JP2631876B2 - Liquid crystal material - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a liquid crystal compound useful for a display element or an electro-optical element and a liquid crystal composition containing the same.

At present, a display element using a liquid crystal material is a light-receiving display method, and has features such as low power consumption and a thin display device, and is widely used in practice. On the other hand, EL (electroluminescence) and plasma displays, which use a light-emitting display method that can display a large screen and have a high-speed response, are also being actively developed.

[Conventional technology]

Most of the liquid crystals used in the display elements so far are nematic liquid crystals, and the mainstream liquid crystal is a TN (Twisted Nematic) type. The TN display method has advantages such as small size and low power consumption, but also has a disadvantage that the response speed of image display is slow. Utilizing the features of liquid crystal display elements such as light receiving type and low power consumption,
In addition, development of a new liquid crystal display method is indispensable in order to ensure responsiveness comparable to that of a light-emitting display.
As one of the attempts, a display device using the optical switching phenomenon of ferroelectric liquid crystal has been proposed.

Ferroelectric chiral smectic C phase which is the classification nomenclature molecular arrangement, chiral smectic I phase, chiral smectic F phase, chiral smectic G phase and chiral smectic H phase (hereinafter respectively S _C ^* phase, S _I ^* phase,
S _F ^* phase, S _G ^* phase and S _H ^* abbreviated as phase) expressed in, strong responses following equation based the dielectric [a] τ = η / Ps · E [a] (in the formula tau response time , Η is the viscosity of the liquid crystal material, Ps is the spontaneous polarization, and E is the electric field.
It is possible to obtain a display element that can respond up to μs.

Current ferroelectric liquid crystal compounds have a helical structure, similar to cholesteric liquid crystals. It is necessary to unwind this spiral for the optical switching phenomenon to appear in the ferroelectric liquid crystal. As one of the unwinding methods, there is a method of manufacturing a cell in which the cell gap is controlled to a helical pitch P or less. However, since the helical pitch of many compounds is 1 to 3 μm, it is difficult with the current cell manufacturing technology. On the other hand, a method of unwinding the helix is considered from the viewpoint of the compounding technique of the liquid crystal compound (JP-A No.
61-195187). This is a method by mixing a compound having a smectic C phase with a ferroelectric smectic liquid crystal compound or a composition thereof. According to this method, a method of blending ferroelectric smectic liquid crystals (Japanese Patent Application No.
-186312, and JP-A-61-174294), which is important for obtaining a practical liquid crystal composition.

[Problems to be solved by the invention]

Therefore, as a compound having a smectic C phase, the temperature range in which the smectic C phase is shown is wide, the upper limit temperature is high, it is well mixed with a ferroelectric smectic liquid crystal compound, and it is chemically, thermally and light stable. It is desired to have various properties such as that.

[Means for solving the problem]

The present inventors have assiduously studied from the above viewpoint, excellent stability, well mixed with a ferroelectric smectic liquid crystal compound, a wide temperature range showing a smectic C phase, a high liquid crystal compound having a high upper limit temperature and The present invention has been found a liquid crystal composition containing

That is, the present invention provides a compound represented by the general formula [I]: (Wherein R ¹ represents a linear alkyl group or a linear alkoxy group having 1 to 20 carbon atoms, and R ² represents an alkoxy group having 1 to 20 carbon atoms (provided that
Excluding optically active groups), and Y is And Z is a group —C≡C— or a group —CH ₂ CH ₂ —, and Q is And X represents a hydrogen atom or a halogen atom, respectively).

The invention also provides a liquid crystal composition comprising at least one compound represented by the above general formula [I].

Specific examples of typical examples of the compound represented by the general formula [I] can be divided into the following groups according to the combination of Y, Q and Z in the formula. (In the above formula, R ¹ , R ² and X have the same meaning as described above.) The outline of the method for producing the compound of the present invention is as follows.

(Wherein R ¹ , R ² X and Y have the same meaning as described above,
Represents triethylamine. [Action] The compound of the present invention has the following action and characteristics.

First, in an atmosphere containing moisture, since there is no group that can be easily decomposed or a group that isomerizes by light, it is very stable against moisture and light.

Secondly, many of the compounds of the present invention, alone or with smectic C
Since the temperature range showing the phase is wide, the compounds of the present invention,
By mixing the compound of the present invention with a compound having an existing smectic C phase, for example, an ester type, a biphenyl type, a pyrimidine type or the like, the temperature range showing the smectic C phase can be extended to a wide range including room temperature. Therefore, practically, even if the ferroelectric chiral smectic liquid crystal compound to be mixed has a narrow temperature range exhibiting ferroelectricity, the compound can be mixed, so that the range in which the compound can be selected is widened.
It is also possible to mix the compound of the present invention with an optically active compound which does not exhibit ferroelectricity by itself.

〔Example〕

Hereinafter, the present invention will be described by way of examples. In the examples,% represents% by weight.

Production Example 1 Synthesis of 4-alkoxyphenylacetylene [B] A 500-ml three-necked flask equipped with a stirrer, a thermometer and a reflux condenser was charged with 64 mmol of 4-alkoxybromobenzene and 3-methyl-1-methyl-2-nitrogen in a nitrogen stream. Butyn-3-ol 5.91
g (70 mmol), triphenylphosphine 270 mg, dichlorobis (triphenylphosphine) palladium catalyst 140 mg
(0.20 mmol) and 60 ml of triethylamine were charged and dissolved by stirring, and 45 mg of copper iodide was added. After stirring at room temperature for 3 hours,
The mixture was gradually heated, and the internal temperature was adjusted to 80 ° C. in 30 minutes. The reaction was performed at this temperature for 10 hours. After the reaction, the temperature was returned to room temperature, triethylamine was distilled off under reduced pressure, 300 ml of ether was added to the residue, washed with water, and dried over anhydrous sodium sulfate. After filtration,
The ether was distilled off, and the residue was subjected to silica gel column chromatography (100 g of 200-mesh silica gel, developing solvent: benzene) to obtain a compound [A] of the following formula as an intermediate compound (yield 70 to 87%).

In a 300 ml three-necked flask equipped with a stirrer, a thermometer and a distillation apparatus, 57.8 mmol of the above compound (a) in a nitrogen stream,
120 ml of anhydrous toluene and sodium hydride (60%
(Nujol dispersant) 200 mg and stirred at room temperature for 30 minutes. The mixture was gradually heated and required 30 minutes to bring the internal temperature to 70 ° C. Reflux of acetone (by-product) started, and distillation started with toluene. The reaction was continued by further heating until the distillation temperature reached the boiling point of toluene. It took 2 hours during this time to distill off 60 ml of the solvent. After the reaction was completed, the temperature was returned to room temperature, 100 ml of benzene was added, washed with water, and dried over anhydrous sodium sulfate. After filtration, the organic solvent was distilled off, and the residue was subjected to silica gel column chromatography (silica gel 100 mesh of 200 mesh).
g, developing solvent: hexane) to give 4-alkoxyphenylacetylene [B] in Table 1 in a yield of 85 to 95%. Its structure was confirmed by IR and NMR spectra.

 The results are shown in Table 1.

Production Example 2 Synthesis of p-bromophenyl-4-alkoxy (or alkyl) benzoate [C] 3.93 g (25 mmol) of p-bromophenol in a 100 ml three-necked flask equipped with a stirrer, thermometer and reflux condenser.
And 10 ml of anhydrous pyridine were charged and dissolved under stirring. A tetrahydrofuran solution containing 20 mmol of 4-alkoxy (or alkyl) benzoyl chloride is added to this pyridine solution.
ml was added under ice cooling. After returning the reaction temperature to room temperature, the mixture was brought to the reflux temperature and stirred for 8 hours. After completion of the reaction, benzene was added, and the mixture was washed with water, washed with 10% caustic soda in alkaline water, washed with water in that order, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, the residue was isolated and purified as crystals from ethanol, and the p-bromophenyl-4-alkoxy (or alkyl) benzoate [C] shown in Table 2 was obtained at a yield of 72 to 97%. Obtained.

Production Example 3 p-bromophenyl-4-alkoxy-3-
Synthesis of chlorobenzoate [C] Synthesis was performed under the same conditions as in Production Example 2 except that 20 mmol of 4-alkoxy-3-chlorobezoyl chloride was used instead of 29 mmol of 4-alkoxy (or alkyl) benzoyl chloride. p-Bromophenyl-4-alkoxy-3-chlorobenzoate [C] was obtained in a yield of 82 to 91%.

 Table 2 shows the above results.

Production Example 4 p-Alkoxy (or alkyl) phenyl-
Synthesis of 4-bromobenzoate [C] In a 100 ml three-necked flask equipped with a stirrer, thermometer and reflux condenser, 18.2 mmol of p-alkoxy (or alkyl) phenol and 10 ml of anhydrous pyridine were charged and dissolved under stirring. did. To this pyridine solution, 20 ml of a tetrahydrofuran solution containing 4.30 g (19.6 mmol) of 4-bromobenzoyl chloride was added under ice cooling. After returning the reaction temperature to room temperature,
It was brought to reflux temperature and stirred for 8 hours. After completion of the reaction, benzene was added, and the mixture was washed with water, washed with 10% caustic soda in alkaline water, washed with water in that order, and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure, and the residue was isolated and purified from ethanol to obtain p-alkoxy (or alkyl) phenyl-4-bromobenzoate [C] in Table 3 in a yield of 80 to 98%. .

Production Example 5 4'-alkoxy-3'-chlorophenyl-
Synthesis of 4-bromobenzoate [C] p-alkoxy (or alkyl) phenol 18.2 mmol
Instead of 4-alkoxy-3-chlorophenol 18.2mm
All were synthesized under the same conditions as in Production Example 4 except that ol was used.
4'-Alkoxy-3'-chlorophenyl-4 in Table 3
-Bromobenzoate [C] was obtained in a yield of 88-89%.

 Table 3 shows the above results.

Production Example 6 p-Alkoxy (or alkyl) phenyl-
Synthesis of 6-chloronicotinate [D] In a 100 ml three-necked flask equipped with a stirrer, thermometer and reflux condenser, 30 mmol of p-alkoxy (or alkyl) phenol and 20 ml of anhydrous pyridine were charged and dissolved under stirring. did. To this pyridine solution, 50 ml of a dichloroethane solution containing 35 mmol of 6-chloronicotinyl chloride was added under ice cooling. After returning the reaction temperature to room temperature, the mixture was heated to 40 ° C. and stirred for 8 hours. After the reaction, add benzene and wash with water, 10%
After washing with caustic soda in the order of alkaline water and water, it was dried over anhydrous sodium sulfate. The solvent is distilled off under reduced pressure,
The residue was isolated and purified from ethanol to obtain p-alkoxy (or alkyl) phenyl-6-chloronicotinate [D] in Table 4 in a yield of 88 to 95%.

Production Example 7 4'-alkoxy-3'-chlorophenyl-
Synthesis of 6-chloronicotinate [D] Instead of 30 mmol of p-alkoxy (or alkyl) phenol, 30 mmol of 4-alkoxy-3-chlorophenol
Were synthesized under the same conditions as in Production Example 6 except that the compound of formula (1) was used, and 4'-alkoxy-3'-chlorophenyl-6-
Chlornicotinate [D] was obtained in a yield of 83%.

 Table 4 shows the above results.

Example 1 4- [p-alkoxy (or alkyl) phenylcarbonyloxy] -4'-alkoxytolan [I
a] Synthesis of (when X = H) In a three-necked flask equipped with a stirrer, a thermometer, and a reflux condenser, the p-bromophenyl-4-alkoxy obtained in Production Example 2 in a nitrogen stream (or Alkyl) benzoate 4.
8 mmol, 4-alkoxyphenylacetylene 5.0 mmol obtained in Production Example 1, triphenylphosphine 65 mg, dichlorobis (triphenylphosphine) palladium catalyst 32
mg and 30 ml of triethylamine were charged and dissolved by stirring, and 6 mg of copper iodide was added. After stirring at room temperature for 2 hours, the mixture was gradually heated to 90 ° C. in 30 minutes. The reaction was carried out at this temperature for 16 hours. After the reaction, the temperature was returned to room temperature, triethylamine was distilled off under reduced pressure, 100 ml of ether was added to the residue, washed with water, and dried over anhydrous sodium sulfate. After filtration, ether was distilled off,
The residue was subjected to silica gel column chromatography (100 g of 200-mesh silica gel, developing solvent: benzene / hexane = 1/1) to isolate and purify. Recrystallization from hexane gave 4- [p-alkoxy (or alkyl) phenylcarbonyloxy] -4'-alkoxytolan [I] in Table 5 in 87-92% yield. The structure of each compound is
Confirmed by IR and NMR spectral data.

Example 2 4- (4 "-alkoxy-3"-chlorophenylcarbonyloxy-4'-alkoxytolan [Ia]
Synthesis of (when X = Cl) 4.8 mmol of p-bromophenyl-4-alkoxy-3-chlorobenzoate obtained in Production Example 3 was used instead of 4.8 mmol of p-bromophenyl-4-alkoxy (or alkoxy) benzoate. Synthesized under the same conditions as in Example 1 except for using 4- (4 ″ -alkoxy-3 ″ in Table 5.
-Chlorophenylcarbonyloxy) -4'-alkoxytolan [I] was obtained in a yield of 80 to 89%. The structure of each compound was confirmed by IR and NMR spectrum data.

Example (Compound No. 7) Table 5 shows the results together with the phase transition temperatures of the respective compounds obtained in Examples 1 and 2 above.

Example 3 4- [p-alkoxy (or alkyl) phenyloxycarbonyl] -4'-alkoxytolan [I
b] Synthesis of (when X = H) The p-alkoxy (or alkyl) phenyl-4-bromobenzoate 4.8 obtained in Production Example 4 was placed in a three-necked flask equipped with a stirrer, a thermometer, and a reflux condenser. mmol, 4-alkoxyphenylacetylene 5.0m obtained in Production Example 1
mol, 65 mg of triphenylphosphine, 32 mg of dichlorobis (triphenylphosphine) palladium catalyst and 30 ml of triethylamine were stirred and dissolved, and 6 mg of copper iodide was added. After stirring at room temperature for 2 hours, the mixture was gradually heated to 80 to 90 ° C in 30 minutes. The reaction was performed at this temperature for 10 hours. After the reaction, the temperature was returned to room temperature, triethylamine was distilled off under reduced pressure, 100 ml of ether was added to the residue, washed with water, and dried over anhydrous sodium sulfate. After filtration, ether was distilled off, and the residue was subjected to silica gel column chromatography (100 g of 200 mesh silica gel, developing solvent: benzene / hexane = 1 /
It was isolated and purified in 1). Recrystallized from hexane to give 4- [p-alkoxy (or alkyl) phenyloxycarbonyl] -4'-alkoxytolan [I] in Table 6.
In a yield of 83-92%. The structure of each compound is IR and NMR
Confirmed by spectral data.

Example 4 4- (4 "-alkoxy-3" -chlorophenyloxycarbonyl) -4'-alkoxytolan [I
b] Synthesis of (when X = Cl) 4′-alkoxy-3′-chlorophenyl-4-bromo obtained in Preparation Example 5 instead of 4.8 mmol of p-alkoxy (or alkyl) phenyl-4-bromobenzoate Synthesized under the same conditions as in Example 3 except that 4.8 mmol of benzoate was used, and the 4- (4 ″ -alkoxy-
3 "-Chlorophenyloxycarbonyl) -4'-alkoxytolan [I] was obtained in a yield of 81 to 91%. The structure of each compound was confirmed by IR and NMR spectral data.

Example (Compound No. 20) Table 6 shows the results together with the phase transition temperatures of the respective compounds obtained in Examples 3 and 4.

Example 5 p-Alkoxy (or alkyl) phenyl-
Synthesis of 6- (p-alkoxyphenyl) ethynyl nicotinate [Ic] (when X = H) In a reaction vessel, the p-
4.8 mmol of alkoxy (or alkyl) phenyl-6-chloronicotinate, 5.0 mmol of 4-alkoxyphenylacetylene obtained in Production Example 1, triphenylphosphine 6
5 mg, 32 mg of a dichlorobis (triphenylphosphine) palladium catalyst and 30 ml of triethylamine were charged, dissolved by stirring, and 6 mg of copper iodide was added. After stirring at room temperature for 2 hours,
The mixture was gradually heated to 80 ° C. in 30 minutes. The reaction was carried out at this temperature for 16 hours. After the reaction, the temperature was returned to room temperature, triethylamine was distilled off under reduced pressure, 100 ml of ether was added to the residue, washed with water, and dried over anhydrous sodium sulfate. After filtration, ether was distilled off, and the residue was isolated and purified by silica gel column chromatography (100 g of 200-mesh silica gel, developing solvent: benzene). Recrystallized from hexane to obtain p-alkoxy (or alkyl) phenyl-6 shown in Table 7.
-(P-alkoxyphenyl) ethynyl ecotinate
Obtained in 80-84% yield. The structure of each compound is IR and NMR
Confirmed by spectral data.

Example (Compound No. 22) Example 6 4'-Alkoxy-3'-chlorophenyl-
Synthesis of 6- (p-alkoxyphenyl) ethynyl nicotinate [Ic] (when X = Cl) 4 obtained in Preparation Example 7 in place of 4.8 mmol of p-alkoxy (or alkyl) phenyl-6-chloronicotinate Synthesized under the same conditions as in Example 5 except that 4.8 mmol of '-alkoxy-3'-chlorophenyl-6-chloronicotinate was used.
Chlorophenyl-6- (p-alkoxyphenyl) ethynylnicotinate was obtained in 79-85% yield. The structure of each compound was confirmed by IR and NMR spectrum data.

Example (Compound No. 26) Table 7 shows the results together with the phase transition temperatures of the compounds obtained in Examples 5 and 6 above.

Example 7 1- (p-Alkoxyphenyl) -2-4 '
-Synthesis of [p-alkoxy (or alkyl) phenylcarbonyloxy] phenyl ethane [Id] (when X = H) In a flask equipped with a stirrer, thermometer, reflux condenser, and rubber balloon storing hydrogen gas. 4- [p obtained in Example 1
-Alkoxy (or alkyl) phenylcarbonyloxy] -4'-alkoxytolan (4.4 mmol), 5% palladium-carbon catalyst (500 mg), and ethyl acetate (10 ml) were charged, and the mixture was reacted at room temperature after purging with hydrogen gas. The progress of the reaction was examined with a thin-layer chromatography chip. Although the reaction was almost completed in about 1 hour, the reaction was continued in a hydrogen atmosphere for another 2 hours. After the reaction, the catalyst was removed with a glass filter covered with a filter aid, and ethyl acetate was distilled off under reduced pressure. The reaction crude product was purified by silica gel column chromatography (50 g of 200 mesh silica gel, developing solvent: benzene),
In Table 8, 1- (p-alkoxyphenyl) 2-4'-
[P-Alkoxy (or alkyl) phenylcarbonyloxy] phenylethane [I] was obtained in 90-97% yield. The structure of each compound was confirmed by IR and NMR spectrum data.

Example 8 1- (p-Alkoxyphenyl) -2-4 '
Synthesis of (4 "-alkoxy-3" -chlorophenylcarbonyloxy) phenylethane [Id] (when X = Cl) 4- [p-alkoxy (or alkyl) phenylcarbonyloxy] -4'-alkoxytolan 4.4 mmol Was synthesized under the same conditions as in Example 7 except that 4.4 mmol of 4- (4 "-alkoxy-3" -chlorophenylcarbonyloxy) -4'-alkoxytolan obtained in Example 2 was used instead of 1- (p-Alkoxyphenyl)-in the table
2-4 '-(4 "-Alkoxy-3" -chlorophenylcarbonyloxy) phenylethane [I] was obtained in a yield of 91 to 95%. The structure of each compound was confirmed by IR and NMR spectrum data.

Example (Compound No. 35) Table 8 shows the results together with the phase transition temperatures of the compounds obtained in Examples 7 and 8.

Example 9 1- (p-alkoxyphenyl) -2-4 '
Synthesis of-[p-alkoxy (or alkyl) phenyloxycarbonyl] phenylethane [Ie] (when X = H) 4- [p-alkoxy (or alkyl) phenylcarbonyloxy] -4'-alkoxy of Example 7 Tran 4.
4- [p-Alkoxy (or alkyl) phenyloxycarbonyl] -4'- obtained in Example 3 instead of 4 mmol
All were synthesized under the same conditions as in Example 7 except that 4.4 mmol of alkoxytolan was used. 1- (p-Alkoxyphenyl) -2-4 '-[p-alkoxy (or alkyl) phenyloxycarbonyl] in Table 9 Phenylethane [I]
Was obtained in 90-98% yield. The structure of each compound is IR and NMR
Confirmed by spectral data.

Example 10 1- (p-Alkoxyphenyl) -2-4 '
Synthesis of-(4 "-alkoxy-3" -chlorophenyloxycarbonyl) phenylethane [Ie] (when X = Cl) 4- [p-alkoxy (or alkyl) phenylcarbonyloxy] -4 'of Example 7 -Alkoxy tran 4.
Example 7 except that 4.4 mmol of 4- (4 "-alkoxy-3" -chlorophenyloxycarbonyl) -4'-alkoxytolan obtained in Example 4 was used instead of 4 mmol.
1- (p-alkoxyphenyl) -2-4 '-(4 "-alkoxy-3" -chlorophenyloxycarbonyl) phenylethane [I] in Table 9
Obtained in 93-98% yield. The structure of each compound was confirmed by IR and NMR spectrum data.

Example (Compound No. 48) Table 9 shows the results together with the phase transition temperatures of the compounds obtained in Examples 9 and 10.

Example 11 p-Alkoxy (or alkyl) phenyl-
Synthesis of 6-β- (p-alkoxyphenyl) ethyl nicotinate [If] (when X = H) 4- [p-alkoxy (or alkyl) phenylcarbonyloxy] -4′-alkoxytolan 4 of Example 7 .
Synthesis was performed under the same conditions as in Example 7 except that 4.4 mmol of the p-alkoxy (or alkyl) phenyl-6- (p-alkoxyphenyl) ethylnylnicotinate obtained in Example 5 was used instead of 4 mmol. The p-alkoxy (or alkyl) phenyl-6-β- (p-alkoxy) ethyl nicotinate [I] in the table was obtained in 91-95% yield. The structure of each compound was confirmed by IR and NMR spectrum data.

Example (Compound No. 50) Example 12 4'-Alkoxy-3'-chlorophenyl-
Synthesis of 6-β- (p-alkoxyphenyl) ethyl nicotinate [If] (when X = Cl) 4- [p-alkoxy (or alkyl) phenylcarbonyloxy] -4′-alkoxytolan 4 of Example 7 .
4'-Alkoxy-3 'obtained in Example 6 instead of 4 mmol
-Chlorophenyl-6- (p-alkoxyphenyl) ethynyl nicotinate Synthesized under the same conditions as in Example 7 except that 4.4 mmol was used.
3′-Chlorophenyl-6-β (p-alkoxyphenyl) ethyl nicotinate [I] was obtained in 91-95% yield. The structure of each compound was confirmed by IR and NMR spectrum data.

Example (Compound No. 54) Table 10 shows the results together with the phase transition temperatures of the compounds obtained in Examples 11 and 12.

Example 13 (Reference Example) 4-ethyl-4'-cyanobiphenyl 20% 4-pentyl-4'-cyanobiphenyl 40% 4-octyloxy-4'-cyanobiphenyl 25% 4-pentyl-4'-cyanobiter A nematic liquid crystal composition consisting of 15% phenyl is coated with polyvinyl alcohol (PVA), its surface is rubbed, a parallel alignment treatment is performed, and the liquid crystal composition is injected into a cell having a transparent electrode in which the electrode interval is controlled to 10 μm, and the TN liquid crystal composition is injected. When a display cell was formed and observed under a polarizing microscope, it was observed that a reverse twist domain was generated.

Next, in the above nematic liquid crystal composition, an optically active liquid crystalline compound represented by the following formula: When 1% of the compound represented by the formula [Compound No. 15] was added and observed in a TN cell in the same manner, the reverse twist domain was eliminated and a uniform nematic phase was observed.

Examples 14 to 16 A liquid crystal composition was prepared using the liquid crystal compound of the present invention and a known smectic liquid crystal compound.
A composition having a phase and a wide temperature range was obtained (Example 1).
Four).

When a known ferroelectric liquid crystal compound was mixed with the liquid crystal composition obtained in Example 14 (Example 15) or an optically active compound was mixed (Example 16), a ferroelectric substance having a relatively long helical pitch P was obtained. A chiral smectic liquid crystal composition was obtained.

 Table 11 shows the above results.

[Effects of the Invention] Many of the compounds of the present invention have a wide temperature range in which a smectic C phase is exhibited. Therefore, a smectic liquid crystal composition having a wide temperature range in which ferroelectricity is exhibited by adding a ferroelectric smectic liquid crystal or an optically active compound. Is obtained. Such effects are achieved by the present invention.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical indication location C09K 19/20 9279-4H C09K 19/20 19/34 9279-4H 19/34 // G02F 1 / 13 500 G02F 1/13 500

Claims (2)

(57) [Claims] 1. A compound of the general formula [I]: (Wherein R ¹ represents a linear alkyl group or a linear alkoxy group having 1 to 20 carbon atoms, and R ² represents an alkoxy group having 1 to 20 carbon atoms (provided that
Excluding optically active groups), and Y is And Z is a group —C≡C— or a group —CH ₂ CH ₂ —, and Q is And X represents a hydrogen atom or a halogen atom, respectively). 2. A compound of the general formula [I]: (Wherein R ¹ represents a linear alkyl group or a linear alkoxy group having 1 to 20 carbon atoms, and R ² represents an alkoxy group having 1 to 20 carbon atoms (provided that
Excluding optically active groups), and Y is And Z is a group —C≡C— or a group —CH ₂ CH ₂ —, and Q is And X represents a hydrogen atom or a halogen atom, respectively).