LIQUID CRYSTAL COMPOSITION AND ITS APPLICATION

Abstract

The present invention provides a novel liquid crystal material composition comprising one or more compound, in order to achieve the properties of low viscosity, high resistivity, good low-temperature mutual solubility, fast response, excellent transmission, and which can be used for a variety of fast response display modes. Since the working temperature of a LCD material is subjected to the temperature range of individual LC molecules, information can only be displayed in a specific temperature range of the specific liquid crystal macro-alignment phase. At low temperature, the viscosity of liquid crystal increases exponentially, which in turn substantially reduces the response speed and overall performances of the display system. The liquid crystal composition according to the present invention overcomes these problems with balanced chemical composition by achieving low viscosity, good low-temperature performance and excellent transmission in a wide range of LCD applications including TN, IPS or FFS displays, thus improving display performance.

Claims

1-11. (canceled)

12. A liquid crystal composition for LCD device comprising: a) 1 to 90 weight percents of one or more compounds represented by the general formula I; b) 1 to 85 weight percents of one or more compounds represented by the general formula II to III; c) at most 80% of one or more compounds represented by the general formula IV to XIII; d) at most 30 weight percents of one or more compounds represented by the general formula XIV to XVI; e) at most 30 weight percents of one or more compounds represented by the general formula XVII to XXI; f) at most 15% of one or more compounds represented by the general formula XXII to XXV; wherein the above a) to f) sum to 100%;
R-A.sub.1-Z.sub.1-A.sub.2-Z.sub.2-A.sub.3-Z.sub.3-A.sub.4-Z.sub.4-A.sub.5-O(CH.sub.2)nF  I wherein, R is selected from H and unsubstituted or substituted alkyl or alkoxy containing 1 to 12 carbon atoms, one or more CH.sub.2 groups thereof being independently replaced by —C≡C—, —CF.sub.2O—, —CH═CH—, —O—, —CO—O—, —O—CO— in a manner of not directly being bonded each other to oxygen atoms, and one or more H atoms thereof being replaced by halogen; A.sub.1, A.sub.2, A.sub.3, A.sub.4 and A.sub.5 are each independently selected from: a single bond; 1,3-cyclopentylene, 1,4-cyclohexylene, 1,4-cyclohexenyl; 1,4-piperidine group; 1,4-bicyclo [2.2.2] octyl; 1,4-phenylene, naphthalene-2,6-diyl; trans-decalin-2,6-diyl; tetrahydronaphthalene-2,6-diyl; indan; indene; phenanthrenyl and dibenzofuran; wherein 1,4-cyclohexylene, one or two nonadjacent CH.sub.2 thereof being replaced by O or S; 1,4-phenylene, one or two nonadjacent CH being replaced by N; and hydrogen may independently be substituted with halogen in each case; while A.sub.1, A.sub.2, A.sub.3, A.sub.4 and A.sub.5 cannot be all a single bond; Z.sub.1, Z.sub.2, Z.sub.3 and Z.sub.4 are each independently selected from: a single bond, —(CH.sub.2).sub.2—, —(CH.sub.2).sub.4—, —CH═CHCH.sub.2CH.sub.2—, —CH.sub.2CH.sub.2CH═CH—, CF.sub.2O, OCF.sub.2, CF.sub.2CF.sub.2, CF═CF, CH.sub.2CF.sub.2, CF.sub.2CH.sub.2, OCF.sub.2CF.sub.2O, C.sub.2H.sub.4CF.sub.2O, CH.sub.2CF.sub.2OCH.sub.2, CH.sub.2OCF.sub.2CH.sub.2, OCF.sub.2C.sub.2H.sub.4, C.sub.3H.sub.6O, OC.sub.3H.sub.6, C.sub.2H.sub.4OCH.sub.2, CH.sub.2OC.sub.2H.sub.4, CH.sub.2O, OCH.sub.2, —CH═CH—, —C≡C— and COO; n is 2, 3 or 4; ##STR00050## ##STR00051## ##STR00052## wherein, R.sub.2 and R.sub.3 are each independently selected from: alkyl or alkoxy containing 1-7 carbon atoms, one or more CH.sub.2 groups thereof may each, independently be replaced by —CH═CH— and one or more H atoms thereof may be replaced by fluorine element; A and B are each independently selected from 1,4-cyclohexylene; 1,4-phenylene, one or more H atoms thereof may also be replaced by fluorine element; C and D are each independently selected from 1,4-cyclohexylene, one or two nonadjacent —CH.sub.2— thereof may be replaced by O; Y.sub.1-Y.sub.7 each independently denotes H or F; Z.sub.5 denotes a single bond, —C.sub.2H.sub.4—, —(CH.sub.2).sub.4—, —CH═CH, —CF═CF, —C.sub.2F.sub.4—, —CH.sub.2CF.sub.2—, —CF.sub.2CH.sub.2—, —CH.sub.2O—, —OCH.sub.2, —COO—, —CF.sub.2O— or —OCF.sub.2—; X.sub.1 denotes F, OCF.sub.3, OCHF.sub.2, CF.sub.3, CF.sub.2H, Cl, OCH═CF.sub.2 or OCF.sub.2CF═CF.sub.2.

13. The liquid crystal composition according to claim 12, wherein the composition comprises the following components: a) 2 to 55 weight percents of one or more compounds represented by the general formula I; b) 17 to 82 weight percents of one or more compounds represented by the general formula II to III; c) at most 57 weight percents of one or more compounds represented by the general formula IV to XIII; d) at most 30 weight percents of one or more compounds represented by the general formula XIV to XVI; e) at most 26 weight percents of one or more compounds represented by the general formula XVII to XXI; wherein the above a) to e) sum to 100%.

14. The liquid crystal composition according to claim 13, wherein the composition comprises the following components: a) 3 to 50 weight percents of one or more compounds represented by the general formula I; b) 20 to 80 weight percents of one or more compounds represented by the general formula II to III; c) 5 to 50 weight percents of one or more compounds represented by the general formula IV to XIII; d) 1 to 15 weight percents of one or more compounds represented by the general formula XIV to XVI; e) 1 to 25 weight percents of one or more compounds represented by the general formula XVII to XXI; wherein the above a) to e) sum to 100%.

15. The liquid crystal composition according to claim 14, wherein the composition comprises the following components: a) 5 to 50 weight percents of one or more compounds represented by the general formula I; b) 20 to 60 weight percents of one or more compounds represented by the general formula II to III; c) 10 to 50 weight percents of one or more compounds rep represented by the general formula IV to XIII; d) 3 to 15 weight percents of one or more compounds represented by the general formula XIV to XVI; e) 3 to 20 weight percents of one or more compounds represented by the general formula XVII to XXI; wherein the above a) to e) sum to 100%; or a) 10 to 38 weight percents of one or more compounds represented by the general formula I; b) 23 to 42 weight percents of one or more compounds represented by the general formula II to III; c) 34 to 45 weight percents of one or more compounds represented by the general formula IV to a XIII; d) 0 to 12 weight percents of one or more compounds represented by the general formula XIV to XVI; e) 0 to 8 weight percents of one or more compounds represented by the general formula XVII to XXI; wherein the above a) to e) sum to 100%; or a) 28 to 46 weight percents of one or more compounds represented by the general formula I; b) 23 to 56 weight percents of one or more compounds represented by the general formula II to III; c) 0 to 20 weight percents of one or more compounds represented by the general formula IV to a XIII; d) 8 to 14 weight percents of one or more compounds represented by the general formula XIV to XVI; e) 8 to 19 weight percents of one or more compounds represented by the general formula XVII to XXI; wherein the above a) to e) sum to 100%; or a) 15 to 41 weight percents of one or more compounds represented by the general formula I; b) 20 to 42 weight percents of one or more compounds represented by the general formula II to III; c) 22 to 33 weight percents of one or more compounds represented by the general formula IV to XIII; d) 14 to 30 weight percents of one or more compounds represented by the general formula XIV to XVI; e) 3 to 24 weight percents of one or more compounds represented by the general formula XVII to XXI; wherein the above a) to e) add up to 100%.

16. The liquid crystal composition according to claim 15, wherein the compound is represented by the general formula I, wherein: R is selected from H and unsubstituted or substituted alkyl or alkoxy containing 1 to 7 carbon atoms, one or more CH.sub.2 groups thereof independently being replaced by —CH═CH—, —O—, in a manner of not directly being bonded each other to oxygen atoms, and one or more H atoms thereof being replaced by halogen; A.sub.1, A.sub.2, A.sub.3, A.sub.4 and A.sub.5 are each independently selected from: a single bond; 1,3-cyclopentylene, 1,4-cyclohexylene, 1,4-cyclohexenyl; 1,4-phenylene, naphthalene-2,6-diyl; trans-decalin-2,6-diyl; tetrahydronaphthalene-2,6-diyl; indan; 1,4-cyclohexylene, one or two CH.sub.2 nonadjacent thereof being replaced by O or S; 1,4-phenylene one or two CH nonadjacent being replaced by N; and hydrogen may independently be substituted with halogen in each case; while A.sub.1, A.sub.2, A.sub.3, A.sub.4 and A.sub.5 cannot be all a single bond; Z.sub.1, Z.sub.2, Z.sub.3 and Z.sub.4 are each independently selected from: a single bond, —(CH.sub.2).sub.2—, —(CH.sub.2).sub.4—, CF.sub.2O, OCF.sub.2, CF═CF, CH.sub.2CF.sub.2, CF.sub.2 CH.sub.2, CH.sub.2O, OCH.sub.2, —CH═CH—; n is 2, 3 or 4; wherein, R is more preferably selected from H and unsubstituted or substituted alkyl or alkoxy each containing 1 to 6 carbon atoms, one or more CH.sub.2 groups thereof being each independently replaced by —CH═CH—, —O—, in a manner of not directly bonded to oxygen atoms, and one or more H atoms thereof being replaced by fluorine; A.sub.1, A.sub.2, A.sub.3, A.sub.4 and A.sub.5 are each independently selected from a single bond; 1,4-cyclohexylene; 1,4-cyclohexenyl; 1,4-phenylene; 1,4-cyclohexylene, one or two CH.sub.2 nonadjacent thereof being replaced by oxygen; and one or more hydrogen thereof may independently be substituted by fluorine in each case; while A.sub.1, A.sub.2, A.sub.3, A.sub.4 and A.sub.5 cannot be all a single bond; Z.sub.1, Z.sub.2, Z.sub.3 and Z.sub.4 are each independently selected from: a single bond, —(CH.sub.2).sub.2—, CF.sub.2O; n is 2, 3 or 4.

17. The liquid crystal composition according to claim 15, wherein the composition comprises compounds represented by the general formula I selected from the compounds represented by one or more of: ##STR00053## ##STR00054## ##STR00055## ##STR00056## ##STR00057## wherein, R.sub.1 is selected from alkyl or alkoxy group containing 1 to 6 carbon atoms, one or more CH.sub.2 groups thereof being independently replaced by —CH═CH—, one or more hydrogen atom thereof being replaced by fluorine; n is 2, 3 or 4.

18. The liquid crystal composition according to claim 15, the composition comprising the compound represented by the general formal I is listed as follows: ##STR00058## ##STR00059## ##STR00060## ##STR00061## ##STR00062## ##STR00063## ##STR00064## ##STR00065## ##STR00066## ##STR00067## ##STR00068## ##STR00069##

19. The composition according to claim 12, wherein the compound formula II and/or Ill are represented by at least one compound selected from the following: ##STR00070## ##STR00071##

20. The composition according to claim 12, wherein the compound formula IV to XIII is represented by at least one compound selected from the following: ##STR00072## ##STR00073## ##STR00074## ##STR00075## ##STR00076## wherein, R.sub.2 and X.sub.1 denotes the same as in claim 12, Y.sub.1-Y.sub.7 each independently denote H or F.

21. The composition according to claim 12, wherein the compound of formula XIV to XVI is represented by at least one compound selected from the following: ##STR00077## wherein, R.sub.2, R.sub.3, Y.sub.1, Y.sub.2 and X.sub.1 represent the same as in claim 12 respectively.

22. The liquid crystal composition according to claim 12, wherein the compound of formula XVII to XXI is represented by at least one compound selected from the following: ##STR00078## ##STR00079## wherein, R.sub.2, R.sub.3 and X.sub.1 represent the same as in claim 12 respectively.

23. The liquid crystal composition according to claim 12, wherein the compound of formula XXII to XXV is represented by at least one compound selected from the following: ##STR00080## wherein, R.sub.2 and R.sub.3 represent the same as in claim 12 respectively.

24. The liquid crystal composition according to claim 12, wherein the LCD device means TN, ADS, FFS or IPS display.

Description

DETAILED DESCRIPTION

[0077] The following examples illustrate the embodiment of the invention but the applicants do not intend to limit the scope of the present invention.

[0078] The embodiment of the invention for preparing the liquid crystal compositions is described as follows:

[0079] To prepare a homogeneous liquid crystal solution, a well-known thermo dissolution approach in the field was introduced: firstly, weight the liquid crystal compounds on the weighting scales; secondly, mixing the liquid crystal compounds without specific sequential requirement, but usually in order of higher melting point first; thirdly, stir the compounds at 60-100 C, such that the components melted uniformly. After filtration, rotary evaporation and packaging, the final target sample is obtained.

[0080] Unless otherwise indicated, percentages are by weight and temperatures are given in degrees Celsius in the contest. The following abbreviations are used:

Δn is optical anisotropy (20° C.), Δ∈ dielectric anisotropy (25° C., 1000 Hz), γ.sub.1 for the bulk viscosity (mPa.Math.s, 25° C.), Cp is the clearing point of liquid crystal composition (° C.). For ease of illustration, in the following examples, the group structure of the liquid crystal compound is represented by the code shown in Table 1:

TABLE-US-00001 TABLE 1 The group structure and the code of the liquid crystal compound Group structure Code Name of group [00035] C 1,4-cyclohexylene [00036] P 1,4-phenylene [00037] G 2-fluoro-1,4-phenylene [00038] U 2,6-difluoro-1,4-phenylene [00039] W 2,3-difluoro-1,4-phenylene [00040] A 2,5-tetrahydropyran [00041] D 2,6-dioxane-1,4-bis oxetanyl —O— O oxygen substituent —F F Fluoro substituent —OCH.sub.2CH.sub.2F O2F 2-fluoro-ethoxy —OCH.sub.2CH.sub.2CH.sub.2F O3F 3-fluoropropoxy —OCF.sub.3 OCF3 trifluoromethoxy —OCF.sub.2H OCF2H difluoromethoxy —CF.sub.3 CF3 trifluoromethyl —Cl Cl chlorine CH.sub.2CH.sub.2 2 ethyl bridge —CF.sub.2O— Q difluoromethoxy bridge —OCHF.sub.2 OCHF2 Difluoromethoxy —CH═CH— V Alkenyl group C≡C T alkynyl

[0081] The following structure, as an example,

##STR00042##

can be represented as CDUQU-3.O3F.

[0082] The following structure, as another example,

##STR00043##

can be represented as CCPU-5.F.

[0083] The following examples describe in detail the percentage ratio of the liquid crystal compounds prepared according the present invention and the performance parameters of the resulting liquid crystal composition as shown in the following tables.

Example 1

[0084] Table 2 Percentage of component and performance parameters of the liquid crystal composition of Example 1

TABLE-US-00002 Component wt % Perameter Value CPU-3.O2F 3 Δn 0.112 CPU-3.O3F 3 Δε +5.0 PUQU-3.O2F 6 γ.sub.1 (mPa .Math. s) 65.0 PUQU-3.O3F 6 Cp (° C.) 75 PUQU-5.O2F 6 PUQU-5.O3F 5 PGUQU-3.O3F 6 CCP-V.1 4 CCP-V2.1 3 CC-3.V 40 CC-3.V1 3 PGP-2.3 5 PGP-2.4 5 PGP-3.5 5

[0085] The composition has a low viscosity, which is suitable for fast response LCD device.

Example 2

[0086] Table 3 percentage of component and performance parameters of the liquid crystal composition of Example 2

TABLE-US-00003 Component wt % Perameter Value CPU-3.O2F 3 Δn 0.112 CPU-3.O3F 3 Δε +5.0 PUQU-3.O2F 6 γ.sub.1 (mPa .Math. s) 65.0 PUQU-3.O3F 6 Cp (° C.) 75 PUQU-5.O2F 6 PUQU-5.O3F 5 PGUQU-3.O3F 6 CCP-V.1 4 CCP-V2.1 3 CC-3.V 40 CC-3.V1 3 PGP-2.3 5 PGP-2.4 5 PGP-3.5 5

[0087] The composition has a high dielectric anisotropy, low viscosity, which is suitable for fast response and low driving voltage LCD device.

Example 3

[0088] Table 4 percentage of component and performance parameters of the liquid crystal composition of Example 3

TABLE-US-00004 Component wt % Perameter Value CPU-3.O2F 5 Δn 0.100 CPU-3.O3F 5 Δε +5.0 PUQU-3.O2F 6 γ.sub.1 (mPa .Math. s) 77 PUQU-3.O3F 6 Cp (° C.) 91.0 PUQU-5.O2F 6 PUQU-5.O3F 6 DUQU-4.O3F 3 CCPU-3.O3F 1 CCP-V.1 14 CC-3.V 35 CC-3.V1 5 CPPC-3.3 4 CGPC-3.3 4

[0089] The composition has a high dielectric anisotropy, low viscosity, which is suitable for fast response and low driving voltage LCD device.

Example 4

[0090] Table 5 percentage of component and performance parameters of the liquid crystal composition of Example 4

TABLE-US-00005 Component wt % Perameter Value CPU-3.O2F 5 Δn 0.099 CPU-3.O3F 4 Δε +8.0 CCU-3.O2F 3 γ.sub.1 (mPa .Math. s) 87 CCU-3.O3F 4 Cp (° C.) 92.0 PUQU-3.O2F 5 PUQU-3.O3F 5 PUQU-5.O3F 5 PGUQU-3.O3F 2 DUQU-3.O3F 4 DUQU-4.O3F 5 DPUQU-4.O3F 4 CCPU-2.O3F 3 CCPU-3.O3F 3 CCPU-5.O3F 3 CCP-V.1 6 CC-3.V 33 CC-3.V1 3 CCP-3.OCF3 3

[0091] The composition has a high dielectric anisotropy, which is suitable for low driving voltage LCD device.

Example 5

[0092] Table 6 percentage of component and performance parameters of the liquid crystal composition of Example 5

TABLE-US-00006 Component wt % Perameter Value CPU-3.O2F 3 Δn 0.099 CPU-3.O3F 3 Δε +8.3 PUQU-3.O3F 4 γ.sub.1 (mPa .Math. s) 92 PUQU-5.O3F 4 Cp (° C.) 93.0 PGUQU-3.O3F 3 PGUQU-5.O3F 3 DUQU-3.O3F 8 DUQU-4.O3F 9 DPUQU-4.O3F 4 CCPU-3.O3F 4 CCPU-5.O3F 4 CCP-V.1 11 CC-3.V 30 CC-3.2V1 6 CCP-3.OCF3 4

[0093] The composition has a high dielectric anisotropy, which is suitable for low driving voltage LCD device.

Example 6

[0094] Table 7 percentage of component and performance parameters of the liquid crystal composition of Example 6

TABLE-US-00007 Component wt % Perameter Value PUQU-3.O3F 3 Δn 0.101 PUQU-5.O3F 2 Δε +9.1 PGUQU-3.O3F 2 γ.sub.1 (mPa .Math. s) 105 CC-3.V 25 Cp (° C.) 91.0 CCU-2.F 7 CCU-3.F 14 CGU-2.F 12 CGU-3.F 11 CGPC-3.3 3 CCPU-2.F 3 CCPU-3.F 8 CCPU-4.F 4 CCGU-3.F 6

[0095] The composition has a high dielectric anisotropy, which is suitable for low driving voltage LCD device.

Example 7

[0096] Table 8 percentage of component and performance parameters of the liquid crystal composition of Example 7

TABLE-US-00008 Component wt % Perameter Value PGU-3.O3F 6 Δn 0.105 CC-3.V 25 Δε +7.9 CCU-2.F 11 γ.sub.1 (mPa .Math. s) 121 CCU-3.F 14 Cp (° C.) 95.0 CGPC-3.3 3 CPU-5.F 5 CGU-2.F 15 CCPU-2.F 3 CCPU-3.F 8 CCPU-4.F 4 CCGU-3.F 6

Example 8

[0097] Table 9 percentage of component and performance parameters of the liquid crystal composition of Example 8

TABLE-US-00009 Component wt % Perameter Value PGU-3.O3F 5 Δn 0.111 APU-3.O3F 5 Δε +6.9 PUQU-3.O3F 4 γ.sub.1 (mPa .Math. s) 111 PGUQU-3.O3F 5 Cp (° C.) 105.0 CC-3.V 30 CC-3.V1 10 CCP-V.1 3 CPG-3.F 3 CCU-3.F 2 CCPU-3.F 6 CCPU-5.F 6 CCGU-3.F 5 PGUQU-5.F 6 CCQU-3.F 6 CCQU-5.F 4

Example 9

[0098] Table 10 percentage of component and performance parameters of the liquid crystal composition of Example 9

TABLE-US-00010 Component wt % Perameter Value PGU-3.O3F 8 Δn 0.112 APU-3.O3F 9 Δε +2.2 PUQU-3.O3F 10 γ.sub.1 (mPa .Math. s) 80.0 CC-3.V 38 Cp (° C.) 86.0 CC-3.V1 10 CCP-V.1 3 CCP-V2.1 9 PGP-2.3 5 PGP-3.5 5 CGPC-3.3 3

[0099] The composition has a high optical anisotropy and low rotational viscosity, which is suitable for fast response LCD device.

Example 10

[0100] Table 11 percentage of component and performance parameters of the liquid crystal composition of Example 10

TABLE-US-00011 Component wt % Perameter Value PGU-3.O3F 2 Δn 0.098 CC-3.V 33 Δε +7.5 CCU-2.F 10 γ.sub.1 (mPa .Math. s) 95 CCU-3.F 10 Cp (° C.) 94.0 CPU-5.F 6 CGU-2.F 7 CGU-3.F 6 CCPU-2.F 6 CCPU-3.F 7 CCPU-4.F 7 CCGU-3.F 6

Example 11

[0101] Table 12 percentage of component and the performance parameters of the liquid crystal composition of Example 11

TABLE-US-00012 Component wt % Perameter Value PUQU-3.O3F 8 Δn 0.099 CC-3.V 15 Δε +9.0 CCP-V.1 7 γ.sub.1 (mPa .Math. s) 125 CCU-2.F 7 Cp (° C.) 96.0 CCU-3.F 7 CCU-5.F 7 CPPC-3.3 3 CPU-3.F 7 CPU-5.F 8 CCPU-3.F 2 CCPU-5.F 2 CCGU-3.F 6 CCQU-3.F 8 CCQU-5.F 8 CUQU-3.F 5

Example 12

[0102] Table 13 percentage of component and performance parameters of the liquid crystal composition of Example 12

TABLE-US-00013 Component wt % Perameter Value PGU-3.O3F 8 Δn 0.119 APU-3.O3F 8 Δε +9.0 CC-5.V 13 γ.sub.1 (mPa .Math. s) 150 CC-3.V1 4 Cp (° C.) 110.0 CPU-3.F 23 CCG-2.F 3 CCG-3.F 3 CCG-5.F 3 CCPU-2.F 4 CCPU-3.F 4 CCPU-4.F 4 CCPU-5.F 4 CCQU-3.F 19

Example 13

[0103] Table 14 percentage of component and performance parameters of the liquid crystal composition of Example 13

TABLE-US-00014 Component wt % Perameter Value PGU-3.O3F 5 Δn 0.119 PUQU-3.O3F 7 Δε +4.8 CC-3.V 44 γ.sub.1 (mPa .Math. s) 65 CCP-V.1 9 Cp (° C.) 82.0 PGP-2.3 7 PGP-2.4 6 CPP-3.2 7 APUQU-2.F 7 APUQU-3.F 8

Example 14

[0104] Table 15 percentage of component and performance parameters of the liquid crystal composition of Example 14

TABLE-US-00015 Component wt % Perameter Value PGU-3.O3F 7 Δn 0.107 APU-3.O3F 3 Δε +7.0 CC-3.V 33 γ.sub.1 (mPa .Math. s) 87 CC-3.V1 10 Cp (° C.) 96.0 CGU-3.F 5 CCPU-3.F 3 CCPU-5.F 5 CCGU-3.F 5 CCP-3.OCF3 7 CCP-5.OCF3 9 PGUQU-3.F 5 PGUQU-5.F 4 PUQU-3.F 4

Example 15

[0105] Table 16 percentage of component and performance parameters of the liquid crystal composition of Example 15

TABLE-US-00016 Component wt % Perameter Value DUQU-3.O3F 10 Δn 0.110 CCG-V.F 5 Δ∈ +9.2 CC-5.V 14 γ.sub.1 (mPa .Math. s) 125 CC-3.V1 8 Cp(° C.) 96.0 PGP-2.4 8 CPPC-3.3 3 CCPU-2.F 4 CCPU-3.F 5 CCGU-3.4 5 CCP-3.OCF3 5 CCP-5.OCF3 5 CCU-3.OCHF2 10 CUQU-3.F 10 PUQU-3.F 8

Example 16

[0106] Table 17 percentage of component and performance parameters of the liquid crystal composition of Example 16

TABLE-US-00017 Component wt % Perameter Value APU-3.O3F 5 Δn 0.138 PUQU-3.O3F 10 Δ∈ +8.9 PGUQU-3.O3F 4 γ.sub.1 (mPa .Math. s) 135 CC-3.V 20 Cp(° C.) 97.0 PGP-2.3 5 PGP-2.4 4 PGP-3.5 3 CPU-3.F 9 CGU-2.F 10 CGU-3.4 8 CCPU-2.F 4 CCPU-3.F 8 CCPU-4.F 4 CCGU-3.F 6

Example 17

[0107] Table 18 percentage of component and performance parameters of the liquid crystal composition of Example 17

TABLE-US-00018 Component wt % Perameter Value DUQU-3.03F 5 Δn 0.095 PGUQU-3.O3F 6 Δ∈ +2.0 CC-3.V 43 γ.sub.1 (mPa .Math. s) 42 CC-3.V1 12 Cp(° C.) 75.0 PP-1.2V 7 CCP-V.1 10 CCP-V2.1 10 PGP-2.3 7

Example 18

[0108] Table 19 percentage of component and performance parameters of the liquid crystal composition of Example 18

TABLE-US-00019 Component wt % Perameter Value PUQU-3.O3F 15 Δn 0.102 CC-3.V 43 Δ∈ +7.0 CCP-V.1 10 γ.sub.1 (mPa .Math. s) 77 PPGU-3.F 2 Cp(° C.) 86.0 CCP-3.OCF3 10 CPGU-3.OCF3 10 APUQU-2.F 10

Example 19

[0109] Table 20 percentage of component and performance parameters of the liquid crystal composition of Example 19

TABLE-US-00020 Component wt % Perameter Value PGU-3.O3F 10 Δn 0.134 CC-3.V 48 Δ∈ +2.0 CC-3.V1 9 γ.sub.1 (mPa .Math. s) 65 PGP- 1.2V 10 Cp(° C.) 82.0 PGP-2.2V 10 PGP-3.2V 10 PGUQU-3.F 3

Example 20

[0110] Table 21 percentage of component and performance parameters of the liquid crystal composition of Example 20

TABLE-US-00021 Component wt % Perameter Value PGU-3.O3F 4 Δn 0.102 APU-3.O3F 9 Δ∈ +5.3 CC-3.V 27 γ.sub.1 (mPa .Math. s) 90 CC-3.V1 5 Cp(° C.) 98.0 CCP-V.1 13 CCP-V2.1 11 CCG-V.F 6 CCU-3.F 4 CGU-3.F 7 CCGU-3.F 7 PUQU-3.F 7

Example 21

[0111] Table 22 percentage of component and performance parameters of the liquid crystal composition of Example 21

TABLE-US-00022 Component wt % Perameter Value APU-3.O3F 6 Δn 0.100 PUQU-3.O3F 8 Δ∈ +6.0 DUQU-3.O3F 8 γ.sub.1 (mPa .Math. s) 108 PGUQU-3.O3F 6 Cp(° C.) 85.6 APUQU-3.O3F 4 CUQU-3.O3F 9 CC-3.V 30 CC-3.V1 6 CCP-V.1 11 CCP-3.OCF3 4 CCPU-2.F 4 CCPU-3.F 4

Example 22

[0112] Table 23 percentage of component and performance parameters of the liquid crystal composition of Example 22

TABLE-US-00023 Component wt % Perameter Value PUQU-3.O3F 15 Δn 0.106 DUQU-3.O3F 9 Δ∈ +5.8 PGUQU-3.O3F 2 γ.sub.1 (mPa .Math. s) 102 APUQU-3.O3F 4 Cp(° C.) 87.9 CCU-3.O3F 7 CPU-3.O3F 9 CC-3.V 33 CC-3.V1 3 CCP-V.1 6 CCP-3.OCF3 3 CCPU-2.F 3 CCPU-3.F 3 CCPU-4.F 3

Example 23

[0113] Table 24 percentage of component and performance parameters of the liquid crystal composition of Example 23

TABLE-US-00024 Component wt % Perameter Value PUQU-3.O3F 12 Δn 0.115 PGUQU-3.O3F 10 Δ∈ +4.8 CC-3.V 45 γ.sub.1 (mPa .Math. s) 80 PGP-2.3 10 Cp(° C.) 82.0 PGP-2.4 4 CCU-3.F 10 CCPU-2.F 3 CCPU-3.F 3 CCPU-4.F 3

Example 24

[0114] Table 25 percentage of component and performance parameters of the liquid crystal composition of Example 24

TABLE-US-00025 Component wt % Perameter Value PUQU-3.O3F 16 Δn 0.101 APUQU-3.O3F 14 Δ∈ +8.4 CC-3.V 24 γ.sub.1 (mPa .Math. s) 125 CCP-V.1 9 Cp(° C.) 100.0 CCU-2.F 5 CCU-3.F 10 CCP-3.OCF3 5 CPGU-3.OCF3 4 CCQU-3.F 13

[0115] The composition has a relatively high clearing point, which is suitable for increasing working temperature range of the LCD.

Example 25

[0116] Table 26 percentage of component and performance parameters of the liquid crystal composition of Example 25

TABLE-US-00026 Component wt % Perameter Value DUQU-3.O3F 13 Δn 0.112 CCU-3.O3F 5 Δ∈ +11.2 CPU-3.O3F 10 γ.sub.1 (mPa .Math. s) 125 CC-3.V 24 Cp(° C.) 90.0 CCP-V.1 9 CCP-3.OCF3 5 CPGU-3.OCF3 4 CCPU-2.F 4 PUQU-3.F 12 APUQU-3.F 14

[0117] The composition has a very high dielectric anisotropy, which is suitable for low driving voltage LCD device.

Example 26

[0118] Table 27 percentage of component and performance parameters of the liquid crystal composition of Example 26

TABLE-US-00027 Component wt % Perameter Value PUQU-3.O3F 6 Δn 0.106 PGUQU-3.O3F 7 Δ∈ +5.8 APUQU-3.O3F 5 γ.sub.1 (mPa .Math. s) 115 AUQU-3.O3F 5 Cp(° C.) 110.0 CC-3.V 34 CC-3.V1 5 CCP-V.1 10 CCU-3.F 3 CPPC-3.3 4 CCPU-4.F 3 CCP-3.OCF3 3 CCP-5.OCF3 3 CCGU-3.F 5 CPGU-3.OCF3 7

[0119] The composition has a relatively high clearing point, which is suitable for increasing working temperature range of the LCD.

Example 27

[0120] Table 28 percentage of component and performance parameters of the liquid crystal composition of Example 27

TABLE-US-00028 Component wt % Perameter Value DUQU-3.O3F 13 Δn 0.102 CCU-3.O3F 5 Δ∈ +9.8 CPU-3.O3F 10 γ.sub.1 (mPa .Math. s) 102 CC-3.V 24 Cp(° C.) 88.0 CCP-V.1 9 CCW-3.O2 9 CPGU-3.OCF3 4 CCPU-2.F 4 PUQU-3.F 12 APUQU-3.F 10

[0121] The composition has a relatively high dielectric anisotropy. Due to the addition of the monomer with negative dielectric anisotropy, it will remarkably improve the transmittance of LCD.

Comparative Example 1

[0122] Table 29 liquid crystal composition and performance parameters without addition of formula I

TABLE-US-00029 Component wt % Perameter Value CCU-3.F 15 Δn 0.095 CC-3.V 43 Δ∈ +5.5 CCP-V.1 10 γ.sub.1 (mPa .Math. s) 75 PPGU-3.F 2 Cp(° C.) 85.0 CCP-3.OCF3 10 CPGU-3.OCF3 10 APUQU-2.F 10

[0123] Compared the example 18 with the comparative Example 1, the only difference is that the former utilizes PUQU-3.O3F to replace the latter's CCU-3.F and the rest components are remaining unchanged. One may notice that after addition of compound of formula I, the optical anisotropy gains from 0.095 to 0.102, and the dielectric anisotropy from 5.5 to 7.0 while other properties essentially remain the same. As a result, the display driving voltage is decreased and the response speed is increased.

Comparative Example 2

[0124] Table 30 the percentage of component and performance parameters of the liquid crystal composition for TFT display

TABLE-US-00030 Component wt % Perameter Value CCG-2.F 13 Δn 0.0991 CCG-3.F 14 Δ∈ +4.8 CCG-4.F 12 γ.sub.1 (mPa .Math. s) 119 CCG-5.F 10 Cp(° C.) 79.5 3CPG-3.F 9 CPG-4.F 6 CPG-5.F 13 CP-7.F 4 CCU-2.OCF2H 3 CPU-3.F 2 PTG-2.F 2 CP-5.Cl 7 CP-3.O1 5

[0125] Compared with the TFT liquid crystal composition introduced in comparative Example 2, the compositions of the present invention are of significantly higher dielectric anisotropy and lower viscosity γ.sub.1, thereby reduce the driving voltage, viscosity as well as power consumption of the system, while improve the response speed.

[0126] It is concluded that the above embodiments of the present invention is based on the special task for TN, ADS, FFS or IPS display medium. Specifically, the liquid crystal medium not only has a fast response time, a low rotational viscosity and a high birefringence but also has a high clearing point and a suitable dielectric anisotropy.

[0127] In addition, except where noted (some compounds of formula I), liquid crystal compounds wherein the liquid crystal composition used in the present invention, are known substances, and its structure and availability (either commercially available or synthesis) are well-known in the prior art. Due to space constraints, herein the applicant only introduces the preparation of a compound as shown in Example 28.

Example 28

[0128] ##STR00044##

PGUQU-3.O3F (Compound 3) Synthesis

[0129] Synthesis of 1) Onium Trifluoromethyl Sulfonate (Compound 2)

##STR00045##

[0130] 137 g 3,5,2′-trifluoro-4″-propyl-[1,1′; 4′,1″] terphenyl-4-carboxylic acid (Compound 1), 47 mL 1,3-propanedithiol, 42 mL trifluoromethanesulfonic acid, 145 mL of toluene and 145 mL isooctane were added into a 1 L three-necked flask with a water separator mounted at one side opening. The reactants were heated to reflux for 6 hours, slowly cooled down to 0° C., and the product was subject to suction filtration to obtain a solid. The solid was dried for further feeding.

[0131] 2) Synthesis of 4-{[3,5-difluoro-4-(3-fluoro-propoxy)-phenoxy]-methyl}-3,5-difluoro-difluoro-4′-propyl biphenyl (compound 3)

##STR00046##

[0132] 200 mL of methylene chloride, 39 ml triethylamine and 57.7 g 3,5-difluoro-4-(3-fluoro-propoxy)-phenol (Compound 2) were added into 2 L three-necked flask, cooled to 20° C., added with a solution composed of 142 g onium trifluoromethyl sulfonate (compound 2) and 400 mL of methylene chloride and stirred for 1 hour. Then 77 g hydrogen fluoride triethylamine was added dropwise at −75° C., stirring was continued for 1 hour. The temperature was controlled below −75° C., a solution composed of 15 mL bromine and 30 mL of methylene chloride was re-warmed to −10° C. and subjected to post-processing. 1 L of water was added into a 10 L bucket, the stirring was started, the reaction solution was poured and stirred for minutes, solid sodium bicarbonate was added slowly (a large amount of gas was generated) until the PH value of the solution was nearly neutral, standing for liquid separation, the aqueous phase was extracted once with 500 ml dichloromethane, the organic phases were combined, and the solvent was spin-dried at 70° C. to give a solid, recrystallization was carried out with 2-fold ethanol and 1-fold toluene for three times and the suction-filtration and air-drying were performed to obtain a white solid. Theoretical production: 139.2 g, actual production: 144.1 g, a yield of 82.0%.

Gas chromatographic (GC) purity: 99.9%,

[0133] Melting point: 80.2° C.,

[0134] clearing point: 170.2° C.

[0135] Δn: 0.200,

[0136] Δ∈: 21.0

[0137] γ1: 245 mPa.Math.s.

[0138] Mass spectrometry fragmentation: 173,346,375,580 (molecular ion peak);

[0139] NMR spectrum H-NMR (CDCl3,300 mhZ): δH: 0.90-2.60 (m, 9H), 3.90-4.10 (m, 4H), 6.10-7.30 (m, 11H).

[0140] According to the embodiment of the technical solution of example 28, the simple replacement of a raw material containing the corresponding group of the following compounds can be synthesized by those skilled in the art, so there is no specific limitation in the present invention:

##STR00047## ##STR00048## ##STR00049##

[0141] Although general explanations and specific embodiments have been described in detail in the present invention, it is obvious to a person skilled in the art that some modifications or improvements could be made based upon the present invention. Therefore, all these modifications or improvements without departing from the spirit of the invention might belong to the scope claimed in the invention.

INDUSTRIAL APPLICABILITY

[0142] The liquid crystal composition of the present invention has characteristics of low viscosity, high resistivity, good low-temperature mutual solubility, fast response and excellent transmission, which can be used for a variety of fast response display modes. The working temperature of a LCD is subject to the temperature range of liquid crystal. Information can only be displayed in a specific temperature range of liquid crystal phase. At low temperature, the viscosity of liquid crystal increases exponentially, a hurdle of LCD, which substantially reduces the response speed and overall performances of LCD. The liquid crystal composition according to the present invention overcomes these problems. Characterized by its low viscosity, good low-temperature performance and excellent transmission, the liquid crystal composition is applicable in TN, IPS or FFS displays with remarkably improved performances.