JPH05201929A - Optically active compound and display element - Google Patents

Abstract

(57) [Summary] (Modified) [Objective] To provide an antiferroelectric liquid crystal material having three stable molecular alignment states excellent in high-speed response and a display device using the same. [Structure] General formula (I), for example, (R) -4′-decyloxybiphenyl-4-carboxylic acid-2-fluoro-4
An optically active compound such as-(1-trifluoromethyl-5-methoxypentyloxycarbonyl) phenyl ester, and a display device using the same. (R ¹ is an alkyl group or an alkoxyl group having 1 to 20 carbon atoms, R ² is an alkyl group having 1 to 12 carbon atoms, and n is 4 to 1
It is an integer of 2)

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel optically active compound. INDUSTRIAL APPLICABILITY The optically active compound of the present invention is useful as an antiferroelectric liquid crystal material exhibiting a chiral smectic C _A phase having three stable molecular alignment states with excellent fast response.

[0002]

2. Description of the Related Art Currently, display devices using liquid crystal compounds are
It is widely used from the viewpoints of its low voltage drivability, low power consumption, small size and thinness. Recently, a surface-stabilized ferroelectric liquid crystal device using a ferroelectric liquid crystal has been actively studied as a fast response liquid crystal device. This surface-stabilized ferroelectric liquid crystal device has two stable molecular alignment states. Switching between these two states is possible by applying a voltage equal to or higher than the polarization inversion threshold value of the element, and its response time is as fast as 10 to 100 μs order. The applied voltage is 0 in each state.
However, it ideally has a memory property of retaining the state when a voltage equal to or higher than the polarization inversion threshold immediately before that is applied. Utilizing these characteristics, researches on display elements such as computer displays and televisions, optical elements for optical information processing, and the like are being conducted.

However, the surface-stabilized ferroelectric liquid crystal device has the following problems. Since the two molecular alignment states possessed by the surface-stabilized ferroelectric liquid crystal element are both states in which spontaneous polarization exists, when an insulating material such as polyimide is used as the alignment film, the alignment film is dielectric Polarization occurred and when the applied voltage was set to 0, a reverse voltage equal to or higher than the polarization reversal threshold was applied to the liquid crystal, and switching to the other state occurred at a certain part in the electrode, which was obtained when the voltage was applied immediately before. In some cases, a uniform molecular orientation state cannot be maintained. That is, it may not exhibit the memory property that should be the property of the surface-stabilized ferroelectric liquid crystal device. Further, in this surface-stabilized ferroelectric liquid crystal device, it is easy to take a structure in which the smectic layer is bent, a so-called chevron structure.
It is difficult to obtain a good molecular orientation state. further,
In terms of durability, the device is apt to have alignment defects due to mechanical shock, and it is difficult to repair the defects once generated.

As a ferroelectric liquid crystal compound having an alkoxyalkyl group as a substituent of an optically active center, 4'-decyloxybiphenyl-4-carboxylic acid-4-[(1-
Trifluoromethyl-3-ethoxy) propyloxycarbonyl] phenyl ester (JP-A-64-3154) is known. On the other hand, as the antiferroelectric liquid crystal material exhibiting a chiral smectic C _A phase has three stable molecular arrangement states, 4'-octyloxy-biphenyl -
4-Carboxylic acid-4- [1- (trifluoromethyl) heptyloxycarbonyl] phenyl ester (Patent Document 2
No. 160748). An element using a composition composed of a tricyclic ester compound is used as a display element using an antiferroelectric liquid crystal (Japanese Patent Laid-Open No. 1-213).
No. 390) is known.

[0005]

DISCLOSURE OF THE INVENTION The present invention has a high-speed response that solves the problems of the conventional surface-stabilized ferroelectric liquid crystal device by making the molecular structure different from the conventionally known antiferroelectric liquid crystal material. It is intended to provide an antiferroelectric liquid crystal compound having excellent stability and having three stable molecular alignment states, and a display device using the liquid crystal compound.

[0006]

The present invention has the general formula (1)
A display element using the optically active compound represented by and the optically active compound represented by the general formula (1).

[0007]

[Chemical 3]

(In the formula, R ¹ is an alkyl group or an alkoxyl group having 1 to 20 carbon atoms, and R ² is 1 to 12 carbon atoms.
Is an alkyl group, and n is an integer of 4 to 12).

In the above general formula (1), R ¹ is an alkyl group or an alkoxyl group having 1 to 20 carbon atoms, specifically, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group. , Heptyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group,
Tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group, nonadecyl group, icosyl group, methoxy group, ethoxy group, propoxy group, butoxy group, pentyloxy group, hexyloxy group, heptyloxy group, octyloxy group Group, nonyloxy group, decyloxy group, undecyloxy group, dodecyloxy group, tridecyloxy group, tetradecyloxy group, pentadecyloxy group, hexadecyloxy group, heptadecyloxy group, octadecyloxy group, nonadecyloxy group, icosyloxy group Examples thereof include groups, which may be linear or branched.

In the above general formula (1), R ² is an alkyl group having 1 to 12 carbon atoms, specifically, methyl group, ethyl group, propyl group, butyl group, pentyl group, hexyl group, heptyl. Group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, which may be linear or branched. In addition, n is an integer of 4 to 12.

Specific examples of the compound represented by the general formula (1) of the present invention include the compounds shown in Tables 1 to 6 below.

[0012]

[Table 1]

[0013]

[Table 2]

(Production Method) The compound represented by the general formula (1) of the present invention can be produced by the method represented by the following reaction formula. Hereinafter, as illustrated by the reaction formula, in the formula,
R ¹ , R ² and n are the same as those defined in the general formula (1), and the number of () in the formula represents the compound in the upper row.

[0015]

[Chemical 4]

In the reaction step [I], 3-fluoro-4-benzyloxybenzoic acid and 1-trifluoromethylalkoxy alcohol are used, dicyclohexylcarbodiimide or the like is used as a dehydration condensation agent, and N, N-dimethyl-4 is used as a catalyst. -By using an organic base such as aminopyridine and using methylene chloride, chloroform or the like as a solvent,
Easy to implement.

The reaction step [II] is a debenzylation step and can be carried out by a known method such as hydrogenation at atmospheric pressure using palladium carbon or the like as a catalyst and ethanol, acetic acid or the like as a solvent. The reaction step [III] is 4'-
Alkyl (alkoxy) biphenyl-4-carboxylic acid and the compound obtained in the reaction step [II] are dehydrated and condensed in the same manner as in the reaction step [I] to easily give a compound represented by the general formula ( The optically active compound represented by 1) can be obtained.

(Manufacture of Element) For manufacturing an element using the liquid crystal compound of the present invention, a conventional element manufacturing technique using a ferroelectric liquid crystal can be applied. That is, it can be obtained by injecting a liquid crystal compound into a structure in which two transparent substrates each having a transparent electrode and having a surface subjected to an alignment treatment are bonded together with a spacer interposed therebetween. As the material of the alignment film, polyvinyl alcohol, polyimide, SiO, SiO ₂ or the like can be used. As spacers, silica beads,
Alumina beads, glass fibers, polymer films and the like can be used.

[0019]

INDUSTRIAL APPLICABILITY The optically active compound of the present invention has a molecular structure different from that of a conventionally known antiferroelectric liquid crystal material and has three stable molecular alignment states excellent in high-speed response. Liquid crystalline material, it has the ability to solve the problems of conventional surface-stabilized ferroelectric liquid crystal devices. This characteristic gives the element using this optically active compound the possibility of being used more than conventional products.

[0020]

EXAMPLES The present invention will be described in more detail below with reference to examples. In addition, the measurement of the phase transition temperature and the identification of the phase in the examples were carried out by observing the electric field response of the device manufactured in DSC and the example 5 with a polarization microscope.

(Example 1) (R) -4'-nonyloxybiphenyl-4-carboxylic acid
Acid-2-fluoro-4- (1-trifluoromethyl-5)
-Methoxypentyloxycarbonyl) phenyl ester
Le (Compound No.2) [I] (R)-3-fluoro -4-benzyloxy-benzoic acid-1-trifluoromethyl-5-methoxy pentyl ester 3-fluoro-4-benzyloxy benzoic acid 1. 20 g
(4.87 mmol), 0.75 g (4.03 m) of (R) -1-trifluoromethyl-5-methoxypentanol
mol), 0.30 g of N, N-dimethylaminopyridine
After mixing (2.45 mmol) and 30 ml of methylene chloride and stirring at room temperature, 1.24 g (6.01 mmol) of dicyclohexylcarbodiimide was added and reacted at room temperature for 2 hours.

After completion of the reaction, the precipitated solid matter was separated by filtration, washed with water, washed with a 5% acetic acid aqueous solution, washed with water, and then dried over anhydrous magnesium sulfate. The desiccant was filtered off and the ether was distilled off to obtain a crude target product. By purifying this by silica gel column chromatography,
1.60 g (3.70 mmol) of the target (R) -3-fluoro-4-benzyloxybenzoic acid-1-trifluoromethyl-5-methoxypentyl ester was obtained.

[II] Preparation of (R) -3-fluoro-4-hydroxybenzoic acid-1-trifluoromethyl-5-methoxypentyl ester (R) -3-fluoro-4-benzyloxybenzoic acid-
After dissolving 1.50 g (3.47 mmol) of 1-trifluoromethyl-5-methoxypentyl ester in 30 ml of acetic acid, 350 m of 5% palladium carbon under a hydrogen atmosphere.
g, and reacted at room temperature for 2 hours. After completion of the reaction, palladium carbon was filtered off and acetic acid was distilled off to obtain a crude target product.
By purifying this by silica gel column chromatography, the desired (R) -3-fluoro-
4-Hydroxybenzoic acid-1-trifluoromethyl-5
-Methoxypentyl ester 1.05 g (3.06 mm
ol) was obtained.

[III] Target compound (Compound No. 2)
Production of (R) -3-fluoro-4-hydroxybenzoic acid-1-trifluoromethyl-5-methoxypentyl ester obtained in the above [II] 152 mg (0.45 mmo)
l) 184 mg (0.54 mmol) of 4'-nonyloxybiphenyl-4-carboxylic acid, and 33 mg (0.27 mmo) of N, N-dimethyl-4-aminopyridine.
10 ml of methylene chloride was added to (1) and stirred at room temperature, and then 140 mg of dicyclohexylcarbodiimide (0.
68 mmol) was added and reacted at room temperature for 2 hours.

After completion of the reaction, the precipitated solid matter was separated by filtration, washed with water, washed with 5% acetic acid aqueous solution, washed with water, and then dried over anhydrous magnesium sulfate. The desiccant was filtered off and methylene chloride was distilled off to obtain a crude target product. This product is purified by silica gel column chromatography to give the desired (R) -4′-nonyloxybiphenyl-4.
234 mg (0.35 mmol) of -carboxylic acid-2-fluoro-4- (1-trifluoromethyl-5-methoxypentyloxycarbonyl) phenyl ester was obtained.

¹ H-NMR spectrum (ppm) 0.88 (t, 3H), 1.23-1.68 (m, 16H), 1.75-1.88 (m, 2H),
1.88-1.98 (m, 2H), 3.30 (s, 3H), 3.39 (t, 2H), 4.00 (t, 2
H), 5.53−5.62 (m, 1H), 7.00 (d, 2H), 7.44 (t, 1H), 7.60
(d, 2H), 7.74 (d, 2H), 7.90-8.01 (m, 1H), 8.25 (d, 2H) IR spectrum (cm ^-1 ) 2900, 2830, 1740, 1600, 1500, 1420, 1270, 1250 , 11
80, 1110, 1050, 820,760, 680 Phase transition temperature (℃)

[0027]

[Chemical 5]

However, Cry is a crystal phase, SmC _A ^* is a chiral smectic C _A phase, and SmA is a smectic A phase.
Phase, Iso represents an isotropic liquid phase. The value in the upper row is 5 ° C / min when the temperature in the upper row is 5 ° C / min.
Represents the phase transition temperature when the temperature is lowered at.

(Example 2) (R) -4'-decyloxybiphenyl-4-carboxylic acid-2-fluoro-4- (1-trifluoromethyl-5)
-Methoxypentyloxycarbonyl) phenyl ester (Compound No. 3) (R) -3-fluoro-obtained in [II] of Example 1.
4-Hydroxybenzoic acid-1-trifluoromethyl-5
-Methoxypentyl ester 150 mg (0.45 mm
ol), 190 mg (0.54 mmol) of 4'-decyloxybiphenyl-4-carboxylic acid, and 33 mg (0.27 mmo) of N, N-dimethyl-4-aminopyridine.
10 ml of methylene chloride was added to (1) and stirred at room temperature, and then 140 mg of dicyclohexylcarbodiimide (0.
68 mmol) was added, and the mixture was reacted at room temperature for 4 hours.

After completion of the reaction, the precipitated solid matter was filtered off, washed with water, washed with a 5% acetic acid aqueous solution, washed with water, and then dried over anhydrous magnesium sulfate. The desiccant was filtered off and methylene chloride was distilled off to obtain a crude target product. By purifying this by silica gel column chromatography, the target (R) -4′-decyloxybiphenyl-4 was obtained.
-Carboxylic acid-2-fluoro-4- (1-trifluoromethyl-5-methoxypentyloxycarbonyl) phenyl ester 250 mg (0.37 mmol) was obtained.

¹ H-NMR spectrum (ppm) 0.89 (t, 3H), 1.21-1.68 (m, 18H), 1.74-1.87 (m, 2H),
1.88-1.97 (m, 2H), 3.31 (s, 3H), 3.40 (t, 2H), 4.01 (t, 2
H), 5.51-5.60 (m, 1H), 7.02 (d, 2H), 7.42 (t, 1H), 7.62
(d, 2H), 7.75 (d, 2H), 7.88−8.00 (m, 1H), 8.26 (d, 2H) IR spectrum (cm ⁻¹ ) 2920, 2850, 1740, 1610, 1510, 1420, 1260, 1250 , 11
95, 1110, 1060, 820,770, 680 Phase transition temperature (℃)

[0032]

[Chemical 6]

However, Cry is a crystalline phase, SmC _A ^* is a chiral smectic C _A phase, and SmA is a smectic A phase.
Phase, Iso represents an isotropic liquid phase. The value in the upper row is 5 ° C / min when the temperature in the upper row is 5 ° C / min.
Represents the phase transition temperature when the temperature is lowered at.

(Example 3) (R) -4'-undecyloxybiphenyl-4-carboxylic acid-2-fluoro-4- (1-trifluoromethyl-5-methoxypentyloxycarbonyl) phenyl ester (Compound No. .4) (R) -3-fluoro-obtained in [II] of Example 1
4-Hydroxybenzoic acid-1-trifluoromethyl-5
-Methoxypentyl ester 150 mg (0.45 mm
ol), 4'-undecyloxybiphenyl-4-carboxylic acid 200 mg (0.54 mmol), and N, N
-Dimethyl-4-aminopyridine 33 mg (0.27 m
(mol) and methylene chloride (10 ml) were added and the mixture was stirred at room temperature, then dicyclohexylcarbodiimide (140 mg)
(0.68 mmol) was added, and the mixture was reacted at room temperature for 3 hours.

After completion of the reaction, the precipitated solid matter was separated by filtration, washed with water, washed with a 5% acetic acid aqueous solution, washed with water, and then dried over anhydrous magnesium sulfate. The desiccant was filtered off and methylene chloride was distilled off to obtain a crude target product. By purifying this by silica gel column chromatography, the desired (R) -4'-undecyloxybiphenyl-4-carboxylic acid-2-fluoro-4- (1-trifluoromethyl-5-methoxypentyl) was obtained. Oxycarbonyl)
260 mg (0.38 mmol) of phenyl ester was obtained.

¹ H-NMR spectrum (ppm) 0.89 (t, 3H), 1.22-1.69 (m, 20H), 1.73-1.86 (m, 2H),
1.89−2.01 (m, 2H), 3.32 (s, 3H), 3.39 (t, 2H), 4.00 (t, 2
H), 5.54-5.62 (m, 1H), 7.01 (d, 2H), 7.41 (t, 1H), 7.64
(d, 2H), 7.74 (d, 2H), 7.88-8.01 (m, 1H), 8.25 (d, 2H) IR spectrum (cm ^-1 ) 2910, 2840, 1750, 1610, 1505, 1410, 1255, 1245 , 11
90, 1105, 1055, 830,770, 690 Phase transition temperature (℃)

[0037]

[Chemical 7]

However, Cry is a crystalline phase, SmC _A ^* is a chiral smectic C _A phase, and SmA is a smectic A phase.
Phase, Iso represents an isotropic liquid phase. The value in the upper row is 5 ° C / min when the temperature in the upper row is 5 ° C / min.
Represents the phase transition temperature when the temperature is lowered at.

(Example 4) (R) -4'-decylbiphenyl-4-carboxylic acid-2
-Fluoro-4- (1-trifluoromethyl-5-methoxypentyloxycarbonyl) phenyl ester (Compound No. 29) (R) -3-fluoro-obtained in [II] of Example 1.
4-Hydroxybenzoic acid-1-trifluoromethyl-5
-Methoxypentyl ester 150 mg (0.45 mm
ol), 4'-decylbiphenyl-4-carboxylic acid 18
10 mg of methylene chloride was added to 0 mg (0.54 mmol) and 33 mg (0.27 mmol) of N, N-dimethyl-4-aminopyridine, and after stirring at room temperature, 140 mg (0.68 m of dicyclohexylcarbodiimide).
mol) was added, and the mixture was reacted at room temperature for 2 hours.

After the completion of the reaction, the precipitated solid matter was filtered off, washed with water, washed with a 5% acetic acid aqueous solution, washed with water, and then dried over anhydrous magnesium sulfate. The desiccant was filtered off and methylene chloride was distilled off to obtain a crude target product. By purifying this by silica gel column chromatography, the target (R) -4′-decyloxybiphenyl-4 was obtained.
-240 mg (0.36 mmol) of carboxylic acid-2-fluoro-4- (1-trifluoromethyl-5-methoxypentyloxycarbonyl) phenyl ester was obtained.

¹ H-NMR spectrum (ppm) 0.88 (t, 3H), 1.26-1.44 (m, 18H), 1.61-1.73 (m, 2H),
1.89−2.00 (m, 2H), 2.61−2.70 (m, 2H), 3.31 (s, 3H), 3.3
9 (t, 2H), 5.51-5.61 (m, 1H), 7.34 (m, 2H), 7.44 (t, 1H),
7.59 (d, 2H), 7.75 (d, 2H), 7.91−8.00 (m, 2H), 8.26 (d, 2
H) IR spectrum (cm ^-1 ) 2900, 2850, 1740, 1610, 1500, 1260, 1170, 1050, 93
0,750 Phase transition temperature (℃)

[0042]

[Chemical 8]

However, Cry is a crystalline phase, SmC _A ^* is a chiral smectic C _A phase, and SmA is a smectic A phase.
Phase, Iso represents an isotropic liquid phase. The value in the upper row is 5 ° C / min when the temperature in the upper row is 5 ° C / min.
Represents the phase transition temperature when the temperature is lowered at.

(Embodiment 5) Two glass substrates with transparent electrodes were spin-coated with polyimide as an alignment film and subjected to rubbing treatment, so that the rubbing directions thereof were parallel to each other at 1.5 μm. The cells were assembled by laminating at the gap intervals of. The compound obtained in Example 2 was poured into it in an isotropic liquid state and then gradually cooled to a liquid crystal state. This was sandwiched between a polarizer whose transmission axes were orthogonal to each other and an analyzer, and the angle of the cell with respect to the polarizer was adjusted so that the amount of transmitted light was minimized when the applied voltage was 0V. When the change in the amount of transmitted light with respect to the change in applied voltage was measured at 48 ° C. for the element prepared by the above procedure, it was confirmed that this element had three stable molecular arrangement states with excellent high-speed response, and It has become clear that the above-mentioned problems of the surface-stabilized ferroelectric liquid crystal device can be solved. These are shown in FIG. The amount of transmitted light was 100% when the transmission axis of the analyzer was rotated to match the transmission axis of the polarizer.

This is 10 V or − at 48 ° C.
It is shown that by applying a bias voltage of 10 V, it is possible to drive by utilizing the memory property between one dark state and each of two bright states. At 48 ° C., the response time from the dark state to the bright state when the applied voltage is instantaneously changed from 0 V to 30 V is 8
The response time from the bright state to the dark state was 700 μs when the applied voltage was instantaneously changed from 30 V to 0 V for 700 μs, and the high-speed response of the switching between the states to the applied voltage change was recognized. Furthermore, this device has few defects due to the chevron structure, has a good molecular orientation, and
At 8 ° C., the contrast ratio between the dark state and the bright state was 1:35. In addition, when the compound in this device was crystallized to disturb the alignment state, it was returned to the liquid crystal state again and a voltage was applied for switching, and defects due to crystallization disappeared, and recovery of the alignment state was observed. It was

[Brief description of drawings]

FIG. 1 is a graph showing changes in the amount of transmitted light with respect to an applied voltage of the display element prepared in Example 5.

Front page continued (72) Inventor Noriko Iimura 8-3-1 Chuo, Ami-cho, Inashiki-gun, Ibaraki Mitsubishi Petrochemical Co., Ltd. Tsukuba Research Institute

Claims (2)

[Claims] 1. An optically active compound represented by the general formula (1). [Chemical 1] (In the formula, R ¹ is an alkyl group or an alkoxyl group having 1 to 20 carbon atoms, R ² is an alkyl group having 1 to 12 carbon atoms, and n is an integer of 4 to 12) 2. A display device using an optically active compound represented by the general formula (1). [Chemical 2] (In the formula, R ¹ is an alkyl group or an alkoxyl group having 1 to 20 carbon atoms, R ² is an alkyl group having 1 to 12 carbon atoms, and n is an integer of 4 to 12)