JPS62169883A - Liquid crystal element - Google Patents

Abstract

PURPOSE:To improve the initial orientation of liquid crystal molecules thereby improving the display and drive, by forming a cell structure in which a liquid crystal material containing a liquid crystal compound having optically active groups is enclosed in between a pair of substrates and providing a specified orienting effect. CONSTITUTION:A liquid crystal element having a cell structure in which either a liquid crystal material mentioned below comprising a liquid crystal compound having optically active groups, represented by formula I, or a liquid crystal composition containing this compound is enclosed in between a pair of substrates mentioned below. The aforementioned liquid crystal material has a smectic phase formed by phase transition from the higher temperature side and also has an effect of preferentially unidirectionally orienting the axis of molecules which comes in contact at the interface with the surface of at least one of the pair of the substrates aforementioned. In formula I, R is 1-16C alkyl; C* is an asymmetric carbon atom; R<1> is 4-16C alkyl or alkoxy; formulas II-IV each represents phenylene, cyclohexylene or pyrimidinylene; p is 0 or 1; q is 1 or 2 when p=1;, l, m, and n are each 0 or an integer that satisfies the relation l+m+n>=2.

Description

[Detailed description of the invention]

1. The present invention relates to a liquid crystal element applied to a liquid crystal display element, a liquid crystal-optical shutter array, etc., and more specifically, a liquid crystal element with improved display and driving characteristics by improving the initial alignment state of liquid crystal molecules. Regarding. ■11th week Conventional liquid crystal elements include 1, for example, M. Shaft (M, 5chadt) and W, Helfrich (W, He1frich), "Apply 1-, Fizuix, Letters °' Volume 18, No. 4 ("Appli
ed Physics and etters”,
Vol, I8. No. 4) (1971,
2, 15), P, 127-128 “Voltage-dependent optical behavior of twisted nematic liquid crystals” (“Voltage-
Dapendent Optical Activity
or a Twisted Nematic Liq
A device using a TN (twisted nematic) liquid crystal described in Uid Crysta1'°) is known. However, this TN liquid crystal has a problem in that crosstalk occurs during time-division driving using a matrix electrode structure with high pixel density, so the number of pixels is limited. Furthermore, a display element is known in which a switching element using a thin film transistor is connected to each pixel, and each pixel is switched. However, the process of forming the thin film transistor on the substrate is extremely complicated, and the display element has a large area. There are some problems that make it difficult to create. To improve the drawbacks of conventional liquid crystal devices, the use of bistable liquid crystal devices has been proposed by Clark (C
1ark) and Lagerwal
l) (Japanese Unexamined Patent Publication No. 56-10721)
Publication No. 8, US patent! 84387924 specification etc.),
Bistable liquid crystals are generally chiral metatic C phase (SmC") or H phase (SmH").
A ferroelectric liquid crystal having the following characteristics is used. This liquid crystal has a bistable state consisting of a first optically stable state and a second optically stable state with respect to an electric field. The first optically stable state I for the electric field vector of
The liquid crystal is oriented to E, and the second electric field vector is aligned to E.
The liquid crystal is aligned in an optically stable state. Furthermore, this type of liquid crystal has the property of very quickly taking one of the above two stable states in response to an applied electric field, and maintaining that state when no electric field is applied. By utilizing these properties, significant improvements can be made to many of the problems of conventional TNfi devices mentioned above. This point will be explained in more detail below in connection with the present invention. However, in order for an optical modulation element using this bistable liquid crystal to exhibit predetermined driving characteristics, the liquid crystal placed between a pair of parallel substrates must be It is necessary that the molecules be in such a state that conversion between stable states can occur effectively. For example, for ferroelectric liquid crystals with SmC'' or SmH'' phases. SmC! Or, it is necessary to form a compensation sphere (monodomain) in which the liquid crystal molecular phase having the "SmH" phase is perpendicular to the substrate surface, and the liquid crystal molecular axes are arranged almost parallel to the substrate surface. In optical modulation elements using stable liquid crystals, the actual situation is that sufficient characteristics cannot be obtained because the alignment state of the liquid crystals having such a monodomain structure is not necessarily formed satisfactorily. For example, according to C1ark et al., methods of applying a magnetic field, methods of applying a shear force, methods of applying a magnetic field, methods of applying a shear force, methods of applying a parallel ridge between the substrates at small intervals, etc.
) have been proposed. However, none of these methods necessarily gave satisfactory results. For example, the method of applying a magnetic field is
There are disadvantages in that it requires large-scale equipment and is incompatible with thin-layer cells with good operating characteristics.Also, the method of applying shear force is incompatible with the method of injecting liquid crystal after creating the cell. There are some difficulties. Further, the method of arranging parallel edges within a cell cannot provide a stable alignment effect by itself. In view of the above-mentioned circumstances, an object of the present invention is to develop a ferroelectric material that has potential suitability as a display element having high-speed response, high-density pixels, and a large area, or an optical shutter having a high shutter speed. The object of the present invention is to provide a ferroelectric liquid crystal element that can fully exhibit its characteristics by improving monodomain formation or initial orientation, which has been a problem in the prior art. As a result of research in line with the above-mentioned purpose, the inventors have developed a method of sandwiching a liquid crystal or a composition containing the liquid crystal between substrates that have been subjected to an axial self-alignment treatment effect to form a smectic phase. Phases on the high temperature side, e.g. cholesteric phase (chiral nematic phase)
For example, when a phase transition from a nematic phase or an isotropic phase is caused by slow cooling, a monodomain in which liquid crystal molecules are aligned in one direction can be formed when forming SmA or a chiral smectic phase, resulting in ferroelectric properties. It has been discovered that a liquid crystal element can be obtained with a structure that allows for both operation of the element based on the bistability of the liquid crystal and monodomain property of the liquid crystal layer. The liquid crystal element of the present invention is based on the above-mentioned findings,
More specifically, it is a liquid crystal element having a cell structure in which a liquid crystal material made of an optically active liquid crystal compound represented by the following general formula (1) or a liquid crystal composition containing the compound is sealed between a pair of substrates, and the liquid crystal The liquid crystal material takes a smectic phase formed by a phase transition from the high temperature side, and has the effect of arranging the molecules in one direction with priority given to the molecular axis direction where the surfaces of at least one of the pair of substrates touch at the interface. It is characterized by the fact that General formula [Here, R represents an alkyl group having 1 to 16 carbon atoms, and C
g represents an asymmetric carbon atom, and R1 represents an alkyl group having 4 to 16 carbon atoms. is an alkoxy group, (), sha, (
are phenylene-BS, cyclohexylene, and p, respectively.
is 0 or 1, and when p=l, q is 1 or 2. Also, j, m, n are! It is O or a positive integer that satisfies the relationship +m+n≧2. )] Hereinafter, the present invention will be described in further detail with reference to the drawings as necessary. The liquid crystal compound (optically active alkanenitrile derivative) represented by the general formula (1) used in the liquid crystal element of the present invention can be used alone or in the form of a composition in combination with other liquid crystal compounds, for example. , chiral smectic C
Phase (SmC”), H phase (SmH”), I phase (SmI”)
, J phase (SmJ”), Ni phase (SmK”), G phase (Sm
It can be a ferroelectric chiral smectic liquid crystal material having a phase (SmF'') or an F phase (SmF''). The optically active alkane nitrile derivative represented by the above general formula (I) is preferably 2-hydroxyalkane nitrile or p-hydroxyalkane nitrile as shown in the specification of Japanese Patent Application No. 187718/1982, p-hydroxyammonyl, fragrant acid- It is synthesized from optically active intermediates such as (1-cyanomethyl)alkyl ester and p-hydroxybiphenylcarboxylic acid-(1-cyanomethyl)alkyl ester. For example, a liquid crystalline compound represented by general formula (I) can be obtained from these optically active intermediates by the following synthetic route. R' A, B m C, C00H SO (I2R''A, B, C, COCl (however,
R1, Sha, Go, No., p. Q.1. m and n are as defined above. )Table 1
Examples of alkannitrile derivatives obtained in this manner are shown below. It is also preferable to use the alkane nitrile derivative represented by the above general formula (I) as a composition in combination with other liquid crystalline compounds 6 For example, this alkane nitrile derivative represented by the following formulas (1) to (13) When combined with a ferroelectric liquid crystal such as ferroelectric liquid crystal, spontaneous polarization increases and response speed can be improved. In such a case, the flukanitrile derivative of the present invention represented by the general formula (, ■) should be used in a proportion of 0.1 to 99% by weight, particularly 1 to 90% by weight of the resulting liquid crystal composition. is preferred. Phenyl ester 42 43.5 58.5
82Cr7st, -111-ra SmC”
-5IaA -111-ri Ch, -11111 Iso. Phenyl ester 18\Si' 143.5 Phenyl ester Cryst, --→SmC'' --→ SaA --
La Eso. Phenyl ester 49.5 83 CrysL-m-→Sa+A--→Igo. Sf''/4B Phenyl ester Cryst, --→5aIc'-1→SmA-1→rso. -Methylbutylcinnamate (DOBAMBC)Hs -COOCHt CHCt Hs 4.4'-7 −
By blending methylbutyl) ester with a smectic liquid crystal which itself is not chiral, such as those shown by the following formulas 1) to 5), a composition usable as a ferroelectric liquid crystal can be obtained. In this case, the uninvented flukanitrile represented by general formula (I)? The A conductor is 0.1 to 99% of the obtained liquid crystal composition.
It is preferable to use it in a concentration of 1% to 90%. -” Cs H1? OmCOOLUOC* Hts(4
-nonyloxyphenyl)-4'-octyloxybiphenyl-4-carboxylateney 217'0,.哩二1. -4□SQ. Cryd, 5d 74℃ 0108210℃-pq, #N-@-QC,Q)Itt
4.4'-decyloxyazoxybenzene Crrst,
77”f13 Sec 120”c N
123' (Iso. Cs HIx04 Meiku 5)-QCs HI22-(4'
-hexyloxyphenyl) -5-(4-hexyloxyphenyl)pyrimidine C'1"t,
l HI7 + c, H1l1 2-(4"-octyloxyphenyl)-5-7ylpyrimidine Cryst, 33"C5rnC60"CS
mA? 5" (Iso. 4'-Pentyloxyphenyl-4-octyloxybenzoate Crest, 58°C Sml 64°C
5caA 6B℃ N 85℃ Iso. −1−−−ri −◆ −−−1−Cee〉Here, the symbols indicate the following phases, respectively. Crys': crystal phase, S+wA
: Smectic A phase. SmB: smectic B phase, Sml: smectic C phase. N: Nematic phase, Iso: Isotropic phase. Such a composition can obtain a large spontaneous polarization depending on the content of the uninvented alkane nitrile derivative. When constructing an element using these liquid crystal materials, in order to maintain the liquid crystal material at a temperature such as SmC'' phase or SmH' phase, the element may be placed in a copper block with a heater embedded, etc., depending on the need. Figure 1 schematically depicts an example of a cell for explaining the operation of a ferroelectric liquid crystal. 21a and 21b are
I n203.3n02 or I TO(
It is a substrate (glass plate) covered with a transparent electrode made of a thin film such as Indium-Tin 0w1de), between which a SmC" phase or SmH" phase liquid crystal is oriented so that the liquid crystal molecular layer 22 is perpendicular to the glass surface. It is enclosed. A thick line 23 represents a liquid crystal molecule, and this liquid crystal molecule 23 has a dipole moment (P) 24 in a direction perpendicular to the molecule. When a voltage higher than a certain threshold is applied between the electrodes on the substrates 21 and 21b, the liquid crystal molecules 23
The helical structure is unraveled, and the dipole moment (Pyo) 24
The alignment direction of the liquid crystal molecules 23 can be changed so that all of the liquid crystal molecules are oriented in the direction of the electric field. The liquid crystal molecules 23 have an elongated shape and exhibit refractive index anisotropy in the long axis direction and the short axis direction. Therefore, for example, if crossed Nicol polarizers are placed above and below the glass surface, the polarity of the applied voltage changes. It is easily understood that this results in a liquid crystal optical modulation element whose optical properties change. The liquid crystal cell preferably used in the optical modulation element of the present invention can have a sufficiently thin thickness (for example, 1O#L or less), and as the liquid crystal layer becomes thinner in this way,
As shown in Figure 2, even when no electric field is applied, the helical structure of the liquid crystal molecules unwinds, and its dipole moment Pa
Alternatively, Pb takes either an upward (34a) or downward (34b) state. When an electric field Ea or Eb of different polarity above a certain threshold value is applied to such a cell by the voltage applying means 31a and 31b as shown in FIG. 2, the dipole moment corresponds to the electric field vector of the electric field Ea or Eb. Then, the liquid crystal molecules change direction to upward direction 34a or downward direction 34b, and the liquid crystal molecules change direction accordingly. First stable state fQ 33 a or second stable state y
633b. As mentioned earlier, there are two advantages to using such ferroelectricity as an optical modulation element. The first is that the response speed is extremely fast, and the second is that the alignment of liquid crystal molecules has bistability. To further explain the second point, for example with reference to FIG. 2, the electric field Ea
When the voltage is applied, the liquid crystal molecules are aligned in a first stable state 33a, and this state remains stable even when the electric field is turned off. When an electric field Eb in the opposite direction is applied, the liquid crystal molecules are oriented to a second stable state 33b and change their orientation, but they remain in this state even after the electric field is turned off. Further, as long as the applied electric field Ea or Eb does not exceed a certain threshold value, the previous orientation state is maintained. In order to effectively realize such fast response speed and bistability, it is preferable that the cell be as thin as possible. The biggest problem in forming devices using liquid crystals with such ferroelectricity is, as mentioned earlier, that SmC
A layer having a "phase or SmH" was aligned perpendicularly to the substrate surface, and liquid crystal molecules were aligned approximately parallel to the substrate surface. It is difficult to form cells with high monodomain properties, and the main purpose of the present invention is to provide a solution to this problem. ff53 Figures (A) and (B) show an embodiment of a liquid crystal element according to the present invention. FIG. 3(A) is a plan view of the liquid crystal element of the present invention, and FIG. 3(B) is a cross-sectional view taken along the line AA. The cell structure 100 shown in FIG. 3 consists of a pair of substrates 101a and 1olb made of glass plates or plastic plates.
It has a cell structure in which the substrates are held at a predetermined distance by spacers 104 and bonded with adhesive 106 to seal the pair of substrates. Further, on the substrate 101a, an electrode group (for example, a scanning voltage application electrode group of a matrix electrode structure) consisting of a plurality of transparent electrodes 102a is formed in a predetermined pattern such as a strip pattern. On the board totb,
The transparent electrode mentioned above

A plurality of transparent electrodes 1 crossed with 02a
02b (for example, a signal voltage application electrode group in a matrix electrode structure) is formed. The substrate 10th provided with such a transparent electrode 102b includes, for example, silicon oxide, silicon dioxide, aluminum oxide, zirconia, magnesium fluoride, cerium oxide, cerium fluoride, silicon nitride, silicon carbide, and boronitride. Inorganic insulating materials such as polyvinyl alcohol,
Polyimide, polyamideimide, polyesterimide,
The alignment control film 105 may be formed using an organic insulating material such as polyparaxylerin, polyester, polycarbonate, polyvinyl acetal, polyvinyl chloride, polyamide, polystyrene, cellulose resin, melamine resin, urea resin, or acrylic resin. can. The orientation control film 105 is obtained by forming a film of an inorganic insulating material or an organic insulating material as described above, and then rubbing its surface in one direction with velvet, cloth, or paper. In another preferred embodiment of the present invention, the alignment control film 105 can be obtained by depositing an inorganic insulating material such as SiO or 5i02 on the substrate 101b by oblique vapor deposition. In the apparatus shown in FIG. 5, a Pel jar 501 is placed on an insulating substrate 503 having a suction port 505, and a vacuum pump (not shown) extending from the suction port 505 evacuates the Pel jar 501. . Crucible 507 made of tungsten or molybdenum is Pelger 50
Several grams of crystals 508 of S io , S io2 , MgF2A, etc. (1′) are placed in the crucible 507 . The crucible 507 has two lower arms 507a, 507b, which are connected to conductors 509, 510, respectively. A power supply 506 and a switch 504 are connected in series between external conductors 509, 510 of Pelger 501. Substrate 502 is positioned inside Pelger 501 directly above crucible 507 at an angle of zero to the vertical axis of Pelger 501 . When the switch 504 is opened, the Pel jar 501 is first evacuated to a vacuum of about 10-' mmHg pressure, and then the switch 504 is closed and the power supply 506 is turned on until the crucible 507 is incandescent at a suitable temperature and the crystal 508 is evaporated. Power is supplied by adjusting the The required current for a suitable temperature range (700-1000°C) is approximately 10100a@S. crystal 50
8 is then evaporated to form an upward molecular flow indicated by S in the figure, and the fluid S is incident on the substrate 502 at an angle of 0 with respect to the substrate 502, so that the substrate 502 is covered. Ya
be done. The angle 0 is the above-mentioned "incident angle", and the direction of the fluid S is the above-mentioned "oblique deposition direction". Determined by thickness calibration with respect to time. When a coating of appropriate thickness is formed, power from power source 506 is reduced, switch 504 is opened, and Pelger 50
First, the pressure is increased to atmospheric pressure and the substrate 502 is removed from the Pelger 501. In another specific example, after forming a film of the above-mentioned inorganic insulating material or organic insulating material on the surface of the substrate 101b made of glass or plastic, or on the substrate 101b, the surface of the film is etched by an oblique etching method. By doing so, an orientation control effect can be imparted to the surface. It is preferable that the orientation control i30 film 105 described in 111 also functions as an insulating film at the same time, and for this reason, the film thickness of this orientation control film 105 is generally in the range of 100 to 1 pL, preferably 500 to 5000 pL. Can be set to . This insulating film also has the advantage of being able to prevent the generation of current caused by trace amounts of impurities contained in the liquid crystal phase 103, and therefore does not deteriorate the liquid crystal compound even if the operation is repeated. do not have. Further, in the liquid crystal element of the present invention, a film similar to the above-mentioned alignment control film 105 can be provided on the other substrate lot. The liquid crystal layer 103 in the cell structure 100 shown in FIG.
SmC", Sm)!", SmI', SmJ", S
This chiral smectic phase liquid crystal layer 1O3, which can be ``mK'', ``SmG'', or ``SmF'', is composed of a gradual transition from a phase on the higher temperature side than the smectic phase, such as a cholesteric phase (chiral nematic phase), a nematic phase, and an isotropic phase. It is formed by undergoing a phase transition to SmA (smectic A phase) during the temperature decreasing process by cooling (1°C to 10°C/hour), and further undergoing a phase transition to the chiral smectic phase during the temperature decreasing process by slow cooling, or It can be formed by a phase transition from a cholesteric phase to a chiral smectile phase without going through SmA.One important feature of the present invention is that when the above-mentioned liquid crystal is used in the temperature decreasing process by slow cooling, , it is possible to efficiently form a monodomain smectic layer.The liquid crystal composition used in the present invention can form an equireal phase-cholesteric phase-3 mA chiral smectic phase or an equireal phase-3 mA chiral smectic phase in the temperature cooling process. Fig. 4 shows another specific example of the liquid crystal element of the present invention.The liquid crystal element shown in Fig. 4 has a pair of substrates 1.Ola
A plurality of spacer members 203 are arranged between and 101b. This spacer member 203 has 1, for example, a Sin, 5
i02. A12o3. Inorganic compounds such as ``r+o,'' or polyvinyl alcohol, polyimide, polyamideimide, polyesterimide, polyvaraxylylene, polyester, polycarbonate, polyvinyl acetal,
After forming a film of a resin such as polyvinyl 111ide, polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, yurya resin, acrylic resin, or photoresist resin by an appropriate method, a spacer member 203 is placed at a predetermined position. It can be obtained by etching it so that it is arranged. Such a cell structure 100 includes substrates 101a and 101b.
Polarizers 107 and 108 in a crossed Nicol state or a parallel Nicol state are respectively arranged on both sides of the electrodes 102a and 102b, and optical modulation occurs when a voltage is applied between the electrodes 102a and 102b. As described above, according to the present invention, a pair of liquid crystal materials each containing an optically active liquid crystal compound having a specific structure as a main component, at least one of which has been subjected to a uniaxial alignment treatment, are used. A ferroelectric liquid crystal element having excellent monodomain properties and excellent electric field response can be obtained by sealing between cut plates and forming a smectic layer by phase transition from the high temperature side. The present invention will be explained in more detail below with reference to Examples.几1北” Striped I with a pitch of 100gm and a width of 62.5gm
On a square glass substrate provided with a TO film as an electrode, the substrate was placed in the oblique evaporation apparatus shown in FIG. 5 with the side on which the ITO film serving as the electrode was placed facing downward, and then 5i02 was placed in a molybdenum crucible. The crystals were set. After that, the inside of the vapor deposition apparatus was made into a vacuum state of about lo' Torr, and 5i02 was obliquely vapor-deposited on the glass substrate by a predetermined method to form an obliquely vapor-deposited film of 800 people (electrode plate A).
. On the other hand, a polyimide forming solution (rPIQJ manufactured by Hitachi Chemical Co., Ltd., non-volatile content concentration 14.5 wt%) was applied using a spinner coater onto a glass substrate on which a similar striped ITO film was formed. Heating was performed at 120'C for 30 minutes to form a film of 800 people (electrode plate B). Next, a thermosetting epoxy adhesive was applied to the periphery of the A electrode plate except for the area that would become the injection hole by screen printing, and then the A? The Li electrode plate and the B electrode plate were stacked so that the striped pattern electrodes were perpendicular to each other, and the distance between the two electrode plates was maintained at 2 m using a polyimide spacer. Liquid crystal composition A having a monoisotropic phase and having the composition and phase transition temperature shown below was injected into the cell thus prepared through the injection port, and the injection port was sealed. When this cell was cooled slowly and maintained at 25°C, a pair of polarizers were placed in a crossed nicol state, and the cell was observed under a microscope. It was found that SmC1 was formed. Liquid crystal composition A: Spontaneous polarization PS = 48 nc/cm2 (25°C)
Prepare two square glass substrates with striped ITO electrodes with a pitch of 11007z and a width of 62.5 gm, and apply a polyimide forming solution (same as in Example 1) onto each substrate using a spinner. Apply with machine, 120
After heating at °C for 30 minutes, 200 °C for 60 minutes and 3 more
Heating was performed at 50° C. for 30 minutes to form 800 polyimide. When the polyimide films formed on these two substrates are stacked on each other, the rubbing directions are parallel to each other. Further, rubbing treatment with velvet was performed so that the striped ITO electrodes were perpendicular to each other. Next, a thermosetting epoxy adhesive was applied to the periphery of one of the substrates by screen printing except for the area that would become the injection port, and then the two substrates were placed so that the rubbing directions were parallel to each other as described above. The two substrates were placed together, and the distance between the two substrates was maintained at 2 m using a polyimide spacer. The above-mentioned liquid crystal composition A, which was in an equal phase, was injected into the thus prepared cell through the injection port, and the injection port was sealed. The temperature of this cell was lowered by slow cooling, and while the temperature was maintained, a pair of polarizers were placed in a crossed nicol state, and microscopic observation revealed that SmC' was a monodomain with a non-helical structure and no orientation defects. It was found that it was formed. A liquid crystal cell was prepared by replacing the liquid crystal composition A in Example 1 with the liquid crystal composition B shown below, and using the same steps except for the following. After enclosing liquid crystal composition B, a pair of polarizers were placed in a crossed nicol state, and microscopic observation revealed that it had a non-helical structure and a monodomain SmC'' with no alignment defects was formed.Liquid crystal. Ml composition B: % %

[Brief explanation of drawings]

FIG. 1 is a schematic perspective view of a liquid crystal element using a chiral stent liquid crystal, and FIG. 2 is a perspective view schematically showing the bistability of the liquid crystal element. FIG. 3(A) is a plan view of an example of the liquid crystal element of the present invention, and FIG. 3(B) is a plan view of an example of the liquid crystal element of the present invention.
It is a sectional view along a line. FIG. 4 is a sectional view showing another embodiment of the liquid crystal element of the present invention. FIG. 5 is a cross-sectional view schematically showing an oblique evaporation apparatus used in producing the liquid crystal element of the present invention. 101a, LO1bmms substrate, 102a, 102b***electrode. 103...Liquid crystal layer, 104.1 spacer, 105...Orientation control film, 106...Fist sealant. Layout Diagram 3 (B) 1st Prisoner 2: Diagram 31! I (A) Figure 3 (B) +02 (1105 Figure 4 Figure 5

Claims (1)

[Scope of Claims] A liquid crystal element having a cell structure in which a liquid crystal material consisting of a liquid crystal compound having an optically active group represented by the following general formula (I) or a liquid crystal composition containing the same is sealed between a pair of substrates. , and the liquid crystal material takes a smectic phase formed by a phase transition from the high temperature side, and is arranged in one direction with priority given to the molecular axis direction where the surface of at least one of the pair of substrates contacts at the interface. A liquid crystal element characterized by having an effect. General formula▲There are mathematical formulas, chemical formulas, tables, etc.▼(I) [Here, R represents an alkyl group having 1 to 16 carbon atoms,
^* indicates an asymmetric carbon atom. Also, R^1 has 4 to 1 carbon atoms.
6 alkyl or alkoxy groups, ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲There are mathematical formulas, chemical formulas, tables, etc.▼, ▲There are mathematical formulas, chemical formulas, tables, etc.▼ are respectively phenylene groups (▲Mathematical formulas, etc.) , chemical formulas, tables, etc. ▼)
, cyclohexylene group (▲Mathematical formula, chemical formula, table, etc. available▼), pyrimidinylene group (▲Mathematical formula, chemical formula, table, etc. available▼). p is 0 or 1, and when p=1, q is 1 or 2. Also, l, m, n are l+m+
It is 0 or a positive integer that satisfies the relationship n≧2. )]