KR102509600B1 - 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 containing the liquid crystal compound, and a liquid crystal display device containing the liquid crystal composition. The liquid crystal compound has a xylene group.

Description

A liquid crystal compound, a liquid crystal composition containing the liquid crystal compound, and a liquid crystal display device containing the liquid crystal composition

The present invention relates to a liquid crystal compound, a liquid crystal composition containing the liquid crystal compound, and a liquid crystal display device containing the liquid crystal composition, and specifically, a liquid crystal compound containing a xylene group, a liquid crystal composition containing the liquid crystal compound, and It relates to a liquid crystal display device including the liquid crystal composition.

A single liquid crystal compound constituting the liquid crystal preparation is an organic material having a molecular weight of about 200 to 600 g/mol and has a long rod-shaped molecular structure. The liquid crystal molecular structure is divided into a core group that maintains straightness, a terminal group that has flexibility, and a linkage group for a specific purpose. The terminal part consists of a chain form (alkyl, alkoxy, alkenyl, etc.) that is easy to bend on one or both sides to maintain flexibility, and the other side or the side of the central group introduces a polar group (F, CN, OCF ₃ , etc.) to improve dielectric constant. It plays a role in controlling the physical properties of liquid crystals such as

In liquid crystal display (LCD), there are many types such as TN (Twist nematic), IPS (In-plane switching), FFS (Fringe field switching), VA (Vertical alignment) depending on the characteristics and application mode of the LCD panel. do. In such a variety of liquid crystal display devices, it is impossible to meet all the required characteristics of the product, such as the temperature of the clearing point, dielectric anisotropy, refractive index anisotropy, and rotational viscosity, with one or two liquid crystal compounds, and usually 7 to 20 single liquid crystal compounds A liquid crystal composition is prepared by mixing.

A liquid crystal compound according to an embodiment of the present invention is represented by Chemical Formula 1 below.

[Formula 1]

R ¹ is hydrogen, 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- such that oxygen atoms are not directly connected. , -CF ₂ O-, -O-, -COO-, -OCO- or -OCO-O-, or one or more H may be replaced by halogen,

A ¹ and A ² are each independently cyclohexylene, phenylene, tetrahydropyranylene, dioxanylene, cyclohexenylene, 1,4-bi Among cyclo[2.2.2]octylene (1,4-bicyclo[2.2.2]octylene), pyridinylene, naphthylene, tetrahydronaphthylene or decalinylene As either, one or more H may be replaced with 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.

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

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

[Formula 1-1]

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

[Formula 1-1a]

[Formula 1-1b]

[Formula 1-1c]

[Formula 1-1d]

[Formula 1-1e]

[Formula 1-1f]

[Formula 1-1g]

[Formula 1-1h]

[Formula 1-1i]

[Formula 1-1j]

A liquid crystal composition according to an embodiment of the present invention includes the liquid crystal compound represented by Formula 1 above.

According to an embodiment of the present invention, the liquid crystal composition may include the liquid crystal compound represented by Chemical Formula 1 in an amount of 1 to 60% by weight 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 one or more liquid crystal compounds selected from the group consisting of Chemical Formulas 2 to 5 below. [Formula 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 one or more of the H may be replaced by halogen;

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

[Formula 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 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 cyclohexylene, phenylene or phenylene substituted with halogen;

p is an integer of 1 or 2;

[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 connected to oxygen atoms. -C≡C-, -CH=CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or one or more of the H may be replaced by halogen;

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

q is an integer between 0 and 2;

[Formula 5]

In Formula 5, 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 one or more of the H may be replaced by halogen;

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

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 Chemical Formulas 6 and 7.

[Formula 6]

[Formula 7]

In Chemical 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 - of the alkyl or alkoxy group is directly connected to an oxygen atom. -C≡C-, -CH=CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or one or more of the 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 Formulas 8 to 10 below.

[Formula 8]

In Formula 8, R ²¹ is hydrogen, oxygen, alkyl having 1 to 15 carbon atoms, or alkoxy having 1 to 15 carbon atoms, and one or more -CH ₂ - of the alkyl or alkoxy group is -C≡C such that oxygen atoms are not directly connected. -, -CH=CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or one or more of the H may be replaced by halogen,

[Formula 9]

In Formula 9, 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 directly connected to the oxygen atom. -C≡C-, -CH=CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or one or more of the H may be replaced by halogen,

f is an integer from 0 to 12;

[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 one or more -CH ₂ - of the alkyl or alkoxy group is -C≡C- so that oxygen atoms are not directly connected. , -CH=CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or one or more of the H may be replaced by halogen,

j is an integer from 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.

A liquid crystal compound and a liquid crystal composition including the liquid crystal compound according to embodiments of the present invention exhibit high refractive index anisotropy and high resistivity under low rotational viscosity. The liquid crystal compound and the liquid crystal composition including the liquid crystal compound may be employed in various liquid crystal display devices, and the liquid crystal display device employing the liquid crystal compound and the liquid crystal composition including the liquid crystal compound has a fast response time.

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

Since the present invention may have various changes and various forms, specific embodiments are illustrated in the drawings and described in detail in the text. However, it should be understood that this is not intended to limit the present invention to the specific disclosed form, and includes all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

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

According to an embodiment of the present invention, a liquid crystal compound represented by Chemical Formula 1 is provided.

[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 -CH ₂ - of at least one of the alkyl or alkoxy is -C≡C-, -CH=CH- so that oxygen atoms are not directly connected. , -CF ₂ O-, -O-, -COO-, -OCO- or -OCO-O-, or one or more H may be replaced with a halogen.

A ¹ and A ² are each independently cyclohexylene, phenylene, tetrahydropyranylene, dioxanylene, cyclohexenylene, 1,4-bi Among cyclo[2.2.2]octylene (1,4-bicyclo[2.2.2]octylene), pyridinylene, naphthylene, tetrahydronaphthylene or decalinylene As either, one or more H may be replaced with 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 It is -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 the present specification, the following terms may be defined as follows unless otherwise specified.

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

Alkyl of 1 to 15 carbon atoms may be straight chain, branched chain or cyclic. Specifically, alkyl having 1 to 15 carbon atoms is a straight-chain alkyl having 1 to 10 carbon atoms; straight-chain alkyl of 1 to 5 carbon atoms; branched or cyclic alkyl having 3 to 10 carbon atoms; Or it may be a branched or cyclic alkyl having 3 to 5 carbon atoms. More specifically, alkyl having 1 to 15 carbon atoms may be methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, tert-butyl, n-pentyl, iso-pentyl, or cyclohexyl.

Alkoxy having 1 to 15 carbon atoms may be straight chain, branched chain or cyclic alkoxy. Specifically, the alkoxy having 1 to 15 carbon atoms is straight-chain alkoxy having 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 it may be a branched or cyclic alkoxy having 3 to 5 carbon atoms. More specifically, alkoxy having 1 to 15 carbon atoms is methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, iso-butoxy, tert-butoxy, n-pentoxy, iso-phen oxy or cyclohexoxy, and the like.

And, in an alkyl or alkoxy having 1 to 15 carbon atoms, one or more -CH ₂ - is -C≡C-, -CH=CH-, -CF ₂ O-, -O-, -COO-, -OCO- or -OCO -O- may be substituted with . For example, methyl may be replaced by vinyl (-CH=CH-H) in which -CH ₂ - of methyl (-CH ₂ -H) is substituted with -CH=CH-. However, one or more -CH ₂ - of the above may be substituted with the above-mentioned substituents so that oxygen atoms are not directly connected.

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

A single bond means a case in which no separate atom exists in the part represented by Z ¹ to Z ⁵ . For example, in Formula 1, when Z ¹ is a single bond and n and m are 0, the xylene ring may be directly connected to the benzene ring to form a structure.

The liquid crystal compound of Chemical Formula 1 may exhibit a significantly reduced viscosity compared to conventional liquid crystal compounds while maintaining high dielectric constant anisotropy and refractive index anisotropy by including a xylene group. In particular, the liquid crystal compound of Chemical Formula 1 may exhibit excellent physical properties while exhibiting a significantly reduced viscosity compared to conventional liquid crystal compounds containing a 4-alkylcyclohexyl group. Therefore, when the liquid crystal compound of Chemical Formula 1 is used, a liquid crystal display device capable of excellent physical properties and high-speed response can be provided.

In addition, the liquid crystal compound of Chemical Formula 1 has a polar functional group on the side of the central group and exhibits negative dielectric constant anisotropy. Accordingly, when the liquid crystal compound of Chemical Formula 1 is used, VA (Virtical Alignment), MVA (Multidomain Virtical Alignment), PVA (Patterned Virtical Alignment), PS-VA (Polymer Stabilized Virtical Alignment) or IPS using a negative liquid crystal material (In-Plane Switching) mode and the like are expected to be able to realize high-speed response of liquid crystal display elements.

The liquid crystal compound of Chemical Formula 1 has the following structure, and may exhibit low viscosity along with better physical properties.

Specifically, a liquid crystal compound in which R ¹ of Formula 1 is an alkoxy having 1 to 5 carbon atoms may exhibit higher dielectric constant anisotropy and lower viscosity.

In addition, a liquid crystal compound in which A ¹ and A ² of Formula 1 are each independently any one of cyclohexylene, phenylene, and phenylene substituted with halogen can be driven at a low voltage and sufficiently It can exhibit low-temperature stability, high dielectric constant anisotropy, and high refractive index anisotropy.

In addition, a liquid crystal compound in which L ¹ and L ² of Chemical Formula 1 each independently represent any one of halogen and trifluoromethyl may exhibit high negative dielectric constant anisotropy.

Meanwhile, Z ¹ , Z ² , and Z ³ connecting the central groups in Formula 1 may be appropriately selected from the above-described substituents according to the use of the liquid crystal compound. For 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 Chemical Formula 1 may be a liquid crystal compound represented by Chemical Formula 1-1 below.

[Formula 1-1]

R ₁ , A ₁ , Z ₁ , Z ₂ , L ₁ , and L ₂ have the same definitions as in Formula 1.

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

[Formula 1-1a]

[Formula 1-1b]

[Formula 1-1c]

[Formula 1-1d]

[Formula 1-1e]

[Formula 1-1f]

[Formula 1-1g]

[Formula 1-1h]

[Formula 1-1i]

[Formula 1-1j]

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

The liquid crystal composition includes at least one liquid crystal compound represented by Chemical Formula 1. The liquid crystal composition may include at least one liquid crystal compound represented by Chemical 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 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 one or more liquid crystal compounds represented by Chemical 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 Chemical Formula 1 exceeds the above range, the phase transition temperature of the liquid crystal composition is greatly increased, which may cause a problem that a liquid crystal phase cannot be secured in a low temperature region.

In addition to the liquid crystal compound of Chemical Formula 1, the liquid crystal composition may further include various liquid crystal compounds for various performances of the liquid crystal display device.

For example, the liquid crystal composition may further include a known low-viscosity liquid crystal compound. As such a low-viscosity liquid crystal compound, a liquid crystal compound represented by the following formula (2) and the like can be used.

[Formula 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 one or more of the H may be replaced with a halogen.

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

The liquid crystal compound represented by Chemical Formula 2 may be at least one liquid crystal compound selected from the group consisting of compounds represented by Chemical Formulas 2-1 and 2-2 below. The liquid crystal compounds represented by Chemical Formula 2-1 and Chemical Formula 2-2 may be used to easily adjust the clearing point, rotational viscosity, refractive index anisotropy, and dielectric constant anisotropy of the liquid crystal composition while maintaining high resistivity.

[Formula 2-1]

[Formula 2-2]

In Formulas 2-1 and 2-2, R ¹¹ and R ¹² may be defined as R ¹¹ and R ¹² in Formula 2.

In one embodiment of the present invention, the content of the component of Formula 2 may be used in an amount of about 5% to about 40% by weight, and when it exceeds about 40% by weight, it is difficult to control the dielectric constant anisotropy or the low-temperature stability of the liquid crystal composition this gets worse In addition, when less than about 5% by weight is used, the effect of low viscosity is reduced.

As another example, the liquid crystal composition may further include a known 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 Chemical Formula 3 and the like may be used.

[Formula 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 one or more of the H may be replaced with a halogen.

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

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

p is an integer of 1 or 2;

The liquid crystal compound represented by Chemical Formula 3 may be at least one liquid crystal compound selected from the group consisting of Chemical Formulas 3-1 to 3-5. The liquid crystal compounds represented by Chemical Formulas 3-1 and 3-5 may be used to easily adjust the clearing point, rotational viscosity, refractive index anisotropy and dielectric constant anisotropy of the liquid crystal composition while maintaining high resistivity.

[Formula 3-1]

[Formula 3-2]

[Formula 3-3]

[Formula 3-4]

[Formula 3-5]

In Chemical Formulas 3-1 to 3-5, R ¹³ and R ¹⁴ may be defined as R ¹³ and R ¹⁴ in Chemical Formula 3.

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

As another example, the liquid crystal composition may further include a known medium dielectric constant liquid crystal compound. As such a liquid crystal compound with a medium dielectric constant, a liquid crystal compound represented by the following Chemical Formula 4 may be used.

[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 connected to oxygen atoms. -C≡C-, -CH=CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or one or more of the H may be replaced with a halogen.

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

q is an integer between 0 and 2;

The liquid crystal compound represented by Chemical Formula 4 may be at least one liquid crystal compound selected from the group consisting of Chemical Formulas 4-1 to 4-4 below. The liquid crystal compounds represented by Chemical Formulas 4-1 and 4-4 may be used to easily adjust the clearing point, rotational viscosity, refractive index anisotropy and dielectric constant anisotropy of the liquid crystal composition while maintaining high resistivity.

[Formula 4-1]

[Formula 4-2]

[Formula 4-3]

[Formula 4-4]

In Chemical Formulas 4-1 to 4-4, R ¹⁵ and R ¹⁶ may be defined as R ¹⁵ and R ¹⁶ in Chemical Formula 4.

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

As another example, the liquid crystal composition may further include a known high dielectric constant liquid crystal compound. As such a liquid crystal compound, a liquid crystal compound represented by Chemical Formula 5 or the like may be used.

[Formula 5]

In Formula 5, 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 one or more of the H may be replaced with a halogen.

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

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 Chemical Formula 5 may be at least one liquid crystal compound selected from the group consisting of Chemical Formulas 5-1 to 5-4. The liquid crystal compounds represented by Chemical Formulas 5-1 and 5-4 may be used to easily adjust the clearing point, rotational viscosity, refractive index anisotropy, and dielectric constant anisotropy of the liquid crystal composition while maintaining high resistivity.

[Formula 5-1]

[Formula 5-2]

[Formula 5-3]

[Formula 5-4]

In Chemical Formulas 5-1 to 5-4, R ¹⁷ and R ¹⁸ may be defined as R ¹⁷ and R ¹⁸ in Chemical Formula 5.

In one embodiment of the present invention, the liquid crystal compound represented by Chemical Formula 5 may be included in an amount of 0% to about 30% by weight in the liquid crystal composition. The liquid crystal compound represented by Chemical Formula 5 is necessary for realizing a high dielectric constant liquid crystal composition, and when it exceeds 30% by weight, reliability of a display such as voltage holding ratio (VHR) may be deteriorated.

The liquid crystal composition may appropriately include one or more liquid crystal compounds among the liquid crystal compounds represented by Chemical Formulas 2 to 5 in consideration of desired uses and effects of the liquid crystal composition. In particular, the liquid crystal composition may include liquid crystal compounds represented by Chemical Formulas 2, 3, and 4 in order to improve various physical properties of the liquid crystal composition in a balanced manner. In this case, as the liquid crystal compounds represented by Chemical Formulas 2 to 4, one or more liquid crystal compounds may be used.

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

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).

[Formula 6]

[Formula 7]

In Chemical 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 - of the alkyl or alkoxy group is directly connected to an oxygen atom. -C≡C-, -CH=CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or one or more of the H may be replaced with a halogen.

A ¹³ is cyclohexylene, tetrahydropyranylene or dioxanylene.

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

[Formula 8]

In Formula 8, R ²¹ 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 -C≡C- so that oxygen atoms are not directly connected. -CH=CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or one or more of the H may be replaced with a halogen.

[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 one or more of the H may be replaced with a halogen.

f is an integer from 0 to 12;

[Formula 10]

In Formula 10, R ²⁴ 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 -C≡C-, - so that oxygen atoms are not directly connected. CH=CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or one or more of the H may be replaced with a halogen.

j is an integer from 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 the UV stabilizer is contained in the liquid crystal composition in an amount exceeding 2,000 ppm, the physical properties of the liquid crystal composition, in particular, the clearing point may decrease significantly. In addition, in the case of additives with a high melting point, low-temperature stability is also adversely affected. Therefore, it is appropriate that the additive is contained at 2,000 ppm or less. In addition, in a liquid crystal composition having a dielectric constant anisotropy of 0 to -4.0, it 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 drawings as follows.

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

Referring to FIG. 1 , a liquid crystal display device according to an exemplary 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 (eg, a row direction) and a second direction D2 crossing the first direction D1 (eg, a row direction). For example, a plurality of data lines DL1 to DLn extending in a 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 control signals from an external graphic controller (not shown). The control signals include a vertical synchronization signal (Vsync) as a frame discrimination signal, a horizontal synchronization signal (Hsync) as a row discrimination signal, and a data enable data having a high level only during a period in which data is output to indicate an area where data is received. signal DES and a main clock signal MCLK.

The timing controller TC converts the image data RGB to meet the specifications 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 may include a scan start signal for instructing a scan start, at least one clock signal for controlling an output cycle of the gate-on voltage, and an output enable signal for limiting the duration of the gate-on voltage. can

The data driver DDV generates a grayscale voltage according to the image data DATA based on the data control signal DS1 and outputs the grayscale voltage as a data voltage to the data lines DL1 to DLn. The data voltage may include a positive data voltage having a positive value and a negative data voltage having a negative value with respect to the common voltage. The data control signal DS1 is a horizontal start signal STH indicating the start of transmission of the image data DATA to the data driver DDV and a load requesting application of data voltages to the data lines DL1 to DLn. signal, and an inversion signal for inverting the polarity of the data voltage with respect to the common voltage.

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 or a flexible printed circuit board. It may be mounted on a printed circuit board and attached to the display panel PNL in the form of a tape carrier package (TCP), or mounted on a separate printed circuit board. Unlike this, at least one of the gate driver GDV and the data driver DDV is the display panel PNL together with the gate lines GL1 to GLm, the data lines DL1 to DLn, and the transistor. ) may be integrated. 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 illustrating the pixel shown in FIG. 1 , and FIG. 3 is a cross-sectional view taken along line II′ of FIG. 2 .

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 displaying images. In FIG. 2 , one of a plurality of pixels is representatively shown. Since the remaining pixels have substantially the same structure as the structure shown above, they are not separately illustrated.

The pixel PX is provided between data lines sequentially arranged in the first direction D1 and between gate lines adjacent to each other. In this embodiment, for convenience of description, a gate line connected to one pixel will be referred to as a gate line GL, and a data line connected to the pixel will be referred to as a first data line DL.

The liquid crystal display device 10 according to an exemplary 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 a first alignment layer AL1. ).

The first base substrate 110 has a pixel area PA provided with each pixel. The pixel area PA has a rectangular shape elongated in one direction, but is not limited thereto. The shape of the pixel area PA may be variously deformed, such as a V shape or a Z shape.

A gate line GL, a data line DL, a thin film transistor TFT, and a pixel electrode PE are provided in the pixel area PA.

The gate line GL extends in one direction on the first base substrate 110 and is provided. The data line DL is provided on the first base substrate 110 to cross and be insulated from the gate line 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 has a gate electrode GE branched from the gate line GL, a source electrode SE branched from the data line DL, and a drain electrode DE spaced apart 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 area PA on the first base substrate 110 .

A semiconductor pattern SM is provided on the gate line GL with a first insulating layer 111 interposed 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 provided on the first insulating layer 111 on which the source electrode SE and the drain electrode DE are formed. A passivation layer 115 is provided on the second insulating layer. The pixel electrode PE is provided on the passivation layer 115 , and electrical contact with the drain electrode DE is provided through a contact hole CH formed through the second insulating layer 113 and the passivation layer 115 . connected to

A first alignment layer AL1 is provided on the pixel electrode PE. The first alignment layer AL1 is for pretilting the liquid crystal molecules and 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.

The second substrate 200 is provided to face 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 provided on the color filters CF and the black matrix BM.

The color filters CF are provided to correspond to the pixel areas PA. Each color filter CF implements one color among red, green, and 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 one embodiment of the present invention, although it is shown that the color filter CF is provided in the second substrate 200, it is not limited thereto, and in another embodiment, it 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 is for pretilting the liquid crystal molecules and may be formed of a compound including a polymer selected from the group consisting of polyamic acid, polyimide, and combinations thereof, and an epoxy crosslinking agent.

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 transmitted through the turned on thin film transistor TFT. It is provided as the pixel electrode PE. Accordingly, an electric field is formed between the pixel electrode PE and the common electrode CE to which the common voltage is applied. 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 passing through the liquid crystal layer 300 .

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

In this embodiment, although disclosed for the most basic type of liquid crystal display, it is not limited thereto, and can be applied to other modes of liquid crystal display requiring a fast response time, of course. For example, in one embodiment of the present invention, the pixel electrode and the common electrode are formed as a whole plate, but in another embodiment, at least one of the pixel electrode and the common electrode has a shape other than a plate, for example, a slit or a protrusion. The pattern may have an added shape. In addition, in one embodiment of the present invention, it is shown that the pixel electrode and the common electrode are formed on different substrates, but in another embodiment of the present invention, the pixel electrode or the common electrode is formed on one substrate, for example, It may be provided on the first substrate. Accordingly, the liquid crystal composition can be employed in liquid crystal display devices of various modes such as VA (vertical alignment) mode, FFS (fringe field switching) mode, IPS (in plane switching) mode, and PLS (plane to light switching) mode. there is.

In particular, since the liquid crystal composition according to an embodiment of the present invention exhibits high negative dielectric constant anisotropy and high refractive index anisotropy even under low rotational viscosity, VA, MVA (Multidomain Virtical Alignment), PVA ( patterned virtual alignment), polymer stabilized virtual alignment (PS-VA), and the like.

Hereinafter, the action and effect of the invention will be described in more detail through specific examples of the invention. However, this is presented as an example of the invention, and thereby the scope of the invention is not limited in any sense.

1. Method for preparing a liquid crystal compound of Chemical Formula 1-1a

A liquid crystal compound of 4-ethoxy-2,3-difluoro-3”,4”-dimethylterphenyl was prepared by the following method.

[Scheme 1]

30.0 g (0.129 mol) of 1 was dissolved in anhydrous tetrahydrofuran under a nitrogen stream. After cooling to -70°C using an ice bath, 77.5 ml of 2.5M n-butyllithium was added dropwise. After stirring for 1 hour, 28.8 g (0.258 mol) of trimethyl borate 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. 1N hydrochloric acid aqueous solution was poured into the reaction solution to pH 2, and the product was extracted with diethyl ether. The organic layer was washed with distilled water and dried over magnesium sulfate. Recrystallization from n-heptane solution gave product 2 .

After dissolving 46.9g (0.166mol) of 3 and 30.4g (0.151mol) of 4 in toluene under a nitrogen stream, a 2M aqueous solution of potassium carbonate was added. After raising the temperature to 60°C, 8.7 g (0.008 mol) of Pd(PPh ₃ ) ₄ was added 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. Product 5 was obtained by eluting on a silica gel column with n-heptane:ethyl acetate=10:1 solution.

After dissolving 2 20.0g (0.148mol) and 5 38.6g (0.123mol) in toluene under a nitrogen stream, a 2M aqueous solution of potassium carbonate was added. After raising the temperature to 80°C, 9.2 g (0.008 mol) of Pd(PPh ₃ ) ₄ was added 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 a silica gel column with n-heptane solution gave product 6 .

^1H 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, OCH2 -CH3), 2.34 (m, 6H, Ar-( CH3)2 ), 1.32 (t, 3H, CH2- CH3 ).

2. Method for preparing the liquid crystal compound of Chemical Formula 1-1b

4-ethoxy-2,3,3'-trifluoro-3”,4”-dimethylterphenyl compound is 1-bromo-4-iodobenzene (3) in Scheme 1 It was prepared according to the preparation method of Scheme 1 using -2-fluoro-4-iodobenzene.

^1H 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 preparing the liquid crystal compound of Chemical Formula 1-1c

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

[Scheme 2]

After dissolving 2 20.0g (0.133mol) and 3 31.3g (0.111mol) in toluene under a nitrogen stream, a 2M aqueous solution of potassium carbonate was added. After raising the temperature to 60°C, 7.7 g (0.007 mol) of Pd(PPh ₃ ) ₄ was added 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 a silica gel column with n-heptane solution gave product 7 .

25.0 g (0.095 mol) of 7 was dissolved in anhydrous tetrahydrofuran under a nitrogen stream. After cooling to -70°C using an ice bath, 45.9 ml of 2.5M 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 anhydrous tetrahydrofuran solution containing an excess amount of dry ice. The resulting solid was separated to give product 8 .

19.7 g (0.093 mol) of 8 was dissolved in anhydrous tetrahydrofuran under a nitrogen stream. After cooling to -30°C using an ice bath, 70.0 ml of 2M boranedimethylsulfide was added dropwise. 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 a silica gel column with n-heptane solution gave product 9 .

16.3 g (0.076 mol) of 9 was dissolved in dichloromethane under a nitrogen stream, and then 21.4 ml of triethylamine was added. After cooling to -30°C using an ice bath, it 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. After the organic layer was extracted, washed with distilled water and dried over magnesium sulfate, product 10 was obtained.

After dissolving 10 17.5 (0.047 mol) and 11 9.9 g (0.057 mol) in dimethylformamide under a nitrogen stream, 13 g of potassium carbonate was added. After raising the temperature to 100 °C, it 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 with a solution of n-heptane:ethyl acetate=10:1 on a silica gel column gave product 12 .

^1H 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-( CH3)2 ), 1.32 (t, 3H, CH2- CH3 ).

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

4. Method for preparing a liquid crystal compound of Chemical Formula 1-1d

A liquid crystal compound of 1-((4-(3,4-dimethylphenyl)cyclohexyl)methoxy)-4-ethoxy-2,3-difluorobenzene was prepared as follows.

[Scheme 3]

50.0 g (0.215 mol) of 1 was dissolved in anhydrous tetrahydrofuran under a nitrogen stream. After cooling to -70°C using an ice bath, 104.3 ml of 2.5 M n-butyllithium was added dropwise. After stirring for 1 hour, 40.3 g (0.258 mol) of 13 was dissolved in anhydrous tetrahydrofuran and added dropwise. 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 obtained by eluting with a solution of n-heptane:ethyl acetate=3:1 on a silica gel column.

After dissolving 14 34.2 (0.130 mol) in toluene under a nitrogen stream, 2.4 g of p-toluenesulfonic acid was added. After raising the temperature to 110 °C, it 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 a silica gel column with n-heptane solution gave product 15 .

15 After dissolving 27.1g (0.111mol) in ethanol, 5.4g of 10wt% Pd/C was added. 6 atm of hydrogen gas was applied at room temperature and stirred for 3 hours. After filtering 10wt% Pd/C, the solvent was removed. Recrystallization from ethanol gave product 16 .

After dissolving 16 24.6 (0.100 mol) in toluene under a nitrogen stream, 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. Then, the organic layer was extracted, washed with distilled water, and dried over magnesium sulfate to obtain product 17 .

45.6 g (0.133 mol) of 17 was dissolved in t-butyl methyl under a nitrogen stream. After cooling to -30°C using an ice bath, 14.9 g of potassium thibutoxide 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 l of n-heptane was added to the reaction solution, the resulting solid was separated, and then the organic layer was dried to obtain product 18 .

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

17.1 g (0.079 mol) of 19 was dissolved in anhydrous tetrahydrofuran under a nitrogen stream. After cooling to -30°C using an ice bath, 59.3 ml of 2M boranedimethylsulfide was added dropwise. 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 a silica gel column with n-heptane solution gave product 20 .

After dissolving 15.9 g (0.072 mol) of 20 in dichloromethane under a nitrogen stream, 20.3 ml of triethylamine was added. After cooling to -30°C using an ice bath, it 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. After the organic layer was extracted, washed with distilled water and dried over magnesium sulfate, product 21 was obtained.

After dissolving 21 18.0 (0.048 mol) and 11 10.1 g (0.058 mol) in dimethylformamide under a nitrogen stream, 13 g of potassium carbonate was added. After raising the temperature to 100 °C, it 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 with a solution of n-heptane:ethyl acetate=10:1 on a silica gel column gave the product 22 .

^1H 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-(CH3 )2 ), 1.90 (m, 5H, Cy-H), 1.30 (m, 4H, Cy-H), 1.32 (t, 3H, CH2- CH3 ).

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

5. Method for preparing a liquid crystal compound of Chemical Formula 1-1e

The liquid crystal compound of 4-butoxy-2,3-difluoro-3”,4”-dimethylterphenyl is 4-ethoxy-2,3-difluorophenylboronic acid (4) in the second step Instead, it was prepared according to the manufacturing method mentioned in [Formula 1-1a] using 4-butoxy-2,3-difluorophenylboronic acid.

^1H 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-( CH3)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 ).

6. Method for preparing the liquid crystal compound of Chemical Formula 1-1f

4-butoxy-2,3,3'-trifluoro-3”,4”-dimethylterphenyl instead of 4-ethoxy-2,3-difluorophenylboronic acid (4) of Scheme 1 It was prepared using Scheme 1 using 4-butoxy-2,3-difluorophenylboronic acid.

^1H 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- CH3 ).

7. Method for preparing a liquid crystal compound of Chemical Formula 1-1g

4'-((4-butoxy-2,3-difluorophenoxy)methyl)-3,4-dimethyl-1,1'-biphenyl compound is 4-ethoxy-2,3 of Scheme 2 - It was prepared by the method of Scheme 2 using 4-butoxy-2,3-difluorophenol instead of difluorophenol (13).

^1H 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-( CH3)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 preparing a liquid crystal compound of Chemical Formula 1-1h

1-butoxy-4-((4-(3,4-dimethylphenyl)cyclohexyl)methoxy)-2,3-difluorobenzene is 4-ethoxy-2,3-difluoro It was prepared according to the preparation method mentioned in Scheme 3 using 4-butoxy-2,3-difluorophenol instead of phenol (13).

^1H 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-( CH3)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- CH3 ).

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

9. Method for preparing a liquid crystal compound of Chemical Formula 1-1i

A liquid crystal compound of 2',3'-difluoro-3,4-dimethyl-4”-propylterphenyl was prepared by the following method.

[Scheme 4]

After dissolving 30.0 (0.189 mol) of 22 and 35.9 g (0.158 mol) of 23 in toluene under a nitrogen stream, a 2M aqueous solution of potassium carbonate was added. After raising the temperature to 80°C, 9.1 g (0.008 mol) of Pd(PPh ₃ ) ₄ was added and the mixture was 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 with a n-heptane solution on a silica gel column gave product 24 .

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

After dissolving 1 6.1 (0.026 mol) and 25 9.7 g (0.031 mol) in toluene under a nitrogen stream, a 2M aqueous solution of potassium carbonate was added. After raising the temperature to 80°C, 1.5 g (0.001 mol) of Pd(PPh ₃ ) ₄ was added 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 a silica gel column with n-heptane solution gave product 26 .

^1H 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- CH2 -CH2-CH3), 2.34 (d, 6H, Ar-( CH3)2 , 1.65 (m, 2H, Ar-CH2- CH2 -CH3), 0.90 (t, 3H, Ar-CH2-CH2- CH3 ).

10. Method for preparing the liquid crystal compound of Chemical Formula 1-1j

The liquid crystal compound of 2',3'-difluoro-3,4-dimethyl-4”-pentylterphenyl is 1-pentyl-4 instead of 1-bromo-4-propylbenzene (28) in Scheme 4 -It was prepared according to the manufacturing method mentioned in Scheme 4 using propylbenzene.

^1H 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 H2 -CH2-CH2-CH2-CH3), 2.34 (d, 6H, Ar-( CH3)2 , 1.59 (m, 2H, Ar- 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 property values 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 were defined as extrapolated values obtained by substituting the measured values of a sample prepared by mixing 10% by weight of the liquid crystal compound to be measured and 90% by weight of the mother liquid crystal into Equation 1 below. At this time, as the mother liquid crystal, one having a refractive index anisotropy (n) of 0.11, a dielectric constant anisotropy (ε) of -3.4, and a rotational viscosity (γ ₁ ) of 130 mPa·s was used. The composition of the mother liquid crystal is shown in Table 1 below.

[Equation 1]

Extrapolation = [Measured value of mother liquid crystal] + [{(Measured value of sample) - (Measured value of mother liquid crystal)} / (% by weight of liquid crystal compound) × 100]

(1) Refractive index anisotropy of liquid crystal compounds

The refractive index anisotropy (n) of the liquid crystal compound was measured using an Abbe refractometer equipped with a polarizing plate in 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 polarized light is parallel to the direction of rubbing and the refractive index (n⊥) when the direction of polarized light is perpendicular to the direction of rubbing were measured. Then, the refractive index anisotropy (n) was measured by substituting the refractive index value into Equation 2.

[Equation 2]

n = n - n⊥

(2) Dielectric constant anisotropy of liquid crystal compounds

The dielectric anisotropy (ε) of the liquid crystal compound was calculated by substituting the measured ε and ε⊥ into Equation 3 as follows.

[Equation 3]

ε = ε ∥ - ε⊥

① Measurement of permittivity ε │: A vertical alignment layer was formed by applying a vertical alignment agent to the surface of the two glass substrates on which the ITO patterns were formed. Subsequently, a spacer was applied to either one of the two glass substrates so that the vertical alignment layers faced each other and the distance (cell gap) between the two glass substrates was 4 μm, and then the two glass substrates were bonded together. Then, the sample was injected into the device and sealed with an adhesive cured by ultraviolet rays. After that, using the 4294A equipment manufactured by Agilent, the permittivity ε ∥ of this device was measured at 20 ° C.

② Measurement of dielectric constant ε⊥: A horizontal alignment layer was formed by applying a horizontal alignment agent to the ITO patterned surface of two glass substrates. Subsequently, a spacer was applied to either one of the two glass substrates so that the horizontal alignment films faced each other and the gap (cell gap) between the two glass substrates was 4 μm, and then the two glass substrates were bonded together. Then, the sample was injected into the device and sealed with an adhesive cured by ultraviolet rays. Thereafter, the dielectric constant ε⊥ of the device was measured at 20° C. using a 4294A device manufactured by Agilent.

(3) rotational viscosity of liquid crystal compounds

In order to measure the rotational viscosity (γ ₁ ) of the liquid crystal compound, a device was manufactured in the following manner. A vertical alignment layer was formed by applying a vertical alignment agent to the surfaces of the two glass substrates on which the ITO patterns were formed. Subsequently, a spacer was applied to either one of the two glass substrates so that the vertical alignment layers faced each other and the gap (cell gap) between the two glass substrates was 50 μm, and then the two glass substrates were bonded. Then, the sample was injected into the device and sealed with an adhesive cured by ultraviolet rays. Thereafter, rotational viscosity of the device was measured at 20° C. using a Model 6254 equipment manufactured by Toyo Corp. equipped with a temperature controller manufactured by ESPEC Corp. (Model SU-241).

(4) Tm of liquid crystal compound

The Tm of the liquid crystal compound is the temperature at which a part of the liquid crystal compound changes from a crystal phase to a liquid crystal phase or an isotropic liquid by placing the liquid crystal compound on a hot plate of a melting point measuring device equipped with a polarizing microscope and heating it at a rate of 3°C/min. It was observed and measured.

Evaluation of physical properties of liquid crystal compounds

Table 2 compares physical properties of liquid crystal compounds 1 to 3 of Chemical Formula 1 according to an embodiment of the present invention and conventional liquid crystal compounds 4 and 5. Referring to Table 2, it can be seen that liquid crystal compounds 1 to 3 according to an embodiment of the present invention are superior in rotational viscosity to dielectric anisotropy than liquid crystal compounds 4 and 5 of the related art.

Evaluation of physical properties of liquid crystal composition

Table 3 shows the sign of each functional group for displaying a liquid crystal composition made 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 data below, when comparing the rotational viscosities of Comparative Example and Example 5, the rotational viscosity of the liquid crystal composition of Example 5 was reduced by 35% compared to the rotational viscosity of the liquid crystal composition of Comparative Example. In addition, in the remaining Examples 2 to 4, each liquid crystal composition has a dielectric anisotropy of -2.7 or less and a clearing point of 65 degrees or more, so that it can be applied 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 Clearing point (Tni, ℃) 91.4 Refractive index anisotropy (Δn) 0.1144 Dielectric constant anisotropy (Δε) -4.1 Rotational Viscosity (γ1, 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 ZAYF-1.O2 5.5 ZBYF-1.O2 9.3 ZBYF-1.O4 9.3 Clearing point (Tni, ℃) 69.3 Refractive index anisotropy (Δn) 0.1149 Dielectric constant anisotropy (Δε) -3.4 Rotational Viscosity (γ1, 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 ZAYF-1.O2 6 ZBYF-1.O4 6 ZF-1.O4 6 Clearing point (Tni, ℃) 71.9 Refractive index anisotropy (Δn) 0.1225 Dielectric constant anisotropy (Δε) -3.2 Rotational Viscosity (γ1, 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 ZAYF-1.O2 5.2 ZBYF-1.O2 0 ZBYF-1.O4 5.2 ZFA-1.5 5.2 Clearing point (Tni, ℃) 71.0 Refractive index anisotropy (Δn) 0.1217 Dielectric constant anisotropy (Δε) -2.7 Rotational Viscosity (γ1, 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 Clearing point (Tni, ℃) 72.6 Refractive index anisotropy (Δn) 0.1248 Dielectric constant anisotropy (Δε) -2.9 Rotational Viscosity (γ1, 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 Clearing point (Tni, ℃) 77.3 Refractive index anisotropy (Δn) 0.1472 Dielectric constant anisotropy (Δε) -4.0 Rotational Viscosity (γ1, mPa s) 130

Claims (17)

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 a liquid crystal composition,
wherein the liquid crystal layer includes a liquid crystal compound represented by Chemical Formula 1 below.
[Formula 1]

R ¹ is hydrogen, 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- such that oxygen atoms are not directly connected. , -CF ₂ O-, -O-, -COO-, -OCO- or -OCO-O-, or one or more H may be replaced by halogen,
A ¹ and A ² are each independently cyclohexylene, phenylene, tetrahydropyranylene, dioxanylene, cyclohexenylene, 1,4-bi Among cyclo[2.2.2]octylene (1,4-bicyclo[2.2.2]octylene), pyridinylene, naphthylene, tetrahydronaphthylene or decalinylene As either, one or more H may be replaced with a halogen,
L ¹ and L ² are fluorine, Z ¹ , Z ² and Z ³ are each independently a single bond, -CH ₂ O- or -OCH ₂ -;
n and m are each independently 0, 1 or 2. According to claim 1,
R ¹ is an alkoxy having 1 to 5 carbon atoms. delete A liquid crystal composition comprising a liquid crystal compound represented by Formula 1 below.
[Formula 1]

R ¹ is hydrogen, 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- such that oxygen atoms are not directly connected. , -CF ₂ O-, -O-, -COO-, -OCO- or -OCO-O-, or one or more H may be replaced by halogen,
A ¹ and A ² are each independently cyclohexylene, phenylene, tetrahydropyranylene, dioxanylene, cyclohexenylene, 1,4-bi Among cyclo[2.2.2]octylene (1,4-bicyclo[2.2.2]octylene), pyridinylene, naphthylene, tetrahydronaphthylene or decalinylene As either, one or more H may be replaced with a halogen,
L ¹ and L ² are fluorine, Z ¹ , Z ² and Z ³ are each independently a single bond, -CH ₂ O- or -OCH ₂ -;
n and m are each independently 0, 1 or 2. According to claim 4,
R ¹ is an alkoxy having 1 to 5 carbon atoms. delete According to claim 4,
The liquid crystal compound of Formula 1 is a liquid crystal composition represented by Formula 1-1 below.
[Formula 1-1]

R ¹ , A ¹ , Z ¹ , Z ² , L ¹ , and L ² have the same definitions as in Formula 1. According to claim 7,
The liquid crystal compound represented by Chemical Formula 1-1 is a liquid crystal composition selected from the group consisting of Chemical Formulas 1-1a to 1-1j.
[Formula 1-1a]

[Formula 1-1b]

[Formula 1-1c]

[Formula 1-1d]

[Formula 1-1e]

[Formula 1-1f]

[Formula 1-1g]

[Formula 1-1h]

[Formula 1-1i]

[Formula 1-1j]

According to claim 4,
The liquid crystal compound represented by Formula 1 is contained in 1 to 60% by weight based on the total weight of the liquid crystal composition. The liquid crystal composition according to claim 4, further comprising one or more liquid crystal compounds selected from the group consisting of Formulas 2 to 5:
[Formula 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 one or more of the H may be replaced by halogen;
A ³ and A ⁴ are each independently cyclohexylene or phenylene;
[Formula 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 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 cyclohexylene, phenylene or phenylene substituted with halogen;
p is an integer of 1 or 2;
[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 connected to oxygen atoms. -C≡C-, -CH=CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or one or more of the H may be replaced by halogen;
A ⁸ and A ⁹ are each independently cyclohexylene, tetrahydropyranylene, phenylene or halogen-substituted phenylene;
q is an integer between 0 and 2;
[Formula 5]

In Formula 5, 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 one or more of the H may be replaced by halogen;
A ¹⁰ , A ¹¹ and A ¹² are each independently any one of cyclohexylene, tetrahydropyranylene, phenylene, and halogen-substituted phenylene;
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. According to claim 4,
A liquid crystal composition further comprising an antioxidant selected from the group consisting of compounds represented by Formula 6 and Formula 7:
[Formula 6]

[Formula 7]

In Chemical 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 - of the alkyl or alkoxy group is directly connected to an oxygen atom. -C≡C-, -CH=CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or one or more of the H may be replaced by halogen,
A ¹³ is cyclohexylene, tetrahydropyranylene or dioxanylene. According to claim 4,
A liquid crystal composition further comprising a UV stabilizer selected from the group consisting of compounds represented by Formulas 8 to 10 below.
[Formula 8]

In Formula 8, R ²¹ is hydrogen, oxygen, alkyl having 1 to 15 carbon atoms, or alkoxy having 1 to 15 carbon atoms, and one or more -CH ₂ - of the alkyl or alkoxy group is -C≡C such that oxygen atoms are not directly connected. -, -CH=CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or one or more of the H may be replaced by halogen,
[Formula 9]

In Formula 9, 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 directly connected to the oxygen atom. -C≡C-, -CH=CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or one or more of the H may be replaced by halogen,
f is an integer from 0 to 12;
[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 one or more -CH ₂ - of the alkyl or alkoxy group is -C≡C- so that oxygen atoms are not directly connected. , -CH=CH-, -CF ₂ O-, -O-, -COO- or -OCO-, or one or more of the H may be replaced by halogen,
j is an integer from 0 to 12; A liquid crystal compound represented by Formula 1 below.
[Formula 1]

R ¹ is hydrogen, 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- such that oxygen atoms are not directly connected. , -CF ₂ O-, -O-, -COO-, -OCO- or -OCO-O-, or one or more H may be replaced by halogen,
A ¹ and A ² are each independently cyclohexylene, phenylene, tetrahydropyranylene, dioxanylene, cyclohexenylene, 1,4-bi Among cyclo[2.2.2]octylene (1,4-bicyclo[2.2.2]octylene), pyridinylene, naphthylene, tetrahydronaphthylene or decalinylene As either, one or more H may be replaced with a halogen,
L ¹ and L ² are fluorine, Z ¹ , Z ² and Z ³ are each independently a single bond, -CH ₂ O- or -OCH ₂ -;
n and m are each independently 0, 1 or 2. According to claim 13,
A liquid crystal compound in which R ¹ is an alkoxy having 1 to 5 carbon atoms. delete According to claim 13,
The liquid crystal compound of Formula 1 is a liquid crystal compound represented by Formula 1-1 below.
[Formula 1-1]

R ¹ , A ¹ , Z ¹ , Z ² , L ¹ , and L ² have the same definitions as in Formula 1. According to claim 16,
The liquid crystal compound represented by Chemical Formula 1-1 is a liquid crystal compound selected from the group consisting of Chemical Formulas 1-1a to 1-1j.
[Formula 1-1a]

[Formula 1-1b]

[Formula 1-1c]

[Formula 1-1d]

[Formula 1-1e]

[Formula 1-1f]

[Formula 1-1g]

[Formula 1-1h]

[Formula 1-1i]

[Formula 1-1j]

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