JP2003089269A - Organic thin film, method for manufacturing organic thin film, optical recording medium using the film, and method for regenerating records of optical recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide (1) a new organic thin film, in which a functional coloring matter dispersion structure of a nanometer size and a cocontinuous shape such as spherical, columnar or lamellar is constituted in an organic polymer, with the expected use applications of the organic thin film for an electronic and an optical material, and a method for manufacturing the organic thin film, and (2) an optical recording medium capable of regenerating records at a recording density beyond the diffraction limits of a pickup lens, compared to a conventional optical disc which cannot achieve such a recording density, and a record regeneration method. SOLUTION: (1) This organic thin film is characterized in that it is of a microphase separation structure, composed mainly of a block copolymer consisting of at least two kinds of mutually non-compatible polymer blocks, and only one of the phases of the microphase separation structure contains a functional coloring matter. (2) The microphase separation structure of the organic thin film is of a cocontinuous shape such as spherical, columnar or lamellar or a similar shape thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic thin film applicable to electronic materials, optical materials and the like, a method for producing the same, and an ultra high density optical recording medium (optical disk, optical disk, etc.) using the organic thin film.
Optical card, optical tape, etc.) and its recording and reproducing method.

[0002]

2. Description of the Related Art Introducing a nanometer-sized functional material into a polymer to form a composite is a functional composite that exhibits new functions such as electronic properties, conductive properties, optical properties, and magnetic properties. This is an important technique for obtaining materials. Conventionally, research and development of metal-organic composite materials using ultrafine metal particles (metal nanoclusters) as functional materials have been advanced. However, at present, research and development of composite materials of nanometer-sized functional organic materials and polymers, which can be expected to have infinite degree of freedom and functionality, have not been advanced at present.

On the other hand, in the optical memory field, CD-R and DVD-R, which are optical recording media having a reflective layer on a substrate and capable of recording in accordance with the CD standard and the DVD standard, have been commercialized. In the future, further improvement of recording capacity and miniaturization of these optical recording media are desired, and further improvement of recording density is required to realize this. As an elemental technology for improving the recording capacity of the current system,
There are recording pit miniaturization technology and image compression technology typified by MPEG2. In the technology of miniaturizing recording pits, it is considered to increase the numerical aperture NA of the optical system in order to shorten the wavelength of recording / reproducing light and improve the diffraction limit, but recording / reproducing exceeding the diffraction limit is not possible. It is possible. Therefore, a super-resolution technique capable of recording and reproducing exceeding the diffraction limit and an optical memory system using near-field light have been attracting attention as a promising means, but due to the technical hurdle, they have not yet been put to practical use.

Further, the recording layer (layer in which the recording material is present) of the conventional optical recording medium is usually a continuous layer,
The layer is irradiated with a laser beam, and the recording material is recorded by causing some change corresponding to the shape of the laser beam. Therefore, the size of the minimum recording pit depends on the laser beam diameter determined by the oscillation wavelength and the numerical aperture NA of the lens. Therefore, in the conventional recording / reproducing system, high density is basically required for the laser oscillation wavelength and the lens. It has been influenced by the practical application technology of NA. In addition, since the beam shape is a Gaussian distribution and there is almost no material that changes with a clear threshold value for heat or light as a recording material, the size and amount of change in the outermost circumference of the formed pit are However, the reproduction signal quality is not always uniform, and there is always a variation factor in the reproduction signal quality, and there is a limit in obtaining high-quality signal characteristics.

[0005]

DISCLOSURE OF THE INVENTION The present invention provides (1) a nanometer-sized co-continuous shape such as spherical, columnar, or lamellar shape, which is expected to be applied as an electronic material or an optical material, or a structure similar to them. Providing a novel organic thin film in which a functional dye dispersion structure is constructed in an organic polymer and a method for producing the same, and (2) recording at a recording density exceeding the diffraction limit of a pickup lens, which cannot be realized by a conventional optical disc. An object is to provide a reproducible ultra-high density optical recording medium and a recording / reproducing method thereof.

[0006]

Means for Solving the Problems As a result of intensive studies, the inventors of the present invention used a microphase separation phenomenon of a polymer to allow a dye to be contained in only one of the phase-separated phases. We have succeeded in obtaining an organic thin film as a functional composite material that exhibits a new function such as electronic properties, conductive properties, and optical properties by introducing a functional dye into a polymer to form a composite. Further, unlike the conventional approach from the light source side, by using the organic thin film as an optical recording medium, it is possible to obtain a recording medium in which the area of the recording medium itself is smaller than the diffraction limit of irradiation light into a dot array. And succeeded in obtaining an ultra-high density optical recording medium capable of recording / reproducing at a recording density exceeding the diffraction limit of a laser pickup, which could not be achieved by the conventional technique.

That is, the above problems are solved by the following inventions 1) to 12) (hereinafter referred to as the inventions 1 to 12). 1) A main component is a block copolymer composed of two or more kinds of polymer blocks which are incompatible with each other, has a micro phase separation structure, and a functional dye is contained in only one phase of the micro phase separation structure. An organic thin film characterized by being present. 2) The organic thin film according to 1), wherein the microphase-separated structure is a co-continuous structure such as spherical, columnar, or lamellar, or a structure similar thereto. 3) The functional dye comprises a dye having a function of changing its optical characteristics by light or heat 1)
Or the organic thin film described in 2). 4) A solution containing a block copolymer composed of two or more kinds of polymer blocks incompatible with each other and a functional dye having compatibility with only one phase of a microphase-separated structure is prepared, and then the solution is prepared. The method for producing an organic thin film according to any one of 1) to 3), wherein the microphase-separated structure is formed by solvent casting or temperature change after forming the thin film from 5) A solution containing a block copolymer composed of two or more kinds of polymer blocks incompatible with each other is prepared, and then a thin film is formed from the solution, followed by solvent casting or temperature change to form a microphase-separated structure. Then, the method for producing an organic thin film according to any one of 1) to 3), which is characterized by subsequently bringing into contact with a solution containing a functional dye that is compatible with only one phase of the microphase-separated structure. 6) A solution containing a block copolymer composed of two or more polymer blocks incompatible with each other is prepared, and then a thin film is formed from the solution, followed by solvent casting or temperature change to form a microphase-separated structure. Any one of 1) to 3) above, further comprising laminating a functional dye having compatibility with only one phase of the microphase-separated structure, and then diffusing the functional dye by heating. A method for producing an organic thin film as described in 1. 7) An optical recording medium comprising the organic thin film according to any one of 1) to 3) as a recording layer material. 8) The optical recording medium according to 7), which contains a functional dye whose wavelength is controlled to have a maximum absorption wavelength in the vicinity of the wavelength of the recording / reproducing laser beam. 9) The optical recording medium according to 7), which contains a functional dye whose wavelength is controlled to have a maximum refractive index in the vicinity of the wavelength of the recording / reproducing laser beam. 10) The optical recording medium according to any one of 7) to 9), wherein the functional dye is a photochromic dye. 11) The light according to any one of 7) to 10), wherein the recording / reproducing is performed by changing the optical characteristics of one phase of the microphase-separated structure containing the functional dye by irradiation with laser light. Recording medium reproducing method. 12) Optical characteristics are fluorescent characteristics 1
1) The recording / reproducing method of the optical recording medium described in

The present invention will be described in detail below. The organic thin film of the present invention comprises a block copolymer composed of two or more kinds of polymer blocks which are incompatible with each other as a main component, has a micro phase separation structure, and is functional only in one phase of the micro phase separation structure. It contains a pigment.
The characteristic of this organic thin film is that the functional dye is present in the polymer matrix in a nanometer size and highly ordered. The microphase separation phenomenon of the block copolymer is used as the driving force. The microphase-separated structure is preferably spherical, columnar, co-continuous such as lamella, or a structure similar thereto, and as the functional dye,
A dye having a function of changing its optical characteristics by light or heat is preferable. 1 (a) to 1 (c), spherical, columnar,
An example in which a functional pigment is contained in the lamellar structure is shown. (C) shows an example of an alternating lamella structure in which a functional pigment is contained in one lamella.
As described above, a nanometer-sized functional dye is introduced into a polymer, and three-dimensionally highly structurally controlled to form a composite, thereby providing new properties such as electronic properties, conductive properties, and optical properties. An organic thin film exhibiting a function is obtained.

Next, a method of manufacturing the above organic thin film will be described. It is known prior to the present application that a block copolymer composed of two or more polymer blocks incompatible with each other forms a microphase-separated structure by solvent casting or temperature change, but the organic thin film of the present invention is It is manufactured by the following method using a known phenomenon. That is, the first method is to prepare a solution containing a block copolymer composed of two or more kinds of polymer blocks that are incompatible with each other and a functional dye that is compatible only with one phase of the microphase-separated structure. Then
Then, a method of forming a microphase-separated structure by solvent casting or temperature change after forming a thin film by a dip coating method, a spin coating method, or the like. The second method is to prepare a solution containing a block copolymer composed of two or more polymer blocks which are incompatible with each other, and then form a microphase-separated structure in the same manner as in the first production method. A method of contacting by immersing in a solution containing a functional dye that is compatible with only one phase of the microphase-separated structure, or coating the solution with the solution. The third method is to prepare a solution containing a block copolymer composed of two or more polymer blocks incompatible with each other, and then form a microphase-separated structure in the same manner as in the first production method, On top of that,
This is a method in which a functional dye having compatibility with only one phase of the microphase-separated structure is laminated by spin coating or a vacuum deposition method, and then the organic thin film is heated to diffuse the functional dye. In addition, in order to promote microphase separation, other polymers may be added in addition to the above block copolymer composed of two or more kinds of incompatible polymer blocks.

Next, an optical recording medium using the above organic thin film as a recording layer material will be described. The optical recording medium of the present invention has a new structure that overcomes the problems of the prior art. That is, in the optical recording medium using the organic thin film of the present invention, the recording layer dots that are highly ordered in a continuous layer exist discontinuously through the matrix, and the size of the recording layer dot is large. Are formed in a uniform nanometer size (10 to 500 nm). Therefore, the size of the minimum recording pit depends on the laser oscillation wavelength and the NA of the lens.
It is determined only by the recording layer dots to be formed without being determined by, and a recording medium having an arbitrary recording density can be designed. Further, in the conventional optical disc, the recording layer is formed of a uniform film, so that when it is irradiated with a laser, a light absorption distribution and a heat-converted heat distribution are formed on the recording layer. It Then, a reaction occurs in a portion of the photon mode and the heat mode which is equal to or more than the threshold value, and a pit is formed. However, in a normal reaction, the threshold value is not so clear and the boundaries of the pits are varied, that is, the pit shapes are varied, which causes a data error. On the other hand, in the structure of the present invention, the portion that absorbs light is isolated (one layer of micro phase separation), and the size of the micro structure is a pit shape. It does not change. That is, since the outermost edge of the pit is also determined by the structure of the organic thin film, it is possible to obtain high-quality signal characteristics without variations in the pits by recording by changing the entire recording layer dots. It will be possible.

Next, the layer structure of the optical recording medium and the required physical properties of each layer will be described. << Layer structure of recording medium >> The layer structure of the optical recording medium of the present invention may be a structure of a write-once optical disc (a so-called air sandwich structure in which two substrates each having a recording layer provided on a substrate are bonded together). -R structure (recording layer on substrate,
A structure having a reflective layer and a protective layer), and a CD-R
A DVD structure in which the structures are attached may be used. 2 (a)-
An example of a typical layer structure is shown in (c). In the figure, 1 is a substrate,
2 is a recording layer and 3 is a reflective layer.

<Substrate> The substrate to be used must be transparent to the laser used only when recording and reproducing from the substrate side, and the substrate is transparent when recording and reproducing from the recording layer side. It doesn't have to be. As the substrate material, for example, polyester, acrylic resin, polyamide, polycarbonate, polyolefin, phenol resin, epoxy resin, plastic such as polyimide, or glass, ceramic, metal, or the like can be used. In addition, a guide groove for tracking, a guide pit, a preformat such as an address signal, etc. may be formed on the surface of the substrate.

<Recording Layer> The recording layer is a layer capable of recording / reproducing information due to some kind of optical change caused by irradiation of laser light, and a block composed of two or more kinds of polymer blocks incompatible with each other. It has a structure in which a polymer is a main component, and a functional dye (optical recording dye) is contained in only one phase of the microphase-separated structure. There are various optical characteristics that functional dyes (optical recording dyes) should retain, but when reproducing by utilizing the change in absorption characteristics (change in transmittance) with respect to the laser wavelength for recording / reproduction, near the laser wavelength. It is preferable to control the wavelength so that it has the maximum absorption wavelength, and when reproducing by utilizing the change in the refractive index of the recording / reproducing laser wavelength, the wavelength control is performed so that the maximum refractive index is near the laser wavelength. Preferably. Also, laser light irradiation changes the fluorescent properties of the dye,
In the case of the method of reproducing by utilizing the change, compared with the case of utilizing the change of the transmittance or the change of the refractive index, the S / N ratio is large and the reproduction with high contrast is possible even with a slight change, When the size of the recording pit as in the optical recording medium of the present invention is determined from the beginning, recording is possible at a significantly lower energy as compared with the conventional method, which is particularly preferable. In the conventional method, it was necessary to form a clear pit shape by recording, and recording could not be performed unless the reaction rate of the recording layer material due to laser light irradiation was high. On the other hand, in the optical recording medium of the present invention in which pits are already formed, reproduction is possible even with a small reaction rate, and fluorescence reproduction is particularly effective.

The block copolymer according to the present invention is synthesized by combining two or more types of monomers which form incompatible polymer blocks. As the synthetic method, styrene, isoprene, α-methylstyrene, chloromethylstyrene, 2-vinylpyridine, aminostyrene, 4-
Living polymerization method (anion polymerization, living radical polymerization) in which monomers such as vinyl pyridine, methacrylates, ε-caprolactone, butadiene, vinyl methyl ether, 1,3-cyclohexanediene and ethylene oxide are polymerized from the end of the chain, and chain The living polymerization (anionic polymerization) synthesized from the center of the polymer and the synthetic method (anionic polymerization, living radical polymerization) of connecting the ends of the terminal functional polymer are adopted. Examples of three or more polymer blocks include polystyrene-polybutadiene-polymethylmethacrylate, polystyrene-partially hydrogenated polybutadiene-polymethylmethacrylate,
Examples thereof include polyvinyl pyridine-polystyrene-polybutyl methacrylate, polyisoprene-polystyrene-polyvinyl methyl ether and the like. However, in order to have a function as the organic thin film of the present invention, for example, a combination of three kinds of polymers in which two kinds of polymers are compatible with each other and another kind of polymer is incompatible, substantially, It must be a combination that can form the two-phase separated state shown in FIG.

Examples of the recording dye include polymethine dyes whose optical constants are changed in a heat mode (pyrolysis, etc.) by irradiation energy of laser light, squarylium dyes, pyrylium dyes, porphyrin dyes, porphyrazine dyes, azo dyes, Azomethine dyes, and their metal complex compounds, and fulgides, diarylethenes, azobenzenes, spiropyrans, stilbenes, dihydropyrenes, thioindigos, bipyridines whose optical constants are changed in the photon mode by irradiation energy of laser light. And aziridines, aromatic polycycles, allylidene anilines, xanthenes and the like, and rewritable photochromic materials are particularly preferable. The above dyes may be used alone or in combination of two or more. Further, a stabilizer (for example, a transition metal complex), an ultraviolet absorber, a dispersant, a flame retardant, a lubricant, an antistatic agent, a surfactant, a plasticizer, etc. may be added to the above dye for the purpose of improving the characteristics. it can. The dot diameter of the functional dye (optical recording dye) is 5 nm to 500 nm,
It is preferably 10 nm to 200 nm.

<< Undercoat Layer >> The undercoat layer comprises a) improved adhesion, b) barrier against water and gas, c) improved storage stability of the recording layer, d) improved reflectance, and e) solvent. It is used for the purpose of protecting the substrate from heat, f) forming guide grooves, guide pits, and preformats. For the purpose of a), ionomer resin, polyamide resin, vinyl resin,
Various polymer compounds such as natural resins, natural polymers, silicones, liquid rubbers, and polymer materials such as silane coupling agents can be used. For the purposes of b) and c), In addition to molecular materials, SiO, MgF, S
Inorganic compounds such as iO ₂ , TiO, ZnO, TiN, SiN, Zn, Cu, Ni, Cr, Ge, Se, Au, A
Metals or semimetals such as g and Al can be used. For the purpose of d), an organic thin film having a metallic luster such as a metal such as Al, Au and Ag or a methine dye or a xanthene dye can be used, and e) and f).
For this purpose, an ultraviolet curable resin, a thermosetting resin, a thermoplastic resin or the like can be used. The thickness of the undercoat layer is
0.01 to 30 μm, preferably 0.05 to 10 μm
And

<< Metal Reflective Layer >> The metal reflective layer is used when necessary depending on the required reflectance. Examples of the material of the metal reflective layer include metals and semi-metals which are highly corrosive and hardly corroded, and specific examples thereof include Au, Ag and C.
Although r, Ni, Al, Fe, Sn and the like can be mentioned, Au, Ag and Al are most preferable from the viewpoint of reflectance and productivity.
These metals and semimetals may be used alone or in the form of an alloy of two kinds. Examples of the method for forming the reflective film include vapor deposition and spattering, and the film thickness is 50 to 5000.
Å, preferably 100 to 3000 Å.

<< Protective Layer, Substrate-side Hard Coat Layer >> The protective layer and the substrate-side hard coat layer are: a) protection of the recording layer (reflective / absorptive layer) from scratches, dust, dirt, etc. b) recording layer (reflective / absorptive) It is used for the purpose of improving the storage stability of the layer) and c) improving the reflectance. For these purposes,
The materials shown for the undercoat layer can be used. Further, SiO, SiO ₂ or the like can be used as the inorganic material, and polymethyl acrylate, polycarbonate, epoxy resin, polystyrene, polyester, vinyl resin, cellulose, aliphatic hydrocarbon resin, natural rubber, styrene butadiene resin can be used as the organic material. It is also possible to use heat-softening and heat-melting resins such as chloroprene rubber, wax, alkyd resin, drying oil and rosin. The most preferable of the above materials is an ultraviolet curable resin having excellent productivity. The thickness of the protective layer or the hard coat layer on the substrate surface is 0.01 to 30 μm, preferably 0.05 to 10 μm.
m. Incidentally, in the undercoat layer, the protective layer, and the substrate surface hard coat layer, as in the case of the recording layer, a stabilizer, a dispersant, a flame retardant, a lubricant, an antistatic agent, a surfactant, a plasticizer and the like. Can be included.

The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples.

Examples 1-3 Poly (aminostyrene) having a number average molecular weight of about 50,000
Block copolymers having a volume fraction of isoprene of 23 vol% (Example 1), 31 vol% (Example 2), and 51 vol% (Example 3) were synthesized from and of isoprene by the living radical method. These block copolymers were dissolved in a mixed solvent of pyridine / chloroform (1/9 weight ratio), and this solution was used to form a cast film on mica. The phase separation structure of these cast films is
By SAXS (small X-ray scattering method) measurement and TEM (transmission electron microscope) observation, a spherical structure (Example 1), a columnar structure (Example 2), and a lamella structure (Example 3) each having a diameter of several tens of nm or less were obtained. It was confirmed that there is. Next, these cast films were immersed in a 0.5 wt% methanol / pyridine (20/1 weight ratio) solution of an SbF ₆ complex of tris (p-dimethylaminophenyl) methane. By TEM observation of the surface layer of these cast films, it was confirmed that the dye was present in the spherical structure, columnar structure, or lamella structure made of poly (aminostyrene).

Example 4 On the cast film having the lamella structure formed in Example 3, 3,
3,3 ', 3'-Tetramethyl-1,1'-bis (3-
A 1 wt% aqueous solution of a triethylamine salt of (sulfoethyl) -2,2′-indodicarbocyanine hydroxide was added dropwise and dried. Next, this film was heat treated at 120 ° C. for 5 hours and then washed with water to remove the surface dye layer. By TEM observation of the surface layer of this cast film, it was confirmed that the pigment was present in the lamellar structure composed of poly (aminostyrene).

Example 5 From poly (4-vinylpyridine) having a number average molecular weight of about 70,000 and isoprene, the volume fraction of isoprene is 49.
A vol% block copolymer was synthesized by the living radical method. This copolymer and iodide-tris (p-dimethylaminophenyl) methyl were used as a copolymer / dye (0.5 /
9.5% by weight) isopropyl alcohol / pyridine /
It was dissolved in a mixed solvent of chloroform (0.5 / 1 / 8.5 weight ratio), and this solution was used to form a cast film on mica. Next, this cast film was heat-treated at 110 ° C. for 5 hours. It was confirmed by SAXS measurement and TEM observation that the phase-separated structure of the cast film was a lamellar structure, and further that the pigment was present in the lamellar structure of poly (4-vinylpyridine).

From the above results, the cast films prepared in Examples 1 to 5 are novel organic thin films in which nanometer-sized spherical, columnar, and lamellar functional dye dispersion structures are constructed in an organic polymer. Became clear. Therefore,
From the function of the functional dye and the highly ordered structure,
Expectation of new electronic, conductive, and optical properties.

Example 6 The volume fraction of isoprene synthesized in Example 3 was 51 vol.
% Block copolymer pyridine / chloroform (1 /
(9 weight ratio) The solution was spin-coated on a quartz substrate having a thickness of 1 mm and a length of 5 cm, and the rotation was stopped when the solvent was uniformly spread. Next, the solvent was cast in a petri dish, dried, and then heat-treated at 100 ° C. for 30 minutes. After confirming that the phase separation structure of the cast film was a lamella structure by TEM observation, 0.5 wt% methanol of SbF ₆ complex of tris (p-dimethylaminophenyl) methane was added in the same manner as in Examples 1 to 3. / Pyridine (20/1 weight ratio)
A recording medium was obtained by impregnating the lamella structure of With respect to this recording medium, the oscillation wavelength was 635 nm and the beam diameter was 1.
The semiconductor laser of 0 .mu.m, was 1.0 cm ² scanned at 1.5μm intervals in the horizontal direction. With respect to the irradiated portion and the non-irradiated portion, TEM observation, observation with an optical microscope, measurement of reflectance and transmittance by microspectroscopic method, and fluorescence observation were performed.

Comparative Example 1 In the same manner as in Example 6, the volume fraction of isoprene was 51 v.
A cast film of an ol% block copolymer was prepared and used as a recording medium as it was without impregnation with a dye. A laser beam was scanned on this recording medium in the same manner as in Example 6.

The evaluation results of Example 6 and Comparative Example 1 are shown in Table 1 below.

[Table 1]

From the results shown in Table 1 above, it became clear that the cast film of Example 6 could be recorded by laser light. In addition, comparing the results of Example 6 and Comparative Example 1,
In Example 6, it is clear that the dye present in the poly (aminostyrene) was recorded. Furthermore, in Example 6, since recording was performed with a light source having a beam diameter (1.0 μm) larger than the diameter of the dye dots (tens of nm), a large number of dye dots were recorded at one time. It is clear that dye dots can be recorded individually by recording with the same beam diameter.

[0028]

INDUSTRIAL APPLICABILITY According to the present inventions 1 to 3, functional dyes having a nanometer-sized spherical, columnar, lamellar or other co-continuous state, or a similar structure thereof, which is expected to be applied as an electronic material or an optical material. It is possible to provide a novel organic thin film having a dispersed structure constructed in an organic polymer. Particularly according to Invention 1,
The present invention provides the basic structure and material composition of an organic thin film.
By 3 to 3, it is possible to provide a preferable application shape and material properties of the organic thin film. According to the present inventions 4 to 6, the present inventions 1 to 3
The method for producing the organic thin film can be provided. According to the present inventions 7 to 10, by using an organic thin film as a recording layer material of an optical recording medium, it is possible to record and reproduce at a recording density exceeding a diffraction limit of a pickup lens which cannot be realized by a conventional optical disc. A density optical recording medium can be provided. Inventions 11 to 1
According to 2, it is possible to provide a preferable recording / reproducing method for the ultra-high density optical recording medium.

[Brief description of drawings]

FIG. 1 is a view showing an example of an organic thin film of the present invention in which a functional dye is contained in only one phase of a micro phase separation structure. (A) An example in which a functional pigment is contained in a spherical structure (b) An example in which a functional pigment is contained in a columnar structure (c) A functional pigment is contained in one lamella of an alternating lamella structure Example of inclusion

FIG. 2 is a diagram showing an example of the layer structure of an optical recording medium in which the recording layer is composed of the organic thin film of the present invention. (A) Optical recording medium consisting of substrate and recording layer only (b) Optical recording medium consisting of substrate, recording layer and reflecting layer (c) Optical recording medium in which the order of recording layer and reflecting layer is reversed

[Explanation of symbols]

1 substrate 2 recording layers 3 reflective layer

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasunobu Uemura             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh (72) Inventor Noguchi Mune             1-3-3 Nakamagome, Ota-ku, Tokyo Stocks             Company Ricoh F-term (reference) 2H111 EA03 EA04 EA22 EA23 EA25                       EA32 FA01 FB42 GA01                 2H123 AA00 AA01 AA02 AA03 AA04                       AA05 AA06 AA08 AA09 AA10                       AA12 AA15 AA22 AA24 CA00                       CA21 CA22 CA31 CA32 CA33                       CA34                 5D029 JB47 JC01 JC03 JC06

Claims (12)

[Claims] 1. A main component is a block copolymer composed of two or more kinds of polymer blocks which are incompatible with each other, and has a micro phase separation structure, and the functional dye is present only in one phase of the micro phase separation structure. An organic thin film characterized by being contained. 2. The organic thin film according to claim 1, wherein the microphase-separated structure is a sphere, a columnar shape, a lamella-like co-continuous shape, or a structure similar thereto. 3. The organic thin film according to claim 1, wherein the functional dye comprises a dye having a function of changing its optical characteristics by light or heat. 4. A solution containing a block copolymer composed of two or more kinds of polymer blocks which are incompatible with each other, and a functional dye having compatibility with only one phase of a microphase-separated structure, Next, after forming a thin film from the solution, a micro phase separation structure is formed by solvent casting or temperature change, The method for producing an organic thin film according to claim 1, wherein 5. A microphase-separated structure is prepared by preparing a solution containing a block copolymer composed of two or more kinds of polymer blocks which are incompatible with each other, and then forming a thin film from the solution, followed by solvent casting or temperature change. And then contacting with a solution containing a functional dye that is compatible with only one phase of the microphase-separated structure, the organic thin film according to claim 1. Production method. 6. A microphase-separated structure is prepared by preparing a solution containing a block copolymer composed of two or more polymer blocks incompatible with each other, forming a thin film from the solution, and then solvent casting or temperature change. A functional dye that is compatible with only one phase of the microphase-separated structure is further laminated thereon, and then the functional dye is heated and diffused. 4. The method for producing an organic thin film as described in 3 above. 7. An optical recording medium comprising the organic thin film according to claim 1 as a recording layer material. 8. The optical recording medium according to claim 7, which contains a functional dye whose wavelength is controlled to have a maximum absorption wavelength in the vicinity of the wavelength of the recording / reproducing laser beam. 9. The optical recording medium according to claim 7, which contains a functional dye whose wavelength is controlled to have a maximum refractive index in the vicinity of the wavelength of the recording / reproducing laser beam. 10. The optical recording medium according to claim 7, wherein the functional dye is a photochromic dye. 11. The recording / reproducing is performed by changing the optical characteristics of one phase of the micro phase separation structure containing the functional dye by irradiating the laser beam.
0. The recording / reproducing method for the optical recording medium according to any one of 0. 12. The recording / reproducing method for an optical recording medium according to claim 11, wherein the optical characteristic is a fluorescent characteristic.