Negative dielectric anisotropy liquid crystal composition and liquid crystal display device
阅读说明：本技术 负介电各向异性液晶组合物及液晶显示器件 (Negative dielectric anisotropy liquid crystal composition and liquid crystal display device ) 是由 舒克伦 尹硕 刘永祥 赖育宏 丰佩川 于 2021-08-17 设计创作，主要内容包括：本发明涉及负介电各向异性液晶组合物及液晶显示器件。本发明的负介电各向异性液晶组合物包含：至少一种式I所示化合物、至少一种式Ⅱ所示化合物以及至少一种式Ⅲ所示化合物。与现有技术相比,本发明的液晶组合物获得了在维持合适的光学各向异性值、介电各向异性的基础上具有良好的响应速度及高的透过率的技术效果。(The invention relates to a negative dielectric anisotropy liquid crystal composition and a liquid crystal display device. The negative dielectric anisotropic liquid crystal composition of the present invention comprises: at least one compound shown as a formula I, at least one compound shown as a formula II and at least one compound shown as a formula III. Compared with the prior art, the liquid crystal composition has the technical effects of good response speed and high transmittance on the basis of maintaining proper optical anisotropy value and dielectric anisotropy.)
1. A negative dielectric anisotropy liquid crystal composition, comprising:
at least one compound represented by formula I;
at least one compound represented by formula II; and the number of the first and second groups,
at least one compound of formula III;
in the formula I, R1、R2Each independently represents a hydrogen atom, a linear alkyl group having 1 to 8 carbon atoms, a linear alkoxy group having 1 to 8 carbon atoms, a linear alkenyl group having 2 to 8 carbon atoms, or a linear alkenyloxy group having 2 to 8 carbon atoms, wherein one or two of them are not adjacent to each other2-optionally substituted by-O-, any H being optionally substituted by a F atom;
ring a1 is selected from the group consisting of: 1, 4-cyclohexylene, cyclohexene-1, 4-diyl, 1, 4-phenylene, 2-fluoro-1, 4-phenylene, 2, 3-difluoro-1, 4-phenylene, oxacyclohexane-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, 1-methylcyclohexane-1, 4-diyl, 2-methylbenzene-1, 4-diyl;
z represents a single bond, -C2H2-、-C2H4-、-C2H2CH2O-、-OCH2C2H2-、-CH2O-、-OCH2-、-C2H2CH2S-、-SCH2C2H2-、-CH2S-、-SCH2-、-O-、-S-、-CF2O-、-OCF2-, -C.ident.C-, -OOC-or-COO-, in which-CH2O-、-C2H2-、-C2H4-、-C2H2CH2O-、-OCH2C2H2-any H in (a) is optionally substituted with F;
x represents-O-, -S-, -SO-, -SOO-, -CF2-, -CO-or-CH2-；
Y1、Y2Each independently represents-F-, -CH2F-、-CHF2-、-CF3-、-OCH2F-、-OCHF2-or-OCF3-；
n represents 0, 1, 2 or 3;
in the formula II, R3、R4Each independently represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms; and, R3、R4Each independently of the other, H on any carbon atom in (a) is optionally substituted with F;
ring C, ring D are each independently selected from the group consisting of: 1, 4-cyclohexylene, cyclohexene-1, 4-diyl, 1, 4-phenylene, 2-fluoro-1, 4-phenylene, 2, 3-difluoro-1, 4-phenylene, oxacyclohexane-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, 1-methylcyclohexane-1, 4-diyl, 2-methylbenzene-1, 4-diyl;
p represents 0, 1, 2 or 3;
in the formula III, R5、R6Each independently represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms; and, R5、R6Each independently of the other, H on any carbon atom in (a) is optionally substituted with F;
Z3represents a single bond or-CH2O-；
q and r each independently represent 0, 1 or 2;
ring E, ring F are each independently selected from the group consisting of: 1, 4-cyclohexylene, cyclohexene-1, 4-diyl, 1, 4-phenylene, 2-fluoro-1, 4-phenylene, 2, 3-difluoro-1, 4-phenylene, oxacyclohexane-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, 1-methylcyclohexane-1, 4-diyl, 2-methylbenzene-1, 4-diyl.
2. The negative dielectric anisotropic liquid crystal composition of claim 1, wherein the compound of formula I is selected from the group consisting of compounds of formulae IA to IN and formulae Ia to INGroup of (I) wherein R1、R2The definitions are the same as in claim 1,
3. the negative dielectric anisotropic liquid crystal composition of claim 2, wherein R1R represents a linear alkyl group having 1 to 8 carbon atoms or a linear alkenyl group having 1 to 8 carbon atoms2Represents a linear alkoxy group having 1 to 8 carbon atoms or a linear alkenyloxy group having 2 to 8 carbon atoms.
4. The negative dielectric anisotropic liquid crystal composition of any one of claims 1 to 3, wherein the compound represented by formula II is selected from the group consisting of the following compounds represented by formulae II-1 to II-10:
R3、R4each independently represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms; r3、R4Each hydrogen on any carbon atom in (a) is independently optionally substituted with fluorine;
(F) represents F or H.
5. The negative dielectric anisotropic composition of any one of claims 1 to 4, wherein the compound represented by formula III is selected from the group consisting of compounds represented by formulae III-1 to III-17 below:
R5、R6each independently represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms, and R5、R6Each independently of the other, is optionally substituted with F.
6. The negative dielectric anisotropic liquid crystal composition of any one of claims 1 to 5, wherein the liquid crystal composition further comprises one or more compounds represented by formulae IV-1 to IV-50 below:
wherein R is1' represents H or an alkyl group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms, and optionally 4 or less of H are substituted by F;
R2' represents H or alkyl having 1 to 8 carbon atoms or alkenyl having 2 to 8 carbon atoms, wherein one or two non-adjacent-CH2-is optionally substituted by-O-, and optionally 4 or fewer H are substituted by F.
7. The negative dielectric anisotropic liquid crystal composition of any one of claims 1 to 6, wherein the liquid crystal composition further comprises one or more compounds represented by formulas V-1 to V-78 as follows:
8. the negative dielectric anisotropic liquid crystal composition of any one of claims 1 to 7, wherein the liquid crystal composition further comprises one or more compounds represented by the following formulae vi-1 to vi-8:
9. the negative dielectric anisotropic liquid crystal composition according to any one of claims 1 to 8, wherein the amount of the compound represented by formula I is 1 to 30 parts by mass, the amount of the compound represented by formula II is 1 to 60 parts by mass, the amount of the compound represented by formula III is 1 to 60 parts by mass, the amount of the compound represented by formula IV is 0 to 40 parts by mass, the amount of the compound represented by formula V is 0 to 20 parts by mass, and the amount of the compound represented by formula VI is 0 to 1.00 parts by mass, based on 100 parts by mass of the negative dielectric anisotropic liquid crystal composition.
10. A liquid crystal display device, wherein the liquid crystal composition comprises the liquid crystal composition according to any one of claims 1 to 9; the liquid crystal display device is an active matrix display device or a passive matrix display device.
11. The liquid crystal display device of claim 10, wherein the liquid crystal display device is driven in a PS-VA mode, a VA mode, an IPS mode, an FFS mode, a PS-IPS mode, a PS-FFS mode, or an ECB mode.
Technical Field
The invention relates to the technical field of liquid crystal materials. And more particularly, to a liquid crystal composition and a liquid crystal display device.
Background
Liquid crystal display devices are used in various household electric appliances, industrial measuring instruments, automobile panels, mobile phones, smart phones, notebook personal computers, tablet PCs, televisions, and the like, as typified by clocks and desktop computers. Representative examples of liquid crystal display systems include: twisted Nematic (TN) type, Super Twisted Nematic (STN) type, guest-host (GH) type, in-plane switching (IPS) type, Fringe Field Switching (FFS) type, Optically Compensated Birefringence (OCB) type, Electrically Controlled Birefringence (ECB) type, Vertically Aligned (VA) type, Color Super Homeotropic (CSH) type, Ferroelectric Liquid Crystal (FLC) type, and the like. The driving method may be static driving, multiplex driving, simple matrix driving, or Active Matrix (AM) driving by a Thin Film Transistor (TFT), a Thin Film Diode (TFD), or the like. Among these display modes, it is known that when a liquid crystal composition (n-type liquid crystal composition) exhibiting a negative dielectric anisotropy is used, the IPS mode, FFS mode, ECB mode, VA mode, CSH mode, and the like exhibit favorable characteristics.
The display modes using the n-type liquid crystal composition include a vertical Alignment mode represented by a Polymer Stabilized Alignment (PSA) type or a Polymer Stabilized vertical Alignment (PS-VA) type in which Alignment is controlled by polymerizing a VA-type or a polymerizable compound in a liquid crystal phase, and a horizontal Alignment mode represented by an IPS-type or FFS-type. The vertical alignment method is characterized by a wide viewing angle, high transmittance, high contrast, and a high response speed, and is mainly used for large-sized display devices such as Televisions (TVs) and monitors. On the other hand, the horizontal alignment method is adopted in mobile devices such as smartphones and tablet PCs, and is also being adopted in liquid crystal televisions from the viewpoint of a wide viewing angle, high transmittance, low power consumption, and optimality with respect to touch panels. The PSA type or PS-VA type liquid crystal display device is a device in which a polymer structure is formed in a cell in order to control the pretilt angle of liquid crystal molecules.
In recent years, with the progress of high resolution, high frequency driving, and the like of liquid crystal TVs, there has been an increasing demand for liquid crystal compositions that are suitable for high-performance liquid crystal devices and can satisfy various characteristics.
Further, there is a problem that a liquid crystal composition containing a polymerizable compound, which has been conventionally used to contain a polymerizable compound in a liquid crystal composition, does not have characteristics capable of coping with a high-resolution liquid crystal TV such as 4K or 8K. In particular, a high-resolution liquid crystal display device requires high-definition pixels each having a small size. Since the area of the wiring and the light shielding portion is relatively increased, Ultraviolet (UV) light is largely blocked, and the aperture ratio of the liquid crystal display portion is reduced, thereby lowering the transmittance.
In particular, in the case of a vertical alignment liquid crystal display device (hereinafter, sometimes referred to as "VA liquid crystal display device"), it is difficult to sufficiently improve light transmittance only by adjusting the threshold voltage. By shifting (shift) the V-T curve showing the characteristics of applied voltage-transmittance to the low voltage side by lowering the threshold voltage, the transmittance under the low voltage condition can be improved. However, in the above method, the slope of the V-T curve of the VA liquid crystal display device does not become steep, and the maximum transmittance does not become high, so that it is difficult to achieve high light transmittance at a middle-order or higher driving voltage.
Adjustment of splay elastic constant (K) of a liquid crystal composition constituting a liquid crystal layer can be considered11) And bending elastic constant (K)33) Is K11/K33The method of (2). By adjusting so that K11/K33The value of (3) is reduced, the V-T curve of the corresponding VA liquid crystal display device becomes steep, and the light transmittance can be improved even if the driving voltage is higher than the medium-order.
In addition, in liquid crystal TVs of higher models and the like, high-frequency driving is progressing, and therefore development of a liquid crystal composition capable of responding to voltage change at high speed is urgently required. In order to respond to the voltage change at high speed, it is desirable that G as a parameter that governs the response speed in a liquid crystal display device of a vertical alignment mode (such as VA mode or the like)1/K33The value of (c) is small. In a horizontal alignment mode (e.g. IPS mode)Etc.), G is preferably used as a parameter that governs the response speed1/K11The value of (c) is small.
Disclosure of Invention
The present inventors have further studied and found that a negative dielectric anisotropic liquid crystal composition containing the liquid crystal compounds represented by the above formulas I, II and III according to the present invention has a reduced K value in consideration of various characteristics such as dielectric anisotropy (. DELTA.. di-elect cons.), optical anisotropy and the like11/K33、G1/K33、G1/K11The value is obtained. In a liquid crystal display device of a vertical alignment mode (e.g., VA mode, etc.)11/K33、G1/K33Has a small value of K in a liquid crystal display device of a horizontal alignment mode (e.g., IPS mode, etc.)11/K33、G1/K11The values of (A) are all small, and when the liquid crystal display device is used for liquid crystal devices such as liquid crystal TVs, quick response and high transmittance can be realized. Thus, the present invention has been completed.
In one aspect, the present invention provides a negative dielectric anisotropic liquid crystal composition comprising:
at least one compound represented by formula I;
at least one compound represented by formula II; and the number of the first and second groups,
at least one compound of formula II I,
in the formula I, R1、R2Each independently represents a hydrogen atom, a linear alkyl group having 1 to 8 carbon atoms, a linear alkoxy group having 1 to 8 carbon atoms, a linear alkenyl group having 2 to 8 carbon atoms, or a linear alkenyloxy group having 2 to 8 carbon atoms, wherein one or two of them are not adjacent to each other2-optionally substituted by-O-, wherein any H is optionally substituted by a F atom;
ring a1 is selected from the group consisting of: 1, 4-cyclohexylene, cyclohexene-1, 4-diyl, 1, 4-phenylene, 2-fluoro-1, 4-phenylene, 2, 3-difluoro-1, 4-phenylene, oxacyclohexane-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, 1-methylcyclohexane-1, 4-diyl, 2-methylbenzene-1, 4-diyl;
z represents a single bond, -C2H2-、-C2H4-、-C2H2CH2O-、-OCH2C2H2-、-CH2O-、-OCH2-、-C2H2CH2S-、-SCH2C2H2-、-CH2S-、-SCH2-、-O-、-S-、-CF2O-、-OCF2-, -C.ident.C-, -OOC-or-COO-, in which-CH2O-、-C2H2-、-C2H4-、-C2H2CH2O-、-OCH2C2H2-any H in (a) is optionally substituted with F;
x represents-O-, -S-, -SO-, -SOO-, -CF2-, -CO-or-CH2-；
Y1、Y2Each independently represents-F-, -CH2F-、-CHF2-、-CF3-、-OCH2F-、-OCHF2-or-OCF3-；
n represents 0, 1, 2 or 3;
in the formula II, R3、R4Each independently represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms; and, R3、R4Each independently of the other, H on any carbon atom in (a) is optionally substituted with F;
ring C, ring D are each independently selected from the group consisting of: 1, 4-cyclohexylene, cyclohexene-1, 4-diyl, 1, 4-phenylene, 2-fluoro-1, 4-phenylene, 2, 3-difluoro-1, 4-phenylene, oxacyclohexane-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, 1-methylcyclohexane-1, 4-diyl, 2-methylbenzene-1, 4-diyl;
p represents 0, 1, 2 or 3.
In the formula III, R5、R6Each is independentThe alkyl group having 1 to 5 carbon atoms, the alkoxy group having 1 to 5 carbon atoms, the alkenyl group having 2 to 5 carbon atoms, or the alkenyloxy group having 2 to 5 carbon atoms; and, R5、R6Each independently of the other, H on any carbon atom in (a) is optionally substituted with F;
Z3represents a single bond or-CH2O-；
q and r each independently represent 0, 1 or 2;
ring E, ring F are each independently selected from the group consisting of: 1, 4-cyclohexylene, cyclohexene-1, 4-diyl, 1, 4-phenylene, 2-fluoro-1, 4-phenylene, 2, 3-difluoro-1, 4-phenylene, oxacyclohexane-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, 1-methylcyclohexane-1, 4-diyl, 2-methylbenzene-1, 4-diyl.
In another aspect, the present invention provides a liquid crystal display device comprising the liquid crystal composition of the present invention; the liquid crystal display device is an active matrix display device or a passive matrix display device.
Effects of the invention
By using the negative dielectric anisotropic liquid crystal composition of the present invention containing the liquid crystal compounds represented by the formulae I, II and III, the K is reduced while satisfying all the properties required for the liquid crystal composition having negative dielectric anisotropy11/K33、G1/K33、G1/K11Accordingly, a liquid crystal display device using the negative dielectric anisotropy liquid crystal composition of the present invention can realize a fast response and a high transmittance. The negative dielectric anisotropic liquid crystal composition of the present invention can obtain reduced G in a vertical alignment mode (e.g., VA, PS-VA)1/K33And a parameter that governs steepness of the electro-optic effect, namely, K11/K33Reduced to have an improved response speed and excellent transmittance. The negative dielectric constant anisotropic liquid crystal composition of the present invention can obtain a reduced G in a liquid crystal display device in a horizontal alignment mode (e.g., IPS)1/K11And dominates the electro-optical effectParameter of desired steepness, i.e. K33/K11Is large, thereby having an improved response speed and excellent transmittance.
Further, the liquid crystal composition of the present invention can achieve high-speed response, good low-temperature storage stability, and high transmittance when used in a VA liquid crystal display device or a PS-VA display device.
Detailed Description
[ liquid Crystal composition ]
The negative dielectric anisotropic liquid crystal composition of the present invention comprises:
at least one compound represented by formula I;
at least one compound represented by formula II; and the number of the first and second groups,
at least one compound represented by formula III.
In the formula I, R1、R2Each independently represents a hydrogen atom, a linear alkyl group having 1 to 8 carbon atoms, a linear alkoxy group having 1 to 8 carbon atoms, a linear alkenyl group having 2 to 8 carbon atoms, or a linear alkenyloxy group having 2 to 8 carbon atoms, wherein one or two of them are not adjacent to each other2-is optionally substituted by-O-, wherein any H is optionally substituted by a F atom.
Examples of the "straight-chain alkyl group having 1 to 8 carbon atoms" include methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, and n-octyl groups.
Examples of the "linear alkoxy group having 1 to 8 carbon atoms" include methoxy group, ethoxy group, n-propoxy group, n-butoxy group, n-pentoxy group, n-hexoxy group, n-heptoxy group, and n-octoxy group.
Examples of the "linear alkenyl group having 2 to 8 carbon atoms" include vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 1-heptenyl, 2-heptenyl, 3-heptenyl, 1-octenyl, 2-octenyl and 3-octenyl.
Examples of the "linear alkenyloxy group having 2 to 8 carbon atoms" include an vinyloxy group, a 1-propenyloxy group, a 2-propenyloxy group, a 1-butenyloxy group, a 2-butenyloxy group, a 3-butenyloxy group, a 1-pentenyloxy group, a 2-pentenyloxy group, a 1-hexenyloxy group, a 2-hexenyloxy group, a 3-hexenyloxy group, a 1-heptenyloxy group, a 2-heptenyloxy group, a 3-heptenyloxy group, a 1-octenyloxy group, a 2-octenyloxy group, and a 3-octenyloxy group.
The aforementioned "one or two non-adjacent-CHs2The term "optionally substituted with-O" means any of-CH in the straight-chain alkyl group having 1 to 8 carbon atoms, the straight-chain alkoxy group having 1 to 8 carbon atoms, the straight-chain alkenyl group having 2 to 8 carbon atoms and the straight-chain alkenyloxy group having 2 to 8 carbon atoms2-is optionally substituted with-O-, but adjacent-CH2Are not simultaneously substituted.
The phrase "any H is optionally substituted with an F atom" means that the number of F substitutions is not limited and may be monofluoro, polyfluoro, or perfluoro.
Preferably, the aforementioned R1Represents a hydrogen atom, a linear alkyl group having 1 to 5 carbon atoms, a linear alkoxy group having 1 to 5 carbon atoms, a linear alkenyl group having 2 to 5 carbon atoms, or a linear alkenyloxy group having 2 to 5 carbon atoms, wherein one or two of them are not adjacent to each other2-optionally substituted by-O-, any H being optionally substituted by a F atom.
Examples of the "linear alkyl group having 1 to 5 carbon atoms" include methyl, ethyl, n-propyl, n-butyl, n-pentyl and the like. Preferably methyl, ethyl or n-propyl.
Examples of the "linear alkoxy group having 1 to 5 carbon atoms" include methoxy group, ethoxy group, n-propoxy group, n-butoxy group and n-pentoxy group. Preferably methoxy, ethoxy or n-propoxy.
Examples of the "straight-chain alkenyl group having 2 to 5 carbon atoms" include vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl and 3-pentenyl. Preferably vinyl, 1-propenyl, 3-butenyl, or 3-pentenyl.
Examples of the "linear alkenyloxy group having 2 to 5 carbon atoms" include an vinyloxy group, a 1-propenyloxy group, a 2-propenyloxy group, a 1-butenyloxy group, a 2-butenyloxy group, a 3-butenyloxy group, a 1-pentenyloxy group, a 2-pentenyloxy group and a 3-pentenyloxy group. Preferably an ethyleneoxy group, a 1-propyleneoxy group, a 3-butyleneoxy group, or a 3-penteneoxy group.
One or two non-adjacent-CH groups among the C1-5 linear alkyl group, C1-5 linear alkoxy group, C2-5 linear alkenyl group, or C2-5 linear alkenyloxy group2-optionally substituted by-O-, any H being optionally substituted by a F atom.
The aforementioned ring a1 is selected from the group consisting of: 1, 4-cyclohexylene, cyclohexene-1, 4-diyl, 1, 4-phenylene, 2-fluoro-1, 4-phenylene, 2, 3-difluoro-1, 4-phenylene, oxacyclohexane-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, 1-methylcyclohexane-1, 4-diyl, 2-methylbenzene-1, 4-diyl;
the aforementioned 2-fluoro-1, 4-phenylene group represents 2 divalent groups in which a fluorine substituent may be located on the left or right. Other similar groups also apply to this rule.
In some embodiments of compounds of formula I, ring A1 is preferably 1, 4-cyclohexylene, cyclohexene-1, 4-diyl, or 1, 4-phenylene, more preferably 1, 4-cyclohexylene.
In some embodiments of the compounds of formula I, Z preferably represents a single bond, -C2H2-, or-C2H4-, more preferably a single bond.
In some embodiments of the compounds of formula I, X is preferably-O-or-S-.
Conversion of formula IIn some embodiments of the compound, Y1、Y2Each independently represents-F-, -CH2F-、-CHF2-、-CF3-、-OCH2F-、-OCHF2-or-OCF3-。
In formula I, n represents 0, 1, 2, or 3, and in view of obtaining a smaller response index value and having a faster response time, n is preferably 0, 1, or 2, and more preferably n is 0 or 1.
IN the liquid crystal compound having negative dielectric anisotropy of the present invention, it is preferably selected from the group consisting of compounds represented by the following formulae IA to IN, and IA to IN.
IN the compounds represented by IA to IN and Ia to IN, R1Preferably a C1-8 linear alkyl group or a C2-8 linear alkenyl group. R1More preferably methyl, ethyl, n-propyl, ethenyl or propenyl.
IN the compounds represented by IA to IN and Ia to IN, R2Preferably a linear alkoxy group having 1 to 8 carbon atoms or a linear alkenyloxy group having 2 to 8 carbon atoms. R2Further preferred is a methoxy group, an ethoxy group, a propoxy group, a propenyloxy group or a butenyloxy group.
The structural formula of the compound shown in the formula II is shown as follows.
In the formula II, R3、R4Each independently represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms; and, R3、R4Each independently of the other, H on any carbon atom in (a) is optionally substituted with F;
ring C, ring D are each independently selected from the group consisting of: 1, 4-cyclohexylene, cyclohexene-1, 4-diyl, 1, 4-phenylene, 2-fluoro-1, 4-phenylene, 2, 3-difluoro-1, 4-phenylene, oxacyclohexane-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, 1-methylcyclohexane-1, 4-diyl, 2-methylbenzene-1, 4-diyl;
p represents 0, 1, 2 or 3.
As the aforementioned R3、R4The "alkyl group having 1 to 5 carbon atoms" independently of each other may be a straight-chain alkyl group, a branched-chain alkyl group, or a cyclic alkyl group, and is preferably a straight-chain alkyl group. Examples of such a straight-chain alkyl group include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Examples of the branched alkyl group include an isopropyl group, an isobutyl group, and a tert-butyl group. Examples of the cyclic alkyl group include cyclopropyl, cyclobutyl, cyclopentyl, methylcyclopropyl, and methylcyclobutyl.
As the aforementioned R3、R4Examples of the "alkoxy group having 1 to 5 carbon atoms" which are independently represented include methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, n-pentoxy group, and tert-pentoxy group.
As the aforementioned R3、R4Examples of the "alkenyl group having 2 to 5 carbon atoms" which are independently represented include an ethenyl group, a propenyl group, a butenyl group, a 2-methylpropenyl group, a 1-pentenyl group, a 2-methyl-1-butenyl group, a 3-methyl-1-butenyl group, and a 2-methyl-2-butenyl group.
As the aforementioned R3、R4Examples of the "alkenyloxy group having 2 to 5 carbon atoms" which are independently represented include an vinyloxy group, a propenyloxy group, a butenyloxy group, a 2-methylpropenyloxy group, a 1-pentenyloxy group, a 2-methyl-1-butenyloxy group, a 3-methyl-1-butenyloxy group, and a 2-methyl-2-butenyloxy group.
The compound represented by the above formula II is preferably selected from the group consisting of the compounds represented by the following formulae II-1 to II-10. Wherein R is3、R4The definitions of (a) are the same as those described above.
(F) Represents F or H.
The structural formula of the compound shown in the formula III is shown as follows.
In the formula III, R5、R6Each independently represents an alkyl group having 1 to 5 carbon atoms, an alkoxy group having 1 to 5 carbon atoms, an alkenyl group having 2 to 5 carbon atoms, or an alkenyloxy group having 2 to 5 carbon atoms; and, R5、R6Each independently of the other, H on any carbon atom in (a) is optionally substituted with F;
Z3represents a single bond or-CH2O-；
q and r each independently represent 0, 1 or 2;
ring E, ring F are each independently selected from the group consisting of: 1, 4-cyclohexylene, cyclohexene-1, 4-diyl, 1, 4-phenylene, 2-fluoro-1, 4-phenylene, 2, 3-difluoro-1, 4-phenylene, oxacyclohexane-2, 5-diyl, 1, 3-dioxane-2, 5-diyl, 1-methylcyclohexane-1, 4-diyl, 2-methylbenzene-1, 4-diyl.
Preferably, the aforementioned compound represented by the formula III is selected from the group consisting of the compounds represented by the formulae III-1 to III-17 described below. Wherein R is5、R6The definitions of (a) are the same as those described above.
As the aforementioned R5、R6The "alkyl group having 1 to 5 carbon atoms" independently of each other may be a straight-chain alkyl group, a branched-chain alkyl group, or a cyclic alkyl group, and is preferably a straight-chain alkyl group. Examples of such a straight-chain alkyl group include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, and an n-pentyl group. Examples of the branched alkyl group include an isopropyl group, an isobutyl group, and a tert-butyl group. Examples of the cyclic alkyl group include cyclopropyl, cyclobutyl, cyclopentyl, methylcyclopropyl, and methylcyclobutyl.
As the aforementioned R5、R6Examples of the "alkoxy group having 1 to 5 carbon atoms" which are independently represented include methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, n-pentoxy group, and tert-pentoxy group.
As the aforementioned R5、R6Examples of the "alkenyl group having 2 to 5 carbon atoms" which are independently represented include an ethenyl group, a propenyl group, a butenyl group, a 2-methylpropenyl group, a 1-pentenyl group, a 2-methyl-1-butenyl group, a 3-methyl-1-butenyl group, and a 2-methyl-2-butenyl group.
As the aforementioned R5、R6Examples of the "alkenyloxy group having 2 to 5 carbon atoms" independently of each other include an ethyleneoxy group, a propyleneoxy group, a butyleneoxy group, a 2-methylpropenyloxy group, a 1-penteneoxy group, a 2-penteneoxy group, and a 2-methyl-1-buteneoxy group3-methyl-1-butenyloxy, 2-methyl-2-butenyloxy and the like.
In one embodiment of the negative dielectric anisotropy liquid crystal composition, the compound represented by the formula I, the compound represented by the formula II, and the compound represented by the formula III may be contained, for example, in the following proportions: the amount of the compound represented by the formula I is 1 to 30 parts by mass, the amount of the compound represented by the formula II is 1 to 60 parts by mass, and the amount of the compound represented by the formula III is 1 to 60 parts by mass, based on 100 parts by mass of the liquid crystal composition.
Some embodiments of the negative dielectric anisotropic liquid crystal composition of the present invention may further comprise compounds represented by the following formulae IV-1 to IV-50:
wherein R is1' represents H or an alkyl group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms, and optionally 4 or less of H are substituted by F;
R2' represents H or alkyl having 1 to 8 carbon atoms or alkenyl having 2 to 8 carbon atoms, wherein one or two non-adjacent-CH2-is optionally substituted by-O-, and optionally 4 or fewer H are substituted by F.
The compounds shown in the formulas IV-1 to IV-50 in the negative dielectric anisotropy liquid crystal composition are optional components. The components of the negative dielectric anisotropic liquid crystal composition according to some embodiments may be in a mass ratio of 1 to 30 parts by mass of the compound represented by formula I, 1 to 60 parts by mass of the compound represented by formula II, 1 to 60 parts by mass of the compound represented by formula III, and 0 to 20 parts by mass of the compound selected from the group consisting of the compounds represented by formulae IV-1 to IV-50, with respect to 100 parts by mass of the negative dielectric anisotropic liquid crystal composition.
In some embodiments of the negative dielectric anisotropic liquid crystal composition of the present invention, one or more of the following compounds represented by formulas V-1 to V-78 may be further contained:
the compounds represented by the aforementioned formulas V-1 to V-78 in the negative dielectric anisotropy liquid crystal composition are optional components. The components of the negative dielectric anisotropic liquid crystal composition according to some embodiments may be in a mass ratio of 1 to 30 parts by mass of the compound represented by formula I, 1 to 60 parts by mass of the compound represented by formula II, 1 to 60 parts by mass of the compound represented by formula III, 0 to 20 parts by mass of a compound selected from the group consisting of the compounds represented by formulae IV-1 to IV-50, and 0 to 20 parts by mass of the compound represented by formulae V-1 to V-78, with respect to 100 parts by mass of the negative dielectric anisotropic liquid crystal composition.
Some embodiments of the negative dielectric anisotropic liquid crystal composition of the present invention may further comprise one or more compounds represented by the following formulas VI-1 to VI-8:
the compounds represented by the formulas VI-1 to VI-8 in the negative dielectric anisotropy liquid crystal composition are optional components. The components of the negative dielectric anisotropic liquid crystal composition according to some embodiments may be in a mass ratio of 1 to 30 parts by mass of the compound represented by formula I, 1 to 60 parts by mass of the compound represented by formula II, 1 to 60 parts by mass of the compound represented by formula III, 0 to 20 parts by mass of the compound selected from the group consisting of the compounds represented by formulae IV-1 to IV-50, 0 to 20 parts by mass of the compounds represented by formulae V-1 to V-78, and 0 to 1.00 parts by mass of the compounds represented by formulae VI-1 to VI-8, with respect to 100 parts by mass of the negative dielectric anisotropic liquid crystal composition.
In the negative dielectric anisotropic liquid crystal composition of the present invention, various functional additives may be optionally added, and these additives may be exemplified by, for example, a UV stabilizer, an antioxidant, a chiral dopant, a polymerization initiator, and may contain one or more of them.
The antioxidant may be exemplified by:
m represents an integer of 1 to 10;
as the chiral dopant, for example,
wherein R is0Represents an alkyl group having 1 to 10 carbon atoms;
examples of the light stabilizer include, for example,
wherein Z is0Represents an alkylene group having 1 to 20 carbon atoms, wherein any one or more hydrogen atoms in the alkylene group are optionally substituted by halogen, and any one or more-CH groups2-is optionally substituted by-O-.
Examples of the ultraviolet absorber include,
wherein R is01Represents an alkyl group having 1 to 10 carbon atoms.
When the additive is contained, the amount thereof to be added may be, for example, 0.01% to 1.5% of the total mass of the liquid crystal composition.
[ liquid Crystal display device ]
The second aspect of the present invention provides a liquid crystal display device using the aforementioned negative dielectric anisotropy liquid crystal composition of the present invention. The liquid crystal display device of the present invention is not particularly limited as long as it contains the liquid crystal composition described above. Those skilled in the art will be able to select other compositions and structures of the liquid crystal display device as appropriate depending on the desired properties.
The liquid crystal display device of the present invention is preferably driven in a PS-VA mode, IPS mode, FFS mode, PS-IPS mode, PS-FFS mode, or ECB mode.
Examples
In order to more clearly illustrate the invention, the invention is further described below in connection with preferred embodiments. It is to be understood by persons skilled in the art that the following detailed description is illustrative and not restrictive, and is not to be taken as limiting the scope of the invention.
In the invention, the preparation method is a conventional method unless otherwise specified, the used raw materials can be obtained from a public commercial way unless otherwise specified, the percentages refer to mass percentage, the temperature is centigrade (DEG C), and the liquid crystal compound is also a liquid crystal monomer.
[ liquid Crystal composition having negative dielectric anisotropy ]
In examples and comparative examples, liquid crystal compositions having negative dielectric anisotropy and different compositions were prepared, wherein the monomer structure, the amount (parts by mass) of the specific compound used in each example, and the results of the performance parameter test of the obtained liquid crystal medium are shown in the following tables, respectively.
The temperature units involved in each example are as follows, and the specific meanings and test conditions of other symbols are as follows:
g1(mpa.s) represents the rotational viscosity coefficient of the liquid crystal compound, and the measurement method: the equipment INSTEC comprises ALCT-IR1, a vertical box with the thickness of 18 microns in a test box, the temperature of 25 ℃, and the short term G1;
K11is a torsional elastic constant, K33For the splay spring constant, the test conditions were: at 25 ℃, INSTEC, ALCT-IR1 and 18 micron vertical box;
Δ ε represents dielectric anisotropy, and Δ ε∥-ε⊥Wherein, epsilon∥Is a dielectric constant parallel to the molecular axis,. epsilon⊥For the dielectric constant perpendicular to the molecular axis, test conditions: at 25 ℃, INSTEC, ALCT-IR1 and 18 micron vertical box;
Δ n represents optical anisotropy, and Δ n ═ ne-noWherein n isoRefractive index of ordinary light, neFor the refractive index of extraordinary rays, test conditions: 589nm, 25 + -0.2 deg.C.
VHR represents the voltage holding ratio (%) after ultraviolet irradiation, and the test conditions are 20 +/-2 ℃, voltage +/-5V, pulse width 1ms and voltage holding time 16.7 ms. The test equipment is an ALCT-IV1 liquid crystal performance comprehensive tester. The VHR test uses ultraviolet light with 365nm wavelength and 2.5Mw/cm of irradiation light intensity2Light irradiation was carried out for 34 minutes.
Tni: nematic phase-isotropic liquid phase transition temperature (. degree. C.).
Transmittance: the transmittance was measured when a voltage of 0V to 10V was applied to the liquid crystal display cell. When the transmittance is not less than 97%, the transmittance is evaluated as sufficiently high as good, and when the transmittance is less than 97%, the transmittance is evaluated as low as x.
Low-temperature storage property: after cooling the example of the liquid crystal composition containing the polymerizable compound at-20 ℃ for 240 hours, the presence or absence of the deposition of the polymerizable compound was observed as an index of low-temperature storage stability. The case where no precipitation was observed and no display defects such as bright spots were observed was marked as good, and the case where precipitation was observed was marked as "X".
The preparation method of each negative dielectric anisotropy liquid crystal composition in the examples is as follows: weighing each liquid crystal monomer according to a certain proportion, putting the liquid crystal monomers into a stainless steel beaker, putting the stainless steel beaker filled with each liquid crystal monomer on a magnetic stirring instrument for heating and melting, adding a magnetic rotor into the stainless steel beaker after most of the liquid crystal monomers in the stainless steel beaker are melted, uniformly stirring the mixture, and cooling to room temperature to obtain the liquid crystal composition.
The structures of the liquid crystal monomers used in the examples are represented by the following codes, and the methods for representing the structures of the liquid crystal rings, the terminal groups, and the linking groups are shown in the following tables (one) and (two).
Table (one): corresponding code of ring structure
Table (ii): corresponding codes for end groups and linking groups
Examples are:
liquid crystal compositions of examples 1 to 9 and comparative examples 1 to 2 were prepared in the following formulation ratios shown in tables 1 to 11.
TABLE 1 component proportions of the liquid crystal composition LC-1 of example 1
TABLE 2 component proportions of liquid crystal composition LC-2 of example 2
The compound of the general formula
Liquid crystal structure
Mass portion of
Ⅱ
CC-3-V
35.0
III
CCY-3-O2
10.0
II
CPP-1V-2
8.0
III
CPY-3-O2
5.0
I
LOP[OT,OT]-3-O2
10.0
I
LOP[T,OT]-3-O2V
7.0
I
LSP[T,OT]-3-O2
8.0
II
PP-1-2V1
9.0
III
PYP-2-3
8.0
TABLE 3 component proportioning ratio of liquid crystal composition LC-3 of example 3
TABLE 4 component proportioning ratio of liquid crystal composition LC-4 of example 4
The compound of the general formula
Liquid crystal structure
Mass portion of
Ⅱ
CC-3-V
34.0
III
CCY-3-O2
5.0
I
CLOP[OT,OT]-1V-O2
6.0
I
CLSP[T,F]-1V-O2
6.0
III
COY-3-O2
8.0
III
CPY-3-O2
10.0
II
CPP-1-2V1
6.0
III
CY-3-O2
15.0
II
PP-1-2V1
10.0
TABLE 5 component proportioning ratio of liquid-crystalline medium LC-5 of example 5
TABLE 6 component proportioning ratio of liquid-crystalline medium LC-6 of example 6
The compound of the general formula
Liquid crystal structure
Mass portion of
Ⅱ
CC-3-V
31.0
II
CCP-V-1
5.0
III
C(C4)Y-3-O2
4.0
III
CCY-3-O2
4.0
I
CLOP[T,T]-1V-O2
3.0
I
PLSP[OT,OT]-1V-O2
2.0
III
COY-3-O2
10.0
III
CPY-3-O2
10.0
IV
CVCPY-3-O2
3.0
IV
CV2PYP-1V-O2
3.0
III
CY-3-O2
15.0
II
PP-1-2V1
10.0
TABLE 7 component proportioning ratio of liquid-crystalline medium LC-7 of example 7
TABLE 8 component proportioning ratio of liquid-crystalline medium LC-8 of example 8
The compound of the general formula
Liquid crystal structure
Mass portion of
Ⅱ
CC-3-V
38.0
III
CCY-3-O2
5.0
II
CPP-3-2V1
5.0
I
CLOP[F,T]-1V-O2
5.0
IV
CVCPY-V-O2
4.0
IV
CV2PY-1V-O2
4.0
III
CY-3-O2
15.0
III
CY-3-O4
10.0
III
PYP-2-4
9.0
Ⅴ
CEOB(S)OIC-3-3
5.0
The formulations of comparative example 1 and comparative example 2 are shown in tables 9 and 10 below.
TABLE 9 component ratios of the liquid-crystalline medium C-01 of comparative example 1
TABLE 10 component ratios of the liquid-crystalline medium C-02 of comparative example 2
The compound of the general formula
Liquid crystal structure
Mass portion of
Ⅱ
CC-3-V
26.0
Ⅱ
PP-1-2V
10.0
III
CCOY-2-O2
15.5
III
CY-3-O2
15.0
III
PY-3-O2
6.0
III
CCY-3-O2
11.0
III
CPY-3-O2
7.5
Ⅱ
CPP-1V-2
9.0
The prepared examples and comparative liquid crystal compositions were filled between two substrates of a liquid crystal display for performance testing. The test results are shown in the table below.
TABLE 11 results of performance testing of the examples and comparative liquid crystal compositions
As shown in Table 11 above, the liquid crystal compositions of examples 1 to 8 had a response speed parameter index G, as compared with the liquid crystal compositions of comparative examples 1 and 21/K33Are all smaller than the comparative examples. Therefore, when the liquid crystal compositions of examples 1 to 8 are used in a liquid crystal display device of a vertical alignment mode (e.g., VA mode, etc.), the response speed is faster.
In addition, the liquid crystal compositions of examples 1 to 8 have a response speed parameter index G, compared with the liquid crystal compositions of comparative examples 1 and 21/K11Are all smaller than the comparative examples. Therefore, when the liquid crystal compositions of examples 1 to 8 are used in a liquid crystal display device of a horizontal alignment mode (e.g., IPS mode), the response speed is higher.
Further, the liquid crystal compositions of examples 1 to 8 have K values higher than those of comparative examples 1 and 211/K33Lower values, increased light transmittance.
Further, the liquid crystal compositions of examples 1 to 8 exhibited more excellent low-temperature storage stability than those of comparative examples 1 and 2.
Further, the liquid crystal compositions of examples 9 to 14 were prepared by mixing the liquid crystal composition prepared in the above example with one of the polymerizable compounds represented by the above formulae (RM-2) and (RM-8). The formulation ratios of the liquid crystal composition and the polymerizable compound are shown in table 12.
TABLE 12 compounding ratios of polymerizable compound-containing liquid crystal compositions of examples 9 to 14
Further, Vertically Aligned (VA) liquid crystal display devices were obtained by injecting the polymerizable compound-containing liquid crystal compositions prepared in examples 9 to 14 into ITO-equipped cells each having a cell gap of 3.0 μm and coated with a polyimide alignment film causing vertical alignment, by a vacuum injection method.
The obtained VA liquid crystal display device was used with 100mW/cm while applying a rectangular wave of 10V and 100Hz2A high-pressure mercury lamp with an intensity of (365nm) was used for the exposure of 10J. Further, by performing 100J exposure in a voltage-off state, a polymer stabilized vertical alignment (PS-VA) liquid crystal display device was obtained.
The PS-VA liquid crystal display devices using the liquid crystal compositions containing the polymerizable compounds of examples 9 to 14 were measured for low-temperature storage stability and transmittance in the same manner as the VA liquid crystal display devices using the liquid crystal compositions of examples 1 to 3, and as a result, similar results were obtained.
Next, the amount of the polymerizable compound remaining in the liquid crystal display devices obtained in examples 9 to 14 was confirmed, and as a result, the remaining amount was sufficiently small. It was thus confirmed that a PS-VA liquid crystal display device in which display failure due to a change in the pretilt angle is less likely to occur.
As described above, it was confirmed that the liquid crystal composition of the present invention can achieve both high-speed response, good low-temperature storage stability, and high transmittance when used in a VA liquid crystal display device and a PS-VA display device.
Although the present invention is not exhaustive of all liquid crystal mixtures claimed, it is anticipated by those skilled in the art that other liquid crystal materials of the same type can be obtained in a similar manner without creative efforts based on the disclosed embodiments, only by combining with their own professional efforts. And are merely representative of embodiments, given the limited space available.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.