LIQUID CRYSTAL COMPOSITION WITH HIGH REFRACTIVE INDEX AND DISPLAY DEVICE THEREOF

Abstract

The present invention provides a liquid crystal composition, comprising, 14-30% of one or more compounds of general Formula I, 8-30% of one or more compounds of general Formula II, 13-58% of one or more compounds of general Formula III, and 20-65% of one or more compounds of general Formula IV, on the basis of the total weight of the liquid crystal composition. The liquid crystal composition of the present invention has a higher retardation, a higher transmittance, a larger optical anisotropy, a proper clearing point, a lower rotational viscosity and a good low-temperature storage stability, and is applicable to liquid crystal display devices to meet the rapid response required by a liquid crystal display, and ensure good display of the liquid crystal display in a harsh environment.

##STR00001##

Claims

1. A liquid crystal composition comprising: one or more compounds of general Formula I ##STR00040## one or more compounds of general Formula II ##STR00041## one or more compounds of general Formula III ##STR00042## one or more compounds of general Formula IV ##STR00043## in which, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 each independently represents H, C.sub.1-C.sub.10 linear or branched alkyl or alkoxy, or C.sub.2-C.sub.10 alkenyl or alkenoxy; ##STR00044## each independently represents ##STR00045## wherein, one or more CH.sub.2 on ##STR00046## can be replaced by O, one or more H on ##STR00047## can be substituted by F; X represents H or F; X.sub.1 represents F or CH.sub.2CH.sub.2CHCF.sub.2; X.sub.2 represents F, CF.sub.3, OCF.sub.3 or OCF.sub.2CFCF.sub.2; L.sub.1 and L.sub.2 are same or different, and each independently represents H or F; m represents 1, 2 or 3; and wherein, when m does not represent 1, ##STR00048## can be same or different.

2. The liquid crystal composition according to claim 1, wherein the compound of general Formula I provides 14-30% of the total weight of the liquid crystal composition; the compound of general Formula II provides 8-30% of the total weight of the liquid crystal composition; the compound of general Formula III provides 13-58% of the total weight of the liquid crystal composition; and the compound of general Formula IV provides 20-65% of the total weight of the liquid crystal composition.

3. The liquid crystal composition according to claim 1, wherein the compound of general Formula I is one or more compounds selected form a group consisting of the following compounds: ##STR00049## wherein, R.sub.1A represents C.sub.1-C.sub.7 linear or branched alkyl or alkoxy.

4. The liquid crystal composition according to claim 1, wherein the compound of general Formula II is one or more compounds selected form a group consisting of the following compounds: ##STR00050## ##STR00051##

5. The liquid crystal composition according to claim 1, wherein the compound of general Formula III is one or more compounds selected from a group consisting of the following compounds: ##STR00052## ##STR00053## ##STR00054## ##STR00055##

6. The liquid crystal composition according to claim 1, wherein the compound of general Formula IV is one or more compounds selected from a group consisting of the following compounds: ##STR00056##

7. The liquid crystal composition according to claim 3, wherein the compound of general Formula I-1 is one or more compounds selected from a group consisting of the following compounds: ##STR00057## and the compound of general Formula I-2 is one or more compounds selected from a group consisting of the following compounds: ##STR00058##

8. The liquid crystal composition according to claim 2, wherein the compound of general Formula I provides 14-25% of the total weight of the liquid crystal composition; the compound of general Formula II provides 8-20% of the total weight of the liquid crystal composition; the compound of general Formula III provides 14.5-35% of the total weight of the liquid crystal composition; and the compound of general Formula IV provides 35-60% of the total weight of the liquid crystal composition.

9. The liquid crystal composition according to claim 8, wherein the compound of general Formula I provides 14-20% of the total weight of the liquid crystal composition; the compound of general Formula II provides 8.5-16% of the total weight of the liquid crystal composition; the compound of general Formula III provides 14.5-20% of the total weight of the liquid crystal composition; and the compound of general Formula IV provides 45-55% of the total weight of the liquid crystal composition

10. The liquid crystal composition according to claim 1, wherein the liquid crystal composition further comprises one or more additives.

11. A liquid crystal display device comprising the liquid crystal composition of claim 1.

Description

DETAILED EMBODIMENTS

[0057] The present invention will be illustrated by combining the detailed embodiments below. It should be noted that, the following examples are exemplary embodiments of the present invention, which are only used to illustrate the present invention, not to limit it. Other combinations and various modifications within the conception of the present invention are possible without departing from the subject matter and scope of the present invention.

[0058] For the convenience of the expression, the group structures of the liquid crystal compositions in the following Examples are represented by the codes listed in Table 1:

TABLE-US-00001 TABLE 1 Codes of the group structures of the liquid crystal compounds Unit structure of group Code Name of the group [00034] C 1,4-cyclohexylidene [00035] P 1,4-phenylene [00036] G 2-fluoro-1,4-phenylene [00037] U 2,5-difluoro-1,4-phenylene [00038] I indan-2,5-diyl F F fluorine substituent CHCH V alkenyl CF.sub.2O Q difluoro ether group OCF.sub.3 OCF3 trifluoromethoxy CF.sub.3 CF3 trifluoromethyl CHCF.sub.2 V(2F) 1,1-difluorovinyl C.sub.2H.sub.4 2 ethylene C.sub.nH.sub.2n+1 or C.sub.mH.sub.2m+1 n or m alkyl

[0059] Take the compound with the following structural formula as an example:

##STR00039##

[0060] Represented by the codes listed in Table 1, this structural formula can be expressed as nCPUF, in which, n in the code represents the number of the carbon atoms of the alkyl group on the left, for example, n is 3, meaning that the alkyl is C.sub.3H.sub.7; C in the code represents cyclohexyl.

[0061] The abbreviated codes of the test items in the following Examples are represented as follows:

[0062] Cp (): clearing point (nematic-isotropy phases transition temperature)

[0063] n: optical anisotropy (589 nm, 25 )

[0064] n.Math.d: retardation amount (mm)

[0065] d: thickness of the liquid crystal layer (m)

[0066] : response time (ms)

[0067] 1: rotational viscosity (mPa*s, at 25 )

[0068] t-.sub.30: low-temperature storage time (at 30 )

[0069] wherein, the optical anisotropy is tested and obtained by using abbe refractometer under sodium lamp (589 nm) light source at 25 .

[0070] The response time is tested by the tester DMS505 at 25 ; the test cell is the left-handed TN type, the cell gap is 3.7 m, and the driving voltage is 5.5 V.

[0071] 1 is tested and obtained by the TOY06254 type liquid crystal physical property evaluation system; the test temperature is 25 , and the test voltage is 90 V.

Comparative Example 1

[0072] The liquid crystal composition of Comparative Example 1 is prepared according to each compound and weight percentage listed in Table 2 and then tested for performance by filling the same between two substrates of a liquid crystal display device. The test data is shown in the Table below:

TABLE-US-00002 TABLE 2 Formulation of the liquid crystal composition and its test performances Code of Compound Test results for the component No. Content, % performance parameters 3CGPC3 II-8 4 Cp 95 3CPUF 18 n 0.116 5CPUF 9 n .Math. d 0.40 3CCP1 3 d 3.5 3CCV IV-7 35 8 3CCV1 IV-8 10 1 73 2PGPC3 II-12 4 t.sub.30 7 d 3PGPC2 II-13 5 3PGPF I-1-2 2 5PGPF I-1-4 3 3PGUQPOCF3 III-21 7 Total 100

Example 1

[0073] The liquid crystal composition of Example 1 is prepared according to each compound and weight percentage listed in Table 3 and then tested for performance by filling the same between two substrates of a liquid crystal display device. The test data is shown in the Table below:

TABLE-US-00003 TABLE 3 Formulation of the liquid crystal composition and its test performances Code of Compound Test results for the component No. Content, % performance parameters 3CPPC3 II-3 2.5 Cp 90 3CGPC3 II-8 2 n 0.129 3CC2 IV-1 6 n .Math. d 0.477 3CCV IV-7 28 d 3.7 4CC3 IV-4 8 7.6 3CCV1 IV-8 7 1 69 2PGPC3 II-12 5 t.sub.30 7 d 3PGPC2 II-13 6 2PGP2V(2F) I-2-1 7 3PGP2V(2F) I-2-2 6 5PGPF I-1-4 7 2IUQUF III-1 4 3IUQUF III-2 7.5 3PGUQUF III-13 4 Total 100

Example 2

[0074] The liquid crystal composition of Example 2 is prepared according to each compound and weight percentage listed in Table 4 and then tested for performance by filling the same between two substrates of a liquid crystal display device. The test data is shown in the Table below:

TABLE-US-00004 TABLE 4 Formulation of the liquid crystal composition and its test performances Code of Compound Test results for the component No. Content, % performance parameters 3CPPC3 II-3 2.5 Cp 92 3CGPC3 II-8 2 n 0.131 3CCV IV-7 43 n .Math. d 0.484 3CCV1 IV-8 10 d 3.7 2PGPC3 II-12 3.5 7.5 3PGPC2 II-13 4 1 72 3PGPF I-1-2 7 t.sub.30 7 d 4PGPF I-1-3 6 5PGPF I-1-4 7 3IUQUF III-2 5 3PGUQUF III-13 4 2PGUQPOCF3 III-20 3 3PGUQPOCF3 III-21 3 Total 100

Example 3

[0075] The liquid crystal composition of Example 3 is prepared according to each compound and weight percentage listed in Table 5 and then tested for performance by filling the same between two substrates of a liquid crystal display device. The test data is shown in the Table below:

TABLE-US-00005 TABLE 5 Formulation of the liquid crystal composition and its test performances Code of Compound Test results for the component No. Content, % performance parameters 3CPPC3 II-3 2.5 Cp 90 3CGPC3 II-8 2.5 n 0.131 5PP1 V-4 9 n .Math. d 0.484 3CC2 IV-1 10 d 3.7 3CCV IV-7 29 7.3 3CCV1 IV-8 7 1 71 2PGPC3 II-12 5 t.sub.30 7 d 3PGPC2 II-13 6 3PGPF I-1-2 5 4PGPF I-1-3 4 3PGP2V(2F) I-2-2 5 3IUQUF III-2 5 3PGUQUF III-13 4 2PGUQPOCF3 III-20 3 3PGUQPOCF3 III-21 3 Total 100

Example 4

[0076] The liquid crystal composition of Example 4 is prepared according to each compound and weight percentage listed in Table 6 and then tested for performance by filling the same between two substrates of a liquid crystal display device. The test data is shown in the Table below:

TABLE-US-00006 TABLE 6 Formulation of the liquid crystal composition and its test performances Code of Compound Test results for the component No. Content, % performance parameters 3CPPC3 II-3 2.5 Cp 92 3CGPC3 II-8 2 n 0.130 5PP1 V-4 4.5 n .Math. d 0.481 3CCV IV-7 42 d 3.7 3CCV1 IV-8 9 7.2 2PGPC3 II-12 2.5 1 71 3PGPC2 II-13 3 t.sub.30 7 d 3PGPF I-1-2 7 4PGPF I-1-3 6 5PGPF I-1-4 7 3PGUQUF III-13 3 5PGUQUF III-15 3 2PGUQPOCF3 III-20 3 3PGUQPOCF3 III-21 3 4PGUQPOCF3 III-22 2.5 Total 100

Example 5

[0077] The liquid crystal composition of Example 5 is prepared according to each compound and weight percentage listed in Table 7 and then tested for performance by filling the same between two substrates of a liquid crystal display device. The test data is shown in the Table below:

TABLE-US-00007 TABLE 7 Formulation of the liquid crystal composition and the its performances Code of Compound Test results for the component No. Content, % performance parameters 3CPPC3 II-3 3 Cp 94 3CGPC3 II-8 3 n 0.133 5PP1 V-4 1.5 n .Math. d 0.478 3CCV IV-7 41 d 3.6 4CC3 IV-4 9.5 7.2 2PGPC3 II-12 2.5 1 73 3PGPC2 II-13 2 t.sub.30 7 d 3PGPF I-1-2 7 4PGPF I-1-3 6 4PGP2V(2F) I-2-3 7 3PGUQUF III-13 3.5 5PGUQUF III-15 3.5 2PGUQPOCF3 III-20 3 3PGUQPOCF3 III-21 4 4PGUQPOCF3 III-22 3.5 Total 100

Example 6

[0078] The liquid crystal composition of Example 6 is prepared according to each compound and weight percentage listed in Table 8 and then tested for performance by filling the same between two substrates of a liquid crystal display device. The test data is shown in the Table below:

TABLE-US-00008 TABLE 8 Formulation of the liquid crystal composition and its test performances Code of Compound Test results for the component No. Content, % performance parameters 3CPPC3 II-3 2.5 Cp 92 3CGPC3 II-8 2 n 0.130 5PP1 V-4 3.5 n .Math. d 0.481 3CCV IV-7 41 d 3.7 3CCV1 IV-8 9.5 7 2PGPC3 II-12 2 1 70 3PGPC2 II-13 2 t.sub.30 7 d 3PGPF I-1-2 7 4PGPF I-1-3 6 5PGPF I-1-4 7 3PGUQUF III-13 3.5 5PGUQUF III-15 3.5 2PGUQPOCF3 III-20 3 3PGUQPOCF3 III-21 4 4PGUQPOCF3 III-22 3.5 Total 100

[0079] As can be known from the test performance parameters of the liquid crystal compositions in Comparative Example 1 and Examples 1-6, the synergies between the components enable the liquid crystal composition of the present invention with a significantly higher retardation amount, a larger optical anisotropy value, a lower rotational viscosity, and a good low-temperature storage stability. Meanwhile, the liquid crystal composition comprising compounds of general Formulas I, II, III and IV, which is screened by a large number of experiments, has proper clearing point and good reliability, and is suitable for the liquid crystal display of AM-TFT display mode, IPS display mode, and the like. A large number of inventive experimental adjustments for the different ratios of the compounds of general Formulas I, II, III, IV ensure that the liquid crystal display comprising the liquid crystal composition of the present invention is capable of meeting the need for rapid response at different temperatures.

INDUSTRIAL APPLICABILITY

[0080] The liquid crystal composition can be applied to the field of liquid crystal.