Liquid crystal dielectric applicable to high-frequency electromagnetic wave modulation, and component thereof

1. A liquid-crystalline medium applicable to high-frequency electromagnetic wave modulation, wherein the liquid-crystalline medium having a clearing point of more than 110° C., a low-temperature storage temperature of below −20° C., and an optical anisotropy of more than 0.35, the liquid-crystalline medium comprising:

one or more compounds selected from the compounds of general Formula I in an amount of 30-80% of the total weight of the liquid-crystalline medium:

one or more compounds selected from the compounds of general Formula II and/or general Formula III in an amount of 20-70% of the total weight of the liquid-crystalline medium:

in which,

R 1 , R 2 , R 3 , R 4 , R 5 , R 6 and R 7 each independently represents C 1-12 alkane group,

one or more than two nonadjacent —CH 2 — in the alkane group can each be independently replaced by —CH═CH—, —C≡C—, —O—, —CO—, —CO—O— or —O—CO—, and one or more —H present in these groups can each be independently substituted by —F or —Cl; and

X 1 , X 2 , X 3 , X 4 and X 5 each independently represents —H, —F or —OCF 3 , and at least two of X 1 , X 2 and X 3 represents —F; and

one or more compounds selected from a group consisting of the following compounds:

in which,

R 81 represents C 4-10 alkane group or alkoxyl group; and

L 1 and L 2 each independently represents —H or —F.

2. A liquid-crystalline medium according to claim 1 , wherein R 1 and R 2 each independently selected from a group consisting of —C 2 H 5 , —C 3 H 7 , —C 4 H 9 and —C 5 H 11 .

3. A liquid-crystalline medium according to claim 1 , wherein the compound of general Formula II is selected from a group consisting of the following compounds:

in which,

R 31 and R 41 each independently represents C 2-6 alkane group,

4. A liquid-crystalline medium according to claim 1 , wherein the compound of general Formula III is selected from a group consisting of the following compounds:

in which,

R 51 and R 61 each independently represents C 2-6 alkane group,

and

R 71 represents C 1-5 alkane group,

5. A liquid-crystalline medium according to claim 1 , wherein the liquid-crystalline medium can further comprise one or more compounds selected from the compounds of general Formula V:

in which,

R 10 and R 11 each independently represents C 1-12 alkane group, alkoxyl group, alkenyl group or alkenyloxy group;

Z 2 represents single bond, —CF 2 O—, —OCF 2 —, —CO—O—, —O—CO— or —CH 2 CH 2 —; and

n represents 0 or 1.

6. A liquid-crystalline medium according to claim 5 , wherein the compound of general Formula V is selected from a group consisting of the following compounds:

wherein R 10 and R 11 each independently represents C1-12 alkane group, alkoxyl group, alkenyl group or alkenyloxy group.

7. A liquid-crystalline medium according to claim 1 , wherein the liquid-crystalline medium further comprises one or more additives.

8. A component for high-frequency technology, comprising the liquid-crystalline medium of claim 1 .