LIQUID CRYSTAL DISPLAY DEVICE

Abstract

Disclosed is a liquid crystal display device comprising an array substrate and an opposite substrate arranged facing the array substrate, wherein the structure of said array substrate comprises elongated and evenly spaced slit electrodes and electrode gaps between the slit electrodes, and said opposite substrate comprises a bulk electrode; and further comprises a liquid crystal composition between said array substrate and the opposite substrate. The liquid crystal display device has a higher light transmittance, such that more backlight passes through the liquid crystal display device, resulting in the liquid crystal display device having a higher luminance.

Claims

1. A liquid crystal display device comprising an array substrate and an opposite substrate arranged facing the array substrate, characterized in that the structure of said array substrate comprises elongated and equidistant arrayed slit electrodes and electrode gaps between the slit electrodes, and said opposite substrate comprises a bulk electrode; and further comprises a liquid crystal composition between said array substrate and the opposite substrate.

2. The liquid crystal display device according to claim 1, characterized in that the ratio of the width of said slit electrode to the width of said electrode gap is 1:0.5 to 1:9.

3. The liquid crystal display device according to claim 1, characterized in that the ratio of the width of said slit electrode to the width of said electrode gap is 1:0.5 to 1:2.

4. The liquid crystal display device according to claim 1, characterized in that said liquid crystal composition comprises one or more compounds represented by formula I, and one or more compounds represented by formula II: ##STR00039## wherein A represents a group having a dielectric constant of greater than 0, and B represents a group having a dielectric constant of less than 0; R.sub.0 represents one or more of CF.sub.2O, OCF.sub.2, OCF.sub.2O, CHFO, OCHF, OCHFO, CF.sub.2, CHF, CH.sub.2, CH.sub.2CH.sub.2, CHFCH.sub.2, CH.sub.2CHF, CHFCHF, CF.sub.2CH.sub.2, CH.sub.2CF.sub.2, CF.sub.2CHF, CHFCF.sub.2, CF.sub.2CF.sub.2, CHCH, CFCH, CHCF, CFCF, Si, N, O, S, CR*.sub.2CR**.sub.2, CR*FCR**.sub.2, CR*.sub.2CR**F, CR*FCR**F, CF.sub.2CR**.sub.2, CR*.sub.2CF.sub.2, CF.sub.2CR**F, CR*FCF.sub.2, CR*CR**, CFCR**, CR*CF, ##STR00040## and/or any fluorobenzene; R* and R** each independently represent H, 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; R.sub.1 and R.sub.2 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.1 and R.sub.2 may be substituted with cyclopentyl, cyclobutyl or cyclopropyl; Z.sub.1 and Z.sub.2 each independently represent a single bond, CH.sub.2CH.sub.2 or CH.sub.2O; ##STR00041## and each independently represent one or more of ##STR00042## m represents 1, 2 or 3; and n represents 0 or 1.

5. The liquid crystal display device according to claim 4, characterized in that said one or more compounds represented by formula I are selected from one or more of compounds represented by formulae I1 to 13 below, and said one or more compounds represented by formula II are selected from one or more of compounds represented by formulae II1 to II13 below: ##STR00043## ##STR00044## wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.4 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.1, R.sub.2, R.sub.3 and R.sub.4 may be substituted with cyclopentyl, cyclobutyl or cyclopropyl; ##STR00045## each independently represent one or more of ##STR00046## and any fluorobenzene; each X independently represents CH.sub.2, O or S; p represents 1, 2 or 3; and q represents 0, 1 or 2.

6. The liquid crystal display device according to claim 5, characterized in that said compound represented by formula I1 is selected from one of compounds represented by formulae I1-1 to I1-4 below, said compound represented by formula I2 is selected from one of compounds represented by formulae I2-1 to I2-8 below, and said compound represented by formula I3 is selected from one of compounds represented by formulae I3-1 to I3-8 below, ##STR00047## ##STR00048## ##STR00049## ##STR00050## wherein R.sub.3 and R.sub.4 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.3 and R.sub.4 may be substituted with cyclopentyl, cyclobutyl or cyclopropyl; and each X independently represents CH.sub.2, O or S.

7. The liquid crystal display device according to claim 4, characterized in that said liquid crystal composition further comprises one or more compounds represented by formula III ##STR00051## wherein 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.5 and R.sub.6 may be substituted with cyclopentyl, cyclobutyl, cyclopropyl, or O; ##STR00052## represents one or more of ##STR00053## or any fluorobenzene; and w represents 1, 2 or 3.

8. The liquid crystal display device according to claim 7, characterized in that said one or more compounds represented by formula III are one or more of compounds represented by formulae III-1 to III-5 below: ##STR00054## wherein 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 alkenoxy group having a carbon atom number of 3-6.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0049] The particular embodiments of the present invention will be further described below in detail in conjunction with the drawings.

[0050] FIG. 1 shows a structural schematic diagram of a liquid crystal display panel provided in an embodiment of the present invention.

[0051] FIG. 2 shows a schematic diagram of a liquid crystal alignment direction provided in an embodiment of the present invention.

[0052] FIG. 3 shows a schematic diagram of improved light transmittance provided in an embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

[0053] In order to illustrate the present invention more clearly, the present invention will be further described below in conjunction with preferred embodiments and the accompanying drawings. In the drawings, like parts are represented by the same reference sign. A person skilled in the art would understand that the following contents described in detail are illustrative rather than limiting, and should not limit the scope of protection of the present invention.

[0054] In this description, unless otherwise specified, percentages are weight percentages, temperatures are in degree Celsius ( C.), and the specific meanings of the other symbols and the test conditions are as follows:

[0055] w represents the width of the slit electrodes;

[0056] d represents the width of the electrode gaps between the slit electrodes;

[0057] Cp represents the clearing point of the liquid crystal ( C.), as measured by means of a DSC quantitative method;

[0058] n represents the optical anisotropy, n.sub.o is the refractive index of an ordinary light, n.sub.e is the refractive index of an extraordinary light, and the test conditions are: 252 C., 589 nm and using an abbe refractometer for testing;

[0059] represents the dielectric anisotropy, =.sub..sub., wherein the .sub. is a dielectric constant parallel to a molecular axis, and .sub. is a dielectric constant perpendicular to the molecular axis, and the test conditions are: 250.5 C., using a 20 micron parallel cell, and using INSTEC: ALCT-IR1 for testing;

[0060] 1 represents a rotary viscosity (mPa.Math.s), and the test conditions are: 250.5 C., using a 20 micron parallel cell, and using INSTEC: ALCT-IR1 for testing; and

[0061] Tr (%) represents a transmittance, Tr (%)=100%*bright state (Vop) luminance/light source luminance, the test equipment is DMS501, and the test conditions are 250.5 C.; since .sub. positively correlated with Tr, when inspecting the transmittance, c can be used as an inspection indicator to testify.

[0062] In the embodiments of the present invention, liquid crystal monomer structures are represented by codes, wherein the codes of cyclic structures, end groups and linking groups of liquid crystals are represented, as shown in tables 1 and 2 below.

TABLE-US-00001 TABLE 1 Corresponding code for ring structure Ring structure Corresponding code [00020] C [00021] P [00022] G [00023] U [00024] GI [00025] Y [00026] PI [00027] HHPY [00028] N [00029] M [00030] A [00031] D [00032] BHHO-m-nFF [00033] DFDBF-m-m [00034] B(S)

TABLE-US-00002 TABLE 2 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 CHCH V CC T COO Z CHCHC.sub.nH.sub.2n+1 -Vn [00035] C(5) [00036] C(4) [00037] C(3)1

EXAMPLES

[0063] ##STR00038##

[0064] The following specific embodiments are used to illustrate the present invention. The liquid crystal compositions provided in the embodiments of the present invention can be produced using a method of mixing liquid crystal compounds, e.g., a method of mixing different components at a high temperature and dissolving same in each other, and the liquid crystal compositions provided in the embodiments of the present invention may also be prepared according to other conventional methods, e.g., heating, ultrasonic wavesuspension and so on. The above-mentioned methods are all conventional methods, unless otherwise specified. The raw materials for preparing the liquid crystal compositions are all available from public commercial approaches, unless otherwise specified.

Example 1

[0065] In this example, the width of the slit electrodes is designed to be 4 m, the electrode gap is designed to be 2 m, and the ratio of the width of the slit electrode to the width of the electrode gap is 1:0.5.

[0066] The formulation of the liquid crystal composition and the design of the liquid crystal display device are as shown in table 3 below.

TABLE-US-00003 TABLE 3 Formulation of liquid crystal composition and design of liquid crystal display device of Example 1 Category Liquid crystal monomer code Content (%) III 3-CC-V 28.00 III 3-CC-V1 10.00 III 3-CC-5 4.00 II 2-CCOY-O2 10.00 II 3-CCOY-O2 10.00 II 4-CCOY-O2 10.00 I DFDBF-Cp1O-O4 2.00 I DFDBF-Cp1O-O5 2.50 I 3-PUQY-O2 5.00 I 3-PUQY-O4 4.50 II 2-PYP-1Cpr 6.00 I BHHO-Cp1O-O4FF 8.00 d = 4 m w = 2 m [1 KHz, 25 C.]: 3.83 .sub.: 7.86 n [589 nm, 25 C.]: 0.1006 Cp: 84.6 C. .sub.1 [25 C.]: 128 m Pa .Math. s.

Example 2

[0067] In this example, the width of the slit electrodes is designed to be 3 m, the electrode gap is designed to be 6 m, and the ratio of the width of the slit electrode to the width of the electrode gap is 1:2.

[0068] The formulation of the liquid crystal composition and the design of the liquid crystal display device are as shown in table 4 below.

TABLE-US-00004 TABLE 4 Formulation of liquid crystal composition of and design of liquid crystal display device Example 2 Category Liquid crystal monomer code Content (%) III 3-CC-V 42.00 III 3CC--V1 9.00 III 3-CPP-2V1 9.00 II 2-CCOY-O2 5.00 II 3-CCOY-O2 6.00 II 4-CCOY-O2 5.00 I DFDBF-Cp1O-O4 4.00 I DFDBF-Cp1O-O5 4.00 I 3-PUQY-O2 6.50 I 3-PUQY-O4 6.50 I PGUQY-3-O2 3.00 d = 3 m w = 6 m [1 KHz, 25 C.]: 1.89 .sub.: 5.78 n [589 nm, 25 C.]: 0.0995 Cp: 81.9 C. .sub.1 [25 C.]: 78 m Pa .Math. s.

Comparative Example 1

[0069] In this comparative example, the width of the slit electrodes is designed to be 3 m, and the electrode gap is designed to be 3.5 m.

[0070] The formulation of the liquid crystal composition and the design of the liquid crystal display device are as shown in table 5 below.

TABLE-US-00005 TABLE 5 Formulation of liquid crystal composition and design of liquid crystal display device of Comparative Example 1 Category Liquid crystal monomer code Content (%) III 3-CC-V 28.00 III 3-CC-V1 10.00 III 3-CC-5 4.00 II 2-CCOY-O2 10.00 II 3-CCOY-O2 10.00 II 4-CCOY-O2 10.00 I DFDBF-Cp1O-O4 2.00 I DFDBF-Cp1O-O5 2.50 I 3-PUQY-O2 5.00 I 3-PUQY-O4 4.50 II 2-PYP-1Cpr 6.00 I BHHO-Cp1O-O4FF 8.00 d = 3 m w = 3.5 m [1 KHz, 25 C.]: 3.87 .sub.: 7.55 n [589 nm, 25 C.]: 0.1032 Cp: 84.9 C. .sub.1 [25 C.]: 100 m Pa .Math. s.

Comparative Example 2

[0071] In this comparative example, the width of the slit electrodes is designed to be 3 m, and the electrode gap is designed to be 3.5 m.

[0072] The formulation of the liquid crystal composition and the design of the liquid crystal display device are as shown in table 6 below.

TABLE-US-00006 TABLE 6 Formulation of liquid crystal composition and design of liquid crystal display device of Comparative Example 2 Category Liquid crystal monomer code Content (%) III 3-CPP-2 3.00 III CPP-3-2-V1 9.00 III 3-CC-V 42.00 III 3-CC-V1 9.00 II 2-CCOY-O2 5.00 II 3-CCOY-O2 6.00 II 3-CCOY-O2 5.00 I DFDBF-Cp1O-O4 4.00 I DFDBF-Cp1O-O5 4.00 II 5-PP-O2 6.50 II 2-PYP-1Cpr 6.50 d = 4 m w = 2 m [1 KHz, 25 C.]: 1.78 .sub.: 5.00 n [589 nm, 25 C.]: 0.1027 Cp: 80.9 C. .sub.1 [25 C.]: 58 m Pa .Math. s.

[0073] In Example 1 and Comparative Example 1 the same liquid crystal composition is used, but different liquid crystal display device design schemes are used; and in Example 1 and Comparative Example 2, the same liquid crystal display device design scheme is used, but different liquid crystal compositions are used. The above-mentioned examples and comparative examples are subjected to transmission testing: At a working voltage equal to 6 V, the transmittance of Example 1 is higher than that of Comparative Example 1 by about 3.0%, and at a working voltage equal to 10 V, the transmittance of Example 2 is higher than that of Comparative Example 2 by about 4.0%. By using the liquid crystal composition provided by the present invention to work with a liquid crystal display device, a higher transmittance is obtained, so that the liquid crystal display device achieves the effect of having a higher luminance or the effect of energy saving and power saving.

[0074] FIG. 1 is a schematic diagram of a liquid crystal display panel provided in an 0.0 embodiment of the present invention, which mainly comprises: a liquid crystal composition 21, an array substrate 22 and an opposite substrate 23 arranged facing the array substrate. Specifically, the array substrate 22 comprises a first transparent substrate 221, and slit electrodes 222 for applying a voltage; and the opposite substrate 23 comprises a second transparent substrate 231, and a bulk electrode 232 for applying a voltage.

[0075] As shown in FIG. 2, unlike the comparative examples, the liquid crystal compositions of the examples have a better alignment direction under the action of an electric field, and the alignment direction thereof more tends to be horizontal, which improves the deflection effect of the liquid crystal on light.

[0076] As shown in FIG. 3, on the basis of FIG. 2, it is indicated in further detail that there are different transmittances at different positions of the slit electrode structure; in the position where the transmittance of the comparative example is lower, the example has a higher transmittance; overall, the example achieves a higher transmittance.

[0077] Obviously, the above-mentioned embodiments of the present invention are merely examples for clearly illustrating the present invention, rather than limiting the embodiments of the present invention; for a person of ordinary skill in the art, other variations or changes in different forms may also be made on the basis of the above description, all the embodiments cannot be provided exhaustively herein, and any obvious variation or change derived from the technical solution of the present invention is still within the scope of protection of the present invention.