JPS61156122A - Recording medium - Google Patents

Abstract

PURPOSE:To obtain such a high density recording medium which induces a chemical change or physical change in a molecular unit by providing the monomolecular film of a chelate compd. having the C=N bond which desorb metallic ions or metallic atoms by syn-anti isormerization when applied with the rays of light or the cumulative film thereof and electrodes. CONSTITUTION:The chelate coordinate molecular film cumulated with the trans-type chelate coordinate molecules 2 to two layers is formed on a glass substrate 5 on which a transparent electrode 7 is deposited by evaporation. The substrate constituted by fetching metallic ions (or metallic atoms) 3 on the glass substrate 5 on which another transparent electrode 7 is deposited by evaporation and laminated with a fatty acid 4 is formed and is disposed to face the above-mentioned substrate. A bias voltage is applied between both electrodes and cis type isomerizing light 6 consisting of the light such as UV rays and visible light which can supply the energy necessary for isomerization is irradiated thereto according to a certain pattern. Then the photoisomerization reaction arises in the irradiated part where the transfer to the syn-type chelate coordinate molecules arises and the metallic ions 3 are fetched to permit the recording of information. Monitor light 10 is then irradiated to a recording medium and the change in the absorption of the light is read from transmitted light 9, 9' by which the recording is reproduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a recording medium in which recording is performed using chemical or physical changes in a monomolecular film or a monomolecular layer stack of chelate ligand molecules.

[Prior Art] Various types of recording media having recording layers made of organic compounds are known.

For example, optical recording media in which a thin film of an organic compound is used as a recording layer are also disclosed in, for example, JP-A-58-18948 and JP-A-58-125248. All of them relate to laser recording media in which recording layers are made of organic dyes and recording and reproduction are performed using laser beams. In particular, the medium disclosed in JP-A-58-125248 uses a thin film of a cyanine dye represented by as a recording layer. A cyanine dye solution represented by the general formula CI) is coated onto a plastic substrate to a thickness of 100 OA or less, for example about 300 OA, using a spin coater or the like to form a thin film. If the molecular distribution and orientation within the film is random, light scattering occurs within the film upon light irradiation, and when viewed microscopically, the degree of chemical reaction that occurs each time the film is irradiated differs. Therefore, as a recording medium, it is desirable that the molecular distribution and orientation within the film be uniform, and the film thickness is required to be as thin as possible in order to achieve high density recording. However, when using the coating method, the film thickness is limited to about 300, and it is difficult to solve the problem that the molecular distribution and orientation within the film are random.

A diacetylene compound cumulative film, which has been proposed as a resist material with high photon efficiency and excellent resolution, has been used not only as a resist material but also as a thin film electrical
JP-A-58-42229, JP-A-58-43220, etc. show that it can be applied to optical devices, electro-acoustic devices, piezo-pyroelectric devices, etc.

Recently, Japanese Patent Application Laid-Open No. 111029/1983 discloses an improvement in the method for producing a diacetylene compound cumulative film. The diacetylene compound cumulative film on the substrate produced according to the invention can be polymerized by irradiation with ultraviolet rays to form a diacetylene compound polymer film, or masked and irradiated with ultraviolet rays to partially polymerize and remove the unused material. The overlapping portions are removed to create shapes, which are used as thin film optical devices and integrated circuit elements.

However, all of these are limited to diacetylene compounds, and there is no mention of the possibility of erasing once recorded data when used as a thin film optical device.

On the other hand, in order to solve the above-mentioned drawbacks, a monomolecular film or a monomolecular layer stack of one type of photopolymerizable monomer having a parent tree group, a hydrophobic group, and at least one unsaturated bond in the molecule is formed on a substrate. An optical recording medium which can be used repeatedly is disclosed in Japanese Patent Application No. 190932/1983, which is characterized in that it has an R layer.

Whether it is a cumulative film of these diacetylene compounds, a monomolecular film or a monomolecular layer cumulative film of photopolymerizable olefin monomers, a parent group or a hydrophobic group is introduced into a photoreactive compound and the film is directly deposited on a substrate. Adopts a manufacturing method that allows it to be supported. Therefore, not only is it difficult to easily produce various functional films, but also there is a fear that photoreactivity may decrease due to the introduction of parent groups and hydrophobic groups. Furthermore, there is a problem in that an extremely complicated operation is required for controlling the molecular orientation within the film plane, which is important when performing extremely advanced high-density recording.

[Problems to be Solved by the Invention] The present invention solves the drawbacks of the conventional examples, and provides 1) a method for relatively easily producing various functional films, and 2) a method for producing various kinds of functional molecules. Even if the function becomes thinner,
3) A method of forming a film so that the film is developed without loss or deterioration, and 3) without performing any special operation in the above-mentioned film formation.

The present invention was achieved as a result of various studies on methods for aligning film constituent molecules with a highly ordered structure in the in-plane direction of the film. Furthermore, by using such a film forming method, it has become possible to easily provide a high-sensitivity, high-resolution recording medium with high quality.

An object of the present invention is to provide a high-density recording medium that undergoes chemical or physical changes in molecular units due to external factors.

Another object of the present invention is to provide a medium that is superior to conventional examples in terms of molecular orientation within the medium plane, which is an important factor when performing high-density recording on a molecular basis. Furthermore,
In manufacturing the above-mentioned recording medium, it is an object of the present invention to provide a medium having various properties through relatively simple operational changes.

[Means for Solving the Problems] and [Operation] The above objects of the present invention are achieved by the present invention as described below.

A recording medium comprising a monomolecular film of a chelate ligand molecule having a C=N bond that undergoes anti-syn isomerization and desorbs metal ions or metal atoms when exposed to light, or a cumulative film thereof, and an electrode. be.

In the present invention, desorption of metal ions or metal atoms refers to the uptake or release of metal ions or metal atoms,
This also means that both cannot be performed at the same time.

The substance constituting the recording layer of the present invention has a woody site in the molecule,
It consists of a molecule each possessing at least one hydrophobic site, at least one chelating ligand, and at least one site for syn-anti isomerization.

The recording medium of the present invention is formed by forming a monomolecular film or a monomolecular cumulative film of such molecules on a carrier. Components that can form hydrophilic sites and hydrophobic sites include various types of parent groups and hydrophobic groups that are generally widely known. Chelate ligands include, for example, hydroxyl groups, carbonyl groups, ether groups, carboxyl groups, ester groups, amino groups, nitrile groups, and thioalcohol groups. It is formed by introducing at least two or more groups such as imino groups, sulfone groups, and sulfinyl groups.

Chelate ligand molecules are represented by general formulas 1 to ■n. still,
The substitution site of the chelate ligand and the long-chain alkyl group is not limited to the positions shown in the formula. R: Long-chain alkyl group R': H, CH3, C2H5, ClCH3.

The first expression L (L L That is, having a hydrophilic site and a hydrophobic site in one molecule) means, for example, in the above general formula, the hydrophobic site is an alkyl chain, and the hydrophilic site is a chelate ligand. and other moieties.When introducing a hydrophobic moiety, a long-chain alkyl group having 5 to 30 carbon atoms is particularly preferred.

Specific examples of chelate ligand molecules in the present invention include compounds represented by the following formulas (13) to (23). However, in formulas (13) to (23), CH2-CH2F]:/\ is shown.

Table 2 CH2 C) 12 0M0 0' CH2 Oni C=0 The compounds listed above are known compounds in themselves, except that a hydrophobic moiety is introduced into the chelate ligand molecule, and
It is also known that chelating ligand molecules that are not modified with long-chain alkyl groups form chelate complexes with various metal ions.

As metal ions that can form chelate complexes with these chelate ligand molecules, those that can form a coordination bond with the chelate ligand molecules are generally desirable, such as Ag'', Gu
", Hg", Rh", K", etc.

As a method for creating a monomolecular film or a monomolecular cumulative film of chelate ligand molecules, for example, I.

The Langmuir-Prodgett method (LB method) developed by Lalgmuir et al. is used. In the LB method, for example, in a molecule with a structure that has a parent wood group and a hydrophobic group in the molecule, when the balance between the two (balance of amphiphilicity) is maintained appropriately, the molecule is placed on the water surface with the hydrophilic group facing down. This is a method of creating a monomolecular film or a cumulative film of monomolecular layers by utilizing the fact that the film becomes a monomolecular layer. When the monomolecular layer on the water surface is sparsely dispersed with 0 molecules, which have the characteristics of a two-dimensional system,
A two-dimensional ideal gas equation, nA=kT, holds between the area per molecule A and the surface pressure ■, resulting in a "gas film", where k is Portzmann's constant and T is the absolute temperature. If A is made sufficiently small, the intermolecular interaction becomes strong and a two-dimensional solid "°condensed film (or solid film)" is formed.The condensed film is transferred layer by layer to the surface of a support having various materials and shapes, such as a glass substrate. be able to. As a specific method for producing a monomolecular film of chelate ligand molecules or a cumulative film of chelate ligand molecule layers of the present invention using this method, for example, the following method can be mentioned.

First, the vertical immersion method will be explained using a film forming apparatus.

As shown in FIGS. 4(a) and 4(b), a frame 13 made of, for example, polypropylene is suspended horizontally inside a shallow and wide rectangular water tank 12 containing pure water. 21
is in charge of A float 14 made of, for example, polypropylene is floated inside the frame 13. Float 1
4 is a rectangular parallelepiped whose width is slightly shorter than the inner width of the frame 13, and is capable of two-dimensional piston movement in the left-right direction in the figure. A weight 15 is tied to the float 14 via a pulley 16 for pulling the float 14 to the right in the figure. Further, a magnet 17 fixed on the float 14 and a pair of magnets 18 which are movable from side to side in the figure above the float 14 and repel each other when approaching the magnet 17 are provided. It is possible to move left and right in the figure as well as stop. Such a weight 15 or a set of magnets 17.18
Instead, use a rotary motor or pulley to directly move the float 1.
Some move 4.

Suction nozzles 20 connected to a suction pump (not shown) via suction pipes 19 are arranged on both sides of the frame 13 . This suction nozzle 20 quickly removes unnecessary monomolecular films from the previous process on the liquid surface 21 in order to prevent impurities from being mixed into the monomolecular film or monomolecular cumulative film. It is used for. Note that 22 is a carrier that is attached to upper and lower carrier arms 23 and is vertically moved up and down.

Using the above-described film forming apparatus, metal ions are first dissolved in an aqueous phase, and target chelate ligand molecules are dissolved in a solvent. A chelate ligand molecule solution is developed on an aqueous phase to precipitate the chelate ligand molecules into a film.

Next, to prevent this precipitate from freely diffusing on the aqueous phase and spreading too much, a partition plate (or float) is installed to limit the area of development and control the state of aggregation of the membrane material, and Obtain surface pressure ■. By moving this partition plate, the developed area can be reduced to control the state of aggregation of the film material, and the surface pressure can be gradually increased to set the surface pressure (2) suitable for producing a cumulative film. By gently moving the clean carrier up and down vertically while maintaining this surface pressure, the chelate ligand molecule film is transferred onto the carrier. A chelate ligand molecule layer film is produced as described above, and a chelate ligand molecule layer cumulative film having a desired degree of accumulation can be formed by repeating the above operations.

In order to transfer the chelate ligand molecule layer onto the carrier, in addition to the above-mentioned vertical immersion method, methods such as the horizontal deposition method and the rotating cylinder method can be used. The horizontal adhesion method is a method in which the carrier is transferred by bringing it into horizontal contact with the water surface, and the rotating cylinder method is a method in which a cylindrical carrier is rotated on the water surface to transfer the chelate ligand molecule layer onto the surface of the carrier. In the vertical immersion method described above, when a carrier with a hydrophilic surface is lifted out of water in a direction across the water surface, a layer of chelate ligand molecules with the hydrophilic groups of the chelate ligand molecules facing the carrier is formed on the carrier. Ru. When the carrier is moved up and down as described above, one chelate ligand molecule layer is accumulated in each step.The direction of the film-forming molecules is reversed in the pulling step and the dipping step, so this method A Y-shaped film is formed between the layers, in which the parent wood group and the hydrophilic group of the chelate ligand molecule and the hydrophobic group and the hydrophobic group of the chelate ligand molecule face each other. On the other hand, the horizontal attachment method is a method in which the carrier is brought into horizontal contact with the water surface and transferred, and a layer of chelate ligand molecules with the hydrophobic groups of the chelate ligand molecules facing the carrier side is formed on the carrier. In this method, there is no change in the direction of the film-forming molecules even if they are accumulated, and an X-type film is formed in which the hydrophobic groups face the carrier in all layers. A side-facing cumulative film is called an X-type film.

The rotating cylinder method is a method in which a cylindrical carrier is rotated on the water surface to transfer a monomolecular layer onto the carrier surface.

The method of transferring the monomolecular layer onto the carrier is not limited to these methods, and when a large-area carrier is used, a method of extruding the carrier from a carrier roll into an aqueous phase may also be used.

Furthermore, the orientation of the aforementioned parent wood group and hydrophobic group toward the carrier is a general rule, and can be changed by surface treatment of the carrier.

The chelate ligand molecule film and the chelate ligand molecule layer cumulative film formed on the carrier by the above-mentioned method have a high density and a high degree of order, and these films can constitute a recording layer. Accordingly, it is possible to obtain a recording medium having a high-density, high-resolution recording function capable of optical recording, thermal recording, electrical recording, magnetic recording, etc. depending on the function of the chelate ligand molecule.

Next, the release and incorporation reactions of metal ions due to light-induced syn-anti isomerization of chelate ligand molecules in the recording medium according to the present invention will be explained.

1 to 3 are longitudinal sectional views showing the actual flow side of the recording medium according to the present invention. Note that each figure is a schematic diagram and does not specifically show the shape of the molecules. In Figure 1, 1
The recording medium according to the present invention is formed by forming a chelate ligand molecule film in which anti-type chelate ligand molecules 2 are accumulated in two layers on a glass substrate 5 on which ITO (transparent electrode) 7 is deposited. . On the other hand, a metal ion (or metal atom) 3 is incorporated onto a glass substrate 5 on which another ITO (transparent electrode) 7 is vapor-deposited, a fatty acid 4 is laminated to form a substrate, and both electrodes are placed opposite to the recording medium according to the present invention. When a bias voltage is applied between them and syn-type isomerization light 6 consisting of light such as ultraviolet rays and visible light that can supply the energy necessary for photoisomerization is irradiated according to a certain pattern, the syn-type of formula (I) is irradiated at the irradiated site. As shown in the anti-type, a photoisomerization reaction in the hv' direction occurs, rearrangement to a syn-type chelate ligand molecule occurs, and the metal ion 3 is taken up. In this way, a recording medium on which information is recorded can be obtained.

Next, as shown in FIG. 2, a monitor light 10 is applied to the recording medium.
The recorded data can be reproduced by irradiating it with light and reading the change in absorption of light from the transmitted light 9.9'.

Furthermore, after reproducing the recording, if necessary, apply a reverse voltage as shown in FIG. 3 and irradiate the anti-isomer light 11.
As shown in the above formula (I), a photoisomerization reaction in the direction of hν occurs, and rearrangement of the anti-type chelate ligand molecule occurs,
Metal ions are released and the record can be erased.

As explained above, the recorded information is read by irradiating light.

That is, since the absorption wavelength of the chelate complex and the absorption wavelength of the chelate ligand molecule are different, information is reproduced by reading changes in the absorption spectrum. Since the difference in absorption wavelength is very large, the S/N ratio when reproducing information is excellent.

Since this photoisomerization reaction can be reversibly controlled by light irradiation, metal ions can be desorbed as desired.

That is, it is possible to use the recording and reproduction repeatedly.

Furthermore, since the film has high density and high orderliness, it has excellent resolution.

[Example] EXAMPLES The present invention will be explained in more detail by showing examples below.

As the compound represented by formula 1-LLLI, those shown in Table 2 were used.

Example 1 Derivation of an imine of formula W as a chelating ligand molecule The body was dissolved in chloroform at a concentration of 5 x 10-''H and then developed on an aqueous phase of pH 5°2 and silver nitrate of 4 x 1041'l. After removing the solvent chloroform by evaporation, 31
The surface pressure is increased to 30 dyne/am while irradiating with 3 nm light.
The chelate ligand was deposited in the form of a film. After this, while keeping the surface pressure constant, the glass substrate on which ITO was deposited, whose surface was sufficiently clean and hydrophilic, was moved up and down at a speed of 3.
Gently move it up and down in the direction across the water surface at 5 cm/win to transfer the chelate ligand molecular film onto the substrate and accumulate it into a chelate ligand monomolecular film and 5, 11, 15, 21, 25 layers, Furthermore, an optical recording medium having a chelate ligand molecule film in which 11 layers of araxic acid were accumulated as a recording layer was manufactured in a similar manner. During this cumulative process, each time the substrate was lifted from the aqueous phase, it was left for 30 minutes or more to evaporate and remove the water adhering to the substrate. The film forming equipment used is JOY in the UK.
A Langmuir-Trough manufactured by CE was used. The optical recording medium was lifted from the liquid phase and dried, and a bias voltage (5 V to 10 V) was applied between two electrodes sandwiching a chelate ligand molecule film between a glass substrate coated with ITO, and 45 V was applied according to the pattern.
By irradiating with 0 nm light, an anti-sine isomerization reaction was carried out, and high-density recording of information on the order of 0 molecules was possible. Reproduction of recording was performed by reading the change in absorption at 530 nm. Next, set the reverse voltage to 5V~
When the light was applied within the IOV range and 313 nm light was irradiated for 3 minutes, thin-anti isomerization occurred and the record was erased. Furthermore, the recording-reproducing-erasing operation was repeated 35 times, and it was confirmed that repeated use was possible. Sl
No decrease in N ratio was observed.

Examples 2 to 11 Compounds of formulas U to U as chelating ligand molecules were each dissolved in chloroform at a concentration of 5 x 10'H and then placed on an aqueous phase with a concentration of cupricin, silver nitrate or molybdenum thioglycolate at a concentration of 4 x 104 M. Expanded. After removing the solvent chloroform by evaporation, 300 nm to 500 nm
The surface pressure was increased for 30dy while irradiating light with an appropriate wavelength between
ne/cm to deposit chelate ligand molecules in the form of a film.

After this, while keeping the surface pressure constant, the glass substrate with sufficiently clean and hydrophilic ITO vapor-deposited surface was gently moved up and down in the direction across the water surface at a vertical speed of 3.5 cm/win, and the chelate coordination was carried out. Transfer the molecular film onto a substrate and form a monomolecular film of chelate ligand molecules.5, 11.15.21.
Accumulate 25 layers, and add 1 layer of araxic acid in the same way.
An optical recording medium having a recording layer composed of one layer of accumulated chelate ligand molecular film was manufactured. During this cumulative process, each time the substrate was lifted from the aqueous phase, it was left for 30 minutes or more to evaporate and remove the water adhering to the substrate. The film forming equipment used is Lang++uir-Troug manufactured by JOYCiE in the UK.
The optical recording medium prepared using h (Langmuir trough) was lifted from the liquid phase, dried, and a bias voltage of 5 was applied between the two electrodes, in which a chelate ligand molecule film was sandwiched between glass substrates on which ITO was deposited. Apply within the range of V -10V and follow the pattern from 400nm to 850
By irradiating with nanometer light, an anti-sine isomerization reaction was performed and information was recorded at a high density on the order of 0 molecules. Reproduction of recording was performed by reading the absorption change at an appropriate wavelength of 450 to 700 nm.Next, a reverse voltage was applied within the range of 5 V to IOV, and 300 nm was applied.
When light of an appropriate wavelength of nm to 500 nm was irradiated for 3 minutes, thin-anti isomerization occurred and the record was erased.

Furthermore, the recording-reproducing-erasing operation was repeated 25 to 40 times, and it was confirmed that repeated use was possible. No decrease in S/N ratio was observed.

[Effect of the invention] The effects of the present invention are listed below.

1. Since a monomolecular film or a monomolecular cumulative film having high density and high orderliness can be easily produced using the Langmuir-Prodgett method, high-density recording with an excellent S/N ratio is possible.

2. The isomerization of the chelate ligand molecules is almost quantitative, resulting in excellent recording stability.

3. Since a chelate ligand molecule is used that causes efficient syn-anti isomerization and anti-syn isomerization reactions, repeated use is possible.

4. Since it uses a reversible isomerization reaction, it can be applied as a recording medium with both negative and positive functions.

5. Since it can be produced in a solid state, there is no need to assemble a solution cell.

B. It has excellent recording retention power because metal ions and the like are not desorbed unless a voltage is applied.

[Brief explanation of drawings]

1 to 3 are longitudinal sectional views showing one embodiment of a recording medium according to the present invention, respectively, in which FIG. 1 shows a recording process, FIG. 2 shows a reproduction process, and FIG. 3 shows an erasing process. Figure 4(a), (
b) is an explanatory diagram showing an example of a conventional production device. l... Thin-type chelate ligand molecule 2... Anti-type chelate ligand molecule 3... Metal ion (or metal atom) 4... Fatty acid 5... Glass substrate 6... Thin-type Isomerization light 7... ITO (transparent electrode) 8... Power supply (DC) 9.9'... Transmitted light 10... Monitor light 11... Anti-isomerization light 12... Water tank 13 ... Frame 14 ... Float 15 ... Weight] 8 ... Pulley 17 ... Magnet 18 ... Counter-magnet 19 ... Suction vibe 20 ... Suction nozzle 21 ... Liquid level 22 ...Carrier 23...Carrier upper and lower arms Fig. 1 2 7 te" 1 LffLff L-L insect function) Min 3 Shini ↑ Ascension 4 Life transformation request Figure 2 11 Anti type 1! I, I life transformation source

Claims (1)

[Claims] A recording medium comprising a monomolecular film or a cumulative film thereof of a chelate ligand molecule having a C=N bond that isomerizes when exposed to light and desorbs metal ions or metal atoms, and an electrode.