a liquid crystal composition including the liquid crystal compound, and a liquid crystal display device including the liquid crystal composition. BACKGROUND OF THE INVENTION 1. Field of the Invention [0001]

The present invention relates to a liquid crystal compound, a liquid crystal composition comprising the liquid crystal compound, and a liquid crystal display including the liquid crystal composition, and more particularly, to a liquid crystal compound containing a xylene group, a liquid crystal composition containing the liquid crystal compound, And a liquid crystal display device including the liquid crystal composition.

A single liquid crystal compound constituting a liquid crystal preparation has an elongated rod-like molecular structure with an organic substance having a molecular weight of about 200 to 600 g / mol. The liquid crystal molecular structure is divided into a core group for maintaining linearity, a terminal group having flexibility and a linkage group for specific use. The end portion is made of a flexible chain type (alkyl, alkoxy, alkenyl, etc.) which is easily bent on one side or both sides and the side of the other group or central group adopts a polar group (F, CN, OCF ₃ , And the like.

In liquid crystal display (LCD), there are various types such as TN (Twist nematic), IPS (In-plane switching), FFS (Fringe field switching) and VA (Vertical alignment) depending on the characteristics and application mode Do. In such a variety of liquid crystal display devices, it is impossible to make all the required properties of the product such as the temperature of the transparent point, the dielectric anisotropy, the refractive index anisotropy, and the rotational viscosity to be one or two liquid crystal compounds, To prepare a liquid crystal composition.

The liquid crystal compound according to an embodiment of the present invention is represented by the following formula (1).

[Chemical Formula 1]

R ¹ is hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is substituted with -C≡C-, -CH═CH- , -CF ₂ O-, -O-, -COO-, -OCO- or -OCO-O-, or at least one H may be replaced by halogen,

A ¹ and A ² are each independently selected from the group consisting of cyclohexylene, phenylene, tetrahydropyranylene, dioxanylene, cyclohexenylene, 1,4-bicyclopentadiene, Cyclic [2.2.2] octylene, pyridinylene, naphthylene, tetrahydronaphthylene, or decalinylene. In either case, one or more H may be replaced by halogen,

Z ¹ , Z ² and Z ³ are each independently a single bond, -CH ₂ CH ₂ -, -CH═CH-, -C≡C-, -CH ₂ O-, -OCH ₂ -, -CH ₂ CF ₂ -, -CHFCHF-, -CF ₂ CH ₂ -, -CH ₂ CHF-, -CHFCH ₂ -, -C ₂ F ₄ -, -COO-, -OCO-, -CF ₂ O-, -OCF ₂ - or -O-,

L ¹ and L ² are each independently hydrogen, halogen, trifluoromethyl or cyano,

n and m are each independently 0, 1 or 2;

In one embodiment of the present invention, R ¹ can be alkoxy having from 1 to 5 carbon atoms. In one embodiment of the present invention, L ¹ and L ² are fluorine, and Z ¹ , Z ² and Z ³ are each independently a single bond, -CH ₂ O- or -OCH ₂ -.

In one embodiment of the present invention, the liquid crystal compound of Formula 1 may be represented by Formula 1-1 below.

[Formula 1-1]

In one embodiment of the present invention, the liquid crystal compound represented by Formula 1-1 may be selected from the group consisting of Formulas 1-1a to 1-1j.

[Formula 1-1a]

[Formula 1-1b]  

[Formula 1-1c]  

[Chemical Formula (1-1d)  

[Formula 1-1e]  

[Formula 1-1f]  

[Chemical Formula 1-1g]  

[Formula 1-1h]  

[Formula 1-1i]  

[Chemical formula (1-1j)

The liquid crystal composition according to an embodiment of the present invention includes the liquid crystal compound represented by the formula (1).

According to an embodiment of the present invention, the liquid crystal composition may include 1 to 60% by weight of the liquid crystal compound represented by Formula 1, based on the total weight of the liquid crystal composition.

According to an embodiment of the present invention, the liquid crystal composition may further include at least one liquid crystal compound selected from the group consisting of the following general formulas (2) to (5). (2)

R ¹¹ -A ³ -A ⁴ -R ¹²

In Formula 2, R ¹¹ and R ¹² are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is not directly connected to oxygen atoms is _{-C≡C-, -CH = CH-, -CF 2} O-, -O-, -COO- or -OCO-, or substituted or one or more of the H may be replaced by halogen,

A ³ and A ⁴ are each independently cyclohexylene or phenylene,

(3)

R ¹³ -A ⁵ - (A ⁶ ) _p -A ⁷ -R ¹⁴

In Formula 3, R ¹³ and R ¹⁴ are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is not directly connected to oxygen atoms is _{-C≡C-, -CH = CH-, -CF 2} O-, -O-, -COO- or -OCO-, or substituted or one or more of the H may be replaced by halogen,

A ⁵ and A ⁷ are each independently cyclohexylene or phenylene,

A ⁶ is phenylene substituted with cyclohexylene, phenylene or halogen,

p is an integer of 1 or 2,

[Chemical Formula 4]

In Formula 4, R ¹⁵ and R ¹⁶ are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is not directly bonded to oxygen atoms is _{-C≡C-, -CH = CH-, -CF 2} O-, -O-, -COO- or -OCO-, or substituted or one or more of the H may be replaced by halogen,

A ⁸ and A ⁹ are each independently phenylene substituted with cyclohexylene, tetrahydropyranylene, phenylene or halogen,

q is an integer between 0 and 2,

[Chemical Formula 5]

Wherein R ¹⁷ and R ¹⁸ are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is not directly connected to oxygen atoms, -C≡C-, -CH═CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above H may be replaced by halogen,

A ¹⁰ , A ¹¹ and A ¹² are each independently any one of cyclohexylene, tetrahydropyranylene, phenylene and phenylene substituted with halogen,

Z ⁴ and Z ⁵ are each independently _{-CH 2 CH 2 -, -CH =} CH-, -C≡C-, -CH 2 O-, -OCH 2 -, -CH 2 CF 2 -, -CHFCHF-, -CF ₂ CH ₂ -, -CH ₂ CHF-, -CHFCH ₂ -, -C ₂ F ₄ -, -COO-, -OCO-, -CF ₂ O-, -OCF ₂ - or -O-,

r and v are integers between 0 and 1, r + v is 1 or 2,

s and w are integers between 0 and 2;

In one embodiment of the present invention, the liquid crystal composition may further include an antioxidant selected from the group consisting of compounds represented by formulas (6) and (7).

[Chemical Formula 6]

(7)

In the formulas (6) and (7), R ¹⁹ and R ²⁰ are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - -CH = CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above H may be replaced by halogen,

A ¹³ is cyclohexylene, tetrahydropyranylene, or dioxanylene.

In one embodiment of the present invention, the liquid crystal composition may further include a UV stabilizer selected from the group consisting of compounds represented by the following formulas (8) to (10).

[Chemical Formula 8]

Wherein R ²¹ is hydrogen, oxygen, alkyl of 1 to 15 carbon atoms or alkoxy of 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is -C≡C -, -CH = CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above may be replaced by halogen,

 [Chemical Formula 9]

Wherein R ²² and R ²³ are each independently hydrogen, oxygen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is bonded directly to oxygen atoms -CH = CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above H may be replaced by halogen,

f is an integer of 0 to 12,

[Chemical formula 10]

In Formula 10, R ²⁴ is hydrogen, oxygen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is -C≡C- , -CH = CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above may be replaced by halogen,

j is an integer of 0 to 12;

In one embodiment of the present invention, the liquid crystal composition may be employed in a liquid crystal display device. The liquid crystal display device may include a first substrate, a second substrate facing the first substrate, and a liquid crystal layer provided between the first substrate and the second substrate and made of the liquid crystal composition.

The liquid crystal compound according to the embodiment of the present invention and the liquid crystal composition containing the same exhibit high refractive anisotropy and high resistivity under low rotational viscosity. Such a liquid crystal compound and a liquid crystal composition containing the liquid crystal compound can be employed in various liquid crystal display devices, and the liquid crystal display employing the liquid crystal compound and the liquid crystal composition containing the liquid crystal compound has a quick response time.

1 is a schematic block diagram of a liquid crystal display device according to an embodiment of the present invention.
2 is a plan view showing the pixel shown in Fig.
3 is a cross-sectional view taken along the line I-I 'of FIG.

The present invention is capable of various modifications and various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. It should be understood, however, that the invention is not intended to be limited to the particular forms disclosed, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

Hereinafter, preferred embodiments of the present invention will be described in detail.

According to one embodiment of the present invention, there is provided a liquid crystal compound represented by the following formula (1).

[Chemical Formula 1]

In Formula 1,

R ¹ is hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one of -CH ₂ - of the alkyl or alkoxy is not bonded directly to -C≡C-, -CH═CH- , -CF ₂ O-, -O-, -COO-, -OCO- or -OCO-O-, or at least one H may be replaced by halogen.

A ¹ and A ² are each independently selected from the group consisting of cyclohexylene, phenylene, tetrahydropyranylene, dioxanylene, cyclohexenylene, 1,4-bicyclopentadiene, Cyclic [2.2.2] octylene, pyridinylene, naphthylene, tetrahydronaphthylene, or decalinylene. As either, at least one H may be replaced by a halogen.

Z ¹ , Z ² and Z ³ are each independently a single bond, -CH ₂ CH ₂ -, -CH═CH-, -C≡C-, -CH ₂ O-, -OCH ₂ -, -CH ₂ CF ₂ -, -CHFCHF-, -CF ₂ CH ₂ -, -CH ₂ CHF-, -CHFCH ₂ -, -C ₂ F ₄ -, -COO-, -OCO-, -CF ₂ O-, -OCF ₂ - or -O-.

L ¹ and L ² are each independently hydrogen, halogen, trifluoromethyl or cyano.

n and m are each independently 0, 1 or 2;

Unless defined otherwise herein, the following terms may be defined as follows.

The halogen may be fluorine (F), chlorine (Cl), bromine (Br) or iodine (I).

The alkyl having 1 to 15 carbon atoms may be linear, branched or cyclic. Specifically, alkyl of 1 to 15 carbon atoms is straight chain alkyl of 1 to 10 carbon atoms; Straight chain alkyl of 1 to 5 carbon atoms; Branched or cyclic alkyl having from 3 to 10 carbon atoms; Or branched or cyclic alkyl having 3 to 5 carbon atoms. More specifically, alkyl having 1 to 15 carbon atoms can be methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl, n-pentyl, isopentyl or cyclohexyl.

The alkoxy of 1 to 15 carbon atoms may be straight chain, branched chain or cyclic alkoxy. Specifically, alkoxy of 1 to 15 carbon atoms is straight chain alkoxy of 1 to 10 carbon atoms; Straight chain alkoxy having 1 to 5 carbon atoms; Branched or cyclic alkoxy having 3 to 10 carbon atoms; Or branched or cyclic alkoxy of 3 to 5 carbon atoms. More specifically, the alkoxy having 1 to 15 carbon atoms is preferably methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, iso-butoxy, Ethoxy or cyclohexyl.

The alkyl or alkoxy having 1 to 15 carbon atoms may be substituted by one or more of -CH ₂ -, -C≡C-, -CH═CH-, -CF ₂ O-, -O-, -COO-, -OCO- or -OCO -O-. ≪ / RTI > As an example, methyl can be replaced by vinyl (-CH = CH-H) in which -CH ₂ - of methyl (-CH ₂ -H) is replaced by -CH = CH-. Provided that at least one of -CH ₂ - in the above may be substituted with the substituent described above so that oxygen atoms are not directly connected.

Also, alkyl and alkoxy having 1 to 15 carbon atoms can be replaced with one or more of the above H is substituted with halogen. As an example, methyl may be replaced by perfluoromethyl (-CF ₃ ) in which all H of methyl (-CH ₃ ) is replaced by F.

A single bond means a case where no additional atom is present in a portion represented by Z ¹ to Z ⁵ . In one embodiment, Z ¹ is a single bond in the formula (1), the xylene ring when n is 0 and m is directly connected to the benzene ring can form a structure.

The liquid crystal compound of Formula 1 includes a xylene group and can exhibit a remarkably reduced viscosity compared to conventional liquid crystal compounds while maintaining high dielectric anisotropy and refractive index anisotropy. In particular, the liquid crystal compound of formula (1) exhibits a remarkably reduced viscosity compared to a liquid crystal compound containing a conventional 4-alkylcyclohexyl group and exhibits excellent physical properties. Accordingly, when the liquid crystal compound of Formula 1 is used, it is possible to provide a liquid crystal display device capable of exhibiting excellent physical properties and fast response.

The liquid crystal compound of Formula 1 has a polar functional group on the side of the center group and exhibits negative dielectric anisotropy. Accordingly, when the liquid crystal compound of Formula 1 is used, it is possible to use VA (Virtical Alignment), MVA (Multidomain Virtical Alignment), PVA (Patterned Virtical Alignment), PS (Polymer Stabilized Virtical Alignment) (In-Plane Switching) mode and the like can be realized.

The liquid crystal compound of the formula (1) has the following structure, and can exhibit lower viscosity together with better physical properties.

Specifically, a liquid crystal compound in which R ^{1 in} formula (1) is alkoxy having 1 to 5 carbon atoms can exhibit higher dielectric anisotropy and lower viscosity.

The liquid crystal compound in which A ¹ and A ² in Formula (1) are each independently phenylene substituted with cyclohexylene, phenylene, and halogen can be driven at a low voltage, and sufficient Low-temperature stability, high-dielectric anisotropy and high-refractive anisotropy.

Further, the liquid crystal compound in which L ¹ and L ² in formula (1) are each independently any one of halogen and trifluoromethyl can exhibit high negative dielectric anisotropy.

Meanwhile, Z ¹ , Z ² and Z ³ connecting the central groups in Formula 1 may be appropriately selected from the substituents described above depending on the use of the liquid crystal compound. In one example, Z ¹ , Z ^2, and Z ³ may each independently be a single bond, -CH ₂ O-, or -OCH ₂ -.

More specifically, the liquid crystal compound represented by Formula 1 may be a liquid crystal compound represented by Formula 1-1.

[Formula 1-1]

R ₁ , A ₁ , Z ₁ , Z ₂ , L ₁ , and L ₂ are the same as defined in formula (1).

The liquid crystal compound represented by Formula 1-1 may be a liquid crystal compound selected from the group consisting of Formulas 1-1a to 1-1j.

[Formula 1-1a]  

[Formula 1-1b]  

[Formula 1-1c]  

[Chemical Formula (1-1d)  

[Formula 1-1e]  

[Formula 1-1f]  

[Chemical Formula 1-1g]  

[Formula 1-1h]  

[Formula 1-1i]  

[Chemical Formula (1-1j)

 According to another embodiment of the present invention, there is provided a liquid crystal composition comprising the liquid crystal compound represented by Formula 1 above.

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 about 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 about 60% by weight or less based on the total weight of the liquid crystal composition. 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 composition may further comprise various liquid crystal compounds in addition to the liquid crystal compound of formula (1) for the purpose of performance of the liquid crystal display device.

For example, the liquid crystal composition may further include a conventionally known low viscosity liquid crystal compound. As such a liquid crystal compound having a low viscosity, a liquid crystal compound represented by the following formula 2 may be used.

(2)

R ¹¹ -A ³ -A ⁴ -R ¹²

In Formula 2, R ¹¹ and R ¹² are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is not directly connected to oxygen atoms -C≡C-, -CH═CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above H may be replaced by halogen.

A ³ and A ⁴ are each independently cyclohexylene or phenylene.

The liquid crystal compound represented by Formula 2 may be at least one liquid crystal compound selected from the group consisting of compounds represented by Formula 2-1 and Formula 2-2. The liquid crystal compounds represented by the following formulas (2-1) and (2-2) can be used to easily control the transparent point, the rotational viscosity, the refractive index anisotropy and the dielectric anisotropy of the liquid crystal composition while maintaining a high specific resistance.

[Formula 2-1]

[Formula 2-2]

In Formula 2-1 and 2-2, R ¹¹ and R ¹² may be defined as R ¹¹ and R ¹² of formula (II).

In one embodiment of the present invention, the content of the component (2) may be about 5% by weight to about 40% by weight. When the content exceeds about 40% by weight, it is difficult to control the dielectric anisotropy, . Also, when less than about 5% by weight is used, the effect of low viscosity is deteriorated.

As another example, the liquid crystal composition may further include a liquid crystal compound known in the art as a liquid crystal compound having a high phase transition temperature or a high refractive index. As such a liquid crystal compound, a liquid crystal compound represented by the following formula (3) can be used.

(3)

R ¹³ -A ⁵ - (A ⁶ ) _p -A ⁷ -R ¹⁴

In Formula 3, R ¹³ and R ¹⁴ are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is not directly connected to oxygen atoms -C≡C-, -CH═CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above H may be replaced by halogen.

A ⁵ and A ⁷ are each independently cyclohexylene or phenylene.

A ⁶ is phenylene substituted with cyclohexylene, phenylene or halogen.

p is an integer of 1 or 2;

The liquid crystal compound represented by Formula 3 may be at least one liquid crystal compound selected from the following Formulas 3-1 to 3-5. The liquid crystal compounds represented by the following formulas (3-1) and (3-5) can be used to easily control the transparent point, the rotational viscosity, the refractive index anisotropy and the dielectric anisotropy of the liquid crystal composition while maintaining a high specific resistance.

[Formula 3-1]

[Formula 3-2]

[Formula 3-3]

[Chemical Formula 3-4]

[Formula 3-5]

In Formula 3-1 to 3-5, R ¹³ and R ¹⁴ may be defined as R ¹³ and R ¹⁴ of formula (3).

In one embodiment of the present invention, the material of Formula 3 may be used in about 2% to about 50% by weight of the liquid crystal composition. For the high-temperature effect, about 2 wt% to about 40 wt% of liquid crystal compounds represented by Formulas 3-1 to 3-4 are used, and about 2 wt% of the liquid crystal compound represented by Formula 3-5 is used for high refractive index anisotropy. To about 20% by weight. When the weight percentage of the liquid crystal compound of the formula (3) exceeds about 50% by weight in the liquid crystal composition, the low temperature stability is adversely affected and it is difficult to control the dielectric anisotropy to -2.0 or less.

As another example, the liquid crystal composition may further include a conventionally known medium-flowable liquid crystal compound. As such a middle-liquid-crystalline liquid crystal compound, a liquid crystal compound represented by the following formula (4) may be used.

[Chemical Formula 4]

In Formula 4, R ¹⁵ and R ¹⁶ are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is not directly bonded to oxygen atoms -C≡C-, -CH═CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above H may be replaced by halogen.

A ⁸ and A ⁹ are each independently phenylene substituted with cyclohexylene, tetrahydropyranylene, phenylene or halogen.

and q is an integer of 0 to 2.

The liquid crystal compound represented by Formula 4 may be at least one liquid crystal compound selected from the group consisting of the following Formulas 4-1 to 4-4. The liquid crystal compounds represented by the following formulas (4-1) and (4-4) can be used to easily control the transparent point, the rotational viscosity, the refractive index anisotropy and the dielectric anisotropy of the liquid crystal composition while maintaining a high specific resistance.

[Formula 4-1]

[Formula 4-2]

[Formula 4-3]

[Formula 4-4]

In Formula 4-1 to 4-4, R ¹⁵ and R ¹⁶ may be defined as R ¹⁵ and R ¹⁶ of formula (4).

In one embodiment of the present invention, the liquid crystal compound represented by Formula 4 may be contained in the liquid crystal composition in an amount of about 10 to less than about 80% by weight, and three or more kinds may be used for low temperature stability of the composition. The liquid crystal compound represented by Formula 4 may be used in an amount of about 10% by weight or more to control the dielectric anisotropy to -2.0 or more, but if it exceeds about 80% by weight, the viscosity of the liquid crystal compound may be excessively increased.

As another example, the liquid crystal composition may further include a conventionally known high-k liquid crystal compound. As such a liquid crystal compound, a liquid crystal compound represented by the following formula (5) may be used.

[Chemical Formula 5]

Wherein R ¹⁷ and R ¹⁸ are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is not directly connected to oxygen atoms, -C≡C-, -CH═CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above H may be replaced by halogen.

A ¹⁰ , A ¹¹ and A ¹² are each independently any one of cyclohexylene, tetrahydropyranylene, phenylene and phenylene substituted with halogen.

Z ⁴ and Z ⁵ are each independently _{-CH 2 CH 2 -, -CH =} CH-, -C≡C-, -CH 2 O-, -OCH 2 -, -CH 2 CF 2 -, -CHFCHF-, -CF ₂ CH ₂ -, -CH ₂ CHF-, -CHFCH ₂ -, -C ₂ F ₄ -, -COO-, -OCO-, -CF ₂ O-, -OCF ₂ - or -O-.

r and v are integers between 0 and 1, and r + v is 1 or 2.

s and w are integers between 0 and 2;

The liquid crystal compound represented by Formula 5 may be at least one liquid crystal compound selected from the group consisting of the following Formulas 5-1 to 5-4. The liquid crystal compounds represented by the following formulas (5-1) and (5-4) can be used to easily control the transparent point, the rotational viscosity, the refractive index anisotropy and the dielectric anisotropy of the liquid crystal composition while maintaining a high specific resistance.

[Formula 5-1]

[Formula 5-2]

[Formula 5-3]

[Formula 5-4]

In Formula 5-1 to 5-4, R ¹⁷ and R ¹⁸ may be defined as R ¹⁷ and R ¹⁸ of formula (5).

In one embodiment of the present invention, the liquid crystal compound represented by Formula 5 may include 0 wt% to 30 wt% of the liquid crystal composition. The liquid crystal compound represented by the formula (5) is required for realizing the high-dielectric constant liquid crystal composition, and when it exceeds 30% by weight, the reliability of the display such as the voltage holding ratio (VHR) may be deteriorated.

The liquid crystal composition may suitably include at least one liquid crystal compound of the liquid crystal compounds represented by the above formulas (2) to (5) in view of the intended use and effects of the liquid crystal composition. In particular, the liquid crystal composition may include a liquid crystal compound represented by the general formulas (2), (3) and (4) in order to improve various physical properties of the liquid crystal composition in a balanced manner. At this time, one or more liquid crystal compounds may be used as the liquid crystal compounds represented by the general formulas (2) to (4).

In addition to the liquid crystal compound, the liquid crystal composition may further include various additives conventionally used in the art to which the present invention pertains.

Specifically, the liquid crystal composition may further include an antioxidant. Examples of such antioxidants include antioxidants selected from the group consisting of compounds represented by the following formulas (6) and (7).

[Chemical Formula 6]

(7)

In the formulas (6) and (7), R ¹⁹ and R ²⁰ are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - -CH = CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above H may be replaced by halogen.

A ¹³ is cyclohexylene, tetrahydropyranylene, or dioxanylene.

In addition, the liquid crystal composition may further include a UV stabilizer. As such UV stabilizer, Hals (Hindered amine light stabilizer) series can be used. As a non-limiting example, UV stabilizers selected from the group consisting of the compounds represented by the following formulas (8) to (10) can be used.

[Chemical Formula 8]

Wherein R ²¹ is hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one of -CH ₂ - of the alkyl or alkoxy is not bonded directly to -C≡C-, -CH = CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above can be replaced by halogen.

 [Chemical Formula 9]

In Formula 9, R ²² and R ²³ are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is not directly connected to oxygen atoms -C≡C-, -CH═CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above H may be replaced by halogen.

f is an integer of 0 to 12;

[Chemical formula 10]

Wherein R ²⁴ is hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one of -CH ₂ - of the alkyl or alkoxy is not bonded directly to -C≡C-, CH = CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above can be replaced by halogen.

j is an integer of 0 to 12;

The antioxidant and / or UV stabilizer may be used in an amount of about 1 to 2,000 ppm or about 200 to 500 ppm based on the total weight of the liquid crystal composition. When the antioxidant and / or UV stabilizer is contained in the liquid crystal composition in an amount exceeding 2,000 ppm, the physical properties of the liquid crystal composition, particularly the reduction of the transparent point, may be large. In addition, additives with high melting points have a bad influence on low-temperature stability. Therefore, it is appropriate that the additive is contained at 2,000 ppm or less. The liquid crystal composition having a dielectric anisotropy of 0 to -4.0 can be used at 200 to 500 ppm.

The liquid crystal composition described above can be employed in a liquid crystal display device. This will be described with reference to the drawings.

1 is a schematic block diagram of a liquid crystal display device according to an embodiment of the present invention.

Referring to FIG. 1, a liquid crystal display according to an embodiment of the present invention includes a display panel PNL, a timing controller TC, a gate driver GDV, and a data driver DDV.

The display panel PNL may be a liquid crystal panel including a first substrate, a second substrate, and a liquid crystal layer disposed between the two substrates.

The display panel PNL includes a plurality of gate lines GL1 to GLm extending in a first direction D1 (e.g., a row direction) and a plurality of gate lines GL1 to GLm extending in a second direction D2 And a plurality of data lines DL1 to DLn extending in the column direction. The display panel PNL may include a plurality of pixels PX. The plurality of pixels PX may be arranged in the first direction D1 and the second direction D2.

The timing controller TC receives image data RGB and a control signal from an external graphic controller (not shown). The control signal is a high-level data enable signal for only a period in which data is output for displaying a vertical synchronizing signal (Vsync) as a frame distinguishing signal, a horizontal synchronizing signal (Hsync) as a row discriminating signal, A signal DES and a main clock signal MCLK.

The timing controller TC converts the image data RGB according to the specification of the data driver DDV and outputs the converted image data DATA to the data driver DDV. The timing controller TC generates a gate control signal GS1 and a data control signal DS1 based on the control signal. The timing controller TC outputs the gate control signal GS1 to the gate driver GDV and outputs the data control signal DS1 to the data driver DDV. The gate control signal GS1 is a signal for driving the gate driver GDV and the data control signal DS1 is a signal for driving the data driver DDV.

The gate driver GDV generates a gate signal based on the gate control signal GS1 and outputs the gate signal to the gate lines GL1 to GLm. The gate control signal GS1 includes at least one clock signal for controlling an output period of the scan start signal and the gate on voltage for instructing the start of scanning and an output enable signal for limiting the duration of the gate on voltage .

The data driver DDV generates a gradation voltage according to the image data DATA based on the data control signal DS1 and outputs the gradation voltage to the data lines DL1 to DLn with a data voltage. The data voltage may include a positive data voltage having a positive value for the common voltage and a negative data voltage having a negative value. The data control signal DS1 includes a horizontal start signal STH informing the start of the transmission of the image data DATA to the data driver DDV, a load for applying a data voltage to the data lines DL1- A signal, and an inverted signal that inverts the polarity of the data voltage with respect to the common voltage, and the like.

Each of the timing controller TC, the gate driver GDV and the data driver DDV may be directly mounted on the display panel PNL in the form of at least one integrated circuit chip, mounted on a printed circuit board, attached to the display panel PNL in the form of a tape carrier package (TCP), or mounted on a separate printed circuit board. Alternatively, at least one of the gate driver (GDV) and the data driver (DDV) may be connected to the display panel (PNL) along with the gate lines GL1 to GLm, the data lines DL1 to DLn, ). ≪ / RTI > Also, the timing controller TC, the gate driver GDV, and the data driver DDV may be integrated into a single chip.

FIG. 2 is a plan view of the pixel shown in FIG. 1, and FIG. 3 is a cross-sectional view taken along the line I-I 'of FIG.

Referring to FIGS. 2 and 3, the liquid crystal display according to an exemplary embodiment of the present invention may include a plurality of pixels PX for displaying an image. In FIG. 2, one of a plurality of pixels is representatively shown. The remaining pixels are not shown separately because they have substantially the same structure as the above-described structure.

The pixel PX is provided between data lines sequentially arranged in the first direction D1 and between adjacent gate lines. In the present embodiment, a gate line to which one pixel is connected is referred to as a gate line GL, and a data line to which the pixel is connected is referred to as a first data line DL for convenience of explanation.

A liquid crystal display device 10 according to an embodiment of the present invention includes a first substrate 100, a second substrate 200, and a liquid crystal layer interposed between the first substrate 100 and the second substrate 200 (300).

The first substrate 100 includes a first base substrate 110, gate lines GL, data lines DL, thin film transistors TFT, pixel electrodes PE, and first alignment layers AL1 ).

The first base substrate 110 has pixel regions PA provided with respective pixels. Although the pixel region PA has a rectangular shape elongated in one direction, it is not limited thereto. The shape of the pixel area PA may be variously modified, such as a V shape or a Z shape.

The pixel region PA includes a gate line GL, a data line DL, a thin film transistor TFT, and a pixel electrode PE.

The gate line GL extends in one direction on the first base substrate 110. The data lines DL are provided on the first base substrate 110 so as to be insulated from the gate lines GL.

The thin film transistor TFT is provided adjacent to an intersection of the gate line GL and the data line DL. The thin film transistor TFT includes a gate electrode GE branched from the gate line GL and a source electrode SE branched from the data line DL and a drain electrode DE spaced from the source electrode SE ).

The pixel electrode PE is connected to the drain electrode DE.

Referring to FIG. 3, the gate line GL and the gate electrode GE are provided in the pixel region PA on the first base substrate 110.

A semiconductor pattern SM is provided on the gate line GL with a first insulating layer 111 therebetween. The data line DL, the source electrode SE, and the drain electrode DE are provided on the first base substrate 110 on which the semiconductor pattern SM is formed. Here, the semiconductor pattern SM forms a conductive channel between the source electrode SE and the drain electrode DE.

A second insulating layer 113 is formed on the first insulating layer 111 on which the source electrode SE and the drain electrode DE are formed. A passivation layer 115 is formed on the second insulating layer. The pixel electrode PE is provided on the passivation layer 115 and electrically connected to the drain electrode DE through the contact hole CH formed through the second insulating layer 113 and the passivation layer 115. [ Lt; / RTI >

A first alignment layer AL1 is provided on the pixel electrode PE. The first alignment layer AL1 is made of a compound including a polymer selected from the group consisting of polyamic acid, polyimide and combinations thereof, and an epoxy crosslinking agent for pre-tilting the liquid crystal molecules.

The second substrate 200 is provided opposite to the first substrate 100. The second substrate 200 includes a second base substrate 210, color filters CF, a black matrix BM, a common electrode CE, and a second alignment layer AL2.

The color filters CF and the black matrix BM are provided on the second base substrate 210. The common electrode CE and the second alignment layer AL2 are sequentially formed on the color filters CF and the black matrix BM.

The color filters CF are provided corresponding to the pixel regions PA. Each color filter (CF) implements either red, green or blue. The black matrix BM is formed between the color filters CF and blocks light passing through the liquid crystal layer 300 between the color filters CF. The common electrode CE is provided on the color filters CF and the black matrix BM.

In an embodiment of the present invention, it is shown that the color filter CF is provided in the second substrate 200, but it is not limited thereto. In another embodiment, the color filter CF may be provided in the first substrate 100 .

The second alignment layer AL2 is formed to cover the common electrode CE. The second alignment layer AL2 may be made of a compound including a polyamic acid, a polyimide, a polymer selected from the group consisting of polyimide and a combination thereof, and an epoxy crosslinking agent to pre-tilt the liquid crystal molecules.

The liquid crystal layer 300 is provided between the first alignment layer AL1 and the second alignment layer AL2.

When the thin film transistor TFT is turned on in response to a driving signal provided through the gate line GL, an image signal provided through the data line DL is supplied to the thin film transistor TFT through the turned- And is provided as a pixel electrode PE. Accordingly, an electric field is formed between the pixel electrode PE and the common electrode CE to which a common voltage is applied. The liquid crystal molecules of the liquid crystal layer 300 are driven according to the electric field, and as a result, an image is displayed according to the amount of light transmitted through the liquid crystal layer 300.

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

In this embodiment, the liquid crystal display device of the most basic form has been disclosed, but it is not limited thereto, and it goes without saying that the present invention can be applied to other modes of liquid crystal display devices requiring a fast response time. For example, in an embodiment of the present invention, the pixel electrode and the common electrode are formed as a through plate. However, in another embodiment, at least one of the pixel electrode and the common electrode may have a shape other than the through-hole, for example, Pattern can be added. Although the pixel electrode and the common electrode are formed on different substrates in the exemplary embodiment of the present invention, the pixel electrode and the common electrode may be formed on one substrate, for example, And may be provided on the first substrate. Accordingly, the liquid crystal composition can be applied to liquid crystal display devices of various modes such as a vertical alignment (VA) mode, a fringe field switching (FFS) mode, an in plane switching (IPS) mode, and a plane to light switching have.

Particularly, since the liquid crystal composition according to an embodiment of the present invention exhibits high negative dielectric anisotropy and high refractive index anisotropy even under a low rotational viscosity, VA, MVA (Multidomain Virtical Alignment), PVA Patterned Virtical Alignment, Polymer Stabilized Virtical Alignment (PS-VA), and the like.

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.

1. Method for producing a liquid crystal compound of the formula 1-1a

A liquid crystal compound of 4-ethoxy-2,3-difluoro-3 ", 4" -dimethyl terphenyl was prepared by the following method.

[Reaction Scheme 1]

A 1 30.0g (0.129mol) in a nitrogen atmosphere was dissolved in anhydrous tetrahydrofuran. After cooling to -70 캜 using an ice bath, 77.5 ml of 2.5 M concentration n-butyllithium was added dropwise. After stirring for 1 hour, 28.8 g (0.258 mol) of trimethylborate 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. To the reaction solution, a 1N aqueous hydrochloric acid solution was poured to pH 2, and the product was extracted with diethyl ether. The organic layer was washed with distilled water and dried over magnesium sulfate. heptane solution to give product 2 .

Was dissolved in 3 46.9g (0.166mol) and 4 30.4g (0.151mol) in toluene in a nitrogen atmosphere, it was added potassium carbonate aqueous solution of 2M concentration. After the temperature was raised to 60 ℃, the addition of _{Pd (PPh 3) 4 8.7g (} 0.008mol) and refluxed overnight. After cooling, 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. Elution on silica gel column with a 10: 1 solution of n-heptane: ethyl acetate = yields product 5 .

2 20.0 g (0.148 mol) and 5 38.6 g (0.123 mol) of toluene were dissolved in toluene under a nitrogen stream, and a 2 M potassium carbonate aqueous solution was added. After the temperature was raised to 80 ℃, the addition of _{Pd (PPh 3) 4 9.2g (} 0.008mol) and refluxed overnight. After cooling, 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. Elution on silica gel column with n-heptane solution gave the product 6 .

_{^{1 H NMR (S = CDCl 3}} , δ in ppm): 7.67 (m, 1H, Ar- H), 7.43 (m, 1H, Ar- H), 7.25 (d, 4H, Ar- H), 7.15 (m 3H, Ar- H ), 4.09 (m, 2H, OC H2 -CH3), 2.34 (m, 6H, Ar- (C H3) 2 ), 1.32 (t, 3H, CH2-C H3 ).

2. Method for producing liquid crystal compound of formula 1-1b

Bromo-4-iodobenzene (3) instead of 1-bromo-4-iodobenzene (3) in Reaction Scheme 1, the 4-ethoxy-2,3,3'- -2-fluoro-4-iodobenzene. ≪ / RTI >

_{^{1 H NMR (S = CDCl 3}} , δ in ppm): 7.83 (m, 1H, Ar- H), 7.67 (d, 1H, Ar- H), 7.58 (m, 1H, Ar- H), 7.43 (m , 1H, Ar- H), 7.15 (m, 2H, Ar- H), 7.05 (m, 2H, Ar- H), 4.09 (m, 2H, OC H2 -CH3), 2.34 (m, 6H, Ar- (C H3) 2 ), 1.32 (t, 3H, CH2-C H3 ).

3. Method for producing liquid crystal compound of formula 1-1c

The liquid crystal compound of 4 '- ((4-ethoxy-2,3-difluorophenoxy) methyl) -3,4-dimethyl-1,1'-biphenyl was prepared as follows.

[Reaction Scheme 2]

2 20.0 g (0.133 mol) and 31.3 g (0.111 mol) of 3 31.3 g (0.111 mol) were dissolved in toluene under a nitrogen stream, followed by the addition of a 2M aqueous solution of potassium carbonate. After the temperature was raised to 60 ℃, the addition of _{Pd (PPh 3) 4 7.7g (} 0.007mol) and refluxed overnight. After cooling, 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. The product 7 was obtained by eluting with a n-heptane solution on a silica gel column.

Under a nitrogen stream, 7 25.0 g (0.095 mol) of 7 was dissolved in anhydrous tetrahydrofuran. After cooling to -70 ° C using an ice bath, 45.9 ml of 2.5 M n-butyllithium was added dropwise. After stirring for 1 hour, the temperature was raised to room temperature and stirred for 1 hour. The reaction solution was slowly added dropwise to an anhydrous tetrahydrofuran solution containing excess dry ice. The resulting solid was separated to give the product 8 .

Under nitrogen flow, 19.7 g (0.093 mol) of 8 were dissolved in anhydrous tetrahydrofuran. After cooling to -30 ° C using an ice bath, 70.0 ml of 2M borane dimethyl sulfide was added. After stirring for 1 hour, the temperature was raised to room temperature and stirred for 12 hours. The reaction solution was diluted with water and diethyl, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulfate. Elution on silica gel column with n-heptane solution gave the product 9 .

9 16.3 g (0.076 mol) of 9 were dissolved in dichloromethane under a nitrogen stream, and then 21.4 ml of triethylamine was added. After cooling to -30 캜 using an ice bath, the mixture was added dropwise to 14.5 g of tosyl chloride. . After stirring for 1 hour, the temperature was raised to room temperature and stirred for 12 hours. The reaction solution was diluted with water and dichloromethane, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulphate to give product 10 .

10 17.5 (0.047 mol) and 9.9 g (0.057 mol) of 11 9.9 g (0.057 mol) were dissolved in dimethylformamide under a nitrogen stream, and then 13 g of potassium carbonate was added. After raising the temperature to 100 占 폚, the mixture was refluxed overnight. After cooling, the reaction solution was diluted with water and diethyl, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulfate. eluting with a 10: 1 solution of n-heptane: ethyl acetate on a silica gel column to give the product 12 .

_{^{1 H NMR (S = CDCl 3}} , δ in ppm): 7.67 (d, 1H, Ar- H), 7.40 (m, 4H, Ar- H), 7.15 (m, 2H, Ar- H), 6.63 (m , 2H, Ar- H), 5.16 (m, 2H, Ar-OC H2 -Ar), 4.09 (m, 2H, OC H2 -CH3), 2.34 (m, 6H, Ar- (C H3) 2), 1.32 (t, 3H, CH2-C H3 ).

The physical properties of this compound were Δε = -6.8, γ ₁ = 128, and Cr 94.3 I.

4. Method for producing liquid crystal compound of formula 1-1d

The liquid crystal compound of 1 - ((4- (3,4-dimethylphenyl) cyclohexyl) methoxy) -4-ethoxy-2,3-difluorobenzene was prepared by the following method.

[Reaction Scheme 3]

A 1 50.0g (0.215mol) in a nitrogen atmosphere was dissolved in anhydrous tetrahydrofuran. After cooling to -70 캜 using an ice bath, 104.3 ml of 2.5M n-butyllithium was added dropwise. After stirring for 1 hour, it was dripped by dissolving 13 40.3g (0.258mol) in dry tetrahydrofuran. After stirring for 1 hour, the temperature was raised to room temperature and stirred for 1 hour. The reaction solution was diluted with water and diethyl, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulfate. The product 14 was eluted on a silica gel column with a 3: 1 solution of n-heptane: ethyl acetate = 3: 1.

14 34.2 (0.130 mol) was dissolved in toluene under a nitrogen stream, and 2.4 g of paratoluenesulfonic acid was added. The temperature was raised to 110 DEG C and refluxed overnight. After cooling, the reaction solution was diluted with water and diethyl, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulfate. eluting on a silica gel column with n-heptane solution to give the product 15 .

15 (0.111 mol) was dissolved in ethanol, followed by the addition of 5.4 g of 10 wt% Pd / C. The mixture was stirred at room temperature for 6 hours under a hydrogen gas pressure of 6 atm. 10wt% Pd / C was filtered and the solvent was removed. Recrystallization in ethanol gave the product 16 .

16 24.6 (0.100 mol) was dissolved in toluene under a nitrogen stream, and then 188.6 ml of formic acid was added. After stirring at room temperature for 12 hours, the reaction solution was diluted with water and diethyl, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulfate to give the product 17 .

17 45.6 g (0.133 mol) of 17 were dissolved in a nitrogen stream under the action of a tibutyl methyl ether. After cooling to -30 캜 using an ice bath, 14.9 g of potassium thiobutoxide was added dropwise. After stirring for 1 hour, 20 20.7 (0.102 mol) 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. 1.5 liters of n-heptane was added to the reaction solution to separate the resulting solid, and then the organic layer was dried to obtain a product 18 .

18 18.4 (0.080 mol) was dissolved in anhydrous tetrahydrofuran under a nitrogen stream, and then 100 ml of a 1N hydrochloric acid aqueous solution was added. After raising the temperature to 60 占 폚, the mixture was stirred for 6 hours. After cooling, the reaction solution was diluted with a saturated aqueous solution of sodium hydrogencarbonate and diethyl, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulfate to give the product 19 .

17.1 g (0.079 mol) of 19 were dissolved in anhydrous tetrahydrofuran under a nitrogen stream. After cooling to -30 ° C using an ice bath, 59.3 ml of 2M borane dimethyl sulfide was added. After stirring for 1 hour, the temperature was raised to room temperature and stirred for 12 hours. The reaction solution was diluted with water and diethyl, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulfate. Elution on silica gel column with n-heptane solution gave the product 20 .

Under nitrogen stream, 15.9 g (0.072 mol) of 20 were dissolved in dichloromethane, and then 20.3 ml of triethylamine was added. After cooling to -30 캜 using an ice bath, the mixture was added dropwise to 13.9 g of tosyl chloride. After stirring for 1 hour, the temperature was raised to room temperature and stirred for 12 hours. The reaction solution was diluted with water and dichloromethane, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulfate to give the product 21 .

21 18.0 (0.048 mol) and 11 10.1 g (0.058 mol) of 11 18 g (0.058 mol) were dissolved in dimethylformamide under a nitrogen stream, and 13 g of potassium carbonate was added. After raising the temperature to 100 占 폚, the mixture was refluxed overnight. After cooling, the reaction solution was diluted with water and diethyl, and the phases were separated. The organic layer was then extracted, washed with distilled water and dried over magnesium sulfate. Elution on silica gel column with a 10: 1 solution of n-heptane: ethyl acetate = yields product 22 .

_{^{1 H NMR (S = CDCl 3}} , δ in ppm): 7.03 (m, 3H, Ar- H), 6.63 (m, 2H, Ar- H), 4.09 (m, 2H, OC H2 -CH3), 3.90 ( m, 2H, Ar-OC H2 -Ar), 2.72 (m, 1H, Cy-H), 2.32 (m, 6H, Ar- (C H3) 2), 1.90 (m, 5H, Cy-H), 1.30 (m, 4H, Cy-H), 1.32 (t, 3H, CH2-C H3 ).

The physical properties of this compound were Δε = -7.0, γ ₁ = 129, and Cr 76.8 I.

5. Method for producing liquid crystal compound of formula 1-1e

The liquid crystal compound of 4-butoxy-2,3-difluoro-3 ", 4 " -dimethyl terphenyl is obtained in the second step from 4-ethoxy-2,3-difluorophenylboronic acid (4) But substituting 4-butoxy-2,3-difluorophenylboronic acid according to the preparation described in [1-1a].

_{^{1 H NMR (S = CDCl 3}} , δ in ppm): 7.67 (m, 1H, Ar- H), 7.43 (m, 1H, Ar- H), 7.25 (d, 4H, Ar- H), 7.15 (m , 3H, Ar- H), 4.09 (m, 2H, OC H2 -CH2-CH2-CH3), 2.34 (m, 6H, Ar- (C H3) 2), 1.76 (m, 2H, O-CH2-C H2 --CH2 --CH3), 1.45 (m, 2H, O - CH2 --CH2 --CH2 --CH3), 0.90 (t, 3H, CH2 --C13 ).

6. Method for producing liquid crystal compound of formula 1-1f

4-Butoxy-2,3,3'-trifluoro-3 ", 4" -dimethyl terphenyl In place of 4-ethoxy-2,3-difluorophenylboronic acid (4) 4-butoxy-2,3-difluorophenylboronic acid.

_{^{1 H NMR (S = CDCl 3}} , δ in ppm): 7.83 (m, 1H, Ar- H), 7.67 (d, 1H, Ar- H), 7.58 (m, 1H, Ar- H), 7.43 (m , 1H, Ar- H), 7.15 (m, 2H, Ar- H), 7.05 (m, 2H, Ar- H), 4.09 (m, 2H, OC H2 -CH2-CH2-CH3), 2.34 (m, 6H, Ar- (C H3) 2 ), 1.76 (m, 2H, O-CH2-C H2 -CH2-CH3), 1.45 (m, 2H, O-CH2-CH2- CH2 -CH3), 0.90 (t, 3H, CH2-C H3 ).

7. Method for producing liquid crystal compound of formula 1-1g

The 4 '- ((4-butoxy-2,3-difluorophenoxy) methyl) -3,4-dimethyl-1,1'-biphenyl compound is prepared by reacting 4-ethoxy- -Butoxy] -2,3-difluorophenol in place of di-fluorophenol (13).

_{^{1 H NMR (S = CDCl 3}} , δ in ppm): 7.67 (d, 1H, Ar- H), 7.40 (m, 4H, Ar- H), 7.14 (m, 2H, Ar- H), 6.63 (m , 2H, Ar- H), 5.16 (m, 2H, Ar-OC H2 -Ar), 4.06 (m, 2H, OC H2 -CH3), 2.34 (m, 6H, Ar- (C H3) 2), 1.76 (m, 2H, Ar-OCH2 -C H2 -CH2-CH3), 1.45 (m, 2H, Ar-OCH2-CH2- CH2 -CH3), 0.90 (t, 3H,, Ar-OCH2-CH2-CH2-C H3 ).

8. Method for producing liquid crystal compound of formula 1-1h

Methoxy) -2,3-difluorobenzene can be prepared by reacting 4-ethoxy-2,3-difluoro (4- (3,4-dimethylphenyl) cyclohexyl) Was prepared according to the recipe described in Scheme 3 using 4-butoxy-2,3-difluorophenol instead of phenol (13).

_{^{1 H NMR (S = CDCl 3}} , δ in ppm): 7.03 (m, 3H, Ar- H), 6.63 (m, 2H, Ar- H), 4.06 (m, 2H, OC H2 -CH3), 3.90 ( m, 2H, Ar-OC H2 -Ar), 2.72 (m, 1H, Cy-H), 2.34 (d, 6H, Ar- (C H3) 2), 1.90 (m, 5H, Cy-H), 1.72 (m, 2H, Ar-OCH2 -C H2 -CH2-CH3), 1.61 (m, 4H, Cy-H), 1.45 (m, 2H, Ar-OCH2-CH2- CH2 -CH3), 0.90 (t, 3H , Ar-OCH2-CH2-CH2-C H3 ).

The physical properties of this compound were Δε = -6.2, γ ₁ = 140, and Cr 67.6 I.

9. Method for producing liquid crystal compound of formula 1-1i

The liquid crystal compounds of 2 ', 3'-difluoro-3,4-dimethyl-4 "-propylphenyl were prepared in the following manner.

[Reaction Scheme 4]

22 30.0 (0.189 mol) and 23 35.9 g (0.158 mol) of 23 35.9 g (0.158 mol) were dissolved in toluene under a nitrogen stream, and a 2M aqueous potassium carbonate solution was added. After the temperature was raised to _{80 ℃, Pd (PPh 3)} 4 was added 9.1g (0.008mol), and refluxed overnight. After cooling, 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. Elution on silica gel column with n-heptane solution gave product 24 .

Under a nitrogen stream, 15.5 g (0.059 mol) of 24 were dissolved in anhydrous tetrahydrofuran. After cooling to -70 ° C using an ice bath, 35.7 ml of a 2.5 M concentration n-butyllithium was added dropwise. After stirring for 1 hour, 12.4 g (0.119 mol) of trimethylborate 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. To the reaction solution, a 1N aqueous hydrochloric acid solution was poured to pH 2, and the product was extracted with diethyl ether. The organic layer was washed with distilled water and dried over magnesium sulfate. heptane solution to obtain a product 25 .

Was dissolved in 1 6.1 (0.026mol) and 25 9.7g (0.031mol) in toluene in a nitrogen atmosphere, it was added potassium carbonate aqueous solution of 2M concentration. After the temperature was raised to _{80 ℃, Pd (PPh 3)} 4 was added 1.5g (0.001mol), and refluxed overnight. After cooling, 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. Elution on silica gel column with n-heptane solution gave the product 26 .

_{^{1 H NMR (S = CDCl 3}} , δ in ppm): 7.67 (m, 1H, Ar- H), 7.60 (m, 2H, Ar- H), 7.37 (d, 4H, Ar- H), 7.15 (m , 2H, Ar- H), 2.62 (t, 2H, Ar-C H2 -CH2-CH3), 2.34 (d, 6H, Ar- (C H3) 2, 1.65 (m, 2H, Ar-CH2-C H2 -CH3), 0.90 (t, 3H, Ar-CH2-CH2-C H3 ).

10. Method for producing liquid crystal compound of formula 1-1j

The liquid crystal compound of 2 ', 3'-difluoro-3,4-dimethyl-4 "-pentyltiphenyl can be obtained by using 1-pentyl- -Propylbenzene. ≪ / RTI >

_{^{1 H NMR (S = CDCl 3}} , δ in ppm): 7.67 (m, 1H, Ar- H), 7.60 (m, 2H, Ar- H), 7.37 (d, 4H, Ar- H), 7.14 (m 2H, Ar- H ), 2.62 (t, 2H, Ar-C H 2 -CH 2 -CH 2 -CH 2 -CH 3), 2.34 (d, 6H, Ar- (C H 3) 2 , 1.59 CH2-C H2 -CH2-CH2- CH3), 1.30 (m, 4H, Ar-CH2-CH2-C H2 -C H2 -CH3), 0.90 (t, 3H, Ar-CH2-CH2-CH2-CH2-C H3 ).

The physical properties of this compound were Δε = -2.0, γ ₁ = 255, and Cr 58.5 I.

Method for evaluating physical properties of liquid crystal compounds

Specifically, the physical properties of the liquid crystal compound are defined as extrapolated values obtained by substituting the measured values of the samples prepared by mixing 10% by weight of the liquid crystal compound and 90% by weight of the mother liquid crystal to be measured, In this case, the mother liquid crystal having a refractive index anisotropy (n) of 0.11, a dielectric anisotropy (?) Of -3.4 and a rotational viscosity (? ₁ ) of 130 mPa · s was used. The composition of the mother liquid crystal is shown in Table 1 below.

[Formula 1]

(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

The refractive index anisotropy (n) of the liquid crystal compound 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 (2).

[Formula 2]

n = n? - n?

 (2) Dielectric constant anisotropy of liquid crystal compound

The dielectric anisotropy (?) Of the liquid crystal compound was calculated by substituting? 3 and??

[Formula 3]

ε = 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. Then, a sample was injected into the device, and the sample was sealed with an adhesive that hardened with ultraviolet rays. Subsequently, the device was used in a 4294A instrument manufactured by Agilent, and the dielectric constant?? Of the device was measured at 20 占 폚.

(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. Subsequently, the device was used in 4294A equipment manufactured by Agilent, and the dielectric constant?? Of the device was measured at 20 ° C.

(3) Rotational viscosity of liquid crystal compound

In order to measure the rotational viscosity (? ₁ ) of the liquid crystal compound, the device was manufactured as follows. 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) Tm of liquid crystal compound

The Tm of the liquid crystal compound was obtained by placing a liquid crystal compound on a hot plate of a melting point measuring apparatus equipped with a polarizing microscope and heating the liquid crystal at a rate of 3 DEG C per minute to change the temperature when a part of the liquid crystal compound changed into a liquid crystal phase or an isotropic liquid And observed.

Evaluation of physical properties of liquid crystal compounds

Table 2 compares the physical properties of the liquid crystal compounds 1 to 3 and the conventional liquid crystal compounds 4 and 5 according to the embodiment of the present invention. Referring to Table 2, it can be seen that the liquid crystal compounds 1 to 3 according to the embodiments of the present invention have higher rotational viscosities than the conventional liquid crystal compounds 4 and 5 in dielectric anisotropy.

Property Evaluation of Liquid Crystal Composition

Table 3 shows the sign of each functional group for indicating a liquid crystal composition composed of liquid crystal compounds.

Molecular symbols used in Comparative Examples and Composition Examples

Comparative Examples and Examples conducted in the present invention are shown as follows. As can be seen from the following data, the rotational viscosity of the liquid crystal composition of Example 5 was reduced by 35% from the rotational viscosity of the liquid crystal composition of Comparative Example in the comparison of the rotational viscosities of Comparative Example and Example 5. In the remaining Examples 2 to 4, each liquid crystal composition has a dielectric anisotropy of -2.7 or less and a transparent point of 65 degrees or more, and is applicable to a display.

Comparative Example

Liquid crystal compound code Composition ratio (wt%) BB-3.4 7.7 BA-3.O2 7.7 BF-3.O2 11.5 BF-5.O2 11.5 AF-3.O2 11.5 BAA-5.2 7.6 BAA-3.2 7 BBF-3.O2 8 BBF-3.O4 8 BBF-5.O2 8 BBF-3.1 7.7 BCAB-3.3 3.8 Clear point (Tni, ℃) 91.4 Refractive index anisotropy (? N) 0.1144 The dielectric anisotropy (DELTA epsilon) -4.1 The rotational viscosity (? 1, mPa? S) 200

Example 1

Liquid crystal compound code Composition ratio (wt%) BB-3.4 7.9 BA-3.O2 6.7 BA-5.O2 7.9 AF-3.O2 9.3 BAA-3.2 6.4 BBF-2.1 14.4 BBF-3.1 14 BAF-3.O2 9.3 ZOOM-1.O2 5.5 ZBYF-1.O2 9.3 ZBYF-1.O4 9.3 Clear point (Tni, ℃) 69.3 Refractive index anisotropy (? N) 0.1149 The dielectric anisotropy (DELTA epsilon) -3.4 The rotational viscosity (? 1, mPa? S) 148

Example 2

Liquid crystal compound code Composition ratio (wt%) BB-3.4 7.9 BA-3.O2 7 BA-5.O2 7 AF-3.O2 10.7 BAA-3.2 6.4 BBF-2.1 14 BBF-3.1 14 BAF-3.O2 15 ZOOM-1.O2 6 ZBYF-1.O4 6 ZF-1.O4 6 Clear point (Tni, ℃) 71.9 Refractive index anisotropy (? N) 0.1225 The dielectric anisotropy (DELTA epsilon) -3.2 The rotational viscosity (? 1, mPa? S) 136

Example 3

Liquid crystal compound code Composition ratio (wt%) BB-3.4 11.1 BA-3.O1 6 BA-3.O2 6 BA-5.O2 6 AF-3.O2 12.9 BAA-3.2 5.5 BBF-2.1 12 BBF-3.1 12 BAF-3.O2 12.9 ZOOM-1.O2 5.2 ZBYF-1.O2 0 ZBYF-1.O4 5.2 ZFA-1.5 5.2 Clear point (Tni, ℃) 71.0 Refractive index anisotropy (? N) 0.1217 The dielectric anisotropy (DELTA epsilon) -2.7 The rotational viscosity (? 1, mPa? S) 126

Example 4

Liquid crystal compound code Composition ratio (wt%) BB-3.4 9.1 BA-3.O2 5 BA-5.O2 5 AF-3.O2 15.1 BAA-3.2 4.6 BBF-2.1 10 BBF-3.1 10 BAF-3.O2 10.8 BCAB-3.3 8.4 ZBYF-1.O2 4.4 ZBYF-1.O4 4.4 ZF-1.O2 4.4 ZF-3.O2 4.4 ZFA-1.5 4.4 Clear point (Tni, ℃) 72.6 Refractive index anisotropy (? N) 0.1248 The dielectric anisotropy (DELTA epsilon) -2.9 The rotational viscosity (? 1, mPa? S) 131

Example 5

Liquid crystal compound code Composition ratio (wt%) BB-3.4 10.4 BA-5.O2 5.7 AF-3.O2 22.9 BAA-3.2 5.3 AFA-2.3 11.4 BBF-2.1 11.4 BAF-3.O2 22.9 ZBYF-1.O2 5 ZBYF-1.O4 5 Clear point (Tni, ℃) 77.3 Refractive index anisotropy (? N) 0.1472 The dielectric anisotropy (DELTA epsilon) -4.0 The rotational viscosity (? 1, mPa? S) 130

Claims (17)

A first substrate;
A second substrate facing the first substrate; And
And a liquid crystal layer provided between the first substrate and the second substrate and made of a liquid crystal composition,
Wherein the liquid crystal layer comprises a liquid crystal compound represented by the following formula (1).
[Chemical Formula 1]

R ¹ is hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is substituted with -C≡C-, -CH═CH- , -CF ₂ O-, -O-, -COO-, -OCO- or -OCO-O-, or at least one H may be replaced by halogen,
A ¹ and A ² are each independently selected from the group consisting of cyclohexylene, phenylene, tetrahydropyranylene, dioxanylene, cyclohexenylene, 1,4-bicyclopentadiene, Cyclic [2.2.2] octylene, pyridinylene, naphthylene, tetrahydronaphthylene, or decalinylene. In either case, one or more H may be replaced by halogen,
Z ¹ , Z ² and Z ³ are each independently a single bond, -CH ₂ CH ₂ -, -CH═CH-, -C≡C-, -CH ₂ O-, -OCH ₂ -, -CH ₂ CF ₂ -, -CHFCHF-, -CF ₂ CH ₂ -, -CH ₂ CHF-, -CHFCH ₂ -, -C ₂ F ₄ -, -COO-, -OCO-, -CF ₂ O-, -OCF ₂ - or -O-,
L ¹ and L ² are each independently hydrogen, halogen, trifluoromethyl or cyano,
n and m are each independently 0, 1 or 2; The method according to claim 1,
And R &^lt; 1 > is alkoxy having 1 to 5 carbon atoms. The method according to claim 1,
L ¹ and L ² are fluorine, and Z ¹ , Z ² and Z ³ are each independently a single bond, -CH ₂ O- or -OCH ₂ -. A liquid crystal composition comprising a liquid crystal compound represented by the following formula (1)
[Chemical Formula 1]

One
R ¹ is hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is substituted with -C≡C-, -CH═CH- , -CF ₂ O-, -O-, -COO-, -OCO- or -OCO-O-, or at least one H may be replaced by halogen,
A ¹ and A ² are each independently selected from the group consisting of cyclohexylene, phenylene, tetrahydropyranylene, dioxanylene, cyclohexenylene, 1,4-bicyclopentadiene, Cyclic [2.2.2] octylene, pyridinylene, naphthylene, tetrahydronaphthylene, or decalinylene. In either case, one or more H may be replaced by halogen,
Z ¹ , Z ² and Z ³ are each independently a single bond, -CH ₂ CH ₂ -, -CH═CH-, -C≡C-, -CH ₂ O-, -OCH ₂ -, -CH ₂ CF ₂ -, -CHFCHF-, -CF ₂ CH ₂ -, -CH ₂ CHF-, -CHFCH ₂ -, -C ₂ F ₄ -, -COO-, -OCO-, -CF ₂ O-, -OCF ₂ - or -O-,
L ¹ and L ² are each independently hydrogen, halogen, trifluoromethyl or cyano,
n and m are each independently 0, 1 or 2; 5. The method of claim 4,
And R &^lt; 1 > is alkoxy of 1 to 5 carbon atoms. 5. The method of claim 4,
L ¹ and L ² are fluorine, and Z ¹ , Z ² and Z ³ are each independently a single bond, -CH ₂ O- or -OCH ₂ -. 5. The method of claim 4,
The liquid crystal compound of Formula 1 is represented by Formula 1-1.
[Formula 1-1]

R ₁ , A ₁ , Z ₁ , Z ₂ , L ₁ , and L ₂ are the same as defined in formula (1). 8. The method of claim 7,
The liquid crystal compound represented by Formula 1-1 is selected from the group consisting of Formulas 1-1a to 1-1j.
[Formula 1-1a]

[Formula 1-1b]

[Formula 1-1c]

[Chemical Formula (1-1d)

[Formula 1-1e]

[Formula 1-1f]

[Chemical Formula 1-1g]

[Formula 1-1h]

[Formula 1-1i]

[Chemical Formula (1-1j)

5. The method of claim 4,
Wherein the liquid crystal compound represented by Formula 1 is contained in an amount of 1 to 60 wt% based on the total weight of the liquid crystal composition. The liquid crystal composition according to claim 4, further comprising at least one liquid crystal compound selected from the group consisting of the following formulas (2) to (5):
(2)
R ¹¹ -A ³ -A ⁴ -R ¹²
In Formula 2, R ¹¹ and R ¹² are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is not directly connected to oxygen atoms is _{-C≡C-, -CH = CH-, -CF 2} O-, -O-, -COO- or -OCO-, or substituted or one or more of the H may be replaced by halogen,
A ³ and A ⁴ are each independently cyclohexylene or phenylene,
(3)
R ¹³ -A ⁵ - (A ⁶ ) _p -A ⁷ -R ¹⁴
In Formula 3, R ¹³ and R ¹⁴ are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is not directly connected to oxygen atoms is _{-C≡C-, -CH = CH-, -CF 2} O-, -O-, -COO- or -OCO-, or substituted or one or more of the H may be replaced by halogen,
A ⁵ and A ⁷ are each independently cyclohexylene or phenylene,
A ⁶ is phenylene substituted with cyclohexylene, phenylene or halogen,
p is an integer of 1 or 2,
[Chemical Formula 4]

In Formula 4, R ¹⁵ and R ¹⁶ are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is not directly bonded to oxygen atoms is _{-C≡C-, -CH = CH-, -CF 2} O-, -O-, -COO- or -OCO-, or substituted or one or more of the H may be replaced by halogen,
A ⁸ and A ⁹ are each independently phenylene substituted with cyclohexylene, tetrahydropyranylene, phenylene or halogen,
q is an integer between 0 and 2,
[Chemical Formula 5]

Wherein R ¹⁷ and R ¹⁸ are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is not directly connected to oxygen atoms, -C≡C-, -CH═CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above H may be replaced by halogen,
A ¹⁰ , A ¹¹ and A ¹² are each independently any one of cyclohexylene, tetrahydropyranylene, phenylene and phenylene substituted with halogen,
Z ⁴ and Z ⁵ are each independently _{-CH 2 CH 2 -, -CH =} CH-, -C≡C-, -CH 2 O-, -OCH 2 -, -CH 2 CF 2 -, -CHFCHF-, -CF ₂ CH ₂ -, -CH ₂ CHF-, -CHFCH ₂ -, -C ₂ F ₄ -, -COO-, -OCO-, -CF ₂ O-, -OCF ₂ - or -O-,
r and v are integers between 0 and 1, r + v is 1 or 2,
s and w are integers between 0 and 2; 5. The method of claim 4,
A liquid crystal composition further comprising an antioxidant selected from the group consisting of compounds represented by the following formulas (6) and (7):
[Chemical Formula 6]

(7)

In the formulas (6) and (7), R ¹⁹ and R ²⁰ are each independently hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - -CH = CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above H may be replaced by halogen,
A ¹³ is cyclohexylene, tetrahydropyranylene, or dioxanylene. 5. The method of claim 4,
A liquid crystal composition further comprising a UV stabilizer selected from the group consisting of compounds represented by the following formulas (8) to (10).
[Chemical Formula 8]

Wherein R ²¹ is hydrogen, oxygen, alkyl of 1 to 15 carbon atoms or alkoxy of 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is -C≡C -, -CH = CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above may be replaced by halogen,
[Chemical Formula 9]

Wherein R ²² and R ²³ are each independently hydrogen, oxygen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is bonded directly to oxygen atoms -CH = CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above H may be replaced by halogen,
f is an integer of 0 to 12,
[Chemical formula 10]

In Formula 10, R ²⁴ is hydrogen, oxygen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is -C≡C- , -CH = CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or at least one of the above may be replaced by halogen,
j is an integer of 0 to 12; A liquid crystal compound represented by the following formula (1).
[Chemical Formula 1]

R ¹ is hydrogen, alkyl having 1 to 15 carbon atoms or alkoxy having 1 to 15 carbon atoms, and at least one -CH ₂ - of the alkyl or alkoxy is substituted with -C≡C-, -CH═CH- , -CF ₂ O-, -O-, -COO-, -OCO- or -OCO-O-, or at least one H may be replaced by halogen,
A ¹ and A ² are each independently selected from the group consisting of cyclohexylene, phenylene, tetrahydropyranylene, dioxanylene, cyclohexenylene, 1,4-bicyclopentadiene, Cyclic [2.2.2] octylene, pyridinylene, naphthylene, tetrahydronaphthylene, or decalinylene. In either case, one or more H may be replaced by halogen,
Z ¹ , Z ² and Z ³ are each independently a single bond, -CH ₂ CH ₂ -, -CH═CH-, -C≡C-, -CH ₂ O-, -OCH ₂ -, -CH ₂ CF ₂ -, -CHFCHF-, -CF ₂ CH ₂ -, -CH ₂ CHF-, -CHFCH ₂ -, -C ₂ F ₄ -, -COO-, -OCO-, -CF ₂ O-, -OCF ₂ - or -O-,
L ¹ and L ² are each independently hydrogen, halogen, trifluoromethyl or cyano,
n and m are each independently 0, 1 or 2; 14. The method of claim 13,
R &^lt; 1 > is an alkoxy of 1 to 5 carbon atoms, 14. The method of claim 13,
L ¹ and L ² are fluorine, and Z ¹ , Z ² and Z ³ are each independently a single bond, -CH ₂ O- or -OCH ₂ -. 14. The method of claim 13,
The liquid crystal compound of Formula 1 is a liquid crystal compound represented by Formula 1-1
[Formula 1-1]

R ₁ , A ₁ , Z ₁ , Z ₂ , L ₁ , and L ₂ are the same as defined in formula (1). 17. The method of claim 16,
The liquid crystal compound represented by Formula 1-1 is selected from the group consisting of Formulas 1-1a to 1-1j.
[Formula 1-1a]

[Formula 1-1b]

[Formula 1-1c]

[Chemical Formula (1-1d)

[Formula 1-1e]

[Formula 1-1f]

[Chemical Formula 1-1g]

[Formula 1-1h]

[Formula 1-1i]

[Chemical Formula (1-1j)

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