Liquid crystal composition and display device thereof

Abstract

The present invention provides a liquid crystal composition comprising: at least one compound of general Formula I; at least one compound of general Formula II; at least one compound of general Formula M and at least one compound of general Formula N. The present invention also provides a liquid crystal display device comprising the liquid crystal composition. The liquid crystal composition provided in the present invention has a higher optical anisotropy, a higher clearing point, a higher dielectric anisotropy, a high transmittance and a larger average elastic constant. When the liquid crystal composition is used in the IPS liquid crystal display device, the transmittance of the display device can be effectively improved, so that the display device has a good display performance while also having good energy-saving and environment-friendly characteristics. ##STR00001## ##STR00002## ##STR00003## ##STR00004##

Claims

1. A liquid crystal composition comprising: (a) at least one compound selected from the group consisting of: ##STR00097## in which, L.sub.5 represents —H or —F; R.sub.x and R.sub.y each independently represents —CH.sub.2— or —O—; and n1 represents 0 or 1; (b) at least one compound of general Formula II ##STR00098## (c) at least one compound of general Formula N ##STR00099## and (d) at least one compound of general Formula M ##STR00100## in which, R.sub.1 represents C.sub.1-12 linear or branched alkyl, one or more nonadjacent —CH.sub.2— in the C.sub.1-12 linear or branched alkyl can each be independently replaced by —C═C—, —C≡C—, —O—, —CO—, —CO—O— or —O—CO—, and one or more —H in the C.sub.1-12 linear or branched alkyl can each be independently substituted by —F or —Cl; R.sub.A1 represents C.sub.1-12 linear or branched alkyl, ##STR00101##  one or more nonadjacent —CH.sub.2— in the C.sub.1-12 linear or branched alkyl can each be independently replaced by —CH═CH—, —C≡C—, —O—, —CO—, —CO—O— or —O—CO—, and one or more —H in these groups can each be independently substituted by —F or —Cl; R.sub.N1 and R.sub.N2 each independently represents C.sub.1-12 linear or branched alkyl or alkoxy, or C.sub.2-12 linear or branched alkenyl or alkenoxy, one or more nonadjacent —CH.sub.2— in the C.sub.1-12 linear or branched alkyl or alkoxy, or the C.sub.2-12 linear or branched alkenyl or alkenoxy can each be independently replaced by —C≡C—, —O—, —CO—, —CO—O— or —O—CO—; R.sub.M1 and R.sub.M2 each independently represents —H, —F, ##STR00102##  C.sub.1-12 linear or branched halogenated or unhalogenated alkyl or alkoxy, or C.sub.2-12 linear or branched halogenated or unhalogenated alkenyl or alkenoxy, one or more nonadjacent —CH.sub.2— in the C.sub.1-12 linear or branched halogenated or unhalogenated alkyl or alkoxy, or the C.sub.2-12 linear or branched halogenated or unhalogenated alkenyl or alkenoxy can each be independently replaced by —C≡C—, —O—, —CO—, —CO—O— or —O—CO—; ring ##STR00103##  and ring ##STR00104##  each independently represents ##STR00105##  wherein one or more —CH.sub.2— in ##STR00106##  can be replaced by —O—, and one or more single bonds in the ring can be replaced by double bond; one or more —H on ##STR00107##  can be substituted by —CN, —F or —Cl, and one or more —CH═ in the ring can be replaced by —N═; ring ##STR00108##  and ring ##STR00109##  each independently represents ##STR00110##  wherein one or more —CH.sub.2— in ##STR00111##  can be replaced by —O—, and one or more single bonds in the ring can be replaced by double bond; one or more —H on ##STR00112##  can be substituted by —CN, —F or —Cl, and one or more —CH═ in the ring can be replaced by —N═; ring ##STR00113##  ring ##STR00114##  and ring ##STR00115##  each independently represents ##STR00116##  wherein, at most one —CH.sub.2— in ##STR00117##  can be replaced by —O—, at most one —H on ##STR00118##  can be substituted by halogen; Z.sub.A11 represents single bond, —CH.sub.2CH.sub.2—, —CF.sub.2CF.sub.2—, —CF.sub.2O—, —OCF.sub.2—, —CO—O—, —O—CO—, —O—CO—O—, —CH═CH—, —C≡C—, —CF═CF—, —CH.sub.2O— or —OCH.sub.2—; Z.sub.M1 and Z.sub.M2 each independently represents single bond, —CO—O—, —O—CO—, —CH.sub.2O—, —OCH.sub.2—, —CH═CH—, —C≡C—, —CH.sub.2CH.sub.2— or —(CH.sub.2).sub.4—; Z.sub.N1 and Z.sub.N2 each independently represents single bond, —CO—O—, —O—CO—, —CH.sub.2O—, —OCH.sub.2—, —CH═CH—, —C≡C—, —CH.sub.2CH.sub.2—, —(CH.sub.2).sub.4—, —CF.sub.2O—, —OCF.sub.2— or —CF.sub.2CF.sub.2—; L.sub.1, L.sub.2, and L.sub.4 each independently represents —H, —CH.sub.3 or halogen; X represents halogen, C.sub.1-5 halogenated alkyl or halogenated alkoxy, or C.sub.2-5 halogenated alkenyl or halogenated alkenoxy; L.sub.A11, L.sub.A12 and L.sub.A13 each independently represents —H, —F, —CH.sub.3 or —Cl; X.sub.A1 represents halogen, C.sub.1-5 halogenated alkyl or halogenated alkoxy, or C.sub.2-5 halogenated alkenyl or halogenated alkenoxy; n.sub.A1 represents 0, 1, 2 or 3, and when n.sub.A1=2 or 3, ring ##STR00119##  can be same or different, Z.sub.A11 can be same or different; n.sub.M1 represents 0, 1, 2 or 3, and when n.sub.M1=2 or 3, ring ##STR00120##  can be same or different, Z.sub.M2 can be same or different; and n.sub.N1 represents 0, 1, 2 or 3, n.sub.N2 represents 0 or 1, and 0≤n.sub.N1+n.sub.N2≤3; when n.sub.N1=2 or 3, ring ##STR00121##  can be same or different, and Z.sub.N1 can be same or different.

2. The liquid crystal composition according to claim 1, wherein the at least one compound of Formulas I-3, I-7, and I-8 is 0.1%-60% by weight of the total weight of the liquid crystal composition.

3. The liquid crystal composition according to claim 1, wherein R.sub.A1 represents C.sub.1-8 linear or branched alkyl or alkoxy, or C.sub.2-8 linear or branched alkenyl or alkenoxy.

4. The liquid crystal composition according to claim 1, wherein ring ##STR00122## and ring ##STR00123## each independently represents ##STR00124##

5. The liquid crystal composition according to claim 1, wherein the compound of general Formula II is 1%-75% by weight of the total weight of the liquid crystal composition.

6. The liquid crystal composition according to claim 1, wherein R.sub.N1 and R.sub.N2 each independently represents C.sub.1-8 linear or branched alkyl or alkoxy, or C.sub.2-8 linear or branched alkenyl or alkenoxy; ring ##STR00125## and ring ##STR00126## each independently represents ##STR00127##

7. The liquid crystal composition according to claim 6, wherein the compound of general Formula N is selected form a group consisting of the following compounds: ##STR00128## ##STR00129## ##STR00130## wherein R.sub.N1 and R.sub.N2 each independently represents C.sub.1-12 linear or branched alkyl or alkoxy, or C.sub.2-12 linear or branched alkenyl or alkenoxy, one or more nonadjacent —CH.sub.2— in the C.sub.1-2 linear or branched alkyl or alkoxy, or the C.sub.2-12 linear or branched alkenyl or alkenoxy can each be independently replaced by —C≡C—, —O—, —CO—, —CO—O— or —O—CO—.

8. The liquid crystal composition according to claim 1, wherein the compound of general Formula N is 0.1%-50% by weight of the total weight of the liquid crystal composition.

9. The liquid crystal composition according to claim 1, wherein the compound of general Formula M is selected form a group consisting of the following compounds: ##STR00131## ##STR00132## ##STR00133## wherein R.sub.M1 and R.sub.M2 each independently represents —H, —F, ##STR00134## C.sub.1-12 linear or branched halogenated or unhalogenated alkyl or alkoxy, or C.sub.2-12 linear or branched halogenated or unhalogenated alkenyl or alkenoxy, one or more nonadjacent —CH.sub.2— in the C.sub.1-12 linear or branched halogenated or unhalogenated alkyl or alkoxy, or the C.sub.2-12 linear or branched halogenated or unhalogenated alkenyl or alkenoxy can each be independently replaced by —C≡C—, —O—, —CO—, —CO—O— or —O—CO—.

10. The liquid crystal composition according to claim 9, wherein the compound of general Formula M is 1%-80% by weight of the total weight of the liquid crystal composition.

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

Description

DETAILED EMBODIMENTS

(1) 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.

(2) 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:

(3) TABLE-US-00001 TABLE 1 Codes of the group structures of the liquid crystal compounds Unit structure of group Code Name of the group C 1,4-cyclohexylidene A 1-oxane-2,5-diyl 0 D 1,3-dioxane-2,5-diyl P 1,4-phenylene G 2-fluoro-1,4-phenylene U 2,5-difluoro-1,4-phenylene W 2,3-difluoro-1,4-phenylene —CH.sub.2CH.sub.2— 2 ethyl bridge bond V(2F) difluorovinyl —OCF.sub.3 OCF3 trifluoromethoxy —F F fluoro substituent —O— O oxygen substituent —CF.sub.2O— 1(2F)O or Q difluoromethoxy —CH.sub.2O— 1O methyleneoxy —COO— E ester bridge bond —C.sub.nH.sub.2n+1 n(n represents alkyl a positive integer of 1-12) —CH═CH— or V ethenyl —CH═CH.sub.2

(4) Take the compound with the following structural formula as an example:

(5) ##STR00096##

(6) Represented by the codes listed in Table 1, this structural formula can be expressed as nCCGF, 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”, G represent 2-fluoro-1,4-phenylene, F represents fluorine.

(7) The abbreviated codes of the test items in the following Examples are represented as follows:

(8) TABLE-US-00002 Cp clearing point (nematic-isotropy phases transition temperature, °C.) Δn optical anisotropy (589 nm, 25 °C.) Δε dielectric anisotropy (1 KHz, 25 °C.) K.sub.11 splay elastic constant (pN at 25 °C.) K.sub.22 twist elastic constant (pN at 25 °C.) K.sub.33 bend elastic constant (pN at 25 °C.) K.sub.ave average elastic constant (the average value of K.sub.11, K.sub.22 and K.sub.33) T Transmittance (DMS 505 tester, cell gap 3.5 μm) in which,

(9) the optical anisotropy is measured with an Abbe refractometer under sodium lamp (589 nm) light source at 25° C.

(10) Δε=ε.sub.I−ε.sub.⊥±, in which, ε.sub.I is the dielectric constant parallel to the molecular axis, ε.sub.⊥ is the dielectric constant perpendicular to the molecular axis, with the test conditions: 25° C., 1 KHz, TN90 type test cell with a cell gap of 7 μm.

(11) K.sub.11, K.sub.22 and K.sub.33 are calculated from the measured C-V curve of the liquid crystal using LCR meter and an antiparallel rubbed cell, with the following test conditions: a cell gap of 7 μm, V=0.1˜20 V. K.sub.ave=(K.sub.11+K.sub.22+K.sub.33)/3.

(12) Test condition of transmittance (T). The transmittance of the optic-tunable device is measured at the temperature of clearing point ±10° C. using DMS 505 tester. The optic-tunable device is a IPS mode liquid crystal testing cell with a cell gap of 3.5 μm.

(13) The components used in the following Examples can either be synthesized by method known in the art or be obtained commercially. The synthetic techniques are conventional, and each of the obtained liquid crystal compounds is tested to meet the standards of electronic compound.

(14) The liquid crystal compositions are prepared in accordance with the ratios specified in the following Examples through conventional methods in the art, such as heating, ultrasonic wave, or suspension.

(15) The liquid crystal compositions of following Examples are prepared and then tested. The components and test results for the performances of the liquid crystal composition of each Example are shown below.

Comparative Example 1

(16) 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.

(17) TABLE-US-00003 TABLE 2 Formulation of the liquid crystal composition and its test performances Test results for the Code of Weight performance component percentage parameters 3CCPOCF3 9 Δn 0.095 1PP2V 8.5 Cp 87.5 VCVCP1 4 K.sub.ave 11 3CCV 41 Δε 3.1 3CCV1 5 T 12.45% 3PGP2V(2F) 2.5 3CPUF 3 4CCPUF 3 3CCPUF 6 2PGUQPOCF3 5 3PGUQPOCF3 5 3CC1OWO2 4 4CC1OWO2 4 Total 100

Example 1

(18) 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.

(19) TABLE-US-00004 TABLE 3 Formulation of the liquid crystal composition and its test performances Test results for the Code of Weight performance component percentage parameters 3CCPOCF3 7 Δn 0.101 1PP2V 8 Cp 90.5 VCCP1 8 K.sub.ave 12.8 3CCV 35 Δε 4.3 3CCV1 12 T 14.26% 3CDPUF 3 3CD2PUF 5 2PGUQPOCF3 3 3PGUQPOCF3 3 4PGUQPOCF3 3 3CPWO2 5 4CPWO2 5 3CCWWO2 3 Total 100

Example 2

(20) 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.

(21) TABLE-US-00005 TABLE 4 Formulation of the liquid crystal composition and its test performances Test results for the Code of Weight performance component percentage parameters 3CCPOCF3 7.5 Δn 0.098 VCCP1 4 Cp 92.3 3CCV 41 K.sub.ave 13 V2CCP1 4 Δε 4.6 3CCV1 9 T 14.87% 3PGP2V(2F) 2.5 3D2PUF 3 3CDPUF 6 3CD2PUF 6 2APUQUF 2 3APUQUF 5 3CCWWO2 5 4CCWWO2 5 Total 100

Example 3

(22) 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.

(23) TABLE-US-00006 TABLE 5 Formulation of the liquid crystal composition and its test performances Test results for the Code of Weight performance component percentage parameters 3CCPOCF3 3 Δn 0.1 1PP2V 4.5 Cp 90.9 VCVCP1 4 K.sub.ave 13.5 3CCV 41 Δε 4.7 V2CCP1 4 T 15.12% 3CCV1 9 3PGP2V(2F) 2.5 3D2PUF 3 3CDPUF 3 3CD2PUF 6 2CDUQUF 5 3APUQUF 5 3CC1OWO2 5 4CC1OWO2 5 Total 100

Example 4

(24) 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.

(25) TABLE-US-00007 TABLE 6 Formulationof the liquid crystal composition and its test performances Test results for the Code of Weight performance component percentage parameters 3CCPOCF3 3 Δn 0.105 1PP2V 4.5 Cp 93.9 3CC1OC2 4 K.sub.ave 13.8 3CCV 41 Δε 6.2 V2CCP1 4 T 14.95% 3CCV1 9 3PGPF 2.5 3DC1OPGF 5 3CDPUF 5 3CD2PUF 6 2CDUQUF 5 3APUQUF 6 3CPWO2 5 Total 100

Example 5

(26) 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.

(27) TABLE-US-00008 TABLE 7 Formulation of the liquid crystal composition and the its performances Test results for the Code of Weight performance component percentage parameters 1PP2V 4.5 Δn 0.113 VCCP1 4 Cp 92.1 3CCV 41 K.sub.ave 13.2 V2CCP1 4 Δε 5.1 3CCV1 9 T 14.75% 3PGPF 2.5 3DC1OPGF 3 3CDPUF 3 3CD2PUF 6 2CDUQUF 5 3APUQUF 5 3CDUQUF 3 3CPWO2 5 4CPWO2 5 Total 100

Example 6

(28) 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.

(29) TABLE-US-00009 TABLE 8 Formulation of the liquid crystal composition and its test performances Test results for the Code of Weight performance component percentage parameters 1PP2V 5 Δn 0.108 VCCP1 4 Cp 90.8 3CCV 43.5 K.sub.ave 13.5 V2CCP1 4 Δε 4.8 3CCV1 9 T 15.32% 3DC1OPGF 3 3CDPUF 3 3CD2PUF 6 2CDUQUF 5 3APUQUF 5 3PPWO2 5 4PPWO2 5 3CCWO2 2.5 Total 100

(30) Based on the above Comparative Example 1 and Examples 1-6, it is indicated that the liquid crystal composition provided herein has a higher optical anisotropy, a higher clearing point, a higher dielectric anisotropy, a high transmittance and a larger average elastic constant. When applied in the IPS liquid crystal display devices, it can effectively increase the transmittance of the display devices and impart the display devices with good display performance and energy-saving and environment-friendly characteristics.

(31) The above embodiments are merely illustrative of the technical concepts and the features of the present invention, are included merely for purposes of illustration and implement of the present invention, and are not intended to limit the scope of the present invention. Equivalent variations or modifications are intended to be included within the scope of the invention.