JPS6163938A - Information storage device - Google Patents

Abstract

PURPOSE:To improve the reliability of recording by using an optical recording element of which at least one layer among the layer A consisting of a colorable compd., the layer B consisting of the auxochromous compd. and the light absorptive layer consisting of a light absorptive material is constituted of a monomolecular film of the constituting materials or the cumulative film thereof. CONSTITUTION:The laminated body of the layer A 2 consisting usually of the colorless or pale color colorable compd., the layer B 4 consisting of the auxochromous compd. and the light absorptive layer 3 consisting of the light absorptive material to be interposed between the layers 2 and 4 is supported and laminated via the layer 4 on a substrate 1 in order of the substrate 1, the layer 4, the layer 3 and the layer 2, to form the optical recording element. At least one layer among the layers 2-4 consists of the monomolecular film of the respective constituting materials or the cumulative film thereof and the layers except said layer are formed of a deposited film, etc. IR rays are irradiated on such laminated body to melt or sublimate the layer 3 and to perforate the layer in desired positions, by which the layers 2 and 4 are brought into contact with each other to progress coloration reaction. Information is thus recorded. The S/N ratio is thereby increased and the reliability is improved. Defects such as pinholes are decreased and the high-density recording is made possible.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an information storage device, and in particular, information storage using an optical recording element capable of highly reliable and high-density recording using a highly molecularly oriented organic thin film. It is related to storage devices.

[Background Art] Recently, optical disks have been attracting attention as a central player in office automation (OA).

The reason for this is that a single optical disc can record (or store) a large amount of documents, literature, etc. Therefore, introducing an information storage device using this optical disc will revolutionize the organization and management of documents and literature in offices. It is something that brings. In addition, the recording element for the optical disk is inexpensive;
2. Description of the Related Art Elements made of organic materials that have features such as ease of manufacture and high-density recording are attracting attention.

Among the conventional techniques using such organic recording materials, a two-component optical recording element that utilizes a color reaction caused by contact between a color former and an auxiliary has been reported (Nikkei Sangyo Shimbun, 1972).
(October 18, 2016).

An example of a recording process by an information storage device using the conventional optical recording element will be explained based on the drawing.The optical recording element has a coloring agent layer 7 and an auxiliary coloring agent layer as shown in FIG. 2(a). 5 are laminated on the substrate 1 with a light absorption layer 6 separating them.

The coloring agent (leuco compound) and auxiliary colorant are colorless or light-colored when each exists alone.

When recording on the optical recording element, when a laser beam 8 is irradiated onto a desired position of the light absorption layer 6 as shown in FIG. 2(b), the portion of the light absorption layer irradiated with the laser beam is It absorbs light, melts, and tears, leaving small holes.

As a result, as shown in FIG. 2(c), the color forming agent and the auxiliary color agent, which were separated by the light absorbing layer 6, mix through these small holes and develop a color. Information is recorded or stored in the form of coloring points 9, and reading is performed by scanning the recording element with another light source and detecting changes in reflectance, transmittance, etc. due to the coloring points.

[Problems to be Solved by the Invention] In the above information storage device, in order to achieve high recording density, the optical recording element has a light absorption layer 6 as thin as possible, flat, and 11q thick with no unevenness. However, in conventional optical recording elements, the light absorption layer is coated on the substrate by, for example, vacuum evaporation or spin coating, so if you try to reduce the thickness to 200 to 500A or less, pinholes may occur. These pinholes tend to occur frequently, and the two components, the color former and the auxiliary color, come into contact with each other at these pinholes and develop color, resulting in a lack of reliability. Furthermore, since the molecular distribution and orientation within the film of each layer formed by the above-mentioned conventional coating method is random, light scattering occurs within the film with light irradiation, and when viewed microscopically, each light irradiation The degree of chemical reaction that occurs differs each time. Furthermore, the above-mentioned coating method has drawbacks such as unevenness in film thickness and uneven recording quality when the substrate of an optical disk has a large area.

Therefore, as an optical recording element, it is desirable that the molecular distribution and orientation within the film be uniform, that there are no pinholes, and that the film thickness is uniform, and that the film thickness be as thin as possible to achieve high recording density and high reliability. It is requested for the purpose of

The present invention has been made in view of such demands, and an object of the present invention is to provide an information storage device using an optical recording element capable of highly reliable and high-density recording.Another object of the present invention is Another object of the present invention is to provide an information storage device using an optical recording element that is easy to manufacture and inexpensive.A further object of the present invention is to provide an information storage device using a large-area optical recording element.

[Means for Solving the Problems] and [Operation] That is, the present invention consists of a layer A consisting of a color-forming compound that is usually colorless or light-colored, and a layer B consisting of an auxochrome compound that develops a color when it comes into contact with the color-forming compound. an optical recording element consisting of a layer A, a light absorption layer made of a light absorption substance, and at least one layer among the A layer, the B layer and the light absorption layer is a monomolecular film of the constituent material or a cumulative film thereof; This optical recording element is characterized by comprising an information writing means for writing information into the optical recording element, and an information reading means for reading the information written in the optical recording element.

The present invention will be explained in detail below.

FIG. 1 is a block diagram showing an example of an information storage device according to the present invention. In FIG. 1, the information storage device of the present invention consists of a layer A consisting of a color-forming compound that is usually colorless or light-colored, a layer B consisting of an auxochrome compound that develops color when in contact with the color-forming compound, and a layer B consisting of a light-absorbing compound. an optical recording element consisting of a light absorption layer made of a chemical substance, in which at least one layer among the A layer, B layer and the light absorption layer is a monomolecular film of a constituent material or a cumulative film thereof; a control circuit 27; and an optical pickup optical device. The information writing means consists of a system, and the information reading means consists of an output circuit 28 and an optical pickup optical system.

Writing is performed as follows. The control circuit 27 controls the oscillation of the semiconductor laser 2B. Therefore, the input information is converted into an optical signal by the control circuit 27 and the semiconductor laser 2B. The optical signal 23 passes through the optical pickup optical system shown in FIG.
An image is formed on the f layer and recorded in color by the above-mentioned coloring mechanism. Reading is performed as follows.

Low-power continuous wave light emitted from the semiconductor laser 26 is used as reading light. This is because, since the output is low, color recording is not performed during reading. Alternatively, other visible light sources may be used as the reading light source.

The reading light beam is imaged on the substrate surface of the optical disk 18,
However, since the reflectance differs between the coloring point and the non-coloring point, this reflected light is applied to the light receiving surface of the photodiode 25 through the optical pickup optical system, thereby converting it into an electric signal and reproducing and reading it out.

In order to increase the contrast of the reproduced signal and improve the image quality, it is preferable to provide a reflective layer of metal such as aluminum on the substrate of the optical recording element.

The thickness of the metal reflective layer is preferably 1,000 to 2,000 A. In addition, a dielectric mirror may be used as necessary.

Furthermore, a protective layer may be provided on the surface of the outermost layer to protect the A layer, B layer, light absorption layer, etc. of the optical recording element. Materials for such a protective layer include dielectrics such as 5i02, Plastic resins, other polymerizable LB films, etc. are suitable.

The optical recording element used in the present invention usually has an A layer made of a colorless or light-colored color-forming compound, a B layer made of an auxochrome compound that develops a color when in contact with the color-forming compound, and a light-absorbing substance made of a light-absorbing substance. and an absorption layer, the A layer and the B layer.
Basically, the layers are required to use a combination of substances that develop color when brought into contact with each other and mixed. The normally colorless or light-colored color-forming compound of layer A and B that have such a relationship
Specific examples of auxochrome compounds that develop color when they come into contact with the color-forming compound of the layer are as follows: (a) An acidic substance (layer q) and a leuco compound (dye precursor) of a dye that develops a color when it comes into contact with the acidic substance. ) CA layer) (b) An oxidizing agent (layer B) and a leuco form of a dye that develops color when it comes into contact with the oxidizing agent (layer A) (c) A reducing agent (layer B) and a leuco form of the dye that develops color when it comes into contact with the reducing agent Leuco form of dye that develops color (layer A) (d) Reducing agent (layer B) and oxidizing agent (layer A) that develops color when reduced, such as ferric stearate (e) Oxidizing agent (layer B) Examples include reducing agents (layer A) that develop color when oxidized, such as gallic acid.

To give a more detailed example of the case (a) above, the acidic substances in the B layer that react with the leuco form of the dye and develop color include aromatic sulfonic acid compounds such as benzene/sulfonic acid, benzoic acid, etc. Aromatic carboxylic acids, palmitic acid CC15H3+ GOOH), stearic acid ((: t
7 HJ5 C00H), Araxic acid (C: 19
Higher fatty acid carboxylic acids such as Hiq GOOH), p-
Examples include phenolic compounds such as t-butylphenol, α-naphthol, β-naphthol, phenolphthalein, bisphenol A, 4-hydroxydiphenoxide, and 4-hydroxyacetophenone.

Next, examples of the leuco dyes in the A layer that react with the acidic substance include triphenylmethane, fluoran, phenothiazine, auramine, and spiropyran. The details of the compounds are shown in Table 1.

Next, the light-absorbing material used in the formation of the light-absorbing layer in the present invention may be any light-absorbing dye that absorbs infrared rays, such as a melting light-absorbing dye that melts by absorbing infrared rays, or Sublimable light-absorbing dyes that absorb infrared rays and sublimate, non-melting dyes, non-sublimating dyes, etc. can be used.

Examples of such light-absorbing dyes include metal phthalocyanines such as copper phthalocyanine and vanadium phthalocyanine, and xanthine dyes such as fluorescein.

One feature of the optical recording element used in the present invention is that at least one layer among the A layer, the B layer, and the light absorption layer is composed of one single molecule of each constituent material or an accumulation of 119 single molecules thereof. Therefore, when the A layer, the B layer, or the light absorption layer forms a monomolecular film or a cumulative film thereof, the above-mentioned color-forming compound, auxochrome compound, or light-absorbing substance has no exit site within the molecule. It is necessary to use a derivative in which a parent wood group, a hydrophobic group, or both groups are introduced.

Any hydrophobic group can be used, but the hydrophobic group is preferably a long-chain alkyl group having 5 to 30 carbon atoms, and the parent group is preferably a carboxyl group or a metal salt thereof (for example, a cadmium salt).

On the other hand, if the A layer, the B layer, or the light absorption layer does not form a monomolecular film or a cumulative film thereof, any film can be used as each layer as long as it is formed by a conventional coating method. Among them, a layer consisting of a deposited film such as a vapor deposited film, a coating film, a dipping film, or a laminate is preferred.

In addition, the film thickness of the A layer and the B layer is 2.
The range is preferably from 00 to 10JJ, preferably 1,
It ranges from 0008 to 1 river.

On the other hand, when a monomolecular film or a cumulative film thereof is used, the thickness of the light absorption layer is desirably in the range of 30 to 1,000 A, preferably in the range of 50 to 200 A, and When using IQ, l, ooo from 90 people
A is preferably in the range of 140 or more. Materials used for the substrate in the present invention include semiconductor materials such as silicon, metal materials such as aluminum, preferably tempered glass, and more preferably acrylic ( PMMA), polycarbonate (pc), polypropylene, polyvinyl chloride (p
VC), plastic materials such as polystyrene, and ceramic materials are preferred.

As mentioned above, in the optical recording element used in the present invention, at least one of the A layer made of a color-forming compound, the B layer made of an auxochrome compound, and the light absorption layer made of a light-absorbing substance is a monomolecular film of a constituent material. or consisting of a cumulative film thereof.
It has three characteristics.

As a method for producing a monomolecular film or a cumulative film thereof having such high orderliness and orientation of molecules, for example, 1. La
The Langmuir-Prodgett method (LB method) developed by Ngmuir et al. is used. The Langmuir-Prodgett method is based on the Langmuir-Prodgett method. For example, when a molecule has a parent tree group and a hydrophobic group in its molecule, and the balance between the two (balance of amphiphilicity) is maintained appropriately, the molecule will react to the parent tree on the water surface. This is a method of creating a monomolecular film or a monomolecular cumulative film by using the fact that the monomolecular layer is formed with the group facing downward. A monolayer on the water surface has the characteristics of a two-dimensional system. When the molecules are sparsely dispersed, the two-dimensional ideal gas equation, nA = kT, holds true between the area per molecule A and the surface pressure ■, resulting in a "gas film °°. Here, The Boltzmann constant, T, is the absolute temperature.If A is made sufficiently small, the intermolecular interaction becomes strong, resulting in a two-dimensional solid "condensed film (or solid film)." The condensed film can be transferred layer by layer onto the surface of carriers having various materials and shapes, such as plastic substrates and glass substrates.

Next, the method for forming a monomolecular film or a cumulative film thereof of an organic molecule having a parent group or a hydrophobic group, which is a color-forming compound, an auxochrome compound, or a light-absorbing substance used in the present invention, will be described in further detail. .

First, the organic molecule is dissolved in a volatile solvent such as benzene or chloroform, and this is spread on the aqueous phase 11 in the water tank 10 of the monomolecular cumulative film forming apparatus schematically shown in FIG. 3 using a cylinder or the like.

As the solvent evaporates, the organic molecules develop on the water phase 11 with the parent tree groups 12 facing the water phase and the hydrophobic groups 13 facing the gas phase.

Next, a partition plate (or float) 14 is installed to prevent this precipitate (organic molecules) from freely diffusing and spreading too much on the aqueous phase 11.
is provided to limit the developed area and control the state of aggregation of the membrane material, thereby obtaining a surface pressure (2) proportional to the state of aggregation. By moving the partition plate 14, the developed area can be reduced to control the aggregation state 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 vertically moving the clean substrate 14 up and down while maintaining this surface pressure, the monomolecular film 16 is transferred onto the substrate. The monomolecular layer 16 is manufactured as described above, and the monomolecular layer cumulative film 17 is formed by repeating the above-mentioned operations to form a desired cumulative number of monomolecular layer cumulative films.

For example, when the substrate 15 whose surface is woody is pulled out of water in a direction across the water surface, the woody groups of the organic molecules are removed from the substrate 15.
A side-facing monolayer 16 is formed on the substrate 15 . When the substrate 15 is moved up and down as described above.

The monomolecular layer 1B is stacked one by one in each process, and the direction of the film-forming molecules is reversed between the pulling process and the dipping process, so according to this method, between each layer, the parent tree base of the organic molecule and the parent base , a so-called Y-type film is formed in which the hydrophobic groups of the organic molecules face each other (FIG. 4(a)).

The Y-type film is strong because the hydrophilic groups and hydrophobic groups of the organic molecules face each other.

In contrast, only when lowering the substrate 15 into the water,
There is also a method of transferring the organic molecules onto the substrate surface.

In this method, there is no change in the direction of the film-forming molecules even if the films are accumulated, and an X-type film is formed in which the hydrophobic groups face the substrate 15 in all layers (FIG. 4(b)). On the other hand, a cumulative film in which parent wood groups in all layers face the substrate 15 side is called an X-type film (FIG. 4(C)).

The X-type film is obtained by transferring organic molecules to the substrate surface only when the substrate 15 is lifted out of the water.

The monomolecular film and monomolecular layer stack formed on the substrate by the above method have high density and a high degree of order and orientation, and by forming the recording layer with these films, A recording element capable of photothermal recording and having a high-density, high-resolution recording function can be obtained. Further, as can be seen from the principles thereof, these film forming methods are very simple methods, and a recording element having the above-mentioned excellent recording function can be provided at low cost.

The substrate on which the monomolecular film or monomolecular cumulative film in the present invention is formed as described above is not particularly limited, but if a surfactant is attached to the surface of the substrate, when the monomolecular layer is transferred from the water surface, the monomolecular Since the film is disturbed and a good monomolecular film or monomolecular layer stack cannot be formed, it is necessary to use a substrate with a clean surface.

The monomolecular film or monomolecular layer accumulation film on the substrate is sufficiently strongly fixed and rarely peels or peels off from the substrate. An adhesive layer can also be provided between the layer stacks. Furthermore, the adhesion force can be strengthened by selecting the monomolecular layer formation conditions, such as the hydrogen ion concentration of the aqueous phase, the ion species, the water temperature, the rate of raising and lowering the carrier, or the surface pressure.

Next, the method for forming the deposited film of layer A, layer B, or light absorption layer is to use a ball mill or the like to prepare a water mixture in which a binder and water are added to the color-forming compound, auxochrome compound, or light-absorbing substance. After pulverizing and mixing, it is applied onto a substrate or the like using a conventional method.

The binder used in the present invention includes gelatin,
Natural polymers such as starch, cellulose nitrate, cellulose derivatives such as carboxymethyl cellulose, chlorinated rubber,
Semi-synthetic polymers such as natural rubber plastics such as cyclized rubber, polyisobutylene, polystyrene, terpene resins,
Polyacrylic acid, polyacrylic ugly ester, polymethacrylic ester, polyacrylonitrile, polyacrylamide, polyvinyl acetate, polyvinyl alcohol, polyvinylpyrrolidone, polyacetal resin, polyvinyl chloride, polyvinylpyridine, polyvinylcarbazole,
Polymerizable synthetic polymers such as polybutadiene, polystyrene-butadiene, butyl rubber, polyoxymethylene, polyethyleneimine, polyethyleneimine hydrochloride, poly(2-acryloxyethyldimethylsulfonium chloride), phenolic resins, amine resins, toluene resins, alkyds Condensation polymerization type synthetic polymers such as resins, unsaturated polyester resins, allyl resins, polycarbonates, polyamide resins, polyether resins, silicone resins, furan resins, thiol rubber, etc., addition polymerization such as polyurethanes, polyureas, epoxy resins, etc. Examples include mold resin.

As a method for forming the reflective layer in the present invention, conventional methods that have been conventionally used can be used, and among these, vacuum evaporation, sputtering, etc. are preferable.

In addition, the method for forming the protective layer in the present invention can be any conventionally practiced method, including, for example, a plasma GVD method, a photo CVD method, a vacuum evaporation method, a sputtering method, a coating method, etc. preferable.

A structure in which the method of forming each layer described above is used as the intended purpose,
The optical recording element according to the present invention can be easily manufactured by sequentially combining the components according to the configuration.

Next, embodiments of the structure of the optical recording element used in the present invention will be shown below.

(I) FIG. 5(a) shows an example of an embodiment. 1 A layer 2 made of a color-forming compound, 3 layers 4 made of an auxochrome compound, and a light absorbing layer interposed between the A layer and the B layer. A laminate consisting of a light absorption layer 3 made of a substance is supported on a substrate 1 via the B layer 4, and laminated in the order of substrate/B layer/light absorption layer/A layer.

Furthermore, as another example, the A layer of the laminate may be supported on a substrate, and the layers may be laminated in the order of substrate/A layer/light absorption layer/B layer,
Alternatively, two of the laminates may be stacked on top of each other, and the lowest layer A or B may be supported on the substrate.

In the above structure, at least one of the A layer, B layer, and light absorption layer of the M layer body is made of a monomolecular film of each constituent material or a cumulative film thereof, and the other layers are formed of deposited films or the like. .

Specific examples thereof are as follows.

(1) The A layer, the B layer, and the light absorption layer are all monomolecular films or their cumulative films (hereinafter referred to as "rLB film"). (2) The A layer, the light absorption layer are LB films, and the B layer is a deposited film (rLB film). 3) Light absorption layer, B layer is LB
Film, A layer is a deposited film (4) A layer and B layer are LB film, light absorption layer is a deposited film (5) A layer is LB film, B layer, light absorption layer is a deposited film (6) Light absorption layer is a deposited film LB film, A layer, and B layer are deposited films (7) B
The layer is LB151. A layer and light absorption layer are deposited films (I) above.
The optical recording element used in the present invention has a structure in which the A layer and the B layer are separated by a light absorbing layer, so the light absorbing layer is melted or sublimated by infrared irradiation to form holes at desired positions. By opening the area, the color-forming compound of layer A and the auxochrome compound of layer B come into contact and a color-forming reaction proceeds, forming a color-forming point at the position and recording information.

(II) FIG. 5(b) shows a laminated layer formed by laminating an A layer 2 made of a color-forming compound and eight layers 4 made of an auxochrome compound, and further providing a light absorption layer 3 on top of the B layer 4. The light absorbing layer 3 is supported on the substrate 1 through the light absorbing layer 3, and the layers are laminated in the order of substrate/light absorbing layer/B layer/A layer. In this case A layer 2
and 8 layers 4 may be reversed and laminated in the order of substrate/light absorption layer/layer A/layer B.

Furthermore, to show another example, as shown in FIG. 5(C),
Layers 2 and 8 layers 4 are laminated, a light absorption layer 3 is provided roughly on the A layer 2 to form a laminate, the 8 layers 4 are supported on a substrate l, and the substrate/B layer/A It is formed by laminating layers/light absorption layer in this order. In this case, similarly to the above, the A layer 2 and the 8-layer 4 may be reversed and laminated in the order of substrate/A layer/B layer/light absorption layer.

Moreover, in any of the configurations shown in FIGS. 5(b) and 5(c) above, two of the above-mentioned laminates are installed! ! They may be supported on the substrate in a stacked manner.

In the configuration (II) above, the A layer and B layer of the 81-layer body
At least one of the layers and the light absorption layer is formed of a monomolecular film of each constituent material or a cumulative film thereof, and the other layers are formed of deposited films.

Specific examples thereof include (1) to (1) of the embodiment (1) above.
As stated in 7).

The optical recording element having the structure (II) above is constructed by closely adhering the A layer made of a color-forming compound and the B layer made of an auxochrome compound, but this is not possible with conventional technology. It was considered impossible. However, in the present invention, since the A layer and/or the B layer is formed of a monomolecular film having a high degree of order and orientation of molecules and a cumulative film thereof, The above configuration was made possible because the reactive sites could be separated from each other.

Furthermore, since the optical recording element used in the present invention having the structure (I[) above is constructed by laminating layer A and layer B in close contact with each other and further providing a light absorption layer on the outside, it is possible to irradiate it with infrared rays. The light absorption layer is heated by the heat conduction, and A
The color-forming compound of the layer and the auxochrome compound of the layer B come into contact with each other under heat, a color-forming reaction progresses, and a color-forming point is formed at a predetermined position so that information can be recorded. In this case, non-melting dyes and non-sublimating dyes are suitable as the light-absorbing substance.

[Example] Hereinafter, the present invention will be explained in more detail by showing examples. In the following, unless otherwise specified, "part" means "part by weight" and "r%" means "% by weight."

Synthesis Example 1 (Synthesis Example of Light Absorbing Substance) After mixing and dissolving 10 parts of vanadium phthalocyanine urea and 1 part of a 10-15% phosphoric acid aqueous solution, 2 parts of phthalic anhydride and 700 mon 2 (vanadyl salt) 10 70 parts and 8 parts of a derivative of phthalic anhydride represented by formula (1) O, 10
Heated at 0°C for 5 hours. After cooling, 2% dilute NaOH
After adding 100 parts of an aqueous solution and hydrolyzing, it was separated by chromatography to obtain the formula (II) [In the formula (■), R is T C-0-C, H9 star 0H ((H2), OH.

0.1 part of a target substance (vanadium phthalocyanine derivative) represented by the following formula was obtained.

Synthesis example 2 (synthesis example of color-forming compound) Synthesis of crystal violet Trafton J lead (II
I) 1 part of m-aminobenzoic acid derivative represented by formula (IV
) Mix 1 part of Michler's hydrol, represented by CH , in O
The mixture was refluxed for 8 hours to produce a triphenylmethane derivative represented by the formula (V) (CH2), 7C13.

Next, the triphenylmethane derivative of the product was converted into lead dioxide (
1 part) After heating in sulfuric acid for 3 hours in the presence of formula (Vl) (OH2), CH.

A crystal violet lactone derivative represented by was obtained.

Next, by adding an aqueous solution of caustic soda to this and cyclizing it, a crystal violet lactone derivative represented by the formula (■) (CH2), 7CH3 0.
Got 2 copies.

Example 1 (1) Method for Forming Layer B A glass (disk) substrate on a disk of 10 mm thick and 180 mm diameter was thoroughly cleaned, and 7 parts of araxic acid, which is a zero-order auxochrome compound, and a binder were prepared. 1 part of polyvinyl alcohol and 40 parts of water were mixed together using a ball mill for several hours, and the mixture was spin-coated onto a substrate to form a deposited film (film thickness II) of alaxic acid dispersed in the binder.
Each sample forming L) was obtained.

(2) Method for forming a light-absorbing layer Next, the light-absorbing material vanadium was added to the B layer formed on the glass substrate of each sample obtained in (1) above using the monomolecule accumulator described above. A monomolecular cumulative film of phthalocyanine derivatives was formed.

A monomolecular cumulative film of a vanadium phthalocyanine derivative was formed as follows.

After submerging the substrate in water so that the substrate on which layer B was formed is perpendicular to the water surface, a solution of vanadium phthalocyanine derivative in chloroform with a concentration of 2 × 10' mol/jl was dropped onto the water surface to form a monomolecular film. 0 unfolding on the water surface
Set surface pressure to 30dyne/c+s, speed 2cm
A monomolecular cumulative film (Y-type film) was prepared for each sample by moving the substrate up and down with /win to form a monomolecular cumulative film (Y-type film) in each layer shown in Table 2.

- (3) Method for Forming Layer A Next, a deposited film of crystal bioleft lactone, which is a color-forming compound, was formed on the light absorption layer formed on the glass substrate of each sample in (2) above.

The formation method is to mix 7 parts of crystal violet lactone, 1 part of polyvinyl alcohol as a binder, and 100 parts of water, then grind and mix for several hours using a ball mill, and then spin-coat it on the light absorption layer of the substrate and disperse it in the binder. Deposited film of crystal violet lactone (film thickness l)
) was obtained.

(4) Performance test The optical recording element used in the present invention manufactured by the above-mentioned method and a conventional optical disc having a similar structure (all constructed without using a monomolecular film or a cumulative film thereof) were used as a comparative example. After recording under the following recording conditions using the information storage device according to the present invention shown in FIG. 1, performance was compared between the two by reading and reproducing.

<Recording conditions> Semiconductor laser wavelength: 830 nm Laser output: 6-9II1111 Recording frequency: 5 MHz Optical disk rotation speed: Reading was performed with a laser output of 1 mW under conditions of 1.80 Orpm or more, and the signal/noise ratio was determined. Table 2 shows the results of the signal/noise ratio. show.

From the results in Table 2, when comparing No. 1 (when the light absorption layer is made of a monomolecular film) and No. 006, it is recognized that No. 1 is significantly superior in signal/noise ratio. The reason for the difference in performance between No. 1 and No. 8, even though the thickness of each layer was almost the same, is probably because No. 1 had fewer defects such as pinholes.

Similarly, in the comparison between No. 92 to No. 5 (when the light absorption layer consists of a cumulative film of Cli molecules) and No. 7, No.
It is recognized that Nos. 02 to 5 are superior in signal/noise ratio.

[Effects of the Invention] As explained above, in the information storage device according to the present invention, at least one layer among the A layer, the B layer, and the light absorption layer is composed of a monomolecular film of a constituent material or a layer consisting of a cumulative film thereof. Since the optical recording element is used, there are excellent effects as shown below.

(1) Conventional monomolecular film or its accumulation vIIl! The signal/noise ratio is higher than that of an optical recording element that does not use 2, and recording reliability can be improved.

(2) Physical defects such as pinholes in optical recording elements can be significantly reduced.

(3) Higher density recording is possible than with conventional optical recording elements.

(4) It is possible to increase the area of the optical recording element.

(5) When the light absorption layer is not interposed between the A layer and the B layer, color development efficiency and fidelity are improved.

(6) By adopting a configuration in which the light absorption layer is not interposed between the A layer and the B layer, the recording layer can be made thinner, and higher density recording is possible.

(7) Materials that have good coloring efficiency and are excellent as coloring agents, etc., but are difficult to form a monomolecular film or a cumulative film thereof: 1, or chemically changed to a derivative that easily forms a monomolecular film or a cumulative film thereof. There is an advantage that materials that are difficult to (synthesize) due to cost can be used for the deposited film.

(8) Since a deposited film is used in a part of the laminate, sensitivity is improved, there is a wide range of material selection during manufacturing, and manufacturing is easy, and the difference between contrast and non-contrast during reading is improved. It has effects on optical properties such as easy adhesion.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an example of an information storage device according to the present invention, FIGS. 2(a) to 2(C) are explanatory diagrams showing the recording process of a conventional optical recording element, and FIG. single molecule cumulative n
Schematic cross-sectional view of the Q forming device, FIGS. 4(a) to 4(a)
C) is a manufacturing process diagram of a monomolecular cumulative film, and FIGS. 5(a) to 5(c) are schematic cross-sectional views showing embodiments of the optical recording element used in the information storage device of the present invention. .

Claims (1)

[Claims] (1) Consisting of a layer A consisting of a color-forming compound that is usually colorless or light-colored, a layer B consisting of an auxochrome compound that develops color when in contact with the color-forming compound, and a light-absorbing layer consisting of a light-absorbing substance, and an optical recording element in which at least one of the A layer, the B layer, and the light absorption layer is composed of a monomolecular film of a constituent material or a cumulative film thereof, an information writing means for writing information in the optical recording element, and the optical recording element. An information storage device comprising: information reading means for reading information written in an element.