JPH01251345A - Optical recording element - Google Patents

Abstract

PURPOSE:To eliminate the lowering of resolution with lapse of time due to fluidity by providing a liquid crystal layer through a molecular layer of compound which makes a structural change reversibly by light on a transparent substrate whose surface is finely deformed. CONSTITUTION:The title element is constructed to sandwich a liquid crystal layer 3 between two substrates 1 which have monomolecular layer 2 of the photochromic compound and whose surfaces are finely deformed. When light is projected on one part A, the photochromic compound makes the structural change, therefore, the vertical arrangement of the part is destroyed and liquid crystal makes an arrangement parallel to the surface. Consequently, when this photo recording element is put between two polarizers whose polarizing axes are perpendicular to each other, parts B on which the light is not projected are dark, however, the part A on which the light is projected becomes bright and a clear picture can be obtained. Since the polarization of a wavelength which does not generate photochromism can be used for reading information, the information is not destroyed. Thus, the lowering of the resolution with lapse of time due to the liquid crystal having the fluidity is eliminated.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a novel optical recording element that utilizes the change in orientation of liquid crystal caused by light. More specifically, the present invention relates to an element that causes a reversible structural change by light and uses this to record information temporarily or permanently.

Conventional technology As a recording element using a liquid crystal, information can be stored electrically.
The former is mainly used for display purposes.

By the way, LCD displays that use electrical effects to write information lose their information when the power supply stops.
To preserve this permanently, special measures must be taken, and since patterned electrodes are used, the resolution is low and it is unsuitable for use as a high-capacity recording element.

On the other hand, devices that use heat such as laser beams to store information using the action of light can be applied to high-density optical recording, but are limited to bit recording.
The scope of its use is inevitably limited. In addition, a type that mixes a compound whose structure changes photochemically and changes the phase due to the action of light shows excellent resolution for the first time after inputting information, but because the liquid crystal flows, it takes about 1 hour. There is a tendency for resolution to drop significantly over time. for example.

The photochromic cholesteric liquid crystal obtained by dissolving chiral azobenzene in a nematic liquid crystal changes to an isotropic phase under the action of ultraviolet light, and this can be used to record information, but the liquid crystal loses strength over the course of 2 hours. It flows and the recorded image becomes unclear. (Refer to the proceedings of the 52nd Spring Annual Meeting of the Chemical Society of Japan, 1986).

Problems to be Solved by the Invention The present invention is an optical recording system that records information using changes in the orientation of liquid crystals caused by light, and that does not cause a decrease in resolution over time due to the fluidity of the liquid crystal. This was done for the purpose of providing an element.

Means for Solving the Problems The inventors of the present invention have conducted extensive research in order to develop an optical recording element that utilizes the change in the orientation of liquid crystals caused by light. By creating a molecular layer of a compound that causes a change and placing a liquid crystal layer on top of that molecular layer, liquid crystals can be reversibly and rapidly transmitted in accordance with the two structures of the compound that change reversibly with light. It was discovered that the liquid crystal layer does not change and information is retained for a long period of time unless the state of light changes, and based on this knowledge, the present invention was accomplished.

That is, the present invention provides an optical recording element in which a liquid crystal layer is provided on a transparent substrate whose surface is minutely deformed, with a molecular layer of a compound that undergoes a reversible structural change when exposed to light.

The transparent substrate in the present invention is a sheet of ordinary silica glass, hard glass, quartz, various plastics, etc., or silicon oxide on the surface thereof.

Tin oxide, indium oxide, aluminum oxide.

Those coated with metal oxides such as titanium oxide, chromium oxide, zinc oxide, or silicon nitride or silicon carbide are used.

Normally, a liquid crystal is used as a sandwich structure filled between two substrates, but in the present invention, at least one of these two substrates may be a transparent substrate, and the other may be made of copper or iron. It can also be a sheet of metal such as aluminum, platinum, or a sheet coated with these metals. These substrates are normally used as sheets with a smooth surface and a thickness of 0.01 to 1 m+n.

In the present invention, the above substrate is prepared in advance.

The surface is finely deformed according to a known method.

This substrate surface deformation treatment method includes a rubbing method in which the substrate surface is lightly rubbed in one direction with a cotton cloth, etc., and an oxide such as silicon oxide, which is an alignment agent, is applied several hundred times diagonally to the substrate surface.
There is an oblique vapor deposition method in which the film is vapor-deposited to a thickness of several thousand layers (Matsumoto Tsutsu-1, co-authored by Ichiyoshi Kakuda, ``Latest Technology of Liquid Crystals'', Kogyo Kenkyukai (1983)). next.

It is necessary to provide a molecular layer of a compound whose structure undergoes a reversible structural change when exposed to light on a substrate whose surface has been treated in this way, and photochromic compounds are most commonly used as this compound.

This photochromic compound is a compound that undergoes structural changes under the action of light and changes its behavior with respect to light, such as color tone, and has so far been a carbon-carbon compound.

Tanyasu and Shigema, light diagram of unsaturated double bond between nitrogen and nitrogen
A wide variety of compounds are known that utilize I isomerization reactions, valence photoisomerization reactions, heterolytic photocyclic ring closure reactions, photoring closure reactions, phototautomerization reactions, and the like. [For example, see Photochromism J (1971) published by Wiley Interscience, G.H., Brown Hato]
. Among such compounds, examples of photochromic compounds based on photogeometric isomerization include azobenzene, indigo, acylindigo, thioindigo, and selenoindigo.

Examples of photochromic compounds based on a heterolytic photocyclic ring closure reaction include berinaphthoindigo, hemiindigo, hemitioindigo, azomethine, etc. , indolinospilobenzothiopyran, spiroindolizine, etc., as examples of photochromic compounds based on photocyclization reactions.

Stilbene, fulgide etc. are also examples of photochromic compounds based on the mutagenesis reaction.

Salicylideneanyl, O-hydroxyazobenzene, 0
Compounds each having a basic skeleton such as -nitrobenzyl can be mentioned.

In the present invention, a molecular layer of such a photochromic compound can be provided on a substrate by a method commonly used for vertical alignment of liquid crystals9, for example, a method of treating the substrate with a photochromic compound having a surface active group, at least 1
A method of treating the substrate surface with a photochromic compound having a silyl group substituted with halogen atoms or an alkoxy group, a method of treating the substrate surface with a silylating agent having an amino group, and then bonding a photochromic compound having a carboxyl group, etc. Therefore, it can be done [Jay, Cogner (J,
Cognard), [Molecular Crystals]
and Liquid Crystals (MolecuIar)
Crystals and Liquid Crys
tals) J, Supplmen) 1 (1982)
and "Latest Technology of Liquid Crystals" mentioned above.

reference〕.

Examples of the surface-active group of the photochromic compound having the above-mentioned surface-active group include carboxylic acid residue, makirubi'-LQ
'=+um salt residues, carboxylatochromium complex residues, ester residues, nitrile residues, urea residues, amine residues, alcohol residues, phenol residues, 9 betaine residues, and the like.

To apply a photochromic compound with such surface-active groups to the substrate surface, it can be applied directly to the substrate surface, or
Alternatively, it may be used by dissolving it in a liquid crystal substance.

In the latter case, the amount of the photochromic compound having one surface active group added is in the range of 0.01 to 5.0% by weight, preferably 0.5 to 3.0% by weight, based on the weight of the liquid crystal.

Examples of the photochromic compounds having a silyl group substituted with at least one halogen atom or an alkoxy group include triethoxysilyl azobenzene, monochlorojethoxysilyl azobenzene, trichlorosilylazobenzene, triethoxysilyl indigo, triethoxysilyl indigo, and triethoxysilyl indigo. Examples include linospirobenzobilane. Treatment with these compounds is carried out by applying to the substrate surface as a solution at a concentration ranging from 0.1 to 10%, preferably from 0.5 to 5%, or by immersing the substrate in this solution. . The solvent at this time is water,
Acetic acid, toluene, acetone, dimethylformamide, etc. are suitable. Further, the processing time is usually 30 seconds to 10 minutes, ranging from 1 second to 1 hour. In this method, the bonding strength can be further improved by treating the surface of the substrate with a silylating agent.

Next, the substrate surface is treated with a silylating agent having 7 amino groups, and then treated with a photochromic compound having a carboxyl group. Examples of silylating agents used include aminopropyltriethoxysilane, aminopropyljethoxysilane, etc. , aminobutylmethyljethoxysilane, aminobutyltriethoxysilane, etc. Treatment with these silylating agents can be carried out by forming a solution with a concentration in the range of 0.1 to 10%, preferably 0.5 to 5%, and applying this solution to the substrate surface or immersing it in this solution. It is done by doing. The solvent in this case is ' al
Tanol, acetic acid, toluene, acetone.

After treatment with this silylating agent, amine 7 of the silylating agent
The group is reacted with a photochromic compound having a carboxyl group according to a conventional method to form an amide bond. In this way, photochromic compounds can be chemically bonded onto the substrate surface.

bond onto the substrate surface. A compound that undergoes a reversible structural change when exposed to light can sufficiently exhibit its function by forming a monomolecular layer, but it can also be formed into a bimolecular layer or more if desired.

Next, as the liquid crystal for the liquid crystal layer provided on the molecular layer of the compound that undergoes a reversible structural change when exposed to light, any liquid crystal material is selected from among the conventionally known nematic, smectic, and cholesteric liquid crystal materials. However, in the case of smectic liquid crystal materials, it is necessary to choose one that takes a nematic liquid crystal phase at a certain temperature. It goes without saying that liquid crystal substances include not only low molecular weight substances but also high molecular weight substances.

Such liquid crystal materials are 1, for example, Nie Pekin (^, Be
quin) et al., “Molecular Crystals and Liquid Crystals”
ystals and 1quid crystal
s) J, Volume 115.

It is listed on the first page. Polymer liquid crystal materials are available from, for example, Advances in Polymer Science (
Advances in Polymer 5cien
ce), Volume 60/61 (1984). These liquid crystal substances may be used alone or in combination of two or more.

Furthermore, dichroic dyes, antioxidants, and the like may be added to the liquid crystal material. As a dichroic dye, for example, Naotake Matsuzawa, "Dyeing Industry", Vol. 32, 215 pages (1984"
) are used.

In this case, if you use a temperature-dependent liquid crystal material, for example, a liquid crystal material that does not change its structure when irradiated with light at room temperature, but undergoes a structural change when heated above a certain temperature, it is possible to develop dichroism. The present invention will now be described in further detail with reference to the accompanying drawings.

FIG. 1 is a cross-sectional view showing the basic structure of the present invention. A molecular layer 2 of a compound that undergoes a reversible structural change when exposed to light is fixed on a transparent substrate 1 whose surface has been minutely deformed, and it also prevents dissipation. This is further covered with a substrate to prevent damage. This substrate may be transparent or opaque,
It is also possible to use a material whose surface is coated with a molecular layer of a compound that undergoes a reversible structural change when exposed to light, or a material whose surface is coated with a homogeneous alignment layer that has the effect of aligning liquid crystals parallel to the surface. can.

FIG. 2 is a cross-section showing an example of a preferred embodiment of the invention, between two substrates 1 having a monomolecular layer 2 of a photochromic compound on the surface.

It has a sandwich structure with a liquid crystal layer sandwiched between them.

Two substrates are constructed such that the directions in which one surface is minutely deformed are parallel to each other. In this figure, ■ indicates the state before light irradiation, and ■ indicates the state after light irradiation.

Before irradiation with light, the liquid crystals are regularly arranged in a direction perpendicular to the substrate surface (homeotropic gamma direction) due to the action of the monomolecular layer of the photochromic compound. (1).

Next, when part (2) of this optical recording element is irradiated with light.

Because photochromic compounds undergo structural changes.

The above-mentioned vertical alignment in that portion is destroyed, and the liquid crystal assumes a parallel (homogeneous) alignment to the surface. In the photochromic compound monomolecular layer whose structure has been changed by light in this way, if the surface is slightly deformed in advance, the long axes of the liquid crystals will be aligned in the same direction parallel to the surface. 1 was discovered for the first time by the present inventors.

Therefore, if this optical recording element is sandwiched between two polarizers whose polarization axes are perpendicular to each other, the area that is not irradiated with light (c)
The area is dark, but the areas illuminated by light become brighter and a clear image can be obtained. Since polarized light at a wavelength that does not cause photochromism can be used to read information, the information will not be destroyed.

Next, '3. The figure differs from the case of Figure 2 in that it is
, fl The two substrates are constructed so that the directions in which the proverb M is minutely deformed are orthogonal to each other.

In this case, since the light irradiated part becomes a twisted nematic phase, an optically clear image can be obtained by a known method.

Next, FIG. 4 shows an example of an embodiment different from those shown in FIGS. 2 and 3, and is an example in which a homogeneous alignment layer 4 is provided on one of the two substrates.

This homogeneous alignment layer can be provided by rubbing the surface of the substrate with polyvinyl alcohol, polyimide resin, polyoxyethylene, etc., or by obliquely vapor-depositing an oxide such as S10□.

In this example, on the photochromic compound monomolecular layer side, the liquid crystals are aligned in a direction perpendicular to the substrate surface, as shown in Figure 4I, but on the homogeneous alignment layer side, they are aligned in a direction parallel to the substrate. It has a structure. When this is irradiated with light, the liquid crystals in the irradiated portion (2) are aligned parallel to the monomolecular layer of the photochromic compound, so the whole becomes homogeneously aligned, and information can be read out in the same manner as above. Can be done.

In the optical recording element of the present invention, if it is desired to erase the information once recorded, it can be done by irradiating it with light having a different wavelength from the light used during recording to restore the structure of the photochromic compound.

Effects of the Invention The optical recording element of the present invention has the advantage that it does not exhibit the disadvantages of information recording using conventional photochromic materials, such as the disadvantage that once recorded information gradually disappears due to repeated reading, Since the alignment of the liquid crystals is controlled by a photochromic monolayer, the resolution of liquid crystals with a fluid phase is much better than that of conventional liquid crystals in which photochromic compounds are added.

Furthermore, the optical recording element of the present invention is not only used for reversible optical information storage, but also for optically addressable display.The present invention will be explained in more detail with reference to the following examples.

Example 1 4-hexyl-4°-hydroxyazobenzene (1)
1 g (3,73Xl0-'mol) was made into a sodium salt with sodium methylate, and then 2-tetrahydropyranyl 6-bromohexanony) was added to the sodium salt (1.03
g (3,69X 10-3 mol) and 5 mj of dimethylacetamide! was added and heated at 100°C for 73 hours.

After the reaction was completed, water was added and the mixture was allowed to cool to room temperature, and the precipitated yellow crystals were collected by filtration. Extract this with ethyl acetate,
After drying over magnesium sulfate, the solvent was distilled off under reduced pressure.

The residue was recrystallized from a mixture of hexane and benzene to obtain 1 g of 6-(4-(4-hexylphenylazo)-phenoxy)-hexanoic acid. 200m of this carboxylic acid
g (5,05XIQ-'mol) of thionyl chloride 5m
After heating under reflux for 2 hours, excess thionyl chloride was distilled off and 3 mf of dry ether was added to the mixture. and triethylamine 0.1
Add 5 g (1,485×10-'mol). To this mixture was added dropwise a solution of 0.11 g (4,98 x 10-' mol) of triethoxyaminopropylsilane in dry ether under water cooling, and the mixture was stirred for 2 hours and then filtered under a nitrogen atmosphere to remove salts. Thereafter, the solvent was distilled off at room temperature under reduced pressure. 213 mg of yellow waxy N-(3-)ethoxysilylbrobyl)-6-(4-(4-hexylphenylazo)phenoxy)hexanoic acid amide was obtained.

Q of this 1:9wt/wt mixture of triethoxysilylazobenzene and ethyltriethoxysilane, 4w
A clear quartz plate (IX30ffl), which had been previously rubbed in one direction with a cotton cloth, was immersed in the t% ethanol solution for 10 minutes, air-dried, and then dried at 100° C. for 10 minutes.

Both sides of this quartz plate are modified with azobenzene,
Its absorption luminous intensity at 340 nm was 0.010, and it was actually colorless and transparent. Two quartz plates treated in this way sandwich a cis-1 tanxanecarboxylic acid phenyl ester-based knee mixed liquid crystal (K-17-N-73-1) whose rubbing directions are the same, and then coated with epoxy resin. It was sealed to create a sandwich cell.

This colorless and transparent cell is placed between crossed nicols, and He-N
e The amount of transmitted light was monitored using a laser. The amount of transmitted light in the cell before UV irradiation was zero under crossed Nicols conditions, indicating that the cell was oriented toward homeotropic liquid crystal alignment. 36 to this
When irradiated with 5 nm ultraviolet light, the amount of transmitted light increased as azobenzene photoisomerized from trans to cis.

At this time, it can be seen that when the direction of the rubbing treatment is 45 degrees with respect to the polarizer, the amount of transmitted light is the largest, indicating homogeneous alignment. Next, when visible light of 440 nm or more was irradiated, the amount of transmitted light decreased again as trans isomerization occurred. The amount of transmitted light changed reversibly in response to alternate irradiation with ultraviolet light and visible light.

When the same cell was irradiated with ultraviolet light through a negative, a clear image with crossed Nicols was observed.

This image remained undisturbed even when pressure was applied to the cell to cause the liquid crystal to flow.

Example 2 Triethoxysilylazobenzene obtained in Example 1 and aminopropyltriethoxysilane were mixed at a weight ratio of 1:9, and a quartz plate was prepared by rubbing with this 4 wt% ethanol solution. After processing in the same manner as in Example 1, the two quartz plates constituted an 8 μm mixed liquid crystal sandwich cell.

When this cell was alternately irradiated with ultraviolet rays and visible light, a reversible change in the amount of transmitted light was observed under crossed Nicols conditions. After the entire surface was irradiated with ultraviolet rays, a clear image was obtained when the film was exposed to 488 nm light from an Ar laser through a negative film.

Example 3 The azobenzene-treated quartz plate obtained in Example 1 and the quartz plate coated with polyvinyl alcohol and rubbed had a thickness of 8μ.
A sandwich cell of mixed liquid crystal of m was constructed. At this time, a change in the amount of transmitted light was observed in the rubbing direction of the 1 quartz plate and in the rubbing direction of the polyvinyl alcohol-coated quartz plate. It was found that there is a reversible change between homeotropic and hybrid orientations.

Example 4 A silylating agent was produced in the same manner as in Example 1 except that 4-hydroxyazobenzene was used instead of 4-hexyl-4°-hydroxyazobenzene.

A quartz plate that had been previously rubbed was treated.

When we alternately irradiated ultraviolet rays and visible light onto a cell sandwiching a mixed liquid crystal using this quartz plate so that the rubbing process was parallel, we observed a reversible change in the amount of transmitted light under crossed Nicols conditions.

Example 5 A silylating agent was produced in the same manner as in Example 1 using 4-methyl-4°-hydroxyazobenzene instead of 4-hexyl-4′-hydroxyazobenzene, and a quartz plate was subjected to a rubbing treatment in advance. processed. When a cell sandwiching a mixed liquid crystal between quartz plates was alternately irradiated with ultraviolet rays and visible light, a reversible change in the amount of transmitted light was observed under crossed Nicols conditions.

Example 6 A silylating agent was produced in the same manner as in Example 1 using 4-cyclohexyl-4'-hydroxyazobenzene instead of 4-hexyl-4'-hydroxyazobenzene, and was subjected to a rubbing treatment in advance. Treated quartz plate. When we alternately irradiated ultraviolet rays and visible light onto a cell in which a mixed liquid crystal was sandwiched between the quartz plates so that the rubbing directions were parallel to each other, a reversible change in the amount of transmitted light was observed under crossed Nicols conditions.

Example 7 A q:bl damp rubbing treatment was performed using a silylating agent produced using 4-octyl-4゜-hydroxyazobenzene instead of 4-hexyl-4゛-hydroxyazobenzene in Example 1. When a cell was constructed by surface-treating a quartz plate and sandwiching a mixed liquid crystal so that the rubbing directions were parallel, the amount of transmitted light changed reversibly by alternating irradiation with ultraviolet and visible light.

Example 8 A quartz plate that had been rubbed in advance by a known method was treated with an ethanol solution of aminopropyltriethoxysilane to prepare aminoquartz.

The azobenzenecarboxylic acid chloride obtained in Example 1 was dissolved in methylene chloride, an amino quartz plate was immersed in this solution, and triethylamine was added.

It was left at room temperature for 1 hour. This quartz plate was washed with methylene chloride and ethanol, and dried at 100° C. for 10 minutes. It was confirmed by an ultraviolet-visible spectrophotometer that an azobenzene group was bonded. This mixed liquid crystal cell is composed of two quartz plates modified with azobenzene so that the rubbing directions are parallel to each other.

The amount of transmitted light changed reversibly by alternating irradiation with ultraviolet and visible light.

Example 9 4-h-1-cyl-4°-hydroxyazobenzene 0.
4g and a catalytic amount of trimethylbenzylammonium hydroxide in 2ml of benzene! to which acrylonitrile 8- was slowly added. After heating for 22 hours, the solvent was distilled off under reduced pressure, and the residue was extracted with benzene. Next, silica gel column chroma H: 1 lL, 2-
0.25 g of (4-hexylphenylazo)-phenoxy)propanenitrile was obtained. This was hydrolyzed with acetic acid containing hydrochloric acid to obtain the corresponding carboxylic acid. This was converted into an acid chloride with thionyl chloride, and an amino quartz plate was treated with this in the same manner as in Example 8. From its absorption spectrum, it was confirmed that azobenzene was bound.

The rubbing directions of these two quartz plates are perpendicular to each other.

The mixed liquid crystal cell constructed in this way was made homeotropic and lit by alternating irradiation with ultraviolet rays and visible light.

Example 10 Q, 4wt of a 1:29wt/wt mixture of azobenzene and triethyltriethoxysilane prepared in Example 1
A quartz plate that had been previously rubbed with a solution of 10% was treated in the same manner. The rubbing directions of these two quartz plates are parallel to each other, so that 4-octyl-4°-cyanobiphenyl (K-21-S), which is a smectic liquid crystal layer, is formed at room temperature.
-33-'N-40-1) sandwich cell (cell thickness: 8 μm) was constructed. No phase change was observed in the liquid crystal when room temperature water (approximately 20°C) was irradiated with ultraviolet rays, but when the cell was heated to 35°C and then irradiated with ultraviolet rays, there was a change in the amount of transmitted light under crossed Nicols conditions. was recognized. An image obtained by passing a negative through this cell and irradiating it with ultraviolet rays at 35° C. remained stable for 6 months at room temperature. This image did not disappear even when the cell was irradiated with visible light. From this, a memory effect due to the smectic liquid crystal was recognized.

Example 11 The azobenzenecarboxylic acid obtained in Example 1 was added to the mixed liquid crystal.
．． When a cell was constructed by dissolving it at 5% by weight and sandwiching it between two glass plates using a 12 μm glass spacer, the amount of transmitted light was zero under crossed Nicol conditions, indicating homeotropic alignment. Do you get it. When this cell was irradiated with ultraviolet light through a negative image, an image was observed under crossed nicols.

As a result of irradiating this with visible light, one image immediately disappeared.

Example 12 2-tetrahydropyranyl-4-instead of 2-tetrahydropyranyl-6-bromohexanoate in Example 1
A silylating agent was produced in the same manner using bromobutanoate, and a glass plate that had been previously subjected to a rubbing treatment was treated. When a cell sandwiching the mixed liquid crystal used in Example 1 with this glass plate was alternately irradiated with ultraviolet rays and visible light, a reversible change in the amount of transmitted light was observed under orthogonal Nico.

Example 13 Using ethyl chloroacetate in place of 2-tetrahydropyranyl-6-bromohexanoate in Example 1, 2-
After synthesizing and hydrolyzing ethyl (4-(4-hexylphenylazo)phenoxy)acetate, a silylating agent was produced in the same manner, and a glass plate that had been previously subjected to a rubbing treatment was treated. From its absorption spectrum, it was confirmed that azobenzene was bound. When a cell in which a mixed liquid crystal was sandwiched between the glass plates was alternately irradiated with ultraviolet rays and visible light, a reversible change in the amount of transmitted light was observed under crossed Nicols conditions.

Example 14 A silylation agent was produced by using 3-aminopropylmethyljethoxysilane instead of triethoxyaminopropylsilane in Example 1 and amidation with dicyclohexylcarbodiimide in methylene chloride. A glass plate that had been previously subjected to a rubbing process was treated in the same manner, and the mixed liquid crystal was made into a sandwich cell using this glass plate.

When this homeotropically aligned cell was alternately irradiated with ultraviolet light and visible light, a reversible change in the amount of transmitted light was observed under crossed Nicols conditions.

Example 15 A silylation agent was produced by using 4-aminobutyltriethoxysilane instead of triethoxyaminopropylsilane in Example 1 and amidation with dicyclohexylcarbodiimide in methylene chloride. When a glass plate that had been previously rubbed in the same manner was silylated and a cell in which a mixed liquid crystal was sandwiched between the glass plates was alternately irradiated with ultraviolet rays and visible light, a reversible change in the amount of transmitted light was observed under crossed Nicols conditions. Ta.

Example 16 Instead of triethoxyaminopropylsilane in Example 1, 4 S'+! By performing amidation with dicyclohexylcarbodiimide in methylene chloride using butyldimethylmethoxysilane.

A silylating agent was produced. This silylation agent is used to treat glass that has been previously rubbed.

A cell sandwiching mixed liquid crystals was created. This cell was placed between crossed nicols, and the amount of transmitted light was monitored using He- and Ne lasers. The amount of transmitted light under crossed nicols decreased as azobenzene photoisomerized from trans to cis. Next, when visible light of 440 nm or more was irradiated, the amount of transmitted light increased again as photoisomerization to trans occurred.

The amount of transmitted light changed reversibly in response to alternate irradiation with ultraviolet light and visible light.

Patent applicant Kozo Iizuka, Director-General of the Agency of Industrial Science and Technology
l Figure 3 (I) (II) Procedural amendment (method) % formula % 1. Indication of the case 1988 Patent Application No. 077786 2. Name of the invention Optical recording device 3. Person making the amendment Related Patent Applicant: 1-3-1 Kasumigaseki, Chiyoda-ku, Tokyo (+14) Director of the Agency of Industrial Science and Technology Sachi Iizuka 34, Designated Agent 5, Date of Procedural Amendment Directive: June 8, 1986 (Despatch: Showa June 28, 1963) 6. Number of inventions increased by amendment 0 7. Target of amendment 8. Contents of amendment (1) The following items and explanations will be added from line 14 on page 28 of the specification. .

"

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view showing an example of the structure of an optical recording element of the present invention, in which reference numeral 1 denotes a substrate whose surface is minutely deformed;
2 is a molecular layer of a compound that undergoes a reversible structural change when exposed to light, and 3 is a liquid crystal layer. FIG. 2 is a cross-sectional view showing another example and the arrangement state of the liquid crystal before and after light irradiation, and the two substrates designated by reference numeral 1 are arranged so that the directions in which their surfaces are minutely deformed coincide. . Reference numerals 2 and 3 respectively indicate the same layers as above. FIG. 3 is a cross-sectional view showing yet another example and the arrangement state of the liquid crystal before and after light irradiation, and the two substrates 1 and 4 are arranged so that the directions in which their surfaces are minutely deformed are perpendicular to each other. It is located in 2.3 indicates the same layer as above. FIG. 4 is a cross-sectional view showing another example and the alignment state of liquid crystal before and after light irradiation, in which reference numeral 1 is a substrate whose surface has been minutely deformed, 4 in this drawing is a homogeneous alignment layer, The liquid crystals on each surface are arranged in parallel. Reference numeral 2.3 is the same layer as above. ”

Claims (1)

[Claims] 1. An optical recording element in which a liquid crystal layer is provided on a transparent substrate whose surface has been minutely deformed, with a molecular layer of a compound that undergoes a reversible structural change when exposed to light.