JP4834954B2 - Nematic liquid crystal composition and liquid crystal display device using the same - Google Patents

Description

  The present invention relates to a nematic liquid crystal composition having negative physical anisotropy having various physical properties optimal for a liquid crystal display element, and a liquid crystal display element using the same.

Currently used TN (Twisted Nematic) type liquid crystal display elements and STN (Super Twisted Nematic) type liquid crystal display elements have the problem of poor viewing angle characteristics due to changes in electro-optic characteristics depending on the viewing angle. This is a big problem in applications where viewing angle characteristics are important, such as TV. As a method for obtaining a wider viewing angle, a VA (Vertically aligned) method (see Non-Patent Document 1), an IPS (In-Plane Switching) method (see Non-Patent Document 2), and the like have been proposed and put into practical use. Unlike the TN and STN types, the liquid crystal material used in VA-LCD (Vertically Aligned Liquid Crystal Display) requires a liquid crystal material having negative dielectric anisotropy (see Patent Document 1), and has the following characteristics: Is required. 1. 1. Fast response speed 2. high nematic phase-isotropic liquid phase transition temperature (T _NI ); There is a demand for a more stable display over a wider temperature range with a response as fast as possible to a low drive voltage, that is, a desired drive voltage. In addition, it is important to make the capacitance of the TFT element smaller when the liquid crystal is driven. When the driving voltage is the same, negative dielectric anisotropy with a smaller absolute value or steep electrical There is a need for liquid crystals that exhibit optical properties. Further, there is a need for a liquid crystal composition capable of being driven at a low voltage, having a higher nematic phase-isotropic liquid phase transition temperature (T _NI ) and lower viscosity.

  In response to the above requirements, liquid crystal materials having the following 2,3-difluorophenyl groups (see Patent Documents 2 to 7) are used.

(In the formula, R and R ′ represent an alkyl group or an alkoxy group.)
However, the compound represented by the general formula (a) has a negative dielectric anisotropy having a large absolute value, but a liquid crystal composition using a large amount of this compound has a nematic phase-isotropic liquid phase transition temperature ( There is a problem of lowering (T _NI ). Moreover, although the liquid crystal composition using the compound represented by the general formula (b) has a relatively high nematic phase-isotropic liquid phase transition temperature (T _NI ), the absolute value of negative dielectric anisotropy There was a problem that was not large.

On the other hand, a liquid crystal compound having a 1,7,8-trifluoronaphthalene-2,6-diyl group is already known (see Patent Document 8) and applied to a nematic liquid crystal composition having a negative dielectric anisotropy. (See Patent Documents 9 and 10). However, in a liquid crystal composition using a compound having a 1,7,8-trifluoronaphthalene-2,6-diyl group, which compound can be used to configure the composition to achieve the above-mentioned problem? There is no specific description of the compound, and the compound itself has the characteristic that the negative dielectric anisotropy has a large absolute value and the nematic phase-isotropic liquid phase transition temperature (T _NI ) is also high. However, there is a problem that the response speed of the liquid crystal display element having a relatively high viscosity does not increase.

As described above, it is not always easy to provide a liquid crystal composition having a large absolute value of negative dielectric anisotropy, a high nematic phase-isotropic liquid phase transition temperature (T _NI ), and a low viscosity, Development of a liquid crystal composition having excellent characteristics has been desired.

JP 11-242225 A (1 page) JP-A-8-104869 (page 2) Japanese Patent Laid-Open No. 10-176167 (2 pages) JP 11-14447 A (page 2) JP 2001-192657 A (2 pages) JP 2001-316669 A (page 2) JP 2002-201447 A (2 pages) German Patent Application Publication No. 19522195 (page 2) JP 2001-40354 A (page 2) JP 2002-69449 A (2 pages) Omuro et al., Information Display Society (SID) digest, Information Display Society (SID), 1997, p845-848. Ota et al., Asian Display Digest, Information Display Society (SID), 1995, p707-710

  An object of the present invention is to provide a nematic liquid crystal composition having a negative dielectric anisotropy having a large absolute value capable of being driven at a low voltage, a wide liquid crystal temperature range, a low viscosity, and a negative dielectric anisotropy. An object of the present invention is to provide a liquid crystal display element using an object.

  In order to solve the above problems, the present invention contains at least one compound selected from the group of compounds represented by general formula (IA) and general formula (IB), and the content thereof is 10 to 70% by mass. Yes, containing at least one compound selected from the group of compounds represented by formula (IIA), formula (IIB), formula (IIC) and formula (IID), the content of which is 10 to 70 The content of the compound represented by general formula (IA), general formula (IB), general formula (IIA), general formula (IIB), general formula (IIC) and general formula (IID) 35 to 80% by mass, further containing 20 to 65% by mass of the compound represented by the general formula (III)

Wherein R ¹ to R ¹⁴ are each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an alkenyloxy group having 2 to 10 carbon atoms. Wherein one or more CH ₂ groups present in the alkyl group, the alkoxy group, the alkenyl group or the alkenyloxy group are such that the O atoms are not directly bonded to each other, —O—, Optionally substituted with -CO- or -COO-
Z ¹ to Z ⁶ and Z ⁹ to Z ¹¹ are each independently a single bond, —CH ₂ CH ₂ —, —CH═CH—, —CH ₂ CH ₂ CH ₂ CH ₂ —, —CH ₂ CH ₂ CH ₂ O-, -OCH ₂ CH ₂ CH _2- , -CH = CHCH ₂ CH _2- , -CH ₂ CH ₂ CH = CH-, -C≡C-, -CH ₂ O-, -OCH _2- , -CF ₂ represents O-, -COO- or -OCO-
Z ⁷ and Z ⁸ are each independently a single bond, —CH ₂ CH ₂ —, —CH═CH—, —CH ₂ CH ₂ CH ₂ CH ₂ —, —CH ₂ CH ₂ CH ₂ O—, —OCH ₂ CH ₂ CH _2- , -CH = CHCH ₂ CH _2- , -CH ₂ CH ₂ CH = CH-, -C≡C-, -CH ₂ O- or -OCH _2-
l and m represent 0 or 1,
A represents a trans-1,4-cyclohexylene group or a 1,4-phenylene group,
B, C and D each independently represent a trans-1,4-cyclohexylene group, a 1,4-phenylene group or a trans-1,4-cyclohexenylene group. ) Dielectric anisotropy is in the range of −12 to −3, nematic phase-isotropic liquid phase transition temperature (T _NI ) is in the range of 80 ° C. to 120 ° C., and the viscosity is 45 mPa · s or less. A nematic liquid crystal composition and a liquid crystal display device using the liquid crystal composition are provided.

  Since the liquid crystal composition of the present invention has a negative dielectric anisotropy with a large absolute value, a wide liquid crystal temperature range and a low viscosity, a display device using the liquid crystal composition has a fast response speed and can be applied at a low voltage. Since it can be driven, it is useful for a liquid crystal display element that requires a liquid crystal composition having a negative dielectric anisotropy.

  The nematic liquid crystal composition obtained by the present invention has characteristics characterized by negative dielectric anisotropy having a large absolute value, a wide liquid crystal temperature range, and a low viscosity. Further, it has characteristics characterized by an excellent voltage holding ratio and excellent chemical / physical stability with respect to a desired driving voltage. Furthermore, since the steepness is excellent, low-voltage driving is possible.

In the compounds represented by general formula (IA) and general formula (IB), R ¹ to R ⁴ preferably each independently represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms. As the alkenyl group, a vinyl group, a 1-propenyl group, and a 3-butenyl group are particularly preferable. R ¹⁵ preferably represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms.

Z ¹ to Z ² each independently represents a single bond, —CH ₂ CH ₂ —, —CH═CH— or —C≡C—, preferably represents a single bond or —CH ₂ CH ₂ —. More preferred.

  Specifically, the compounds represented by general formula (IA) and general formula (IB) are represented by the following general formula (IA-1) to general formula (IA-4) and general formula (IB-1) to general formula ( It is preferable to represent the compound represented by IB-4).

(Wherein R ¹ represents the same meaning as described in formula (IA), R ³ represents the same meaning as described in formula (IB), and R ¹⁵ represents an alkyl group having 1 to 10 carbon atoms or a carbon number. Represents 2 to 10 alkenyl groups.)
Compounds represented by general formula (IA-1) to general formula (IA-4) and general formula (IB-1) to general formula (IB-4) have a large negative dielectric anisotropy and a high absolute value. General formula (IA-) which has a nematic phase-isotropic liquid phase transition temperature (T _NI ) but has a negative dielectric anisotropy with a very large absolute value, particularly when low voltage driving is required. 2) A compound represented by formula (IA-4), formula (IB-2) or formula (IB-4) is preferred.

In the compounds represented by general formula (IA-1) to general formula (IA-4) and general formula (IB-1) to general formula (IB-4), R ¹ and R ^{3 each} have 1 to 5 carbon atoms. It is preferably an alkyl group or an alkenyl group having 2 to 5 carbon atoms, and the alkenyl group is particularly preferably a vinyl group, a 1-propenyl group or a 3-butenyl group. R ¹⁵ preferably represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms. As the alkenyl group, a vinyl group, a 1-propenyl group, and a 3-butenyl group are particularly preferable.

In the compounds represented by general formula (IIA) and general formula (IIB), R ⁵ to R ⁸ preferably each independently represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms. As the alkenyl group, a vinyl group, a 1-propenyl group, and a 3-butenyl group are particularly preferable.

Z ³ to Z ⁶ each independently represents a single bond, —CH ₂ CH ₂ —, —CH═CH— or —C≡C—, preferably a single bond, —CH ₂ CH ₂ — or —CH ₂ More preferably it represents CH ₂ —.

  Specifically, the compounds represented by general formula (IIA) and general formula (IIB) are represented by the following general formula (IIA-1) to general formula (IIA-6) and general formula (IIB-1) to general formula ( It is preferable to represent the compound represented by IIB-6).

(Wherein R ⁵ represents the same meaning as described in formula (IIA), R ⁷ represents the same meaning as described in formula (IIB), and R ¹⁵ represents an alkyl group having 1 to 10 carbon atoms or a carbon number. Represents 2 to 10 alkenyl groups.)
Compounds represented by general formula (IIA-1) to general formula (IIA-6) and general formula (IIB-1) to general formula (IIB-6) have a large negative dielectric anisotropy and high absolute value. General formula (IIA-) having a nematic phase-isotropic liquid phase transition temperature (T _NI ) but a negative dielectric anisotropy with a very large absolute value, particularly when low voltage driving is required. 2) A compound represented by general formula (IIA-4), general formula (IIA-6), general formula (IIB-2), general formula (IIB-4) or general formula (IIB-6) is preferred.

The compounds represented by general formula (IIA-1) to general formula (IIA-6) and general formula (IIB-1) to general formula (IIB-6) are nematic phase to isotropic liquid phase transition temperature (T _NI ) Can be used by adding a small amount of 0.1 to 5% by mass.

In the compounds represented by general formula (IIA-1) to general formula (IIA-6) and general formula (IIB-1) to general formula (IIB-6), R ⁵ and R ⁷ have 1 to 5 carbon atoms. It is preferably an alkyl group or an alkenyl group having 2 to 5 carbon atoms, and the alkenyl group is particularly preferably a vinyl group, a 1-propenyl group or a 3-butenyl group. R ¹⁵ preferably represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms. As the alkenyl group, a vinyl group, a 1-propenyl group, and a 3-butenyl group are particularly preferable.

In the compound represented by the general formula (IIC), it is preferable that R ⁹ to R ¹⁰ each independently represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms. The group, 1-propenyl group and 3-butenyl group are particularly preferred.

Z ⁷ to Z ⁸ each independently represents a single bond, —CH ₂ CH ₂ —, —CH═CH— or —C≡C—, preferably a single bond, —CH ₂ CH ₂ — or —CH ₂ More preferably it represents CH ₂ —.

  Specifically, the compound represented by the general formula (IIC) is preferably a compound represented by the following general formula (IIC-1) to general formula (IIC-10).

(Wherein R ⁹ represents the same meaning as described in formula (IIC), and R ¹⁵ represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms.)
Among the compounds represented by general formula (IIC-1) to general formula (IIC-10), general formula (IIC-1), general formula (IIC-2), general formula (IIC-4), general formula ( The compound represented by IIC-5), general formula (IIC-6) or general formula (IIC-8) is preferable in terms of low driving voltage and fast response speed.

In the compounds represented by the general formulas (IIC-1) to (IIC-10), R ⁹ preferably represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms. Is particularly preferably a vinyl group, a 1-propenyl group, or a 3-butenyl group. R ¹⁵ preferably represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms. As the alkenyl group, a vinyl group, a 1-propenyl group, and a 3-butenyl group are particularly preferable.

In the compound represented by the general formula (IID), each of R ¹¹ to R ¹² preferably independently represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms. A vinyl group, 1-propenyl group and 3-butenyl group are particularly preferred.

Z ⁹ preferably represents a single bond, —CH ₂ CH ₂ —, —CH═CH— or —C≡C—, and may represent a single bond, —CH ₂ CH ₂ — or —CH ₂ CH ₂ —. More preferred.

  Specifically, the compound represented by the general formula (IID) is preferably a compound represented by the following general formula (IID-1) to general formula (IID-3).

(Wherein R ¹¹ represents the same meaning as described in formula (IID), and R ¹⁵ represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms.)
The compounds represented by general formula (IID-1) to general formula (IID-3) are preferably added in a relatively small amount because of their characteristics, preferably 0.1 to 15% by mass, and 5 to 10% by mass. It is particularly preferable to add%.

In the compound represented by the general formula (III), R ¹³ to R ¹⁴ preferably each independently represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms. The group, 1-propenyl group and 3-butenyl group are particularly preferred.

Z ¹⁰ to Z ¹¹ each independently represents a single bond, —CH ₂ CH ₂ —, —CH═CH— or —C≡C—, preferably a single bond, —CH ₂ CH ₂ — or —CH ₂ More preferably it represents CH ₂ —.

  Specifically, the compound represented by the general formula (IIC) is preferably a compound represented by the following general formula (III-1) to general formula (III-22).

(In the formula, R ¹³ and R ¹⁴ each independently represent the same meaning as described in formula (III).)
The compounds represented by the general formulas (III-1) to (III-22) have a particularly low viscosity and are effective for improving the high-speed response. Among them, the general formula (III-1), the general formula ( III-2), general formula (III-3), general formula (III-4), general formula (III-7), general formula (III-11), general formula (III-12), general formula (III- 13), a compound represented by formula (III-14), formula (III-15), formula (III-19), formula (III-20) or formula (III-21) is preferred, General formula (III-1), general formula (III-2), general formula (III-4), general formula (III-7), general formula (III-11), general formula (III-12), general formula A compound represented by (III-13), general formula (III-15), general formula (III-19), general formula (III-20) or general formula (III-21) is more preferred.

  (1) The content of the compounds represented by general formula (IA) and general formula (IB) is preferably 10 to 40% by mass, more preferably 15 to 40% by mass. The content of the compound represented by the general formula (IIC) is preferably 10 to 40% by mass, and more preferably 15 to 40% by mass. The total content of the compounds represented by general formula (IA), general formula (IB) and general formula (IIC) is preferably 45 to 70% by mass, more preferably 50 to 70% by mass.

More specifically, the content of the compound represented by the general formula (IA) and the general formula (IB) is 10 to 40% by mass, and the content of the compound represented by the general formula (IIC) is 10 to 40%. A compound represented by General Formula (IA), General Formula (IB), and General Formula (IIC) in an amount of 45 to 70% by mass, and further represented by General Formula (III) The content of is preferably 30 to 55% by mass, the content of the compounds represented by the general formula (IA) and the general formula (IB) is 15 to 40% by mass, and represented by the general formula (IIC) The content of the compound represented by the general formula (IA), the general formula (IB) and the general formula (IIC) is 50 to 70% by mass, The content of the compound represented by the general formula (III) is more preferably 30 to 55% by mass. In this case, the dielectric anisotropy is preferably in the range of −6 to −3, the nematic phase-isotropic liquid phase transition temperature (T _N-I ) is preferably in the range of 80 ° C. to 120 ° C., and the refractive index anisotropy. Is preferably in the range of 0.07 to 0.15, and the viscosity is preferably 30 mPa · s or less.

Further, the dielectric anisotropy is more preferably in the range of −6 to −4, the nematic phase-isotropic liquid phase transition temperature (T _N-I ) is more preferably in the range of 90 ° C. to 120 ° C., and the refractive index is different. The directionality is more preferably in the range of 0.07 to 0.12, particularly preferably in the range of 0.07 to 0.11.

  In the case where the response speed is important, the content of the compound represented by the general formula (IA), the general formula (IB), and the general formula (IIC) is preferably 45 to 55% by mass. In this case, the viscosity is It is preferably 26 mPa · s or less.

Furthermore, the liquid crystal composition of the present invention has good steepness and can operate at a lower driving voltage as compared with a conventional liquid crystal composition having the same dielectric anisotropy. This is because the compounds of general formulas (IA) to (IIB) are selected as the first component having a very large negative dielectric anisotropy and the compound of general formula (III) is effective as the second component. This is due to the combination.

  (2) The content of the compound represented by the general formula (IA) and the general formula (IB) is preferably 25 to 60% by mass, more preferably 30 to 60% by mass, and the general formula (IIA ) And the compound represented by the general formula (IIB) is preferably 25% by mass or less. In the general formula (IA), the general formula (IB), the general formula (IIA), and the general formula (IIB), The total content of the represented compounds is preferably 35 to 65% by mass.

  More specifically, the content of the compounds represented by the general formula (IA) and the general formula (IB) is 25 to 60% by mass, and the general formula (IA), the general formula (IB), and the general formula (IIA) And the content of the compound represented by the general formula (IIB) is 35 to 65% by mass, and the content of the compound represented by the general formula (III) is preferably 35 to 65% by mass.

In the case where low voltage driving is important, the total content of the compounds represented by the general formula (IA), the general formula (IB), the general formula (IIA) and the general formula (IIB) is 50 to 65% by mass. In this case, the dielectric anisotropy is preferably in the range of −6 to −5, and the nematic phase-isotropic liquid phase transition temperature (T _N-I ) is preferably in the range of 80 ° C. to 120 ° C. The rate anisotropy is preferably in the range of 0.07 to 0.15, and the viscosity is preferably 30 mPa · s or less.

When emphasizing the response speed, the total content of the compounds represented by general formula (IA), general formula (IB), general formula (IIA) and general formula (IIB) is preferably 35 to 50% by mass. The content of the compound represented by the general formula (III) is preferably 50 to 65% by mass. In this case, the dielectric anisotropy is preferably in the range of −5 to −3, and the nematic phase isotropic. The liquid phase transition temperature (T _N-I ) is preferably in the range of 80 ° C. to 120 ° C., the refractive index anisotropy is preferably in the range of 0.07 to 0.15, and the viscosity is preferably 25 mPa · s or less. .
(3) When the low voltage driving is particularly important, the content of the compound represented by the general formula (IA), the general formula (IB), the general formula (IIA) and the general formula (IIB) is 20 to 60% by mass. Yes, the content of the compound represented by the general formula (IIC) and the general formula (IID) is 30 to 60% by mass, the general formula (IA), the general formula (IB), the general formula (IIA), the general formula The content of the compound represented by (IIB), general formula (IIC) and general formula (IID) is preferably 70 to 80% by mass. In this case, the general formula (IA), the general formula (IB), It is preferable to contain 5 or more types of compounds represented by general formula (IIA), general formula (IIB), general formula (IIC) and general formula (IID).

  Moreover, it is preferable to contain 30 mass% or less of compounds represented by general formula (III) as an additional component.

In this case, the dielectric anisotropy is in the range of −12 to −6, the nematic phase-isotropic liquid phase transition temperature (T _N-I ) is in the range of 80 ° C. to 120 ° C., and the refractive index anisotropy is Is in the range of 0.07 to 0.15, and the viscosity is preferably 45 mPa · s or less.

Further, the dielectric anisotropy is more preferably in the range of −12 to −9, the nematic phase-isotropic liquid phase transition temperature (T _N-I ) is more preferably in the range of 90 ° C. to 120 ° C., and the refractive index is different. The directionality is more preferably in the range of 0.07 to 0.12, particularly preferably in the range of 0.07 to 0.11.

  Particularly preferred combinations that enable low-voltage driving include compounds represented by general formula (IA-2), general formula (IA-4), general formula (IB-2), and general formula (IB-4). 2 or more, more preferably 3 or more compounds selected from the group are contained in an amount of 30 to 60% by mass, more preferably 40 to 60% by mass, and the compounds represented by the general formulas (IIA-2) and (IIA-4) A content of 25% by mass or less of a compound selected from the group of compounds represented by formulas (IIA-6), (IIB-2), (IIB-4) and (IIB-6) It is because it contains.

  Furthermore, the liquid crystal composition of the present invention has good steepness and can operate at a lower driving voltage as compared with a conventional liquid crystal composition having the same dielectric anisotropy.

  The liquid crystal composition of the present invention further has a very good steepness, and can operate at a lower driving voltage as compared with a conventional liquid crystal composition having the same dielectric anisotropy. This is an effect obtained by selecting the first component compound having a very large negative dielectric anisotropy absolute value and further effectively combining the second component. The steepness (γ = Vsat / Vth) is preferably 2.2 or less, and more preferably 2.0 or less.

EXAMPLES Hereinafter, although an Example is given and this invention is further explained in full detail, this invention is not limited to these Examples. Further, “%” in the compositions of the following examples and comparative examples means “mass%”. A liquid crystal display device exhibiting VA mode display characteristics was manufactured as follows (see FIG. 1). A transparent solid electrode is provided on one opposing glass substrate, and a vertical alignment film (trade name JALS-204, manufactured by JSR) is formed on it. The transparent electrode on the other glass substrate has a transparent electrode as shown in FIG. Slits with zigzag bending patterns with a width of 10μm are provided at intervals of 50μm (see Fig. 3). A vertical alignment film (trade name JALS-204 manufactured by JSR) is formed on the slits, and both glass substrates are overlapped. LCD display cell is fabricated (cell thickness 3.5μm). A liquid crystal display device was constructed by injecting a liquid crystal composition into the cell.
In the examples, the measured characteristics are as follows.
T _NI : Nematic phase-isotropic liquid phase transition temperature (° C)
Δε: Dielectric anisotropy (25 ° C and 1kHz)
Δn: birefringence (20 ° C. and 589 nm)
η: Viscosity (mPa · s) (20 ° C)
Vth: Threshold voltage (V) (25 ° C)
γ: Steepness (25 ° C) saturation voltage (ratio of (Vsat) to Vth)
γ = Vsat / Vth
VHR: Voltage holding ratio (%) (70 ° C)
The ratio of the held voltage Vt and initial voltage Vo (5V) after 5V frame time 20msec in%.
VHR (%) = Vt / Vo × 100
A cell having a cell thickness of 6 μm and homeotropic alignment (JASR-204 manufactured by JSR Co., Ltd. was used as the alignment film) was used.
(Example 1)
The following liquid crystal composition was prepared and the characteristics were measured.

(Example 2)
The following liquid crystal composition was prepared and the characteristics were measured.

(Example 3)
The following liquid crystal composition was prepared and the characteristics were measured.

(Comparative Example 1)
As Comparative Example 1, the following liquid crystal composition was prepared and the characteristics were measured.

(Comparative Example 2)
As Comparative Example 2, the following liquid crystal composition was prepared and the characteristics were measured.

The measurement results of Examples 1, 2, and 3, and Comparative Examples 1 and 2 are shown in the following table.

Comparing Example 1 and Comparative Example 1 having substantially the same dielectric anisotropy and viscosity, it can be seen that Example 1 has a considerably high nematic phase-isotropic liquid phase transition temperature (T _NI ). Comparing Example 2 and Comparative Example 1 having substantially the same viscosity as the nematic phase-isotropic liquid phase transition temperature (T _NI ), it can be seen that Example 1 has a considerably large absolute value of dielectric anisotropy. Further, when Example 3 and Comparative Example 1 having substantially the same nematic phase-isotropic liquid phase transition temperature (T _NI ) and dielectric anisotropy are compared, it can be seen that Example 3 has a considerably low viscosity.

The liquid crystal composition of Comparative Example 1 is a composition having a fairly good balance of nematic phase-isotropic liquid phase transition temperature (T _NI ), dielectric anisotropy and viscosity, but the configurations of the present invention are all compared. Better than Example 1. Further, in the liquid crystal composition of Comparative Example 2 having a high nematic phase-isotropic liquid phase transition temperature (T _NI ), the absolute value of dielectric anisotropy is considerably small and the viscosity is greatly increased.

In addition, since the liquid crystal compositions of the examples have excellent steepness, they can be driven at a lower voltage than Comparative Example 1 and have a high voltage holding ratio, so that they are useful for an active matrix. The display element using the liquid crystal composition of Example 6 is suitable for VA-LCDs for liquid crystal televisions that require high-speed response, mobile phones that require a wide liquid crystal temperature range, and PDA applications.
(Example 4)
The following liquid crystal compositions were prepared and properties were measured.

TN-I: 100.2 ° C
Δε: -4.8
Δn: 0.091
η: 23.8 mPa · s
Vth: 1.81 V
γ: 1.91
VHR: 99.5%
Example 4 has a large absolute value of negative dielectric anisotropy, a high nematic phase-isotropic liquid phase transition temperature (T _NI ), and a low viscosity.

  In addition, since Example 4 has excellent steepness, it can be driven at a low voltage and has a high voltage holding ratio, so that it is useful for an active matrix. The display element using the liquid crystal composition of Example 1 is suitable for a VA-LCD for a liquid crystal television requiring a high-speed response, a mobile phone requiring a wide liquid crystal temperature range, and a PDA application.

(Example 5)
The following liquid crystal composition was prepared and the characteristics were measured.

T _NI : 84.8 ℃
Δε: -5.8
Δn: 0.086
η: 24.1 mPa · s
Vth: 1.69 V
γ: 1.79
VHR: 99.4%
Example 5 has a large absolute value, negative dielectric anisotropy, and low viscosity. Suitable for VA-LCD for liquid crystal televisions that require high-speed response, mobile phones that require low-voltage drive, and PDA applications. Moreover, since it has excellent steepness, it can be driven at a low voltage.

(Example 6)

T _NI : 91.0 ° C
Δε: -4.9
Δn: 0.093
η: 25.2 mPa · s
VHR: 99.6%
Example 6 has a high nematic phase-isotropic liquid phase transition temperature (T _NI ), and is suitable for VA-LCDs for mobile phones, PDAs and the like that require a wide liquid crystal temperature range.
(Example 7)

T _NI : 83.7 ℃
Δε: -4.0
Δn: 0.078
η: 20.0 mPa · s
VHR: 99.7%
Example 7 has a low viscosity and is suitable for a VA-LCD for liquid crystal television applications that require a high-speed response.
(Example 8)

T _NI : 82.6 ℃
Δε: -4.4
Δn: 0.094
η: 21.5 mPa · s
VHR: 99.5%
Example 8 has a low viscosity and is suitable for a VA-LCD for liquid crystal television applications that require a high-speed response.
(Example 9)
The following liquid crystal composition was prepared and the characteristics were measured.

T _NI : 93.7 ° C
Δε: -4.6
Δn: 0.097
η: 24.1 mPa · s
Vth: 1.92V
γ: 1.95
VHR: 99.5%
Example 9 has a high nematic phase-isotropic liquid phase transition temperature (T _NI ) and a low viscosity. Suitable for VA-LCD for liquid crystal televisions that require high-speed response, mobile phones that require a wide liquid crystal temperature range, and PDA applications.
(Example 10)
The following liquid crystal composition was prepared and the characteristics were measured.

T _NI : 106.0 ° C
Δε: -4.2
Δn: 0.099
η: 26.5 mPa · s
Vth: 2.02V
γ: 2.01
VHR: 99.4%
Example 10 has a high nematic phase-isotropic liquid phase transition temperature (T _NI ). Suitable for VA-LCD for mobile phones and PDAs that require a wide liquid crystal temperature range.
(Example 11)
The following liquid crystal composition was prepared and the characteristics were measured.

T _NI : 94.8 ℃
Δε: -4.2
Δn: 0.092
η: 20.8 mPa · s
Vth: 2.06V
γ: 1.97
VHR: 99.5%
Example 11 has a low viscosity. Suitable for VA-LCD for liquid crystal TV applications that require high-speed response.
(Example 12)
The following liquid crystal composition was prepared and the characteristics were measured.

T _NI : 100.1 ° C
Δε: -4.8
Δn: 0.091
η: 24.1 mPa · s
Vth: 1.80V
γ: 1.91
VHR: 99.4%
Example 12 has a high nematic-isotropic liquid phase transition temperature (T _NI ) and a low viscosity. Suitable for VA-LCD for liquid crystal televisions that require high-speed response, mobile phones that require a wide liquid crystal temperature range, and PDA applications.
(Example 13)
The following liquid crystal composition was prepared and the characteristics were measured.

(Comparative Example 3)
As Comparative Example 3, the following liquid crystal composition was prepared and the characteristics were measured.

(Comparative Example 4)
As Comparative Example 4, the following liquid crystal composition was prepared and the characteristics were measured.

  The measurement results of Example 13 and Comparative Examples 3 and 4 are shown in the following table.

Example 13 is a liquid crystal composition having a considerably large absolute value of dielectric anisotropy. On the other hand, Comparative Example 3 has a relatively large absolute value of dielectric anisotropy, but has a low nematic phase-isotropic liquid phase transition temperature (T _NI ), a high viscosity, and —OCF ₂ as a linking group. Since a compound having-and an ester bond is used, the voltage holding ratio is low and it is difficult to use it for an active matrix.

  In the configuration of Comparative Example 4, the absolute value of dielectric anisotropy is considerably smaller than that of the example, which is disadvantageous for low voltage driving, and the viscosity is also quite high.

Example 13 has a large negative dielectric anisotropy and a high retention rate. Suitable for VA-LCD for LCD TVs, mobile phones, PDAs, etc. that require high reliability and low voltage drive.
(Example 14)

T _NI : 98.5 ℃
Δε: -9.1
Δn: 0.115
η: 40.9 mPa · s
VHR: 99.2%
Example 14 has a high netocoustic phase-isotropic liquid phase transition temperature (T _NI ), a large absolute negative dielectric anisotropy, and a high retention rate. Suitable for VA-LCDs such as LCD TVs that require high reliability and low voltage drive, mobile phones that require a wide liquid crystal temperature range, and PDA applications.
(Example 15)

T _NI : 80.1 ℃
Δε: -7.3
Δn: 0.086
η: 27.1 mPa · s
VHR: 99.3%
Example 15 has a large negative dielectric anisotropy and a high retention rate. Suitable for VA-LCD for LCD TVs, mobile phones, PDAs, etc. that require high reliability and low voltage drive.
(Example 16)

T _NI : 103.2 ° C
Δε: -7.2
Δn: 0.091
η: 28.8 mPa · s
VHR: 99.4%
Example 16 has a high netocoustic phase-isotropic liquid phase transition temperature (T _NI ), a large negative dielectric anisotropy, and a high retention rate. Suitable for VA-LCDs such as LCD TVs that require high reliability and low voltage drive, mobile phones that require a wide liquid crystal temperature range, and PDA applications.
(Example 17)

T _NI : 89.6 ℃
Δε: -10.7
Δn: 0.116
η: 39.9mPa · s
Vth: 1.22V
γ: 1.82
VHR: 99.4%
Example 17 has a large negative dielectric anisotropy and a high retention rate. Suitable for VA-LCD for LCD TVs, mobile phones, PDAs, etc. that require high reliability and low voltage drive.

It is a figure explaining the cross section of the liquid crystal display device which shows VA mode display characteristic. It is a figure explaining the transparent electrode provided with the slit which has a zigzag bending pattern. It is a figure explaining the slit which has a zigzag bending pattern. (Unit: μm)

Explanation of symbols

1 ... Glass substrate
2 ... Transparent solid electrode
3 ... Vertical alignment film
4 ... Liquid crystal phase
5 ... Transparent electrode with slits
6 ... Zigzag slit

Claims (12)

Selected from the group of compounds represented by general formula (IA), general formula (IA-1), general formula (IA-3), general formula (IB), general formula (IB-1) and general formula (IB-3) At least one compound, the content of which is 10 to 40% by mass, and is represented by the general formula (IIC), general formula (IIC-3), general formula (IIC-7), general formula (IIC-9 ) And at least one compound selected from the group of compounds represented by formula (IIC-10), the content thereof is 10 to 40% by mass, and the formulas (IA) and (IA) -1), general formula (IA-3), general formula (IB), general formula (IB-1), general formula (IB-3) and general formula (IIC), general formula (IIC-3), general formula The content of the compound represented by (IIC-7), general formula (IIC-9) and general formula (IIC-10) is 45 to 70% by mass, and further a compound represented by general formula (III) Contains 30 to 55% by mass and has a dielectric anisotropy of -12 -3, a nematic phase-isotropic liquid phase transition temperature (T _NI ) is in the range of 80 ° C. to 120 ° C., and the viscosity is 45 mPa · s or less. .

(Wherein R ¹ to R ⁴ , R ⁹ and R ¹⁰ are each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or 2 carbon atoms) To an alkenyloxy group of 1 to 10, wherein the alkyl group, the alkoxy group, the alkenyl group or one or more CH ₂ groups present in the alkenyloxy group are such that O atoms are not directly bonded to each other As may be substituted with -O-, -CO- or -COO-,
R ¹³ and R ¹⁴ each independently represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms,
Z ¹ , Z ² , Z ¹⁰ and Z ¹¹ are each independently a single bond, —CH ₂ CH ₂ —, —CH═CH—, —CH ₂ CH ₂ CH ₂ CH ₂ —, —CH ₂ CH ₂ CH ₂ O-, -OCH ₂ CH ₂ CH _2- , -CH = CHCH ₂ CH _2- , -CH ₂ CH ₂ CH = CH-, -C≡C-, -CH ₂ O-, -OCH _2- , -CF ₂ represents O-, -COO- or -OCO-
Z ⁷ and Z ⁸ are each independently a single bond, —CH ₂ CH ₂ —, —CH═CH—, —CH ₂ CH ₂ CH ₂ CH ₂ —, —CH ₂ CH ₂ CH ₂ O—, —OCH ₂ CH ₂ CH _2- , -CH = CHCH ₂ CH _2- , -CH ₂ CH ₂ CH = CH-, -C≡C-, -CH ₂ O- or -OCH _2-
l and m represent 0 or 1,
A represents a trans-1,4-cyclohexylene group or a 1,4-phenylene group,
B, C and D each independently represent a trans-1,4-cyclohexylene group, a 1,4-phenylene group or a trans-1,4-cyclohexenylene group. )

(Wherein R ¹ represents the same meaning as described in formula (IA), R ³ represents the same meaning as described in formula (IB), and R ¹⁵ represents an alkyl group having 1 to 10 carbon atoms or a carbon number. Represents 2 to 10 alkenyl groups.)

(Wherein R ⁹ represents the same meaning as described in formula (IIC), and R ¹⁵ represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms.) Selected from the group of compounds represented by general formula (IA), general formula (IA-1), general formula (IA-3), general formula (IB), general formula (IB-1) and general formula (IB-3) At least one compound, the content of which is 25 to 60% by mass, and is represented by General Formula (IIA), General Formula (IIA-1), General Formula (IIA-3), General Formula (IIA-5 ), At least one compound selected from the group of compounds represented by formula (IIB), formula (IIB-1), formula (IIB-3) and formula (IIB-5), and General Formula (IA), General Formula (IA-1), General Formula (IA-3), General Formula (IB), General Formula (IB-1), General Formula (IB-3), General Formula (IIA), General formula (IIA-1), general formula (IIA-3), general formula (IIA-5), general formula (IIB), general formula (IIB-1), general formula (IIB-3) and general formula (IIB The content of the compound represented by -5) is 35 to 65% by mass, and the compound represented by the general formula (III) 20 to 65% by mass, dielectric anisotropy is in the range of −12 to −3, nematic phase-isotropic liquid phase transition temperature (T _NI ) is in the range of 80 ° C. to 120 ° C., viscosity Is a nematic liquid crystal composition, characterized in that it is 45 mPa · s or less.

Wherein R ¹ to R ⁸ are each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an alkenyloxy group having 2 to 10 carbon atoms. Wherein one or more CH ₂ groups present in the alkyl group, the alkoxy group, the alkenyl group or the alkenyloxy group are such that the O atoms are not directly bonded to each other, —O—, Optionally substituted with -CO- or -COO-
R ¹³ and R ¹⁴ each independently represents an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms,
Z ¹ to Z ⁶ , Z ¹⁰ and Z ¹¹ are each independently a single bond, —CH ₂ CH ₂ —, —CH═CH—, —CH ₂ CH ₂ CH ₂ CH ₂ —, —CH ₂ CH ₂ CH ₂ O-, -OCH ₂ CH ₂ CH _2- , -CH = CHCH ₂ CH _2- , -CH ₂ CH ₂ CH = CH-, -C≡C-, -CH ₂ O-, -OCH _2- , -CF ₂ represents O-, -COO- or -OCO-
m represents 0 or 1,
B, C and D each independently represent a trans-1,4-cyclohexylene group, a 1,4-phenylene group or a trans-1,4-cyclohexenylene group. )

(Wherein R ¹ represents the same meaning as described in formula (IA), R ³ represents the same meaning as described in formula (IB), and R ¹⁵ represents an alkyl group having 1 to 10 carbon atoms or a carbon number. Represents 2 to 10 alkenyl groups.)

(Wherein R ⁵ represents the same meaning as described in formula (IIA), R ⁷ represents the same meaning as described in formula (IIB), and R ¹⁵ represents an alkyl group having 1 to 10 carbon atoms or a carbon number. Represents 2 to 10 alkenyl groups.) The compound represented by general formula (IA) is a compound represented by general formula (IA-2) or general formula (IA-4), and the compound represented by general formula (IB) is represented by general formula (IB- The nematic liquid crystal composition according to claim 1 or 2, which is a compound represented by 2) or the general formula (IB-4).

(Wherein R ¹ represents the same meaning as described in formula (IA), R ³ represents the same meaning as described in formula (IB), and R ¹⁵ represents an alkyl group having 1 to 10 carbon atoms or a carbon number. Represents 2 to 10 alkenyl groups.) The compound represented by general formula (IIA) is a compound represented by general formula (IIA-2), general formula (IIA-4) or general formula (IIA-6), and represented by general formula (IIB). The nematic liquid crystal composition according to claim 2, wherein the compound is a compound represented by general formula (IIB-2), general formula (IIB-4), or general formula (IIB-6).

(Wherein R ⁵ represents the same meaning as described in general formula (IIA), R ⁷ represents the same meaning as described in general formula (IIB), and R ¹⁵ represents an alkyl group having 1 to 10 carbon atoms or a carbon number. Represents 2 to 10 alkenyl groups.) The compound represented by general formula (IIC) is general formula (IIC-1), general formula (IIC-2), general formula (IIC-4), general formula (IIC-5), or general formula (IIC-6). Or the nematic liquid crystal composition of Claim 1 which is a compound represented by general formula (IIC-8).

(Wherein R ⁹ represents the same meaning as described in formula (IIC), and R ¹⁵ represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms.) The nematic liquid crystal composition according to any one of claims 1 to 5, which contains a compound represented by the general formula (IID).

Wherein R ¹¹ and R ¹² are each independently an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, or an alkenyloxy group having 2 to 10 carbon atoms. Wherein one or more CH ₂ groups present in the alkyl group, the alkoxy group, the alkenyl group or the alkenyloxy group are such that the O atoms are not directly bonded to each other, —O—, Optionally substituted with -CO- or -COO-
Z ⁹ is a single bond, -CH ₂ CH _2- , -CH = CH-, -CH ₂ CH ₂ CH ₂ CH _2- , -CH ₂ CH ₂ CH ₂ O-, -OCH ₂ CH ₂ CH ₂ -,- CH = CHCH ₂ CH _2- , -CH ₂ CH ₂ CH = CH-, -C≡C-, -CH ₂ O-, -OCH _2- , -CF ₂ O-, -COO- or -OCO- . ) The nematic liquid crystal composition according to claim 6, wherein the compound represented by the general formula (IID) is a compound represented by the general formula (IID-1) to the general formula (IID-3).

(Wherein R ¹¹ represents the same meaning as described in formula (IID), and R ¹⁵ represents an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms.) The nematic liquid crystal composition according to claim 1, wherein the compound represented by the general formula (III) is a compound represented by the general formula (III-1) to the general formula (III-22).

(In the formula, R ¹³ and R ¹⁴ have the same meaning as described in formula (III).) The dielectric anisotropy is in the range of −6 to −3, the nematic phase-isotropic liquid phase transition temperature (T _N-I ) is in the range of 80 ° C. to 120 ° C., and the refractive index anisotropy is 0. The nematic liquid crystal composition according to claim 1, which has a viscosity in the range of 0.07 to 0.15 and a viscosity of 30 mPa · s or less. The dielectric anisotropy is in the range of −6 to −3, the nematic phase-isotropic liquid phase transition temperature (T _N-I ) is in the range of 80 ° C. to 120 ° C., and the refractive index anisotropy is 0. The nematic liquid crystal composition according to claim 2, which has a viscosity in the range of 0.07 to 0.15 and a viscosity of 30 mPa · s or less. The liquid crystal display element for active matrix displays using the nematic liquid crystal composition as described in any one of Claims 1-10. A liquid crystal display element for a VA mode, an IPS mode or an ECB mode, using the nematic liquid crystal composition according to any one of claims 1 to 10.

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