JPH0611717A - Liquid crystal element - Google Patents

Abstract

(57) [Summary] [Object] To provide a liquid crystal element having an alignment film formed without using a rubbing method and exhibiting uniform and defect-free liquid crystal alignment. An electrode body 2a comprising a glass substrate 4, a transparent electrode 5a formed on the glass substrate 4 and an alignment film 6 formed on the surface of the transparent electrode 5a, a glass substrate 4, and the glass Another electrode body 2b consisting of an electrode 5b formed on a substrate 4 and an alignment film 6 formed on the surface of the electrode 5b, and a liquid crystal 3 arranged between the two electrode bodies 2a, 2b. A liquid crystal device 1 comprising the transparent electrode 5a and a monomolecular film having the alignment film 1 formed on the water surface.
And / or a Langmuir-Blodgett film obtained by laminating one or more layers on the surfaces of the glass substrates 4 and 4 on which the electrodes 5b are formed, and the dielectric anisotropy Δε of the liquid crystal 3 is It is more than 0 and 10 or less.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel liquid crystal device having a novel liquid crystal alignment film.

[0002]

2. Description of the Related Art In recent years, displays using liquid crystal elements have been widely used as display media for watches, televisions and the like.

FIG. 2 is a schematic sectional view of this liquid crystal element.
In the figure, 11 is a liquid crystal element, 12a and 12b are a pair of electrode bodies, and 13 is a liquid crystal. Electrode bodies 12a and 1
Reference numeral 2b includes a glass substrate 14 and a transparent electrode 15a or electrode 15b formed on the glass substrate 14. On the surface of the glass substrate 14 on which the transparent electrode 15a or the electrode 15b is formed, a surface-treated alignment film 1 is formed.
6 is formed.

The alignment film 16 in the liquid crystal element 11
Is a thin film formed by a physical method such as an oblique vapor deposition method of SiO or Au, a rubbing method or the like, or a physicochemical method such as a method of applying a polyimide resin and then performing a rubbing treatment.

However, the orientation film 16 formed by the oblique vapor deposition method is very advantageous for giving a predetermined pretilt angle to the liquid crystal, but on the other hand, since it is the vacuum vapor deposition method, it is 10 ^−5. A high vacuum of torr level is required,
Further, there is a drawback that mass productivity is poor, for example, the substrate must be tilted. Further, the alignment film 16 formed by the rubbing method has a defect that the productivity is likely to be deteriorated due to dust and static electricity generated during rubbing, and the quality is likely to be deteriorated. Therefore, there is a demand for an alignment film 16 formed without such a conventional technique.

Therefore, the inventors previously proposed a novel liquid crystal alignment film using a Langmuir-Blodgett film (hereinafter also referred to as an LB film) which does not require rubbing treatment (Japanese Patent Laid-Open No. 63-23131). issue). However, it has been found that depending on the liquid crystal material used, display defects such as reverse twist and reverse tilt may occur, limiting the practicality as a liquid crystal element.

[0007]

The present invention has been made in view of the problems of the prior art and the problems of the LB film previously proposed by the present inventors, and was formed without using the rubbing method. An object of the present invention is to provide a liquid crystal device having an alignment film and exhibiting a uniform liquid crystal alignment property with almost no defects.

[0008]

Means for Solving the Problems As a result of earnest studies on such problems, the inventors of the present invention have made the pretilt angle of the liquid crystal on the alignment film 5 to 20 by appropriately selecting the combination of the alignment film and the liquid crystal. 2 degrees, in which case
The present invention has been completed by finding that when a liquid crystal element is manufactured by adopting such a configuration, display defects such as reverse twist and reverse tilt do not occur.

That is, the liquid crystal element of the present invention comprises a glass substrate, a transparent electrode formed on the glass substrate, and an alignment film formed on the surface of the transparent electrode, and a glass substrate, A liquid crystal element comprising the other electrode body composed of an electrode formed on the glass substrate and an alignment film formed on the surface of the electrode, and a liquid crystal arranged between the two electrode bodies. A Langmuir-Blodgett film obtained by laminating one or more layers of a monomolecular film having the alignment film formed on a water surface on the surface of the glass substrate having the transparent electrode and / or the electrode formed thereon. Further, the dielectric anisotropy Δε of the liquid crystal is more than 0 and 10 or less.

In the liquid crystal display device of the present invention, the ratio of the splay elastic constant K1 and the bend elastic constant K3 of the liquid crystal,
It is preferable that K3 / K1 is 1.0 or more.

[0011]

The liquid crystal device of the present invention is obtained by laminating one or more layers of a monomolecular film having an alignment film formed on the water surface on the surface of a glass substrate having a transparent electrode and / or an electrode. Since it is a Langmuir-Blodgett film and the dielectric anisotropy Δε of the liquid crystal is more than 0 and 10 or less, the pretilt angle of the liquid crystal on the alignment film can be 5 to 20 degrees. Therefore, when a liquid crystal element is manufactured by adopting the configuration shown in FIG. 2, display defects such as reverse twist and reverse tilt do not occur.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described based on embodiments with reference to the accompanying drawings, but the present invention is not limited to such embodiments.

FIG. 1 is a schematic view of an embodiment of the liquid crystal element of the present invention. The liquid crystal element 1 of the present invention shown in FIG. 1 is similar to the liquid crystal element 11 shown in FIG. 2 in that a liquid crystal 3 is sealed between a pair of electrode bodies 2a and 2b. This pair of electrode bodies 2
One electrode body 2a of a and 2b comprises a glass substrate 4, a transparent electrode 5a formed on the glass substrate 4 and an alignment film 6 formed on the surface of the transparent electrode 5a, and the other electrode body 2a. 2b includes a glass substrate 4, an electrode 5b formed on the glass substrate 4, and an alignment film 6 formed on the electrode 5b.

Transparent electrode 5 used for one electrode body 2a
Examples of a include transparent conductive films such as ITO and SnO ₂ . Further, the electrode 5b used for the other electrode body 2b
Examples of the transparent conductive film include metals such as thin film transistors (TFTs), thin film diodes (TFDs), and A1.

The alignment film 6 is for uniformizing the molecular alignment of the liquid crystal, and a Langmuir-Blodgett film is used in the present invention. Further, as the liquid crystal 3, one having a dielectric anisotropy Δε of more than 0 and 10 or less is used. Among them, it is preferable to use one having a ratio of spray elastic constant K1 to bend elastic constant K3, K3 / K1, of 1.0 or more.

By appropriately selecting the combination of the alignment film 6 and the liquid crystal 3, it becomes possible to set the pretilt angle of the liquid crystal 3 on the alignment film 6 to 5 to 20 degrees. When the element 1 is manufactured, the liquid crystal element 1 free from display defects such as reverse twist and reverse tilt can be obtained. If the pretilt angle of the liquid crystal 3 is out of the above range, display defects such as reverse twist and reverse tilt will occur, which limits the practicality of the liquid crystal element 1. When the liquid crystal 3 that does not satisfy the above conditions is used, it becomes difficult to stably set the pretilt angle of the liquid crystal 3 to 5 to 20 degrees.

Further, the alignment film 6 has the general formula (I) (formula 3):

[0018]

[Chemical 3] A monomolecular film obtained by spreading an amphiphilic polymer substance having a repeating unit represented by on the surface of water, on the surface of the glass substrate 4 on which the transparent electrode 5a is formed, or on the glass on which the electrode 5b is formed. After laminating one or more layers, preferably about 1 to 11 layers, on the surface of the substrate, the amphipathic polymer substance is completely or partially represented by the general formula (II) (Chemical Formula 4):

[0019]

[Chemical 4] It is preferably a thin film obtained by performing a heat treatment so that a polyimide having a repeating unit represented by

The amphipathic polymer represented by the general formula (I) contains R ³ , R ⁴ , and
According to the progress of the cyclization reaction to a polyimide having a repeating unit represented by the general formula (II), which has a surface property determined by the properties of R ⁵ and R ⁶ and is represented by the general formula (II). The surface properties of the polyimide are dominant. Since the pretilt angle of the liquid crystal 3 on the thin film is determined by the surface property of the thin film, the pretilt angle of the liquid crystal 3 on the alignment film 6 can be controlled by the heat treatment temperature and the heat treatment time.

The number average molecular weight of the amphipathic molecular substance is
From the viewpoint of obtaining a substantially oriented thin film by the LB method described later,
2000-300000, preferably 2000-300
00.

R ¹ in the above general formula (I) is a tetravalent group having at least 2, preferably 5 to 20 carbon atoms, which may be an aromatic group or a cycloaliphatic group. May be a group in which an aromatic group and an aliphatic group are bonded, and further, these groups have 1 to 1 carbon atoms.
It may be an aliphatic group, a cycloaliphatic group or a group in which an aromatic group and an aliphatic group are bonded to each other, and these groups are a halogen atom, a nitro group, an amino group, a cyano group or methoxy. Group, a monovalent group such as an acetoxy group or the monovalent group is -O-, -COO-, -NHCO-, -CO-, -S.
It may be a group which is a derivative substituted with a group bonded to —, —CSS—, —NHCS—, —CS— and the like. Among these, a group characterized by benzenoid unsaturation having at least 6 carbon atoms is preferable from the viewpoint of heat resistance, chemical resistance, mechanical properties and the like.

The benzenoid unsaturation referred to in the present specification means
As used in the structure of a carbocyclic compound as shown in Formula 1, it is a term used in comparison with a quinoid structure, and refers to a structure having the same shape as a carbocycle contained in a common aromatic compound.

[0024]

[Equation 1]

There are no particular restrictions on the positions of the four bonds of R ¹ , that is, the positions of the bonds of the chemical formula 5, the chemical formula 6, the chemical formula 7, and the chemical formula 8 in the repeating unit represented by the general formula (I). In the case where two of each of the two bonds of the above exist in two adjacent carbon atoms constituting R ¹ , an amphipathic polymer having a repeating unit represented by the general formula (I) (amphoteric polyimide). It is preferable since a 5-membered ring is easily formed when a film or the like formed using a precursor) is polyimidized, and it is easily imidized.

[0026]

[Chemical 5]

[0027]

[Chemical 6]

[0028]

[Chemical 7]

[0029]

[Chemical 8]

Specific examples of R ¹ as described above include, for example, chemical formula 9, chemical formula 10, chemical formula 11, chemical formula 12, chemical formula 13, chemical formula 14,
Chemical formula 15, chemical formula 16, chemical formula 17, chemical formula 18, chemical formula 19, chemical formula 20, chemical formula 21, and the like.

[0031]

[Chemical 9]

[0032]

[Chemical 10]

[0033]

[Chemical 11]

[0034]

[Chemical 12]

[0035]

[Chemical 13]

[0036]

[Chemical 14]

[0037]

[Chemical 15]

[0038]

[Chemical 16]

[0039]

[Chemical 17]

[0040]

[Chemical 18]

[0041]

[Chemical 19]

[0042]

[Chemical 20]

[0043]

[Chemical 21]

R ² in the general formula (I) is a divalent group containing at least 2 carbon atoms, may be an aromatic group or an aliphatic group, and may be a cyclic group. It may be an aliphatic group, or may be a group in which an aromatic group and an aliphatic group are bonded, and further, these divalent groups are aliphatic groups having 1 to 30 carbon atoms, It may be a group in which a cycloaliphatic group or an aromatic group and an aliphatic group are bonded,
The group is a monovalent group such as a halogen atom, a nitro group, an amino group, a cyano group, a methoxy group and an acetoxy group, or the monovalent group is -O-, -COO-, -NHCO-, -C.
It may be a group substituted with a group bonded to O-, -S-, -CSS-, -NHCS-, -CS- and the like. Among these, groups characterized by benzenoid unsaturation having at least 6 carbon atoms are:
It is preferable in terms of heat resistance, chemical resistance, mechanical properties and the like.

Preferred specific examples of R ² as described above include, for example, Chemical formula 22, Chemical formula 23, Chemical formula 24, Chemical formula 25, Chemical formula 26
And so on. In the above chemical formula, R ⁷ is-(CH ₂ )
_m- (m is an integer from 1 to 3), Chemical formula 27, Chemical formula 28, -O-,
Over CO chromatography shows over S chromatography, chromatography SO ₂ over, over NR ⁸ over, of 29, of 30, of 31, the reduction 32. In the above chemical formula, R
⁸ and R ⁹ each represent an alkyl or aryl group having 1 to 30 carbon atoms.

[0046]

[Chemical formula 22]

[0047]

[Chemical formula 23]

[0048]

[Chemical formula 24]

[0049]

[Chemical 25]

[0050]

[Chemical formula 26]

[0051]

[Chemical 27]

[0052]

[Chemical 28]

[0053]

[Chemical 29]

[0054]

[Chemical 30]

[0055]

[Chemical 31]

[0056]

[Chemical 32]

R ³ , R ⁴ , R ⁵ and R ⁶ in the general formula (I) are each a halogen atom, a nitro group, an amino group, a cyano group, a methoxy group or an aliphatic group which may be substituted with an acetoxy group, or a cyclic group. 1 to 3 aliphatic or aromatic (which may be combined with each other) carbon atoms
It is 0, preferably 1 to 22 monovalent hydrocarbon groups or hydrogen atoms. In the general formula (I), R ³ , R ⁴ ,
R ⁵ and R ⁶ are both of the general formula (III)
3):

[0058]

[Chemical 33] (Wherein R ¹ and R ² are the same as above) are groups introduced to impart hydrophobicity to the polyamic acid unit and to obtain a stable condensed film. R ³ , R ⁴ and R ⁵ And R ⁶
At least one of them is optionally substituted with a halogen atom, a nitro group, an amino group, a cyano group, a methoxy group, an acetoxy group, an aliphatic group, a cycloaliphatic group, or an aromatic group (these groups are combined with each other. (May be) since it is a group having 12 to 30 carbon atoms, preferably 16 to 22 carbon atoms,
A stable condensed film is formed on the water surface and is accumulated on the substrate by the LB method.

Specific examples of the groups other than the hydrogen atom of R ³ , R ⁴ , R ⁵ and R ⁶ as described above include, for example, chemical formulas 34, 35, 36, 37, 38 and 39. Can be mentioned. Further, L in the above chemical formula is 12 to 30, and preferably 16 to 22.

[0060]

[Chemical 34]

[0061]

[Chemical 35]

[0062]

[Chemical 36]

[0063]

[Chemical 37]

[0064]

[Chemical 38]

[0065]

[Chemical Formula 39] Among these, it is particularly preferable to use the straight chain alkyl group represented by Chemical formula 40 in terms of performance and cost. In addition, since the hydrophobicity is dramatically improved by the fluorine atom as compared with the hydrogen atom, a fluorine atom is more preferable.

[0066]

[Chemical 40]

Specific examples of the amphipathic polymer having the repeating unit represented by the general formula (I) as described above include, for example, amphipathic polymers having units of chemical formula 41, chemical formula 42, chemical formula 43, etc. There is a substance. In the chemical formula, R ¹⁰ represents CH ₃ (CH ₂ ) ₁₇ −.

[0068]

[Chemical 41]

[0069]

[Chemical 42]

[0070]

[Chemical 43]

A monomolecular film (LB of the amphiphilic polymer substance)
The method for producing the film is not particularly limited, but a method in which flow orientation occurs during accumulation is preferable, and the vertical dipping method is one of the preferable embodiments.

At this time, known LB film materials such as long-chain fatty acids and long-chain alcohols, and the inventors of the present invention have previously described JP-A-63.
The polymer LB film material proposed in JP-A-218727 may be mixed and used.

Before accumulating the LB film, the transparent electrode 5
It is also a desirable embodiment of the present invention to subject the glass substrates 4 and 4 on which a and the electrodes 5b are formed to a surface treatment.

Heat treatment temperature for cyclizing the amphipathic polymer having the repeating unit represented by the general formula (I) to obtain a polyimide having the repeating unit represented by the general formula (II) completely or partially. Is usually higher than the temperature required in the assembly process of the liquid crystal element 1 after forming the alignment film 6 and lower than the temperature at which the alignment film material decomposes. Within that temperature range, it is preferably in the range of 150 to 450 ° C, and more preferably in the range of 150 to 250 ° C.

The type of the liquid crystal element 1 that can be used in the present invention is not particularly limited, and the liquid crystal element 1 of the present invention is a TN type liquid crystal element using a nematic liquid crystal, an STN type liquid crystal element, a guest-host type liquid crystal element, or the like. Made and used as.

Examples of the liquid crystal 3 used in the present invention include various nematic liquid crystals and mixtures thereof. The dielectric anisotropy Δε is greater than 0 and 10 or less. Among them, it is preferable that the ratio of the spray elastic constant K1 and the bend elastic constant K3, K3 / K1, is 1.0 or more.

As a typical example of the liquid crystal 3, a specific example will be given based on a product of Merck. Examples of the liquid crystal 3 having a dielectric anisotropy Δε of more than 0 and 10 or less include ZLI-1565 developed for in-vehicle liquid crystals and ZLI-3651, ZLI-37 developed for active matrix liquid crystal elements.
71, ZLI-3788, ZLI-4287 and the like.

Spray elastic constant K1 and bend elastic constant K
As the liquid crystal 3 having a ratio of K3 / K1 of 1.0 or more, in addition to the above active matrix liquid crystal, ST
ZLI-4431, ZLI-4 developed for N liquid crystal
448 is mentioned as a preferable example.

Next, the liquid crystal element of the present invention will be described in more detail based on specific examples.

Example 1 ITO was vacuum-deposited to a thickness of 200 nm using a mask having a pattern formed on one side of a glass substrate. on the other hand,
A polyimide precursor (number average molecular weight 10000) having a unit represented by Chemical formula 44 obtained by reacting acid chloride of pyromellitic acid distearyl ester with para-phenylenediamine was prepared by using Langmuir.RTM. 1 according to the Blodgett method (LB method)
One layer was accumulated.

[0081]

[Chemical 44]

Further, the substrate was heat-treated at 180 ° C. for 1 hour. By this heat treatment, the polyimide precursor becomes
The polyimide having the unit shown by
It has very good chemical resistance and heat resistance.
The imidization ratio in this case was 20%.

[0083]

[Chemical formula 45]

Two identical glass substrates (electrode bodies) on which the alignment films have been formed by the above-mentioned treatment are prepared, and the pulling-up directions of the two substrates at the time of forming the LB film are perpendicular to each other. A cell, and as one side of the substrate, the surface on which the transparent electrode layer is formed is sealed with an acid anhydride-curable epoxy resin in which plastic beads having a diameter of 8 μm are dispersed. After printing with a width of 1 mm on the entire other circumference, the transparent electrodes were pressed against each other and heated at 140 ° C. for 3 hours for curing and adhesion. After bonding
Nematic liquid crystal (Merck, trade name Z
LI-1565: chiral agent C-15 (0.5% by weight) was injected. After the injection, the opening was fixed with a commercially available acid anhydride-curable epoxy resin and the liquid crystal was sealed to complete a TN type liquid crystal element. By heating the completed liquid crystal cell once to 100 ° C. and then gradually cooling it for initial alignment,
A cell having a good orientation state in which reverse twist or reverse tilt did not occur was obtained.

Example 2 A liquid crystal element (anti-para type liquid crystal element) was prepared in the same manner as in Example 1 except that the cell was constructed so that the pulling-up directions of the substrates at the time of forming the LB films of the two substrates were antiparallel. Was produced. When the pretilt angle of the obtained liquid crystal was measured by the crystal rotation method, it was about 10 degrees.

Examples 3 to 4 A TN type liquid crystal element (Example 3) and an anti-para type liquid crystal element (Example 3) were prepared in the same manner as in Example 1 except that the glass substrate on which the LB film was formed was heat treated at 200 ° C. for 1 hour. Example 4) was made.

The imidation ratio of the polyimide precursor LB film under the above conditions was 50%. The TN type liquid crystal element of Example 3 has no reverse tilt or reverse twist, and the pretilt angle of the liquid crystal of the anti-para type liquid crystal element of Example 4 was measured using the crystal rotation method. The pretilt angle was about 6 degrees. Met.

Example 5 ITO was vacuum-deposited to a thickness of 200 nm using a mask having a pattern formed on one side of a glass substrate. on the other hand,
A polyimide precursor (a number average molecular weight of 10,000) having a unit represented by the following formula 46 obtained by reacting acid chloride of pyromellitic acid distearyl ester with diaminoanthraquinone was prepared by the LB method on the glass substrate on which the ITO was vapor-deposited. Thus, 11 layers were accumulated.

[0089]

[Chemical formula 46]

Then, the substrate was further heat-treated at 180 ° C. for 1 hour. By this heat treatment, the polyimide precursor becomes a polyimide having a unit represented by the chemical formula 47,
The LB film comes to have very good chemical resistance and heat resistance. The imidation ratio at this time was 40%.

[0091]

[Chemical 47]

Two identical glass substrates (electrode bodies) on which the alignment films have been formed by the above-mentioned treatment are prepared, and the pulling-up directions of the two substrates at the time of forming the LB film are perpendicular to each other. A cell, and as one side of the substrate, the surface on which the transparent electrode layer is formed is sealed with an acid anhydride-curable epoxy resin in which plastic beads having a diameter of 8 μm are dispersed. After printing with a width of 1 mm on the entire other circumference, the transparent electrodes were pressed against each other and heated at 140 ° C. for 3 hours for curing and adhesion. After bonding
Nematic liquid crystal (Merck, trade name Z
LI-4287: chiral agent C-15 (0.5% by weight) was injected. After the injection, the opening was fixed with a commercially available acid anhydride-curable epoxy resin and the liquid crystal was sealed to complete a TN type liquid crystal element. By heating the completed liquid crystal cell once to 100 ° C. and then gradually cooling it for initial alignment,
A cell having a good orientation state in which reverse twist or reverse tilt did not occur was obtained.

Example 6 A liquid crystal element (anti-para type liquid crystal element) was formed in the same manner as in Example 5 except that the cell was constructed so that the pulling-up directions of the substrates at the time of forming the LB film of the two substrates were antiparallel. Was produced. When the pretilt angle of the obtained liquid crystal was measured by the crystal rotation method, it was about 8 degrees.

Comparative Examples 1-2 As a nematic liquid crystal, a product name ZLI-34 manufactured by Merck & Co., Inc.
A TN type liquid crystal element (Comparative Example 1) and an anti-para type liquid crystal element (Comparative Example 2) were produced in the same manner as in Example 1 except that 05 (K3 / K1 = 0.79) was used.

In the obtained TN type liquid crystal element of Comparative Example 1, reverse tilt occurred during driving. In addition, Comparative Example 2
The pretilt angle of the liquid crystal in the anti-para type liquid crystal element of 0.
It was 3 degrees.

[0096]

As described above, according to the present invention,
It is possible to obtain a liquid crystal element which has an alignment film formed without performing a rubbing treatment and has no display defects such as reverse twist and reverse tilt.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an embodiment of a liquid crystal element of the present invention.

FIG. 2 is a schematic cross-sectional view of a conventional liquid crystal element.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Liquid crystal element 2a, 2b Electrode body 3 Liquid crystal 4 Glass substrate 5a Transparent electrode 5b Electrode 6 Alignment film

Claims (3)

[Claims] 1. An electrode body comprising a glass substrate, a transparent electrode formed on the glass substrate, and an alignment film formed on the surface of the transparent electrode; a glass substrate; and an electrode body formed on the glass substrate. A liquid crystal element comprising another electrode body comprising an electrode and an alignment film formed on the surface of the electrode, and a liquid crystal disposed between the two electrode bodies, wherein the alignment film is on the water surface. A Langmuir-Blodgett film obtained by laminating one or more layers of the monomolecular film formed on the surface of the glass substrate on which the transparent electrode and / or the electrode is formed, and the dielectric constant of the liquid crystal. Rate anisotropy Δε is 0
A liquid crystal device having a larger value of 10 or less. 2. The liquid crystal device according to claim 1, wherein a ratio of a splay elastic constant K1 and a bend elastic constant K3 of the liquid crystal, K3 / K1, is 1.0 or more. 3. The alignment film has the general formula (I) (Chemical Formula 1): Where R ¹ has at least 2 carbon atoms and 4
A valent group, R ² is ² having at least 2 carbon atoms
The valent groups R ³ , R ⁴ , R ⁵ and R ⁶ are each an aliphatic, cycloaliphatic or aromatic which may be substituted with a halogen atom, a nitro group, an amino group, a cyano group, a methoxy group or an acetoxy group. It is a monovalent group having 1 to 30 carbon atoms or a hydrogen atom of a group (which may be combined with each other), and at least one of R ³ , R ⁴ , R ⁵ and R ⁶ is a halogen atom, nitro. Group, an amino group, a cyano group, a methoxy group, an optionally substituted aliphatic, cycloaliphatic or aromatic (which may be combined with each other) monovalent C12 to C30 A monomolecular film obtained by developing an amphiphilic polymer substance having a repeating unit represented by the group) on the water surface, on the surface of the glass substrate on which the transparent electrode and / or the electrode is formed. After stacking one or more layers, Amphipathic polymer material, fully or partially the general formula (II) (Formula 2): ## STR2 ## ^3. A thin film obtained by subjecting a thin film to heat treatment to obtain a polyimide having a repeating unit represented by the formula (wherein R ¹ and R ² are the same as above). Liquid crystal element.