JP2006225588A - Liquid crystal composition, display element and compound containing trifluoronaphthalene derivative - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid crystal composition, a display element and a compound with a negative permittivity anisotropy and a large absolute value. <P>SOLUTION: The nematic liquid crystal composition with negative permittivity anisotropy containing one or more trifluoronaphthalene derivatives shown by general formula (I) and one or more compounds shown by general formula (II), and the display element using the nematic liquid crystal composition. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a liquid crystal composition containing a trifluoronaphthalene derivative having a negative dielectric anisotropy and a large absolute value, a liquid crystal display device using the same, and a liquid crystal compound, which are useful as an electro-optical liquid crystal display material.

  Liquid crystal display elements are currently widely used because of their excellent features such as low voltage operation and thin display. Conventional liquid crystal display element display methods include TN (twisted nematic), STN (super twisted nematic), or active matrix (TFT: thin film transistor) based on TN, and these have positive dielectric anisotropy values. The liquid crystal composition is used. However, one of the disadvantages of these display methods is a narrow viewing angle, and with the increasing demand for larger liquid crystal panels in recent years, the improvement has become a major issue.

  In recent years, display methods such as vertical alignment and IPS (in-plane switching) have been newly put to practical use as a solution. The vertical alignment method is a method in which the viewing angle is improved by utilizing the vertical alignment of liquid crystal molecules, and a liquid crystal composition having a negative dielectric anisotropy value is used. IPS is a method that improves the viewing angle by switching liquid crystal molecules using a horizontal electric field in the horizontal direction with respect to the glass substrate, and uses liquid crystal compositions with positive or negative dielectric anisotropy. Is done. As described above, the vertical alignment method and the IPS, which are effective display methods for improving the viewing angle, require a liquid crystal compound and a liquid crystal composition having a negative dielectric anisotropy value. It has become. Conventionally, compounds having a 2,3-difluorophenylene group have been mainly used for liquid crystal compositions having negative dielectric anisotropy (Patent Document 1). However, a liquid crystal composition using this compound has a problem that the absolute value of dielectric anisotropy is not sufficiently large (Patent Document 2).

  There is a trifluoronaphthalene derivative as a compound having a large absolute value and negative dielectric anisotropy, and general disclosure including many compounds has already been made (Patent Document 3). However, the production of the trifluoronaphthalene skeleton is not always easy, and it is not recognized that the compound is disclosed in the entire range disclosed in the cited document. Further, the cited document is intended for use in ferroelectric liquid crystal compositions, and which compounds in a wide disclosure range are specifically used as nematic liquid crystal compositions having a negative dielectric anisotropy. There is no disclosure regarding the effect of using such compounds in combination.

  On the other hand, a liquid crystal composition using a trifluoronaphthalene-based compound is already known, but there is no disclosure of a liquid crystal composition using a compound having a cyclohexylmethoxy group at the 6-position of a naphthalene ring (Patent Document 4, 5 and 6).

In addition, based on the knowledge that a compound having an alkoxy group at the 2-position of the benzene ring and a cyclohexylmethoxy group at the 6-position is chemically unstable and cannot be used, it has an alkoxy group at the 2-position of the naphthalene ring and In addition, since a compound having a cyclohexylmethoxy group was also considered to be chemically unstable and cannot be used as a liquid crystal material, development of the compound as a liquid crystal material has not progressed. (Non-Patent Document 1)
JP-T-2-503441 (Example of 8 pages) JP-A-10-176167 (Example of page 10) German Patent Application Publication No. 19522195 (page 12 production method) JP 2001-40354 A JP 2002-376844 A JP 2002-376845 A Numata, “Trends in Liquid Crystal Materials,” Monthly Display, March 1998, Volume 4, Issue 3 (5 pages)

  It is to provide a liquid crystal composition and a display element having a negative dielectric anisotropy and a large absolute value, and to provide a compound having a negative dielectric anisotropy and a large absolute value. .

  As a result of studying a trifluoronaphthalene derivative, a nematic liquid crystal composition using the trifluoronaphthalene derivative, and a display element, the present inventor has completed the present invention.

  The present invention relates to general formula (I)

(In the formula, R ^a represents ^a linear alkyl group having 1 to 7 carbon atoms or a linear alkenyl group having 2 to 7 carbon atoms, and R ^b represents a linear alkyl group having 1 to 7 carbon atoms. Represents a straight-chain alkoxyl group having 1 to 7 carbon atoms, a straight-chain alkenyl group having 2 to 7 carbon atoms or a straight-chain alkenyloxy group having 2 to 7 carbon atoms, and M ^a and M ^p are respectively Independently represents a single bond, —CH ₂ CH ₂ —, —CH═CH—, —OCH ₂ —, —CH ₂ O—, —OCF ₂ —, —CF ₂ O—, —OCO— or —COO—. , G ^a and G ^b each independently represent a trans-1,4-cyclohexylene group or a 1,4-phenylene group, and p1 and p2 each independently represent 0 or 1. Contains one or more trifluoronaphthalene derivatives and has the general formula (II)

(In the formula, R ^c represents a linear alkyl group or alkenyl group having 1 to 7 carbon atoms, and R ^d represents a linear alkyl group, alkenyl group, alkoxyl group or alkenyloxy group having 1 to 12 carbon atoms. P3 represents 0 or 1, M ^b and M ^c each independently represents a single bond, —COO—, —CH═CH— or —CH ₂ CH ₂ —, G ^c represents trans-1, A liquid crystal composition containing one or more compounds represented by 4-cyclohexylene group or -1,4-phenylene group) and a liquid crystal display device using the same are provided.

Also,
Formula (I-1)

(In the formula, R ^a represents ^a linear alkyl group having 1 to 7 carbon atoms or a linear alkenyl group having 2 to 7 carbon atoms, and R ^b represents a linear alkyl group having 1 to 7 carbon atoms. Represents a straight-chain alkoxyl group having 1 to 7 carbon atoms, a straight-chain alkenyl group having 2 to 7 carbon atoms or a straight-chain alkenyloxy group having 2 to 7 carbon atoms, and M ^a and M ^p are respectively Independently represents a single bond, —CH ₂ CH ₂ —, —CH═CH—, —OCH ₂ —, —CH ₂ O—, —OCF ₂ — or —CF ₂ O—, wherein G ^a and G ^b are each Independently represents a trans-1,4-cyclohexylene group or a 1,4-phenylene group, and p1 and p2 each independently represents 0 or 1.) To do.

  The liquid crystal composition of the present invention is characterized by having a negative dielectric anisotropy and a large absolute value, and a display device using this is useful as a liquid crystal display device such as a vertical alignment type or IPS. Further, the trifluoronaphthalene derivative of the present invention has a negative dielectric anisotropy and a large absolute value, and is useful as a constituent member of a liquid crystal composition for a vertical alignment method, IPS, and the like.

In the general formula (I), R ^a is preferably a linear alkyl group having 1 to 7 carbon atoms, more preferably an ethyl group, a propyl group, a butyl group or a pentyl group. R ^b is preferably a linear alkyl group having 1 to 7 carbon atoms or an alkoxyl group, more preferably an ethyl group, a propyl group, a butyl group, a pentyl group, a methoxy group, an ethoxy group, a propoxy group, a butoxy group or a pentyloxy group. preferable. p1 is preferably 0 or 1, and more preferably p2 represents 0. Ma is preferably ^a single bond, —CH ₂ CH ₂ —, —OCH ₂ — or —OCF ₂ —, more preferably —CH ₂ CH ₂ — or —OCH ₂ —. M ^p is preferably a single bond or —CH ₂ CH ₂ —, and more preferably a single bond. G ^a and G ^b are preferably a trans-1,4-cyclohexylene group, and specifically, a compound represented by the following general formula is particularly preferable.

In the general formula (II), R ^c is preferably a linear alkyl group having 2 to 7 carbon atoms, a 1-alkenyl group having 2 to 5 carbon atoms or a 3-alkenyl group having 4 to 5 carbon atoms. The chain alkyl group is more preferably an ethyl group, propyl group, butyl group or pentyl group, the 1-alkenyl group is more preferably a vinyl group or a trans-1-propenyl group, and the 3-alkenyl group is a 3-butenyl group. Or a trans-3-pentenyl group is more preferable. R ^d is a linear alkyl group having 1 to 7 carbon atoms, a 1-alkenyl group having 2 to 5 carbon atoms, a 3-alkenyl group having 4 to 5 carbon atoms, or a linear chain having 1 to 3 carbon atoms. Alkoxyl groups are preferred. If the M ^b is present, at least one of M ^b and M ^c is a single bond.

  As the compound represented by the general formula (II), compounds represented by the following general formula (II-1) to general formula (II-14) are preferable, and the general formula (II-1), the general formula (II- The compound represented by 2), general formula (II-3), general formula (II-5) or general formula (II-6) is particularly preferred.

In the above formula, R ¹ and R ² are each independently a linear alkyl group having 1 to 7 carbon atoms, a 1-alkenyl group having 2 to 3 carbon atoms, or a 3-alkenyl group having 4 to 5 carbon atoms. R ³ represents a linear alkyl group having 1 to 5 carbon atoms or a linear 2-alkenyl group having 3 to ⁴ carbon atoms, and R ⁴ represents a linear alkyl group having 1 to 3 carbon atoms. R ⁵ represents a linear alkyl group having 1 to 3 carbon atoms or a linear 2-alkenyl group having 3 to 4 carbon atoms.

  In the liquid crystal composition of the present invention, the compound represented by the general formula (I) is preferably contained in the composition in an amount of 1% by mass (hereinafter,% in the composition represents mass%) and 50% or less. It is more preferable that the content is from 40% to 40%, and it is more preferable that the content is from 4 to 30%. The compound represented by the general formula (II) is preferably contained in an amount of 1% to 50%, more preferably 2% to 40%.

  In the liquid crystal composition of the present invention, the general formula (III)

(式中、R^eは炭素原子数1〜7のアルキル基を表し、R^fは炭素原子数1〜7の直鎖状アルキル基、アルコキシル基またはアルケニルオキシ基を表し、p4は0または1を表し、M^dおよびM^eはそれぞれ独立的に単結合、-CH₂CH₂-、-CH=CH-、-OCH₂-、-CH₂O-、-OCF₂-、-CF₂O-または-COO-を表し、G^dはトランス-1,4-シクロヘキシレン基あるいは1〜2個のフッ素により置換されていてもよい-1,4-フェニレン基を表す。)で表される2,3-ジフルオロ-1,4-フェニレン誘導体の1種または2種以上を含有していても良い。

(Wherein R ^e represents an alkyl group having 1 to 7 carbon atoms, R ^f represents a linear alkyl group having 1 to 7 carbon atoms, an alkoxyl group or an alkenyloxy group, and p4 represents 0 or 1) M ^d and ^Me are each independently a single bond, —CH ₂ CH ₂ —, —CH═CH—, —OCH ₂ —, —CH ₂ O—, —OCF ₂ —, —CF ₂ O— or represents -COO-, 2,3 G ^d is represented by represents trans-1,4-cyclohexylene group or one to two optionally substituted 1,4-phenylene group by fluorine.) One or more of -difluoro-1,4-phenylene derivatives may be contained.

In the general formula (III), R ^e is preferably a linear alkyl group having 2 to 7 carbon atoms. R ^f is preferably a linear alkyl group having 1 to 5 carbon atoms or a linear alkoxyl group, and a linear alkyl group having 1 to 4 carbon atoms or a linear alkoxyl group having 1 to 4 carbon atoms. Particularly preferred. Preferably one of the M ^d and M ^e is a single bond and the other is a single bond, -CH ₂ CH ₂ - is preferred or -COO- in which.

  The general formula (III) includes a large number of compounds, but compounds represented by the following general formulas (III-1) to (III-7) are preferable.

In the above formula, R ⁶ represents a linear alkyl group having 1 to ⁷ carbon atoms, and R ⁷ is a linear alkyl group having 1 to 5 carbon atoms or a linear alkoxyl group having 1 to 4 carbon atoms. Represents.
Further, in the liquid crystal composition of the present invention, the general formula (IV) ~ general formula (VIII)

(Wherein R ^g , R ⁱ , R ^k and R ^m represent a linear alkyl group having 1 to 7 carbon atoms, and R ^h , R ^j and R ⁿ are linear chains having 1 to 7 carbon atoms. Represents a linear alkyl group, an alkoxyl group or an alkenyloxy group, R ¹ represents a linear alkyl group having 1 to 7 carbon atoms, and R ^o represents a linear alkyl group having 1 to 7 carbon atoms, an alkoxyl group or A linear alkenyl group having 2 to 7 carbon atoms, an alkenyloxy group, R ^p represents a linear alkyl group having 1 to 7 carbon atoms or a linear alkenyl group having 2 to 7 carbon atoms, X ^a and X ^b represent a hydrogen atom or a fluorine atom, p5, p6, p7 and p8 each independently represent 0 or 1, p9 and p10 each independently represent 0, 1 or 2, p9 and The sum of p10 is 1 or 2, and M ^f and M ^g , M ^h and M ⁱ , M ^j and M ^k , M ^l and M ^m , and M ⁿ are each independently a single bond, —CH ₂ CH ₂ -, - CH = CH -, - OCH 2 -, - CH 2 O -, - OCF 2 -, - CF 2 O- or -COO- the stands, M ^o is a single bond or -CH ₂ CH ₂ - and represent , G ^e , G ^f , G ^g , G ^h , G ⁱ and G ^j are each independently substituted with a trans-1,4-cyclohexylene group or 1 to 2 fluorine atoms, 1,4 -Represents a phenylene group, and when there are a plurality of G ⁱ , G ^j , M ⁿ and ^Mo , they may be the same or different.) You may contain.

In the general formula (IV) to general formula (VIII), R ^g , R ⁱ , R ^k , R ^m and R ^p are preferably linear alkyl groups having 2 to 7 carbon atoms. R ^h , R ^j , R ⁿ and R ^o are preferably a linear alkyl group having 1 to 5 carbon atoms and a linear alkoxyl group. R ^l is preferably a linear alkyl group having 1 to 3 carbon atoms. M ^f and M ^g , M ^h and M ⁱ , M ^j and M ^k , M ^l and M ^m are each independently a single bond, —CH ₂ CH ₂ —, —CH═CH—, —OCH ₂ —, — Represents CH ₂ O—, —OCF ₂ —, —CF ₂ O— or —COO—, preferably one is a single bond and the other is a single bond, —CH ₂ CH ₂ — or —COO—. It is preferable. M ⁿ is preferably a single bond, —CH ₂ CH ₂ —, —CH ₂ O— or —CF ₂ O—.

In the liquid crystal composition of the present invention thus obtained, the nematic phase upper limit temperature (T _NI ) is 70 ° C. or higher, more preferably 75 ° C. or higher, and the nematic phase lower limit temperature (T _{> N 2} ) is −20 ° C. or lower.

  In the present invention, production examples of the compound represented by the general formula (1-1) are given below. Of course, the gist and scope of the present invention are not limited by these production examples.

  (Production method 1) General formula (IX)

(式中、R^a、M^p、G^aおよびp1は一般式(I-1)におけると同じ意味を表す。)で表されるカルボン酸に塩化チオニル、臭化チオニル、三塩化リン、五塩化リンあるいは三臭化リンなどを作用させて、一般式(X)

(Wherein R ^a , M ^p , G ^a and p1 have the same meaning as in general formula (I-1).) Thionyl chloride, thionyl bromide, phosphorus trichloride, pentachloride General formula (X) by the action of phosphorus or phosphorus tribromide

(式中、R^a、M^p、G^aおよびp1は一般式(I-1)におけると同じ意味を表し、Xは塩素、臭素などのハロゲン基を表す。)で表される酸ハロゲン化物を得る。得られた一般式(X)で表される酸ハロゲン化物と一般式(XI)

(Wherein R ^a , M ^p , G ^a and p1 have the same meaning as in general formula (I-1), and X represents a halogen group such as chlorine and bromine). obtain. The obtained acid halide represented by the general formula (X) and the general formula (XI)

(Wherein R ^b , M ^a , G ^b and p2 have the same meaning as in general formula (I-1)), naphthol represented by triethylamine, pyridine, diazabicyclo [2.2.2] octane, 4- By reacting in the presence of a base such as (dimethylamino) pyridine, general formula (I-1)

で表される化合物を得ることができる。

Can be obtained.

  (Production Method 2) Carboxylic acid represented by general formula (IX)

(式中、R^a、M^p、G^aおよびp1は一般式(I-1)におけると同じ意味を表す。)と一般式(XI)

(Wherein R ^a , M ^p , G ^a and p1 have the same meaning as in general formula (I-1)) and general formula (XI)

(式中、R^b、M^a、G^bおよびp2は一般式(I-1)におけると同じ意味を表す。)で表されるナフトールをアゾジカルボン酸エステル、トリフェニルホスフィン存在下、反応させることにより、一般式(I-1)

(Wherein R ^b , M ^a , G ^b and p2 have the same meanings as in general formula (I-1)), and reacting in the presence of azodicarboxylic acid ester and triphenylphosphine. According to general formula (I-1)

で表される化合物を得ることもできる。

The compound represented by these can also be obtained.

  (Production Method 2) Carboxylic acid represented by general formula (IX)

(式中、R^a、M^p、G^aおよびp1は一般式(I-1)におけると同じ意味を表す。)と一般式(XI)で表されるナフトール

(Wherein R ^a , M ^p , G ^a and p1 have the same meaning as in general formula (I-1)) and naphthol represented by general formula (XI)

(式中、R^b、M^a、G^bおよびp2は一般式(I-1)におけると同じ意味を表す。)をジシクロヘキシルカルボジイミドなどの脱水縮合剤およびトリエチルアミン、ピリジン、ジアザビシクロ[2.2.2]オクタン、4-(ジメチルアミノ)ピリジンなどの塩基存在下、反応させることにより、一般式(I-1)

(Wherein R ^b , M ^a , G ^b and p2 represent the same meaning as in general formula (I-1).) By reacting in the presence of a base such as 4- (dimethylamino) pyridine, general formula (I-1)

で表される化合物を得ることもできる。

The compound represented by these can also be obtained.

EXAMPLES Hereinafter, although an Example is given and this invention is further explained in full detail, this invention is not limited to these Examples. The structure of the compound was confirmed by nuclear magnetic resonance spectrum (NMR), mass spectrum (MS) and the like. Further, “%” in the compositions of the following Examples and Comparative Examples means “mass%”.
The following abbreviations are used in compound descriptions.
Me: methyl group
Et: ethyl group
Pr: Propyl group
Bu: Butyl group
Pen: Butyl group
DCC: Dicyclohexylcarbodiimide
DMAP: 4- (dimethylamino) pyridine
Example 1 Synthesis of 6-butoxy-3,4,5-trifluoronaphthalen-2-yl (IA) trans-4-propylcyclohexanecarboxylate (IA)

To a solution of 6-butoxy-3,4,5-trifluoro-2-naphthol (15.0 g) in dichloromethane (100 mL), trans-4-propylcyclohexanecarboxylic acid (9.5 g), dicyclohexylcarbodiimide (12.6 g), 4- (dimethylamino) pyridine (8.1 g) Then, the mixture was vigorously stirred at room temperature for 20 hours. The precipitated crystals were filtered through celite, water was added, and the organic layer was separated. The aqueous layer was extracted with dichloromethane, and the collected organic layer was washed with 3 M hydrochloric acid, water, saturated aqueous sodium hydrogen carbonate solution and saturated brine in that order, and dried over anhydrous sodium sulfate. The solvent was distilled off to obtain a pale yellow solid. Purification using a column (silica gel, toluene), distillation under reduced pressure (270-278 ° C., 1.3 KPa), purification using a column (silica gel, toluene), and recrystallization (hexane / toluene) 13.3 g was obtained.
Purity 99.9% (GC)
Phase transition temperature (℃) Cry 99.5 N 127 Iso
¹ H-NMR (400 MHz, CDCl ₃ ) δ: 0.88 1.37 (m, 7 H), 0.90 (t, J = 7.3 Hz, 3 H), 0.99 (t, J = 7.3 Hz, 3 H), 1.50 1.62 (m, 4 H), 1.78 1.91 (m, 4 H), 2.16 2.20 (m, 2 H), 2.54 2.60 (m, 1 H), 4.17 (t, J = 6.3 Hz, 2 H), 7.24 7.30 ( m, 2 H), 7.45 (d, J = 9.0 Hz, 1 H)

Example 2 Synthesis of trans-4- (trans-4-propylcyclohexyl) cyclohexanecarboxylic acid 6-butoxy-3,4,5-trifluoronaphthalen-2-yl (IB) Trans-4- in Example 1 By using trans-4- (trans-4-propylcyclohexyl) cyclohexanecarboxylic acid instead of propylcyclohexanecarboxylic acid, trans-4- (trans-4-propylcyclohexyl) cyclohexanecarboxylic acid 6-butoxy-3,4 Thus, 5-trifluoronaphthalen-2-yl was obtained.
Phase transition temperature (℃) Cry 131 N 272 Iso
¹ H-NMR (400 MHz, CDCl ₃ ) δ: 0.81 1.16 (m, 11 H), 0.88 (t, J = 7.3 Hz, 3 H), 0.99 (t, J = 7.6 Hz, 3 H), 1.26 1.33 (m, 2 H), 1.49 1.63 (m, 4 H), 1.71 1.89 (m, 8 H), 2.19 2.21 (m, 2 H), 2.51 2.59 (m, 1 H), 4.18 (t, J = 6.6 Hz, 2 H), 7.24-7.30 (m, 2 H), 7.46 (d, J = 9.0 Hz, 1 H)
(Example 3) Preparation of liquid crystal composition (1)
Host liquid crystal composition comprising the following composition (H)

を調製した。ここで(H)の物性値は以下の通りである。

Was prepared. Here, the physical properties of (H) are as follows.

Nematic phase upper limit temperature (T _NI ): 103.2 ℃
Dielectric anisotropy (Δε): 0.03
Refractive index anisotropy (Δn): 0.099
A liquid crystal composition (MA) comprising 90% of the base liquid crystal (H) and 10% of the compound (IA) obtained in Example 1 was prepared. The physical properties of this composition are as follows.
Nematic phase upper limit temperature (T _NI ): 104.9 ℃
Dielectric anisotropy (Δε): −0.61
Refractive index anisotropy (Δn): 0.103
In the liquid crystal composition (M-1) containing the compound (IA) of the present invention, the dielectric anisotropy (Δε) was greatly reduced to a negative value as compared with the base liquid crystal (H). This shows that the compound (IA) of the present invention has a negative dielectric anisotropy and an extremely large absolute value.

  Further, when the voltage holding ratio of the liquid crystal composition (M-A) was measured at 80 ° C., the voltage holding ratio of the host liquid crystal composition (H) was as high as 98% or more. This shows that the compound (I-A) of the present invention can be sufficiently used as a liquid crystal display material from the viewpoint of stability.

(Example 4) Preparation of liquid crystal composition (2)
A liquid crystal composition (MB) comprising 90% of the base liquid crystal (H) prepared in Example 3 and 10% of the compound (IB) obtained in Example 2 was prepared. The physical properties of this composition are as follows.
Nematic phase upper limit temperature (T _NI ): 117.8 ℃
Dielectric anisotropy (Δε): −0.56
Refractive index anisotropy (Δn): 0.103
In the liquid crystal composition (MB) containing the compound (IB) of the present invention, the dielectric anisotropy (Δε) was greatly reduced to a negative value as compared with the base liquid crystal (H). This shows that the compound (IB) of the present invention has a negative dielectric anisotropy and an extremely large absolute value.
Further, when the voltage holding ratio of the liquid crystal composition (MB) was measured at 80 ° C., it showed a high value of 98% or more with respect to the voltage holding ratio of the host liquid crystal composition (H). This shows that the compound (IB) of the present invention can be sufficiently used as a liquid crystal display material from the viewpoint of stability.

(Comparative Example 1) Preparation of liquid crystal composition (3)
90% of the base liquid crystal (H) prepared in Example 3 and the compound described in Patent Document 1 (IC)

10％からなる液晶組成物(M-C)を調製した。この組成物の物性値は以下の通りである。
ネマチック相上限温度(T_N-I)： 109.6℃
誘電率異方性(Δε)： −0.42
屈折率異方性(Δn)： 0.099
特許文献1記載の化合物 (I-C)を含有する液晶組成物(M-C)は、実施例3記載の液晶組成物(M-A) および実施例4記載の液晶組成物(M-B)と比べ、誘電率異方性の絶対値が小さく、またネマチック相上限温度(T_N-I)も低下したことがわかる。

A liquid crystal composition (MC) consisting of 10% was prepared. The physical properties of this composition are as follows.
Nematic phase upper limit temperature (T _NI ): 109.6 ℃
Dielectric anisotropy (Δε): −0.42
Refractive index anisotropy (Δn): 0.099
The liquid crystal composition (MC) containing the compound (IC) described in Patent Document 1 is more anisotropic than the liquid crystal composition (MA) described in Example 3 and the liquid crystal composition (MB) described in Example 4. It can be seen that the absolute value of the property is small and the nematic phase upper limit temperature (T _NI ) is also lowered.

(Comparative Example 2) Preparation of liquid crystal composition (4)
90% of the base liquid crystal (H) prepared in Example 3 and the compound described in Patent Document 4 (ID)

10％からなる液晶組成物(M-D)を調製した。この組成物の物性値は以下の通りである。

A liquid crystal composition (MD) consisting of 10% was prepared. The physical properties of this composition are as follows.

Nematic phase upper limit temperature (T _NI ): 113.1 ℃
Dielectric anisotropy (Δε): −0.53
Refractive index anisotropy (Δn): 0.104
The liquid crystal composition (MD) containing the compound (ID) described in Patent Document 1 is more anisotropic than the liquid crystal composition (MA) described in Example 3 and the liquid crystal composition (MB) described in Example 4. It can be seen that the absolute value of the property is small and the nematic phase upper limit temperature (T _NI ) is also lowered.

(Example 5) Preparation of liquid crystal composition (5)
A liquid crystal composition (ME) having the following composition was prepared.

液晶組成物(M-E)の物性値は以下の通りであった。
ネマチック相上限温度(T_N-I)： 95.4℃
誘電率異方性(Δε)： −3.12
屈折率異方性(Δn)： 0.097
ここで作製した組成物を用いて、電圧保持率を測定したところ80℃で98%と高い値を示し、優れた表示特性を示す液晶表示装置を作成することができた。

The physical properties of the liquid crystal composition (ME) were as follows.
Nematic phase upper limit temperature (T _NI ): 95.4 ℃
Dielectric anisotropy (Δε): −3.12
Refractive index anisotropy (Δn): 0.097
When the voltage holding ratio was measured using the composition prepared here, it was as high as 98% at 80 ° C., and a liquid crystal display device having excellent display characteristics could be produced.

(Example 6) Preparation of liquid crystal composition (6)
A liquid crystal composition (MF) having the following composition was prepared.

液晶組成物(M-F)の物性値は以下の通りであった。

The physical properties of the liquid crystal composition (MF) were as follows.

Nematic phase upper limit temperature (T _NI ): 108.6 ℃
Dielectric anisotropy (Δε): −2.88
Refractive index anisotropy (Δn): 0.094
When the voltage holding ratio was measured using the composition prepared here, it was as high as 98% at 80 ° C., and a liquid crystal display device having excellent display characteristics could be produced.

The liquid crystal composition, display element and compound of the present invention are useful as constituent members of liquid crystal display elements such as a vertical alignment system and IPS.

Claims (12)

Formula (I)

(In the formula, R ^a represents ^a linear alkyl group having 1 to 7 carbon atoms or a linear alkenyl group having 2 to 7 carbon atoms, and R ^b represents a linear alkyl group having 1 to 7 carbon atoms. Represents a straight-chain alkoxyl group having 1 to 7 carbon atoms, a straight-chain alkenyl group having 2 to 7 carbon atoms or a straight-chain alkenyloxy group having 2 to 7 carbon atoms, and M ^a and M ^p are respectively Independently represents a single bond, —CH ₂ CH ₂ —, —CH═CH—, —OCH ₂ —, —CH ₂ O—, —OCF ₂ —, —CF ₂ O—, —OCO— or —COO—. , G ^a and G ^b each independently represent a trans-1,4-cyclohexylene group or a 1,4-phenylene group, and p1 and p2 each independently represent 0 or 1. Contains one or more trifluoronaphthalene derivatives and has the general formula (II)

(In the formula, R ^c represents a linear alkyl group having 1 to 7 carbon atoms or a linear alkenyl group having 2 to 7 carbon atoms, and R ^d represents a linear alkyl group having 1 to 12 carbon atoms. Represents a linear alkenyl group having 2 to 12 carbon atoms, a linear alkoxyl group having 1 to 12 carbon atoms or a linear alkenyloxy group having 3 to 12 carbon atoms, p3 represents 0 or 1 , M ^b and M ^c each independently represents a single bond, —OCO—, —COO— or —CH ₂ CH ₂ —, and G ^c represents a trans-1,4-cyclohexylene group or -1,4-phenylene. A nematic liquid crystal composition having a negative dielectric anisotropy, containing one or more compounds represented by the formula: Formula (III)

(Wherein, R ^e represents a linear alkyl group having 1 to 7 carbon atoms, R ^f is a linear alkyl group, a linear alkoxyl group of 1 to 7 carbon atoms of 1 to 7 carbon atoms Or a linear alkenyloxy group having 3 to 7 carbon atoms, p4 represents 0 or 1, M ^d and ^Me are each independently a single bond, —CH ₂ CH ₂ —, —CH═CH— , -OCH _2- , -CH ₂ O-, -OCF _2- , -CF ₂ O-, -OCO- or -COO-, G ^d is a trans-1,4-cyclohexylene group or 1 to 2 2. The liquid crystal composition according to claim 1, wherein the liquid crystal composition contains one or more compounds represented by the formula: General formula (IV), general formula (V), general formula (VI), general formula (VII) and general formula (VIII)

(Wherein R ^g , R ⁱ , R ^k and R ^m each independently represents a linear alkyl group having 1 to 7 carbon atoms, and R ^h , R ^j and R ⁿ are each independently carbon. Represents a linear alkyl group having 1 to 7 atoms, a linear alkoxyl group having 1 to 7 carbon atoms, or a linear alkenyloxy group having 3 to 7 carbon atoms, and R ^l represents 1 to 7 carbon atoms. R ^o represents a linear alkyl group having 1 to 7 carbon atoms, a linear alkoxyl group having 1 to 7 carbon atoms, or a linear alkenyl group having 2 to 7 carbon atoms. Represents a linear alkenyloxy group having 3 to 7 carbon atoms, R ^p represents a linear alkyl group having 1 to 7 carbon atoms or a linear alkenyl group having 2 to 7 carbon atoms, and X ^a And X ^b each independently represent a hydrogen atom or a fluorine atom, p5, p6, p7 and p8 each independently represent 0 or 1, p9 and p10 each independently represent 0, 1 or 2, the sum of p9 and p10 is 1 or 2, and M ^f , M ^g , M ^h , M ⁱ , M ^j , M ^k , M ^l , M ^m and M ⁿ are each independently _{bond, -CH 2 CH 2 -, -} CH = CH -, - OCH 2 -, - CH 2 O -, - OCF 2 -, - CF 2 O -, - represents OCO- or -COO-, M ^o is Represents a single bond or —CH ₂ CH ₂ —, and G ^e , G ^f , G ^g , G ^h , G ⁱ and G ^j are each independently a trans-1,4-cyclohexylene group or 1 to 2 fluorine atoms Represents a 1,4-phenylene group which may be substituted by, and when there are a plurality of G ⁱ , G ^j , M ⁿ and ^Mo , they may be the same or different. The liquid crystal composition according to claim 1 or 2, which contains one or more compounds selected from the group consisting of the above compounds. Contains two or more compounds represented by general formula (III), represented by general formula (IV), general formula (V), general formula (VI), general formula (VII) and general formula (VIII) The liquid crystal composition according to claim 3, comprising two or more selected from the group of compounds. The nematic phase upper limit temperature is 70 ° C or higher, the nematic phase lower limit temperature is -20 ° C or lower, and the content of the compound represented by the general formula (I) is in the range of 1 to 50% by mass. 5. The liquid crystal composition according to any one of 4. A liquid crystal display device using the liquid crystal composition according to claim 1. 7. The liquid crystal display element according to claim 6, which is active matrix driven. The liquid crystal display element according to claim 7, which is displayed in a vertical alignment mode. Formula (I-1)

(In the formula, R ^a represents ^a linear alkyl group having 1 to 7 carbon atoms or a linear alkenyl group having 2 to 7 carbon atoms, and R ^b represents a linear alkyl group having 1 to 7 carbon atoms. Represents a straight-chain alkoxyl group having 1 to 7 carbon atoms, a straight-chain alkenyl group having 2 to 7 carbon atoms or a straight-chain alkenyloxy group having 2 to 7 carbon atoms, and M ^a and M ^p are respectively Independently represents a single bond, —CH ₂ CH ₂ —, —CH═CH—, —OCH ₂ —, —CH ₂ O—, —OCF ₂ — or —CF ₂ O—, wherein G ^a and G ^b are each And independently represents a trans-1,4-cyclohexylene group or a 1,4-phenylene group, and p1 and p2 each independently represents 0 or 1.). In the general formula (I-1), R ^a represents a linear alkyl group having 1 to 5 carbon atoms, and R ^b is a linear alkyl group having 1 to 5 carbon atoms or 1 to 5 carbon atoms. The compound according to claim 9, which represents a linear alkoxyl group. In the general formula (I-1), M ^a and M ^p is a single bond or -CH ₂ CH ₂ - The compound of claim 9, wherein representing the. The compound according to claim 9, wherein, in general formula (I-1), p1 is 0 or 1, and p2 is 0.