Liquid crystal composition, and optical element and display device comprising same

Abstract

The present invention relates to a liquid crystal composition having excellent optical properties and excellent UV stability, and an optical element and a display device comprising same.

Description

Liquid crystal composition, optical element and display device containing the same

[0001] The present invention relates to a liquid crystal composition, an optical element including the same, and a display device.

[0002]

[0003] Liquid crystal displays (LCDs) are one of the most widely used flat panel displays today. LCDs generate an electric field in a liquid crystal layer by applying voltage to field-generating electrodes, thereby determining the orientation of the liquid crystal molecules in the liquid crystal layer and controlling the transmittance of light passing through the liquid crystal layer, thereby enabling ON / OFF indication. Various modes are being developed, including Twisted Nematic (TN), In-Plane Switching (IPS), Vertically Aligned (VA), Electrically Controlled Birefringence (ECB), Optically Compensatory Bend (OCB), Super Twisted Nematic (STN), Polymer Stabilized Alignment (PSA), and Polymer Stabilized-Vertical Aligned (PS-VA).

[0004] In liquid crystal display devices, liquid crystal compounds are mixed to manufacture a liquid crystal composition in order to meet the product's required characteristics, such as dielectric anisotropy, refractive index anisotropy, clearing point, rotational viscosity, and elastic coefficient.

[0005] At this time, the type and content of the liquid crystal compound used in the production of the liquid crystal composition are adjusted to achieve the required properties. Meanwhile, if a liquid crystal compound with poor UV stability is used in the liquid crystal composition, the liquid crystal composition may become discolored or its reliability may decline due to the UV used to cure the sealant required for bonding the upper and lower substrates in the ODF (One Drop-Filling) process.

[0006] Accordingly, there is a need for technological development for a liquid crystal composition that satisfies the optical properties required by display devices and optical devices and has excellent UV stability.

[0007]

[0008] The present invention provides a liquid crystal composition having excellent optical properties and excellent UV stability, and an optical element and a display device including the same.

[0009] However, the problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned can be clearly understood by those skilled in the art from the description below.

[0010]

[0011] One embodiment of the present invention provides a liquid crystal composition comprising a compound represented by the following chemical formula 1; and a compound represented by the following chemical formula 2; and excluding a compound whose absorbance measured for UV satisfies the following mathematical formula 1, and having a positive dielectric anisotropy:

[0012] [Chemical Formula 1]

[0013]

[0014] [Chemical Formula 2]

[0015]

[0016] [Mathematical Formula 1]

[0017] B / AX 100 ≥ 7.5%

[0018] In the above chemical formula 1, R1 to R5 are each independently hydrogen; a straight-chain or branched-chain alkyl group having 1 to 10 carbon atoms; a straight-chain or branched-chain alkenyl group having 2 to 10 carbon atoms; a straight-chain or branched-chain alkynyl group having 2 to 10 carbon atoms; a straight-chain or branched-chain alkoxy group having 1 to 10 carbon atoms; a halogen group; or a cyano group (-CN); provided that R1 and R2 are not both hydrogen, R3 to R5 are not both hydrogen, R3 to R5 are each independently, and when there are multiple of them, they are the same or different, n, m and p are each independently an integer of 1 to 4,

[0019] In the above chemical formula 2, R 21 Inland R 24 are each independently hydrogen; a straight or branched alkyl group having 1 to 10 carbon atoms; a straight or branched alkenyl group having 2 to 10 carbon atoms; a straight or branched alkynyl group having 2 to 10 carbon atoms; a straight or branched alkoxy group having 1 to 10 carbon atoms; a halogen group; or a cyano group (-CN); and, provided that R 21 and R 22 is not hydrogen at the same time, R 23 Inland R 24 is not hydrogen at the same time, and R 23 Inland R 24 are each independently the same or different when there are multiple of them, and h and i are each independently integers from 1 to 4,

[0020] In the above mathematical expression 1, A is the total area of ​​the absorbance curve from the first inflection point to the final inflection point in the absorbance measurement wavelength range, and B is the area of ​​the absorbance curve from the 330 nm point to the final inflection point in the absorbance measurement wavelength range.

[0021] According to one embodiment of the present invention, the compound represented by the chemical formula 1 may include a compound represented by the following chemical formula 1-1, and the compound represented by the chemical formula 2 may include a compound represented by the following chemical formula 2-1:

[0022] [Chemical Formula 1-1]

[0023]

[0024] [Chemical Formula 2-1]

[0025]

[0026] In the above chemical formula 1-1, R1 and R2 are each independently a straight or branched alkyl group having 1 to 5 carbon atoms; a halogen group; or a cyano group (-CN), and R3 to R5 are each independently hydrogen; a straight or branched alkyl group having 1 to 5 carbon atoms; a straight or branched alkenyl group having 2 to 5 carbon atoms; a straight or branched alkynyl group having 2 to 5 carbon atoms; a straight or branched alkoxy group having 1 to 5 carbon atoms; or a halogen group; and when there are multiple of them, they are the same or different, and at least one of R3 to R5 is a halogen group, and n, m and p are each independently an integer of 1 to 4,

[0027] In the above chemical formula 2-1, R 21 and R 22 are each independently a straight or branched alkyl group having 1 to 5 carbon atoms; a straight or branched alkenyl group having 2 to 5 carbon atoms; a straight or branched alkoxy group having 1 to 5 carbon atoms; a halogen group; or a cyano group (-CN); and R 23 and R 24 are each independently hydrogen; a straight-chain or branched alkyl group having 1 to 5 carbon atoms; a straight-chain or branched alkenyl group having 2 to 5 carbon atoms; a straight-chain or branched alkynyl group having 2 to 5 carbon atoms; a straight-chain or branched alkoxy group having 1 to 5 carbon atoms; or a halogen group; and when there are multiple of them, they are the same or different, and h and i are each independently an integer of 1 to 4.

[0028] According to one embodiment of the present invention, the compound represented by the chemical formula 1 may include a compound represented by the following chemical formula 1-2, and the compound represented by the chemical formula 2 may include a compound represented by the following chemical formula 2-2:

[0029] [Chemical Formula 1-2]

[0030]

[0031] [Chemical Formula 2-2]

[0032]

[0033] In the above chemical formula 1-2, R1 and R2 are each independently a straight or branched alkyl group having 1 to 5 carbon atoms; a halogen group; or a cyano group (-CN), R3 and R5 are each independently hydrogen; a straight or branched alkyl group having 1 to 5 carbon atoms; or a halogen group; and when there are multiple of them, they are the same or different, R4 is a halogen group, n and p are each independently an integer of 1 to 4,

[0034] In the above chemical formula 2-2, R 21 and R 22 are each independently a straight or branched alkyl group having 1 to 5 carbon atoms; a straight or branched alkenyl group having 2 to 5 carbon atoms; a straight or branched alkoxy group having 1 to 5 carbon atoms; a halogen group; or a cyano group (-CN); and R 23 is hydrogen; a straight or branched alkyl group having 1 to 5 carbon atoms; or a halogen group; and when there are multiple of them, they are the same or different, and R 24 is hydrogen; or a halogen group; and h is an integer from 1 to 4.

[0035] According to one embodiment of the present invention, in the chemical formula 1, at least one of R1 and R2 may be a straight or branched alkyl group having 1 to 10 carbon atoms; or a cyano group.

[0036] According to one embodiment of the present invention, in the chemical formula 1, at least one of R3 to R5 may be a fluoro group (-F).

[0037] According to one embodiment of the present invention, in the chemical formula 2, R 21 and R 22 At least one of them may be a straight or branched chain alkoxy group having 1 to 5 carbon atoms.

[0038] According to one embodiment of the present invention, the compound represented by the chemical formula 1 may include at least one of the following compounds:

[0039] Compound 1-1 Compound 1-2

[0040]

[0041] Compound 1-3 <Compound 1-4>

[0042]

[0043] Compound 1-5 <Compound 1-6>

[0044]

[0045] Compound 1-7 Compound 1-8

[0046]

[0047] Compound 1-9

[0048] .

[0049] According to one embodiment of the present invention, the compound represented by the chemical formula 2 may include at least one of the following compounds:

[0050] Compound 2-1 <Compound 2-2>

[0051]

[0052] Compound 2-3 <Compound 2-4>

[0053]

[0054] Compound 2-5 <Compound 2-6>

[0055] .

[0056] According to one embodiment of the present invention, based on 100 parts by weight of the liquid crystal composition, the sum of the content of the compound represented by the chemical formula 1 and the content of the compound represented by the chemical formula 2 may be 16 parts by weight or more.

[0057] According to one embodiment of the present invention, the weight ratio of the compound represented by the chemical formula 1 and the compound represented by the chemical formula 2 may be 1:0.2 to 1:10.

[0058] According to one embodiment of the present invention, a compound satisfying the above mathematical formula 1 may include three or more aromatic rings having 6 to 30 carbon atoms and may include at least one alkynylene bond connecting adjacent aromatic rings.

[0059] According to one embodiment of the present invention, the refractive index anisotropy of the liquid crystal composition may be 0.15 or more and 0.25 or less.

[0060] According to one embodiment of the present invention, the dielectric anisotropy of the liquid crystal composition may be 3 or more and 15 or less.

[0061] According to one embodiment of the present invention, the liquid crystal composition can satisfy the following mathematical formula 2:

[0062] [Equation 2]

[0063] (DC) / CX 100 < 100 %

[0064] In the above mathematical expression 2, C is the yellow index value of the liquid crystal composition before UV irradiation, and D is the yellow index value of the liquid crystal composition after irradiation with UV having a wavelength of 365 nm and an energy of 3 J.

[0065] One embodiment of the present invention provides an optical element including the liquid crystal composition.

[0066] One embodiment of the present invention provides a display device including the liquid crystal composition.

[0067]

[0068] A liquid crystal composition according to one embodiment of the present invention can have excellent UV stability while implementing excellent optical properties.

[0069] In addition, a display device according to one embodiment of the present invention may have excellent quality and reliability by including the liquid crystal composition.

[0070] In addition, an optical element according to one embodiment of the present invention may have excellent optical properties by including the liquid crystal composition.

[0071] The effects of the present invention are not limited to the effects described above, and effects not mentioned will be clearly understood by those skilled in the art from the present specification and the attached drawings.

[0072]

[0073] Figure 1 shows the results of UV absorbance measurement of a compound represented by Chemical Formula 1, a compound represented by Chemical Formula 2, and a compound represented by Chemical Formula 3 according to one embodiment of the present invention.

[0074] Figures 2a and 2b show the results of UV absorbance measurements for a compound with the code EMAA-2.3.

[0075]

[0076] Throughout this specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0077] Throughout this specification, when it is said that an element is "on" another element, this includes not only cases where the element is in contact with the other element, but also cases where another element exists between the two elements.

[0078] Throughout this specification, the unit “parts by weight” may mean the weight ratio between each component.

[0079] Throughout this specification, terms containing ordinal numbers, such as "first" and "second," are used to distinguish one component from another and are not limited by the ordinal numbers. For example, within the scope of the invention, the first component may also be referred to as the second component, and similarly, the second component may be referred to as the first component.

[0080]

[0081] Hereinafter, the present specification will be described in more detail.

[0082] One embodiment of the present invention provides a liquid crystal composition comprising a compound represented by the following chemical formula 1; and a compound represented by the following chemical formula 2; and excluding a compound whose absorbance measured for UV satisfies the following mathematical formula 1, and having a positive dielectric anisotropy:

[0083] [Chemical Formula 1]

[0084]

[0085] [Chemical Formula 2]

[0086]

[0087] [Mathematical Formula 1]

[0088] B / AX 100 ≥ 7.5%

[0089] In the above chemical formula 1, R1 to R5 are each independently hydrogen; a straight chain or branched chain alkyl group having 1 to 10 carbon atoms; a straight chain or branched chain alkenyl group having 2 to 10 carbon atoms; a straight chain or branched chain alkynyl group having 2 to 10 carbon atoms; a straight chain or branched chain alkoxy group having 1 to 10 carbon atoms; a halogen group; or a cyano group (-CN); provided that R1 and R2 are not hydrogen at the same time, R3 to R5 are not hydrogen at the same time, R3 to R5 are each independently, and when there are multiple of them, they are the same or different, n, m and p are each independently an integer of 1 to 4, and in the above chemical formula 2, R 21 Inland R 24 are each independently hydrogen; a straight or branched alkyl group having 1 to 10 carbon atoms; a straight or branched alkenyl group having 2 to 10 carbon atoms; a straight or branched alkynyl group having 2 to 10 carbon atoms; a straight or branched alkoxy group having 1 to 10 carbon atoms; a halogen group; or a cyano group (-CN); and, provided that R 21 and R 22 is not hydrogen at the same time, R 23 Inland R 24 is not hydrogen at the same time, and R 23 Inland R 24 are each independently the same or different when there are multiple of them, h and i are each independently integers from 1 to 4, and in the above mathematical expression 1, A is the total area for the absorbance curve from the first inflection point to the final inflection point in the absorbance measurement wavelength range, and B is the area for the absorbance curve from the 330 nm point to the final inflection point in the absorbance measurement wavelength range.

[0090] A liquid crystal composition according to one embodiment of the present invention can exhibit excellent optical properties while also exhibiting excellent UV stability. Specifically, the liquid crystal composition comprises a compound represented by the above chemical formula 1 and a compound represented by the above chemical formula 2, but does not include a compound satisfying the above mathematical formula 1, thereby exhibiting excellent optical properties such as refractive index anisotropy and dielectric anisotropy, while at the same time very effectively improving stability against UV.

[0091] According to one embodiment of the present invention, the compound represented by the chemical formula 1 corresponds to a compound having sufficient refractive index anisotropy and a high phase transition temperature, so that the liquid crystal composition including the compound represented by the chemical formula 1 can have excellent optical properties such as refractive index anisotropy and dielectric anisotropy. In addition, the compound represented by the chemical formula 2 corresponds to a compound having sufficient refractive index anisotropy and a low rotational viscosity, so that the liquid crystal composition including the compound represented by the chemical formula 2 can have excellent optical properties such as refractive index anisotropy and dielectric anisotropy. Accordingly, the response time required for driving a display device and an optical device including the liquid crystal composition can be improved.

[0092] According to one embodiment of the present invention, R1 to R5 of the chemical formula 1 and R of the chemical formula 2 21 Inland R 24In , the number of carbon atoms contained in the alkyl group may be 1 to 10, 1 to 8, 1 to 6, 1 to 4, or 1 to 2. In addition, the number of carbon atoms contained in the alkenyl group (including a double bond between carbon atoms) may be 2 to 10, 2 to 8, 2 to 6, or 2 to 4. In addition, the number of carbon atoms contained in the alkynyl group (including a triple bond between carbon atoms) may be 2 to 10, 2 to 8, 2 to 6, or 2 to 4. In addition, the number of carbon atoms contained in the alkoxy group may be 1 to 10, 1 to 8, 1 to 6, 1 to 4, or 1 to 2. In addition, the halogen group may be a fluoro group (-F), a chloro group (-Cl), a bromo group (-Br), or an iodine group (-I). Specifically, the halogen group may be a fluoro group (-F). In addition, in the above chemical formula 1, n, m, and p may each independently be an integer of 1 to 4, an integer of 1 to 2, or 1. In addition, in the above chemical formula 2, h and i may each independently be an integer of 1 to 4, an integer of 1 to 2, or 1. At this time, the double bond present in the alkenyl group of the chemical formula 2 may be located at the terminal. The liquid crystal composition including the compound represented by the above chemical formula 1 and the compound represented by the above chemical formula 2, wherein the types of substituents satisfy the above-described ones, may have excellent optical properties.

[0093] According to one embodiment of the present invention, in the chemical formula 1, at least one of R1 and R2 may be a straight or branched alkyl group having 1 to 10 carbon atoms; a cyano group; or a halogen group. In addition, in the chemical formula 2, R 21 and R 22 At least one of them may be a straight or branched chain alkyl group having 1 to 10 carbon atoms; a cyano group; or a halogen group.

[0094] In the above chemical formula 1, when at least one of R1 and R2 is a cyano group, the refractive index anisotropy and dielectric anisotropy of the liquid crystal composition can be effectively improved. In addition, in the above chemical formula 2, R 21 and R 22 When at least one of them is a cyano group, the refractive index anisotropy and dielectric anisotropy of the liquid crystal composition can be effectively improved.

[0095] In the above chemical formula 1, when at least one of R1 and R2 is a halogen group, the refractive index anisotropy of the liquid crystal composition can be reduced and the dielectric anisotropy can be improved. At this time, the halogen group can be a fluoro group (-F). In addition, in the above chemical formula 2, R 21 and R 22 When at least one of the groups is a halogen group, the refractive index anisotropy of the liquid crystal composition can be reduced and the dielectric anisotropy can be improved. At this time, the halogen group can be a fluoro group (-F).

[0096] That is, the liquid crystal composition according to one embodiment of the present invention can easily control the optical properties of the desired liquid crystal composition by controlling the types of the substituents of the chemical formula 1 and the substituents of the chemical formula 2.

[0097] According to one embodiment of the present invention, the compound represented by the chemical formula 1 may include a compound represented by the following chemical formula 1-1, and the compound represented by the chemical formula 2 may include a compound represented by the following chemical formula 2-1:

[0098] [Chemical Formula 1-1]

[0099]

[0100] [Chemical Formula 2-1]

[0101]

[0102] In the above chemical formula 1-1, R1 and R2 are each independently a straight or branched alkyl group having 1 to 5 carbon atoms; a halogen group; or a cyano group (-CN), and R3 to R5 are each independently hydrogen; a straight or branched alkyl group having 1 to 5 carbon atoms; a straight or branched alkenyl group having 2 to 5 carbon atoms; a straight or branched alkynyl group having 2 to 5 carbon atoms; a straight or branched alkoxy group having 1 to 5 carbon atoms; or a halogen group; and when there are multiple of them, they are the same or different, and at least one of R3 to R5 is a halogen group, and n, m and p are each independently an integer of 1 to 4,

[0103] In the above chemical formula 2-1, R 21 and R 22 are each independently a straight or branched alkyl group having 1 to 5 carbon atoms; a straight or branched alkenyl group having 2 to 5 carbon atoms; a straight or branched alkoxy group having 1 to 5 carbon atoms; a halogen group; or a cyano group (-CN); and R 23 and R 24 are each independently hydrogen; a straight-chain or branched alkyl group having 1 to 5 carbon atoms; a straight-chain or branched alkenyl group having 2 to 5 carbon atoms; a straight-chain or branched alkynyl group having 2 to 5 carbon atoms; a straight-chain or branched alkoxy group having 1 to 5 carbon atoms; or a halogen group; and when there are multiple of them, they are the same or different, and h and i are each independently an integer of 1 to 4.

[0104] In the compound represented by the above chemical formula 1-1, the positions of R1 and R2 are fixed and the types of R1 to R5 are specified compared to the compound represented by the above chemical formula 1, so that the liquid crystal composition including the compound represented by the above chemical formula 1-1 can have improved optical properties such as refractive index anisotropy and dielectric anisotropy.

[0105] In addition, the compound represented by the above chemical formula 2-1 has R compared to the compound represented by the above chemical formula 2. 21 and R22 The position of R is fixed, 21 Inland R 24 As the type is specified, the liquid crystal composition including the compound represented by the chemical formula 2-1 can have improved optical properties such as refractive index anisotropy and dielectric anisotropy.

[0106] According to one embodiment of the present invention, the compound represented by the chemical formula 1 may include a compound represented by the following chemical formula 1-2, and the compound represented by the chemical formula 2 may include a compound represented by the following chemical formula 2-2:

[0107] [Chemical Formula 1-2]

[0108]

[0109] [Chemical Formula 2-2]

[0110]

[0111] In the above chemical formula 1-1, R1 and R2 are each independently a straight or branched alkyl group having 1 to 5 carbon atoms; a halogen group; or a cyano group (-CN), R3 and R5 are each independently hydrogen; a straight or branched alkyl group having 1 to 5 carbon atoms; or a halogen group; and when there are multiple of them, they are the same or different, R4 is a halogen group, n and p are each independently an integer of 1 to 4, and in the above chemical formula 2-1, R 21 and R 22 are each independently a straight or branched alkyl group having 1 to 5 carbon atoms; a straight or branched alkenyl group having 2 to 5 carbon atoms; a straight or branched alkoxy group having 1 to 5 carbon atoms; a halogen group; or a cyano group (-CN); and R 23 is hydrogen; a straight or branched alkyl group having 1 to 5 carbon atoms; or a halogen group; and when there are multiple of them, they are the same or different, and R 24 is hydrogen; or a halogen group; and h is an integer from 1 to 4.

[0112] In the compound represented by the above chemical formula 1-2, the position of R4 is fixed and the types of R1 to R5 are specified compared to the compound represented by the above chemical formula 1-1, so that the liquid crystal composition including the compound represented by the above chemical formula 1-2 can have improved optical properties such as refractive index anisotropy and dielectric anisotropy.

[0113] In addition, the compound represented by the above chemical formula 2-2 has R compared to the compound represented by the above chemical formula 2-1. 24 The position of R is fixed, 21 Inland R 24 As the type is specified, the liquid crystal composition including the compound represented by the chemical formula 2-2 can have improved optical properties such as refractive index anisotropy and dielectric anisotropy.

[0114] According to one embodiment of the present invention, the compound represented by the above chemical formula 1 may contain at least one halogen group. Specifically, the halogen group may be a fluoro group (-F). When the compound represented by the above chemical formula 1 containing a halogen group is used, the refractive index anisotropy of the liquid crystal composition can be lowered and the dielectric anisotropy can be improved. In addition, the compound represented by the above chemical formula 2 may also contain at least one halogen group. Specifically, the halogen group may be a fluoro group (-F). When the compound represented by the above chemical formula 2 containing a halogen group is used, the refractive index anisotropy of the liquid crystal composition can be lowered and the dielectric anisotropy can be improved.

[0115] According to one embodiment of the present invention, when R2 in the chemical formula 1-2 is a halogen group, the refractive index anisotropy of the liquid crystal composition can be reduced compared to when R2 is a cyano group.

[0116] According to one embodiment of the present invention, in the chemical formula 1, at least one of R1 and R2 may be a straight-chain or branched-chain alkyl group having 1 to 10 carbon atoms; or a cyano group. In this case, when a compound represented by the chemical formula 1, in which at least one of R1 and R2 is a cyano group instead of a straight-chain or branched-chain alkyl group having 1 to 10 carbon atoms, is used, the optical properties of the liquid crystal composition can be further improved. Specifically, the refractive index anisotropy of the liquid crystal composition can be increased and the dielectric anisotropy can be improved.

[0117] Meanwhile, when R1 and R2 in the above chemical formula 1 are the same, specifically, when they are a halogen group, a cyano group, or an alkoxy group, the polarities of both ends of the chemical formula 1 become equal, so that electron mobility is low, which may cause a problem of lowering the dielectric anisotropy of the liquid crystal composition. On the other hand, when one of R1 and R2 in the above chemical formula 1 is a straight or branched alkyl group having 1 to 10 carbon atoms and the other is a halogen group, a cyano group, or an alkoxy group, the polarities of both ends of the chemical formula 1 become different, so that electron mobility is high, which can effectively improve the refractive index anisotropy and the dielectric anisotropy of the liquid crystal composition.

[0118] In addition, in the above chemical formula 2, R 21 and R 22 In the case where R is the same, specifically a halogen group, a cyano group or an alkoxy group, the polarity of both ends of the chemical formula 2 becomes equal, so that the electron mobility is low, and the problem of the dielectric anisotropy of the liquid crystal composition being lowered may occur. On the other hand, in the chemical formula 2, R 21 and R 22 When one of them is a straight or branched alkyl group having 1 to 10 carbon atoms and the other is a halogen group, cyano group or alkoxy group, the polarities of the two terminals of chemical formula 2 become different, so that electron mobility is high, and thus the refractive index anisotropy and dielectric anisotropy of the liquid crystal composition can be effectively improved.

[0119] According to one embodiment of the present invention, in the chemical formula 1, R1 and R2 may each independently be a straight-chain or branched-chain alkyl group having 1 to 10 carbon atoms. At this time, R1 and R2 may be the same as or different from each other. Specifically, R1 and R2 may be a straight-chain alkyl group having 1 to 8 carbon atoms, 1 to 6 carbon atoms, or 1 to 4 carbon atoms. When R1 and R2 are of the above-mentioned types, the optical properties of the liquid crystal composition may be further improved.

[0120] According to one embodiment of the present invention, in the chemical formula 2, R 21 and R 22 At least one of the groups may be a straight or branched chain alkyl group having 1 to 10 carbon atoms; a straight or branched chain alkenyl group having 2 to 10 carbon atoms; a straight or branched chain alkoxy group having 1 to 10 carbon atoms; or a halogen group.

[0121] In the above chemical formula 2, R 21 and R 22 When the liquid crystal composition including the compound represented by the above chemical formula 2 is of the above-mentioned type, it is possible to easily realize improved optical properties.

[0122] According to one embodiment of the present invention, in the chemical formula 1, at least one of R3 and R5 is hydrogen; or a halogen group; and in the chemical formula 2, R 23 and R 24 At least one of them may be hydrogen; or a halogen group; In the above chemical formula 1, R3 and R5 are of the above-mentioned types, and in the above chemical formula 2, R 23 and R 24 When the liquid crystal composition is of the above-mentioned type, the liquid crystal composition including the compound represented by the chemical formula 1 and the compound represented by the chemical formula 2 can easily realize more improved optical properties.

[0123] According to one embodiment of the present invention, in the chemical formula 1, at least one of R3 to R5 may be a fluoro group (-F). The liquid crystal composition including the compound represented by the chemical formula 1 satisfying this may have improved optical properties such as refractive index anisotropy.

[0124] According to one embodiment of the present invention, in the chemical formula 2, R 21 and R 22 At least one of R may be a straight or branched chain alkoxy group having 1 to 5 carbon atoms. 21 and R 22 The liquid crystal composition including the compound represented by the chemical formula 2, which is the type described above, can have improved optical properties such as refractive index anisotropy.

[0125] According to one embodiment of the present invention, the compound represented by the chemical formula 1 may include at least one of the following compounds:

[0126] Compound 1-1 Compound 1-2

[0127]

[0128] Compound 1-3 <Compound 1-4>

[0129]

[0130] Compound 1-5 <Compound 1-6>

[0131]

[0132] Compound 1-7 Compound 1-8

[0133]

[0134] Compound 1-9

[0135] .

[0136] When the compound represented by the above chemical formula 1 includes at least one of the compounds described above, a liquid crystal composition having excellent optical properties such as refractive index anisotropy and dielectric anisotropy can be more easily provided.

[0137] According to one embodiment of the present invention, the compound represented by the chemical formula 2 may include at least one of the following compounds:

[0138] Compound 2-1 <Compound 2-2>

[0139]

[0140] Compound 2-3 <Compound 2-4>

[0141]

[0142] Compound 2-5 <Compound 2-6>

[0143] .

[0144] When the compound represented by the above chemical formula 2 includes at least one of the compounds described above, a liquid crystal composition having excellent optical properties such as refractive index anisotropy and dielectric anisotropy can be more easily provided.

[0145] According to one embodiment of the present invention, based on 100 parts by weight of the liquid crystal composition, the sum of the content of the compound represented by the chemical formula 1 and the content of the compound represented by the chemical formula 2 may be 15 parts by weight or more, 16 parts by weight or more, 20 parts by weight or more, 25 parts by weight or more, 30 parts by weight or more, 35 parts by weight or more, 37.5 parts by weight or more, 40 parts by weight or more, 42 parts by weight or more, 45 parts by weight or more, 47 parts by weight or more, 50 parts by weight or more, 55 parts by weight or more, or 60 parts by weight or more. In addition, based on 100 parts by weight of the liquid crystal composition, the sum of the content of the compound represented by the chemical formula 1 and the content of the compound represented by the chemical formula 2 may be 75 parts by weight or less, 70 parts by weight or less, 67.5 parts by weight or less, 65 parts by weight or less, 60 parts by weight or less, or 55 parts by weight or less. When the total content of the compound represented by the chemical formula 1 and the compound represented by the chemical formula 2 contained in the liquid crystal composition satisfies the above-described range, the optical properties of the liquid crystal composition can be improved. Specifically, the refractive index anisotropy of the liquid crystal composition can be effectively improved. In particular, when the total content of the compound represented by the chemical formula 1 and the compound represented by the chemical formula 2 is 16 parts by weight or more, specifically 35 parts by weight or more, based on 100 parts by weight of the liquid crystal composition, the optical properties of the liquid crystal composition can be further improved.

[0146] According to one embodiment of the present invention, based on 100 parts by weight of the liquid crystal composition, the content of the compound represented by the chemical formula 1 may be 3 parts by weight or more and 45 parts by weight or less. Specifically, the content of the compound represented by the chemical formula 1 may be 5 parts by weight or more and 40 parts by weight or less, 10 parts by weight or more and 37.5 parts by weight or less, 15 parts by weight or more and 30 parts by weight or less, 5 parts by weight or more and 25 parts by weight or less, 5 parts by weight or more and 20 parts by weight or less, 5 parts by weight or more and 15 parts by weight or less, 5 parts by weight or more and 10 parts by weight or less, 15 parts by weight or more and 45 parts by weight or less, 20 parts by weight or more and 37.5 parts by weight or less, or 25 parts by weight or more and 35 parts by weight or less, based on 100 parts by weight of the liquid crystal composition. When the content of the compound represented by the chemical formula 1 is within the above-mentioned range, the optical properties of the liquid crystal composition may be improved. Specifically, the dielectric anisotropy of the liquid crystal composition can be effectively improved.

[0147] According to one embodiment of the present invention, based on 100 parts by weight of the liquid crystal composition, the content of the compound represented by the chemical formula 2 may be 5 parts by weight or more and 65 parts by weight or less. Specifically, the content of the compound represented by the chemical formula 2 may be 7 parts by weight or more and 60 parts by weight or less, 10 parts by weight or more and 60 parts by weight or less, 15 parts by weight or more and 55 parts by weight or less, 20 parts by weight or more and 50 parts by weight or less, 25 parts by weight or more and 45 parts by weight or less, 5 parts by weight or more and 45 parts by weight or less, 10 parts by weight or more and 40 parts by weight or less, 15 parts by weight or more and 35 parts by weight or less, 25 parts by weight or more and 65 parts by weight or less, or 30 parts by weight or more and 60 parts by weight or less, based on 100 parts by weight of the liquid crystal composition. When the content of the compound represented by the chemical formula 2 is within the above-mentioned range, the optical properties of the liquid crystal composition may be improved. Specifically, the dielectric anisotropy of the liquid crystal composition can be effectively improved.

[0148] According to one embodiment of the present invention, the weight ratio of the compound represented by the chemical formula 1 to the compound represented by the chemical formula 2 may be 1:0.2 to 1:11. Specifically, the weight ratio of the compound represented by the chemical formula 1 to the compound represented by the chemical formula 2 may be 1:0.2 to 1:10, 1:0.4 to 1:10, 1:0.6 to 1:10, 1:0.8 to 1:8, 1:1 to 1:6, 1:0.2 to 1:5, 1:0.5 to 1:4, 1:0.5 to 1:2.5, 1:0.5 to 1:1.5, 1:4 to 1:10, 1:6 to 1:10, or 1:8 to 1:10. By adjusting the weight ratio of the compound represented by the above chemical formula 1 and the compound represented by the above chemical formula 2 within the above-mentioned range, a liquid crystal composition having excellent optical properties such as refractive index anisotropy and dielectric anisotropy can be easily implemented.

[0149] According to one embodiment of the present invention, the liquid crystal composition may not include a compound whose absorbance measured for UV satisfies the above mathematical formula 1. That is, the non-included compound may have a value calculated by the following mathematical formula 1-1 of 7.5% or more.

[0150] [Mathematical Formula 1-1]

[0151] B / AX 100 (%)

[0152] In the above mathematical expression 1-1, A is the total area of ​​the absorbance curve from the first inflection point to the final inflection point in the absorbance measurement wavelength range, and B is the area of ​​the absorbance curve from the 330 nm point to the final inflection point in the absorbance measurement wavelength range.

[0153] At this time, in the above mathematical expressions 1 and 1-1, the wavelength range for measuring absorbance may be 200 nm or more and 800 nm or less, or 200 nm or more and 400 nm or less.

[0154] Figure 1 shows the results of UV absorbance measurement of a compound represented by Chemical Formula 1, a compound represented by Chemical Formula 2, and a compound represented by Chemical Formula 3 according to one embodiment of the present invention.

[0155] Referring to FIG. 1, in the case of the compound represented by Chemical Formula 3 (a compound satisfying Chemical Formula 1), there is a region where the absorbance exceeds 0 in the wavelength range of 330 nm to 380 nm in which the ODF (One Drop-Filling) process is performed. Accordingly, in the case of the liquid crystal composition including the compound represented by Chemical Formula 3 (a compound satisfying Chemical Formula 1), there occurs a problem that the liquid crystal composition is discolored or its reliability is reduced due to UV during the ODF process. On the other hand, as described above, the liquid crystal composition according to one embodiment of the present invention can effectively solve the problem that the liquid crystal composition is discolored or its reliability is reduced due to UV during the ODF process by excluding the compound satisfying Chemical Formula 1 in relation to the wavelength range of 330 nm to 380 nm in which the ODF process is performed.

[0156] Figures 2a and 2b show the results of UV absorbance measurements for a compound with the code EMAA-2.3.

[0157] Referring to Fig. 2a, it can be seen that the compound EMAA-2.3 exhibits a first inflection point (first inflection point; IP1), a second inflection point (IP2), and a final inflection point (third inflection point; IP3) in the absorbance measurement wavelength range of 200 nm to 400 nm. In this case, A in the above mathematical expression 1-1 corresponds to the total area of ​​the absorbance measurement curve from the first inflection point (first inflection point; IP1) to the final inflection point (third inflection point; IP3).

[0158] Referring to Fig. 2b, B in the above mathematical expression 1-1 corresponds to the area of ​​the absorbance curve from the 330 nm point to the final inflection point (the third inflection point; IP3).

[0159] According to one embodiment of the present invention, the compound represented by the chemical formula 1 may have a value calculated by the mathematical formula 1-1 of 0% or more and 5% or less, 0% or more and 3% or less, or 0% or more and 1% or less. Specifically, the compound represented by the chemical formula 1 may have a value calculated by the mathematical formula 1-1 of 0%. In addition, the compound represented by the chemical formula 2 may have a value calculated by the mathematical formula 1-1 of 0% or more and 5% or less, 0% or more and 3% or less, or 0% or more and 1% or less. Specifically, the compound represented by the chemical formula 2 may have a value calculated by the mathematical formula 1-1 of 0%.

[0160] In addition, the nonpolar compound described below may have a value calculated by the above mathematical formula 1-1 of 0% or more and 5% or less, 0% or more and 3% or less, or 0% or more and 1% or less. Specifically, the nonpolar compound may have a value calculated by the above mathematical formula 1-1 of 0%. In addition, the polar compound described below may have a value calculated by the above mathematical formula 1-1 of 0% or more and 5% or less, 0% or more and 3% or less, or 0% or more and 1% or less. Specifically, the polar compound may have a value calculated by the above mathematical formula 1-1 of 0%.

[0161] According to one embodiment of the present invention, the compound satisfying the mathematical formula 1 may include three or more aromatic rings having 6 to 30 carbon atoms, and may include at least one alkynylene bond connecting adjacent aromatic rings. Specifically, the compound satisfying the mathematical formula 1 may include three to six, three to five, three to four, or three aromatic rings having 6 to 30 carbon atoms. In addition, the compound satisfying the mathematical formula 1 may include one alkynylene bond connecting adjacent aromatic rings.

[0162] According to one embodiment of the present invention, the compound satisfying the above mathematical formula 1 may include a compound represented by the following chemical formula 3:

[0163] [Chemical Formula 3]

[0164]

[0165] In the above chemical formula 3, the R 31 and R 32 are each independently a straight or branched alkyl group having 1 to 10 carbon atoms; a straight or branched alkenyl group having 2 to 10 carbon atoms; or a straight or branched alkynyl group having 2 to 10 carbon atoms; a straight or branched alkoxy group having 1 to 10 carbon atoms; a halogen group; or a cyano group (-CN); and the R 33 Inland R 35 are each independently hydrogen; a straight or branched alkyl group having 1 to 10 carbon atoms; a straight or branched alkenyl group having 2 to 10 carbon atoms; a straight or branched alkynyl group having 2 to 10 carbon atoms; a straight or branched alkoxy group having 1 to 10 carbon atoms; or a halogen group; and R 33 Inland R 35 are each independently the same or different when there are multiple of them, and a, b and c are each independently integers from 1 to 4.

[0166] According to one embodiment of the present invention, the compound satisfying the above mathematical formula 1 may include a compound represented by the following chemical formula 3-1:

[0167] [Chemical Formula 3-1]

[0168]

[0169] In the above chemical formula 3-1, the R 31 and R 32 are each independently a straight or branched alkyl group having 1 to 10 carbon atoms; a straight or branched alkoxy group having 1 to 10 carbon atoms; a halogen group; or a cyano group (-CN); and R 33 Inland R35 are each independently hydrogen; or a halogen group; and when there are multiple of them, they are the same or different, and a, b, and c are each independently an integer from 1 to 4.

[0170] According to one embodiment of the present invention, the compound represented by the chemical formula 3 may include at least one of the following compounds:

[0171] Compound 3-1 Compound 3-2

[0172]

[0173] Compound 3-3

[0174] .

[0175] The above liquid crystal composition that does not contain the above-mentioned type of compound can exhibit very excellent stability against UV.

[0176] According to one embodiment of the present invention, the liquid crystal composition may further include a nonpolar compound including at least one of an alicyclic ring having 5 to 10 carbon atoms and an aromatic ring having 6 to 30 carbon atoms; and a polar compound including at least one of an alicyclic ring having 5 to 10 carbon atoms and an aromatic ring having 6 to 30 carbon atoms.

[0177] According to one embodiment of the present invention, the nonpolar compound may include a compound represented by the following chemical formula 4:

[0178] [Chemical Formula 4]

[0179]

[0180] In the above chemical formula 4, A1 to A3 are each independently an alicyclic ring having 5 to 10 carbon atoms; or an aromatic ring having 6 to 30 carbon atoms; and at least one of A1 to A3 is an alicyclic ring having 5 to 10 carbon atoms, and R 41 and R 42are each independently a straight or branched chain alkyl group having 1 to 10 carbon atoms; a straight or branched chain alkenyl group having 2 to 10 carbon atoms; a straight or branched chain alkynyl group having 2 to 10 carbon atoms; or a straight or branched chain alkoxy group having 1 to 10 carbon atoms; and R 43 Inland R 45 are each independently hydrogen; a straight or branched alkyl group having 1 to 10 carbon atoms; a straight or branched alkenyl group having 2 to 10 carbon atoms; a straight or branched alkynyl group having 2 to 10 carbon atoms; a straight or branched alkoxy group having 1 to 10 carbon atoms; or a halogen group; and R 43 Inland R 45 are each independently the same or different when there are multiple of them, n1 is 0 or 1, and d, e and f are each independently integers from 1 to 4.

[0181] According to one embodiment of the present invention, A1 to A3 may each independently be cyclohexane or benzene. At this time, at least one of A1 to A3 may be cyclohexane. R of the chemical formula 4 41 Inland R 45 In , the number of carbon atoms contained in the alkyl group may be 1 to 10, 1 to 8, 1 to 6, 1 to 4, or 1 to 2. In addition, the number of carbon atoms contained in the alkenyl group may be 2 to 10, 2 to 8, 2 to 6, or 2 to 4. In addition, the number of carbon atoms contained in the alkynyl group may be 2 to 10, 2 to 8, 2 to 6, or 2 to 4. In addition, the number of carbon atoms contained in the alkoxy may be 1 to 10, 1 to 8, 1 to 6, 1 to 4, or 1 to 2. In addition, in the above chemical formula 4, d, e, and f may each independently be an integer of 1 to 4, an integer of 1 to 2, or 1. The liquid crystal composition including the compound represented by the above chemical formula 4, wherein the types of substituents satisfy the above, may have excellent optical properties.

[0182] According to one embodiment of the present invention, the nonpolar compound may include a compound represented by the following chemical formula 4-1:

[0183] [Chemical Formula 4-1]

[0184]

[0185] In the above chemical formula 4-1, A1 to A3 are each independently cyclohexane; or benzene; and at least one of A1 to A3 is cyclohexane, and R 41 and R 42 are each independently a straight or branched alkyl group having 1 to 10 carbon atoms; or a straight or branched alkenyl group having 2 to 10 carbon atoms; and R 43 Inland R 45 are each independently hydrogen; or a straight or branched chain alkyl group having 1 to 10 carbon atoms; and when there are multiple of them, they are the same or different, n1 is 0 or 1, and d, e and f are each independently integers from 1 to 4.

[0186] The compound represented by the above chemical formula 4-1 is, compared to the compound represented by the above chemical formula 4, R 41 and R 42 The position of R is fixed, 41 Inland R 45 As the type is specified, the optical properties of the liquid crystal composition including the compound represented by the chemical formula 4-1 can be further improved.

[0187] According to one embodiment of the present invention, the compound represented by the chemical formula 4 may include at least one of the following compounds:

[0188] Compound 4-1 <Compound 4-2>

[0189]

[0190] Compound 4-3 <Compound 4-4>

[0191]

[0192] Compound 4-5 <Compound 4-6>

[0193]

[0194] Compound 4-7 <Compound 4-8>

[0195]

[0196] Compound 4-9

[0197]

[0198] Compound 4-10

[0199] .

[0200] When the compound represented by the above chemical formula 4 includes at least one of the compounds described above, a liquid crystal composition having excellent optical properties such as refractive index anisotropy and dielectric anisotropy can be more easily provided.

[0201] According to one embodiment of the present invention, based on 100 parts by weight of the liquid crystal composition, the content of the compound represented by the chemical formula 4 may be 10 parts by weight or more and 60 parts by weight or less. Specifically, the content of the compound represented by the chemical formula 4 may be 15 parts by weight or more and 55 parts by weight or less, 20 parts by weight or more and 50 parts by weight or less, 25 parts by weight or more and 45 parts by weight or less, 10 parts by weight or more and 45 parts by weight or less, 15 parts by weight or more and 40 parts by weight or less, 20 parts by weight or more and 35 parts by weight or less, 30 parts by weight or more and 60 parts by weight or less, 30 parts by weight or more and 55 parts by weight or less, 35 parts by weight or more and 50 parts by weight or less, or 40 parts by weight or more and 50 parts by weight or less, based on 100 parts by weight of the liquid crystal composition. When the content of the compound represented by the chemical formula 4 is within the above-mentioned range, the liquid crystal composition may have excellent optical properties.

[0202] According to one embodiment of the present invention, the weight ratio of the compound represented by the chemical formula 1 to the compound represented by the chemical formula 4 may be 1:0.5 to 1:20, 1:0.5 to 1:15, 1:1 to 1:10, 1:1 to 1:7.5, 1:1 to 1:5, 1:5 to 1:20, 1:7.5 to 1:15, or 1:10 to 1:15. When the weight ratio of the compound represented by the chemical formula 1 to the compound represented by the chemical formula 4 is within the above-mentioned range, the liquid crystal composition may have excellent optical properties.

[0203] According to one embodiment of the present invention, the weight ratio of the compound represented by the chemical formula 2 to the compound represented by the chemical formula 4 may be 1:0.3 to 1:10, 1:0.3 to 1:7.5, 1:0.3 to 1:5, 1:0.3 to 1:3, 1:0.3 to 1:1.5, 1:3 to 1:10, or 1:5 to 1:10. When the weight ratio of the compound represented by the chemical formula 2 to the compound represented by the chemical formula 4 is within the above-mentioned range, the liquid crystal composition may have excellent optical properties.

[0204] According to one embodiment of the present invention, the polar compound may include a compound represented by the following chemical formula 5:

[0205] [Chemical Formula 5]

[0206]

[0207] In the above chemical formula 5, A4 to A7 are each independently an alicyclic ring having 5 to 10 carbon atoms; or an aromatic ring having 6 to 30 carbon atoms; and R 51 and R 52are each independently a straight or branched alkyl group having 1 to 10 carbon atoms; a straight or branched alkenyl group having 2 to 10 carbon atoms; a straight or branched alkynyl group having 2 to 10 carbon atoms; a straight or branched alkoxy group having 1 to 10 carbon atoms; a halogen group; or a cyano group (-CN); and wherein R 53 Inland R 56 are each independently hydrogen; a straight or branched alkyl group having 1 to 10 carbon atoms; a straight or branched alkenyl group having 2 to 10 carbon atoms; a straight or branched alkynyl group having 2 to 10 carbon atoms; a straight or branched alkoxy group having 1 to 10 carbon atoms; or a halogen group; and R 53 Inland R 56 are each independently, and when there are multiple of them, they are the same or different, and the R 57 is a direct bond; or -CF2O-;, n2 and n3 are each independently 0 or 1, and g, j, k and l are each independently integers from 1 to 4. At this time, when the sum of n2 and n3 is 1, at least one of A4 to A7 is an alicyclic ring having 5 to 10 carbon atoms or R 57 This could be -CF2O-.

[0208] According to one embodiment of the present invention, A4 to A7 may each independently be cyclohexane or benzene. In this case, when the sum of n2 and n3 is 1, at least one of A4 to A7 may be cyclohexane. R of the chemical formula 5 51 Inland R 56In , the number of carbon atoms contained in the alkyl group may be 1 to 10, 1 to 8, 1 to 6, 1 to 4, or 1 to 2. In addition, the number of carbon atoms contained in the alkenyl group may be 2 to 10, 2 to 8, 2 to 6, or 2 to 4. In addition, the number of carbon atoms contained in the alkynyl group may be 2 to 10, 2 to 8, 2 to 6, or 2 to 4. In addition, the number of carbon atoms contained in the alkoxy group may be 1 to 10, 1 to 8, 1 to 6, 1 to 4, or 1 to 2. In addition, the halogen group may be a fluoro group (-F). In addition, in the above chemical formula 5, g, j, k, and l may each independently be an integer of 1 to 4, an integer of 1 to 2, or 1. The liquid crystal composition including the compound represented by the above chemical formula 5, which satisfies the types of substituents described above, may have excellent optical properties.

[0209] According to one embodiment of the present invention, the polar compound may include a compound represented by the following chemical formula 5-1:

[0210] [Chemical Formula 5-1]

[0211]

[0212] In the above chemical formula 5-1, A4 to A7 are each independently cyclohexane; or benzene; and R 51 and R 52 are each independently a straight or branched alkyl group having 1 to 10 carbon atoms; a halogen group; or a cyano group (-CN); and R 53 Inland R 56 are each independently hydrogen; a straight or branched alkyl group having 1 to 10 carbon atoms; or a halogen group; and when there are multiple of them, they are the same or different, and the R 57 is a direct bond; or -CF2O-;, n2 and n3 are each independently 0 or 1, and g, j, k and l are each independently integers from 1 to 4.

[0213] The compound represented by the above chemical formula 5-1 is, compared to the compound represented by the above chemical formula 5, R 51 and R 52 The position of R is fixed, 51 Inland R 56 As the type is specified, the optical properties of the liquid crystal composition including the compound represented by the chemical formula 5-1 can be further improved.

[0214] According to one embodiment of the present invention, the compound represented by the chemical formula 5 may include at least one of the following compounds:

[0215] Compound 5-1 <Compound 5-2>

[0216]

[0217] Compound 5-3 <Compound 5-4>

[0218]

[0219] Compound 5-5

[0220]

[0221] Compound 5-6

[0222]

[0223] Compound 5-7

[0224]

[0225] Compound 5-8

[0226]

[0227] Compound 5-9

[0228] .

[0229] When the compound represented by the above chemical formula 5 includes at least one of the compounds described above, a liquid crystal composition having excellent optical properties such as refractive index anisotropy and dielectric anisotropy can be more easily provided.

[0230] According to one embodiment of the present invention, based on 100 parts by weight of the liquid crystal composition, the content of the compound represented by the chemical formula 5 may be 5 parts by weight or more and 45 parts by weight or less. Specifically, the content of the compound represented by the chemical formula 5 may be 10 parts by weight or more and 40 parts by weight or less, 15 parts by weight or more and 35 parts by weight or less, 20 parts by weight or more and 30 parts by weight or less, 5 parts by weight or more and 30 parts by weight or less, 10 parts by weight or more and 25 parts by weight or less, 10 parts by weight or more and 20 parts by weight or less, 10 parts by weight or more and 15 parts by weight or less, 20 parts by weight or more and 45 parts by weight or less, 25 parts by weight or more and 45 parts by weight or less, or 30 parts by weight or more and 45 parts by weight or less, based on 100 parts by weight of the liquid crystal composition. When the content of the compound represented by the chemical formula 5 is within the above-mentioned range, the liquid crystal composition may have excellent optical properties.

[0231] According to one embodiment of the present invention, the weight ratio of the compound represented by the chemical formula 1 to the compound represented by the chemical formula 5 may be 1:0.5 to 1:15, 1:0.5 to 1:10, 1:1 to 1:7.5, 1:2 to 1:5, 1:0.5 to 1:7.5, or 1:5 to 1:10. When the weight ratio of the compound represented by the chemical formula 1 to the compound represented by the chemical formula 5 is within the above-mentioned range, the liquid crystal composition may have excellent optical properties.

[0232] According to one embodiment of the present invention, the weight ratio of the compound represented by the chemical formula 2 to the compound represented by the chemical formula 5 may be 1:0.1 to 1:10, 1:3 to 1:7.5, 1:1 to 1:5, 1:0.1 to 1:3.5, or 1:5 to 1:10. When the weight ratio of the compound represented by the chemical formula 2 to the compound represented by the chemical formula 5 is within the above-mentioned range, the liquid crystal composition may have excellent optical properties.

[0233] According to one embodiment of the present invention, the refractive index anisotropy of the liquid crystal composition may be 0.15 or more and 0.25 or less, 0.16 or more and 0.24 or less, 0.17 or more and 0.23 or less, 0.18 or more and 0.22 or less, or 0.19 or more and 0.21 or less. The liquid crystal composition satisfying the above-described refractive index anisotropy may have excellent optical properties. Through this, a display element and an optical element with excellent quality and reliability can be easily provided using the liquid crystal composition.

[0234] According to one embodiment of the present invention, the dielectric anisotropy of the liquid crystal composition may be 3 or more and 20 or less, 3 or more and 15 or less, 5 or more and 18 or less, or 5 or more and 15 or less. The liquid crystal composition satisfying the above-described dielectric anisotropy may have excellent optical properties. Through this, display devices and optical devices with excellent quality and reliability can be easily provided using the liquid crystal composition.

[0235] According to one embodiment of the present invention, the liquid crystal composition can satisfy the following mathematical formula 2.

[0236] [Equation 2]

[0237] (DC) / CX 100 < 100 %

[0238] In the above mathematical expression 2, C is the yellow index value of the liquid crystal composition before UV irradiation, and D is the yellow index value of the liquid crystal composition after irradiation with UV having a wavelength of 365 nm and an energy of 3 J.

[0239] That is, the liquid crystal composition may have a change rate of the yellow index calculated by the following mathematical formula 2-1 of less than 100%.

[0240] [Equation 2-1]

[0241] Rate of change of yellow index = (DC) / CX 100

[0242] The liquid crystal composition satisfying the above mathematical formula 2 may have excellent stability against UV. On the other hand, if the liquid crystal composition includes a compound represented by the above chemical formula 3, or includes only a compound represented by the chemical formula 1 and a compound represented by the chemical formula 2, the rate of change in the yellow index may be 100% or more, which may cause a problem of poor stability against UV.

[0243]

[0244] One embodiment of the present invention provides an optical element including the liquid crystal composition.

[0245] An optical element according to one embodiment of the present invention may have excellent optical properties by including the liquid crystal composition.

[0246] According to one embodiment of the present invention, the optical element can be utilized as an optical element in various fields. For example, the optical element can be employed in optical elements such as liquid crystal lenses, liquid crystal prisms, and switching elements that utilize the change in birefringence of liquid crystals. Furthermore, the optical element can be employed in a stereoscopic image display device and a 2D-3D variable image display device.

[0247]

[0248] One embodiment of the present invention provides a display device including the liquid crystal composition.

[0249] A display device according to one embodiment of the present invention can have excellent quality and reliability by including the liquid crystal composition. In addition, the response time required for operation of the display device can be further improved.

[0250] According to one embodiment of the present invention, the display device may include the liquid crystal composition. The display device may employ any configuration used in the art without limitation, except for including the liquid crystal composition. For example, the display device may be a liquid crystal display device employing a TN (Twisted Nematic), STN (Super-Twisted Nematic), or PDLC (Polymer Dispersed Liquid Crystal) mode, which require high birefringence.

[0251] The above optical element and the above display device may employ without limitation any configurations used in the art, except for including the liquid crystal composition.

[0252]

[0253] Hereinafter, the present invention will be described in detail using examples. However, the examples according to the present invention may be modified in various ways, and the scope of the present invention is not limited to the examples described below. The examples in this specification are provided to more fully explain the present invention to those of ordinary skill in the art.

[0254]

[0255] Manufacturing of liquid crystal compositions

[0256] compound

[0257] The following compounds were prepared as compounds represented by chemical formula 1.

[0258] Code structure ACA-2.3 (compound 1-1) ACA-3.3 (compound 1-2) ACA-2.4 (compound 1-3) ACA-4.3 (compound 1-4) ACA-3.CN (compound 1-5) ACA-3.F (compound 1-6) ACE-2.F (compound 1-7) ACE-3.F (compound 1-8) ACA-2.F (compound 1-9)

[0259]

[0260] The following compounds were prepared as compounds represented by chemical formula 2.

[0261] Code structure AMA-1.O2 (compound 2-1) AMA-2.O1 (compound 2-2) AMA-3.O1 (compound 2-3) AMA-3V.3V (compound 2-4) AMA-1.3 (compound 2-5) AMC-3.F (compound 2-6)

[0262]

[0263] The following compounds were prepared as compounds represented by chemical formula 3.

[0264] Code structure EMAA-2.3 (compound 3-1) EMAA-4.3 (compound 3-2) EMAA-5.3 (compound 3-3)

[0265]

[0266] The following compounds were prepared as compounds (non-polar compounds) represented by chemical formula 4.

[0267] Code structure BB-3.V (compound 4-1) BB-3.U1 (Compound 4-2) AA- W.1 (compound 4-3) BA-3.O1 (compound 4-4) BAA-3.2 (compound 4-5) BAA-5.2 (compound 4-6) BBA-V.1 (compound 4-7) BBA-W.1 (compound 4-8) BBA-3.1 (compound 4-9)

[0268]

[0269] The following compounds were prepared as compounds (polar compounds) represented by chemical formula 5.

[0270] Code structure AA-2.CN (compound 5-1) AA-3.CN (Compound 5-2) BA-3.CN (compound 5-3) BAE-3.F (Compound 5-4) BBE-3.F (compound 5-5) AEXE-2.F (compound 5-6) AEXE-3.F (compound 5-7) ACEXE-3.F (compound 5-8) ACEXE-4.F (compound 5-9)

[0271]

[0272] Calculating B / A according to Equation 1-1

[0273] 1) Absorbance measurement for UV

[0274] UV absorbance was measured for the compounds listed in Table 5 of Table 1 above. Specifically, each of the compounds was diluted in a solvent (methylene chloride) to a concentration of 1 ppm to prepare a solution, and the UV absorbance in the wavelength range of 200 nm to 800 nm was measured using a Cary 5000 instrument (Agilent).

[0275]

[0276] 2) B / A calculation

[0277] For the compounds listed in Table 5 of Table 1 above, the value of B / A was obtained using the following mathematical formula 1-1.

[0278] [Mathematical Formula 1-1]

[0279] B / AX 100 (%)

[0280] In the above mathematical expression 1-1, A is the total area of ​​the absorbance curve from the first inflection point to the final inflection point in the absorbance measurement wavelength range, and B is the area of ​​the absorbance curve from the 330 nm point to the final inflection point in the absorbance measurement wavelength range.

[0281] Figures 2a and 2b show the results of UV absorbance measurements for a compound with the code EMAA-2.3.

[0282] Referring to Fig. 2a, it can be seen that the compound EMAA-2.3 (compound 3-1) has an initial inflection point (first inflection point; IP1), a second inflection point (IP2), and a final inflection point (third inflection point; IP3) in the absorbance measurement wavelength range of 200 nm to 400 nm.

[0283] At this time, A of the above mathematical expression 1-1 corresponds to the total area of ​​the absorbance measurement curve from the first inflection point (the first inflection point; IP1) to the final inflection point (the third inflection point; IP3), and was calculated as 14.75. Meanwhile, B of the above mathematical expression 1-1 corresponds to the area of ​​the absorbance curve from the 330 nm point to the final inflection point (the third inflection point; IP3), and was calculated as 1.30. When this was introduced into mathematical expression 1-1, it was calculated as 8.81%.

[0284] Thereafter, the value of B / A was calculated for the compounds listed in Table 5 in Table 1 in the same manner as described above, and the results are shown in Table 6 below.

[0285]

[0286] Code B / AX 100% Chemical Formula 1 ACA-2.3 (Compound 1-1) 0 ACA-3.3 (Compound 1-2) 0 ACA-2.4 (Compound 1-3) 0 ACA-4.3 (Compound 1-4) 0 ACA-3.CN (Compound 1-5) 0 ACA-3.F (Compound 1-6) 0 ACE-2.F (Compound 1-7) 0 ACE-3.F (Compound 1-8) 0 ACA-2.F (Compound 1-9) 0 Chemical Formula 2 AMA-1.O2 (Compound 2-1) 0 AMA-2.O1 (Compound 2-2) 0 AMA-3.O1 (Compound 2-3) 0 AMA-3V.3V (Compound 2-4) 0 AMA-1.3 (Compound 2-5) 0AMC-3.F(Compound 2-6) 0Chemical formula 3EMAA-2.3(Compound 3-1) 8.81EMAA-4.3(Compound 3-2) 9.75EMAA-5.3(Compound 3-3) 8.43Chemical formula 4BB-3.V(Compound 4-1) 0BB-3.U1(Compound 4-2) 0AA-1.W(Compound 4-3) 0BA-3.O1(Compound 4-4) 0BAA-3.2(Compound 4-5) 0BAA-5.2(Compound 4-6) 0BBA-V.1(Compound 4-7) 0BBA-W.1(Compound 4-8) 0BBA-3.1(Compound 4-9) 0Chemical formula 5AA-2.CN(Compound 5-1)0AA-3.CN(Compound 5-2)0BA-3.CN(Compound 5-3)0BAE-3.F(Compound 5-4)0BBE-3.F(Compound 5-5)0AEXE-2.F(Compound 5-6)0AEXE-3.F(Compound 5-7)0ACEXE-3.F(Compound 5-8)0ACEXE-4.F(Compound 5-9)0

[0287]

[0288] Example 1

[0289] Compounds represented by chemical formula 1 and having codes ACA-2.3, ACA-3.3, and ACA-2.4, compounds represented by chemical formula 2 and having codes AMA-1.O2 and AMA-2.O1, compounds represented by chemical formula 4 and having codes BB-3.V, BB-3.U1, BA-3.O1, and BAA-3.2, and compounds represented by chemical formula 5 and having codes AEXE-2.F, AEXE-3.F, BAE-3.F, ACEXE-3.F, and ACEXE-4.F were prepared.

[0290] Afterwards, the above compounds were mixed to prepare a liquid crystal composition. At this time, based on 100 parts by weight of the liquid crystal composition, the content of ACA-2.3 corresponding to the compound represented by chemical formula 1 is 5 parts by weight, the content of ACA-3.3 is 5 parts by weight, the content of ACA-2.4 is 4 parts by weight, the content of AMA-1.O2 corresponding to the compound represented by chemical formula 2 is 3 parts by weight, the content of AMA-2.O1 is 4 parts by weight, the content of BB-3.V corresponding to the compound represented by chemical formula 4 is 20 parts by weight, the content of BB-3.U1 is 10 parts by weight, the content of BA-3.O1 is 3 parts by weight, the content of BAA-3.2 is 8 parts by weight, and the content of AEXE-2.F corresponding to the compound represented by chemical formula 5 is 7 parts by weight, the content of AEXE-3.F is 7 parts by weight, the content of BAE-3.F is 8 parts by weight, and the content of ACEXE-3.F is 8 parts by weight. The content of ACEXE-4.F was 8 parts by weight.

[0291]

[0292] Examples 2 to 19

[0293] As shown in Tables 7 to 13 below, a liquid crystal composition was manufactured in the same manner as in Example 1, except that the types and contents of the compound represented by Chemical Formula 1, the compound represented by Chemical Formula 2, the compound represented by Chemical Formula 4 (non-polar compound), and the compound represented by Chemical Formula 5 (polar compound) contained in the liquid crystal composition were adjusted.

[0294] Code Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Chemical Formula 1 ACA-2.3507433 ACA-3.3507434 ACA-2.4406220 ACA-4.3056000 ACA-3.CN000000 ACA-3.F000000 ACE-2.F000000 ACE-3.F000000 ACA-2.F000000 Chemical Formula 2 AMA-1.O2355567 AMA-2.O1486688 AMA-3.O1066678 AMA-3V.3V095567 AMA-1.3094655 AMC-3.F0180000 Chemical Formula 4 BB-3 .V201011111010BB-3.U11000453AA-1.W000000BA-3.O1300465BAA-3.2806998BAA-5.2000600BBA-V.1050088BBA-W.1000000BBA-3 .10100000Chemical formula5BA-3.CN005700AEXE-2.F706000AEXE-3.F706566BAE-3.F800000BBE-3.F090000ACEXE-3.F837889ACEXE-4.F837889

[0295] In Table 7 above, the contents (parts by weight) of the compound represented by Chemical Formula 1, the compound represented by Chemical Formula 2, the compound represented by Chemical Formula 4, and the compound represented by Chemical Formula 5 are based on 100 parts by weight of the liquid crystal composition.

[0296]

[0297] Code Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Chemical Formula 1 ACA-2.3333370 ACA-3.3223370 ACA-2.4000366 ACA-4.3000006 ACA-3.CN000060 ACA-3.F000007 ACE-2.F000000 ACE-3.F000000 ACA-2.F000007 Chemical Formula 2 AMA-1.O26910755 AMA-2.O18910866 AMA-3.O18910766 AMA-3V.3V7910755 AMA-1.36910744 AMC-3.F0010000 Chemical Formula 4 BB-3.V15120101011BB-3.U1550030AA-1.W000000BA-3.O1340600BAA-3.28810930BAA-5.2006000BBA-V.1538809BBA-W.1000000BBA -3.1000000Formula5BA-3.CN000085AEXE-2.F000004AEXE-3.F600605BAE-3.F000080BBE-3.F000000ACEXE-3.F995887ACEXE-4.F995887

[0298] In Table 8 above, the contents (parts by weight) of the compound represented by Chemical Formula 1, the compound represented by Chemical Formula 2, the compound represented by Chemical Formula 4, and the compound represented by Chemical Formula 5 are based on 100 parts by weight of the liquid crystal composition.

[0299]

[0300] Code Example 13 Example 14 Example 15 Example 16 Example 17 Example 18 19 Chemical Formula 1 ACA-2.30074765 ACA-3.30070750 ACA-2.46060750 ACA-4.36660750 ACA-3.CN0000000 ACA-3.F0600500 ACE-2.F7700000 ACE-3.F7700000 ACA-2.F0000400 Chemical Formula 2 AMA-1.O25504537 AMA-2.O16664537 AMA-3.O16664037 AMA-3V.3V5550007 AMA-1.34400007 AMC-3.F0090006 Chemical Formula 4 BB-3.V 11111119221815BB-3.U10000686AA-1.W0008000BA-3.O10008680BAA-3.200650106BAA-5.20008005BBA-V.199010004BBA-W.10000000BBA-3 .10000000Formula5BA-3.CN5550090AEXE-2.F4460000AEXE-3.F55610550BAE-3.F0000000BBE-3.F0000048ACEXE-3.F7778745ACEXE-4.F7778745

[0301] In Table 9 above, the contents (parts by weight) of the compound represented by Chemical Formula 1, the compound represented by Chemical Formula 2, the compound represented by Chemical Formula 4, and the compound represented by Chemical Formula 5 are based on 100 parts by weight of the liquid crystal composition.

[0302]

[0303] Comparative Example 1

[0304] A compound represented by chemical formula 1 and having the code ACA-2.3, a compound represented by chemical formula 2 and having the code AMA-1.O2, AMA-2.O1, a compound represented by chemical formula 3 and having the code EMAA-2.3, a compound represented by chemical formula 4 and having the code BB-3.V, BB-3.U1, BA-3.O1, BAA-3.2, BBA-V.1, and a compound represented by chemical formula 5 and having the code BA-3.CN, AEXE-3.F, BBE-3.F, ACEXE-3.F, ACEXE-4.F were prepared.

[0305] Afterwards, the above compounds were mixed to prepare a liquid crystal composition. At this time, based on 100 parts by weight of the liquid crystal composition, the content of ACA-2.3 corresponding to the compound represented by chemical formula 1 is 5 parts by weight, the content of AMA-1.O2 corresponding to the compound represented by chemical formula 2 is 5 parts by weight, the content of AMA-2.O1 is 5 parts by weight, the content of EMAA-2.3 corresponding to the compound represented by chemical formula 3 is 5 parts by weight, the content of BB-3.V corresponding to the compound represented by chemical formula 4 is 25 parts by weight, the content of BB-3.U1 is 5 parts by weight, the content of BA-3.O1 is 5 parts by weight, the content of BAA-3.2 is 5 parts by weight, the content of BBA-V.1 is 5 parts by weight, and the content of BA-3.CN corresponding to the compound represented by chemical formula 5 is 10 parts by weight, the content of AEXE-3.F is 5 parts by weight, the content of BBE-3.F is 8 parts by weight, and the content of ACEXE-3.F is 6 parts by weight, the content of ACEXE-4.F was 6 parts by weight.

[0306]

[0307] Comparative Examples 2 to 5

[0308] As shown in Table 10 below, a liquid crystal composition was manufactured in the same manner as in Comparative Example 1, except that the types and contents of the compound represented by Chemical Formula 1, the compound represented by Chemical Formula 2, the compound represented by Chemical Formula 3 (a compound satisfying Chemical Formula 1), the compound represented by Chemical Formula 4 (a non-polar compound), and the compound represented by Chemical Formula 5 (a polar compound) included in the liquid crystal composition were adjusted.

[0309] Code Comparison Example 1 Comparison Example 2 Comparison Example 3 Comparison Example 4 Comparison Example 5 Chemical Formula 1 ACA-2.350300 ACA-3.300300 ACA-2.400000 ACA-4.300000 ACA-3.CN00000 ACA-3.F00000 ACE-2.F00000 ACE-3.F00000 ACA-2.F00000 Chemical Formula 2 AMA-1.O25605 AMA-2.O15604 AMA-3.O100000 AMA-3V.3V00000 AMA-1.300000 AMC-3.F00004 Chemical Formula 3 EMAA-2.355555 EMAA-4.300055 EMAA-5.300005 Chemical Formula 4BB-3.V2522252322BB-3.U158584AA-1.W00800BA-3.O155856BAA-3.258653BAA-5.200300BBA-V.155858BBA-W.100000BBA-3.100000 Chemical Formula 5BA-3.CN101001010AEXE-2.F00500AEXE-3.F55555BAE-3.F00000BBE-3.F88088ACEXE-3.F66866ACEXE-4.F66866

[0310] In Table 10 above, the contents (parts by weight) of the compound represented by Chemical Formula 1, the compound represented by Chemical Formula 2, the compound represented by Chemical Formula 3, the compound represented by Chemical Formula 4, and the compound represented by Chemical Formula 5 are based on 100 parts by weight of the liquid crystal composition.

[0311]

[0312] Experimental example

[0313] 1. Nematic phase-isotropic liquid phase transition temperature (T ni )

[0314] Measurements were conducted using an MP50 device from Mettler Toledo. Specifically, the liquid crystal composition was filled into a capillary tube dedicated to the melting point measuring device, and measurements were made at a rate of 3°C / min to determine the temperature at which a sharp change occurred in the transmittance curve.

[0315]

[0316] 2. Double refraction (refractive index anisotropy, Δn)

[0317] Measurements were conducted using Atago's DR-M4 equipment. Specifically, measurements were made using an Abbe refractometer equipped with a polarizing plate in the eyepiece using light with a wavelength of 589 nm at 20°C. After rubbing the surface of the main prism in one direction, the liquid crystal composition was dropped onto the main prism. Thereafter, the refractive index (ne) when the polarization direction was parallel to the rubbing direction and the refractive index (no) when it was perpendicular to the rubbing direction were measured, and the birefringence (refractive index anisotropy, dn) was calculated using the following equation 1.

[0318] [Formula 1]

[0319] Δn = ne-no

[0320]

[0321] 3. Dielectric anisotropy (Δε)

[0322] Measurements were conducted using Toyo Corporation EC1 equipment. The measured ε∥ and ε⊥ were calculated by substituting them into Equation 2 below.

[0323] [Formula 2]

[0324] Δε = ε∥ - ε⊥

[0325]

[0326] 1) Measurement of dielectric constant ε∥

[0327] A vertical alignment film was formed by applying a vertical alignment agent to the ITO patterned surfaces of two glass substrates. Next, a spacer was applied to one of the two glass substrates so that the vertical 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, a liquid crystal composition was injected into the device and sealed with an adhesive that was cured with ultraviolet light.

[0328] Afterwards, using the EC1 equipment, the voltage was applied from 0 to 20 V in 0.5 V increments at 20°C and measured, and the value (ε∥) of 20 V was measured.

[0329]

[0330] 2) Measurement of dielectric constant ε⊥

[0331] A horizontal alignment agent was applied to the ITO patterned surfaces of two glass substrates to form a horizontal alignment film. Next, a spacer was applied to 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, a liquid crystal composition was injected into the device and sealed with an adhesive that was cured with ultraviolet light.

[0332] Afterwards, using the EC1 equipment of Toyo Corporation, the voltage was applied from 0 to 20 V in 0.5 V increments at 20°C and measured, and the value of 0 V (ε⊥) was measured.

[0333]

[0334] 4. Rotational viscosity (γ1)

[0335] Measurements were made using an LCM2 device from Toyo Corporation. Specifically, a horizontal alignment agent was applied to the ITO patterned surfaces of two glass substrates to form a horizontal alignment film. Next, a spacer was applied to 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 20 μm, and then the two glass substrates were bonded together. Then, a liquid crystal composition was injected into the device and sealed.

[0336] Afterwards, using the above equipment, the rotational viscosity (mPa·s) was measured by applying a voltage of 100 V at 20°C.

[0337]

[0338] 5. Yellow Index (YI)

[0339] 1 g of liquid crystal composition was placed in a 10 ml vial and irradiated with UV at energies of 1 J (1 J = 100 mW X 10 s) and 3 J (3 J = 100 mJ X 30 s) using a HS-C0240-395 UV LED exposure device from Hansol Technics. After diluting the UV-irradiated sample with 4 g of acetone, the yellow index was measured using a SH-7000 spectrophotometer from DENSHOKU at 20 ℃.

[0340] Afterwards, the yellow index (YI) change rate was calculated for the liquid crystal composition according to the following mathematical formula 2-1.

[0341] [Equation 2-1]

[0342] Yellow Index (YI) change rate = (DC) / CX 100 (%)

[0343] In the above mathematical expression 2-1, C is the yellow index value of the liquid crystal composition before UV irradiation, and D is the yellow index value of the liquid crystal composition after irradiation with UV having a wavelength of 365 nm and an energy of 3 J.

[0344]

[0345] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Tni71.951.973.574.573.573.1Δn0.15200.17940.20910.18980.18970.1974ne1.65041.69621.72441.70001.70031.7094no1.49841.51681.51531.510 21.51061.5120Δε10.123.829.177.796.016.65ε∥13.727.1613.0311.339.4110.10ε⊥3.603.343.863.543.403.45γ185.163.2115.997.6106.9109.8YI_0J (C)0.250.260.230.220.240.23YI_3J (D)0.400.460.370.400.400.45YI Change Rate (%)607761826796

[0346] Referring to Table 11 above, in the case of the liquid crystal compositions manufactured in Examples 1 to 6 of the present invention, the clearing point (T ni ), refractive index anisotropy (Δn), and dielectric anisotropy (Δε) were measured to confirm that the optical properties were excellent. In addition, the yellow index (YI) change rate confirmed that the UV stability was excellent.

[0347]

[0348] Example 7 Example 8 Example 9 Example 10 Example 11 Example 12 Tni68.467.573.272.084.774.1Δn0.18800.20240.23600.21040.21640.2038ne1.69761.71801.76201.71481.72981.7180no1.50961.51 561.52601.50441.51341.5142Δε6.564.653.546.0510.849.64ε∥9.947.876.839.4814.5913.50ε⊥3.383.223.293.433.753.86γ196.690.6112.3115.7126.8111.8YI_0J (C)0.220.220.230.210.220.23YI_3J (D)0.390.360.370.410.410.40YI Change rate(%)776461958674

[0349] Referring to Table 12 above, in the case of the liquid crystal compositions manufactured in Examples 7 to 12 of the present invention, the clearing point (T ni ), refractive index anisotropy (Δn), and dielectric anisotropy (Δε) were measured to confirm that the optical properties were excellent. In addition, the yellow index (YI) change rate confirmed that the UV stability was excellent.

[0350]

[0351] Example 13 Example 14 Example 15 Example 16 Example 17 Example 18 Example 19 Tni65.565.365.570.377.974.068.9Δn0.19540.19460.19680.15320.17780.15180.1836ne1.70781.70761.71121.65701.68381.65461.6916no1.51301.51221.51441.5038 1.50601.50281.5080Δε12.0112.629.896.956.075.854.05ε∥16.0916.7613.8910.299.489.317.17ε⊥4.084.144.003.343.413.463.12γ1103.4103.0100.783.097.278.779.5YI_0J (C)0.230.230.220.220.230.210.24YI_3J (D)0.410.360.390.430.410.410.46YI Change rate (%)78577795789592

[0352] Referring to Table 13 above, in the case of the liquid crystal compositions manufactured in Examples 13 to 19 of the present invention, the clearing point (T ni ), refractive index anisotropy (Δn), and dielectric anisotropy (Δε) were measured to confirm that the optical properties were excellent. In addition, the yellow index (YI) change rate confirmed that the UV stability was excellent.

[0353]

[0354] Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Tni70.871.871.875.672.0Δn0.14080.14170.13780.14440.1487ne1.63701.63521.63561.63801.6439no1.49621.49351.49781.49361.4952Δε7.667.717.037.768.50ε∥11.2611.2610.2911.2512.11ε⊥3.603.553.263.493.61γ169.672.073.374.787.0YI_0J (C)0.230.230.220.220.23YI_3J (D)0.470.480.460.620.75YI Change rate (%)104109109182226

[0355] Referring to Table 14 above, in the case of the liquid crystal compositions manufactured in Comparative Examples 1 to 5, the clearing point (T ni ), refractive index anisotropy (Δn), and dielectric anisotropy (Δε) were measured to confirm that the optical properties were inferior to those of the previously described examples. In addition, the UV stability was confirmed to be inferior to those of the previously described examples through the yellow index (YI) change rate.

[0356] In particular, referring to Table 14 above, it was confirmed that the yellow index values ​​of the liquid crystal compositions according to Comparative Examples 4 and 5 changed significantly after 3J UV irradiation compared to before UV irradiation. On the other hand, the yellow index values ​​of the liquid crystal compositions according to Examples 1 to 19 did not change significantly after 3J UV irradiation compared to before UV irradiation, confirming that they had excellent UV stability.

[0357]

[0358] Referring to the experimental data described above, it can be seen that the liquid crystal composition according to one embodiment of the present invention implements excellent optical properties and at the same time, improves UV stability.

Claims

1. A compound represented by the following chemical formula 1; and A compound represented by the following chemical formula 2; Does not include a compound whose absorbance measured for UV satisfies the following mathematical formula 1, Liquid crystal composition with positive dielectric anisotropy: [Chemical Formula 1] [Chemical Formula 2] [Mathematical Formula 1] B / AX 100 ≥ 7.5% In the above chemical formula 1, R1 to R5 are each independently hydrogen; a straight or branched alkyl group having 1 to 10 carbon atoms; a straight or branched alkenyl group having 2 to 10 carbon atoms; a straight or branched alkynyl group having 2 to 10 carbon atoms; a straight or branched alkoxy group having 1 to 10 carbon atoms; a halogen group; or a cyano group (-CN); However, R1 and R2 are not hydrogen at the same time, and R3 to R5 are not hydrogen at the same time. R3 to R5 are each independently, and when there are multiple of them, they are the same or different. n, m and p are each independently integers from 1 to 4, In the above chemical formula 2, R 21 Inland R 24 are each independently hydrogen; a straight or branched alkyl group having 1 to 10 carbon atoms; a straight or branched alkenyl group having 2 to 10 carbon atoms; a straight or branched alkynyl group having 2 to 10 carbon atoms; a straight or branched alkoxy group having 1 to 10 carbon atoms; a halogen group; or a cyano group (-CN); However, R 21 and R 22 is not hydrogen at the same time, R 23 Inland R 24 is not hydrogen at the same time, R 23 Inland R 24 are each independent, and when there are multiple of them, they are the same or different, h and i are each independently integers from 1 to 4, In the above mathematical expression 1, A is the total area of ​​the absorbance curve from the first inflection point to the final inflection point in the absorbance measurement wavelength range, B is the area under the absorbance curve from the 330 nm point to the final inflection point in the absorbance measurement wavelength range.

2. In paragraph 1, The compound represented by the above chemical formula 1 includes a compound represented by the following chemical formula 1-1, A liquid crystal composition comprising a compound represented by the above chemical formula 2 and a compound represented by the following chemical formula 2-1: [Chemical Formula 1-1] [Chemical Formula 2-1] In the above chemical formula 1-1, R1 and R2 are each independently a straight or branched alkyl group having 1 to 5 carbon atoms; a halogen group; or a cyano group (-CN), R3 to R5 are each independently hydrogen; a straight or branched alkyl group having 1 to 5 carbon atoms; a straight or branched alkenyl group having 2 to 5 carbon atoms; a straight or branched alkynyl group having 2 to 5 carbon atoms; a straight or branched alkoxy group having 1 to 5 carbon atoms; or a halogen group; and when there are multiple of them, they are the same or different, and at least one of R3 to R5 is a halogen group, n, m and p are each independently integers from 1 to 4, In the above chemical formula 2-1, R 21 and R 22 are each independently a straight or branched alkyl group having 1 to 5 carbon atoms; a straight or branched alkenyl group having 2 to 5 carbon atoms; a straight or branched alkoxy group having 1 to 5 carbon atoms; a halogen group; or a cyano group (-CN); R 23 and R 24 are each independently hydrogen; a straight or branched alkyl group having 1 to 5 carbon atoms; a straight or branched alkenyl group having 2 to 5 carbon atoms; a straight or branched alkynyl group having 2 to 5 carbon atoms; a straight or branched alkoxy group having 1 to 5 carbon atoms; or a halogen group; and when there are multiple of them, they are the same or different, h and i are each independently integers from 1 to 4.

3. In paragraph 1, The compound represented by the above chemical formula 1 includes a compound represented by the following chemical formula 1-2, A liquid crystal composition comprising a compound represented by the above chemical formula 2, wherein the compound represented by the following chemical formula 2-2: [Chemical Formula 1-2] [Chemical Formula 2-2] In the above chemical formula 1-2, R1 and R2 are each independently a straight or branched alkyl group having 1 to 5 carbon atoms; a halogen group; or a cyano group (-CN), R3 and R5 are each independently hydrogen; a straight or branched alkyl group having 1 to 5 carbon atoms; or a halogen group; and when there are multiple R3 and R5, they are the same or different. R4 is a halogen group, n and p are each independently integers from 1 to 4, In the above chemical formula 2-2, R 21 and R 22 are each independently a straight or branched alkyl group having 1 to 5 carbon atoms; a straight or branched alkenyl group having 2 to 5 carbon atoms; a straight or branched alkoxy group having 1 to 5 carbon atoms; a halogen group; or a cyano group (-CN); R 23 is hydrogen; a straight or branched alkyl group having 1 to 5 carbon atoms; or a halogen group; and when there are multiple of them, they are the same or different, R 24 is hydrogen; or a halogen group; h is an integer from 1 to 4.

4. In paragraph 1, A liquid crystal composition in which, in the above chemical formula 1, at least one of R1 and R2 is a straight or branched alkyl group having 1 to 10 carbon atoms; or a cyano group.

5. In paragraph 1, A liquid crystal composition in which at least one of R3 to R5 in the above chemical formula 1 is a fluoro group (-F).

6. In paragraph 1, In the above chemical formula 2, R 21 and R 22 A liquid crystal composition, wherein at least one of the groups is a straight or branched alkoxy group having 1 to 5 carbon atoms.

7. In paragraph 1, A liquid crystal composition comprising at least one of the following compounds, wherein the compound represented by the above chemical formula 1: Compound 1-1 Compound 1-2 Compound 1-3 <Compound 1-4> Compound 1-5 <Compound 1-6> Compound 1-7 Compound 1-8 Compound 1-9 .

8. In paragraph 1, A liquid crystal composition comprising at least one of the following compounds, wherein the compound represented by the above chemical formula 2: Compound 2-1 <Compound 2-2> Compound 2-3 <Compound 2-4> Compound 2-5 <Compound 2-6> .

9. In paragraph 1, A liquid crystal composition wherein the sum of the content of the compound represented by the chemical formula 1 and the content of the compound represented by the chemical formula 2 is 16 parts by weight or more, based on 100 parts by weight of the liquid crystal composition.

10. In paragraph 1, A liquid crystal composition in which the weight ratio of the compound represented by the above chemical formula 1 and the compound represented by the above chemical formula 2 is 1:0.2 to 1:

10.

11. In paragraph 1, A liquid crystal composition, wherein the compound satisfying the above mathematical formula 1 contains three or more aromatic rings having 6 to 30 carbon atoms and at least one alkynylene bond connecting adjacent aromatic rings.

12. In paragraph 1, A liquid crystal composition having a refractive index anisotropy of 0.15 or more and 0.25 or less.

13. In paragraph 1, A liquid crystal composition having a dielectric anisotropy of 3 or more and 15 or less.

14. In paragraph 1, The above liquid crystal composition is a liquid crystal composition that satisfies the following mathematical formula 2: [Equation 2] (DC) / CX 100 < 100 % In the above mathematical expression 2, C is the yellow index value of the liquid crystal composition before UV irradiation, and D is the yellow index value of the liquid crystal composition after irradiation with UV having a wavelength of 365 nm and an energy of 3 J.

15. An optical element comprising a liquid crystal composition according to paragraph 1.

16. A display device comprising a liquid crystal composition according to paragraph 1.

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