JPS61208031A - Liquid crystal element - Google Patents

Abstract

PURPOSE:To improve a preliminary orientation by providing plural structural elements having stripe-like side walls on one of substrates, and by orientating the another one of the substrates in a parallel or a vertical direction against the extended direction of said structural elements, and by using a specific liquid crystal compd. CONSTITUTION:A plural structural elements 104 having the stripe-like side walls 106, 107 are arranged on one of the substrate 101 of a pair of electrode substrate 101, 110. The another substrate 110 is uniaxially oriented in a parallel or a vertical direction against the extended direction of the element 104, and the Sm phase of the liquid crystal compd. or the liquid crystal composition contg. therein shown by the formula I or II wherein R1 and R2 are each 1-18C alkyl or alkoxy group, (m) is 0-2, R* is an optical active alkyl group, and also phase-changed from the phase lying at a higher temperature side than that of the Sm phase, is formed on the another substrate. By constituting the titled element as mentioned above, the liquid crystal element having the structure compatible with both the operation of the element due to the phase stability of the ferroelectricity liquid crystal and the monodomain property of the liquid crystal 105 may be obtd., thereby enabling to remove a defect on the spacer edge, even if, in a memory state liable to generating the defect.

Description

Detailed Description of the Invention [Field of Industrial Application] 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, the present invention relates to a liquid crystal element applied to a liquid crystal display element, a liquid crystal-optical shutter array, etc. This invention relates to a liquid crystal element with improved driving characteristics.

[Conventional technology]

As a conventional liquid crystal element, for example, M-Shut (M,
5chadt) and W Helfrich (W, He
If rich) ``Applied Physics Leders''
Vol. 18, No. 4 (February 15, 1971), pp. 127-128, "Voltage Dependent Optical Activity - Oboor Fist Twisted Nematic Liquid Conflict Crystal"
(Voltage Dependent Optica
l Activity of a Twisted
Nematic LiquidCryst
Twisted nematic (t
A device using twisted nematic (twisted nematic) liquid crystal is known. 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 it is difficult to use a display element with 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 is proposed by Clark (C1
ark) and Lagauer (Lage rwa l l
) (Japanese Unexamined Patent Publication No. 56-107216, U.S. Patent No. 4,367,924, etc.), liquid crystals having bistability are generally chiral smectate C phase (SmC") or H phase. (SmH end).

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. Therefore, unlike the optical modulation element used in the TN type liquid crystal described above, for example, one The liquid crystal is aligned in a first optically stable state with respect to the electric field vector, and the liquid crystal is aligned in a second optically stable state with respect to the other electric field vector. In addition, this type of liquid crystal responds to an applied electric field and very quickly responds to the above-mentioned
It has the property of taking one of two stable states and maintaining that state when no electric field is applied. By utilizing such properties, considerable improvements can be obtained in many of the problems of the conventional TN type elements mentioned above. This point will be explained in more detail below in connection with the present invention. However, in order for this ferroelectric liquid crystal with bistability to exhibit predetermined driving characteristics, the liquid crystal placed between a pair of parallel substrates must be in the above two stable states, regardless of the applied state of the electric field. It is necessary that the molecules be arranged in such a state that conversion between them can occur effectively.

For example, for a ferroelectric liquid crystal having a SmC" or SmH" phase, the liquid crystal molecular layer having an SmC" or SmH" phase is perpendicular to the substrate surface, and therefore the liquid crystal molecular axes are aligned approximately parallel to the substrate surface. A monodomain (monodomain) needs to be formed. However, in conventional ferroelectric liquid crystal devices with bistability, the alignment state of the liquid crystal with such a domain structure was not always formed satisfactorily, so the actual situation was that sufficient characteristics could not be obtained. It is.

For example, according to C1ark et al., in order to provide such an orientation state, there are methods of applying a magnetic field, methods of applying a shear force, and methods of applying parallel ridges at small intervals between substrates.
) 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. Furthermore, the method of arranging parallel ridges within a cell cannot provide a stable alignment effect by itself.

[Problem that the invention seeks to solve]

In view of the above-mentioned circumstances, an object of the present invention is to provide a ferroelectric liquid crystal element 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 the monodomain formation property or initial orientation, which has been a problem in the past.

[Effect]

As a result of research with the above-mentioned purpose in mind, the inventors found that at least one surface of a pair of parallel substrates sandwiching a liquid crystal has a uniaxial alignment treatment effect by rubbing, etc., and a stripe disposed between a pair of substrates. In addition to using the effect of arranging structural members having shaped side walls, the following general formula (1)
Alternatively, the smectate phase of the liquid crystal compound shown in (2) or the liquid crystal composition containing the same, such as SmA (smectate A phase) or chiral smectate phase, is converted into a phase higher than the smectate phase, such as a cholesteric phase (chiral nematic phase). phase), nematic phase, and isotokyoshi phase by slow cooling, it is possible to form a smectic phase monodomain, which results in the operation of devices based on the bistability of ferroelectric liquid crystals and the liquid crystal layer. It has been found that a liquid crystal element having a structure that can achieve both monodomain properties can be obtained.

General formula (1) (wherein, m is Oll or 2, and R1 has 1 to 1 carbon atoms
8 represents an alkoxy group or an alkyl group, and R* represents an alkyl group having an optically active group. General formula (2) % formula %) (wherein, R2 is an alkoxy group or an alkyl group having 1 to 18 carbon atoms) (wherein R* represents an alkyl group having an optically active group) [Means for solving the problem] The liquid crystal element of the present invention is based on the above-mentioned findings,
More specifically, in a liquid crystal element in which a liquid crystal is sandwiched between a pair of parallel substrates, a first substrate of the pair of parallel substrates has a plurality of structures each having a side wall on the side that contacts the liquid crystal. The members are arranged in a stripe pattern, and the surface of the second substrate in contact with the liquid crystal is subjected to uniaxial alignment treatment in a direction substantially parallel or perpendicular to the extending direction of the plurality of structural members on the first substrate. and the general formula (
It is characterized in that the smectic phase of the liquid crystal compound shown in 1) or (2) or the liquid crystal composition containing the same is formed by phase transition by gradual cooling from a phase on the higher temperature side than the smectic phase.

〔Example〕

Hereinafter, the present invention will be described in further detail with reference to the drawings as necessary.

The liquid crystal used in the present invention has ferroelectricity, and specifically has chiral smectate C phase (SmC").
, H phase (SmH"), I phase (SmI"), J phase (Sm
A liquid crystal having a phase (SmK), a G phase (SmG"), or an F phase (SmF") can be used.

R1 in the general formula (1) and R2 in the formula (2) are linear or branched alkyl groups, particularly preferably an alkoxy group or an alkyl group having 4 to 10 carbon atoms, and R* in the formula is Among optically active alkyl groups, 2-methylbutyl group is particularly preferred.

The liquid crystal compound represented by the general formula (1) or (2) is
For example, it can be obtained by the synthesis method disclosed in JP-A-59-219251.

Representative examples of the liquid crystal compound represented by the general formula (1) are as follows.

(n) C7H150-■-coo-○-○-0-CH
2CHC2H5 zeroC3H170-Coo-O-Q-0-CH2CHC2H
Representative examples of the liquid crystal compound represented by general formula (2) are as follows.

These liquid crystals can be used alone or in combination of two or more, and can also be used with other ferroelectric liquid crystals, such as lfDOBAMBc.
, decyloxybenzylidene-y-amino-2-methylbutylcinnamate, HOBACPC, hexyloxybenzylidene-P'-7mi, /-2-chloropropylcinnamate, etc. to obtain good results. I can do it.

When constructing an element using these materials, in order to maintain the temperature state such that the liquid crystal compound becomes the S m C" phase or the Sm H" phase, the element may be placed in a copper block with a heater embedded, etc., as necessary. can be supported.

FIG. 1 schematically depicts an example of a cell for explaining the operation of a ferroelectric liquid crystal. 21a and 21b are In
203.5n02 or ITO (Indium-Ti
It is a substrate (glass plate) coated with a transparent electrode made of a thin film such as
SmC” phase or S
mH" phase liquid crystal is sealed. Line 23 shown by thick line
represents a liquid crystal molecule, and this liquid crystal molecule 23 has a dipole moment (on P) 24 in a direction perpendicular to the molecule.

When a voltage equal to or higher than a certain threshold is applied between the electrodes on the substrates 21a and 21b, the helical structure of the liquid crystal molecules 23 is unraveled, and the liquid crystal molecules 23 are aligned in the direction such that the dipole moment (P) 24 is all directed in the direction of the electric field. can be changed. The liquid crystal molecule 23 has an elongated shape and exhibits refractive index anisotropy in its long axis direction and short axis direction. Therefore, for example, if crossed Nicol polarizers are placed above and below the glass surface, the polarity of voltage application can be changed. It is easily understood that the liquid crystal optical modulation element has optical characteristics that change depending on the amount of the liquid crystal.

The liquid crystal cell preferably used in the liquid crystal element of the present invention can have a sufficiently thin thickness (for example, 10 g or less). As the liquid crystal layer becomes thinner in this way, the helical structure of the liquid crystal molecules unwinds even in the absence of an applied electric field, as shown in Figure 2, and a non-helical structure is adopted, and its dipole moment (Pa or Pb) is The state is either upward (34a) or downward (34b). 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. and upward direction 34a or r direction 34b
The liquid crystal molecules are oriented in either the first stable state 33a or the second stable state 33b.

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. Also, the electric field E
As long as a does not exceed a certain threshold, each orientation state is maintained. Such fast response speed and
In order to effectively realize 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
It is difficult to form a highly monodomain cell in which a layer having a SmH phase or a SmH terminal phase is aligned perpendicular to the substrate surface and liquid crystal molecules are aligned approximately parallel to the substrate surface, and this It is the main objective of the present invention to provide a solution to this point.

FIGS. 3A to 3C show an embodiment of an uninvented liquid crystal element. FIG. 3(A) is a perspective view of the same embodiment, FIG. 3(g) is a side sectional view thereof, and FIG. 3(C) is a front sectional view thereof. However, in FIG. 3(A), the liquid crystal and polarizer are not shown.

83 (A) to (C), a plurality of electrodes 1 are placed on a substrate 101 made of a glass plate, a plastic plate, etc.
A group of electrodes (eg, constituting a group of scanning electrodes) consisting of 02 is formed in a predetermined pattern by etching or the like. Furthermore, a plurality of side walls 106 and 1 are arranged in a stripe shape in a positional relationship that is alternately and parallel to these electrodes 102.
A spacer member 104 having a diameter of 07 is formed.

Furthermore, an insulating film 103 is formed to cover the electrode 102 except for the area where the spacer member 104 is formed on the substrate 101.

The spacer member 104 is made of polyvinyl alcohol, for example.
Polyimide, polyamideimide, polyesterimide,
Polyparaxylylene, polyester, polycarbonate, polyvinyl acetal, polyvinyl oxide, polyvinyl acetate, polyamide, polystyrene, cellulose resin.

Resins such as melamine resin, urea resin, acrylic resin, photosensitive polyimide, photosensitive polyamide, cyclized rubber photoresist, phenol/borac photoresist, or electron beam photoresist (polymethyl methacrylate, epoxidized-1, 4-polybutashin, etc.).

The insulating film 103 has a function of preventing charge injection from the electrode 102 to the liquid crystal layer, and is made of, for example, silicon oxide, silicon dioxide, or aluminum oxide.

It can be obtained, for example, by forming a film on a base using a compound such as zirconia, magnesium fluoride, cerium oxide, cerium fluoride, silicon nitride, silicon carbide, or boron nitride. In addition, there are other materials such as polyvinyl alcohol, polyimide, polyamideimide,
It can also be formed as a coating film of resins such as polyesterimide, polyparaxylerin, polyester, polycarbonate, polyvinyl acetal, polyvinyl chloride, polyvinyl acetate, polyamide, polystyrene, cellulose resin, melamine resin, urea resin, and acrylic resin. can. The thickness of the insulating film 103 depends on the charge injection prevention ability of the material and the thickness of the liquid crystal layer, but is usually between 50 and 50 mm.
Preferably, the number is set in a range of 500 to 5000 people.

On the other hand, the thickness of the liquid crystal layer is determined by the height of the spacer member 104, and is usually 0.21 L, although it depends on the ease of alignment peculiar to the liquid crystal material and the response speed required for the device.
~200k, preferably 200k, 0.5u ~IJtc7) Set within R range. Further, the width of the spacer member 104 is usually 0.
．． It is set in the range of 5 g to 50 g, preferably 1 square to 2 ol. If the pitch (distance) of the spacer members 104 is too large, it will inhibit uniform alignment of liquid crystal molecules;
If it is too small, the effective area as a liquid crystal optical element will be reduced. For this reason 1 usually 10J1. The pitch is set in the range ˜2 mm, preferably between 50 and 700 lu.

These spacer members 104 are formed into predetermined patterns and dimensions by various printing methods such as screen printing, or more preferably by techniques such as photolithography and electron beam lithography.

The liquid crystal element of the present invention includes the substrate 101 processed as described above and another substrate 110 stacked in parallel, and a plurality of electrodes (for example, signal electrodes) 111 are provided on this substrate 110. An insulating film 112 is further formed on the electrode group. Multiple (signal) electrodes 11
1 and the other plurality of (scanning) electrodes 102 can be wired in a matrix structure. The insulating film 112 on the substrate 110 is similar to the above-mentioned insulating film 103, and the insulating film 112 covers the liquid crystal layer 10.
The film is formed of the same material as the insulating film 103 described above. According to the present invention, the plane 1 formed by the insulating film 112 of this substrate 101
13 is subjected to uniaxial orientation treatment, and the orientation direction is approximately parallel to the extending direction of the spacer member 104 on the substrate 101 (that is, the angle formed between these two directions is θ).
Preferably O°≦θ<15@) or orthogonal (preferably 80″<θ<100″). At this time, a liquid crystal cell in which the angle θ formed by these two directions is orthogonal has a greater tendency to cause alignment defects than a liquid crystal cell in which the angle θ is parallel. According to research by the present inventors, when this process is applied, a liquid crystal cell with an angle θ parallel to the other can form monodomains with no alignment defects than a liquid crystal cell with an angle θ perpendicular to each other. If such a parallel or orthogonal relationship is not satisfied, the alignment of liquid crystal molecules at the edge portion of the spacer may be disturbed, or switching between bistable states may not be performed properly in a cell having a memory function. However, as can be seen from the range expression of θ above, 1
A deviation of up to about 5° is not a problem in practical use. Such uniaxial alignment treatment can be carried out by rubbing the insulating film 112 with velvet, cloth, or paper, as is well known for TN type liquid crystal cells, or by rubbing the insulating film 112 with velvet, cloth, or paper. Alternatively, this can be achieved by oblique vapor deposition of the insulating film 112.

Note that the above-described uniaxial alignment treatment basically does not need to be performed on the substrate 101, but it can be performed on the substrate 101 as well.
After a uniaxial orientation treatment substantially parallel to or perpendicular to the extension direction of 4, the insulation H'J 103 is formed by vapor deposition, or after the formation of the insulating film 103, a uniaxial orientation treatment is performed,
Thereafter, by selectively removing the effect of the thickness treatment on the surface 108 formed by the insulating film 103, the side wall 1 of the spacer member 104 is
It is desirable to selectively impart an alignment treatment effect to 06 and 107 in order to increase the response speed of the obtained liquid crystal element.

The liquid crystal element of the present invention includes a pair of parallel substrates 101 and 110.
A pair of polarizing means (polarizer 114 and analyzer 115) sandwiching the substrates 101 and 110 can be used. As the polarizer 114 and the analyzer 115, ordinary polarizing plates, polarizing films, or polarizing beam splitters can be used. In this case, the polarizing means can be arranged in a crossed Nicols state or a parallel Nicols state. be.

In the liquid crystal element of the present invention, a pair of parallel substrates are fixed so as to satisfy the mutual relationship between the extension direction of the spacer member and the uniaxial alignment treatment direction, and their peripheries are sealed with an epoxy adhesive or low melting point glass. After that, a ferroelectric liquid crystal is sealed and heated to an isotropic phase.
By slowly cooling while precisely controlling the temperature,
Obtainable.

2, the liquid crystal element of the present invention was explained based on a preferred embodiment thereof. However, it will be readily understood that various modifications may be made to the above embodiments within the scope of the present invention. For example, the member described as the spacer member 104 in the above example can also function as a spacer member by contacting both of the pair of parallel substrates, if it has a side wall to exert the necessary wall effect on the liquid crystal. You don't have to.

However, as can be seen from the above example, the spacer member is an example of a preferable structural member, and it is also possible to use a modified stripe-shaped spacer in which the spacer member 104 is arranged in a dot shape along a straight line. Further, the electrodes are not limited to the above-described simple striped matrix electrodes, but may be formed in other shapes, for example, electrode wiring having a 7-segment structure.

Hereinafter, a specific manufacturing example of the liquid crystal of the present invention will be explained.

Example 1 Pair (7) ITO (Indi un-Tin-
A polyimide film having a thickness of approximately 1,500 layers was formed on one side of the substrate on which a striped pattern electrode was formed, and rubbed in one direction. A polyimide film with a thickness of 2gm was formed on the other substrate, and a width of 20gm was formed at a pitch of 200gm by photoetching.
A striped spacer was formed.

As the polyimide, 5P-510 manufactured by Toshisha Co., Ltd. was used, and its N-methylpyrrolidone solution was applied by dipping or spinner coating to form a polyimide film.

Etching was performed using a mixture of hydrazine and NaOH = 1:1 as the etching solution, and heating it to 30°C.
The substrate on which the polyimide film was formed was immersed for 3 minutes to perform etching.

A pair of electrode substrates created using the above process.

A liquid crystal cell (cell thickness: 2 gm) was constructed by making the direction of the striped spacer and the rubbing direction substantially parallel to each other.

After injecting the following composition A of the Tokichi phase into this liquid crystal cell,
The temperature of the cell was slowly cooled at a rate of 5°C/hour, and SmC)k
created a liquid crystal cell. When this S m C* liquid crystal cell was observed with a polarizing microscope, it was found that a monodomain with a non-helical structure without any alignment defects was formed.

Beni JLJ Kikomi liquid crystal compound (11) 30 parts by weight/l
(12) 30 parts by weight tt
(7) 20 parts by weight // (g)
20 parts by weight Examples 2 to 3 In place of composition A used in Example 1, the following composition B was used.
(Example 2) and the liquid crystal compound (3) alone (Example 3), liquid crystal cells were created in exactly the same manner as in Example 1, and each S rri C)k liquid crystal cell was When observed under a polarizing microscope, the non-helical monodomain format with no orientation defects was confirmed in all cases.

1i77 liquid crystal compound (11) 20 parts by weight/
/ (+2) 20 parts by weight lf
(6) 10 parts by weight l/(7) 10
Parts by weight // (8) 10 parts by weight //
(9) 10 parts by weight Example 4 A polyimide film having a thickness of about 1500λ was formed on one of the substrates on which a pair of striped pattern electrodes made of ITO were formed, and rubbed in one direction. A polyimide film with a thickness of 2 pm was formed on the other substrate, and a width of 20 g was formed at a pitch of 200 JLm by photoetching.
m striped spacers were formed and rubbed in parallel to the direction of the striped spacers.

The polyimide is 5P-5i manufactured by Toshisha.

A polyimide film was formed by applying the N-methylpyrrolidone solution by dipping or spinner coating.

Etching was carried out by using a mixed solution of hydrazine:Na0H=1:l as an etching solution, heating it to 30 DEG C., and immersing the substrate on which the polyimide film was formed for 3 minutes.

A pair of electrode substrates prepared in the above steps were placed in a liquid crystal cell (cell thickness; composition A of the same-yoshi phase used in Example 1) by aligning the direction of the striped spacer and the rubbing direction almost parallel to each other. After injection, the temperature of the cell was increased to 5℃/
A liquid crystal cell of SmC water was prepared by slowly cooling the mixture at a rate of 100 hrs.

When this SmC water liquid crystal cell was observed with a polarizing microscope, it was found that a non-helical monodomain with no alignment defects was formed.

Example 5 In Example 1, a liquid crystal cell was constructed in the same manner as in Example 1, except that a pair of substrates were combined so that the direction of their rubbing treatment was perpendicular to the extending direction of the striped spacer.

When this liquid crystal cell was observed using a polarizing microscope, some alignment defects were observed near the edges of the striped spacers.

Example 6 A polyimide film with a thickness of about 1000λ was formed on one side of a substrate on which a pair of striped pattern electrodes made of ITO was formed, and a polyimide film was formed with a thickness of 27zm in one direction, and photoetching was performed. As a result, striped spacers having a width of 20 lumen with a pitch of 200 μm were formed.

The polyimide is 5P-5t manufactured by Toshisha.

A polyimide film was formed by applying the N-methylpyrrolidone solution by dipping or spinner coating.

Etching was carried out using a mixture of hydrazine and Na0H = 1:l as the etching solution, and heating it to 30°C.
Etching was performed by dipping the substrate on which the polyimide film was formed for 3 minutes.

A polyimide film similar to that described above was formed over the entire surface of the substrate on which the striped spacers were formed. However, the thickness of the polyimide film at this time was set to 1000 mm.Next, the surface of this polyimide film was subjected to a rubbing treatment in a direction parallel to the extending direction of the striped spacer.

Composition A under the cell phase was injected into the pair of electrode substrates created in the above steps so that their respective rubbing directions were parallel, and after slowly cooling to create an SmC wood liquid crystal cell with a non-helical structure, When observed using the same method as in Example 1,
Similar results were obtained.

It was found that this liquid crystal cell formed stable monodomains that did not cause alignment defects in SmC* even after being left for several days, compared to the liquid crystal cells used in other examples.

Furthermore, when this liquid crystal element was driven by applying a pulse signal of 1 m5e at 20 V, compared to the case of Example 1,
It was found that the contrast between the bright and dark states increases.

Comparative Example 1 When assembling the liquid crystal cell of Example 1, the pair of electrode substrates were stacked with the angle θ between the direction of the striped spacer and the rubbing direction set at 25°. , a non-helical structure S m C in the same manner as in Example 1
*Created a liquid crystal cell.

When this SmC* liquid crystal cell was observed in the same manner as in Example 1, black streaks caused by countless alignment defects were observed near the edges of the striped spacers, and these black streaks covered the electrode formation areas. It was found that even if two types of electrode signals having different polarities were applied between the pair of electrodes, the part where the black streaks were formed did not show any bistability.

Comparative Example 2 The same electrode substrate as that provided with the striped spacer and polyimide film used when creating the liquid crystal cell of Example 6 was prepared. Rubbing treatment was performed at an angle of 25°.

Next, one side of the electrode substrate that was the same as that used in Example 6 was prepared, and rubbed in one direction.

These two electrode substrates are stacked so that their rubbing directions are parallel, and then a cell is assembled.A SmC* liquid crystal cell with a non-helical structure is created in the same manner as in Example 1. Observation 1 of the liquid crystal cell using the same method as in Example 1
However, as in Comparative Example 1, an alignment defect fatal to a display device was observed.

Furthermore, although an electric signal was applied between the pair of electrodes in the same manner as described above, no bistability was observed.

〔Effect of the invention〕

As described above, according to the present invention, a structural member (
A uniaxial alignment treatment (e.g., rubbing) is performed on the other substrate, and the direction of the treatment is regulated to be approximately parallel or perpendicular to the structural member. 1) or (
By using the liquid crystal compound shown in 2) or a liquid crystal composition containing the same, defects at the spacer edge can be removed even in a memory state where defects are particularly likely to appear.

[Brief explanation of drawings]

FIG. 1 is a perspective view schematically showing a liquid crystal element using chiral smectic liquid crystal. FIG. 2 is a perspective view schematically showing the bistability of the liquid crystal element. Figure 3 (A)
3 is a perspective view of a liquid crystal element of the present invention, FIG. 3(B) is a side sectional view thereof, and FIG. 3(C) is a front sectional view thereof.

Claims (3)

[Claims] (1) In a liquid crystal element in which a liquid crystal is arranged between a pair of substrates, one of the pair of substrates has a plurality of structural members having sidewalls arranged in a stripe pattern, and At least one of the substrates is subjected to uniaxial alignment treatment in a direction substantially parallel or perpendicular to the extending direction of the plurality of structural members, and the following general formula (1) or (
2) A liquid crystal element characterized in that a smectic phase of the liquid crystal compound shown in item 2) or a liquid crystal composition containing the same is formed by phase transition from a phase on a higher temperature side than the smectic phase. General formula (1) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, m is 0, 1 or 2, and R1 has 1 to 1 carbon atoms.
8 represents an alkoxy group or an alkyl group, and R* represents an alkyl group having an optically active group. ) General formula (2) ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R_2 represents an alkoxy group or an alkyl group having 1 to 18 carbon atoms, and R* represents an alkyl group having an optically active group.) (2) The plurality of structural members having the side walls function as stripe-like spacer members between the pair of substrates and have a thickness suitable for imparting bistability to the ferroelectric liquid crystal. The liquid crystal element according to item 1. (3) The angle θ formed between the extension direction of the plurality of structural members having the side walls and the uniaxial orientation processing direction is 0°≦θ<15
2. The liquid crystal element according to claim 1, which satisfies the relationship: 0.degree. or 80.degree.<.theta.<100.degree.