Liquid crystal composition, liquid crystal display element and liquid crystal display

Abstract

Disclosed are a liquid crystal composition, a liquid crystal display element, and a liquid crystal display, said liquid crystal composition comprising one or more compounds represented by formula I, one or more compounds represented by formula II, one or more compounds represented by formula III and one or more compounds represented by formula IV, ##STR00001##
The liquid crystal composition of the present invention has a good stability to light and heat and a lower viscosity, and can attain a wider refractive index and a high clearing point (a wide service temperature range), and in particular, the liquid crystal composition has a high light transmittance, thus allowing a display device to have a high brightness or an energy saving effect.

Claims

1. A liquid crystal composition, wherein said liquid crystal composition comprises one or more compounds represented by formula I, one or more compounds represented by formula II, one or more compounds represented by formula III and one or more compounds represented by formula IV2 and IV11, ##STR00040## ##STR00041## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.5, and R.sub.6 each independently represent an alkyl group having a carbon atom number of 1-10, an alkoxy group having a carbon atom number of 1-10, an alkenyl group having a carbon atom number of 2-10, or an alkenoxy group having a carbon atom number of 3-8, and any one or more non-connected CH.sub.2 in the groups represented by R.sub.1 and R.sub.3 are substituted with cyclopentyl, cyclobutyl, cyclopropyl or —O—; R.sub.4 represents F, CF.sub.3, OCF.sub.3, OCHF.sub.2 or OCH.sub.2F; ##STR00042## each independently represent ##STR00043## or any fluorobenzene; ##STR00044## each independently represent benzene or any fluorobenzene; ##STR00045## represents ##STR00046## or any fluorobenzene; m, p and w each independently represent 1, 2 or 3; n and q each independently represent 0 or 1; and R.sub.71 represents an alkyl group having a carbon atom number of 1-6 or an alkenyl group having a carbon atom number of 2-6.

2. The liquid crystal composition according to claim 1, wherein said one or more compounds represented by formula I are selected from the groups consisting of compounds represented by formulas I1 to I14; said one or more compounds represented by formula II are selected from the group consisting of compounds represented by formulas II1 to II14; said one or more compounds represented by formula III are selected from the group consisting of compounds of formulas III1 to III5; ##STR00047## ##STR00048## ##STR00049## wherein R.sub.11 and R.sub.31 each independently represent an alkyl group having a carbon atom number of 1-6; (O)R.sub.21 represents an alkyl or alkoxyl having a carbon atom number of 1-5; R.sub.51 and R.sub.61 each independently represent an alkyl group having a carbon atom number of 1-6, an alkoxy group having a carbon atom number of 1-6, an alkenyl group having a carbon atom number of 2-6 or an alkenyloxy group having a carbon atom number of 3-6.

3. The liquid crystal composition according to claim 1, wherein in said liquid crystal composition, the total content in mass percentage of said one or more compounds represented by formula I is 1-40%, the total content in mass percentage of said one or more compounds represented by formula II is 1-40%, the total content in mass percentage of said one or more compounds represented by formula III is 1-80%, and the total content in mass percentage of said one or more compounds represented by formula IV is 0.5-30%.

4. The liquid crystal composition according to claim 1, wherein said liquid crystal composition further comprises one or more compounds represented by formula V, ##STR00050## wherein R.sub.9 represents an alkyl group having a carbon atom number of 1-10, a fluoro-substituted alkyl group having a carbon atom number of 1-10, an alkoxy group having a carbon atom number of 1-10, a fluoro-substituted alkoxy group having a carbon atom number of 1-10, an alkenyl group having a carbon atom number of 2-10, a fluoro-substituted alkenyl group having a carbon atom number of 2-10, an alkenoxy group having a carbon atom number of 3-8 or an fluoro-substituted alkenoxy group having a carbon atom number of 3-8, and any one or more CH.sub.2 in the group represented by R.sub.9 are optionally substituted with cyclopentyl, cyclobutyl or cyclopropyl; ##STR00051## each independently represent ##STR00052## r represents 0, 1, 2 or 3; Z.sub.1 and Z.sub.2 each independently represent a single bond, —CF.sub.2O—, —CH.sub.2CH.sub.2—or —CH.sub.2O—; and Y.sub.2 represents F, a fluoro-substituted alkyl group having a carbon atom number of 1-5, a fluoro-substituted alkoxy group having a carbon atom number of 1-5, a fluoro-substituted alkenyl group having a carbon atom number of 2-5, or a fluoro-substituted alkenoxy group having a carbon atom number of 3-8.

5. The liquid crystal composition according to claim 4, wherein said one or more compounds represented by formula V are selected from the groups consisting of compounds represented by formulas V0 to V25, ##STR00053## ##STR00054## ##STR00055## ##STR00056## wherein R.sub.9 represents an alkyl group having a carbon atom number of 1-10, a fluoro-substituted alkyl group having a carbon atom number of 1-10, an alkoxy group having a carbon atom number of 1-10, a fluoro-substituted alkoxy group having a carbon atom number of 1-10, an alkenyl group having a carbon atom number of 2-10, a fluoro-substituted alkenyl group having a carbon atom number of 2-10, an alkenoxy group having a carbon atom number of 3-8 or a fluoro-substituted alkenoxy group having a carbon atom number of 3-8, and any one or more CH.sub.2 in the group represented R.sub.9 are substituted with cyclopentyl, cyclobutyl or cyclopropyl; (F) each independently represents H or F; and in formula V23, X.sub.1 and X.sub.2 each independently represent H or F, Y.sub.2 represents F, a fluoro-substituted alkyl group having a carbon atom number of 1-5, a fluoro-substituted alkoxy group having a carbon atom number of 1-5, a fluoro-substituted alkenyl group having a carbon atom number of 2-5 or a fluoro-substituted alkenoxy group having a carbon atom number of 3-8.

6. The liquid crystal composition according to claim 1, wherein said liquid crystal composition further comprises one or more compounds represented by formula VI, ##STR00057## wherein R.sub.10 and R.sub.12 each independently represent an alkyl group having a carbon atom number of 1-10, fluoro, a fluoro-substituted alkyl group having a carbon atom number of 1-10, an alkoxy group having a carbon atom number of 1-10, a fluoro-substituted alkoxy group having a carbon atom number of 1-10, an alkenyl group having a carbon atom number of 2-10, a fluoro-substituted alkenyl group having a carbon atom number of 2-10, an alkenoxy group having a carbon atom number of 3-8 or a fluoro-substituted alkenoxy group having a carbon atom number of 3-8, and any one or more CH.sub.2 in the groups represented by R.sub.10 and R.sub.12 are optionally substituted with cyclopentyl, cyclobutyl or cyclopropyl; Z.sub.3 and Z.sub.4 each independently represent a single bond, —CH.sub.2CH.sub.2— or —CH.sub.2O—; ##STR00058## each independently represent ##STR00059## a represents 1, 2 or 3; b represents 0 or 1.

7. The liquid crystal composition according to claim 6, wherein said one or more compounds represented by formula VI are selected from the groups consisting of compounds represented by formulas VI1 to VI12, ##STR00060## ##STR00061## wherein R.sub.10 and R.sub.12 each independently represent an alkyl group having a carbon atom number of 1-10, fluoro, a fluoro-substituted alkyl group having a carbon atom number of 1-10, an alkoxy group having a carbon atom number of 1-10, a fluoro-substituted alkoxy group having a carbon atom number of 1-10, an alkenyl group having a carbon atom number of 2-10, a fluoro-substituted alkenyl group having a carbon atom number of 2-10, an alkenoxy group having a carbon atom number of 3-8 or a fluoro-substituted alkenoxy group having a carbon atom number of 3-8, and any one or more CH.sub.2 in the groups represented by R.sub.10 and R.sub.12 are optionally substituted with cyclopentyl, cyclobutyl or cyclopropyl.

8. The liquid crystal composition according to claim 1, wherein said liquid crystal composition further comprises one or more compounds represented by formula VII, ##STR00062## wherein R.sub.13 and R.sub.14 each independently represent an alkyl group having a carbon atom number of 1-10, a fluoro-substituted alkyl group having a carbon atom number of 1-10, an alkoxy group having a carbon atom number of 1-10, a fluoro-substituted alkoxy group having a carbon atom number of 1-10, an alkenyl group having a carbon atom number of 2-10, a fluoro-substituted alkenyl group having a carbon atom number of 2-10, an alkenoxy group having a carbon atom number of 3-8 or a fluoro-substituted alkenoxy group having a carbon atom number of 3-8, and any one or more CH.sub.2 in the groups represented by R.sub.13 and R.sub.14 are optionally substituted with cyclopentyl, cyclobutyl or cyclopropyl; and W represents —O—, —S— or —CH.sub.2O—.

9. The liquid crystal composition according to claim 1, further comprising one or more compounds represented by formula VIII, ##STR00063## wherein R.sub.14 represents an alkyl group having a carbon atom number of 1-5 or an alkenyl group having a carbon atom number of 2-5; R.sub.15 represents an F atom, an alkyl group having a carbon atom number of 1-5, an alkoxy group having a carbon atom number of 1-5 or an alkenyl group having a carbon atom number of 2-5, and any one or more CH.sub.2 in the groups represented by R.sub.15 and R.sub.16 are optionally substituted with cyclopentyl, cyclobutyl or cyclopropyl; s represents 0 or 1; and (F) represents H or F.

10. A liquid crystal display element or liquid crystal display comprising the liquid crystal composition of claim 1, wherein said liquid crystal display element or liquid crystal display is an active matrix display element or display or a passive matrix display element or display.

Description

DETAILED DESCRIPTION OF EMBODIMENTS

(1) The present invention is further described in conjunction with particular examples below, but the present invention is not limited to the following examples. Methods for the synthesis of compounds in liquid crystal compositions are all conventional methods, unless otherwise specified. Raw materials for the synthesis of the liquid crystal compositions are all commercially available, unless otherwise specified.

(2) In the reaction process, the reaction progress is generally monitored by means of TLC, and treatments after the completion of the reaction are generally water washing, extraction, organic phase combination and drying, solvent evaporation under reduced pressure, as well as recrystallization and column chromatography; and a person skilled in the art would be able to implement the present invention according to the following description.

(3) In the present specification, the percentages are mass percentages, the temperatures are in degree Celsius (° C.), and the specific meanings of other symbols and the test conditions are as follows:

(4) Cp represents a clearing point (° C.) of the liquid crystal measured by a DSC quantitative method;

(5) Δn represents an optical anisotropy, n.sub.o is the refractive index of an ordinary light, n.sub.e is the refractive index of an extraordinary light, the test conditions are 25±2° C., 589 nm and an Abbe refractometer is used for the test;

(6) Δε represents a dielectric anisotropy, Δε=ε.sub.//−ε.sub.⊥, wherein ε.sub.// is a dielectric constant parallel to a molecular axis, and ε.sub.⊥ is a dielectric constant perpendicular to the molecular axis, the test conditions are 25±0.5° C., and a 20 micron parallel cell is used and an INSTEC: ALCT-IR1 is used for the test;

(7) γ1 represents a rotary viscosity (mPa.Math.s), the test conditions are 25±0.5° C., and a 20 micron parallel cell is used and an INSTEC: ALCT-IR1 is used for the test; and

(8) Tr (%) represents a transmittance, Tr (%)=100%*bright state (Vop) luminance/light source luminance, the test equipment is DMS501, and the test conditions are 25±0.5° C., the test cell is a 3.3 micron IPS test cell, both the electrode spacing and the electrode width both are 10 microns, and an included angle between the frictional direction and the electrode of 10°; since ε.sub.⊥ and Tr have a positive correlation, when evaluating the transmittance, ε.sub.⊥ can be used as an evaluation index for indication.

(9) In the examples of the present invention application, liquid crystal monomer structures are represented by codes, wherein the code representation of ring structures, end groups and linking groups of the liquid crystals are shown in tables (I) and (II) below.

(10) TABLE-US-00001 TABLE (I) Corresponding code for ring structure Ring structure Corresponding code C P G U GI Y 0 A D L BHHO-m-nFF B B(S)

(11) TABLE-US-00002 TABLE (II) Corresponding code for end group and linking group End group and linking group Corresponding code C.sub.nH.sub.2n+1— n- C.sub.nH.sub.2n+1O— nO- —OCF.sub.3 OT —CF.sub.3 -T —CF.sub.2O— Q —F —F —CN —N —CH.sub.2CH.sub.2— E —CH═CH— V —C≡C— T —COO— Z —CH═CH—C.sub.nH.sub.2n+1 -Vn C(5) C(4) C(3)1

EXAMPLES

(12) ##STR00039##

Example 1

(13) TABLE-US-00003 Category Liquid crystal monomer code Content (%) VI CY-3-O2 2 VI CCY-3-O2 3 VI PY-5-O2 2 VI CPY-3-O2 3 V CCU-3-F 5 V CGU-5-F 3 V PGUQU-3-F 2 III CC-3-V 20 II PUQY-3-F 10 II PUQY-5-F 10 II PGUQY-3-F 10 I PUQY-3-O2 10 I PUQY-3-O4 10 I PGUQY-3-O2 10 Δε[1 KHz, 20° C.]: 4.7 ε.sub.⊥: 6.3 Δn[589 nm, 20° C.]: 0.133 Cp: 105° C. γ.sub.1: 68 mPa .Math. s. Tr: 6.5%

Example 2

(14) TABLE-US-00004 Category Liquid crystal monomer code Content (%) IV CPY-3-F 3 IV CCY-5-F 5 IV CGY-3-F 5 IV PPY-3-F 2 III CC-3-V 20 III CCP-3-O1 5 III CPP-1-5 5 II PUQY-3-F 5 II PGUQY-5-F 5 II PUQY-5-F 5 I PUQY-C(3)1-O2 8 I PGUQY- C(3)1-O2 8 I PUQY-3-O2 8.5 I PGUQY-3-O2 8 I APUQY-3-O2 7.5 Δε[1 KHz, 20° C.]: 4.6 ε.sub.⊥: 6.8 Δn[589 nm, 20° C.]: 0.101 Cp: 80° C. γ.sub.1: 99 mPa .Math. s. Tr: 7.3%

(15) The liquid crystal compositions are poured into test cells for testing, resulting in: the transmittance of Example 1 being 6.5% and the transmittance of Example 2 being 7.3%, which is increased by 12% higher than that of Example 1.

Example 3

(16) TABLE-US-00005 Category Liquid crystal monomer code Content (%) IV CPY-5-F 2 IV CDY-4-F 1 IV CGY-5-OT 2 IV CPY-2-OT 2 III CC-3-V 44 III CC-2-3 4 III CCP-3-1 4 II PUQY-3-F 10 II PGUQY-5-F 10 II PUQY-5-F 10 II PGUQY-4-F 10 I PGUQY-3-O2 1 Δε[1 KHz, 20° C.]: 2.4 ε.sub.⊥: 4.9 Δn[589 nm, 20° C.]: 0.101 Cp: 77° C. γ.sub.1: 77 mPa .Math. s. Tr: 7.1%

Example 4

(17) TABLE-US-00006 Category Liquid crystal monomer code Content (%) IV CPY-C(5)-F 6 IV CLY-4-F 6 IV PGY-C(3)-OT 6 IV CCPY-2-F 6 IV CCGY-3-F 6 III CC-3-V 35 III CC-3-5 5 III CCP-V-OT 8 II DGUQY-3-F 1 I PUQY-3-02 6 I APUQY-3-02 5 I CPUQY-3-02 5 I PGUQY-3-02 5 Δε[1 KHz, 20° C.]: 2.5 ε.sub.⊥: 4.8 Δn[589 nm, 20° C.]: 0.101 Cp: 82° C. γ.sub.1: 80 mPa .Math. s. Tr: 7.1%

Example 5

(18) TABLE-US-00007 Category Liquid crystal monomer code Content (%) V PUQU-3-F 5 IV CPY-C(3)-F 1 III CC-3-V 50 III CCP-V-1 8 III CCP-V2-1 8 III CP-3-O2 3 III CCG-V-F 7 III CGPC-3-3 4 II DGUQY-3-F 3 II PGUQY-5-F 2 I PUQY-3-O2 3 I PGUQY-3-O2 3 I PGUQY-C(3)1-O2 3 Δε[1 KHz, 20° C.]: 4.0 ε.sub.⊥: 7.0 Δn[589 nm, 20° C.]: 0.105 Cp: 77° C. γ.sub.1: 60 mPa .Math. s. Tr: 7.4%

Example 6

(19) TABLE-US-00008 Category Liquid crystal monomer code Content (%) V CCU-3-F 5 V CPU-3-F 5 V CCP-3-OT 5 V PGUQU-C(5)-F 5 IV CPY-2-F 3 IV CPPY-4-F 3 III CC-3-V 30 III CCP-3-V1 2 III CP-3-O2 3 II DGUQY-3-F 9 II PGUQY-5-F 9 II PUQY-3-F 9 II CUQY-3-F 5 I PUQY-3-O2 3 I PUQY-5-O2 3 Δε[1 KHz, 20° C.]: 3.7 ε.sub.⊥: 6.8 Δn[589 nm, 20° C.]: 0.107 Cp: 78° C. γ.sub.1: 77 mPa .Math. s. Tr: 7.0%

Example 7

(20) TABLE-US-00009 Category Liquid crystal monomer code Content (%) V CGU-5-F 5 V APUQU-C(5)-F 5 V PUQU-C(3)1-F 5 V PGUQU-C(3)1-F 5 V PGUQU-3-F 5 V PPGI-3-F 5 IV CPY-2-F 3 IV CPGY-4-F 3 III CC-3-V 19 III CPP-3-2 5 II PUQY-3-F 5 I PUQY-3-O2 10 I PUQY-3-O4 10 I PGUQY-3-O2 10 I PGUQY-4-O2 5 Δε[1 KHz, 20° C.]: 4.5 ε.sub.⊥: 7.1 Δn[589 nm, 20° C.]: 0.115 Cp: 85° C. γ.sub.1: 86 mPa .Math. s. Tr: 7.3%

Example 8

(21) TABLE-US-00010 Category Liquid crystal monomer code Content (%) V CCU-5-F 7 V PGU-3-F 6 V CPUQU-C(5)-F 8 V PUQU(2M)-3-F 6 V PGUQU(2M)-3-F 6 V PUQU-C(5)-F 7 IV CPY-2-F 3 IV CPGY-4-F 3 III CC-3-V 15 III CCG-V-F 5 II PUQY-3-F 4 I PUQY-3-O2 8 I PUQY-3-O4 8 I PGUQY-3-O2 9 I PGUQY-4-O2 5 Δε[1 KHz, 20° C.]: 5.8 ε.sub.⊥: 8.7 Δn[589nm, 20° C.]: 0.125 Cp: 88° C. γ.sub.1: 80 mPa .Math. s. Tr: 7.3%

Example 9

(22) TABLE-US-00011 Category Liquid crystal monomer code Content (%) VI CY-3-O2 2 VI CCY-3-O2 3 VI PY-5-O2 2 VI CPY-3-O2 3 V CCU-3-F 4 V CGU-5-F 3 V PGUQU-3-F 3 IV CPY-3-OT 3 IV PPY-3-OT 2 III CC-3-V 19 II PUQY-3-F 9 II PUQY-5-F 9 II PGUQY-3-F 10 I PUQY-3-O2 9 I PUQY-3-O4 9 I PGUQY-3-O2 10 Δε[1 KHz, 20° C.]: 3.3 ε.sub.⊥: 5.3 Δn[589 nm, 20° C.]: 0.134 Cp: 80° C. γ.sub.1: 82 mPa .Math. s. Tr: 7.1%

Example 10

(23) TABLE-US-00012 Category Liquid crystal monomer code Content (%) VI CPY-3-O2 7 VI PYP-3-O2 8 VI COY-3-O2 7 VI CCOY-3-O2 8 V CCU-3-F 6 V CGU-5-F 5 V PGUQU-3-F 5 IV CPY-3-F 3 III CC-3-V 22 III CCP-V-1 6 III CCG-V-F 5 II PUQY-3-F 6 II PUQY-5-F 3 II PGUQY-3-F 3 I PUQY-3-O2 2 I PUQY-3-O4 2 I PGUQY-3-O2 2 Δε[1 KHz, 20° C.]: 3.1 ε.sub.⊥: 5.0 Δn[589 nm, 20° C.]: 0.101 Cp: 78° C. γ.sub.1: 70 mPa .Math. s. Tr: 7.1%

Example 11

(24) TABLE-US-00013 Category Liquid crystal monomer code Content (%) VII B-3-O2 2 VII B(S)-3-O4 2 VII BHHO-3-2FF 1 VI CPY-3-O2 7 VI COY-3-O2 7 VI CCOY-3-O2 6 V CCU-3-F 5 V CGU-5-F 5 V PGUQU-3-F 5 V DCU-3-F 5 V CDU-3-F 5 V CCGU-3-F 5 IV CCY-4-F 2 III CC-3-V 30 II PUQY-3-F 1 II PUQY-5-F 1 II PGUQY-3-F 1 I PUQY-3-O2 3 I PUQY-3-O4 3 I PGUQY-3-O2 4 Δε[1 KHz, 20° C.]: 4.7 ε.sub.⊥: 7.0 Δn[589 nm, 20° C.]: 0.107 Cp: 79° C. γ.sub.1: 75 mPa .Math. s. Tr: 7.2%

Example 12

(25) TABLE-US-00014 Category Liquid crystal monomer code Content (%) VIII PGP-3-2 2 VIII PGP-3-F 3 VIII PP-1-5 1 VIII PGP-V-F 2 VII B-3-O2 2 VI CPY-3-O2 3 V CCU-3-F 5 V CGU-5-F 5 V PGUQU-3-F 5 V DCU-3-F 5 V CDU-3-F 5 IV CLY-4-F 2 III CC-2-3 2 III CC-3-V 40 III CC-3-V1 2 III CCP-V-1 1 II PUQY-3-F 2 II PUQY-5-F 2 II PGUQY-3-F 3 I PUQY-3-O2 3 I PUQY-3-O4 3 I PGUQY-3-O2 2 Δε[1 KHz, 20° C.]: 4.3 ε.sub.⊥: 6.7 Δn[589 nm, 20° C.]: 0.104 Cp: 75° C. γ.sub.1: 53 mPa .Math. s. Tr: 7.2%

(26) By using the combination of compounds of formulas I, II and IV in the examples of the present invention, the dielectric anisotropy in the vertical direction of the liquid crystal compositions can be significantly increased without reducing the Δε of the liquid crystal compositions, so that the transmittances of the liquid crystal compositions can be greatly improved. The compound represented by formula III has a low rotary viscosity and also a higher clearing point (Cp), and when the compound is used in combination with compounds represented by formulas I, II and V, the rotary viscosity of the liquid crystal composition is reduced and the response speed thereof is accelerated. The liquid crystal composition of the present invention has a good stability to light and heat, a lower viscosity and a faster response speed, and can attain a wider refractive index and a higher clearing point (a wide service temperature range), and in particular, the liquid crystal composition has a higher light transmittance, thus allowing a display device to have a higher brightness or an energy saving effect.