JP2021088704A - Liquid crystal composition for use in phase control of electromagnetic wave signal - Google Patents

Abstract

To provide a liquid crystal composition for phase control of an electromagnetic wave signal excellent in optical anisotropy, dielectric loss tangent, and the like.SOLUTION: The liquid crystal composition contains compounds represented by formulas (1), (2) and (3).SELECTED DRAWING: None

Description

The present invention relates to an element used for phase control of an electromagnetic wave signal having a frequency of 1 GHz to 10 THz and a liquid crystal composition used for this element. This composition has a nematic phase and positive permittivity anisotropy.

Examples of the element used for phase control of an electromagnetic wave signal having a frequency of 1 GHz to 10 THz include a millimeter wave band, a microwave band antenna, an infrared laser element, and the like. Various methods have been studied for these elements, but a method using a liquid crystal, which is considered to have few failures because there is no mechanical moving part, is attracting attention.

A liquid crystal composition having dielectric anisotropy is perpendicular and horizontal to the orientation direction of the liquid crystal composition at a frequency (several hundred kHz to several hundred MHz or less) lower than the frequency at which the orientation polarization is relaxed (relaxation frequency). The permittivity in the direction is different.
Even at frequencies higher than the relaxation frequency, the value becomes smaller, but there is a difference in permittivity between the vertical direction and the horizontal direction with respect to the orientation direction of the liquid crystal composition, and it is almost in the range of microwave to terahertz wave (10 THz). It is constant (Non-Patent Document 1). Therefore, the liquid crystal composition can change the dielectric constant in one direction by changing the orientation direction of the molecules according to the external field.

By utilizing this property, the liquid crystal composition can change the orientation of the molecules according to the bias electric field from the outside and change the dielectric constant. For example, it becomes possible to realize a microwave device capable of electrically controlling the transmission characteristics of a high-frequency transmission line from the outside. Such devices include voltage-controlled millimeter-wave band variable phase shifters in which a waveguide is filled with a nematic liquid crystal composition, and microwave / millimeter-wave bands using a nematic liquid crystal composition as a dielectric substrate for a microstrip line. Wideband variable phase shifters and the like have been reported (Patent Documents 1 and 2).

It is desirable that the element used for the phase control of such an electromagnetic wave signal has characteristics such as high gain and low loss. Therefore, the characteristics required for the liquid crystal composition are proportional to the large dielectric anisotropy that enables wide phase control in the frequency domain used for phase control and the absorbed energy of the electromagnetic wave signal of the liquid crystal composition. It is required that the dielectric anisotropy (tan δ) is small (Non-Patent Document 1).

In addition, the element used for phase control of the electromagnetic wave signal is required to have a wide usable temperature range and a short response time of the element, and the characteristics of the liquid crystal composition include a high upper limit temperature of the nematic phase. Low lower limit temperature of nematic phase, stability against heat, low viscosity, etc. are also required.

Conventional liquid crystal compositions used in the device are disclosed in Patent Documents 3 and 4 below.

International Release 2017/201515 Published in the United States 2018/02239213 Japanese Unexamined Patent Publication No. 2004-285805 JP 2011-74074

EKISHO, Vol. 23 (No. 1), (2019), Paragraphs 51-55

An object of the present invention is to provide a liquid crystal composition having good characteristic requirements and an excellent balance of characteristics as described above as a material used for an element used for phase control of an electromagnetic wave signal having a frequency of 1 GHz to 10 THz. That is.

式（１）、式（２）、および式（３）における各記号の定義は後述する。
As a result of diligent studies, the inventors have found that a liquid crystal composition containing a liquid crystal compound having a specific structure solves the above-mentioned problems, and have completed the present invention. At least one compound selected from the group of compounds represented by the formula (1) as the first component, and at least one selected from the group of compounds represented by the formula (2) as the second component. For phase control of an electromagnetic wave signal having a frequency of any frequency of 1 GHz to 10 THz, which comprises at least one compound selected from the group of compounds represented by the formula (3) as a compound and a third component. The liquid crystal composition used.

The definitions of the symbols in the equations (1), (2), and (3) will be described later.

The compositions of the present invention have a high upper limit temperature of the nematic phase, a lower lower limit temperature of the nematic phase, a large refractive index anisotropy in the frequency domain used for phase control, a large dielectric anisotropy, and a small dielectric loss tangent (tan δ). ), And has heat stability. Therefore, the device using this material has practically excellent characteristics.

The usage of terms in this specification is as follows. The terms "liquid crystal composition" and "liquid crystal display element" may be abbreviated as "composition" and "element", respectively. "Liquid crystal display element" is a general term for a liquid crystal display panel and a liquid crystal display module. A "liquid crystal compound" is a compound having a liquid crystal phase such as a nematic phase or a smectic phase and a compound having no liquid crystal phase, but for the purpose of adjusting properties such as temperature range, viscosity, and dielectric constant anisotropy of the nematic phase. It is a general term for compounds mixed in a composition. This compound has a six-membered ring such as 1,4-cyclohexylene and 1,4-phenylene, and its molecule (liquid crystal molecule) is rod-like. The "polymerizable compound" is a compound added for the purpose of forming a polymer in the composition. Liquid crystal compounds having alkenyl are not classified as polymerizable compounds in that sense.

The liquid crystal composition is prepared by mixing a plurality of liquid crystal compounds. Additives such as optically active compounds and polymerizable compounds are added to the liquid crystal composition as needed. The proportion of the liquid crystal compound is expressed as a mass percentage (mass%) based on the mass of the liquid crystal composition containing no additive even when the additive is added. The ratio of the additive is expressed as a mass percentage (mass%) based on the mass of the liquid crystal composition containing no additive. That is, the ratio of the liquid crystal compound or the additive is calculated based on the total mass of the liquid crystal compound.

The "upper limit temperature of the nematic phase" may be abbreviated as the "upper limit temperature". The "lower limit temperature of the nematic phase" may be abbreviated as the "lower limit temperature". The expression "increase the dielectric anisotropy" means that when the composition has a positive dielectric anisotropy, its value increases positively, and the composition has a negative dielectric anisotropy. When it is a thing, it means that its value increases negatively.

上記の化合物（１ｚ）を例にして説明する。式（１ｚ）において、六角形で囲んだαおよびβの記号はそれぞれ環αおよび環βに対応し、六員環、縮合環のような環を表す。添え字‘ｘ’が２のとき、２つの環αが存在する。２つの環αが表す２つの基は、同一であってもよく、または異なってもよい。このルールは、添え字‘ｘ’が２より大きいとき、任意の２つの環αに適用される。このルールは、結合基Ｚのような、他の記号にも適用される。環βの一辺を横切る斜線は、環β上の任意の水素が置換基（−Ｓｐ−Ｐ）で置き換えられてもよいことを表す。添え字‘ｙ’は置き換えられた置換基の数を示す。添え字‘ｙ’が０のとき、そのような置き換えはない。添え字‘ｙ’が２以上のとき、環β上には複数の置換基（−Ｓｐ−Ｐ）が存在する。この場合にも、「同一であってもよく、または異なってもよい」のルールが適用される。なお、このルールは、Ｒａの記号を複数の化合物に用いた場合にも適用される。

The above compound (1z) will be described as an example. In formula (1z), the symbols α and β enclosed in hexagons correspond to rings α and ring β, respectively, and represent rings such as a six-membered ring and a condensed ring. When the subscript'x' is 2, there are two rings α. The two groups represented by the two rings α may be the same or different. This rule applies to any two rings α when the subscript'x' is greater than 2. This rule also applies to other symbols, such as binding group Z. A diagonal line across one side of the ring β indicates that any hydrogen on the ring β may be replaced by a substituent (-Sp-P). The subscript'y'indicates the number of substituents replaced. When the subscript'y'is 0, there is no such replacement. When the subscript'y'is 2 or more, a plurality of substituents (-Sp-P) are present on the ring β. In this case as well, the rule of "may be the same or different" applies. This rule also applies when the Ra symbol is used for a plurality of compounds.

In formula (1z), for example, expressions such as "Ra and Rb are alkyl, alkoxy, or alkenyl" are such that Ra and Rb are independently selected from the group of alkyl, alkoxy, and alkenyl. Means. Here, the group represented by Ra and the group represented by Rb may be the same or different. This rule also applies when the Ra symbol is used for multiple compounds. This rule also applies when multiple Ras are used in one compound.

At least one compound selected from the compounds represented by the formula (1z) may be abbreviated as "Compound (1z)". "Compound (1z)" means one compound represented by the formula (1z), a mixture of two compounds, or a mixture of three or more compounds. The same applies to compounds represented by other formulas. The expression "at least one compound selected from the compounds of formula (1z) and formula (2z)" means at least one compound selected from the group of compounds (1z) and compound (2z). ..

The expression "at least one'A'" means that the number of'A's is arbitrary. The expression "at least one'A'may be replaced by'B'" is that when the number of'A's is 1, the position of the'A'is arbitrary and the number of'A's is 2. When there is more than one, their positions can be selected without limitation. The expression "at least one -CH _2- may be replaced by -O-" may be used. In this case, −CH ₂ −CH ₂ −CH ₂₋ may be converted to −O−CH ₂₋ O− by replacing the non-adjacent −CH _{2− with −O−.} However, the adjacent −CH ₂₋ is not replaced by −O−. This is because -O-O-CH _2- (peroxide) is produced by this replacement.

テトラヒドロピラン−２，５−ジイルのような二価基においても同様である。なお、好ましいテトラヒドロピラン−２，５−ジイルは、上限温度を上げるために右向き（Ｒ）である。カルボニルオキシのような結合基（−ＣＯＯ−または−ＯＣＯ−）も同様である。 The alkyl of the liquid crystal compound is a straight chain or a branched chain and does not contain a cyclic alkyl. Straight chain alkyls are preferred over branched chain alkyls. The same applies to terminal groups such as alkoxy and alkenyl. The configuration for 1,4-cyclohexylene is preferably trans over cis in order to raise the upper temperature limit. Since 2-fluoro-1,4-phenylene is asymmetrical, there are leftward (L) and rightward (R).

The same is true for divalent groups such as tetrahydropyran-2,5-diyl. The preferred tetrahydropyran-2,5-diyl is rightward (R) in order to raise the upper limit temperature. The same is true for binding groups such as carbonyloxy (-COO- or -OCO-).

The present invention includes the following items.

式（１）、式（２）、および式（３）において、Ｒ^１ａ、Ｒ^１ｂ、Ｒ^２ａ、およびＲ^２ｂは、炭素数１から２０のアルキル、炭素数１から２０のアルコキシ、炭素数２から２０のアルケニル、または炭素数２から２０のアルケニルオキシであり；Ｒ^３ａは、炭素数１から２０のアルキルまたは炭素数２から２０のアルケニルであり；環Ａ^１ａ、環Ａ^２ａ、および環Ａ^２ｂは、１，４−フェニレン、２−フルオロ−１，４−フェニレン、２，３−ジフルオロ−１，４−フェニレン、２，５−ジフルオロ−１，４−フェニレン、２，６−ジフルオロ−１，４−フェニレンであり；環Ａ^３ａは、１，４−シクロへキシレン、ピリジン−２，５−ジイル、ピリミジン−２，５−ジイル、１，３−ジオキサン−２，５−ジイル、またはテトラヒドロピラン−２，５−ジイルであり；環Ａ^３ｂ、環Ａ^３ｃおよび環Ａ^３ｄは、１，４−シクロへキシレン、１，４−フェニレン、２−フルオロ−１，４−フェニレン、２，５−ジフルオロ−１，４−フェニレン、２，６−ジフルオロ−１，４−フェニレン、ピリジン−２，５−ジイル、ピリミジン−２，５−ジイル、１，３−ジオキサン−２，５−ジイル、またはテトラヒドロピラン−２，５−ジイルであり；Ｚ^３ａ、Ｚ^３ｂ、Ｚ^３ｃおよびＺ^３ｄは、単結合、カルボニルオキシまたはジフルオロメチレンオキシであり；
Ｘ^３ａ、Ｘ^３ｂ、およびＸ^３ｃは、水素またはフッ素であるが、Ｘ^３ａおよびＸ^３ｂが同時にフッ素であることはなく；Ｙ^３ａは、−ＣＮ、−ＮＣＳ、フッ素、塩素、少なくとも１つの水素がハロゲンで置き換えられてもよい炭素数１から１２のアルキル、少なくとも１つの水素がハロゲンで置き換えられてもよい炭素数１から１２のアルコキシ、または少なくとも１つの水素がハロゲンで置き換えられてもよい炭素数２から１２のアルケニルであり；ｎ^１ａは１または２であり；ｎ^３ａおよびｎ^３ｂは、０または１であり、ｎ^３ａが０、ｎ^３ｂが１である場合、Ｚ^３ｃはジフルオロメチレンオキシである。 Item 1. At least one compound selected from the group of compounds represented by the formula (1) as the first component, and at least one compound selected from the group of compounds represented by the formula (2) as the second component. A liquid crystal composition used for phase control of an electromagnetic wave signal having a frequency of 1 GHz to 10 THz, which contains at least one compound selected from the group of compounds represented by the formula (3) as a third component. ..

In formulas (1), (2), and (3), R ^1a , R ^1b , R ^2a , and R ^2b are alkyl having 1 to 20 carbon atoms, alkoxy having 1 to 20 carbon atoms, and 2 carbon atoms. To 20 alkenyl, or 2 to 20 carbon alkenyloxy; R ^3a is an alkyl 1 to 20 carbon or an alkenyl 2 to 20 carbon; ring A ^1a , ring A ^2a , and ring A. ^2b is 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,5-difluoro-1,4-phenylene, 2,6-difluoro-1. , 4-Phenylene; ring ^A3a is 1,4-cyclohexylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydro. It is pyran-2,5-diyl; ring A ^3b , ring A ^3c and ring A ^3d are 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,5. -Difluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, or Tetrahydropyrene-2,5-diyl; Z ^3a , Z ^3b , Z ^3c and Z ^3d are single-bonded, carbonyloxy or difluoromethyleneoxy;
X ^3a , X ^3b , and X ^3c are hydrogen or fluorine, but X ^3a and X ^3b are not fluorine at the same time; Y ^3a is -CN, -NCS, fluorine, chlorine, at least one hydrogen. Is an alkyl having 1 to 12 carbon atoms which may be replaced by a halogen, an alkoxy having 1 to 12 carbon atoms which may be replaced by a halogen at least one hydrogen, or a carbon which may be replaced by a halogen at least one hydrogen. The numbers 2 to 12 are alkenyl; n ^1a is 1 or 2; n ^3a and n ^3b are 0 or 1, n ^3a is 0, n ^3b is 1, Z ^3c is difluoromethyleneoxy. Is.

これらの式においてＲ^１ａおよびＲ^１ｂは、炭素数１から２０のアルキル、炭素数１から２０のアルコキシ、炭素数２から２０のアルケニル、または炭素数２から２０のアルケニルオキシである。 Item 2. Item 2. The liquid crystal composition according to Item 1, which contains at least one compound selected from the compounds represented by the formulas (1-1) to (1-9) as the first component.

In these formulas, R ^1a and R ^1b are alkyls having 1 to 20 carbon atoms, alkoxy having 1 to 20 carbon atoms, alkenyl having 2 to 20 carbon atoms, or alkenyloxy having 2 to 20 carbon atoms.

Item 3. Item 2. The liquid crystal composition according to Item 1 or 2, wherein the ratio of the first component is in the range of 3% by mass to 80% by mass based on the mass of the liquid crystal composition.

これらの式においてＲ^２ａおよびＲ^２ｂは、炭素数１から２０のアルキル、炭素数１から２０のアルコキシ、炭素数２から２０のアルケニル、または炭素数２から２０のアルケニルオキシである。 Item 4. Item 6. The liquid crystal composition according to any one of Items 1 to 3, which contains at least one compound selected from the compounds represented by the formulas (2-1) to (2-4) as the second component. ..

In these formulas, R ^2a and R ^2b are alkyls having 1 to 20 carbon atoms, alkoxys having 1 to 20 carbon atoms, alkenyl having 2 to 20 carbon atoms, or alkenyloxy having 2 to 20 carbon atoms.

Item 5. Item 2. The liquid crystal composition according to any one of Items 1 to 4, wherein the ratio of the second component is in the range of 3% by mass to 40% by mass based on the mass of the liquid crystal composition.

これらの式において、Ｒ^３ａは、炭素数１から２０のアルキルまたは、炭素数２から２０のアルケニルである。 Item 6. Item 2. The liquid crystal composition according to any one of Items 1 to 5, which contains at least one compound selected from the compounds represented by the formulas (3-1) to (3-41) as the third component. ..

In these formulas, R ^3a is an alkyl having 1 to 20 carbon atoms or an alkenyl having 2 to 20 carbon atoms.

Item 7. Item 1 to any one of Items 1 to 5 ^{, wherein Z 3a} , Z ^3b , Z ^3c and Z ^3d are all single bonds in all the compounds represented by the formula (3) according to claim 1 as the third component. The liquid crystal composition according to.

Item 8. Item 2. The liquid crystal composition according to any one of Items 1 to 7, wherein the ratio of the third component is in the range of 3% by mass to 50% by mass based on the mass of the liquid crystal composition.

式（４）において、Ｒ^４ａおよびＲ^４ｂは、炭素数１から１２のアルキル、炭素数１から１２のアルコキシ、炭素数２から１２のアルケニル、または少なくとも１つの水素がフッ素または塩素で置き換えられた炭素数２から１２のアルケニルであり；環Ａおよび環Ｂは、１，４−シクロヘキシレン、１，４−フェニレン、２−フルオロ−１，４−フェニレン、２，３−ジフルオロ−１，４−フェニレン、２，５−ジフルオロ−１，４−フェニレンまたは、２，６−ジフルオロ−１，４−フェニレンであり；Ｚ^４ａは、エチレン、ビニレン、エチニレン、メチレンオキシ、またはカルボニルオキシであり；ａは、１、２、または３であり；ａが２または３の時、複数存在する環ＡおよびＺ^４ａは、同じであっても異なっていてもよく、Ｚ^４ａのいずれかは単結合でもよいが、Ｚ^４ａの全てが同時に単結合であることはない。 Item 9. Item 8. The liquid crystal composition according to any one of Items 1 to 8, further containing at least one compound selected from the compounds represented by the formula (4) as the fourth component.

In formula (4), R ^4a and R ^4b have an alkyl having 1 to 12 carbon atoms, an alkoxy having 1 to 12 carbon atoms, an alkenyl having 2 to 12 carbon atoms, or at least one hydrogen being replaced with fluorine or chlorine. It is an alkoxy having 2 to 12 carbon atoms; rings A and B are 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-. Phenylene, 2,5-difluoro-1,4-phenylene or 2,6-difluoro-1,4-phenylene; Z ^4a is ethylene, vinylene, ethynylene, methyleneoxy, or carbonyloxy; a is 1, 2, or 3; when a is 2 or 3, the plurality of rings A and Z ^4a may be the same or different, and ^{any of Z 4a} may be a single bond. , Z ^4a are not all single bonds at the same time.

Ｒ^４ａおよびＲ^４ｂは、炭素数１から１２のアルキル、炭素数１から１２のアルコキシ、炭素数２から１２のアルケニル、または少なくとも１つの水素がフッ素または塩素で置き換えられた炭素数２から１２のアルケニルである。 Item 10. Item 9. The liquid crystal composition according to Item 9, which contains at least one compound selected from the compounds represented by the formulas (4-1) to (4-20) as the fourth component.

R ^4a and R ^4b are alkyls with 1 to 12 carbon atoms, alkoxys with 1 to 12 carbon atoms, alkenyl with 2 to 12 carbon atoms, or 2 to 12 carbon atoms in which at least one hydrogen is replaced with fluorine or chlorine. It is alkenyl.

Item 11. Item 9. The liquid crystal composition according to Item 9 or 10, wherein the ratio of the fourth component is in the range of 3% by mass to 80% by mass based on the mass of the liquid crystal composition.

Item 12. Item 2. The liquid crystal composition according to any one of Items 1 to 11, wherein the refractive index anisotropy at 25 ° C. at a wavelength of 589 nm is 0.20 to 0.80.

Item 2. The liquid crystal composition according to any one of Items 1 to 11, wherein the dielectric anisotropy at 25 ° C. at any frequency from 13.1 GHz to 10 THz is in the range of 0.40 to 2.0.

Item 14. Item 6. The liquid crystal composition according to any one of Items 1 to 13, which contains an optically active compound.

Item 15. Item 6. The liquid crystal composition according to any one of Items 1 to 13, which contains a polymerizable compound.

Item 16. An element used for phase control of an electromagnetic wave signal having a frequency of any one of 1 GHz to 10 THz, which contains the liquid crystal composition according to any one of Items 1 to 15.

The present invention also includes the following sections. (A) One compound selected from additives such as optically active compounds, antioxidants, ultraviolet absorbers, small steel materials, dyes, general foaming agents, polymerizable compounds, polymerization initiators, polymerization inhibitors, polar compounds. The above composition containing two compounds, or three or more compounds. (B) AM device containing the above composition. (C) The above composition further containing a polymerizable compound, and a polymer-supported orientation (PSA) type AM device containing this composition. (D) A device containing the above composition and having a mode of PC, TN, STN, ECB, OCB, IPS, VA, FFS, or FPA. (E) A transmissive device containing the above composition. (F) Use of the above composition as a composition having a nematic phase. (G) Use of an optically active composition obtained by adding an optically active compound to the above composition.

Such a composition has a large refractive index anisotropy, a large dielectric anisotropy, and a small dielectric loss tangent (tan δ) in the frequency domain of an electromagnetic wave signal of 1 GHz to 10 THz. The composition of the present invention controls an element related to an electromagnetic wave frequency between the dielectric relaxation frequency and the ionic polarization frequency, that is, 1 GHz to 10 THz, and further 1 GHz to 50 GHz, in which the variation in the dielectric constant is small and the loss of the electromagnetic wave is small. It is preferable to use it for various purposes.

The composition of the present invention will be described in the following order. First, the composition of the composition will be described. Secondly, the main properties of the component compound and the main effect of this compound on the composition and the device will be described. Thirdly, the combination of the component compounds in the composition, the preferable ratio, and the rationale thereof will be described. Fourth, preferable forms of the component compounds will be described. Fifth, preferred component compounds are shown. Sixth, additives that may be added to the composition will be described. Seventh, a method for synthesizing a component compound will be described. Finally, the use of the composition will be described.

First, the composition of the composition will be described. This composition contains a plurality of liquid crystal compounds. This composition may contain additives. Additives include optically active compounds, antioxidants, UV absorbers, light extinguishing agents, dyes, defoamers, polymerizable compounds, polymerization initiators, polymerization inhibitors, polar compounds and the like. This composition is classified into the composition (a) and the composition (b) from the viewpoint of the liquid crystal compound. The composition (a) further contains other liquid crystal compounds, additives and the like in addition to the liquid crystal compound selected from the compound (1), the compound (2), the compound (3) and the compound (4). You may. The "other liquid crystal compound" is a liquid crystal compound different from the compound (1), the compound (2), the compound (3) and the compound (4). Such compounds are mixed into the composition for the purpose of further adjusting the properties.

The composition (b) is substantially composed of only a liquid crystal compound selected from the compound (1), the compound (2), the compound (3) and the compound (4). "Substantially" means that the composition (b) may contain additives but does not contain other liquid crystal compounds. The composition (b) has a smaller number of components than the composition (a). The composition (b) is preferable to the composition (a) from the viewpoint of reducing the cost. The composition (a) is preferable to the composition (b) from the viewpoint that the properties can be further adjusted by mixing other liquid crystal compounds.

Secondly, the main properties of the component compound and the main effect of this compound on the composition and the device will be described. The main properties of the constituent compounds are summarized in Table 1 based on the effects of the present invention. In the symbols in Table 1, L means large or high, M means medium, and S means small or low. The symbols L, M and S are classifications based on qualitative comparisons between the constituent compounds, and the symbol 0 (zero) means less than S.

Table 1 Characteristics of liquid crystal compounds

The main effects of the component compounds are as follows. Compound (1) lowers the viscosity and lowers the lower limit temperature. It does not affect the dielectric anisotropy. Compound (2) increases the refractive index anisotropy. Raise the upper limit temperature. It does not affect the dielectric anisotropy. Compound (3) increases the dielectric anisotropy. Compound (4) lowers the viscosity and lowers the lower limit temperature. Increase the refractive index anisotropy. It does not affect the dielectric anisotropy.

Thirdly, the combination of components in the composition, the preferable ratio of the component compounds, and the rationale thereof will be described. A preferred combination of components in the composition is compound (1) + compound (2) + compound (3) or compound (1) + compound (2) + compound (3) + compound (4). A more preferred combination is compound (1) + compound (2) + compound (3) + compound (4).

The preferred proportion of compound (1) is in the range of about 3% by weight to about 80% by weight in order to lower the lower limit temperature or lower the viscosity. A more preferable ratio is in the range of about 20% by mass to about 75% by mass. A particularly preferable ratio is in the range of about 15% by mass to about 70% by mass.

A preferred proportion of compound (2) increases the refractive index anisotropy. It is in the range of about 3% by mass to about 40% by mass in order to raise the upper limit temperature. A more preferable ratio is in the range of about 3% by mass to about 35% by mass. A particularly preferable ratio is in the range of about 3% by mass to about 30% by mass.

The preferred proportion of compound (3) is in the range of about 3% by mass to about 50% by mass in order to increase the dielectric anisotropy. A more preferable ratio is in the range of about 5% by mass to about 40% by mass. A particularly preferable ratio is in the range of about 10% by mass to about 35% by mass.

A preferred proportion of compound (4) is to lower the viscosity, lower the lower limit temperature. The range is from about 3% by mass to about 80% by mass in order to increase the refractive index anisotropy. A more preferable ratio is in the range of about 5% by mass to about 70% by mass. A particularly preferable ratio is in the range of about 10% by mass to about 60% by mass.

Fourth, preferable forms of the component compounds will be described. In formulas (1), (2), (3) and (4), R ^1a , R ^1b , R ^2a , and R ^2b are alkyl having 1 to 20 carbon atoms and alkoxy having 1 to 20 carbon atoms. , Alkoxy having 2 to 20 carbon atoms, or Alkoxyoxy having 2 to 20 carbon atoms. Preferred R ^1a , R ^1b , R ^2a , and R ^2b are alkyl having 1 to 20 carbon atoms for increased stability to light or heat.

R ^3a is an alkyl having 1 to 20 carbon atoms or an alkenyl having 2 to 20 carbon atoms. Preferred ^R3a is an alkyl having 1 to 20 carbon atoms for increased stability to light or heat.

R ^4a and R ^4b are alkyls with 1 to 12 carbon atoms, alkoxys with 1 to 12 carbon atoms, alkenyl with 2 to 12 carbon atoms, or 2 to 12 carbon atoms in which at least one hydrogen is replaced with fluorine or chlorine. It is alkenyl. Preferred R ^4a or R ^4b are alkenyl with 2 to 12 carbons to reduce viscosity and alkyl with 1 to 12 carbons to increase stability to light or heat.

Preferred alkyls are methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, or octyl. More preferred alkyls are methyl, ethyl, propyl, butyl, or pentyl to reduce viscosity.

Preferred alkoxys are methoxy, ethoxy, propoxy, butoxy, pentyloxy, hexyloxy, or heptyloxy. More preferred alkoxys are methoxy or ethoxy to reduce the viscosity.

Preferred alkenyl is vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, or 5-hexenyl. More preferred alkenyl is vinyl, 1-propenyl, 3-butenyl, or 3-pentenyl to reduce the viscosity. The preferred configuration of -CH = CH- in these alkenyl depends on the position of the double bond. Trans is preferable in alkenyl such as 1-propenyl, 1-butenyl, 1-pentenyl, 1-hexenyl, 3-pentenyl, 3-hexenyl for the purpose of lowering the viscosity. Sis is preferred for alkenyl such as 2-butenyl, 2-pentenyl, 2-hexenyl.

Preferred alkenyloxys are vinyloxy, allyloxy, 3-butenyloxy, 3-pentenyloxy, or 4-pentenyloxy. More preferred alkenyloxy to reduce viscosity are allyloxy or 3-butenyloxy.

Ring A ^1a , Ring A ^2a , and Ring A ^2b are 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,5-difluoro-1, 4-Phenylene and 2,6-difluoro-1,4-phenylene. Preferred rings A ^1a , ring A ^2a , and ring A ^2b are 1,4-phenylene or 3-fluoro-1,4-phenylene to increase refractive index anisotropy.

Ring ^A3a is 1,4-cyclohexylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl. Is. The preferred ring ^A3a is 1,3-dioxane-2,5-diyl to increase the refractive index anisotropy. Rings A ^3b , A ^3c and A ^3d are 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,5-difluoro-1,4-phenylene, 2 , 6-Difluoro-1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl. .. Preferred rings A ^3b , ring A ^3c and ring A ^3d are 1,4-phenylene or 3-fluoro-1,4-phenylene to increase refractive index anisotropy.

Rings A and B are 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, or 2,5-difluoro-1. , 4-Phenylene. Preferred ring A or ring B is 1,4-cyclohexylene to reduce viscosity, or 1,4-phenylene to increase refractive index anisotropy.

または

であり、好ましくは

である。 Tetrahydropyran-2,5-diyl is

Or

And preferably

Is.

Z ^3a , Z ^3b , Z ^3c and Z ^3d are single bond, carbonyloxy or difluoromethyleneoxy. Preferred Z ^3a , Z ^3b , Z ^3c and Z ^3d are single bonds to reduce viscosity and to reduce dielectric loss tangent (tan δ).
Z ^4a is ethylene, vinylene, ethynylene, methyleneoxy, or carbonyloxy, and ^{any of Z 4a} may be a ^{single bond, but not all of Z 4a} are single bonds at the same time. Preferred Z ^4a is ethynylene to increase the refractive index anisotropy.

Divalent groups such as methyleneoxy are asymmetrical. In methyleneoxy, −CH ₂ O− is preferred over _{−OCH 2 −.} In carbonyloxy, -COO- is preferred over -OCO-. In difluoromethyleneoxy, −CF ₂ O− is preferred over _{−OCF 2 −.}

X ^3a , X ^3b , and X ^3c are hydrogen or fluorine, but X ^3a and X ^3b are not fluorine at the same time. Preferred X ^3a , X ^3b , and X ^3c are fluorine to increase the dielectric anisotropy.

Y ^3a is, -CN, -NCS, fluorine, chlorine, at least one hydrogen alkyl having carbon atoms 1 be replaced by halogen 12, at least one hydrogen from carbon atoms 1 be replaced by halogen Twelve alkoxys, or alkenyls having 2 to 12 carbon atoms, wherein at least one hydrogen may be replaced with a halogen. Preferred ^Y3a is fluorine to lower the lower limit temperature.

n ^1a is 1 or 2. The preferred n ^1a is 1 for lowering the viscosity and 2 for raising the upper limit temperature. n ^3a and n ^3b are 0 or 1. Preferred n ^3a and n ^3b are 0 to lower the lower limit temperature and 1 to increase the dielectric anisotropy. When n ^3a is 0 and n ^3b is 1, Z ^3c is difluoromethyleneoxy.

a is 1, 2, or 3. Preferred a is 1 for lowering the viscosity and 2 or 3 for raising the upper temperature limit.

Fifth, preferred component compounds are shown. Preferred compounds (1) are compounds (1-1) to compounds (1-9) according to Item 2. In these compounds, at least one of the first components is preferably compound (1-1), compound (1-4) or compound (1-5).

Preferred compounds (2) are compounds (2-1) to compounds (2-4) according to Item 4. In these compounds, at least one of the second components is preferably compound (2-1) or compound (2-2).

A preferable compound (3) is the compound (3-1) to the formula (3-41) according to Item 6. At least one of the third components is compound (3-6), compound (3-13), compound (3-14), compound (3-26), compound (3-27), compound (3-30), It is preferably compound (3-31), compound (3-32), compound (3-33), or compound (3-34).

Preferred compounds (4) are compounds (4-1) to compounds (4-20) according to Item 12. In these compounds, at least one of the fourth components is preferably compound (4-4), compound (4-9), compound (4-10), or compound (4-11).

Sixth, additives that may be added to the composition will be described. Such additives include optically active compounds, antioxidants, UV absorbers, light extinguishing agents, defoaming agents, polymerizable compounds, polymerization initiators, polymerization inhibitors, polar compounds and the like. An optically active compound is added to the composition for the purpose of inducing a helical structure of liquid crystal molecules to give a twist angle. Examples of such compounds are compound (6-1) to compound (6-5). The preferred proportion of the optically active compound is about 5% by mass or less. A more preferable ratio is in the range of about 0.01% by mass to about 2% by mass.

Compound (7-1) to prevent a decrease in resistivity due to heating in the atmosphere, or to maintain a large voltage retention not only at room temperature but also at temperatures close to the upper limit temperature after long-term use of the device. ) To an antioxidant such as compound (7-3) may be further added to the composition.

A compound having low volatility is effective in maintaining a large voltage holding ratio not only at room temperature but also at a temperature close to the upper limit temperature after the device has been used for a long time. The preferable ratio of the antioxidant is about 50 ppm or more in order to obtain the effect, and is about 600 ppm or less so as not to lower the upper limit temperature or raise the lower limit temperature. A more preferred ratio is in the range of about 100 ppm to about 300 ppm.

Preferred examples of UV absorbers are benzophenone derivatives, benzoate derivatives, triazole derivatives and the like. Light stabilizers such as sterically hindered amines are also preferred. Preferred examples of the light stabilizer are compounds (8-1) to compounds (8-16) and the like. The preferable ratio of these absorbents and stabilizers is about 50 ppm or more in order to obtain the effect, and is about 10,000 ppm or less so as not to lower the upper limit temperature or raise the lower limit temperature. A more preferred ratio is in the range of about 100 ppm to about 10000 ppm.

The quencher is a compound that prevents the decomposition of the liquid crystal compound by receiving the light energy absorbed by the liquid crystal compound and converting it into heat energy. Preferred examples of the quencher are compounds (9-1) to compounds (9-7) and the like. The preferred proportion of these quenchers is about 50 ppm or more to obtain the effect and about 20000 ppm or less to lower the lower limit temperature. A more preferred ratio is in the range of about 100 ppm to about 10000 ppm.

Polymerizable compounds are added to the composition to accommodate polymer-supported orientation (PSA) type devices. Preferred examples of the polymerizable compound are compounds such as acrylate, methacrylate, vinyl compound, vinyloxy compound, propenyl ether, epoxy compound (oxylane, oxetane), vinyl ketone and the like. A more preferred example is a derivative of acrylate or methacrylate. The preferable ratio of the polymerizable compound is about 0.05% by mass or more in order to obtain the effect, and about 10% by mass or less in order to prevent an increase in viscosity and poor orientation. A more preferable ratio is in the range of about 0.1% by mass to about 2% by mass. The polymerizable compound is polymerized by irradiation with ultraviolet rays. Polymerization may be carried out in the presence of an initiator such as a photopolymerization initiator. Appropriate conditions for polymerization, the appropriate type of initiator, and the appropriate amount are known to those of skill in the art and are described in the literature. For example, the photoinitiators Irgacure651®, Irgacure184® (registered trademark; BASF), or Darocur1173® are suitable for radical polymerization. The preferred proportion of photopolymerization initiator is in the range of about 0.1% by mass to about 5% by mass based on the mass of the polymerizable compound. A more preferable ratio is in the range of about 1% by mass to about 3% by mass.

When storing the polymerizable compound, a polymerization inhibitor may be added to prevent polymerization. The polymerizable compound is usually added to the composition without removing the polymerization inhibitor. Examples of polymerization inhibitors are hydroquinone, hydroquinone derivatives such as methylhydroquinone, 4-tert-butylcatechol, 4-methoxyphenol, phenothiazine and the like.

In this specification, the polar compound is an organic compound having polarity, and does not include a compound having an ionic bond. Atoms such as oxygen, sulfur, and nitrogen are more electrically negative and tend to have partial negative charges. Carbon and hydrogen tend to be neutral or have a partially positive charge. Polarity arises from the uneven distribution of partial charges between different atoms in a compound. For example, polar compounds have at least one of the partial structures such as -OH, -COOH, -SH, -NH _{2,>NH,> N-.}

Seventh, a method for synthesizing a component compound will be described. These compounds are Organic Synthesis, John Wiley & Sons, Inc., Organic Reactions, John Wiley & Sons, Inc, Comprehensive Syntheses Organic Syntheses It can be synthesized by the method described in books such as the New Experimental Chemistry Course (Maruzen). The composition is prepared from the compound thus obtained by a known method. For example, the component compounds are mixed and dissolved by heating.

Finally, the use of the composition will be described. The composition mainly has a lower limit temperature of about −10 ° C. or lower, an upper limit temperature of about 70 ° C. or higher, and a refractive index anisotropy in the range of about 0.20 to about 0.80. Compositions having a refractive index anisotropy in the range of about 0.25 to about 0.50 may be prepared by controlling the proportion of the constituent compounds or by mixing other liquid crystal compounds. By trial and error, a composition having a refractive index anisotropy in the range of about 0.33 to about 0.50 may be prepared. This composition can be used as a composition having a nematic phase, or can be used as an optically active composition by adding an optically active compound.

This composition can be used for an element used for phase control of an electromagnetic wave signal having a frequency of 1 GHz to 10 THz. Examples of applications include a millimeter-wave band variable phase shifter, a lidar (Light Detection and Ranger) element, and the like.

The present invention will be described in more detail by way of examples. The present invention is not limited by these examples. The present invention also includes a mixture of at least two of the compositions of the Examples.

Measurement method: The characteristics were measured by the following method. Many of these are methods described in the JEITA standard (JEITA ED-2521B) deliberated and enacted by the Japan Electronics and Information Technology Industries Association (JEITA), or modifications thereof. Met. A thin film transistor (TFT) was not attached to the TN element used for the measurement.

Upper limit temperature of the nematic phase (NI; ° C.): The sample was placed on a hot plate of a melting point measuring device equipped with a polarizing microscope and heated at a rate of 1 ° C./min. The temperature when a part of the sample changed from the nematic phase to the isotropic liquid was measured. The upper limit temperature of the nematic phase may be abbreviated as "upper limit temperature".

Minimum Temperature of a Nematic Phase _{(T C;} ℃): A sample having a nematic phase was put in a glass bottle, 0 ℃, -10 ℃, -20 ℃, then kept for 10 days in a freezer at -30 ° C., and -40 ℃ , The liquid crystal phase was observed. _{For example, TC} was described as <-20 ° C. when the sample remained in the nematic phase at −20 ° C. and changed to a crystalline or smectic phase at −30 ° C. The lower limit temperature of the nematic phase may be abbreviated as "lower limit temperature".

Viscosity (bulk viscosity; η; measured at 20 ° C.; mPa · s): An E-type rotational viscometer manufactured by Tokyo Keiki Co., Ltd. was used for the measurement.

Refractive index anisotropy (Δn; measured at 25 ° C.): The measurement was performed using light having a wavelength of 589 nm and using an Abbe refractometer with a polarizing plate attached to the eyepiece. After rubbing the surface of the main prism in one direction, the sample was dropped onto the main prism. The refractive index n‖ was measured when the direction of polarization was parallel to the direction of rubbing. The refractive index n⊥ was measured when the direction of polarization was perpendicular to the direction of rubbing. The value of optical anisotropy was calculated from the equation Δn = n ‖ −n ⊥.

Dielectric constant anisotropy (Δε; measured at 25 ° C.): The sample was placed in a TN device having a distance (cell gap) between two glass substrates of 9 μm and a twist angle of 80 degrees. A sine wave (10 V, 1 kHz) was applied to this device, and after 2 seconds, the permittivity (ε ‖) of the liquid crystal molecule in the long axis direction was measured. A sine wave (0.5 V, 1 kHz) was applied to this device, and after 2 seconds, the permittivity (ε⊥) of the liquid crystal molecule in the minor axis direction was measured. The value of permittivity anisotropy was calculated from the equation Δε ＝ ε‖−ε⊥.

Permittivity in the minor axis direction (ε⊥; measured at 25 ° C.): The sample was placed in a TN device having a distance (cell gap) between two glass substrates of 9 μm and a twist angle of 80 degrees. A sine wave (0.5 V, 1 kHz) was applied to this device, and after 2 seconds, the permittivity (ε⊥) of the liquid crystal molecule in the minor axis direction was measured.

Refractive index anisotropy at 50 GHz (measured at room temperature): Applied Optics, Vol. 44, No. 7, Measured by the method disclosed in p1150 (2005). The refractive index anisotropy was maintained in a static magnetic field of 0.3 T for 3 minutes by filling a variable short-circuit waveguide to which a window material was attached with a liquid crystal. A microwave of 50 GHz was input to the waveguide, and the amplitude ratio of the reflected wave to the incident wave was measured. The refractive index (ne, no) and loss parameters (αe, αo) were determined by measuring by changing the direction of the static magnetic field and the tube length of the short circuit. Refractive index anisotropy (Δn @ 50 GHz) was calculated from ne-no.

Tan δ and permittivity anisotropy at 50 GHz (measured at room temperature): To calculate the complex permittivity (ε', ε ”), the refractive index (n: ne, no) and loss parameters (α:) calculated in the previous section are used. .alpha.e, used the following relational expressions between .alpha.o). where c is the vacuum light velocity, omega is angular velocity, kappa is the extinction coefficient. dielectric anisotropy ([Delta] [epsilon] @ 50 GHz) is, n _e the Ipushiron'‖ from 'calculates a _{⊥, ε'‖-ε' ε} from _{n o} was calculated from _⊥. the tanδ (tanδ @ 50GHz) uses complex permittivity (ε ', ε "), tanδ It was calculated as = ε "/ ε'. Since anisotropy also appears in tan δ, the one with the larger value is described.
ε'= n ^2- κ ²
ε ”= 2nκ
α = 2ωκ / c

The compounds in the examples are represented by symbols based on the definitions in Table 2 below. In Table 2, the configuration for 1,4-cyclohexylene is trans. The number in parentheses after the symbol corresponds to the compound number. The symbol (-) means other liquid crystal compounds. The proportion (percentage) of the liquid crystal compound is a mass percentage (mass%) based on the mass of the liquid crystal composition. Finally, the characteristic values of the composition are summarized.

[Comparative Example 1] Liquid crystal composition 1
3-BB (F, F) XB (F, F) -F (3-6) 9%
3-BB (F) B (F, F) XB (F) -F (-) 3%
3-BB (F) B (F, F) XB (F, F) -F (-) 2%
4-BB (F) B (F, F) XB (F, F) -F (-) 7%
5-BB (F) B (F, F) XB (F, F) -F (-) 7%
3-BB (F, F) XB (F) B (F, F) -F (3-13) 6%
3-BB (F) B (F, F) -F (3-26) 3%
2-BTB-O1 (4-4) 8%
3-BTB-O1 (4-4) 8%
4-BTB-O1 (4-4) 8%
4-BTB-O2 (4-4) 8%
5-BTB-O1 (4-4) 7%
3-HB (F) TB-2 (4-9) 5%
3-HB (F) TB-3 (4-9) 5%
3-HB (F) TB-4 (4-9) 5%
3-H2BTB-2 (4-11) 3%
3-H2BTB-3 (4-11) 3%
3-H2BTB-4 (4-11) 3%
NI = 90.0 ° C; Tc <-20 ° C; Δn = 0.246; Δε = 9.4; η = 42.7 mPa · s; γ1 = 279 mPa · s
The refractive index anisotropy, dielectric anisotropy and dielectric loss tangent (tan δ) of the liquid crystal composition 1 at 50 GHz were as follows.
Δn @ 50GHz = 0.16
Δε @ 50GHz = 0.49
tan δ @ 50GHz = 0.013

[Comparative Example 2] Liquid crystal composition 2
1-BB (F) B-2V (1-4) 6%
2-BB (F) B-2V (1-4) 6%
3-BB (F) B-2V (1-4) 7%
3-BB (F, F) XB (F, F) -F (3-6) 5%
3-BB (F, F) XB (F) B (F, F) -F (3-13) 10%
3-BB (F) B (F, F) -F (3-26) 9%
2-BTB-O1 (4-4) 7%
3-BTB-O1 (4-4) 7%
4-BTB-O1 (4-4) 7%
4-BTB-O2 (4-4) 7%
5-BTB-O1 (4-4) 6%
3-HB (F) TB-2 (4-9) 7%
3-HB (F) TB-3 (4-9) 6%
3-HB (F) TB-4 (4-9) 6%
3-H2BTB-2 (4-11) 2%
3-H2BTB-3 (4-11) 2%
NI = 100.6 ° C; Tc <-30 ° C; Δn = 0.258; Δε = 5.1; η = 36.4 mPa · s

The refractive index anisotropy, dielectric anisotropy and dielectric loss tangent (tan δ) of the liquid crystal composition 2 at 50 GHz were as follows.
Δn @ 50GHz = 0.17
Δε @ 50GHz = 0.57
tan δ @ 50GHz = 0.010

[Comparative Example 3] Liquid crystal composition 3
3-BB (F, F) XB (F, F) -F (3-6) 12%
3-BB (F) B (F, F) -F (3-26) 15%
2-BTB-O1 (4-4) 8%
3-BTB-O1 (4-4) 8%
4-BTB-O1 (4-4) 8%
4-BTB-O2 (4-4) 8%
5-BTB-O1 (4-4) 7%
3-HB (F) TB-2 (4-9) 9%
3-HB (F) TB-3 (4-9) 8%
3-HB (F) TB-4 (4-9) 8%
3-H2BTB-2 (4-11) 4%
3-H2BTB-3 (4-11) 3%
3-H2BTB-4 (4-11) 2%
NI = 90.1 ° C; Tc <-30 ° C; Δn = 0.247; Δε = 5.0; η = 32.4 mPa · s

The refractive index anisotropy, dielectric anisotropy and dielectric loss tangent (tan δ) of the liquid crystal composition 3 at 50 GHz were as follows.
Δn @ 50GHz = 0.17
Δε @ 50GHz = 0.57
tan δ @ 50GHz = 0.011

[Comparative Example 4] Liquid crystal composition 4
3-BB (F, F) XB (F, F) -F (3-6) 1%
3-BB (F, F) XB (F) B (F, F) -F (3-13) 12%
3-BB (F) B (F, F) -F (3-26) 14%
2-BTB-O1 (4-4) 8%
3-BTB-O1 (4-4) 8%
4-BTB-O1 (4-4) 8%
4-BTB-O2 (4-4) 8%
5-BTB-O1 (4-4) 7%
3-HB (F) TB-2 (4-9) 9%
3-HB (F) TB-3 (4-9) 8%
3-HB (F) TB-4 (4-9) 8%
3-H2BTB-2 (4-11) 4%
3-H2BTB-3 (4-11) 3%
3-H2BTB-4 (4-11) 2%
NI = 99.3 ° C; Tc <-30 ° C; Δn = 0.255; Δε = 5.5; η = 36.4 mPa · s

The refractive index anisotropy, dielectric anisotropy and dielectric loss tangent (tan δ) of the liquid crystal composition 4 at 50 GHz were as follows.
Δn @ 50GHz = 0.18
Δε @ 50GHz = 0.61
tan δ @ 50GHz = 0.013

[Comparative Example 5] Liquid crystal composition 5
3-BB (F, F) XB (F, F) -F (3-6) 1%
3-BB (F, F) XB (F) B (F, F) -F (3-13) 12%
3-GB (F) B (F) B (F) -F (3-30) 8%
3-GBB (F) B (F, F) -F (3-31) 6%
4-GBB (F) B (F, F) -F (3-31) 6%
2-BTB-O1 (4-4) 8%
3-BTB-O1 (4-4) 8%
4-BTB-O1 (4-4) 8%
4-BTB-O2 (4-4) 8%
5-BTB-O1 (4-4) 7%
3-HB (F) TB-2 (4-9) 7%
3-HB (F) TB-3 (4-9) 6%
3-HB (F) TB-4 (4-9) 6%
3-H2BTB-2 (4-11) 4%
3-H2BTB-3 (4-11) 3%
3-H2BTB-4 (4-11) 2%
NI = 118.8 ° C; Tc <-30 ° C; Δn = 0.259; Δε = 8.2; η = 54.7 mPa · s

The refractive index anisotropy, dielectric anisotropy and dielectric loss tangent (tan δ) of the liquid crystal composition 5 at 50 GHz were as follows.
Δn @ 50GHz = 0.13
Δε @ 50GHz = 0.44
tan δ @ 50GHz = 0.010

[Example 1] Liquid crystal composition 6
1-BB-3 (1-1) 9%
3-HB-O2 (-) 8%
1-BB (F) B-2V (1-4) 4%
2-BB (F) B-2V (1-4) 4%
3-BB (F) B-2V (1-4) 5%
2-BB (F) B-3 (1-4) 10%
2-BB (F) B-5 (1-4) 10%
3-BB (F) B-5 (1-4) 10%
3-BB (2F, 5F) B-3 (1-5) 5%
5-HBB (F) B-2 (2-2) 6%
5-HBB (F) B-3 (2-2) 7%
3-BB (F, F) XB (F, F) -F (3-6) 10%
3-BB (F, F) XB (F) B (F, F) -F (3-13) 12%
NI = 108.9 ° C; Tc <-20 ° C; Δn = 0.225; Δε = 5.2; η = 45.8 mPa · s

The refractive index anisotropy, dielectric anisotropy and dielectric loss tangent (tan δ) of the liquid crystal composition 6 at 50 GHz were as follows.
Δn @ 50GHz = 0.16
Δε @ 50GHz = 0.53
tan δ @ 50GHz = 0.006

[Example 2] Liquid crystal composition 7
1-BB-3 (1-1) 9%
3-HB-O2 (-) 8%
1-BB (F) B-2V (1-4) 6%
2-BB (F) B-2V (1-4) 6%
3-BB (F) B-2V (1-4) 5%
2-BB (F) B-5 (1-4) 10%
3-BB (F) B-5 (1-4) 10%
3-BB (2F, 5F) B-3 (1-5) 5%
5-HBB (F) B-2 (2-2) 6%
5-HBB (F) B-3 (2-2) 7%
3-BB (F, F) XB (F, F) -F (3-6) 1%
3-BB (F, F) XB (F) B (F, F) -F (3-13) 17%
3-BB (F) BC (3-33) 10%
NI = 126.1 ° C; Tc <-20 ° C; Δn = 0.240; Δε = 8.1

The refractive index anisotropy, dielectric anisotropy and dielectric loss tangent (tan δ) of the liquid crystal composition 7 at 50 GHz were as follows.
Δn @ 50GHz = 0.16
Δε @ 50GHz = 0.53
tan δ @ 50GHz = 0.009

[Example 3] Liquid crystal composition 8
1-BB-3 (1-1) 9%
3-HB-O2 (-) 8%
1-BB (F) B-2V (1-4) 6%
2-BB (F) B-2V (1-4) 6%
3-BB (F) B-2V (1-4) 7%
2-BB (F) B-3 (1-4) 8%
2-BB (F) B-5 (1-4) 8%
3-BB (F) B-5 (1-4) 8%
3-BB (2F, 5F) B-3 (1-5) 5%
5-HBB (F) B-2 (2-2) 6%
5-HBB (F) B-3 (2-2) 7%
3-BB (F, F) XB (F, F) -F (3-6) 1%
3-BB (F, F) XB (F) B (F, F) -F (3-13) 12%
3-GB (F) B (F) B (F) -F (3-30) 8%
3-GBB (F) B (F, F) -F (3-31) 1%
NI = 128.4 ° C; Tc <-20 ° C; Δn = 0.236; Δε = 5.3; η = 51.7 mPa · s

The refractive index anisotropy, dielectric anisotropy and dielectric loss tangent (tan δ) of the liquid crystal composition 8 at 50 GHz were as follows.
Δn @ 50GHz = 0.17
Δε @ 50GHz = 0.57
tan δ @ 50GHz = 0.009

[Example 4] Liquid crystal composition 9
1-BB-3 (1-1) 8%
1-BB-5 (1-1) 7%
3-HB-O2 (-) 10%
1-BB (F) B-2V (1-4) 4%
2-BB (F) B-2V (1-4) 4%
3-BB (F) B-2V (1-4) 5%
2-BB (F) B-3 (1-4) 4%
2-BB (F) B-5 (1-4) 4%
3-BB (F) B-5 (1-4) 4%
3-BB (2F, 5F) B-3 (1-5) 4%
5-HBB (F) B-2 (2-2) 14%
5-HBB (F) B-3 (2-2) 14%
3-BB (F, F) XB (F, F) -F (3-6) 1%
3-BB (F, F) XB (F) B (F, F) -F (3-13) 17%
NI = 129.5 ° C; Tc <-20 ° C; Δn = 0.222; Δε = 4.3; η = 47.2 mPa · s

The refractive index anisotropy, dielectric anisotropy and dielectric loss tangent (tan δ) of the liquid crystal composition 9 at 50 GHz were as follows.
Δn @ 50GHz = 0.14
Δε @ 50GHz = 0.46
tan δ @ 50GHz = 0.009

[Example 5] Liquid crystal composition 10
1-BB (F) B-2V (1-4) 4%
2-BB (F) B-2V (1-4) 4%
3-BB (F) B-2V (1-4) 5%
2-BB (F) B-3 (1-4) 8%
2-BB (F) B-5 (1-4) 7%
3-BB (F) B-5 (1-4) 7%
5-HBB (F) B-2 (2-2) 6%
5-HBB (F) B-3 (2-2) 7%
3-BB (F, F) XB (F, F) -F (3-6) 10%
3-BB (F, F) XB (F) B (F, F) -F (3-13) 12%
2-BTB-O1 (4-4) 6%
3-BTB-O1 (4-4) 6%
4-BTB-O1 (4-4) 6%
4-BTB-O2 (4-4) 6%
5-BTB-O1 (4-4) 6%
NI = 110.0 ° C; Tc <-20 ° C; Δn = 0.256; Δε = 5.2; η = 47.6 mPa · s

The refractive index anisotropy and the dielectric constant anisotropy of the liquid crystal composition 10 at 50 GHz were as follows.
Δn @ 50GHz = 0.17
Δε @ 50GHz = 0.59

[Example 6] Liquid crystal composition 11
3-HB-O2 (-) 15%
1-BB (F) B-2V (1-4) 8%
2-BB (F) B-2V (1-4) 8%
3-BB (F) B-2V (1-4) 7%
2-BB (F) B-5 (1-4) 4%
3-BB (F) B-5 (1-4) 4%
3-BB (2F, 5F) B-3 (1-5) 5%
5-HBB (F) B-2 (2-2) 3%
5-HBB (F) B-3 (2-2) 3%
3-BB (F, F) XB (F, F) -F (3-6) 1%
3-BB (F, F) XB (F) B (F, F) -F (3-13) 22%
3-BB (F) BC (3-33) 10%
2-BTB-O1 (4-4) 2%
3-BTB-O1 (4-4) 2%
4-BTB-O1 (4-4) 2%
4-BTB-O2 (4-4) 2%
5-BTB-O1 (4-4) 2%
NI = 112.0 ° C; Tc <-20 ° C; Δn = 0.237; Δε = 9.8

The refractive index anisotropy and the dielectric constant anisotropy of the liquid crystal composition 11 at 50 GHz were as follows.
Δn @ 50GHz = 0.16
Δε @ 50GHz = 0.54

[Example 7] Liquid crystal composition 12
2-BTB-O1 (4-4) 8%
3-BTB-O1 (4-4) 7%
4-BTB-O1 (4-4) 7%
4-BTB-O2 (4-4) 7%
5-BTB-O1 (4-4) 7%
1-BB (F) B-2V (1-4) 6%
2-BB (F) B-2V (1-4) 6%
3-BB (F) B-2V (1-4) 6%
2-BB (F) B-3 (1-4) 8%
2-BB (F) B-5 (1-4) 8%
3-BB (F) B-5 (1-4) 8%
3-BB (2F, 5F) B-3 (1-5) 5%
3-GB (F) B (F) B (F) -F (3-30) 6%
3-GBB (F) B (F, F) -F (3-31) 4%
4-GBB (F) B (F, F) -F (3-31) 4%
5-HBB (F) B-3 (2-2) 3%
NI = 115.5 ° C; Tc <-20 ° C; Δn = 0.275; Δε = 2.9

The refractive index anisotropy, dielectric anisotropy and dielectric loss tangent (tan δ) of the liquid crystal composition 12 at 50 GHz were as follows.
Δn @ 50GHz = 0.19
Δε @ 50GHz = 0.65
tan δ @ 50GHz = 0.011

[Example 8] Liquid crystal composition 13
2-BTB-O1 (4-4) 8%
3-BTB-O1 (4-4) 7%
4-BTB-O1 (4-4) 7%
4-BTB-O2 (4-4) 7%
5-BTB-O1 (4-4) 7%
2-BB (F) B-3 (1-4) 12%
2-BB (F) B-5 (1-4) 11%
3-BB (F) TB-4 (4-10) 24%
3-GB (F) B (F) B (F) -F (3-30) 6%
3-GBB (F) B (F, F) -F (3-31) 4%
4-GBB (F) B (F, F) -F (3-31) 4%
5-HBB (F) B-3 (2-2) 3%
NI = 126.6 ° C; Tc <-30 ° C; Δn = 0.300; Δε = 2.8

The refractive index anisotropy, dielectric anisotropy and dielectric loss tangent (tan δ) of the liquid crystal composition 13 at 50 GHz were as follows.
Δn @ 50GHz = 0.20
Δε @ 50GHz = 0.67
tan δ @ 50GHz = 0.010

[Example 9] Liquid crystal composition 14
2-BTB-O1 (4-4) 7%
3-BTB-O1 (4-4) 7%
4-BTB-O1 (4-4) 7%
4-BTB-O2 (4-4) 7%
5-BTB-O1 (4-4) 6%
1-BB (F) B-2V (1-4) 7%
2-BB (F) B-2V (1-4) 7%
3-BB (F) B-2V (1-4) 6%
3-BB (F) TB-4 (4-10) 24%
3-BB (F, F) XB (F, F) -F (3-6) 1%
3-BB (F, F) XB (F) B (F, F) -F (3-13) 13%
3-GB (F) B (F) B (F) -F (3-30) 4%
4-GBB (F) B (F, F) -F (3-31) 1%
5-HBB (F) B-3 (2-2) 3%
NI = 121.1 ° C; Tc <-30 ° C; Δn = 0.290; Δε = 4.8

The refractive index anisotropy, dielectric anisotropy and dielectric loss tangent (tan δ) of the liquid crystal composition 14 at 50 GHz were as follows.
Δn @ 50GHz = 0.22
Δε @ 50GHz = 0.75
tan δ @ 50GHz = 0.011

The Δn @ 50 GHz of the compositions of Comparative Examples 1 to 5 was 0.13 to 0.17, and Δε @ 50 GHz was 0.44 to 0.57. The dielectric loss tangent (tan δ) at 50 GHz ranged from 0.010 to 0.013.

On the other hand, the Δn @ 50 GHz of Examples 1 to 9 was 0.14 to 0.22, and the Δ dielectric constant (@ 50 GHz) was 0.46 to 0.75. The tan δ @ 50 GHz of the composition was 0.006 to 0.011. Therefore, it is concluded that the liquid crystal composition of the present invention has high Δn @ 50 GHz, high Δε @ 50 GHz and low tan δ @ 50 GHz and has better properties.

Further, the compositions of Comparative Examples 1 to 5 contain a compound having ethylene as a linker as shown in the formula (4-11). As a constituent compound of the composition, the more the linker contains a compound having a binding group, the higher the dielectric loss tangent (tan δ) becomes.

The liquid crystal composition having a lower dielectric loss tangent (tan δ) is preferably composed only of a compound having no bonding group in the linker, that is, a compound formed only by a single bond.

When it is important to make the dielectric loss tangent (tan δ) in the frequency domain used for phase control smaller as the liquid crystal composition of the element used for the phase control of the electromagnetic signal, the compositions of Comparative Examples 1 to 5 are used. It is desirable that the composition does not contain a compound having a binding group to the linker such as the formula (3-6), the formula (3-13), the formula (4-9), and the formula (4-11) contained in the product. It is also preferred to include such compounds in the composition in consideration of the balance between the high upper limit temperature of the phase, the lower lower limit temperature of the nematic phase, the low viscosity, the stability against heat and the like. In the liquid crystal composition of the present invention, even if such a compound is included, a small dielectric loss tangent (tan δ) can be realized.

The liquid crystal composition of the present invention has a high upper limit temperature of the nematic phase, a lower lower limit temperature of the nematic phase, a low viscosity, a large refractive index anisotropy in the frequency domain used for phase control, a large dielectric constant anisotropy, and a small value. In properties such as dielectric anisotropy (tan δ), it satisfies at least one property or has an appropriate balance with respect to at least two properties. The device containing this composition can be used for phase control of an electromagnetic wave signal having a frequency of 1 GHz to 10 THz.

Claims (16)

At least one compound selected from the group of compounds represented by the formula (1) as the first component, and at least one compound selected from the group of compounds represented by the formula (2) as the second component. A liquid crystal composition used for phase control of an electromagnetic wave signal having a frequency of 1 GHz to 10 THz, which contains at least one compound selected from the group of compounds represented by the formula (3) as a third component. ..

In formulas (1), (2), and (3), R ^1a , R ^1b , R ^2a , and R ^2b are alkyl having 1 to 20 carbon atoms, alkoxy having 1 to 20 carbon atoms, and 2 carbon atoms. To 20 alkenyl, or 2 to 20 carbon alkenyloxy; R ^3a is an alkyl 1 to 20 carbon or an alkenyl 2 to 20 carbon; ring A ^1a , ring A ^2a , and ring A. ^2b is 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,5-difluoro-1,4-phenylene, 2,6-difluoro-1. , 4-Phenylene; ring ^A3a is 1,4-cyclohexylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydro. It is pyran-2,5-diyl; ring A ^3b , ring A ^3c and ring A ^3d are 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,5. -Difluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyridine-2,5-diyl, pyrimidine-2,5-diyl, 1,3-dioxane-2,5-diyl, or Tetrahydropyrene-2,5-diyl; Z ^3a , Z ^3b , Z ^3c and Z ^3d are single-bonded, carbonyloxy or difluoromethyleneoxy;
X ^3a , X ^3b , and X ^3c are hydrogen or fluorine, but X ^3a and X ^3b are not fluorine at the same time; Y ^3a is -CN, -NCS, fluorine, chlorine, at least one hydrogen. Is an alkyl having 1 to 12 carbon atoms which may be replaced by a halogen, an alkoxy having 1 to 12 carbon atoms which may be replaced by a halogen at least one hydrogen, or a carbon which may be replaced by a halogen at least one hydrogen. The numbers 2 to 12 are alkenyl; n ^1a is 1 or 2; n ^3a and n ^3b are 0 or 1, n ^3a is 0, n ^3b is 1, Z ^3c is difluoromethyleneoxy. Is. The liquid crystal composition according to claim 1, which contains at least one compound selected from the compounds represented by the formulas (1-1) to (1-9) as the first component.

In these formulas, R ^1a and R ^1b are alkyls having 1 to 20 carbon atoms, alkoxy having 1 to 20 carbon atoms, alkenyl having 2 to 20 carbon atoms, or alkenyloxy having 2 to 20 carbon atoms. The liquid crystal composition according to claim 1 or 2, wherein the ratio of the first component is in the range of 3% by mass to 80% by mass based on the mass of the liquid crystal composition. The liquid crystal composition according to any one of claims 1 to 3, which contains at least one compound selected from the compounds represented by the formulas (2-1) to (2-4) as the second component. Stuff.

In these formulas, R ^2a and R ^2b are alkyls having 1 to 20 carbon atoms, alkoxys having 1 to 20 carbon atoms, alkenyl having 2 to 20 carbon atoms, or alkenyloxy having 2 to 20 carbon atoms. The liquid crystal composition according to any one of claims 1 to 4, wherein the proportion of the second component is in the range of 3% by mass to 40% by mass based on the mass of the liquid crystal composition. The liquid crystal composition according to any one of claims 1 to 5, which contains at least one compound selected from the compounds represented by the formulas (3-1) to (3-41) as the third component. Stuff.

In these formulas, R ^3a is an alkyl having 1 to 20 carbon atoms or an alkenyl having 2 to 20 carbon atoms. Any one of claims 1 to 5 ^{, wherein Z 3a} , Z ^3b , Z ^3c and Z ^3d are all single bonds in all the compounds represented by the formula (3) according to claim 1 as the third component. The liquid crystal composition according to the item. The liquid crystal composition according to any one of claims 1 to 7, wherein the ratio of the third component is in the range of 3% by mass to 50% by mass based on the mass of the liquid crystal composition. The liquid crystal composition according to any one of claims 1 to 8, further containing at least one compound selected from the compounds represented by the formula (4) as the fourth component.

In formula (4), R ^4a and R ^4b have an alkyl having 1 to 12 carbon atoms, an alkoxy having 1 to 12 carbon atoms, an alkenyl having 2 to 12 carbon atoms, or at least one hydrogen being replaced with fluorine or chlorine. It is an alkoxy having 2 to 12 carbon atoms; rings A and B are 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-. Phenylene, 2,5-difluoro-1,4-phenylene or 2,6-difluoro-1,4-phenylene; Z ^4a is ethylene, vinylene, ethynylene, methyleneoxy, or carbonyloxy; a is 1, 2, or 3; when a is 2 or 3, the plurality of rings A and Z ^4a may be the same or different, and ^{any of Z 4a} may be a single bond. , Z ^4a are not all single bonds at the same time. The liquid crystal composition according to claim 9, which contains at least one compound selected from the compounds represented by the formulas (4-1) to (4-20) as the fourth component.

R ^4a and R ^4b are alkyls with 1 to 12 carbon atoms, alkoxys with 1 to 12 carbon atoms, alkenyl with 2 to 12 carbon atoms, or 2 to 12 carbon atoms in which at least one hydrogen is replaced with fluorine or chlorine. It is alkenyl. The liquid crystal composition according to claim 9 or 10, wherein the proportion of the fourth component is in the range of 3% by mass to 80% by mass based on the mass of the liquid crystal composition. The liquid crystal composition according to any one of claims 1 to 11, wherein the refractive index anisotropy at 25 ° C. at a wavelength of 589 nm is 0.25 to 0.80. The liquid crystal composition according to any one of claims 1 to 11, wherein the dielectric anisotropy at 25 ° C. at any frequency from 1 GHz to 10 THz is in the range of 0.40 to 2.0. The liquid crystal composition according to any one of claims 1 to 13, which comprises an optically active compound. The liquid crystal composition according to any one of claims 1 to 13, which comprises a polymerizable compound. An element used for phase control of an electromagnetic wave signal having a frequency of any one of 1 GHz to 10 THz, which contains the liquid crystal composition according to any one of claims 1 to 15.