LIQUID CRYSTAL COMPOSITION AND DISPLAY DEVICE THEREOF
20170233651 · 2017-08-17
Assignee
Inventors
Cpc classification
C09K19/20
CHEMISTRY; METALLURGY
International classification
Abstract
The present invention discloses a liquid crystal composition, comprising: at least a first compound selected from the group consisting of a compound of general Formula I-1, a compound of general Formula I-2, and a combination thereof, and at least a second compound selected from the group consisting of a compound of general Formula II-1, a compound of general Formula II-2, a compound of general Formula II3, a compound of general Formula II-4 and a combination thereof The liquid crystal composition provided in the present invention has the properties of appropriate optical and dielectric anisotropies, high clearing point, existence of a nematic phase over a wide range of temperature, low viscosity and good high-temperature stability. The liquid crystal composition is applicable to a liquid crystal display (LCD) device, to enable the LCD device to have such properties as short response time, excellent display effect at high temperature, and others.
##STR00001##
Claims
1. A liquid crystal composition, comprising: a first compound, which is one or more selected from the group consisting of a compound of general Formula I-1, a compound of general Formula I-2, and a combination thereof: ##STR00022## and a second compound, which is one or more selected from the group consisting of a compound of general Formula II-1, a compound of general Formula II-2, a compound of general Formula II-3, a compound of general Formula II-4, and a combination thereof: ##STR00023## wherein: R.sub.1 and R.sub.2 are the same or different, and each independently denote an alkyl group having 2 to 5 carbon atoms; R.sub.3, R.sub.5, R.sub.6, R.sub.7, R.sub.8, R.sub.9 and R.sub.10 are the same or different, and each independently denote an alkyl or alkoxy group having 1 to 5 carbon atoms, or an alkenyl group having 2 to 5 carbon atoms; R.sub.4 denotes an alkenyl group having 2 to 5 carbon atoms; and L.sub.1 denotes H or F.
2. The liquid crystal composition according to claim 1, wherein the first compound is one or more selected from the compounds of general Formula I-1.
3. The liquid crystal composition according to claim 1, wherein the first compound is one or more selected from the compounds of general Formula I-2.
4. The liquid crystal composition according to claim 1, wherein the second compound comprises one or more selected from the compounds of general Formula II-1.
5. The liquid crystal composition according to claim 1, wherein the liquid crystal composition further comprising: a third compound, which is one or more selected from the group consisting of a compound of general Formula III-1, a compound of general Formula III-2, a compound of general Formula III-3 and a combination thereof: ##STR00024## wherein: R.sub.11, R.sub.12, R.sub.13, R.sub.14, R.sub.15 and R.sub.16 are the same or different, and each independently denote an alkyl group having 1 to 5 carbon atoms, or an alkenyl group having 2 to 5 carbon atoms; L.sub.2 and L.sub.3 are the same or different, and each independently denote H or F.
6. The liquid crystal composition according to claim 5, wherein the third compound accounts for 0-20% of the total weight of the liquid crystal composition.
7. The liquid crystal composition according to claim 1, wherein the first compound accounts for 10-90% of the total weight of the liquid crystal composition, and the second compound accounts for 10-90% of the total weight of the liquid crystal composition.
8. The liquid crystal composition according to claim 5, wherein the first compound accounts for 10-90% of the total weight of the liquid crystal composition; the second compound accounts for 10-90% of the total weight of the liquid crystal composition; and the third compound accounts for 0-15% of the total weight of the liquid crystal composition.
9. The liquid crystal composition according to claim 7, wherein the first compound accounts for 10-45% of the total weight of the liquid crystal composition, and the second compound accounts for 55-90% of the total weight of the liquid crystal composition.
10. The liquid crystal composition according to claim 8, wherein the first compound accounts for 10-45% of the total weight of the liquid crystal composition; the second compound accounts for 55-90% of the total weight of the liquid crystal composition; and the third compound accounts for 0-10% of the total weight of the liquid crystal composition.
11. The liquid crystal composition according to claim 1, wherein the compound of general Formula I-1 is one or more selected from the group consisting of: ##STR00025## and the compound of general Formula I-2 is one or more selected from the group consisting of: ##STR00026##
12. The liquid crystal composition according to claim 1, wherein the compound of general Formula II-1 is one or more selected from the group consisting of: ##STR00027## the compound of general Formula II-2 is one or more selected from the group consisting of: ##STR00028## the compound of general Formula II-3 is one or more selected from the group consisting of: ##STR00029## and the compound of general Formula II-4 is one or more selected from the group consisting of: ##STR00030##
13. The liquid crystal composition according to claim 5, wherein the compound of general Formula III-1 is one or more selected from the group consisting of: ##STR00031## the compound of general Formula III-2 is one or more selected from the group consisting of: ##STR00032## the compound of general Formula III-3 is one or more selected from the group consisting of: ##STR00033##
14. The liquid crystal composition according to claim 9, wherein the first compound accounts for 10-35% of the total weight of the liquid crystal composition.
15-17. (canceled)
18. The liquid crystal composition according to claim 10, wherein the first compound accounts for 10-35% of the total weight of the liquid crystal composition.
19. The liquid crystal composition according to claim 14, wherein the compound of general Formula I-1 accounts for 0-15% of the total weight of the liquid crystal composition; and the compound of general Formula I-2 accounts for 5-20% of the total weight of the liquid crystal composition.
20. The liquid crystal composition according to claim 18, wherein the compound of general Formula I-1 accounts for 0-15% of the total weight of the liquid crystal composition; and the compound of general Formula I-2 accounts for 5-20% of the total weight of the liquid crystal composition.
21. A liquid crystal display (LCD), wherein it comprises the liquid crystal composition according to claim 1.
Description
DETAILED DESCRIPTION OF THE INVENTION
[0053] Hereinafter, the present invention is described with reference to specific embodiments. It should be noted that the examples below are illustrative of the present invention, and provided merely for explaining, instead of limiting the present invention. Other combinations and various improvements may be made within the concept and without departing from the spirit and scope of the present invention.
[0054] For ease of description, in the following examples, the group structures contained in the liquid crystal compound are designated by the codes listed in Table 1:
TABLE-US-00001 TABLE 1 Codes for group structures contained in the liquid crystal compound Unit structure of the group Code Name of the group
[0055] Taking a compound having a structural formula below as an example:
##STR00021##
[0056] if the structural formula is designated by the codes in Table 1, it may be expressed as nCPUF, where n denotes the number of carbon atoms contained in the alkyl group at the left end, for example, when n is “3”, the alkyl group is -C.sub.3H.sub.7; and C denotes cyclohexylene.
[0057] The test items in the following examples are abbreviated as follows: [0058] Cp (° C.): Clearing point (nematic-isotropic phase transition temperature) [0059] Δn: Optical anisotropy (589 nm, 20° C.) [0060] ΔΔε: Dielectric anisotropy (1 KHz, 25° C.) [0061] γ1: Rotary viscosity (mPa*s, at 20° C.) [0062] VHR Voltage holding ratio (%) [0063] (starting): [0064] VHR (150° C.): Voltage holding ratio (%) determined after 1 h degradation at 150° C.
[0065] The refractivity anisotropy is measured using abbe refractometer under sodium lamp (589 nm) light source at 20° C. The dielectric test cell is the type TN90, and the cell gap is 7 μm.
[0066] Δε=ε∥-ε⊥, wherein ell is the dielectric constant parallel to the molecular axis, and ε⊥ is the dielectric constant perpendicular to the molecular axis; the test conditions include 25° C. and 1 KHz; the dielectric test cell is the type TN90, and the cell gap is 7 μm.
[0067] VHR (starting) is tested by TOYO6254 liquid crystal physical property evaluation system, where the test temperature is 60° C., the test voltage is 5V, and the test time is 166.7 ms; and VHR (150° C.) is tested by TOYO6254 liquid crystal physical property evaluation system after 1 h degradation of the liquid crystal at 150° C., where the test temperature is 60° C., the test voltage is 5 V, and the test time is 166.7 ms.
[0068] Each of the components used in the following examples can be synthesized by a known method or is commercially available. These synthesis techniques are conventional and the resulting liquid crystal compounds are tested to conform to the standards for electronic compounds.
[0069] liquid crystal composition is prepared according to a mixing ratio of the liquid crystal compounds defined in the following examples. The liquid crystal composition is prepared by a conventional method in the art, for example, mixing according to the defined ratio by heating, ultrasonicating, and suspending, etc.
COMPARATIVE EXAMPLE 1
[0070] The liquid crystal composition of Comparative Example 1 was prepared with the compounds in percentages by weight shown in Table 2, and then filled between two substrates of an LCD display for performance test. The test data is shown in a table below.
TABLE-US-00002 TABLE 2 Formulation of liquid crystal composition and performances tested Test result Code of Type of of performance component compound Content, % parameters 3CCV II-1-1 37 Cp 75.0 1PP2V1 7 Δn 0.1152 3PUQUF 15 Δε 5.0 3CGUF 3 γ1 59 2PGP3 II-4-1 5 VHR (starting) 98.3% 2PGP4 II-4-2 7 VHR (150° C.) 90.7% VCCP1 II-2-4 18 3CCGUF 8 In total 100
EXAMPLE 1
[0071] The liquid crystal composition of Example 1 was prepared with the compounds in percentages by weight shown in Table 3, and then filled between two substrates of an LCD display for performance test. The test data is shown in a table below.
TABLE-US-00003 TABLE 3 Formulation of liquid crystal composition and performances tested Test result Code of Type of of performance component compound Content, % parameters 3CCV II-1-1 40 Cp 76.2 4CCV II-1-4 10 Δn 0.116 5CCV II-1-6 10 Δε 5.0 3CPP2 II-3-2 4 γ1 51 2PGP3 II-4-1 4 VHR (starting) 98.5% 2PGP4 II-4-2 4 VHR (150° C.) 97.7% 2PGP5 II-4-3 4 3CCP1 II-2-1 4 2PGUQPOCF3 I-2-1 5 3PGUQPOCF3 I-2-2 6 4PGUQPOCF3 I-2-3 6 5PGUQPOCF3 I-2-4 3 In total 100
EXAMPLE 2
[0072] The liquid crystal composition of Example 2 was prepared with the compounds in percentages by weight shown in Table 4, and then filled between two substrates of an LCD display for performance test. The test data is shown in a table below.
TABLE-US-00004 TABLE 4 Formulation of liquid crystal composition and performances tested Test result Code of Type of of performance component compound Content, % parameters 3CCV II-1-1 40 Cp 80.0 4CCV II-1-4 10 Δn 0.119 5CCV II-1-6 11 Δε 5.0 3CPP2 II-3-2 3 γ1 54 2PGP3 II-4-1 5 VHR (starting) 98.5% 2PGP4 II-4-2 4 VHR (150° C.) 98.1% V2PGP2 II-4-7 4 3PGPC2 III-2-2 2 3CPPC3 III-1-2 2 2PGUQPOCF3 I-2-1 5 3PGUQPOCF3 I-2-2 6 4PGUQPOCF3 I-2-3 4 3PGUQPCF3 I-1-1 4 In total 100
EXAMPLE 3
[0073] The liquid crystal composition of Example 3 was prepared with the compounds in percentages by weight shown in Table 5, and then filled between two substrates of an LCD display for performance test. The test data is shown in a table below.
TABLE-US-00005 TABLE 5 Formulation of liquid crystal composition and performances tested Test result Code of Type of of performance component compound Content, % parameters 3CCV II-1-1 40 Cp 81.5 4CCV II-1-4 10 Δn 0.119 5CCV II-1-6 8 Δε 4.9 2PGP3 II-4-1 5 γ1 57 2PGP4 II-4-2 4 VHR (starting) 98.4% 2PGP5 II-4-3 4 VHR (150° C.) 98.1% 3PGPC2 III-2-2 2 VCCP1 II-2-4 7 2PGUQPOCF3 I-2-1 6 3PGUQPOCF3 I-2-2 5 4PGUQPOCF3 I-2-3 4 5PGUQPOCF3 I-2-4 5 In total 100
COMPARATIVE EXAMPLE 2
[0074] The liquid crystal composition of Comparative Example 2 was prepared with the compounds in percentages by weight shown in Table 6, and then filled between two substrates of an LCD display for performance test. The test data is shown in a table below.
TABLE-US-00006 TABLE 6 Formulation of liquid crystal composition and performances tested Test result Code of Type of of performance component compound Content, % parameters 7CPF 6 Cp 92.0 5CC3 6 Δn 0.086 2CCPOCF3 8 Δε 7.3 3CCPOCF3 8 γ1 125 4CCPOCF3 7 VHR (starting) 98.4% 5CCPOCF3 8 VHR (150° C.) 86.9% 2CCUF 12 3CCUF 11 5CCUF 8 3CGUF 5 3CCEGF 7 5CCEGF 5 3CPGF 9 In total 100
EXAMPLE 4
[0075] The liquid crystal composition of Example 4 was prepared with the compounds in percentages by weight shown in Table 7, and then filled between two substrates of an LCD display for performance test. The test data is shown in a table below.
TABLE-US-00007 TABLE 7 Formulation of liquid crystal composition and performances tested Test result Code of Type of of performance component compound Content, % parameters 3CCV II-1-1 25 Cp 101.3 5CCV II-1-6 8 Δn 0.101 VCCP1 II-2-4 12 Δε 7.4 3CCP1 II-2-1 6 γ1 96 V2CCP1 II-2-5 6 VHR (starting) 98.4% 3CPCC2 III-3-1 5 VHR (150° C.) 96.9% 3PGPC2 III-2-2 3 2PGUQPOCF3 I-2-1 5 3PGUQPOCF3 I-2-2 5 4PGUQPOCF3 I-2-3 5 5PGUQPOCF3 I-2-4 5 3PGUQPCF3 I-1-1 5 4PGUQPCF3 I-1-2 5 5PGUQPCF3 I-1-3 5 In total 100
EXAMPLE 5
[0076] The liquid crystal composition of Example 5 was prepared with the compounds in percentages by weight shown in Table 8, and then filled between two substrates of an LCD display for performance test. The test data is shown in a table below.
TABLE-US-00008 TABLE 8 Formulation of liquid crystal composition and performances tested Test result Code of Type of of performance component compound Content, % parameters 3CCV II-1-1 25 Cp 96.4 5CCV II-1-6 9 Δn 0.098 VCCP1 II-2-4 12 Δε 7.2 3CCP1 II-2-1 6 γ1 91 V2CCP1 II-2-5 6 VHR (starting) 98.4% 3CPCC2 III-3-1 5 VHR (150° C.) 96.7% 3PGP2 II-4-5 3 2PGUQPOCF3 I-2-1 5 3PGUQPOCF3 I-2-2 5 4PGUQPOCF3 I-2-3 5 5PGUQPOCF3 I-2-4 5 3PGUQPCF3 I-1-1 5 4PGUQPCF3 I-1-2 5 5PGUQPCF3 I-1-3 4 In total 100
EXAMPLE 6
[0077] The liquid crystal composition of Example 6 was prepared with the compounds in percentages by weight shown in Table 9, and then filled between two substrates of an LCD display for performance test. The test data is shown in a table below.
TABLE-US-00009 TABLE 9 Formulation of liquid crystal composition and performances tested Test result Code of Type of of performance component compound Content, % parameters 3CCV II-1-1 25 Cp 92.4 5CCV II-1-6 12 Δn 0.09 VCCP1 II-2-4 14 Δε 7.3 3CCP1 II-2-1 6 γ1 88 V2CCP1 II-2-5 6 VHR (starting) 98.5% VCPP3 II-3-3 3 VHR (150° C.) 96.9% 2PGUQPOCF3 I-2-1 6 3PGUQPOCF3 I-2-2 5 4PGUQPOCF3 I-2-3 5 5PGUQPOCF3 I-2-4 4 3PGUQPCF3 I-1-1 6 4PGUQPCF3 I-1-2 5 5PGUQPCF3 I-1-3 3 In total 100
[0078] As can be known from the data obtained in the examples above, the liquid crystal composition provided in the present invention has appropriate optical and dielectric anisotropies, existence of a nematic phase over a wide range of temperature, high clearing point, fast response speed and good high-temperature stability, and is applicable to an LCD display. Compared with Comparative Examples 1 and 2, when the optical anisotropy, the dielectric anisotropy and the clearing point are similar, the liquid crystal composition provided in the present invention has a further shorter response time and better high-temperature stability, and can meet the requirement of fast response speed and excellent display effect at high temperature for an LCD display. Therefore, significant technological advancements are achieved.