TW201307532A - Liquid crystal composition and liquid crystal display element using the same - Google Patents

Abstract

The present invention provides a liquid crystal composition and a liquid crystal display element using the same, wherein Δ n and Tni of the liquid crystal composition do not deteriorate, at least one of Δ ε and η will be approved and a dielectric anisotropy is negative. The liquid crystal composition comprises a compound selected from a group comprising at least one compound represented by formula (I) as first component and at least one compound represented by formulae (II) and (III) as second component, and at least one compound represented by formula (IV) as third component, wherein a dielectric anisotropy of which is negative.

Description

Liquid crystal composition and liquid crystal display element using the same

The present invention relates to a liquid crystal composition having a negative dielectric anisotropy (??) which is useful as a liquid crystal display material for electro-optics, and a liquid crystal display element using the liquid crystal composition.

A vertical alignment type VA-LCD using a liquid crystal composition having a negative dielectric anisotropy (negative Δ ε) is excellent in display quality because it can express black of black paint, and is widely used as a high contrast liquid crystal display device. Enter the market centered on LCD TVs. Further, in addition to the active matrix driving method represented by a liquid crystal television or the like, the use of a VA-LCD for a passive matrix driving method used as a display for a vehicle or a home appliance has recently increased. In the liquid crystal television application, in order to achieve smooth animation display performance, the gap between the glass substrates tends to be narrow, and the birefringence (Δn) of the liquid crystal material tends to increase. On the other hand, in the vehicle display, in order to obtain a good contrast for high time-division driving of a large display capacity, a liquid crystal composition having a negative Δ ε needs to be conventionally The large Δn and the absolute value of Δε are also required to be large in order to reduce the voltage.

A large number of liquid crystal compounds and liquid crystal compositions have been proposed as liquid crystal materials for VA-LCD. In order to increase Δn, it is necessary to increase the content of the liquid crystal compound having a large Δn in the liquid crystal composition, and in order to increase the absolute value of Δε, it is necessary to make the absolute value of Δε in the liquid crystal composition large. The content of the liquid crystal compound is increased. However, if the content of these compounds is increased, the viscosity (η) is deteriorated and the response speed is deteriorated.

Heretofore, a liquid crystal composition having a negative value of Δ ε and a large Δn value has been disclosed (for example, refer to Patent Documents 1 to 6). Further, a liquid crystal composition having a large positive value of Δ ε and a low value of η has also been disclosed (for example, refer to Patent Document 7).

However, there is still room for improvement in such liquid crystal compositions. In order to manufacture a liquid crystal display element having sufficient display quality, the absolute value of Δε and the magnitude of Δn are required to be large, and η or nematic phase-average A liquid crystal composition having a good balance of other physical properties such as a liquid phase transition temperature (T _ni ) (necular phase upper limit temperature).

Prior technical literature Patent literature

Patent Document 1 JP-A-2000-096058

Patent Document 2, JP-A-2001-354967

Patent Document 3 Japanese Patent Publication No. 11-140447

Patent Document 4 Japanese Patent Publication No. 11-228966

Patent Document 5 Japanese Patent Publication No. 8-104869

Patent Document 6 JP-A-2002-069449

Patent Document 7 JP-A-6-501517

An object of the present invention is to provide a liquid crystal composition and a liquid crystal display element using the liquid crystal composition, wherein at least one of Δn and T _{ni of} the liquid crystal composition is not deteriorated, and Δε absolute value and η are improved, and The dielectric anisotropy is negative.

In order to solve the above problems, the inventors of the present invention have focused their efforts on the research results, and have found that the above problems can be solved by including a liquid crystal composition having a compound having at least three specific structures.

That is, the present invention provides:

[Request 1]

A liquid crystal composition comprising, as a first component, one or two or more compounds selected from the group consisting of the compounds represented by the formula (I), and selected from the group consisting of the formulae (II) and (III) One or two or more compounds of the compound are used as the second component, and one or two or more compounds selected from the compounds represented by the formula (IV) are used as the third component;

(wherein R ¹¹ and R ¹² are independently of each other, and represent an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms, and the like. Independent of each other, unsubstituted or having at least one halogen group as a substituent, and one or two or more -CH ₂ - systems present in the groups are each independently and may be replaced by -O-, -S-, -CO-, -COO-, -OCO-, -OCO-O- as oxygen atoms are not directly bonded to each other; A ¹¹ and A ¹² are independent of each other, and are selected from (a), (b), (c) The group in the group consisting of: (a) trans-1,4-cyclohexylene (the presence of one -CH ₂ - or two or more of the adjacent ones - CH ₂ - may also be replaced by -O- and/or -S-), (b) 1,4-phenylene (the presence of one of the radicals -CH= or two or more non-adjacent -CH) = group can also be replaced by -N=), (c) 1,4-cyclohexene, 1,4-bicyclo (2.2.2) octyl, piperidine-1,4-diyl, naphthalene- 2,6-diyl, decahydronaphthalene-2,6-diyl and 1,2,3,4-tetrahydronaphthalene-2,6-diyl; the above-mentioned groups (a), (b) and (c) The hydrogen atom is independent of each other, and may be substituted with an alkyl group having 1 to 3 carbon atoms, an alkenyl group having 2 to 3 carbon atoms, and 1 to 3 carbon atoms. Alkoxy carbon atoms, an alkenyl group of 1 to 3, CN or halogen; Z ¹¹ and Z ¹² lines each independently represent -COO -, - OCO -, - CH 2 O -, - OCH 2 -, - CF ₂ O-, -OCF ₂ -, -CH ₂ CH ₂ -, -CH=CH-, -C≡C-, -(CH ₂ ) ₄ -, -CH=CH-CH ₂ CH ₂ -, -CH ₂ CH ₂ -CH=CH- or a single bond; a ¹¹ and a ¹² are independent of each other to represent 0 or 1)

(wherein R ²¹ , R ²² , R ³¹ and R ³² are independent of each other, and represent an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms. The groups are independent of each other, are unsubstituted, or have at least one halogen group as a substituent, and one or two or more -CH ₂ - systems present in the groups are independent, and Replaced with -O-, -S-, -CO-, -COO-, -OCO-, -OCO-O- as oxygen atoms are not directly bonded to each other; A ²¹ , A ²² , A ²³ , A ³¹ , A ³² and A ³³ are independent of each other and represent a group selected from the group consisting of (a), (b), and (c): (a) trans-1,4-cyclohexylene (the presence of the group) One of the -CH ₂ - or two or more non-adjacent -CH ₂ - may also be replaced by -O- and/or -S-), (b) 1,4-phenylene (the presence of the group) One of -CH= or two or more non-adjacent-CH= groups may also be replaced by -N=), (c) 1,4-cyclohexene, 1,4-bicyclo (2.2. 2) octyl, piperidine-1,4-diyl, naphthalene-2,6-diyl, decahydronaphthalene-2,6-diyl and 1,2,3,4-tetrahydronaphthalene-2, 6-diyl; the hydrogen atoms on the above (a), (b) and (c) groups are independent of each other and can be substituted with an alkyl group having 1 to 3 carbon atoms. Carbon atoms, an alkenyl group of 2 to 3 carbon atoms, an alkoxy group of 1 to 3 carbon atoms, an alkenyl group of 1 to 3, CN or ^{halogen; Z 21, Z 22, Z} 23, Z 31, Z ³² and Z ³³ are independent of each other, and represent -COO-, -OCO-, -CH ₂ O-, -OCH ₂ -, -CF ₂ O-, -OCF ₂ -, -CH ₂ CH ₂ -, -CH=CH -, -C≡C-, -(CH ₂ ) ₄ -, -CH=CH-CH ₂ CH ₂ -, -CH ₂ CH ₂ -CH=CH- or a single bond; a ²¹ , a ²² , a ³¹ and a ³² series independently of each other represents 0 or 1, when a ²² is 0, A ^{22 is} not 1,4-phenylene and Z ^{22 is} not a single bond)

(wherein R ⁴¹ and R ⁴² are independently of each other, and represent an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms; Independent of each other, being unsubstituted or having at least one halogen group as a substituent, and one or two or more -CH ₂ - systems present in the groups are each independently and may be replaced by -O-, -S-, -CO-, -COO-, -OCO-, -OCO-O- as oxygen atoms are not directly bonded to each other; A ⁴¹ is selected from (a), (b), (c) The group in the group consisting of: (a) trans-1,4-cyclohexylene (the presence of one -CH ₂ - or two or more non-adjacent -CH ₂ - may also be replaced by -O- and/or -S-), (b) 1,4-phenylene (the presence of one -CH in the group or two or more non-adjacent -CH= groups may also be replaced by - N=), (c) 1,4-cyclohexenylene, 1,4-bicyclo (2.2.2) octyl, piperidin-1,4-diyl, naphthalene-2,6-diyl, Decalin-2,6-diyl and 1,2,3,4-tetrahydronaphthalene-2,6-diyl; hydrogen atom on the above (a), (b) and (c) groups Independent of each other, may be substituted with an alkyl group having 1 to 3 carbon atoms, an alkenyl group having 2 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, and a carbon number. 1 to 3 alkenyloxy, CN or halogen; Z ⁴¹ represents -COO-, -OCO-, -CH ₂ O-, -OCH ₂ -, -CF ₂ O-, -OCF ₂ -, -CH ₂ CH ₂ -, -CH=CH-, -C≡C-, -(CH ₂ ) ₄ -, -CH=CH-CH ₂ CH ₂ -, -CH ₂ CH ₂ -CH=CH- or a single bond; a ⁴¹ represents 0 or 1).

Furthermore, the present invention provides a liquid crystal display element characterized by using the liquid crystal composition described above.

The liquid crystal composition of the present invention has the following characteristics: at least one of the dielectric anisotropy is negative, no Δn or T _{ni is} deteriorated, and at least one of Δε absolute value and η is improved. That is, the liquid crystal composition of the present invention exhibits a liquid crystal phase excellent in response speed and liquid crystallinity.

Therefore, by using the liquid crystal composition of the present invention, a liquid crystal display element excellent in both display quality and response speed can be obtained.

[Formation for implementing the invention]

The liquid crystal composition having a negative dielectric anisotropy of the present invention (hereinafter, the liquid crystal composition of the present invention) is characterized by containing at least one compound selected from the compounds represented by the following general formula (I) as a first component, at least one compound selected from the group consisting of a compound represented by the following formula (II) as a second component, and at least one compound selected from the group consisting of the compound represented by the formula (III) as a third component . By including a combination of the compound represented by the general formula (I), the compound represented by the general formula (II), and the compound represented by the general formula (III) in the liquid crystal composition, the size of Δn can be made small. At least one of the absolute value of Δε or η can be improved without lowering T _ni . Therefore, according to the present invention, a liquid crystal composition having a larger absolute value of Δε and a smaller liquid crystal composition of η can be obtained without deteriorating the balance of the physical property values of Δn and T _ni .

Hereinafter, the components will be described first.

<Compound represented by the general formula (I)>

The liquid crystal composition of the present invention contains at least one compound selected from the group consisting of compounds represented by the following formula (I). The liquid crystal composition of the present invention may contain only one kind of the compound represented by the formula (I), or may contain two or more kinds.

In the formula (I), R ¹¹ and R ¹² are independently of each other, and represent an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms or a carbon atom. A number of 2 to 8 alkenyloxy groups. In the present invention, R ¹¹ and R ¹² are each independently, and are preferably 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 a carbon number. The alkenyloxy group of 2 to 5 is more preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms. Further, each of R ¹¹ and R ¹² may be a branched group or a linear group, and is preferably a linear group.

In the formula (I), a ¹¹ represents 0 or 1. In the liquid crystal composition of the present invention, in the case where the speed of response is further accelerated, a ^{11 is} preferably 0. On the other hand, in the case where it is emphasized that T _ni is further increased, a ^{11 is} preferably 1. Further, in the case where it is emphasized that Δn is increased, a ^{11 is} preferably also 1.

In the general formula (I), A ¹¹ and A ¹² are independent of each other, and represent any of the following four kinds of divalent groups having a 6-membered ring. Further, in the following, these four kinds of divalent groups having a six-membered ring are collectively referred to as "divalent cyclic hydrocarbon group A". When A ¹¹ is a 1,4-phenylene group, one or two or more hydrogen atom systems present on the benzene ring may be substituted by halogen. When A ¹² is a 1,4-phenylene group, one or two or more hydrogen atom systems present on the benzene ring may be substituted by halogen. In the liquid crystal composition of the present invention, A ¹¹ and A ¹² are each independently, preferably 1,4-phenylene or 1,4-cyclohexylene, and 1,4-phenylene may be 1 or 2 More than one fluorine atom is substituted. In the liquid crystal composition of the present invention, when it is important to further reduce the viscosity, it is preferred that a ¹¹ in the formula (I) is 1, and A ¹¹ is a 1,4-cyclohexylene group. Moreover, to further improve the case where attention refractive index anisotropy (△ n) a, A ¹² is preferably 1,4-phenylene.

The compound represented by the formula (I) is preferably an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, and 2 carbon atoms independently of R ¹¹ and R ¹² . An alkenyl group of ~8 or an alkenyloxy group having 2 to 8 carbon atoms, a ¹¹ is 0, and A ¹² is an unsubstituted 1,4-phenylene group substituted by one or more fluorine atoms. a compound of 4-phenylene or 1,4-cyclohexylene, and R ¹¹ and R ¹² are each independently an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, and a carbon number. 2 to 8 alkenyl or 2 to 8 alkenyloxy group, a ¹¹ is 1, A ¹¹ and A ¹² are independent of each other, and A ¹² is unsubstituted 1,4-phenylene, 1 Or a compound of 1,4-phenylene or 1,4-cyclohexylene substituted by two or more fluorine atoms. More preferably, R ¹¹ and R ¹² are each independently an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 8 carbon atoms, a ¹¹ being 0, and A ¹² being unsubstituted 1,4 a compound of a 1,4-phenylene group or a 1,4-cyclohexylene group substituted with one or two or more fluorine atoms, and R ¹¹ and R ¹² are each independently a carbon number of 1 to 8. An alkyl group or an alkoxy group having 1 to 8 carbon atoms, a ¹¹ is 1, A ¹¹ and A ¹² are independent of each other, and A ¹² is an unsubstituted 1,4-phenylene group, one or two or more. A compound of a 1,4-phenylene group or a 1,4-cyclohexylene group substituted by a fluorine atom.

More specifically, the compound represented by the formula (I) is preferably a compound represented by the following formula (I-1) to (I-3). In the general formula (I-1) ~ (I -3), R 11 represents the same meaning as the general formula ¹¹ (I), the R, R ¹² represents the same meaning as the general formula ¹² (I), the R. The liquid crystal composition of the present invention preferably contains at least one compound represented by the general formulae (I-1) to (I-3) as a first component, more preferably one or two or more compounds of the formula (I). a compound represented by -1) to (I-3).

The compound represented by the general formulae (I-1) to (I-3) is preferably an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 8 carbon atoms independently of R ¹¹ and R ¹² . Base compound. More preferably, R ¹¹ is a compound having an alkyl group having 1 to 8 carbon atoms and R ¹² is an alkoxy group having 1 to 8 carbon atoms.

The content of the first component in the liquid crystal composition of the present invention (that is, the total content of one or two or more compounds represented by the formula (I)) is preferably 2% by mass or more, more preferably 2 to 50. The mass%, more preferably 2 to 40% by mass, still more preferably 5 to 30% by mass.

<Compound represented by the general formula (II)>

The liquid crystal composition of the present invention contains at least one compound selected from the group consisting of compounds represented by the following formula (II). The liquid crystal composition of the present invention may contain only one kind of the compound represented by the formula (II), or may contain two or more kinds.

In the formula (II), R ²¹ and R ²² are independently of each other, and represent an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms or a carbon atom. A number of 2 to 8 alkenyloxy groups. In the present invention, R ²¹ and R ²² are each independently, and are preferably 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 a carbon number. The alkenyloxy group of 2 to 5 is more preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms. Further, each of R ²¹ and R ²² may be a branched group or a linear group, and is preferably a linear group.

In the general formula (II), Z ²¹ and Z ²² are independent of each other, and represent a single bond, -CH ₂ CH ₂ -, -CH=CH-, -CF=CF-, -CH ₂ O-, -OCH ₂ -, -CF ₂ O-, -OCF ₂ -, -COO- or -OCO-. In the case where Z ²¹ is plural, the numbers may be the same or different. In the liquid crystal composition of the present invention, Z ²¹ and Z ²² are independently of each other, preferably a single bond, -CH ₂ CH ₂ -, -CH ₂ O-, -OCH ₂ -, -CF ₂ O-, -OCF ₂ -, -COO- or -OCO-, more preferably a single bond, -CH ₂ CH ₂ -, -CH ₂ O- or -OCH ₂ -.

In the general formula (II), A ²¹ and A ²² each independently represent a group of any one of the above-mentioned divalent cyclic hydrocarbon group A. When A ²¹ is a 1,4-phenylene group, one or two or more hydrogen atom systems present on the benzene ring may be substituted by halogen. When A ²² is a 1,4-phenylene group, one or two or more hydrogen atom systems present on the benzene ring may be substituted by halogen. Further, when A ²¹ is plural, these may be the same or different. In the present invention, A ²¹ and A ²² are each independently, and are preferably an unsubstituted 1,4-phenylene group, a 1,4-phenylene group substituted by one or two or more fluorine atoms or 1, 4-cyclohexyl group, more preferably unsubstituted 1,4-phenylene or 1,4-cyclohexylene. In the liquid crystal composition of the present invention, in the case where the viscosity is further lowered, in the general formula (II), A ^{21 is more} preferably a 1,4-cyclohexylene group.

In the formula (II), a ²¹ represents 1, 2 or 3, and a ²² represents 0 or 1.

However, the compound represented by the formula (II) does not contain a compound represented by the following formula (III). That is, a ²² is 0, a ²¹ is 2, and Z ²¹ is a single bond, 2 A ^21, the directly bonded to the 2,3-difluoro-1,4-phenylene A ²¹ is not 1,4-phenylene.

The compound represented by the formula (II) is preferably an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, and 2 to 8 carbon atoms independently of R ²¹ and R ²² . Alkenyl or alkoxy having 2 to 8 carbon atoms, Z ²¹ and Z ²² are each independently a single bond, -CH ₂ CH ₂ -, -CH ₂ O- or -OCH ₂ -, A ²¹ and A ²² They are independently unsubstituted 1,4-phenylene or 1,4-cyclohexylene, a ²¹ is 1, 2 or 3, and a ²² is 0 or 1.

More specifically, the compound represented by the formula (II) is preferably a compound represented by the following formula (II-1) to (II-12). In the general formula (II-1) ~ (II -12), R 21 represents the formula (II) in the same meaning as R ^21, R ²² represents the same meaning as the general formula ²² (II), the R, A ²¹ represents a pass in the formula (II) A ²¹ synonymous, A ²² represents the same meaning as the general formula ²² (II), the A. The liquid crystal composition of the present invention preferably contains at least one compound represented by the formula (II-1) to (II-12) as a second component, more preferably one or more compounds of the formula (II). -1) A compound represented by ~(II-12).

As the compound represented by the general formulae (II-1) to (II-12), A ²¹ and A ²² are independent of each other, and preferably unsubstituted 1,4-phenylene group, one or two or more The fluorine atom-substituted 1,4-phenylene group or 1,4-cyclohexylene group is more preferably an unsubstituted 1,4-phenylene group or a 1,4-cyclohexylene group.

As the compound represented by the general formulae (II-1) to (II-12), R ²¹ and R ²² are each independently an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 8 carbon atoms. The compound of the group; more preferably, the compound wherein R ²¹ is an alkyl group having 1 to 8 carbon atoms and R ²² is an alkoxy group having 1 to 8 carbon atoms.

The compound represented by the formula (II-1) to (II-12) is preferably a compound represented by the following formula (II-101) to (II-152). In the general formula (II-101) ~ (II -152), R 21 represents the same meaning as the general formula (II), the R ^21, R ²² represents the same meaning as the general formula ²² (II), the R. The compound represented by the formula (II-101) to (II-152) is preferably an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 8 carbon atoms independently of R ²¹ and R ²² . More preferably, R ²¹ is a compound having an alkyl group having 1 to 8 carbon atoms and R ²² is an alkoxy group having 1 to 8 carbon atoms.

When the liquid crystal composition of the present invention contains the compound represented by the formula (II-101) as the second component, it is preferred to further contain a compound represented by the following formula (II-103) as the second component.

The content of the second component in the liquid crystal composition of the present invention (that is, the total content of one or more compounds represented by the formula (II)) is preferably 5% by mass or more, more preferably 5 to 70. The mass%, more preferably 10 to 60% by mass, still more preferably 20 to 50% by mass.

<Compound represented by the formula (III)>

The liquid crystal composition of the present invention contains at least one compound selected from the group consisting of compounds represented by the following formula (III). The liquid crystal composition of the present invention may contain only one compound represented by the compound represented by the formula (III), or may contain two or more kinds.

In the formula (III), R ³¹ and R ³² are independently of each other, and represent an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms or a carbon atom. A number of 2 to 8 alkenyloxy groups. In the present invention, R ³¹ and R ³² are each independently, and are preferably 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 a carbon number. The alkenyloxy group of 2 to 5 is more preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms. Further, each of R ³¹ and R ³² may be a branched group or a linear group, and is preferably a linear group.

In the formula (III), A ³¹ represents a group of any one of the above-mentioned divalent cyclic hydrocarbon group A. When A ³¹ is a 1,4-phenylene group, one or two or more hydrogen atom systems present on the benzene ring may be substituted by halogen. In the present invention, A ^{31 is} preferably an unsubstituted 1,4-phenylene group, a 1,4-phenylene group or a 1,4-cyclohexylene group substituted with one or two or more fluorine atoms. In the liquid crystal composition of the present invention, when the viscosity is further lowered, in the general formula (III), A ^{31 is more} preferably a 1,4-cyclohexylene group.

More specifically, the compound represented by the formula (III) is preferably a compound represented by the following formula (III-1) to (III-3). Formula (III-1) ~ (III -3) in, R ³¹ represents general formula (III), the same meaning as R ^31, R ³² represents general formula (III), the same meaning as R ^32. When the compound represented by the formula (III) is contained, the liquid crystal composition of the present invention preferably contains at least one compound represented by the formula (III-1) to (III-3), more preferably 1 The compound represented by the formula (III-1) to (III-3), or more preferably one or more compounds represented by the formula (III-1).

The compound represented by the formula (III-1) to (III-3) is preferably an alkyl group having 1 to 8 carbon atoms or an alkyl group having 1 to 8 carbon atoms independently of R ³¹ and R ³² . A compound of an oxy group. More preferably, R ³¹ is a compound having an alkyl group having 1 to 8 carbon atoms and R ³² is an alkoxy group having 1 to 8 carbon atoms.

When the compound represented by the formula (III) is contained, the content of the compound represented by the formula (III) in the liquid crystal composition of the invention is preferably 2% by mass or more.

The total amount of the first component, the content of the second component, and the content of the third component in the liquid crystal composition of the present invention is preferably 10% by mass or more, more preferably 10 to 80% by mass, still more preferably 30. ~70% by mass.

<Compound represented by the general formula (IV)>

In addition to the compounds represented by the general formulae (I) to (III), the liquid crystal composition of the present invention may further contain at least one compound selected from the compounds represented by the following general formula (IV). By further containing the compound represented by the formula (IV), a liquid crystal composition having a lower viscosity can be obtained.

In the formula (IV), R ⁴¹ and R ⁴² are independently of each other, and represent an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, an alkenyl group having 2 to 8 carbon atoms or a carbon atom. A number of 2 to 8 alkenyloxy groups. In the present invention, R ⁴¹ and R ⁴² are each independently, and are preferably 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 a carbon number. 2 to 5 alkenyloxy. Further, each of R ⁴¹ and R ⁴² may be a branched group or a linear group, and is preferably a linear group.

In the case where the compound represented by the formula (IV) is contained, at least one of the compounds represented by the formula (IV) contained in the liquid crystal composition of the invention, at least one of R ⁴¹ and R ⁴² It is preferably an alkenyl group or an alkenyloxy group.

In the general formula (IV), A ⁴¹ , A ⁴² and A ⁴³ are independent of each other, and represent any of the following 17 kinds of divalent groups having a cyclic structure. Further, in the following, the 17 kinds of divalent groups having a cyclic structure are collectively referred to as "base group A' having a bivalent ring structure". In the present invention, A ⁴¹ , A ⁴² and A ⁴³ are independent of each other, and preferably are unsubstituted 1,4-phenylene groups in the group A' having a bivalent ring structure, and one or more or more. a fluorine atom-substituted 1,4-phenylene group, a methyl substituted 1,4-phenylene group or a 1,4-cyclohexylene group, more preferably an unsubstituted 1,4-phenylene group Or 1,4-cyclohexylene.

In the general formula (IV), Z ⁴¹ and Z ⁴² are independent of each other, and represent a single bond, -CH ₂ CH ₂ -, -C≡C-, -C=NN=C-, -CH=CH-, -CF=. CF-, -CF ₂ O-, -OCF ₂ -, -COO- or -OCO-. In the present invention, Z ⁴¹ and Z ⁴² are independently of each other, preferably a single bond, -CH ₂ CH ₂ -, -C≡C-, -COO- or -OCO-, more preferably a single bond or -C≡C -.

In the formula (IV), a ⁴¹ represents 0, 1, or 2. In the present invention, a ^{41 is} preferably 0 or 1. Where a ⁴¹ is 2 and A ⁴² is present in plural, the may be the same or different. Similarly, where Z ⁴² is present in plural, the terms may be the same or different.

The compound represented by the formula (IV) is preferably an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms, and 2 to 8 carbon atoms independently of R ⁴¹ and R ⁴² . An alkenyl group or an alkenyloxy group having 2 to 8 carbon atoms, and A ⁴¹ , A ⁴² and A ⁴³ are each independently an unsubstituted 1,4-benzene extending group in a group A' having a divalent ring structure. a 1,4-phenylene group substituted by one or two or more fluorine atoms, a 1,4-phenylene group or a 1,4-cyclohexylene group substituted by one methyl group, Z ⁴¹ and Z ⁴² They are compounds which are each independently a single bond or -C≡C-, a ⁴¹ is 0 or 1. More specifically, the compounds represented by the following general formulae (IV-1) to (IV-14) are preferred. In the general formula (IV-1) ~ (IV -14), R 41 represents the formula (IV) in the same meaning as R ^41, R ⁴² represents the formula (IV) in the same meaning as R ^42.

When the compound represented by the formula (IV) is contained, the liquid crystal composition of the present invention preferably contains 1 to 10 compounds represented by the formula (IV), more preferably 2 to 8 groups. Further, it is preferred to contain at least one compound represented by the general formulae (IV-1) to (IV-14). The content of the compound represented by the formula (IV) in the liquid crystal composition of the present invention is preferably 10% by mass or more, more preferably 20% by mass or more, and particularly preferably 30% by mass or more. Further, the content of the compound is preferably 80% by mass or less, more preferably 70% by mass or less, and particularly preferably 60% by mass or less.

The liquid crystal composition of the present invention may contain, in addition to the above compounds, a general nematic liquid crystal, a smectic liquid crystal, a cholesteric liquid crystal, an antioxidant, an ultraviolet absorber, and a polymerizable monomer, without departing from the effects of the present invention. Wait. However, the liquid crystal composition of the present invention is preferably a liquid crystal compound which does not contain a partial structure in which a hetero atom such as -O-O-, -O-S-, and -S-S- is directly bonded to each other.

The polymerizable monomer which the liquid crystal composition of the present invention can contain is preferably a photopolymerizable monomer. When the photopolymerizable monomer is contained, the content of the liquid crystal composition photopolymerizable monomer of the present invention is preferably from 500 to 5,000 ppm. The photopolymerizable monomer may, for example, be a monomer having a polymerizable unsaturated double bond such as an acrylate or a methacrylate.

When the liquid crystal composition of the present invention is used for an active matrix driving liquid crystal display device, the liquid crystal composition of the present invention preferably has a T _ni of 60 to 120 ° C, and more preferably 65 ° C for the lower limit value. It is 70 °C. More preferably, it is 90 ° C, and particularly preferably 80 ° C in terms of the upper limit. The Δε at 25 ° C is preferably -2.0 to -6.0, more preferably -2.5 to -5.0, and particularly preferably -2.5 to -3.5. The Δn at 25 ° C is preferably 0.08 to 0.13, more preferably 0.09 to 0.12. . Further, in view of the thin cell gap, Δn at 25 ° C is preferably 0.10 to 0.12; in the case of thick cell gap, preferably 0.08 to 0.10. viscosity at 20 ° C (η) is preferably 10 to 30 mPa·s, more preferably 10 to 25 mPa·s, and particularly preferably 10 to 20 mPa·s.

When the liquid crystal composition of the present invention is used for a passive matrix driving liquid crystal display device, the T _ni of the liquid crystal composition of the present invention is preferably 60 to 120 ° C for the purpose of use in the live use, and is more preferably the lower limit value. 65 ° C, particularly preferably 70 ° C. More preferably, it is 90 ° C, and particularly preferably 80 ° C in terms of the upper limit. In the vehicle use or the like, the lower limit is more preferably 90 ° C, and particularly preferably 100 ° C. More preferably, it is 115 ° C, and particularly preferably 105 ° C in terms of the upper limit. Δn at 25 ° C is used for low duty driving, preferably 0.08 to 0.13, and particularly preferably 0.08 to 0.11. Further, for high load driving, it is preferably 0.13 to 0.20, particularly preferably 0.15 to 0.18. Δε at 25 °C is driven at a low load, preferably -2.0 to -7.0, and particularly preferably -2.5 to -5.5. The η at 20 ° C is preferably 10 to 40 mPa ‧ s, more preferably 10 to 30 mPa ‧ s, and particularly preferably 10 to 25 mPa ‧ s.

The T _ni , Δ ε , and Δn of the liquid crystal composition of the present invention can be appropriately adjusted to suit the liquid crystal composition by adjusting the composition ratio of each of the first component and the second component. The range of use and the like. The liquid crystal composition of the present invention preferably has a T _ni of 70 ° C to 120 ° C, a Δ ε of -1.5 to -8.0 at 25 ° C and 589 nm, and a Δn of 0.080 to 0.250 at 25 ° C and 1 kHz. By making T _ni , Δ ε , and Δ n within these ranges, it can be suitably used for various purposes.

Further, by using the liquid crystal composition of the present invention, a liquid crystal display element having a vertical alignment ability can be manufactured. For example, by using the liquid crystal composition of the present invention, a liquid crystal display element having a pretilt angle of 80 to 90 can be produced.

[Examples]

Hereinafter, the present invention will be described in more detail by way of examples, but the invention is not limited to the examples and the like. Further, in the compositions of the following examples and comparative examples, "%" means "% by mass".

The terms used in the examples are as follows.

T _ni : nematic-isotropic phase transition temperature [°C]

Δn: refractive index anisotropy (589 nm, 25 ° C)

△ ε: dielectric anisotropy (1 kHz, 25 ° C)

η: bulk flow viscosity [mPa‧s] (20 ° C)

Response speed: The liquid crystal composition was injected into a vertical alignment unit cell with a gap of 3.5 μm and a pretilt angle of 89°, and was measured by a rectangular wave of 5 V and 100 Hz.

The compounds in the examples are described using the following abbreviations.

The side chain is abbreviated as follows.

-n (number): -C _n H _2n+1 (The alkyl side chain is a number, and the representative time is R.)

-On:-OC _n H _2n+1

-ndm:-(C _n H _2n+1 -C=C-(CH ₂ ) _m-1 )

Ndm-:C _n H _2n+1 -C=C-(CH ₂ ) _m-1 -

-nOm:-(CH ₂ ) _n OC _m H _2m+1

nOm-:C _n H _2n+1 O(CH ₂ ) _m -

-Od(m)n: -O(C _n H _2n+1 -C=C-(CH ₂ ) _m-2 )

d(m)nO-:C _n H _2n+1 -C=C-(CH ₂ ) _m-2 O-

The link base is as follows.

-T-:-C≡C-

-2-:-CH ₂ CH ₂ -

-1O-:-CH ₂ -O-

-O1-:-O-CH ₂ -

The ring abbreviation is as follows.

(Examples 1 to 2 and Comparative Example 1)

A liquid crystal composition containing the composition shown in Table 1 was produced, and T _ni , Δ ε, Δn and η of the liquid crystal composition were measured. The measurement results are shown in Table 1.

In the liquid crystal compound of Example 1, the compound represented by the formula (IV) in the liquid crystal compound of Comparative Example 1 was replaced with the compound represented by the formula (I) without changing the values of Δn and T _ni . . As a result, the absolute value of Δε of the liquid crystal compound of Example 1 was apparently larger than that of the liquid crystal compound of Comparative Example 1. Further, although the η of the liquid crystal compound of Example 1 was slightly larger than that of the liquid crystal compound of Comparative Example 1, the increase was smaller than 5% of the liquid crystal composition of Comparative Example 1, and it was almost the same.

The liquid crystal compound of Example 2 maintains the absolute values of Δn, T _ni and Δε to the same extent, and replaces the compound represented by the general formula (IV) in the liquid crystal compound of Comparative Example 1 with the general formula (I). Expressed as a compound. As a result, compared with the liquid crystal compound of Comparative Example 1, the η system of the liquid crystal compound of Example 2 was sharply lowered.

In particular, in Example 1, the compound represented by the formula (IV) in the liquid crystal composition of Comparative Example 1 was replaced by 2,3-difluoro-1,4-phenylene in the formula (I). A non-polar compound of 4-phenyl group and a liquid crystal composition containing a compound represented by the formula (I). Therefore, as a result, it was found that by substituting a compound represented by the general formula (I) for a nonpolar compound, Δn can be maintained, and a liquid crystal composition having a large absolute value of Δε can be obtained.

[Industrial availability]

The liquid crystal composition of the present invention is useful for a liquid crystal display device, and is also useful for an active matrix driving liquid crystal display device and a passive matrix driving liquid crystal display device, and is particularly useful for a passive matrix driving liquid crystal display device. Further, it can be used for a liquid crystal display element for a VA mode, a PSVA mode, an IPS mode, or an ECR mode.

Claims (17)

A liquid crystal composition comprising, as a first component, one or two or more compounds selected from the group consisting of the compounds represented by the formula (I), and selected from the group consisting of the formulae (II) and (III) One or two or more compounds of the compound are used as the second component, and one or two or more compounds selected from the compounds represented by the formula (IV) are used as the third component; (wherein R ¹¹ and R ¹² are independently of each other, and represent an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms, and the like. Independent of each other, unsubstituted or having at least one halogen group as a substituent, and one or two or more -CH ₂ - systems present in the groups are each independently and may be replaced by -O-, -S-, -CO-, -COO-, -OCO-, -OCO-O- as oxygen atoms are not directly bonded to each other; A ¹¹ and A ¹² are independent of each other, and are selected from (a), (b), (c) The group in the group consisting of: (a) trans-1,4-cyclohexylene (the presence of one -CH ₂ - or two or more of the adjacent ones - CH ₂ - may also be replaced by -O- and/or -S-), (b) 1,4-phenylene (the presence of one of the radicals -CH= or two or more non-adjacent -CH) = group can also be replaced by -N=), (c) 1,4-cyclohexene, 1,4-bicyclo (2.2.2) octyl, piperidine-1,4-diyl, naphthalene- 2,6-diyl, decahydronaphthalene-2,6-diyl and 1,2,3,4-tetrahydronaphthalene-2,6-diyl; the above-mentioned base (a), base (b) and (c) The hydrogen atom is independent of each other, and may be substituted with an alkyl group having 1 to 3 carbon atoms, an alkenyl group having 2 to 3 carbon atoms, and 1 to 3 carbon atoms. Alkoxy carbon atoms, an alkenyl group of 1 to 3, CN or halogen; Z ¹¹ and Z ¹² lines each independently represent -COO -, - OCO -, - CH 2 O -, - OCH 2 -, - CF ₂ O-, -OCF ₂ -, -CH ₂ CH ₂ -, -CH=CH-, -C≡C-, -(CH ₂ ) ₄ -, -CH=CH-CH ₂ CH ₂ -, -CH ₂ CH ₂ -CH=CH- or a single bond; a ¹¹ and a ¹² are independent of each other to represent 0 or 1) (wherein R ²¹ , R ²² , R ³¹ and R ³² are independent of each other, and represent an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms. The groups are independent of each other, are unsubstituted, or have at least one halogen group as a substituent, and one or two or more -CH ₂ - systems present in the groups are independent, and Replaced with -O-, -S-, -CO-, -COO-, -OCO-, -OCO-O- as oxygen atoms are not directly bonded to each other; A ²¹ , A ²² , A ²³ , A ³¹ , A ³² and A ³³ are independent of each other and represent a group selected from the group consisting of (a), (b), and (c): (a) trans-1,4-cyclohexylene (the presence of the group) One of the -CH ₂ - or two or more non-adjacent -CH ₂ - may also be replaced by -O- and/or -S-), (b) 1,4-phenylene (the presence of the group) One of -CH= or two or more non-adjacent -CH= groups may also be replaced by -N-), (c) 1,4-cyclohexene, 1,4-bicyclo (2.2. 2) octyl, piperidine-1,4-diyl, naphthalene-2,6-diyl, decahydronaphthalene-2,6-diyl and 1,2,3,4-tetrahydronaphthalene-2, 6-diyl; the hydrogen atoms on the above (a), (b) and (c) groups are independent of each other and can be substituted with an alkyl group having 1 to 3 carbon atoms. Carbon atoms, an alkenyl group of 2 to 3 carbon atoms, an alkoxy group of 1 to 3 carbon atoms, an alkenyl group of 1 to 3, CN or ^{halogen; Z 21, Z 22, Z} 23, Z 31, Z ³² and Z ³³ are independent of each other, and represent -COO-, -OCO-, -CH ₂ O-, -OCH ₂ -, -CF ₂ O-, -OCF ₂ -, -CH ₂ CH ₂ -, -CH=CH -, -C≡C-, -(CH ₂ ) ₄ -, -CH-CH-CH ₂ CH ₂ -, -CH ₂ CH ₂ -CH=CH- or a single bond; a ²¹ , a ²² , a ³¹ and a ³² series independently of each other represents 0 or 1, when a ²² is 0, A ^{22 is} not 1,4-phenylene and Z ^{22 is} not a single bond) (wherein R ⁴¹ and R ⁴² are independently of each other, and represent an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms; Independent of each other, being unsubstituted or having at least one halogen group as a substituent, and one or two or more -CH ₂ - systems present in the groups are each independently and may be replaced by -O-, -S-, -CO-, -COO-, -OCO-, -OCO-O- as oxygen atoms are not directly bonded to each other; A ⁴¹ is selected from (a), (b), (c) The group in the group consisting of: (a) trans-1,4-cyclohexylene (the presence of one -CH ₂ - or two or more non-adjacent -CH ₂ - may also be replaced by -O- and/or -S-), (b) 1,4-phenylene (the presence of one -CH in the group or two or more non-adjacent -CH= groups may also be replaced by - N=), (c) 1,4-cyclohexenylene, 1,4-bicyclo (2.2.2) octyl, piperidin-1,4-diyl, naphthalene-2,6-diyl, Decalin-2,6-diyl and 1,2,3,4-tetrahydronaphthalene-2,6-diyl; hydrogen atom on the above (a), (b) and (c) groups Independent of each other, may be substituted with an alkyl group having 1 to 3 carbon atoms, an alkenyl group having 2 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, or a carbon atom. An alkenyl group of 1 to 3, CN or halogen; Z ⁴¹ represents -COO -, - OCO -, - CH 2 O -, - OCH 2 -, - CF 2 O -, - OCF 2 -, - CH 2 CH 2 -, -CH=CH-, -C≡C-, -(CH ₂ ) ₄ -, -CH=CH-CH ₂ CH ₂ -, -CH ₂ CH ₂ -CH=CH- or a single bond; a ⁴¹ represents 0 or 1). The liquid crystal composition of claim 1, which comprises, as a fourth component, one or more compounds selected from the group consisting of compounds represented by the formula (V); (wherein R ⁵¹ and R ⁵² are independent of each other, and represent an alkyl group having 1 to 8 carbon atoms, an alkoxy group having 1 to 8 carbon atoms or an alkenyl group having 2 to 8 carbon atoms; Independent of each other, being unsubstituted or having at least one halogen group as a substituent, and one or two or more -CH ₂ - systems present in the groups are each independently and may be replaced by -O-, -S-, -CO-, -COO-, -OCO-, -OCO-O- as oxygen atoms are not directly bonded to each other; A ⁵¹ , A ⁵² and A ⁵³ are independent of each other, and are selected from The group in the group consisting of a), (b), and (c): trans-1,4-cyclohexylene (the presence of one -CH ₂ - or two or more of the adjacent ones - CH ₂ - may also be replaced by -O- and/or -S-), (b) 1,4-phenylene (the presence of one of the radicals -CH= or two or more non-adjacent -CH) = group can also be replaced by -N=), (c) 1,4-cyclohexene, 1,4-bicyclo (2.2.2) octyl, piperidine-1,4-diyl, naphthalene- 2,6-diyl, decahydronaphthalene-2,6-diyl and 1,2,3,4-tetrahydronaphthalene-2,6-diyl; the above-mentioned groups (a), (b) and The hydrogen atom in (c) is independent of each other, and may be substituted with an alkyl group having 1 to 3 carbon atoms, an alkenyl group having 2 to 3 carbon atoms, or a carbon atom. The alkoxy group having 1 to 3 carbon atoms, an alkenyl group of 1 to 3, CN or halo, but A ^51, A ⁵² and A ⁵³ does not represent a 2,3-dihalo-1,4-phenylene; Z ⁵¹ and Z ⁵² are independent of each other, and represent -COO-, -OCO-, -CH ₂ O-, -OCH ₂ -, -CF ₂ O-, -OCF ₂ -, -CH ₂ CH ₂ -, -CH=NN =CH-, -CH=CH-, -C≡C-, -(CH ₂ ) ₄ -, -CH=CH-CH ₂ CH ₂ -, -CH ₂ CH ₂ -CH=CH- or a single bond; a ⁵¹ represents 0, 1 or 2, when a ⁵¹ represents 2, the two A ⁵² systems present may be the same or different, and when a ⁵¹ represents 2, the two Z ⁵² systems present may be the same or different) . The liquid crystal composition of claim 1 or 2, which contains one or more compounds selected from the group consisting of the compounds represented by the formula (II) as a second component. The liquid crystal composition of claim 1 or 2, which contains one or more compounds selected from the group consisting of the compounds represented by the formula (III) as a second component. The liquid crystal composition according to any one of claims 1 to 4, which comprises, as a second component, one or more compounds selected from the group consisting of compounds represented by the formula (II), wherein Z ²² is -CH ₂ O- or -CF ₂ O-. The liquid crystal composition according to any one of claims 1 to 5, which comprises, as a second component, one or more compounds selected from the group consisting of compounds represented by the formula (III), wherein Z ³² is -CH ₂ O- or -CF ₂ O-. The liquid crystal composition according to any one of claims 1 to 6, which comprises, as a second component, one or more compounds selected from the group consisting of compounds represented by the formula (II), wherein A ²² is trans - 1,4-cyclohexylene, Z ²² is a single bond. The liquid crystal composition according to any one of claims 2 to 7, which contains one or more compounds as a fourth component, wherein a ⁵¹ is 1, and A ⁵¹ , A ⁵² and A ⁵³ are 1,4- The phenyl group is extended, and Z ⁵¹ and Z ⁵² are single bonds. The liquid crystal composition according to any one of claims 2 to 8, which contains one or more compounds as a fourth component, wherein a ⁵¹ is 0, and A ⁵¹ and A ⁵³ are trans-1,4- The cyclohexyl group is extended and Z ⁵¹ is a single bond. The liquid crystal composition according to any one of claims 2 to 9, which contains one or more compounds as a fourth component, wherein Z ⁵¹ is -CH=NN=CH-. The liquid crystal composition according to any one of claims 1 to 10, wherein the total amount of the first component, the second component, and the third component is from 10% by mass to 80% by mass. The liquid crystal composition according to any one of claims 1 to 11, wherein the nematic phase transition temperature is 70 ° C to 120 ° C, the dielectric anisotropy is -1.5 to -8.0, and the birefringence is 0.080. 0.250. The liquid crystal composition according to any one of claims 1 to 12, which contains 500 to 5000 ppm of a photopolymerizable monomer. A liquid crystal display element using the liquid crystal composition according to any one of claims 1 to 13. The liquid crystal display element of claim 14, wherein the pretilt angle is 80. To 90°. The liquid crystal display element of claim 14 or 15, which is of the active matrix drive type. The liquid crystal display element of claim 14 or 15, which is of a passive matrix drive type.