JP2006241282A - Organic thin film and optical recording medium using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new organic thin film constructing a dispersed structure of a functional dye of a nano-meter size in an organic polymer and to provide an ultrahigh-density optical recording medium carrying out recording and reproduction at a recording density which cannot be achieved with a conventional optical recording medium and exceeds the diffraction limit of a pick-up lens by applying the organic thin film to the optical recording medium and thereby providing the optical recording medium in which the area itself of a recording unit is smaller than the diffraction limit of irradiated light and the recording unit is changed into dot rows. <P>SOLUTION: The organic thin film has a micro-phase separation structure formed with a block copolymer in which mutually incompatible polymer chains are bound. Furthermore, the functional dye is contained in a polysilane structural part in which the polymer chain forming one separation phase of the micro-phase separation structure is degraded by irradiating the structure having a polysilane structure with light. The optical recording medium is obtained by using the organic thin film. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention provides an organic compound as a functional composite material that exhibits new functions such as electronic properties, conductive properties, optical properties, etc. by introducing a nanometer-sized functional dye into a polymer and compositing it. The present invention relates to a thin film and an ultra-high density optical recording medium using the same.

  It is known to use a microphase separation structure of a block copolymer having incompatible polymer chains as a functional material (Patent Documents 1 to 11, etc.). In addition, introducing a nanometer-sized functional material into a polymer and compositing it makes it possible to create a functional composite material that exhibits new functions such as electronic properties, conductive properties, optical properties, and magnetic properties. This is an important technology for obtaining metal-organic composite materials using ultrafine metal particles (metal nanoclusters) as functional materials (Patent Documents 2 to 9, etc.). Furthermore, examples in which a dye is used as a functional material and applied to an optical recording medium are also known (Patent Documents 10 to 11). However, the research and development of composite materials of nanometer-sized functional organic materials and polymers that can be expected to have unlimited material flexibility and functionality have not been sufficiently advanced. Moreover, although the said patent documents 10-11 are related to the prior application of the present applicant, there are cases in which functional dyes are not easily segregated in one phase of microphase separation in subsequent studies. I understand.

On the other hand, in the optical memory field, CD-R, DVD-R, and DVD + R that are recordable CD-R, DVD-R, and DVD + R, which are optical recording media having a reflective layer on a substrate, have been commercialized. In such an optical recording medium, further increase in recording capacity and downsizing of recording pits are desired, and further improvement in recording density is required to realize this.
As elemental technologies for improving the recording capacity in the current system, there are recording pit miniaturization technology and image compression technology represented by MPEG2. As technology for miniaturization of recording pits, it has been studied 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 impossible. It is.
Therefore, super-resolution technology capable of recording and reproduction exceeding the diffraction limit and optical memory systems using near-field light have attracted attention as promising means, but they have not yet been put into practical use due to the high technical hurdles. .

Japanese Patent No. 3197507 Japanese Patent No. 2980899 Japanese Patent No. 3000000 Japanese Patent No. 3197500 Japanese Patent No. 3227109 Japanese Patent No. 3244653 Japanese Patent Laid-Open No. 10-330528 JP 2001-151834 A JP 2004-306404 A JP 2003-89269 A JP 2003-94825 A

  The present invention provides a novel organic thin film in which a nanometer-sized functional dye dispersion structure, which is expected to be applied as an electronic material or an optical material, is constructed in an organic polymer, and uses the organic thin film as an optical recording medium. By applying an optical recording medium in which the area of the recording body itself is smaller than the diffraction limit of the irradiated light and the recording body is formed into a dot array, diffraction of the pickup lens that cannot be realized with a conventional optical recording medium. An object of the present invention is to provide an ultra-high density optical recording medium capable of recording and reproducing at a recording density exceeding the limit.

As a result of various studies, the present inventors have made use of the microphase separation phenomenon of the block copolymer, using polysilane for one phase, photoirradiating the polysilane with light irradiation, We succeeded in obtaining the target organic thin film by containing only functional dyes.
Furthermore, by using the organic thin film as an optical recording medium, an ultrahigh density optical recording medium capable of recording / reproducing at a recording density exceeding the diffraction limit of the laser pickup has been obtained.
That is, the above-described problems are solved by the following inventions 1) to 9).
1) A structure having a microphase-separated structure formed by a block copolymer in which incompatible polymer chains are bonded to each other, and a polymer chain forming one separated phase of the microphase-separated structure has a polysilane structure An organic thin film characterized in that a polysilane structure portion decomposed by irradiating with light contains a functional dye.
2) The organic thin film according to 1), wherein the microphase separation structure of the separation phase formed by the polysilane structure is spherical, columnar, lamellar, co-continuous, or a structure similar to each of these shapes.
3) The organic thin film according to 1) or 2), wherein the microphase separation structure is formed by solution casting and temperature change.
4) The organic thin film as described in any one of 1) to 3) above, wherein the light irradiated is ultraviolet light.
5) The organic thin film according to any one of 1) to 4), wherein a functional dye is introduced into the microphase separation structure by a wet method.
6) An optical recording medium comprising the organic thin film according to any one of 1) to 5) as a recording layer.
7) The optical recording medium according to 6), wherein the organic thin film contains a functional dye whose wavelength is controlled so as to have a maximum absorption wavelength in the vicinity of the wavelength of the recording / reproducing laser.
8) The optical recording medium according to 6), wherein the organic thin film contains a functional dye whose wavelength is controlled so as to have a maximum refractive index in the vicinity of the wavelength of the recording / reproducing laser.
9) The optical recording medium according to 7) or 8), wherein the functional dye is a photochromic dye.

Hereinafter, the present invention will be described in detail.
The organic thin film of the present invention has a microphase separation structure formed by a block copolymer in which incompatible polymer chains are bonded to each other, and the polymer chain forming one separated phase of the microphase separation structure is polysilane. The structure having the structure is irradiated with light to cause photolysis of the polysilane structure, and then a functional dye is contained in this phase.
The feature of this organic thin film is that the functional dye is nanometer-sized and highly ordered in the polymer matrix. The micro phase separation phenomenon of the block copolymer is used as the driving force. As the microphase-separated structure, a spherical shape, a columnar shape, a lamellar shape, a co-continuous shape or a similar structure thereof can be used, and the functional dye is preferably composed of a dye having a function of changing its optical characteristics by light or heat. .
FIG. 1 schematically shows a typical microphase separation structure of the organic thin film of the present invention. This shows a state in which the phase containing the functional dye is microphase-separated in the photo-decomposed polysilane structure. Functional dyes are contained in the spherical structure portion in FIG. 1A, the columnar structure portion in FIG. 1B, and the alternating lamellar structure portion in FIG. 1C.
By introducing nanometer-sized functional dyes into the polymer in this way, highly functionally controlled in a three-dimensional manner and composited, new functions such as electronic properties, conductive properties, and optical properties can be obtained. An organic thin film can be realized.

（式中、Ｒ_１、Ｒ_２、Ｒ_３、Ｒ_４はそれぞれ炭素数１〜２０の置換又は無置換のアルキル基、アリール基又はアラルキル基を示す。） It is known that the polysilane structure used in the present invention is broken into Si—OH by ultraviolet irradiation. At that time, since the refractive index is lowered, it is possible to use the polysilane portion in the microphase separation structure as a recording material to obtain an optical recording medium.
However, in the present invention, a thin film in which the polysilane structure is converted to Si-OH by ultraviolet irradiation is brought into contact with a functional dye solution (wet method), for example, so that the polysilane having a microphase-separated structure is functionalized in the photolyzed portion. Introduce dye. In this case, it is preferable to use an aqueous solution of a functional dye.
The block copolymer in the present invention can be synthesized by combining incompatible polymers with each other. It may be a combination of two or more polymers. However, one polymer has a polysilane structure.
The polysilane used in the present invention may be a known one, but particularly preferably has a structure represented by the following general formula [Chemical Formula 1].

(Wherein R ₁ , R ₂ , R ₃ and R ₄ each represent a substituted or unsubstituted alkyl group, aryl group or aralkyl group having 1 to 20 carbon atoms.)

  Examples of the synthesis method of the block copolymer used in the present invention include polysilanes, styrene, isoprene, α-methylstyrene, chloromethylstyrene, 2-vinylpyridine, aminostyrene, 4-vinylpyridine, methacrylates, ε- Living polymerization method (anionic polymerization, living radical polymerization) in which polymerization is carried out from the ends of mutually incompatible polymer chains obtained using caprolactone, butadiene, vinyl methyl ether, 1,3-cyclohexanediene, ethylene oxide, incompatible with each other It can be synthesized by a polymerization method such as a living polymerization (anionic polymerization) synthesized from the center of the polymer chain, or a synthetic method (anionic polymerization, living radical polymerization, etc.) in which the terminal of a terminal functional polymer is bonded.

Next, an optical recording medium using the organic thin film as a recording material (recording layer) will be described.
A conventional optical recording medium includes a recording layer composed of a continuous recording material (a layer in which the recording material exists). The recording layer is irradiated with a laser beam, and some change corresponding to the shape of the laser beam ( Recording is performed by causing a recording material to generate a physical or chemical change accompanied by an optical change. Therefore, since the size of the minimum recording pit depends on the laser beam diameter determined by the oscillation wavelength of the optical system and the NA of the lens, in the conventional recording / reproducing system, the increase in density is basically the laser oscillation wavelength or lens. Has been influenced by the practical technology of NA.
Also, since the beam shape is a Gaussian distribution and there is almost no material that changes with a clear threshold for heat or light as the recording material, the size and change of the outermost circumference of the pits formed The amount is not uniform, and there is always a variation factor in the reproduction signal quality, and there is a limit to obtaining high quality signal characteristics.

  On the other hand, the optical recording medium of the present invention is an optical recording medium having a new structure that overcomes the problems of conventional optical recording media. That is, in the optical recording medium to which the organic thin film of the present invention is applied, the recording layer dots present in a highly ordered manner are discontinuously present through the matrix. In addition, the recording layer dots have a uniform nanometer size (10 to 500 nm). Therefore, the size of the minimum recording pit is not determined by the laser oscillation wavelength or lens NA, but is determined only by the recording layer dots to be formed, and an optical recording medium having an arbitrary recording density can be designed. In addition, since the outermost peripheral edge of the pit is also determined by the structure of the organic thin film, high quality signal characteristics without pit variations can be obtained by recording the entire recording layer dot. Is possible.

The configuration of the optical recording medium of the present invention and the necessary physical properties thereof will be described.
<Recording medium configuration>
The optical recording medium of the present invention has a recording layer composed of the organic thin film and a functional dye on a substrate, but if necessary, an undercoat layer, a metal reflective layer, a protective layer, a substrate surface hard coat layer as other constituent layers The form of the constituent layer is selected according to the purpose and required characteristics.
For example, the structural example as shown to the schematic sectional drawing of Fig.2 (a)-(d) and Fig.3 (a)-(e) is mentioned. 2A to 2D are examples in which a metal reflective layer is not provided on a substrate, and FIGS. 3A to 3E are examples in which a metal reflective layer is provided. 2 and 3, the recording layer portion is the organic thin film of the present invention.
The structure of the optical recording medium of the present invention may be a write-once optical disk structure (a so-called air sandwich structure in which two recording layers are provided on a substrate), or a CD-R structure (recording on a substrate). A structure in which a layer, a reflective layer, and a protective layer are provided) or a DVD structure in which a CD-R structure is bonded. The above configuration is an example for describing the embodiment, and other configurations may be used.

Each constituent layer of the optical recording medium of the present invention will be described.
<substrate>
The substrate must be transparent to the laser used when recording / reproduction is performed from the substrate side, but is transparent to the laser used when recording / reproduction is performed from the recording layer side (the side opposite to the substrate). There is no need.
As the substrate material, for example, plastics such as polyester resin, acrylic resin, polyamide resin, polycarbonate resin, polyolefin resin, phenol resin, epoxy resin, polyimide resin, glass, ceramic, metal, and the like can be used. Note that a guide groove for tracking, a guide pit, and a preformat such as an address signal may be formed on the surface of the substrate.

<Recording layer>
The recording layer is capable of causing some optical change upon irradiation with laser light, and recording and reproducing information by the change, and two or more incompatible blocks containing a polysilane structure on one side The polysilane structure is photodecomposed by irradiating the microphase separation structure with a copolymer as a main component, and a functional dye is contained only in the phase.
As for the optical characteristics of the functional dye, when reproducing using the change in absorption characteristics with respect to the recording / reproducing laser wavelength, it is preferable to control the wavelength so as to have the maximum absorption wavelength near the laser wavelength. When reproduction is performed using the refractive index change with respect to the reproduction laser wavelength, it is preferable to control the wavelength so that the maximum refractive index is in the vicinity of the laser wavelength.
Further, as a reproduction method, a method of reproducing the change by changing the fluorescence characteristic by laser irradiation enables reproduction with high contrast even with a slight change, and the size of the recording pit as in the optical recording medium of the present invention is started. In particular, recording with significantly lower energy is possible as compared with the conventional method. In the conventional method, a clear pit shape must be formed by recording, and recording cannot be performed unless the reaction rate of the recording material by laser irradiation is high. On the other hand, the optical recording medium of the present invention in which pits are already formed can be reproduced even with a small reaction rate, and fluorescence reproduction is particularly effective.

Examples of functional dyes include polymethine-based, squarylium-based, pyrylium-based, porphyrin-based, porphyrazine-based, azo-based, and azomethine-based dyes whose optical constants are changed in a heat mode (thermal decomposition or the like) by laser irradiation energy. And its metal complex compounds, fulgides that change their optical constants in photon mode depending on laser irradiation energy, diarylethenes, azobenzenes, spiropyrans, stilbenes, dihydropyrenes, thioindigos, bipyridines, aziridines, aromatics Photochromic materials such as group polycyclics, allylidene anilines, xanthenes, etc., and photochromic materials capable of rewriting recording are particularly preferable. The above dyes may be used alone or in combination of two or more. Furthermore, 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, or the like may be added to the dye for the purpose of improving characteristics. Good.
The dot diameter of the functional dye is 5 to 500 nm, preferably 10 to 200 nm.

<Underlayer>
The undercoat layer consists of (1) improved adhesion, (2) a barrier such as water or gas, (3) improved storage stability of the recording layer, (4) improved reflectance, and (5) a substrate from a solvent. And (6) formation of guide grooves, guide pits, and preformats.
For the purpose of (1), polymer materials such as ionomer resins, polyamide resins, vinyl resins, natural resins, natural polymers, silicones, various rubber compounds such as liquid rubber, and silane coupling agents. Can be used. For the purposes of (2) or (3), in addition to the above polymeric _{materials, SiO, MgF, SiO 2,} TiO, ZnO, TiN, and inorganic compounds such as SiN, Zn, Cu, Ni, Cr, A metal or a semimetal such as Ge, Se, Au, Ag, or Al can be used. For the purpose of (4), an organic thin film having a metallic luster such as metals such as Al, Au and Ag, methine dyes and xanthene dyes can be used. For the purpose of (5) or (6), 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.

<Metal reflective layer>
The metal reflective layer is used when necessary according to the required reflectance.
The reflective layer is made of a metal or semi-metal that is not easily corroded and has a high reflectivity, and examples thereof include Au, Ag, Cr, Ni, Al, Fe, and Sn. Among these, Au, Ag, and Al are most preferable from the viewpoint of reflectance and productivity. These metals or metalloids may be used alone or as two kinds of alloys.
The method for forming the reflective layer is not particularly limited, and examples thereof include vapor deposition and sputtering.
The thickness of the reflective layer is preferably 50 to 5000 mm, and more preferably 100 to 3000 mm.

<Protective layer, hard coat layer on substrate surface>
The protective layer and the hard coat layer on the substrate surface are (1) protection from scratches, dust and dirt on the recording layer (reflection / absorption layer), (2) improvement in storage stability of the recording layer (reflection / absorption layer), (3 ) Used for the purpose of improving the reflectance. For these purposes, the materials shown for the undercoat layer can be used.
In addition, SiO, SiO ₂ or the like can be used as the inorganic material, and polymethyl acrylate, polycarbonate, epoxy resin, polystyrene, polyester resin, vinyl resin, cellulose, aliphatic hydrocarbon resin, natural rubber, styrene butadiene as the organic material. Thermosoftening and heat melting resins such as resins, chloroprene rubber, waxes, alkyd resins, drying oils and rosins can also be used.
The most preferable among the above materials is an ultraviolet curable resin excellent in productivity.
The film thickness of the protective layer or the substrate surface hard coat layer is 0.01 to 30 μm, preferably 0.05 to 10 μm.
As in the case of the recording layer, the undercoat layer, protective layer and substrate surface hard coat layer contain a stabilizer, a dispersant, a flame retardant, a lubricant, an antistatic agent, a surfactant, a plasticizer, and the like. Can do.

  According to the present invention, a nanometer-sized functional dye dispersion structure, which is expected to be applied as an electronic material or an optical material, is constructed in an organic polymer, and a novel organic thin film can be provided. In addition, by applying the organic thin film to an optical recording medium, an optical recording medium in which the area of the recording body itself is smaller than the diffraction limit of irradiation light and the recording body is arranged in a dot array is used. Thus, it is possible to provide an ultra-high density optical recording medium that can be recorded and reproduced at a recording density exceeding the diffraction limit of the pickup lens, which is impossible to realize.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further more concretely, this invention is not limited by these Examples.

次に、作製されたキャスト膜に対し高圧水銀ランプにより光照射（１Ｊ／ｃｍ^２）を行い、ポリシラン部の光分解を行った。更に、この膜を、３，３，３’，３’−テトラメチル−１，１’−ビス（３−スルホエチル）−２，２’−インドジカルボシアニンヒドロキシドのトリエチルアミン塩（色素）の１重量％水溶液に浸漬させた。
この薄膜の表面層のＴＥＭ観察により、色素はＰＳｉ−１を光分解させた部分に偏析していることが確認された。 Examples 1-3
It consists of polysilane (PSi-1) represented by the following general formula [Chemical Formula 2] having a number average molecular weight of about 20000 and polystyrene (PSt), and the volume fraction of PSi-1 is 15% by volume (Example 1), A block copolymer of 32% by volume (Example 2) and 54% by volume (Example 3) was synthesized by living polymerization.
This copolymer was dissolved in toluene to form a cast film on a silicon wafer.
Furthermore, when this cast film was heat-treated at 140 ° C. for 6 hours, the phase separation structure was measured by SAXS measurement and TEM observation, each having a spherical structure (Example 1) or columnar structure (Example 2) of several tens of nm or less, The lamellar structure (Example 3) was confirmed.

Next, the produced cast film was irradiated with light (1 J / cm ² ) with a high-pressure mercury lamp, and the polysilane part was photolyzed. Further, this membrane was formed by using 1 of triethylamine salt (dye) of 3,3,3 ′, 3′-tetramethyl-1,1′-bis (3-sulfoethyl) -2,2′-indodicarbocyanine hydroxide. It was immersed in a weight% aqueous solution.
By TEM observation of the surface layer of this thin film, it was confirmed that the dye was segregated in the portion where PSi-1 was photolyzed.

次に、作製されたキャスト膜に対し高圧水銀ランプにより光照射（１．５Ｊ／ｃｍ^２）を行い、ポリシラン部の光分解を行った。
更に、この膜をトリス（ｐ−ジメチルアミノフェニル）メチリウムＳｂＦ_６（色素）の０．５重量％メタノール／ピリジン＝２０／１溶液の中に浸漬させた。この薄膜の表面層のＴＥＭ観察により、色素はＰＳｉ−２を光分解させた部分に偏析していることが確認された。 Example 4
A block copolymer consisting of polysilane (PSi-2) and polymethyl methacrylate (PMMA) represented by the general formula [Chemical Formula 3] having a number average molecular weight of about 10,000, and having a volume fraction of PSi-2 of 28% by volume. Was synthesized by living polymerization.
This copolymer was dissolved in propylene glycol monomethyl ether to form a cast film on a silicon wafer.
Furthermore, when this cast film was heat-treated at 130 ° C. for 8 hours, the phase separation structure was confirmed to be a columnar structure of several tens of nm or less by SAXS measurement and TEM observation.

Next, the produced cast film was irradiated with light (1.5 J / cm ² ) with a high-pressure mercury lamp, and the polysilane part was photolyzed.
Further, this membrane was immersed in a 0.5 wt% methanol / pyridine = 20/1 solution of tris (p-dimethylaminophenyl) methylium SbF ₆ (dye). By TEM observation of the surface layer of this thin film, it was confirmed that the dye was segregated in the portion where PSi-2 was photolyzed.

  From the above results, it was confirmed that a nanometer-sized spherical, columnar, and lamellar functional dye-dispersed structure can be produced in an organic polymer. New electronic properties, conductive properties, and optical properties are expected from the function of the functional dye and the highly ordered structure.

Comparative Example 1
A block copolymer composed of polystyrene and polyisoprene having a number average molecular weight of 20,000 and having a polystyrene volume fraction of 48% was synthesized by living polymerization.
This copolymer was dissolved in chloroform to form a cast film on a silicon wafer.
Furthermore, when this cast film was heat-treated at 130 ° C. for 10 hours, the phase separation structure was confirmed to be a lamella structure of several tens of nm or less by SAXS measurement and TEM observation.
Next, a triethylamine salt of 3,3,3 ′, 3′-tetramethyl-1,1′-bis (3-sulfoethyl) -2,2′-indodicarbocyanine hydroxide ( Dye) was immersed in a 1% by weight aqueous solution.
When this thin film was observed with a TEM, it was confirmed that the dye did not segregate in either phase and showed a distribution unrelated to the microphase separation structure.

Comparative Example 2
In Example 4, a thin film was formed in exactly the same manner as in Example 4 except that no light was irradiated with a high-pressure mercury lamp. When the surface layer of this thin film was observed by TEM, it was confirmed that the dye did not segregate in either phase and showed a distribution unrelated to the microphase separation structure.
This is considered to be caused by the fact that the affinity for the dye does not increase because the polysilane structure does not undergo photodecomposition and become a Si—OH structure.

Example 5
The toluene solution of the block copolymer synthesized in Example 3 was spin-coated on a 1 mm thick, 5 cm square quartz substrate. However, the spin coating stopped rotating when the solvent spread evenly. Then, it dried and heat-processed at 140 degreeC for 6 hours.
After confirming that the phase separation structure of the organic thin film thus obtained was a lamella structure by TEM observation, this thin film was irradiated with light (1 J / cm ² ) with a high-pressure mercury lamp, and the polysilane part was photolyzed. . Furthermore, it was immersed in a dye aqueous solution in the same manner as in Example 3, and the dye was introduced into a lamellar structure composed of a portion where PSi-1 was photodegraded to obtain an organic thin film having a recording material.
For this organic thin film, a semiconductor laser having an oscillation wavelength of 635 nm and a beam diameter of 1 μm was scanned 1.0 cm ^{2 in the} horizontal direction at intervals of 1.5 μm.
With respect to the irradiated part and the unirradiated part, observation with a TEM, an optical microscope, and measurement of reflectance and transmittance by a microspectroscopic method were performed. The results are shown in Table 1.

Comparative Example 3
An organic thin film having a recording material was prepared and recorded in the same manner as in Example 5 except that it was not immersed in the dye solution. The results are shown in Table 1.

From the results in Table 1, it was revealed that the cast film of Example 5 was recordable with a laser. From comparison with the result of Comparative Example 3, it is clear that the recording was made on the functional dye embedded in the portion where PSi-1 was photolyzed.
In this experiment, recording was performed with a light source having a larger beam diameter (1 μm) than the functional dye dot diameter (several tens of nanometers), so a large number of functional dye dots were recorded at the same time. If the recording is performed with the beam diameter, functional dye dots can be recorded individually.
Since the recording signal can be reproduced as a change in transmittance and a change in reflectance, in the method of reproducing using this phenomenon, the absorption wavelength of the functional dye is most controlled in the vicinity of the oscillation wavelength of the recording / reproducing laser. preferable.

The schematic diagram which shows the typical micro phase-separation structure of the organic thin film of this invention. (A) Spherical structure (sea-island structure), (b) columnar structure, (c) alternating lamellar structure. (A)-(d) This schematic cross-sectional view showing the layer structure of the optical recording medium (without a metal reflection layer). (A)-(e) This schematic sectional drawing which shows the layer structure (with a metal reflective layer) of an optical recording medium.

Claims (9)

  It has a microphase separation structure formed by a block copolymer in which polymer chains incompatible with each other are bonded, and the polymer chain forming one of the separated phases of the microphase separation structure is irradiated with light on a structure having a polysilane structure. An organic thin film characterized in that a polysilane structure portion decomposed by irradiation contains a functional dye.   2. The organic thin film according to claim 1, wherein the microphase separation structure of the separation phase formed by the polysilane structure is spherical, columnar, lamellar, co-continuous, or a structure similar to each of these shapes.   3. The organic thin film according to claim 1, wherein the microphase separation structure is formed by solution casting and temperature change.   The organic thin film according to any one of claims 1 to 3, wherein the light irradiated is ultraviolet light.   The organic thin film according to any one of claims 1 to 4, wherein a functional dye is introduced into the microphase separation structure by a wet method.   An optical recording medium comprising the organic thin film according to claim 1 as a recording layer.   7. The optical recording medium according to claim 6, wherein the organic thin film contains a functional dye whose wavelength is controlled so as to have a maximum absorption wavelength in the vicinity of the wavelength of the recording / reproducing laser.   7. The optical recording medium according to claim 6, wherein the organic thin film contains a functional dye whose wavelength is controlled so as to have a maximum refractive index in the vicinity of the wavelength of the recording / reproducing laser. 9. The optical recording medium according to claim 7, wherein the functional dye is a photochromic dye.

Images