JP7755378B2 - Liquid crystal composition and liquid crystal display element - Google Patents

Description

The present invention relates to a liquid crystal composition and a liquid crystal display device using the same. More specifically, the present invention relates to a so-called n-type liquid crystal composition, which exhibits a negative dielectric anisotropy (Δε).

Liquid crystal display elements are used in a variety of devices, including watches and calculators, as well as various household electrical appliances, industrial measuring instruments, automotive panels, mobile phones, smartphones, notebook PCs, tablet PCs, and televisions. Typical liquid crystal display types include TN (twisted nematic), STN (super twisted nematic), GH (guest-host), IPS (in-plane switching), FFS (fringe field switching), OCB (optically compensated birefringence), ECB (voltage-controlled birefringence), VA (vertical alignment), CSH (color super homeotropic), and FLC (ferroelectric liquid crystal). Driving methods include static driving, multiplex driving, simple matrix driving, and active matrix (AM) driving using TFTs (thin film transistors) or TFDs (thin film diodes). Among these display modes, IPS type, FFS type, ECB type, VA type, CSH type, etc. are known to exhibit advantageous characteristics when using a liquid crystal composition that exhibits a negative dielectric anisotropy (n-type liquid crystal composition).

Display modes using n-type liquid crystal compositions include vertical alignment modes, such as VA mode and PSA (Polymer Sustained Alignment) or PSVA (Polymer Stabilized Vertical Alignment) modes, in which alignment is controlled by polymerizing a polymerizable compound in the liquid crystal phase, and horizontal alignment modes, such as IPS mode and FFS mode.

All of these drive methods require low-voltage drive, high transmittance, fast response, and a wide operating temperature range. This means a large absolute value of dielectric anisotropy (Δε), a small viscosity (η), and a high nematic-isotropic liquid phase transition temperature (Tni). Furthermore, by setting Δn×d, which is the product of refractive index anisotropy (Δn) and cell gap (d), the Δn of the liquid crystal composition must be adjusted to an appropriate range to match the cell gap.

Furthermore, IPS-type and FFS-type liquid crystal display devices, which offer high quality and excellent visual characteristics, are widely used as liquid crystal displays for smartphones and tablets. IPS-type and FFS-type liquid crystal displays are horizontal electric field modes that utilize an electric field generated horizontally relative to the substrate, and can use liquid crystal materials with a negative Δε value. Liquid crystal materials with a negative Δε value greater than -2 and with a large absolute value are known, such as liquid crystal compositions using the following compounds (A), (B), and (C) (see Patent Document 1).

In IPS mode and FFS mode, as with other driving methods, LCD display elements with high transmittance, fast response, a wide operating temperature range, good contrast, and low driving voltage are required.

Liquid crystal compositions typically used in liquid crystal layers contain a mixture of two components: a liquid crystal compound with negative dielectric anisotropy (polar component) and a liquid crystal compound with neutral dielectric anisotropy (non-polar component), and the entire liquid crystal composition contains several to several dozen types of liquid crystal compounds. Therefore, depending on the combination of liquid crystal compounds, there are cases where the mutual compatibility is poor, and some of the liquid crystal compounds contained in the liquid crystal composition precipitate, preventing the liquid crystal material from fully functioning. On the other hand, even in liquid crystal compositions where the liquid crystal compounds used are mutually compatible and do not precipitate, when liquid crystal display elements are manufactured using the liquid crystal composition, all physical properties such as transmittance, high-speed response, and visibility may not be satisfactory.

International Publication No. 2010/084823

The problem that the present invention aims to solve is to provide a liquid crystal composition that uses a combination of liquid crystal compounds with specific structures and negative dielectric anisotropy, and that has excellent storage stability and is free from precipitation of the liquid crystal compounds. The object is also to provide a liquid crystal display element that combines high transmittance, high-speed response, a wide operating temperature range, and good contrast by using this liquid crystal composition.

The inventors investigated various combinations of liquid crystal compounds and discovered that the above-mentioned problems could be solved by adjusting their selection, leading to the completion of the present invention.

That is, the present invention relates to a liquid crystal composition that contains two or more liquid crystal compounds having a specific terminal structure represented by the following general formula (N1) as liquid crystal compounds having a dielectric anisotropy more negative than -2, the total content of the liquid crystal compounds having the specific terminal structure represented by general formula (N1) being 75% by mass or more of the total content of liquid crystal compounds having a dielectric anisotropy more negative than -2 used in the liquid crystal composition, and that contains a liquid crystal compound represented by formula (L-10-1) as a liquid crystal compound with neutral dielectric anisotropy (-2<Δε<2).

The liquid crystal composition of the present invention satisfies the various properties required of an n-type liquid crystal composition with a negative Δε, while also exhibiting excellent storage stability. Furthermore, when used in liquid crystal devices, it produces liquid crystal display elements that combine high transmittance, fast response, a wide operating temperature range, and high contrast, making it useful as display elements for liquid crystal TVs, monitors, and other devices.

As described above, the present invention relates to a liquid crystal composition and a liquid crystal display device using the same. First, an embodiment of the liquid crystal composition of the present invention will be described below.
<Liquid Crystal Composition>
The liquid crystal composition of the present invention contains two or more liquid crystal compounds having a dielectric anisotropy more negative than -2. The value of the dielectric anisotropy (Δε: measured at 25°C) was calculated from the formula Δε = ε∥ - ε⊥. The dielectric constants (ε∥, ε⊥) were measured as follows.
A) Measurement of dielectric constant (ε∥): A vertical alignment film was applied to a thoroughly cleaned glass substrate and baked. Two glass substrates were arranged so that the alignment film-coated surfaces faced each other, and a spacer agent and a sealant were sandwiched between the glass substrates so that the distance (cell gap) between the glass substrates was approximately 10 μm. The sealant was then cured to obtain a vertical alignment element. A liquid crystal material was injected into the vertical alignment element and sealed with an adhesive that cures under ultraviolet light. A sine wave (0.3 V, 1 kHz) was applied to this element, and the dielectric constant (ε∥) of the liquid crystal material in the long axis direction was measured.
B) Measurement of dielectric constant (ε⊥): A horizontal alignment film was applied to a thoroughly cleaned glass substrate, baked, and then rubbed. Two glass substrates were arranged so that the alignment film-coated surfaces faced each other and the rubbing direction was 180°. A spacer agent and a sealant were sandwiched between the glass substrates so that the distance (cell gap) between the glass substrates was approximately 10 μm, and the sealant was cured to obtain an anti-parallel horizontal alignment element. A liquid crystal material was injected into the anti-parallel horizontal alignment element and sealed with a UV-curable adhesive. A sine wave (20.0 V, 1 kHz) was applied to this element, and the dielectric constant (ε⊥) of the liquid crystal material in the minor axis direction was measured.
C) For liquid crystal compounds that do not exhibit a nematic phase at 25°C, the liquid crystal compound to be measured was added at various concentrations to a base liquid crystal whose ε∥ and ε⊥ were known, and the ε∥ and ε⊥ of the liquid crystal compound alone were calculated by extrapolation.
(Compound (N1))
The liquid crystal composition of the present invention contains two or more liquid crystal compounds selected from the following general formula (N1) as liquid crystal compounds having a dielectric anisotropy more negative than −2. Hereinafter, the compound represented by general formula (N1) may be referred to as "compound (N1)." Compounds represented by other formulas may also be referred to in the same manner.

(In the formula, A ^N11 and A ^N12 each independently represent
(a) a 1,4-cyclohexylene group (one —CH ₂ — or two or more non-adjacent —CH ₂ — groups in this group may be replaced by —O—), and (b) a 1,4-phenylene group (one —CH= or two or more non-adjacent —CH= groups in this group may be replaced by —N=).
(c) a naphthalene-2,6-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, or a decahydronaphthalene-2,6-diyl group (one —CH= or two or more non-adjacent —CH= groups in the naphthalene-2,6-diyl group or the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced by —N=).
(d) a group selected from the group consisting of 1,4-cyclohexenylene groups, wherein the groups (a), (b), (c), and (d) may each independently be substituted with a cyano group, a fluorine atom, or a chlorine atom;
Z ^N11 and Z ^N12 each independently represent a single bond, —CH ₂ CH ₂ —, —(CH ₂ ) ₄ —, —OCH ₂ —, —CH ₂ O—, —COO—, —OCO—, —OCF ₂ —, —CF ₂ O—, —CH═N—N═CH—, —CH═CH—, —CF═CF— or —C≡C—;
^nN11 and ^nN12 each independently represent 0 or 1, provided that ^nN11 + ^nN12 is 1 or 2.
In general formula (N1), when n ^N11 represents 0 and n ^N12 represents 1, A ^N12 preferably represents a 1,4-cyclohexylene group, a 1,4-phenylene group, or a 1,4-cyclohexenylene group, and the group may be substituted with a cyano group, a fluorine atom, or a chlorine atom.

In general formula (N1), when n ^N11 represents 0 and n ^N12 represents 1, Z ^N12 preferably represents a single bond, —OCH ₂ —, —CH ₂ O—, —COO—, —OCO—, —CH═CH—, —CF═CF— or —C≡C—; Z ^N12 preferably represents a single bond, —OCH ₂ —, —CH ₂ O—, —COO— or —OCO—; and Z ^N12 preferably represents a single bond, —OCH ₂ — or —CH ₂ O—.

In general formula (N1), when n ^N11 represents 1 and n ^N12 represents 1, A ^N11 preferably represents a 1,4-cyclohexylene group, a 1,4-phenylene group, or a 1,4-cyclohexenylene group, and the group may be substituted with a cyano group, a fluorine atom, or a chlorine atom.

In general formula (N1), when n ^N11 represents 1 and n ^N12 represents 1, A ^N12 preferably represents a 1,4-cyclohexylene group, a 1,4-phenylene group, or a 1,4-cyclohexenylene group, and the group may be substituted with a cyano group, a fluorine atom, or a chlorine atom.

In general formula (N1), when n ^N11 represents 1 and n ^N12 represents 1, Z ^N11 preferably represents a single bond, —OCH ₂ —, —CH ₂ O—, —CH ₂ CH ₂ —, —CF═CF— or —C≡C—; Z ^N11 preferably represents a single bond, —OCH ₂ —, —CH ₂ O—, —CH ₂ CH ₂ — or —OCO—; and Z ^N11 preferably represents a single bond or —CH ₂ CH ₂ —.

In general formula (N1), when n ^N11 represents 1 and n ^N12 represents 1, Z ^N12 preferably represents a single bond, —OCH ₂ —, —CH ₂ O—, —COO—, —OCO—, —CH═CH—, —CF═CF— or —C≡C—; Z ^N12 preferably represents a single bond, —OCH ₂ —, —CH ₂ O—, —COO— or —OCO—; and Z ^N12 preferably represents a single bond, —OCH ₂ — or —CH ₂ O—.

The above-mentioned compound (N1) is a group of compounds that have a so-called mesogenic skeleton portion with negative dielectric anisotropy, as well as an alkyl group (3 carbon atoms) and an alkoxy group (2 carbon atoms) with specific numbers of carbon atoms at both terminal portions bonded to the mesogenic skeleton portion. By using multiple liquid crystal compounds with different mesogenic skeleton structures but the same number of carbon atoms at both terminal portions (an alkyl group (3 carbon atoms) and an alkoxy group (2 carbon atoms)), in a liquid crystal composition, it is possible to obtain a liquid crystal composition with excellent storage stability and no precipitation of the liquid crystal compound.

It is important that the liquid crystal composition of the present invention has a total content of the liquid crystal compounds represented by general formula (N1) of 75% by mass or more, preferably 80% by mass or more, 85% by mass or more, 90% by mass or more, 95% by mass or more, or 100% by mass of the total content of liquid crystal compounds having a dielectric anisotropy more negative than −2 used in the liquid crystal composition.
(Compound (N1-I))
The liquid crystal composition of the present invention preferably contains a liquid crystal compound represented by the following formula (N1-I) as the liquid crystal compound represented by general formula (N1) having a dielectric anisotropy more negative than −2. Hereinafter, the compound represented by formula (N1-I) may be referred to as "compound (N1-I)." The same may also be said for compounds represented by other formulas.

The above-mentioned compound (N1-I) is a compound that has a so-called mesogenic skeleton portion with negative dielectric anisotropy, as well as an alkyl group (3 carbon atoms) and an alkoxy group (2 carbon atoms) with specific numbers of carbon atoms at both terminal portions bonded to the mesogenic skeleton portion. By using a liquid crystal compound with negative dielectric anisotropy that has a different mesogenic skeleton structure from compound (N1-I) but the same numbers of carbon atoms at both terminal portions (an alkyl group (3 carbon atoms) and an alkoxy group (2 carbon atoms)), as described below, in a liquid crystal composition, a liquid crystal composition with excellent storage stability and no precipitation of the liquid crystal compound can be obtained.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content lower. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by Formula (N1-I) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 3 mass%, 5 mass%, 7 mass%, 10 mass%, or 12 mass%, and the preferred upper limit of the content is 35 mass%, 30 mass%, 28 mass%, 26 mass%, 24 mass%, 22 mass%, 21 mass%, or 20 mass%, relative to the total amount of liquid crystal compounds contained in the composition of the present invention.
(Compound (N1-II))
The liquid crystal composition of the present invention preferably contains a liquid crystal compound represented by the following formula (N1-II) as a liquid crystal compound having a dielectric anisotropy more negative than −2.

The above-mentioned compound (N1-II) is a compound that has a so-called mesogenic skeleton portion with negative dielectric anisotropy, as well as an alkyl group (3 carbon atoms) and an alkoxy group (2 carbon atoms) with specific numbers of carbon atoms at both terminal portions bonded to the mesogenic skeleton portion. By using a liquid crystal compound with negative dielectric anisotropy that has a different mesogenic skeleton structure from compound (N1-II) but the same numbers of carbon atoms at both terminal portions (an alkyl group (3 carbon atoms) and an alkoxy group (2 carbon atoms)), in a liquid crystal composition, a liquid crystal composition with excellent storage stability and no precipitation of the liquid crystal compound can be obtained.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content lower. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by Formula (N1-II) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 3 mass%, 5 mass%, 7 mass%, or 10 mass%, and the preferred upper limit of the content is 35 mass%, 30 mass%, 28 mass%, 26 mass%, 24 mass%, or 22 mass%, relative to the total amount of liquid crystal compounds contained in the composition of the present invention.
(Compound (N1-III))
The liquid crystal composition of the present invention preferably contains a liquid crystal compound represented by the following formula (N1-III) as a liquid crystal compound having a dielectric anisotropy more negative than −2.

The above-mentioned compound (N1-III) is a compound that has a so-called mesogenic skeleton portion with negative dielectric anisotropy, as well as an alkyl group (3 carbon atoms) and an alkoxy group (2 carbon atoms) with specific numbers of carbon atoms at both terminal portions bonded to the mesogenic skeleton portion. By using a liquid crystal compound with negative dielectric anisotropy that has a different mesogenic skeleton structure from compound (N1-III) but the same numbers of carbon atoms at both terminal portions (an alkyl group (3 carbon atoms) and an alkoxy group (2 carbon atoms)), in a liquid crystal composition, a liquid crystal composition with excellent storage stability and no precipitation of the liquid crystal compound can be obtained.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content lower. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by Formula (N1-III) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 3 mass%, 5 mass%, 7 mass%, or 8 mass%, and the preferred upper limit of the content is 35 mass%, 30 mass%, 28 mass%, 26 mass%, 24 mass%, 22 mass%, 21 mass%, 20 mass%, or 18 mass%, relative to the total amount of liquid crystal compounds contained in the composition of the present invention.
(Compound (N1-IV))
The liquid crystal composition of the present invention preferably contains a liquid crystal compound represented by the following formula (N1-IV) as a liquid crystal compound having a dielectric anisotropy more negative than −2.

The above-mentioned compound (N1-IV) is a compound that has a so-called mesogenic skeleton portion with negative dielectric anisotropy, as well as an alkyl group (3 carbon atoms) and an alkoxy group (2 carbon atoms) with specific numbers of carbon atoms at both terminal portions bonded to the mesogenic skeleton portion. By using a liquid crystal compound with negative dielectric anisotropy that has a different mesogenic skeleton structure from compound (N1-IV) but the same numbers of carbon atoms at both terminal portions (an alkyl group (3 carbon atoms) and an alkoxy group (2 carbon atoms)), in a liquid crystal composition, a liquid crystal composition with excellent storage stability and no precipitation of the liquid crystal compound can be obtained.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content lower. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by Formula (N1-IV) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 3 mass%, 5 mass%, 7 mass%, or 8 mass%, and the preferred upper limit of the content is 35 mass%, 30 mass%, 28 mass%, 26 mass%, 24 mass%, 22 mass%, 21 mass%, or 20 mass%, relative to the total amount of liquid crystal compounds contained in the composition of the present invention.
(Compound (N1-V))
The liquid crystal composition of the present invention preferably contains a liquid crystal compound represented by the following formula (N1-V) as a liquid crystal compound having a dielectric anisotropy more negative than −2.

The above-mentioned compound (N1-V) is a compound that has a so-called mesogenic skeleton portion with negative dielectric anisotropy, as well as an alkyl group (3 carbon atoms) and an alkoxy group (2 carbon atoms) with specific numbers of carbon atoms at both terminal portions bonded to the mesogenic skeleton portion. By using a liquid crystal compound with negative dielectric anisotropy that has a different mesogenic skeleton structure from compound (N1-V) but the same numbers of carbon atoms at both terminal portions (an alkyl group (3 carbon atoms) and an alkoxy group (2 carbon atoms)), in a liquid crystal composition, a liquid crystal composition with excellent storage stability and no precipitation of the liquid crystal compound can be obtained.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content lower. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by formula (V) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 3 mass%, 5 mass%, or 7 mass%, and the preferred upper limit of the content is 35 mass%, 30 mass%, 28 mass%, 26 mass%, 24 mass%, 22 mass%, 20 mass%, 18 mass%, or 15 mass%, relative to the total amount of liquid crystal compounds contained in the composition of the present invention.
(Compound (N1-VI))
The liquid crystal composition of the present invention preferably contains a liquid crystal compound represented by the following formula (N1-VI) as a liquid crystal compound having a dielectric anisotropy more negative than −2.

The above-mentioned compound (N1-VI) is a compound that has a so-called mesogenic skeleton portion with negative dielectric anisotropy, as well as an alkyl group (3 carbon atoms) and an alkoxy group (2 carbon atoms) with specific numbers of carbon atoms at both terminal portions bonded to the mesogenic skeleton portion. By using a liquid crystal compound with negative dielectric anisotropy that has a different mesogenic skeleton structure from compound (N1-VI) but the same numbers of carbon atoms at both terminal portions (an alkyl group (3 carbon atoms) and an alkoxy group (2 carbon atoms)), in a liquid crystal composition, a liquid crystal composition with excellent storage stability and no precipitation of the liquid crystal compound can be obtained.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content lower. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by formula (N1-VI) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 3% by mass and 5% by mass. The preferred upper limit of the content is 24% by mass, 22% by mass, 21% by mass, 20% by mass, 18% by mass, and 15% by mass relative to the total amount of liquid crystal compounds contained in the composition of the present invention.

It is important that the liquid crystal composition of the present invention contains liquid crystal compounds selected from the group consisting of the liquid crystal compound represented by formula (N1-III), the liquid crystal compound represented by formula (N1-I), the liquid crystal compound represented by formula (N1-II), the liquid crystal compound represented by formula (N1-IV), the liquid crystal compound represented by formula (N1-V), and the liquid crystal compound represented by formula (N1-VI) in a total content of 75% by mass or more, preferably 80% by mass or more, 85% by mass or more, 90% by mass or more, 95% by mass or more, or 100% by mass of the total content of liquid crystal compounds having a dielectric anisotropy more negative than −2 used in the liquid crystal composition. In particular, the liquid crystal composition of the present invention preferably contains a liquid crystal compound represented by formula (N1-III) as an essential component, as the liquid crystal compound having a dielectric anisotropy more negative than −2, and more preferably contains a liquid crystal compound represented by formula (N1-III) as an essential component, and further contains liquid crystal compounds represented by formula (N1-I) and/or formula (N1-IV) as essential components. When a liquid crystal composition having a total content of the liquid crystal compounds represented by the formulae (N1-I) to (N1-VI) within the above range is used, and further when the liquid crystal compounds represented by the formulae (N1-I) to (N1-VI) are used as essential components, a liquid crystal composition having excellent storage stability and free from precipitation of the liquid crystal compound can be obtained, and a liquid crystal display element using the liquid crystal composition can simultaneously achieve high transmittance, high-speed response, a wide operating temperature range, and good contrast.
(Other liquid crystal compounds having a dielectric anisotropy more negative than −2)
(Compound (N-1))
The liquid crystal composition of the present invention may further contain one or more compounds represented by general formula (N-1) as the liquid crystal compound having a dielectric anisotropy more negative than −2 other than the liquid crystal compound represented by general formula (N1), i.e., the liquid crystal compound represented by formula (N1-I), the liquid crystal compound represented by formula (N1-II), the liquid crystal compound represented by formula (N1-III), the liquid crystal compound represented by formula (N1-IV), the liquid crystal compound represented by formula (N1-V), and the liquid crystal compound represented by formula (N1-VI).

(In the formula, R ^N11 and R ^N12 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO— or —OCO—;
A ^N11 and A ^N12 each independently represent (a) a 1,4-cyclohexylene group (in which one —CH ₂ — or two or more non-adjacent —CH ₂ — groups may be replaced with —O—), and (b) a 1,4-phenylene group (in which one —CH= or two or more non-adjacent —CH= groups may be replaced with —N=).
(c) a naphthalene-2,6-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, or a decahydronaphthalene-2,6-diyl group (one —CH= or two or more non-adjacent —CH= groups in the naphthalene-2,6-diyl group or the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced by —N=).
(d) a group selected from the group consisting of 1,4-cyclohexenylene groups, wherein the groups (a), (b), (c), and (d) may each independently be substituted with a cyano group, a fluorine atom, or a chlorine atom;
Z ^N11 and Z ^N12 each independently represent a single bond, —CH ₂ CH ₂ —, —(CH ₂ ) ₄ —, —OCH ₂ —, —CH ₂ O—, —COO—, —OCO—, —OCF ₂ —, —CF ₂ O—, —CH═N—N═CH—, —CH═CH—, —CF═CF— or —C≡C—;
n ^N11 and n ^N12 each independently represent an integer of 0 to 3, provided that n ^N11 +n ^N12 is 1, 2, or 3, and when a plurality of A ^N11 to A ^N32 and Z ^N11 to Z ^N32 are present, they may be the same or different, excluding the compounds represented by formula (N1-I), formula (N1-II), formula (N1-III), formula (N1-IV), formula (N1-V), and formula (N1-VI).
In general formula (N-1), R ^N11 and R ^N12 each independently represent preferably an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 8 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms, still more preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 5 carbon atoms, and particularly preferably an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms.

Furthermore, if the ring structure to which it is bonded is a phenyl group (aromatic), a linear alkyl group having 1 to 5 carbon atoms or a linear alkoxy group having 1 to 4 carbon atoms is preferred; and if the ring structure to which it is bonded is a saturated ring structure such as cyclohexane, pyran, or dioxane, a linear alkyl group having 1 to 5 carbon atoms or a linear alkoxy group having 1 to 4 carbon atoms is preferred. In order to stabilize the nematic phase, it is preferable that the total number of carbon atoms and, if present, oxygen atoms is 5 or less, and a linear structure is preferred.

In general formula (N-1), A ^N11 and A ^N12 are each independently preferably aromatic when it is required to increase Δn, and are preferably aliphatic in order to improve the response speed, and preferably represent a trans-1,4-cyclohexylene group, a 1,4-phenylene group, a 2-fluoro-1,4-phenylene group, a 3-fluoro-1,4-phenylene group, a 3,5-difluoro-1,4-phenylene group, a 2,3-difluoro-1,4-phenylene group, a 1,4-cyclohexenylene group, a 1,4-bicyclo[2.2.2]octylene group, a piperidine-1,4-diyl group, a naphthalene-2,6-diyl group, a decahydronaphthalene-2,6-diyl group, or a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, and more preferably represent the following structure:

More preferably, it represents a trans-1,4-cyclohexylene group, a 1,4-cyclohexenylene group, or a 1,4-phenylene group.

In general formula (N-1), Z ^N11 and Z ^N12 each independently preferably represent —CH ₂ O—, —CF ₂ O—, —CH ₂ CH ₂ —, —CF ₂ CF ₂ — or a single bond, more preferably —CH ₂ O—, —CH ₂ CH ₂ — or a single bond, and particularly preferably —CH ₂ O— or a single bond.

In general formula (N-1), n ^N11 +n ^N12 is preferably 1 or 2, and a combination in which n ^N11 is 1 and n ^N12 is 0, a combination in which n ^N11 is 2 and n ^N12 is 0, a combination in which n ^N11 is 1 and n ^N12 is 1, or a combination in which n ^N11 is 2 and n ^N12 is 1 is preferred.

The preferred lower limit of the content of the compound represented by formula (N-1) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

When the viscosity of the composition of the present invention is to be kept low and a composition with a fast response speed is required, it is preferable that the above lower limit value be low and the above upper limit value be low. Furthermore, when the Tni of the composition of the present invention is to be kept high and a composition with good temperature stability is required, it is preferable that the above lower limit value be low and the above upper limit value be low. Furthermore, when it is desired to increase the dielectric anisotropy in order to keep the driving voltage low, it is preferable that the above lower limit value be high and the above upper limit value be high.

Specific examples of compounds having a dielectric anisotropy more negative than -2 and represented by general formula (N-1) are preferably compounds selected from the group of compounds represented by general formulas (N-1-1) to (N-1-5), (N-1-11) to (N-1-18), and (N-1-20) to (N-1-22).

The compound represented by general formula (N-1-1) is the following compound:

(In the formula, R ^N111 and R ^N112 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO—, or —OCO—, excluding the compound represented by formula (N1-II).)
R ^N111 is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a propyl group or a pentyl group. R ^N112 is preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and more preferably an ethoxy group or a butoxy group.

The compound represented by general formula (N-1-1) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content lower. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by general formula (N-1-1) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

Furthermore, the compound represented by general formula (N-1-1) is preferably a compound selected from the group of compounds represented by formulas (N-1-1.1) to (N-1-1.17), preferably a compound represented by formulas (N-1-1.1) to (N-1-1.3), and more preferably a compound represented by formulas (N-1-1.1) and (N-1-1.2).

The compounds represented by formulas (N-1-1.1) to (N-1-1.7) can be used alone or in combination, but the preferred lower limit of the content of each of these compounds alone relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

The compound represented by general formula (N-1-2) is the following compound:

(In the formula, R ^N121 and R ^N122 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO—, or —OCO—, excluding the compound represented by formula (N1-IV).)
R ^N121 is preferably an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, and is preferably an ethyl group, a propyl group, a butyl group, or a pentyl group. R ^N122 is preferably an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 4 to 5 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms, and is preferably a methyl group, a propyl group, a methoxy group, an ethoxy group, or a propoxy group.

The compound represented by general formula (N-1-2) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content lower. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by general formula (N-1-2) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

Furthermore, the compound represented by general formula (N-1-2) is preferably a compound selected from the group of compounds represented by formulas (N-1-2.1) to (N-1-2.10), and is preferably a compound represented by formulas (N-1-2.3) to (N-1-2.6), (N-1-2.7), (N-1-2.8) and (N-1-2.10). When emphasis is placed on improving Δε, the compounds represented by formulas (N-1-2.3) to (N-1-2.6) are preferred, and when emphasis is placed on improving T _NI , the compounds represented by formulas (N-1-2.7), (N-1-2.8) and (N-1-2.10) are preferred.

The compounds represented by formulas (N-1-2.1) to (N-1-2.10) can be used alone or in combination, but the preferred lower limit of the content of each of these compounds alone relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

The compound represented by general formula (N-1-3) is the following compound:

(In the formula, R ^N131 and R ^N132 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO—, or —OCO—, excluding the compound represented by formula (N1-III).)
R ^N131 is preferably an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, and is preferably an ethyl group, a propyl group, or a butyl group. R ^N132 is preferably an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 4 to 5 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms, and is preferably an ethoxy group, a propoxy group, or a butoxy group.

The compound represented by general formula (N-1-3) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content lower. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by general formula (N-1-3) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

Furthermore, the compound represented by general formula (N-1-3) is preferably a compound selected from the group of compounds represented by formulas (N-1-3.1) to (N-1-3.8), preferably a compound represented by formulas (N-1-3.1) to (N-1-3.6), and more preferably a compound represented by formulas (N-1-3.1), (N-1-3.2), (N-1-3.3), and (N-1-3.5).

The compounds represented by formulas (N-1-3.1) to (N-1-3.8) can be used alone or in combination. However, formula (N-1-3.1) is preferably used alone, or a combination of two or three compounds selected from formulas (N-1-3.2), (N-1-3.3), and (N-1-3.5). The preferred lower limits of the content of a single compound or these compounds relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention are 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, and 2.5 mass%. The preferred upper limits of the content are 6.5 mass%, 6 mass%, 5.5 mass%, and 5 mass%.

The compound represented by general formula (N-1-4) is the following compound:

(In the formula, R ^N141 and R ^N142 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO— or —OCO—.)
In general formula (N-1-4), R ^{1 N141} and R ^{1 N142} are each independently preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and more preferably a methyl group, a propyl group, or an ethoxy group.

The compound represented by general formula (N-1-4) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content lower. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by formula (N-1-4) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

Furthermore, the compound represented by general formula (N-1-4) is preferably a compound selected from the group of compounds represented by formulas (N-1-4.1) to (N-1-4.18), preferably a compound represented by formulas (N-1-4.1) to (N-1-4.5), more preferably a compound represented by formulas (N-1-4.1), (N-1-4.2) and (N-1-4.4), and most preferably a compound represented by formula (N-1-4.4).

The compounds represented by formulas (N-1-4.1) to (N-1-4.14) can be used alone or in combination, but the preferred lower limit of the content of each of these compounds alone relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

The compound represented by general formula (N-1-5) is the following compound:

(In the formula, R ^N151 and R ^N152 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO— or —OCO—.)
In formula (N-1-5), R ^{1 N151} and R ^{1 N152} each independently represent preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and more preferably an ethyl group, a propyl group, or a butyl group.

The compound represented by general formula (N-1-5) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content lower, and when emphasis is placed on _TNI , it is more effective to set the content higher. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by formula (N-1-5) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

Furthermore, the compound represented by general formula (N-1-5) is preferably a compound selected from the group of compounds represented by formulas (N-1-5.1) to (N-1-5.6), and compounds represented by formulas (N-1-5.1), (N-1-5.2), and (N-1-5.4) are preferred.

The compounds represented by formula (N-1-5.1), formula (N-1-5.2), and formula (N-1-5.4) can be used alone or in combination, but the preferred lower limit of the content of each of these compounds alone relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

The compound represented by general formula (N-1-10) is the following compound:

(In the formula, R ^N1101 and R ^N1102 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO— or —OCO—.)
In general formula (N-1-10), R ^N1101 is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, a propyl group, or a butyl group. R ^N1102 is preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and more preferably an ethoxy group, a propoxy group, or a butoxy group.

Compounds represented by general formula (N-1-10) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content lower, and when emphasis is placed on _TNI , it is more effective to set the content higher. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by formula (N-1-10) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

Furthermore, the compound represented by general formula (N-1-10) is preferably a compound selected from the group of compounds represented by formulas (N-1-10.1) to (N-1-10.15), preferably a compound represented by formulas (N-1-10.1) to (N-1-10.5), more preferably a compound represented by formulas (N-1-10.1) and (N-1-10.2), and more preferably a compound represented by formula (N-1-10.2).

The compounds represented by formulae (N-1-10.1) to (N-1-10.15) can be used alone or in combination, but the preferred lower limit of the content of each of these compounds relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%, and the preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

The compound represented by general formula (N-1-11) is the following compound:

(In the formula, R ^N1111 and R ^N1112 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO—, or —OCO—, excluding the compound represented by formula (N1-I).)
In general formula (N-1-11), R is preferably ^an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, an ethyl group, a propyl group, or a butyl group. ^R is preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and more preferably an ethoxy group, a propoxy group, or a butoxy group.

Compounds represented by general formula (N-1-11) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content lower, and when emphasis is placed on _TNI , it is more effective to set the content higher. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by formula (N-1-11) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

Furthermore, the compound represented by general formula (N-1-11) is preferably a compound selected from the group of compounds represented by formulas (N-1-11.1) to (N-1-11.5), preferably a compound represented by formulas (N-1-11.1) to (N-1-11.3), and more preferably a compound represented by formula (N-1-11.2).

The compounds represented by formulas (N-1-11.1) to (N-1-11.5) can be used alone or in combination, but the preferred lower limit of the content of each of these compounds alone relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

The compound represented by general formula (N-1-12) is the following compound:

(In the formula, R ^N1121 and R ^N1122 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO— or —OCO—.)
In general formula (N-1-12), R ^N1121 is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an ethyl group or a propyl group. R ^N1122 is preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and more preferably an ethoxy group, a propoxy group or a butoxy group.

Compounds represented by general formula (N-1-12) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content lower. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by formula (N-1-12) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

The compound represented by general formula (N-1-13) is the following compound:

(In the formula, R ^N1131 and R ^N1132 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO— or —OCO—.)
In general formula (N-1-13), R ^N1131 is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an ethyl group, a propyl group, or a butyl group. R ^N1132 is preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and more preferably an ethoxy group, a propoxy group, or a butoxy group.

Compounds represented by general formula (N-1-13) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content higher. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by formula (N-1-13) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

The compound represented by general formula (N-1-14) is the following compound:

(In the formula, R ^N1141 and R ^N1142 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO— or —OCO—.)
In general formula (N-1-14), R ^N1141 is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an ethyl group, a propyl group, or a butyl group. R ^N1142 is preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and more preferably an ethoxy group, a propoxy group, or a butoxy group.

Compounds represented by general formula (N-1-14) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content lower. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by formula (N-1-14) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

The compound represented by general formula (N-1-15) is the following compound:

(In the formula, R ^N1151 and R ^N1152 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO— or —OCO—.)
In general formula (N-1-15), R ^N1151 is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an ethyl group, a propyl group, or a butyl group. R ^N1152 is preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and more preferably an ethoxy group, a propoxy group, or a butoxy group.

Compounds represented by general formula (N-1-15) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content higher. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by formula (N-1-15) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

The compound represented by general formula (N-1-16) is the following compound:

(In the formula, R ^N1161 and R ^N1162 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO— or —OCO—.)
In general formula (N-1-16), R ^N1161 is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an ethyl group, a propyl group, or a butyl group. R ^N1162 is preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and more preferably an ethoxy group, a propoxy group, or a butoxy group.

Compounds represented by general formula (N-1-16) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content higher. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by formula (N-1-16) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

The compound represented by general formula (N-1-17) is the following compound:

(In the formula, R ^N1171 and R ^N1172 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO— or —OCO—.)
In general formula (N-1-17), R ^N1171 is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an ethyl group, a propyl group, or a butyl group. R ^N1172 is preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and more preferably an ethoxy group, a propoxy group, or a butoxy group.

Compounds represented by general formula (N-1-17) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content higher. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by formula (N-1-17) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

The compound represented by general formula (N-1-18) is the following compound:

(In the formula, R ^N1181 and R ^N1182 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO—, or —OCO—, excluding the compound represented by formula (N1-V).)
In general formula (N-1-18), R ^N1181 is preferably an alkyl group having 1 to 5 carbon atoms, and more preferably a methyl group, ethyl group, propyl group, or butyl group. R ^N1182 is preferably an alkyl group having 1 to 5 carbon atoms or an alkoxy group having 1 to 4 carbon atoms, and more preferably an ethoxy group, propoxy group, or butoxy group.

Compounds represented by general formula (N-1-18) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content higher. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by formula (N-1-18) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

Furthermore, the compound represented by general formula (N-1-18) is preferably a compound selected from the group of compounds represented by formulas (N-1-18.1) to (N-1-18.4), preferably compounds represented by formulas (N-1-18.1) to (N-1-18.3), and more preferably compounds represented by formulas (N-1-18.2) and (N-1-18.3).

The compound represented by general formula (N-1-20) is the following compound:

(In the formula, R ^N1201 and R ^N1202 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO— or —OCO—.)
In general formula (N-1-20), R ¹²⁰¹ and R ¹²⁰² each independently represent preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an ethyl group, a propyl group, or a butyl group.

Compounds represented by general formula (N-1-20) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content higher. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by formula (N-1-20) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

The compound represented by general formula (N-1-22) is the following compound:

(In the formula, R ^N1221 and R ^N1222 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —C≡C—, —O—, —CO—, —COO—, or —OCO—), excluding the compound represented by formula (N1-VI).)
In general formula (N-1-22), R ¹²²¹ and R ¹²²² each independently represent preferably an alkyl group having 1 to 5 carbon atoms, and more preferably an ethyl group, a propyl group, or a butyl group.

Compounds represented by general formula (N-1-22) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

When emphasis is placed on improving Δε, it is preferable to set the content higher, when emphasis is placed on solubility at low temperatures, it is more effective to set the content higher, and when emphasis is placed on _TNI , it is more effective to set the content higher. Furthermore, when emphasis is placed on improving drop marks and image sticking properties, it is preferable to set the content in the middle range.

The preferred lower limit of the content of the compound represented by formula (N-1-22) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 0.5 mass%, 1 mass%, 1.5 mass%, 2 mass%, or 2.5 mass%. The preferred upper limit of the content is 6.5 mass%, 6 mass%, 5.5 mass%, or 5 mass%.

Furthermore, the compound represented by general formula (N-1-22) is preferably a compound selected from the group of compounds represented by formulas (N-1-22.1) to (N-1-22.5), preferably a compound represented by formulas (N-1-22.1) to (N-1-22.4), and more preferably a compound represented by formulas (N-1-22.1) to (N-1-22.3).

Of these, as compound (N-1) having a dielectric anisotropy more negative than -2, it is preferable to use one or more compounds represented by compound (N-1-11). A combination of one or more of compounds (N-1-1), (N-1-4), and (N-1-5) with one or more of compounds (N-1-11) and (N-1-18) is preferred, and a combination of one or more of compounds (N-1-1) and (N-1-4) with compound (N-1-11) is even more preferred.

The liquid crystal composition of the present invention contains, as an essential component, a compound represented by formula (L-10-1) that is a nearly dielectrically neutral compound (-2<Δε<2).

By using a compound represented by formula (L-10-1) in combination with a liquid crystal compound having the above-mentioned specific structure and negative dielectric anisotropy in the liquid crystal composition of the present invention, a liquid crystal composition with excellent storage stability can be obtained, and the physical properties of the resulting liquid crystal display device, such as high-speed response, can be improved. The preferred lower limit of the content of the compound represented by formula (L-1-10) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 2% by mass, 4% by mass, 5% by mass, 10% by mass, 15% by mass, 16% by mass, 17% by mass, 18% by mass, 20% by mass, 21% by mass, 22% by mass, or 23% by mass. The preferred upper limit of the content is 38% by mass, 35% by mass, 32% by mass, 30% by mass, or 29% by mass relative to the total amount of the liquid crystal composition of the present invention.

The liquid crystal composition of the present invention preferably further contains a compound represented by formula (L-10-2) as a nearly dielectrically neutral compound (-2<Δε<2).

By using a compound represented by formula (L-10-2) in combination with a liquid crystal compound having the specific structure and negative dielectric anisotropy and a liquid crystal compound represented by formula (L-10-1) in the liquid crystal composition of the present invention, a liquid crystal composition with excellent storage stability can be obtained, and the physical properties of the resulting liquid crystal display device, such as high-speed response, can be improved. The preferred lower limit of the content of the compound represented by formula (L-10-2) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 3% by mass, 5% by mass, 8% by mass, or 10% by mass. The preferred upper limit of the content is 40% by mass, 35% by mass, 25% by mass, 22% by mass, 20% by mass, 17% by mass, or 15% by mass, relative to the total amount of the liquid crystal composition of the present invention.

The liquid crystal composition of the present invention preferably further contains one or more liquid crystal compounds represented by general formula (L) which are dielectrically nearly neutral (-2<Δε<2).
(Compound (L))

(wherein R ^L1 and R ^L2 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —CH═CH—, —C≡C—, —O—, —CO—, —COO— or —OCO—;
n ^L1 represents 0, 1, 2 or 3;
A ^L1 , A ^L2 and A ^L3 each independently represent (a) a 1,4-cyclohexylene group (in which one —CH ₂ — or two or more non-adjacent —CH ₂ — groups may be replaced with —O—), and (b) a 1,4-phenylene group (in which one —CH= or two or more non-adjacent —CH= groups may be replaced with —N=).
(c) a naphthalene-2,6-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, or a decahydronaphthalene-2,6-diyl group (one —CH= or two or more non-adjacent —CH= groups in the naphthalene-2,6-diyl group or the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced by —N=).
wherein the groups (a), (b) and (c) may each independently be substituted with a cyano group, a fluorine atom or a chlorine atom;
Z ^L1 and Z ^L2 each independently represent a single bond, —CH ₂ CH ₂ —, —(CH ₂ ) ₄ —, —OCH ₂ —, —CH ₂ O—, —COO—, —OCO—, —OCF ₂ —, —CF ₂ O—, —CH═N—N═CH—, —CH═CH—, —CF═CF— or —C≡C—;
When n ^L1 is 2 or 3 and a plurality of A ^L2s are present, they may be the same or different, and when n ^L1 is 2 or 3 and a plurality of Z ^L2s are present, they may be the same or different, except for the compounds represented by general formula (N1), formula (N1-I), formula (N1-II), formula (N1-III), formula (N1-IV), formula (N1-V), formula (N1-VI), formula (L-10-1) and formula (L-10-2).
The compound represented by general formula (L) may be used alone or in combination. There is no particular limitation on the type of compound that can be combined, but an appropriate combination is used depending on the desired performance, such as solubility at low temperature, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, the type of compound used is one type. Alternatively, in another embodiment of the present invention, the type is two, three, four, five, six, seven, eight, nine, or ten or more types.

In the liquid crystal composition of the present invention, the content of the compound represented by general formula (L) must be appropriately adjusted depending on the required performance, such as solubility at low temperatures, transition temperature, electrical reliability, birefringence, process compatibility, drop marks, image sticking, and dielectric anisotropy.

When reliability is important, it is preferable that ^R and ^R are both alkyl groups; when reducing the volatility of the compound is important, it is preferable that they are alkoxy groups; and when reducing viscosity is important, it is preferable that at least one of them is an alkenyl group.

When the ring structure to which R ^L1 and R ^L2 are bonded is a phenyl group (aromatic), they are preferably a linear alkyl group having 1 to 5 carbon atoms, a linear alkoxy group having 1 to 4 carbon atoms, or an alkenyl group having 4 to 5 carbon atoms, and when the ring structure to which they are bonded is a saturated ring structure such as cyclohexane, pyran, or dioxane, they are preferably a linear alkyl group having 1 to 5 carbon atoms, a linear alkoxy group having 1 to 4 carbon atoms, or a linear alkenyl group having 2 to 5 carbon atoms. In order to stabilize a nematic phase, it is preferable that the total number of carbon atoms and, if present, oxygen atoms is 5 or less, and they are preferably linear.

The alkenyl group is preferably selected from groups represented by formulas (R1) to (R9). (The black dots in each formula represent carbon atoms in the ring structure.)

^nL1 is preferably 0 when emphasis is placed on response speed, preferably 2 or 3 in order to improve the maximum temperature of the nematic phase, and preferably 1 in order to strike a balance between these. In addition, it is preferable to combine compounds with different values in order to satisfy the properties required of the composition.

A ^L1 , A ^L2 and A ^L3 are preferably aromatic when it is required to increase Δn, and are preferably aliphatic in order to improve the response speed. Each of A L1 , A L2 and A L3 independently represents preferably a trans-1,4-cyclohexylene group, a 1,4-phenylene group, a 2-fluoro-1,4-phenylene group, a 3-fluoro-1,4-phenylene group, a 3,5-difluoro-1,4-phenylene group, a 1,4-cyclohexenylene group, a 1,4-bicyclo[2.2.2]octylene group, a piperidine-1,4-diyl group, a naphthalene-2,6-diyl group, a decahydronaphthalene-2,6-diyl group or a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, and more preferably represents the following structure:

More preferably, it represents a trans-1,4-cyclohexylene group or a 1,4-phenylene group.

When emphasis is placed on response speed, Z ^L1 and Z ^L2 are preferably single bonds.

The number of halogen atoms in the molecule is preferably 0 or 1.

The compound represented by general formula (L) is preferably a compound selected from the group of compounds represented by general formula (ii-1), general formula (ii-3), general formula (ii-4), general formula (L-2), general formula (L-4), general formula (L-5), general formula (L-6), and/or general formula (L-7).

The compound represented by general formula (L) is preferably a compound represented by general formula (ii-1) (excluding compounds represented by formulas (L-10-1) and (L-10-2)).

(In the formula, R ⁱⁱ¹¹ represents a hydrogen atom or a methyl group, R ⁱⁱ² represents an alkyl group having 1 to 10 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —CH═CH—, —C≡C—, —O—, —CO—, —COO—, or —OCO—.)
The preferred lower limit of the content is 0 mass %, 1 mass %, or 2 mass %, relative to the total amount of the liquid crystal compound contained in the liquid crystal composition of the present invention, and the preferred upper limit of the content is 7 mass %, 5 mass %, or 3 mass %, relative to the total amount of the liquid crystal compound contained in the liquid crystal composition of the present invention.

The compound represented by general formula (ii-1) is preferably a compound selected from the group of compounds represented by formulas (ii-1.11) to (ii-1.14).

The preferred lower limit of the content of each of the compounds represented by formulas (ii-1.11) to (ii-1.14) or the total content of the compounds relative to the total amount of the liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 1 mass%, or 2 mass%, relative to the total amount of the liquid crystal compounds contained in the liquid crystal composition of the present invention. The preferred upper limit of the content is 7 mass%, 5 mass%, or 3 mass%, relative to the total amount of the liquid crystal compounds contained in the liquid crystal composition of the present invention.

Furthermore, the compound represented by general formula (ii-1) is preferably a compound selected from the group of compounds represented by formulas (ii-1.21) to (ii-1.24), and is preferably a compound represented by formulas (ii-1.23) to (ii-1.24).

The preferred lower limit of the content of each of the compounds represented by formulas (ii-1.21) to (ii-1.24) or the total content of the compounds relative to the total amount of the liquid crystal composition of the present invention is 0 mass%, 1 mass%, or 2 mass%, relative to the total amount of the liquid crystal compounds contained in the liquid crystal composition of the present invention. The preferred upper limit of the content is 7 mass%, 5 mass%, or 3 mass%, relative to the total amount of the liquid crystal compounds contained in the liquid crystal composition of the present invention.

Furthermore, the compound represented by general formula (ii-1) is preferably a compound selected from the group of compounds represented by formulas (ii-1.31) and (ii-1.41).

The preferred lower limit of the content of each of the compounds represented by formulas (ii-1.31) to (ii-1.41) or the total content of the compounds relative to the total amount of the liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 1 mass%, or 2 mass%, relative to the total amount of the liquid crystal compounds contained in the liquid crystal composition of the present invention. The preferred upper limit of the content is 7 mass%, 5 mass%, or 3 mass%, relative to the total amount of the liquid crystal compounds contained in the liquid crystal composition of the present invention.

The compound represented by general formula (L) is preferably a compound selected from the group of compounds represented by general formulas (ii-3) and/or (ii-4).

(In the formula, R ⁱⁱ³¹ and R ⁱⁱ⁴¹ each independently represent an alkyl group having 1 to 10 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —CH═CH—, —C≡C—, —O—, —CO—, —COO—, or —OCO—.)
R ⁱⁱ³¹ and R ⁱⁱ³² are preferably a linear alkyl group having 1 to 5 carbon atoms, a linear alkoxy group having 1 to 4 carbon atoms, or a linear alkenyl group having 2 to 5 carbon atoms.

The preferred lower limit of the content of the compound represented by formula (ii-3) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 1 mass%, or 2 mass%, relative to the total amount of the liquid crystal composition of the present invention. The preferred upper limit of the content is 7 mass%, 5 mass%, or 3 mass%, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention.

The preferred lower limit of the content of the compound represented by formula (ii-4) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 1 mass%, or 2 mass%, relative to the total amount of the liquid crystal composition of the present invention. The preferred upper limit of the content is 7 mass%, 5 mass%, or 3 mass%, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention.

Furthermore, the compounds represented by general formulas (ii-3) and (ii-4) are preferably compounds selected from the group of compounds represented by formulas (ii-3.1) to (ii-4.3), and are preferably compounds represented by formula (ii-3.2) or formula (ii-4.2).

The preferred lower limit of the content of each of the compounds represented by formulas (ii-3.1) to (ii-4.3) or the total content of the compounds relative to the total amount of the liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 1 mass%, or 2 mass%, relative to the total amount of the liquid crystal compounds contained in the liquid crystal composition of the present invention. The preferred upper limit of the content is 7 mass%, 5 mass%, or 3 mass%, relative to the total amount of the liquid crystal compounds contained in the liquid crystal composition of the present invention.

The compound represented by general formula (L) is preferably a compound selected from the group of compounds represented by general formula (L-2).

The compound represented by general formula (L-2) is the following compound:

(In the formula, R ^L21 and R ^L22 each independently represent an alkyl group having 1 to 10 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —CH═CH—, —C≡C—, —O—, —CO—, —COO—, or —OCO—.)
R ^L21 is preferably an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, and R ^L22 is preferably an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 4 to 5 carbon atoms or an alkoxy group having 1 to 4 carbon atoms.

The compound represented by general formula (L-2) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

The preferred lower limit of the total content of the compounds represented by formula (L-2) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 1 mass%, or 2 mass%, relative to the total amount of the liquid crystal composition of the present invention. The preferred upper limit of the content is 7 mass%, 5 mass%, or 3 mass%, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention.

Furthermore, the compound represented by general formula (L-2) is preferably a compound selected from the group of compounds represented by formulas (L-2.1) to (L-2.6), and is preferably a compound represented by formulas (L-2.1), (L-2.3), (L-2.4), and (L-2.6).

The preferred lower limit of the content of each of the compounds represented by formulas (L-2.1) to (L-2.6) or the total content of the compounds relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 1 mass%, or 2 mass%, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention. The preferred upper limit of the content is 7 mass%, 5 mass%, or 3 mass%, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention.

The compound represented by general formula (L) is preferably a compound selected from the group of compounds represented by general formula (L-4).

The compound represented by general formula (L-4) is the following compound:

(In the formula, R ^L41 and R ^L42 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —CH═CH—, —C≡C—, —O—, —CO—, —COO—, or —OCO—.)
R ^L41 is preferably an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, and R ^L42 is preferably an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 4 to 5 carbon atoms or an alkoxy group having 1 to 4 carbon atoms.

The compound represented by general formula (L-4) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

The preferred lower limit of the total content of the compounds represented by formula (L-4) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 1 mass%, or 2 mass%, relative to the total amount of the liquid crystal composition of the present invention. The preferred upper limit of the content is 7 mass%, 5 mass%, or 3 mass%, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention.

The compound represented by general formula (L-4) is preferably a compound represented by formula (L-4.1) to formula (L-4.3), for example.

Depending on the desired performance, such as low-temperature solubility, transition temperature, electrical reliability, and birefringence, the composition may contain a compound represented by formula (L-4.1), a compound represented by formula (L-4.2), both a compound represented by formula (L-4.1) and a compound represented by formula (L-4.2), or all of the compounds represented by formulas (L-4.1) to (L-4.3).

The preferred lower limit of the content of the compound represented by formula (L-4.1) or formula (L-4.2) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0% by mass, 1% by mass, 3% by mass, 5% by mass, 7% by mass, or 9% by mass, and the preferred upper limit is 15% by mass, 13% by mass, 10% by mass, 8% by mass, or 5% by mass.

When both a compound represented by formula (L-4.1) and a compound represented by formula (L-4.2) are contained, the preferred lower limit of the content of both compounds relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0% by mass, 1% by mass, 3% by mass, 5% by mass, 7% by mass, or 9%, and the preferred upper limit is 15% by mass, 13% by mass, 10% by mass, 8% by mass, or 5% by mass.

The compound represented by general formula (L-4) is preferably a compound represented by formula (L-4.4) to formula (L-4.6), and is preferably a compound represented by formula (L-4.4).

Depending on the desired performance, such as low-temperature solubility, transition temperature, electrical reliability, and birefringence, the material may contain a compound represented by formula (L-4.4), a compound represented by formula (L-4.5), or both a compound represented by formula (L-4.4) and a compound represented by formula (L-4.5).

The preferred lower limit of the content of the compounds represented by formula (L-4.4) and/or formula (L-4.5) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 3 mass%, 5 mass%, 7 mass%, 9 mass%, or 10 mass%, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention. The preferred upper limit of the total content is 25 mass%, 20 mass%, 18 mass%, 15 mass%, 13 mass%, or 11 mass%, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention.

The compound represented by general formula (L-4) is preferably a compound represented by formula (L-4.7) to formula (L-4.10), and particularly preferably a compound represented by formula (L-4.9).

The preferred lower limit of the content of the compounds represented by formula (L-4.7), formula (L-4.8), formula (L-4.9), and/or formula (L-4.10) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0% by mass, 1% by mass, 3% by mass, 5% by mass, 7% by mass, or 9% by mass, and the preferred upper limit is 15% by mass, 13% by mass, 10% by mass, 8% by mass, or 5% by mass.

The compound represented by general formula (L) is preferably a compound selected from the group of compounds represented by general formula (L-5).

The compound represented by general formula (L-5) is the following compound:

(In the formula, R ^L51 and R ^L52 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —CH═CH—, —C≡C—, —O—, —CO—, —COO— or —OCO—.)
R ^L51 is preferably an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, and R ^L52 is preferably an alkyl group having 1 to 5 carbon atoms, an alkenyl group having 4 to 5 carbon atoms or an alkoxy group having 1 to 4 carbon atoms.

The compound represented by general formula (L-5) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

The preferred lower limit of the total content of the compounds represented by formula (L-5) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 1 mass%, or 2 mass%, relative to the total amount of the liquid crystal composition of the present invention. The preferred upper limit of the content is 7 mass%, 5 mass%, or 3 mass%, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention.

The compound represented by general formula (L-5) is preferably a compound represented by formula (L-5.1), formula (L-5.2), or formula (L-5.3), and is particularly preferably a compound represented by formula (L-5.1).

When these compounds are used alone or in combination with one another relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention, the preferred lower limit of their content is 0% by mass, 1% by mass, 3% by mass, 5% by mass, 7% by mass, or 9% by mass, and the preferred upper limit is 15% by mass, 13% by mass, 10% by mass, 8% by mass, or 5% by mass.

The compound represented by general formula (L-5) is preferably a compound represented by formula (L-5.3) or formula (L-5.4).

The preferred lower limit of the content of these compounds relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 1 mass%, 3 mass%, 5 mass%, 7 mass%, or 9 mass%, and the preferred upper limit is 15 mass%, 13 mass%, 10 mass%, 8 mass%, or 5 mass%.

The compound represented by general formula (L-5) is preferably a compound selected from the group of compounds represented by formulas (L-5.5) to (L-5.7), and is particularly preferably a compound represented by formula (L-5.7).

The preferred lower limit of the content of these compounds relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 1 mass%, 3 mass%, 5 mass%, 7 mass%, or 9 mass%, and the preferred upper limit is 15 mass%, 13 mass%, 10 mass%, 8 mass%, or 5 mass%.

The compound represented by general formula (L) is preferably a compound selected from the group of compounds represented by general formula (L-6).

The compound represented by general formula (L-6) is the following compound:

(In the formula, R ^L61 and R ^L62 each independently represent an alkyl group having 1 to 10 carbon atoms, one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —CH═CH—, —C≡C—, —O—, —CO—, —COO— or —OCO—, and X ^L61 and X ^L62 each independently represent a hydrogen atom or a fluorine atom.)
R 1 ^L61 and R ^{1 L62} are preferably each independently an alkyl group having 1 to 5 carbon atoms or an alkenyl group having 2 to 5 carbon atoms, and it is preferred that one of X ^{1 L61} and X ^{1 L62} is a fluorine atom and the other is a hydrogen atom.

The compound represented by general formula (L-6) can be used alone, or two or more compounds can be used in combination. There are no particular restrictions on the types of compounds that can be combined, but appropriate combinations are used depending on the desired performance, such as solubility at low temperatures, transition temperature, electrical reliability, and birefringence. In one embodiment of the present invention, for example, one, two, three, four, or five or more types of compounds are used.

The preferred lower limit of the total content of the compounds represented by formula (L-6) relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention is 0 mass%, 1 mass%, or 2 mass%, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention. The preferred upper limit of the content is 7 mass%, 5 mass%, or 3 mass%, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention.

Preferable upper limits for the total content of compounds having an alkenyl group relative to the total amount of liquid crystal compounds contained in the liquid crystal composition of the present invention are 30% by mass, 25% by mass, 20% by mass, 15% by mass, 13% by mass, and 10% by mass. Although the inclusion of a compound having an alkenyl group is effective in improving the response speed, it can also have undesirable effects in terms of reliability and wavelength dispersion of Δn. Therefore, it is preferable that the compound represented by formula (L) and the compound represented by formula (N-1) are compounds that do not have an alkenyl group, and it is more preferable that the composition does not substantially contain any compounds having an alkenyl group other than the compound represented by formula (IV).

It is preferable that the composition of the present invention does not contain compounds with a structure in which oxygen atoms are bonded together, such as a peroxy acid (-CO-OO-) structure, within the molecule.

When the reliability and long-term stability of the composition are important, the content of compounds having a carbonyl group is preferably 5% by mass or less, more preferably 3% by mass or less, even more preferably 1% by mass or less, and most preferably substantially none, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition.

When stability under UV irradiation is important, the content of compounds substituted with chlorine atoms is preferably 15% by mass or less, more preferably 10% by mass or less, more preferably 8% by mass or less, more preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably substantially none, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition.

It is preferable to increase the content of compounds whose intramolecular ring structures are all six-membered rings, and the content of compounds whose intramolecular ring structures are all six-membered rings is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more, of the total amount of liquid crystal compounds contained in the liquid crystal composition. It is most preferable that the composition be composed essentially of compounds whose intramolecular ring structures are all six-membered rings.

In order to improve the tilt stability of the composition, it is preferable to increase the content of compounds having alkyl and alkoxy groups in the side chain, and the content of compounds having alkyl and alkoxy groups in the side chain is preferably 85% by mass or more, preferably 87% by mass or more, preferably 90% by mass or more, preferably 93% by mass or more, preferably 95% by mass or more, preferably 98% by mass or more, and more preferably substantially 100% by mass, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition. Substantially 100% by mass means 100% by mass excluding polymerizable compounds, stabilizers, and additionally mixed impurities.

In order to prevent deterioration of the composition due to oxidation, it is preferable to reduce the content of compounds having a cyclohexenylene group as a ring structure, and the content of compounds having a cyclohexenylene group is preferably 10% by mass or less, more preferably 8% by mass or less, more preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably substantially none, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition.

When improving viscosity and Tni is important, it is preferable to reduce the content of compounds having a 2-methylbenzene-1,4-diyl group in the molecule, in which a hydrogen atom may be substituted with a halogen, and the content of compounds having a 2-methylbenzene-1,4-diyl group in the molecule is preferably 10% by mass or less, more preferably 8% by mass or less, more preferably 5% by mass or less, and more preferably 3% by mass or less, relative to the total amount of liquid crystal compounds contained in the liquid crystal composition, and even more preferably substantially none.

In this application, "substantially free" means "free of all substances except those that are unintentionally contained."
(Polymerizable compound)
The liquid crystal composition of the present invention may contain a polymerizable compound in order to produce a liquid crystal display element of a PSA mode, a PSVA mode, a horizontal electric field type PSA mode, a horizontal electric field type PSVA mode, etc. Examples of the polymerizable compound that can be used include photopolymerizable monomers that undergo polymerization by energy rays such as light, and examples of the polymerizable compound include polymerizable compounds having a liquid crystal skeleton in which multiple six-membered rings are linked together, such as biphenyl derivatives and terphenyl derivatives.

More specifically, polymerizable compounds represented by general formula (P) are preferred.

(In the above general formula (P), R ^p1 represents a hydrogen atom, a fluorine atom, a cyano group, an alkyl group having 1 to 15 carbon atoms, or -Sp ^p2 -P ^p2 , one or two or more non-adjacent -CH ₂ - groups in the alkyl group may each independently be substituted with -CH═CH-, -C≡C-, -O-, -CO-, -COO-, or -OCO-, and one or two or more hydrogen atoms in the alkyl group may each independently be substituted with a cyano group, a fluorine atom, or a chlorine atom;
P ^p1 and P ^p2 each independently represent a group represented by the general formula (P ^p1 -1) to the formula (P ^p1 -9):

(In the formula, R ^p11 and R ^p12 each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms; W ^p11 represents a single bond, —O—, —COO—, or a methylene group; and t ^p11 represents 0, 1, or 2; however, when a plurality of R ^p11 , R ^p12 , W ^p11 , and/or t ^p11 are present in a molecule, they may be the same or different.)
represents one of the following:
Sp ^p1 and Sp ^p2 each independently represent a single bond or a spacer group;
Z ^p1 and Z ^p2 each independently represent a single bond, —O—, —S—, —CH 2 —, —OCH ₂ —, —CH ₂ O—, —CO—, —C _{2 H 4 —} , —COO—, —OCO— _, —OCOOCH ₂ —, —CH ₂ OCOO—, —OCH ₂ CH ₂ O—, —CO—NR ^ZP1 —, —NR ^ZP1 —CO—, —SCH ₂ —, —CH ₂ S—, —CH═CR ^ZP1 —COO—, —CH═CR ZP1 —OCO—, —COO-CR ZP1 ═CH—, —OCO-CR ^ZP1 ═CH—, —COO-CR ^ZP1 ═CH—COO—, —COO-CR ^{ZP1 ═CH} —COO—, —COO-CR ^ZP1 ═CH—OCO—, —OCO—CR ^ZP1 ═CH—COO—, —OCO—CR ^ZP1 ═CH—OCO—, —(CH ₂ ) _z -COO—, —(CH 2 ) ₂ -OCO—, —OCO—(CH ₂ ) ₂ —, —(C═O)—O—(CH ₂ ) ₂ —, —CH═CH—, —CF═CF—, —CF═CH—, —CH═CF—, —CF ₂ —, —CF ₂ O—, —OCF ₂ —, —CF ₂ CH ₂ —, —CH ₂ CF ₂ —, —CF ₂ CF ₂ —, or —C≡C— (wherein R ^ZP1 each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, but if _R When there are multiple ^ZP1s , they may be the same or different.
represents
A ^p1 , A ^p2 , and A ^p3 each independently represent
(a ^p ) a 1,4-cyclohexylene group (in which one —CH ₂ — or two or more non-adjacent —CH ₂ — groups may be replaced by —O—).
(b ^p ) a 1,4-phenylene group (one —CH= or two or more non-adjacent —CH= groups in this group may be replaced by —N=), and (c ^p ) a naphthalene-2,6-diyl group, a naphthalene-1,4-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, a decahydronaphthalene-2,6-diyl group, a phenanthrene-2,7-diyl group, or an anthracene-2,6-diyl group (one —CH= or two or more non-adjacent —CH= groups in these groups may be replaced by —N=).
one or more hydrogen atoms present in the above groups (a ^p ), (b ^p ) and (c ^p ) may each independently be substituted with a halogen atom, a cyano group, an alkyl group having 1 to 8 carbon atoms or -Sp ^p2 -P ^p2 , and one or two or more non-adjacent -CH ₂ - groups in the alkyl group may each independently be substituted with -CH═CH-, -C≡C-, -O-, -CO-, -COO- or -OCO-;
m ^p1 represents 0, 1, 2 or 3, and when a plurality of Z ^p1 , A ^p2 , Sp ^p2 and/or P ^p2 are present in a molecule, they may be the same or different, but A ^p3 represents a single bond when m ^p1 is 0 and A ^p1 is a phenanthrene-2,7-diyl group or an anthracene-2,6-diyl group.
In formula (P), R ^p1 is preferably -Sp ^p2 -P ^p2 .

P ^p1 and P ^p2 each independently preferably represent any one of formulas (P ^p1 -1) to (P ^p1 -3), and more preferably (P ^p1 -1).

It is preferable that R ^p11 and R ^p12 each independently represent a hydrogen atom or a methyl group.

t ^p11 is preferably 0 or 1.

W ^p11 is preferably a single bond, a methylene group or an ethylene group.

m ^p1 is preferably 0, 1 or 2, and 0 or 1 is more preferred.

Z ^p1 and Z ^p2 are each independently preferably a single bond, —OCH ₂ —, —CH ₂ O—, —CO—, —C ₂ H ₄ —, —COO—, —OCO—, —COOC _{2 H 4 —, —OCOC 2 H 4 —, —C 2 H 4 OCO—} , —C ₂ H ₄ COO—, —CH═CH—, —CF ₂ —, —CF ₂ O—, — ₍ CH 2 ) ₂ —COO—, —(CH ₂ ) ₂ —OCO—, —OCO—(CH ₂ ) ₂ —, _—CH═CH —COO—, —COO-CH═CH—, —OCOCH═CH—, —COO- _{(CH 2 ) 2} —, —OCF ₂ — or —C≡C—, and are each independently preferably a single bond, —OCH ₂ -, -CH ₂ O-, -C ₂ H ₄ -, -COO-, -OCO-, -COOC 2 H ₄ -, -OCOC ₂ H ₄ -, -C ₂ H 4 OCO-, -C ₂ H ₄ COO-, -CH=CH-, -(CH ₂ ) ₂ -COO-, -(CH ₂ ) ₂ -OCO-, -OCO-(CH ₂ ) _{2 -} , -CH=CH-COO-, -COO-CH=CH-, -OCOCH=CH-, -COO-(CH ₂ ) ₂ - or -C≡C- is preferred _, and only one of -OCH ₂ -, -CH ₂ O-, -C ₂ H ₄ -, -COO-, -OCO-, -COOC ₂ H ₄ It is preferred that only one of the groups in the molecule is -OCH ₂ -, -CH ₂ O-, -C ₂ H ₄ OCO-, -C _{2 H 4} COO-, -CH=CH-, -(CH ₂ ) ₂ -COO-, -(CH ₂ ) 2 -OCO-, -OCO-(CH ₂ ) ₂ -, -CH=CH-COO-, -COO-CH=CH-, -OCOCH=CH-, -COO-(CH ₂ ) ₂ - or -C≡C-, and the others are all single bonds, and it is preferred that only one of the groups in the molecule is -OCH ₂ -, -CH ₂ O-, -C ₂ H ₄ -, -COO- or -OCO-, and the others are all single bonds, and it is more preferred that all are single bonds.

It is also preferred that only one of Z ^p1 and Z ^p2 present in the molecule is a linking group selected from the group consisting of -CH=CH-COO-, -COO-CH=CH-, -(CH ₂ ) ₂ -COO-, -(CH ₂ ) ₂ -OCO-, -O-CO-(CH ₂ ) ₂ - and -COO-(CH ₂ ) ₂ -, and the other is a single bond.

Sp ^p1 and Sp ^p2 each independently represent a single bond or a spacer group, and the spacer group is preferably an alkylene group having 1 to 30 carbon atoms, and -CH ₂ - in the alkylene group may be substituted with -O-, -CO-, -COO-, -OCO-, -CH═CH- or -C≡C- as long as the oxygen atoms are not directly linked to each other, and a hydrogen atom in the alkylene group may be substituted with a halogen atom, but a linear alkylene group having 1 to 10 carbon atoms or a single bond is preferred.
A ^p1 , A ^p2 , and A ^p3 each independently represent preferably a 1,4-phenylene group, a 1,4-cyclohexylene group, or a naphthalene-1,4-diyl group, more preferably a 1,4-phenylene group or a 1,4-cyclohexylene group, and most preferably a 1,4-phenylene group. The 1,4-phenylene group is preferably substituted with one fluorine atom, one methyl group, or one methoxy group to improve compatibility with liquid crystal compounds.

The total content of the compounds represented by general formula (P) is preferably 0.05 to 10% by mass, more preferably 0.1 to 8% by mass, more preferably 0.1 to 5% by mass, more preferably 0.1 to 3% by mass, more preferably 0.2 to 2% by mass, more preferably 0.2 to 1.3% by mass, more preferably 0.2 to 1% by mass, and more preferably 0.2 to 0.56% by mass, relative to the total amount (100% by mass) of liquid crystal compounds contained in the liquid crystal composition containing the compound represented by general formula (P) of the present application.

Preferable lower limits for the total content of compounds represented by formula (P) are 0.01% by mass, 0.03% by mass, 0.05% by mass, 0.08% by mass, 0.1% by mass, 0.15% by mass, 0.2% by mass, 0.25% by mass, and 0.3% by mass, relative to the total amount (100% by mass) of liquid crystal compounds contained in the liquid crystal composition containing the compound represented by general formula (P) of the present application.

Preferable upper limits for the total content of compounds represented by formula (P) are 10% by mass, 8% by mass, 5% by mass, 3% by mass, 1.5% by mass, 1.2% by mass, 1% by mass, 0.8% by mass, and 0.5% by mass, relative to 100% by mass of the total amount of liquid crystal compounds contained in the liquid crystal composition containing the compound represented by formula (P) of the present application.

If the content is too low, the effect of adding the compound represented by formula (P) will not be apparent, and problems such as a weak alignment control force for the liquid crystal composition or a weakening over time will occur. If the content is too high, problems such as a large amount remaining after curing, long curing times, and reduced reliability of the liquid crystal will occur. For this reason, the content is set taking these factors into consideration.

Preferred examples of compounds represented by formula (P) include polymerizable compounds represented by the following formulas (P-1-1) to (P-1-54).

(In the formula, P ^p11 , P ^p12 , Sp ^p11 and Sp ^p12 have the same meanings as P ^p1 , P ^p2 , Sp ^p1 and Sp ^p2 in general formula (P), respectively.)
Preferred examples of the compound represented by general formula (P) according to the present invention include polymerizable compounds represented by the following formulae (P-2-1) to (P-2-29).

(In the formula, P ^p21 , P ^p22 , Sp ^p21 and Sp ^p22 have the same meanings as P ^p1 , P ^p2 , Sp ^p1 and Sp ^p2 in general formula (P), respectively.)
Preferred examples of the compound represented by general formula (P) according to the present invention include polymerizable compounds represented by the following formulae (P-3-1) to (P-3-15).

(In the formula, P ^p31 , P ^p32 , Sp ^p31 and Sp ^p32 have the same meanings as P ^p1 , P ^p2 , Sp ^p1 and Sp ^p2 in general formula (P), respectively.)
Preferred examples of the compound represented by general formula (P) according to the present invention include polymerizable compounds represented by the following formulae (P-4-1) to (P-4-19).

(In the formula, P ^p41 , P ^p42 , Sp ^p41 and Sp ^p42 have the same meanings as P ^p1 , P ^p2 , Sp ^p1 and Sp ^p2 in general formula (P), respectively, and multiple P ^{p42 s} and Sp ^p42 s may be the same or different.)
When a polymerizable monomer is used in the present invention, the polymerizable monomer may be used alone or in combination of two or more. In particular, a combination of two or more polymerizable monomers having different polymerization reaction rates is preferred, since it allows the polymerization reaction rate to be appropriately controlled, the amount of residual monomer to be reduced, and an appropriate pretilt angle to be imparted. Furthermore, from the viewpoint of the balance between storage stability and polymerization reaction rate, it is preferred to use two or more polymerizable monomers in combination. When two or more polymerizable monomers are used, it is preferred to use two or more compounds represented by the above formula (P) in combination.

The total content of the compounds represented by general formula (P) is preferably 0.05 to 1% by mass, more preferably 0.1 to 8% by mass, more preferably 0.1 to 5% by mass, more preferably 0.1 to 3% by mass, more preferably 0.2 to 2% by mass, more preferably 0.2 to 1.3% by mass, more preferably 0.2 to 1% by mass, and more preferably 0.2 to 0.56% by mass, relative to the total amount (100% by mass) of liquid crystal compounds contained in the liquid crystal composition containing these compounds.

Preferable lower limits for the total content of compounds represented by general formula (P) are 0.01% by mass, 0.03% by mass, 0.05% by mass, 0.08% by mass, 0.1% by mass, 0.15% by mass, 0.2% by mass, 0.25% by mass, and 0.3% by mass, relative to the total amount (100% by mass) of liquid crystal compounds contained in the liquid crystal composition containing these compounds.

Preferable upper limits for the total content of compounds represented by general formula (P) are 10% by mass, 8% by mass, 5% by mass, 3% by mass, 1.5% by mass, 1.2% by mass, 1% by mass, 0.8% by mass, and 0.5% by mass, relative to 100% by mass of the total amount of liquid crystal compounds contained in the liquid crystal composition containing these compounds.

If the content is too small, the effect of adding the compound represented by general formula (P) is not readily apparent, and problems such as a weak alignment-controlling force of the liquid crystal composition or a weakening over time occur, while if the content is too large, problems such as a large amount remaining after curing, a long curing time, a decrease in the reliability of the liquid crystal, etc. Therefore, the content is set by taking these factors into consideration.
(Other additives)
The liquid crystal composition of the present invention preferably contains one or more additives such as antioxidants, light stabilizers such as HALS, dyes, dichroic dyes, and fluorescent dyes.

By including an antioxidant and a light stabilizer in the liquid crystal composition of the present invention, light leakage can be further suppressed or prevented in a liquid crystal display device using the composition. As the antioxidant and light stabilizer, compound (Q) having the following structure is preferred.

(In the formula, R and ^Q represent a hydroxyl group, a hydrogen atom, or a linear or branched alkyl group having 1 to 22 carbon atoms, and one or more _CH groups in the alkyl group may be substituted with —O—, —CH═CH—, —CO—, —OCO—, —COO—, —C≡C—, —CF ₂ O—, or —OCF ₂ — so that the oxygen atom is not directly adjacent, and * is used to bond to other structures.)
R ^Q represents a linear or branched alkyl group having 1 to 22 carbon atoms, and one or more _CH2 groups in the alkyl group may be substituted with -O-, -CH=CH-, -CO-, -OCO-, -COO-, -C≡C-, -CF2O-, or _-OCF2- so that oxygen atoms are not directly adjacent. However, a linear alkyl group, a linear alkoxy group, a linear alkyl group in which _{one CH2} group is substituted with -OCO- or -COO-, a branched alkyl group, a branched alkoxy group, or a branched alkyl group in which one _CH2 group is substituted with -OCO- or -COO- having 1 to 10 carbon atoms is preferred, and a linear alkyl group, a linear alkyl group in which one _CH2 group is substituted with -OCO- or -COO-, a branched alkyl group, a branched alkoxy group, or a branched alkyl group in which one _CH2 group is substituted with -OCO- or -COO- having 1 to 20 carbon atoms is more preferred.

More specifically, compound (Q) is preferably a compound represented by the following general formulas (Q-a) to (Q-d).

In the formula, R ^Q1 is preferably a linear or branched alkyl group having 1 to 10 carbon atoms, R ^Q2 is preferably a linear or branched alkyl group having 1 to 20 carbon atoms, R ^Q3 is preferably a linear, branched alkyl group, linear alkoxy group or branched alkoxy group having 1 to 8 carbon atoms, and L ^Q is preferably a linear or branched alkylene group having 1 to 8 carbon atoms. In addition, in the compound represented by general formula (Q-c), one or more —CH ₂ — groups in the 1,4-cyclohexylene group may be substituted with oxygen atoms so that they are not directly adjacent to each other.

Among the compounds represented by general formulas (Q-a) to (Q-d), compounds represented by general formulas (Q-c) and (Q-d) are more preferred.

The liquid crystal composition of the present invention preferably contains one or two compounds represented by general formula (Q), more preferably one to five, and the content thereof is preferably 0.001 to 1% by mass, more preferably 0.001 to 0.1% by mass, and particularly preferably 0.001 to 0.05% by mass, relative to 100% by mass of the total amount of liquid crystal compounds contained in the liquid crystal composition.

More specifically, the compounds represented by the following formulas (Q-1) to (Q-34), (Q-37), and (Q-38) are preferred as antioxidants that can be used in the present invention. Furthermore, more specifically, the compounds represented by the following formulas (Q-34) to (Q-36), and (Q-39) to (Q-44) are preferred as light stabilizers that can be used in the present invention. The compound represented by (Q-34) can be used as both an antioxidant and a light stabilizer.

(In the formula, n represents an integer of 0 to 20.)
Among the compounds represented by (Q-1) to (Q-44), the compounds represented by (Q-4) to (Q-6), (Q-21), (Q-22), (Q-35), (Q-39), and (Q-41) are preferred, and the compound represented by (Q-6) is more preferred.

The liquid crystal composition of the present invention preferably contains one or two types of compounds represented by (Q-1) to (Q-44), and more preferably contains one to five types. The content thereof is preferably 0.001 to 1% by mass, more preferably 0.001 to 0.1% by mass, and particularly preferably 0.001 to 0.05% by mass, relative to 100% by mass of the total amount of liquid crystal compounds contained in the liquid crystal composition.

In addition to the above-mentioned compounds, the liquid crystal composition of the present invention may contain ordinary nematic liquid crystals, smectic liquid crystals, cholesteric liquid crystals, ultraviolet absorbers, light stabilizers, infrared absorbers, etc.

Various parameters calculated from the physical properties of a liquid crystal composition are generally used as a method for expressing the characteristics of a liquid crystal display element. In the case of a vertical alignment (VA) liquid crystal display element, a polymer-supported vertical alignment (PSA) or a polymer-stabilized vertical alignment (PSVA), these include _γ1 / _K33 , which is a parameter governing the response speed, _K33 / _K11, which is a parameter governing the steepness of the electro-optic effect, and √| _K33 /Δε|, which is a parameter governing the driving voltage. The liquid crystal composition of the present invention achieves high-speed response, low driving voltage, and high transmittance all at once.

Therefore, γ ₁ /K ₃₃ , which is a parameter governing the response speed, is preferably 9.0 mPa·s·pN ⁻¹ or less, more preferably 8.5 mPa·s·pN ⁻¹ or less, more preferably 8.0 mPa·s·pN ⁻¹ or less, more preferably 7.5 mPa·s·pN ⁻¹ or less, more preferably 7.0 mPa·s·pN ⁻¹ or less, more preferably 6.2 mPa·s·pN ⁻¹ or less, and particularly preferably 6.0 mPa·s·pN ⁻¹ or less.

_K33 / _K11 , which is a parameter that governs the steepness of the electro-optical effect, is preferably 0.80 or more, preferably 0.82 or more, preferably 0.84 or more, preferably 0.86 or more, preferably 0.88 or more, preferably 0.90 or more, preferably 0.92 or more, preferably 0.94 or more, preferably 0.95 or more, and most preferably 0.96 or more.

The parameter governing the driving voltage, √|K ₃₃ /Δε|, is preferably 3.0 pN ^−1/2 or less, preferably 2.8 pN ^−1/2 or less, preferably 2.6 pN ^−1/2 or less, preferably 2.4 pN ^−1/2 or less, preferably 2.3 pN ^−1/2 or less, preferably 2.25 pN ^−1/2 or less, preferably 2.20 pN ^−1/2 or less, and particularly preferably 2.15 pN ^−1/2 or less.

The liquid crystal composition of the present invention is preferably used in a liquid crystal display device in which the polymerizable compound contained therein is polymerized by ultraviolet irradiation to impart liquid crystal alignment ability, and the amount of transmitted light is controlled by utilizing the birefringence of the composition.
<Liquid crystal display element>
A liquid crystal display element using the composition of the present invention is useful because it has no display defects and combines high transmittance, high-speed response, a wide operating temperature range, and good contrast, and is particularly useful as an active matrix drive liquid crystal display element, and can be applied to VA-mode, PSVA-mode, PSA-mode, IPS-mode, FFS-mode, or ECB-mode liquid crystal display elements. In particular, the liquid crystal composition of the present invention is suitable for VA-mode, IPS-mode, and FFS-mode liquid crystal display elements.

The liquid crystal display element of the present invention preferably comprises a first substrate and a second substrate disposed opposite each other, a common electrode provided on the first substrate or the second substrate, pixel electrodes having thin film transistors provided on the first substrate or the second substrate, and a liquid crystal layer containing a liquid crystal composition provided between the first substrate and the second substrate. If necessary, an alignment film for controlling the alignment direction of liquid crystal molecules may be provided on the opposing surface of at least one of the first and/or second substrates so as to abut against the liquid crystal layer. The alignment film may be a vertical alignment film, a horizontal alignment film, or any other suitable film depending on the driving mode of the liquid crystal display element. Known alignment films, such as rubbed alignment films (e.g., polyimide) or photo-aligned films (e.g., decomposable polyimide), can also be used. Furthermore, a color filter may be provided on the first substrate or the second substrate, as appropriate, and a color filter may be provided on the pixel electrode or the common electrode.

The components and manufacturing methods of the liquid crystal display element of the present invention are not particularly limited, and the liquid crystal display element can be constructed and manufactured using general components and manufacturing methods.

When the liquid crystal composition of the present invention contains a polymerizable compound, the method for polymerizing the polymerizable compound is not particularly limited. However, to obtain good alignment performance of the liquid crystal, polymerization at an appropriate polymerization rate is desirable. Therefore, a polymerization method using actinic radiation such as ultraviolet light or electron beams, either singly, in combination, or sequentially, is preferred. When using ultraviolet light, a polarized or unpolarized light source may be used. Furthermore, when polymerizing the liquid crystal composition sandwiched between two substrates, at least the substrate on the irradiated side must be appropriately transparent to actinic radiation. Alternatively, a mask may be used during light irradiation to polymerize only specific portions, and then the alignment state of the unpolymerized portions may be changed by changing conditions such as the electric field, magnetic field, or temperature, and then further irradiating them with actinic radiation to polymerize them. In particular, when exposing to ultraviolet light, it is preferable to expose the liquid crystal composition to ultraviolet light while applying a DC or AC electric field. The applied AC electric field preferably has a frequency of 1 Hz to 10 kHz, more preferably 60 Hz to 10 kHz. The voltage is selected depending on the desired pretilt angle of the liquid crystal display element. In other words, the pretilt angle of the liquid crystal display element can be controlled by the applied voltage. In PSA or PSVA liquid crystal display elements, it is preferable to control the pretilt angle between 80 and 89.9 degrees from the standpoint of alignment stability and contrast.

In PSA or PSVA type liquid crystal display elements, if a polymerizable compound remains unpolymerized after element production, image sticking (IS) occurs. The amount of this remaining polymerizable compound is preferably 100 ppm or less, more preferably 50 ppm or less, more preferably 30 ppm or less, more preferably 20 ppm or less, more preferably 15 ppm or less, particularly preferably 10 ppm or less, and particularly preferably below the lower detection limit or 0.

The temperature during irradiation with active energy rays such as ultraviolet rays or electron beams used to polymerize the polymerizable compound contained in the liquid crystal composition of the present invention is not particularly limited. For example, when the liquid crystal composition of the present invention is applied to a liquid crystal display device equipped with a substrate having an alignment film, the temperature is preferably within a temperature range in which the liquid crystal state of the liquid crystal composition is maintained. In other words, polymerization is preferably carried out at 15 to 50°C.

Lamps that generate ultraviolet light can include metal halide lamps, high-pressure mercury lamps, and ultra-high-pressure mercury lamps. Ushio's ultra-high-pressure UV lamps and Toshiba's fluorescent ultraviolet lamps are preferred, and LED lamps are preferred. The wavelength of the ultraviolet light to be irradiated is preferably within a wavelength range that is not within the absorption wavelength range of the liquid crystal composition, and it is preferable to cut out shorter wavelength ultraviolet light as necessary. The intensity of the irradiated ultraviolet light is preferably 0.1 mW/cm ² to 100 W/cm ² , more preferably 2 mW/cm ² to 50 W/cm ^2. The energy amount of the irradiated ultraviolet light can be adjusted as appropriate, but is preferably 10 mJ/cm ² to 500 J/cm ² , more preferably 100 mJ/cm ² to 200 J/cm ² .

Liquid crystal display elements using the composition of the present invention are useful because they combine high-speed response with reduced display defects, and are particularly useful as active matrix driven liquid crystal display elements, and can be applied to VA mode, PSVA mode, PSA mode, IPS mode, FFS mode, or ECB mode liquid crystal display elements.

Furthermore, in the manufacturing process of liquid crystal display elements using the ODF method, it is necessary to dispense an optimal amount of liquid crystal depending on the size of the liquid crystal display element. However, the liquid crystal composition of the present invention is less affected by, for example, sudden pressure changes and shocks that occur within the dispensing device when dispensing liquid crystal, and it is possible to continue dispensing liquid crystal stably for long periods of time, thereby maintaining a high yield of liquid crystal display elements. In particular, the optimal liquid crystal dispensing amount for the small liquid crystal display elements often used in smartphones, which have become popular recently, is small, making it difficult to control the deviation from the optimal value within a certain range. However, by using the liquid crystal composition of the present invention, a stable amount of liquid crystal material can be dispensed even in small liquid crystal display elements.

The present invention will be described in further detail below with reference to examples, but the present invention is not limited to these examples. Furthermore, in the compositions of the following examples and comparative examples, "%" means "% by mass."

The properties measured in the examples are as follows:

T _ni : Nematic phase-isotropic liquid phase transition temperature (°C)
Δn: refractive index anisotropy at 298K Δε: dielectric anisotropy at 298K γ ₁ : rotational viscosity at 298K (mPa·s)
K ₁₁ : Elastic constant of the splay at 298 K (pN)
_K33 : Elastic constant of bending at 298K (pN)
K _ave : average elastic constant (pN) at 298 K calculated from (K ₃₃ +K ₁₁ )/2
Unless otherwise specified, each physical property value was measured based on the method described in "Japan Electronics and Information Technology Industries Association Standard JEITA ED-2521B (revised March 2009, published by Japan Electronics and Information Technology Industries Association)."
In the examples, the following abbreviations are used to describe compounds.
<Ring structure>

<Side chain structure>

(However, n in the table is a natural number.)
<Connection structure>

(However, n in the table is a natural number.)
<Evaluation of Liquid Crystal Display Element>
To evaluate the properties of horizontally aligned liquid crystal display elements, the prepared liquid crystal compositions were vacuum injected into cells with comb-shaped ITO that had been coated with a polyimide alignment film that induces homogeneous alignment and then rubbed, to obtain FFS liquid crystal display elements. The electro-optical properties of these obtained FFS liquid crystal display elements were measured, and evaluations were made of the driving voltage, response speed, transmittance, contrast, etc.
To evaluate the properties of a vertically aligned liquid crystal display element, the prepared liquid crystal compositions were injected into an ITO cell coated with a polyimide alignment film that induces homeotropic alignment by vacuum injection to obtain a vertically aligned (VA) liquid crystal display element. The electro-optical properties of these obtained VA liquid crystal display elements were measured, and evaluations were made of the driving voltage, response speed, transmittance, contrast, etc.
A) Response speed, transmittance, and driving voltage: The response speed was measured as the time it took for the transmittance to change from 90% to 10% when a predetermined voltage was applied to a VA or FFS liquid crystal display element. The transmittance and driving voltage were measured by measuring the applied voltage-transmittance curve (VT curve) of the VA or FFS liquid crystal display element. With regard to the Examples, a sample was rated as "Good" if it exhibited sufficient performance relative to the required characteristics, and "Poor" if it did not exhibit sufficient performance relative to the required characteristics. With regard to the Comparative Examples, a sample was rated as "Good" if it exhibited sufficient performance comparable to that of the liquid crystal display element obtained in the Examples, and Poor if it was confirmed that the performance was significantly inferior to that of the liquid crystal display element obtained in the Examples.
B) Contrast: The contrast is defined as the amount of light transmitted in the bright state divided by the amount of light transmitted in the dark state when a liquid crystal display element is placed between polarizers set at an appropriate angle and a voltage is applied with a constant backlight turned on. In the present examples, the applied voltage-transmittance curve (VT curve) was measured when a voltage ranging from 0 V to 8.0 V was applied to the prepared FFS liquid crystal display element, and the maximum amount of light transmitted in the VT curve was defined as the amount of light transmitted in the bright state, and the amount of light transmitted when a voltage of 0 V was applied was defined as the amount of light transmitted in the dark state. The contrast of the prepared liquid crystal display element was evaluated by using the contrast of a liquid crystal display element prepared using the liquid crystal composition of the present invention as the standard (◯). If the contrast difference between the liquid crystal display elements prepared using the liquid crystal composition of the corresponding comparative example (Example 1-Comparative Example 1, Example 2-Comparative Example 2, Example 3-Comparative Example 3) was within ±1.0%, the liquid crystal composition of the comparative example was evaluated as ◯. If the contrast difference was greater than 1.0%, the liquid crystal composition of the comparative example was evaluated as x.
C) Low temperature storage stability (LTS): The liquid crystal display element was stored at -30°C for 240 hours, and the presence or absence of display defects such as bright spots was confirmed. No display defects were indicated as O, and display defects were indicated as ×.
Example 1 and Comparative Example 1
Liquid crystal compositions LC-01 (Example 1) and LC-A (Comparative Example 1) were prepared and their physical properties were measured. The constitutions of the liquid crystal compositions and the results of their physical properties are shown below.

It was found that LC-01 is a liquid crystal composition exhibiting electro-optical properties in which γ ₁ /K _ave , which is a parameter that governs response speed, is sufficiently small, √|K _ave /Δε|, which is a parameter that governs drive voltage, is sufficiently low, and K _ave , which strongly governs contrast, is sufficiently large. In other words, the liquid crystal composition of the present invention is a liquid crystal composition that combines high-speed response, high transmittance, low drive voltage, high contrast, and low-temperature storage stability.

On the other hand, LC-A, which does not satisfy the requirements for a liquid crystal compound having a dielectric anisotropy more negative than −2 used in the liquid crystal composition of the present invention, had a larger γ ₁ /K _ave , which is a parameter that governs the response speed, than LC-01, and its LTS was also unacceptable.
Example 2 and Comparative Example 2
Liquid crystal compositions LC-02 (Example 2) and LC-B (Comparative Example 2) were prepared and their physical properties were measured. The constitutions of the liquid crystal compositions and the results of their physical properties are shown below.

It was found that LC-02 is a liquid crystal composition having a sufficiently small γ ₁ /K _ave , which is a parameter that governs the response speed, a sufficiently low √|K _ave /Δε|, which is a parameter that governs the driving voltage, and a sufficiently large K _ave , which strongly governs the contrast. In other words, the liquid crystal composition of the present invention is a liquid crystal composition that combines high-speed response, high transmittance, low driving voltage, high contrast, and low-temperature storage stability.

On the other hand, LC-B, which does not satisfy the requirements for a liquid crystal compound having a dielectric anisotropy more negative than −2 used in the liquid crystal composition of the present invention, had a larger γ ₁ /K _ave , which is a parameter that governs the response speed, than LC-02, and was a liquid crystal composition whose K _ave , which strongly governs the contrast, was lower than that of the present invention.
Example 3 and Comparative Example 3
Liquid crystal compositions LC-03 (Example 3) and LC-C (Comparative Example 3) were prepared and their physical properties were measured. The constitution of the liquid crystal compositions and the results of their physical properties are shown below.

It was found that both LC-03 and LC-C are liquid crystal compositions having a sufficiently small γ ₁ /K _ave , which is a parameter that governs the response speed, a sufficiently low √|K _ave /Δε|, which is a parameter that governs the driving voltage, and a sufficiently large K _ave , which strongly governs the contrast. In other words, the liquid crystal composition of the present invention is a liquid crystal composition that combines high-speed response, high transmittance, low driving voltage, high contrast, and low-temperature storage stability.

However, LC-C, which does not satisfy the requirements for a liquid crystal compound having a dielectric anisotropy more negative than −2 used in the liquid crystal composition of the present invention, had a lower K _ave , which strongly influences the contrast, than the liquid crystal composition of the present invention, and also had poor low-temperature storage stability.
Example 4
A liquid crystal composition of LC-04 (Example 4) was prepared and its physical properties were measured. The constitution of the liquid crystal composition and the results of its physical properties are shown below.

It was found that LC-04 is a liquid crystal composition having a sufficiently small γ ₁ /K _ave , which is a parameter that governs the response speed, a sufficiently low √|K _ave /Δε|, which is a parameter that governs the driving voltage, and a sufficiently large K _ave , which strongly governs the contrast. In other words, the liquid crystal composition of the present invention is a liquid crystal composition that combines high-speed response, high transmittance, low driving voltage, high contrast, and low-temperature storage stability.
<Examples 5 to 8>
Liquid crystal compositions LC-05 (Example 5), LC-06 (Example 6), LC-07 (Example 7), and LC-08 (Example 8) were prepared and their physical properties were measured. The constitutions of the liquid crystal compositions and the results of their physical properties are shown below.

It was found that LC-05 to LC-08 are liquid crystal compositions having a sufficiently small γ ₁ /K _ave , which is a parameter that governs the response speed, a sufficiently low √|K _ave /Δε|, which is a parameter that governs the drive voltage, and a sufficiently large K _ave , which strongly governs the contrast. It was also confirmed that LC-05 to LC-08 are liquid crystal compositions having good low-temperature storage stability.

From the above, it has been found that the liquid crystal composition of the present invention, when used in a liquid crystal display device, combines high-speed response, high transmittance, low driving voltage, high contrast, and low-temperature storage stability.

Claims (5)

The liquid crystal compound having a dielectric anisotropy more negative than −2 contains two or more liquid crystal compounds selected from the following general formula (N1):
(In the formula, A ^N11 and A ^N12 each independently represent
(a) a 1,4-cyclohexylene group (one —CH ₂ — or two or more non-adjacent —CH ₂ — groups in this group may be replaced by —O—), and (b) a 1,4-phenylene group (one —CH= or two or more non-adjacent —CH= groups in this group may be replaced by —N=).
(c) a naphthalene-2,6-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, or a decahydronaphthalene-2,6-diyl group (one —CH= or two or more non-adjacent —CH= groups in the naphthalene-2,6-diyl group or the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced by —N=).
(d) a group selected from the group consisting of 1,4-cyclohexenylene groups, wherein the groups (a), (b), (c), and (d) may each independently be substituted with a cyano group, a fluorine atom, or a chlorine atom;
Z ^N11 and Z ^N12 each independently represent a single bond, —CH ₂ CH ₂ —, —(CH ₂ ) ₄ —, —OCH ₂ —, —CH ₂ O—, —COO—, —OCO—, —OCF ₂ —, —CF ₂ O—, —CH═N—N═CH—, —CH═CH—, —CF═CF— or —C≡C—;
^nN11 and ^nN12 each independently represent 0 or 1, provided that ^nN11 + ^nN12 is 1 or 2.
the total content of the liquid crystal compounds represented by general formula (N1) is 75 mass % or more of the total content of liquid crystal compounds having a dielectric anisotropy more negative than −2, which are used in the liquid crystal composition,
Contains a liquid crystal compound represented by formula (L-10-1),
The liquid crystal compound selected from the general formula (N1) contains two or more liquid crystal compounds selected from the following general formulas (N1-I) to (N1-VI):
Further, the liquid crystal compound represented by formula (L-10-2) is contained,
Furthermore, the composition contains one or more compounds represented by general formula (L),
(wherein R ^L1 and R ^L2 each independently represent an alkyl group having 1 to 8 carbon atoms, and one or two or more non-adjacent —CH ₂ — groups in the alkyl group may each independently be replaced by —CH═CH—, —C≡C—, —O—, —CO—, —COO— or —OCO—;
n ^L1 represents 0, 1, 2 or 3;
A ^L1 , A ^L2 and A ^L3 each independently represent (a) a 1,4-cyclohexylene group (in which one —CH ₂ — or two or more non-adjacent —CH ₂ — groups may be replaced with —O—), and (b) a 1,4-phenylene group (in which one —CH= or two or more non-adjacent —CH= groups may be replaced with —N=).
(c) a naphthalene-2,6-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, or a decahydronaphthalene-2,6-diyl group (one —CH= or two or more non-adjacent —CH= groups in the naphthalene-2,6-diyl group or the 1,2,3,4-tetrahydronaphthalene-2,6-diyl group may be replaced by —N=).
wherein the groups (a), (b) and (c) may each independently be substituted with a cyano group, a fluorine atom or a chlorine atom;
Z ^L1 and Z ^L2 each independently represent a single bond, —CH ₂ CH ₂ —, —(CH ₂ ) ₄ —, —OCH ₂ —, —CH ₂ O—, —COO—, —OCO—, —OCF ₂ —, —CF ₂ O—, —CH═N—N═CH—, —CH═CH—, —CF═CF— or —C≡C—;
When n ^L1 is 2 or 3 and a plurality of A ^L2s are present, they may be the same or different, and when n ^L1 is 2 or 3 and a plurality of Z ^L2s are present, they may be the same or different , except for the compounds represented by formula (L-10-1) and formula (L-10-2).
A liquid crystal composition, wherein the contents of the liquid crystal compounds represented by general formulas (N1-I) to (N1-VI) are, based on the weight of the liquid crystal composition, 12 to 20% by weight of the liquid crystal compound represented by general formula (N1-I), 10 to 22% by weight of the liquid crystal compound represented by general formula (N1-II), 8 to 18% by weight of the liquid crystal compound represented by general formula (N1-III), 8 to 20% by weight of the liquid crystal compound represented by general formula (N1-IV), 7 to 15% by weight of the liquid crystal compound represented by general formula (N1-V), and 3 to 15% by weight of the liquid crystal compound represented by general formula (N1-VI). The liquid crystal composition according to claim 1, further comprising one or more additives selected from the group consisting of antioxidants, light stabilizers, ultraviolet absorbers, and infrared absorbers. The liquid crystal composition according to claim 1 , further comprising a polymerizable compound represented by general formula (P):
(In the above general formula (P), R ^p1 represents a hydrogen atom, a fluorine atom, a cyano group, an alkyl group having 1 to 15 carbon atoms, or -Sp ^p2 -P ^p2 , one or two or more non-adjacent -CH ₂ - groups in the alkyl group may each independently be substituted with -CH═CH-, -C≡C-, -O-, -CO-, -COO-, or -OCO-, and one or two or more hydrogen atoms in the alkyl group may each independently be substituted with a cyano group, a fluorine atom, or a chlorine atom;
P ^p1 and P ^p2 each independently represent a group represented by the general formula (P ^p1 -1) to the formula (P ^p1 -9):
(In the formula, R ^p11 and R ^p12 each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogenated alkyl group having 1 to 5 carbon atoms; W ^p11 represents a single bond, —O—, —COO—, or a methylene group; and t ^p11 represents 0, 1, or 2; however, when a plurality of R ^p11 , R ^p12 , W ^p11 , and/or t ^p11 are present in a molecule, they may be the same or different.)
represents one of the following:
Sp ^p1 and Sp ^p2 each independently represent a single bond or a spacer group;
Z ^p1 and Z ^p2 each independently represent a single bond, —O—, —S—, —CH 2 —, —OCH ₂ —, —CH ₂ O—, —CO—, —C _{2 H 4 —} , —COO—, —OCO— _, —OCOOCH ₂ —, —CH ₂ OCOO—, —OCH ₂ CH ₂ O—, —CO—NR ^ZP1 —, —NR ^ZP1 —CO—, —SCH ₂ —, —CH ₂ S—, —CH═CR ^ZP1 —COO—, —CH═CR ZP1 —OCO—, —COO-CR ZP1 ═CH—, —OCO-CR ^ZP1 ═CH—, —COO-CR ^ZP1 ═CH—COO—, —COO-CR ^{ZP1 ═CH} —COO—, —COO-CR ^ZP1 ═CH—OCO—, —OCO—CR ^ZP1 ═CH—COO—, —OCO—CR ^ZP1 ═CH—OCO—, —(CH ₂ ) _z -COO—, —(CH 2 ) ₂ -OCO—, —OCO—(CH ₂ ) ₂ —, —(C═O)—O—(CH ₂ ) ₂ —, —CH═CH—, —CF═CF—, —CF═CH—, —CH═CF—, —CF ₂ —, —CF ₂ O—, —OCF ₂ —, —CF ₂ CH ₂ —, —CH ₂ CF ₂ —, —CF ₂ CF ₂ —, or —C≡C— (wherein R ^ZP1 each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, but if _R When a plurality of ^ZP1s are present, they may be the same or different.
represents
A ^p1 , A ^p2 , and A ^p3 each independently represent
(a ^p ) a 1,4-cyclohexylene group (in which one —CH ₂ — or two or more non-adjacent —CH ₂ — groups may be replaced by —O—).
(b ^p ) a 1,4-phenylene group (one —CH= or two or more non-adjacent —CH= groups in this group may be replaced by —N=), and (c ^p ) a naphthalene-2,6-diyl group, a naphthalene-1,4-diyl group, a 1,2,3,4-tetrahydronaphthalene-2,6-diyl group, a decahydronaphthalene-2,6-diyl group, a phenanthrene-2,7-diyl group, or an anthracene-2,6-diyl group (one —CH= or two or more non-adjacent —CH= groups in these groups may be replaced by —N=).
one or more hydrogen atoms present in the above groups (a ^p ), (b ^p ) and (c ^p ) may each independently be substituted with a halogen atom, a cyano group, an alkyl group having 1 to 8 carbon atoms or -Sp ^p2 -P ^p2 , and one or two or more non-adjacent -CH ₂ - groups in the alkyl group may each independently be substituted with -CH═CH-, -C≡C-, -O-, -CO-, -COO- or -OCO-;
m ^p1 represents 0, 1, 2 or 3, and when a plurality of Z ^p1 , A ^p2 , Sp ^p2 and/or P ^p2 are present in a molecule, they may be the same or different, but A ^p3 represents a single bond when m ^p1 is 0 and A ^p1 is a phenanthrene-2,7-diyl group or an anthracene-2,6-diyl group. A liquid crystal display element using the liquid crystal composition described in any one of claims 1 to 3. A liquid crystal display device using the liquid crystal composition according to any one of claims 1 to 3 in an FFS mode or IP mode
S-mode LCD display element.