JPH11316973A - Production of optical recording medium and optical recording medium produced by the method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent deformation of pits and grooves on a recording surface by spraying a soln. contg. an optical functional org. compd. in a manner as to satisfy conditions in such a manner that the soln. can form the this film in a liquid medium- free state and drying the thin film by heating, thereby forming the thin film on the substrate surface of a recording medium. SOLUTION: A thin film forming material is prepd. by dissolving the selected optical functional org. compd. alone or a mixture composed of the compd. and a thermoplastic org. high-polymer compd. in a solvent and the concn. thereof is set according to the thickness of the thin film to be formed. The recording medium substrate 14 is placed in a vacuum chamber 10 and the thin film of the optical functional org. compd. is formed on the surface of the substrate 14 by spraying the film forming material liquid. At this time, the operating conditions of, such as latent heat of evaporation, solidification point temp., a physical constant of an evaporation rate, a nozzle heating temp., spraying rate, the distance between a nozzle 16 and the substrate 14, and a condition for heating mists, are controlled in order to put the sprayed mists or fine liquid droplets into the liquid medium-free state. As a result, the fluidization of the soln. and the direct contact of the medium liquid immersing the substrate with the substrate are prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for manufacturing an optical recording medium for high-density recording, and more particularly to a method for manufacturing a read-only, write-once or rewritable optical disk having a layer containing an organic compound. The present invention also relates to an optical recording medium for high-density recording by the above manufacturing method.

[0002]

2. Description of the Related Art In recent years, compact discs (CDs) have been led, and high-density read-only optical discs, write-once optical discs that can be recorded only once, and rewritable magneto-optical (MO) discs have been developed. And phase change disks (PD, CD-RW) have begun to spread rapidly. Among them, various types of optical disks using a layer containing an organic substance as a recording layer or the like have been developed and put to practical use.

[0003] Organic compounds, compared to metals and inorganic compounds,
Because there are so many types, many functions can be expressed by structural design at the molecular level,
High sensitivity is easy. For example, a recordable CD (CD
In -R), an optical dye dissolved in a liquid medium is spin-coated on a transparent resin substrate having a spiral continuous groove to form a recording layer, thereby providing an inexpensive optical disk with good productivity. I have.

[0004] Also, research has been conducted on an optical disk in which a mask layer having a reversible dye such as a thermochromic compound or a photochromic compound is formed on a transparent substrate in which information is recorded in advance as pits, a so-called super-resolution optical disk. I have.

[0005] In an optical disk having such a mask layer formed thereon, the wavelength of a laser to be irradiated is controlled by utilizing the nonlinear change of light transmittance with respect to light intensity of a reversible dye such as a thermochromic compound or a photochromic compound. The laser beam spot diameter, which is limited by the numerical aperture (NA) of the pickup lens, is reduced to a smaller spot diameter by transmitting the laser beam only through a region having a strong light intensity distribution, thereby reducing the pit size. , And as a result, higher densification has been achieved.

Conventionally, as a method for forming a layer containing an organic compound as described above on a substrate, the above-described spin coating method is known. For example, in a write-once optical disc using an organic dye for a recording layer such as a CD-R, usually, an organic dye dissolved in a liquid medium is spin-coated on a transparent resin substrate having spiral continuous grooves. A recording layer is formed. However, in next-generation optical discs, which have higher recording densities than conventional compact discs and other optical discs, the pit size and depth, or the width and depth of continuous Since the dimensions tend to be smaller, when a layer formed by spin-coating a dye or the like dissolved in an organic liquid medium on a substrate on which such small and shallow pits or fine and shallow grooves are formed, these pits and And / or the continuous grooves are buried, making it difficult to perform tracking during recording or reproduction.

Further, most of the recent optical disks are
From the viewpoint of cost and mass productivity, a non-crystalline and light-transmitting thermoplastic resin represented by polycarbonate is used as the substrate. However, this non-crystalline thermoplastic resin often has low solvent resistance to organic solvents, and therefore causes the following problems.

(1) The types of organic solvents that can be used when forming a layer containing an organic substance on a substrate by spin coating and do not attack the substrate are limited.

(2) The types of organic substances such as dyes dissolved in an organic solvent that does not attack the substrate are further limited.

On the other hand, in addition to the above-described spin coating method, an optical disk using a vacuum evaporation method has been studied as a method for forming a layer containing an organic compound. For example, Japanese Patent Application Laid-Open No. Hei 7-18693 discloses an example of an optical disk in which a mask layer having a reversible dye such as a thermochromic compound is formed on a substrate by a heating vacuum deposition method, that is, a so-called super-resolution optical disk. ing. By forming a mask layer having a reversible dye such as a thermochromic compound on a substrate having small pits such as a super-resolution optical disc using a heating vacuum evaporation method, as in the spin coating method described above, A good super-resolution optical disc can be realized without filling the pits and / or the continuous grooves.

[0011]

However, this heating vacuum deposition method is not always satisfactory because of the following restrictions.

(1) The types of organic compounds that can be deposited stably are limited. For example, organic ionic dyes such as cyanine dyes and high molecular compounds do not exhibit sublimability, and thus cannot be formed by heating vacuum evaporation.

(2) Even an organic compound having a sublimation property is generally easily decomposed by heating as compared with an inorganic substance, so that a film forming rate cannot be increased so much and a long time is required for film forming.

(3) Since it is difficult to mix a plurality of types of organic compounds and perform evaporation from a single evaporation source while controlling the respective sublimation rates, it is necessary to simultaneously deposit a plurality of types of organic compounds. In this case, an evaporation source must be prepared for each type of organic compound.

As a method for compensating for such a drawback of the heating vacuum evaporation method, recently, an organic optical material in a solution or dispersion state is sprayed into a high vacuum chamber and deposited on a substrate.
A method for preparing an optical thin film characterized by heat treatment is disclosed in JP-A-6-306181 and JP-A-7-252671, and is disclosed in academic literature [T. Hiraga, et.al., J. Vac. Sci.
Technol., A12 (3), 876-878 (1994) and T. Hiroga, et.a
I., Jpn. J. Appl. Phys., 33 (9A), 5051-5059 (1994)].

JP-A-6-306181 and 7-252
No. 671 reports that the substrate is heated to a temperature not exceeding the thermal decomposition temperature of the deposit to remove volatile components.
It describes heating a substrate and a deposit on the substrate using a substrate heating device and a substrate surface heating device. Even if the substrate placed in the vacuum chamber is heated to a temperature lower than the thermal deformation start temperature (for example, 150 ° C.), a large amount (for example, 50 wt%) is contained in the spray mist reaching the substrate.
When the liquid medium remains, heat of evaporation of the liquid medium is taken from the substrate surface. At this time, if the substrate is a material having high thermal conductivity, such as metal or optical glass, the evaporation heat is immediately supplied from the substrate heater, but if the substrate is an organic material having low thermal conductivity, such as polycarbonate, The substrate surface temperature drops significantly, requiring a long time to evaporate the residual liquid medium. Therefore, to form a thin film on a polycarbonate substrate without destroying information pits and / or continuous grooves on the substrate, the type of liquid medium, the temperature of the solution and the substrate, the spray speed of the liquid, and the It is necessary to set and control conditions such as distance very strictly.

Literature [T.Hiraga, et.al., J.Vac.Sci.Techno
l., A12 (3), 876-878 (1994) and T. Hiraga, et.al., Jpn.
J. Appl. Phys., 33 (9A), 5051-5059 (1994)] describes a spray nozzle heater. This heater is effective in preventing the temperature of the liquid medium from dropping due to the evaporation of the liquid medium in the spray nozzle portion, thereby preventing the liquid medium from solidifying. However, even if the spray nozzle is sufficiently heated, it is difficult to supply in advance the amount of heat necessary for complete evaporation of the liquid medium to the sprayed film-forming material solution or dispersion mist. You. The physical properties of a general organic liquid medium are shown in Table 1. Assuming that the specific heat and the heat of vaporization of the liquid medium are constant in the temperature range from the boiling point to the melting point, the heat of vaporization [unit: J / mol]. Is divided by the specific heat [unit: J / mol / K], the value (T _vp ) of “virtual temperature decrease due to evaporation” can be estimated. Actually, the value of the heat of evaporation increases and the value of the specific heat decreases as the temperature of the liquid medium decreases, so that it is considered that the temperature decreases more than the calculated value. Tables 1 and 2 exemplify this value (T _vp ). For most liquid media, T _vp exceeds the “boiling point-melting point” temperature range (T _vm ) of the individual liquid media. I have. That is, even if a droplet having a boiling point at normal pressure is placed in a space in a vacuum, the temperature of the liquid medium drops to its melting point before the liquid medium is completely evaporated, and becomes a solid. After sublimation, "sublimation" is significantly slower than evaporation. In any case, heating the spray nozzle without destroying the information pits and / or continuous grooves on the polycarbonate substrate without destroying the information pits and / or continuous grooves requires the type of liquid medium, the temperature of the solution and the substrate, It is necessary to set and control conditions such as the liquid spray speed and the distance between the nozzle and the substrate very strictly.

[0018]

TABLE 1 Physical properties of organic solvent [T _vm = [boiling point temperature]-[melting point temperature] T _vp = [heat of evaporation] / [specific heat]] Solvent Boiling point Melting point T _vm Evaporation heat Specific heat T _vp [° C] [° C] [K] [kJ / mol] [J / mol / K] [K] Methanol 64.7 -97.5 162.2 35.27 81.06 435 Ethanol 78.3 -130 208 38.6 111.4 346 Isopropyl alcohol 82.3 -89.5 171.8 41.49 152.89 271 n-Butyl alcohol 117.7 -89.8 207.5 44.39 179 248 Ethyl acetate 77.11 -83.6 160.7 35.62 169 211 Isopropyl acetate 88.6 -73.4 162.0 37.2 223 167 n-Butyl acetate 126.1 -73.5 199.6 43.64 223 196 196 Acetone 56.1 -94.7 150.8 29.6 126.7 234 Methyl ethyl ketone 79.6 -86.3 165.9 32.0 158.1 202 Methyl isobutyl ketone 116.2 -84 200.2 34.6 191.6 181 Diethyl ether 34.6 -116 150.6 26.78 166.9 160 dichloromethane 39.8 -9 -96.7 136.5 27.96 99.4 281 Chloroform 61.3 -63.2 124.5 29.5 117.0 252 Carbon tetrachloride 76.7 -22.9 99.6 29.95 133.2 225 1,2-Dichloroethane 83.7 -35.3 119.0 32.01 127.5 251 Trichloroethylene 86.7 -87.1 173.8 31.5 123.6 255 1,1,2-Trichloroethane 113.7 -37.0 150.7 38.0 148.5 256 Toluene 110.6 -95.2 205.8 33.18 103.3 321 n-pentane 36.0 -129.8 165.8 25.77 118.4 218 n-hexane 68.7 -95.4 164.1---n-heptane 98.4 -90.6 189---Cyclohexane 80.7 6.5 74.2-- -Acetonitrile 81.8 -45.7 127.5 32.8 51.88 632 Propionitrile 97.2 -91.8 189.0---Pyridine 115.5 -42 157.5 35.53 136 261 Triethylamine 89.4 -114.5 203.9---Nitromethane 101.3 -28.4 129.7--- Carbon disulfide 46.3 -111 157.3 26.8 18.26 1468

[0019]

[Table 2] Physical properties of organic solvent [T _vm = [boiling point temperature]-[melting point temperature] T _vp = [heat of evaporation] / [specific heat]] Solvent Boiling point Melting point T _vm Heat of evaporation Specific heat T _vp [° C] [° C] [K] [kJ / mol] [J / mol / K] [K] n-amyl alcohol 138.0 -78.2 216.2 44.48 209 213 Cyclohexanol 161.1 25.2 135.9 45.2 214.98 210 Benzyl alcohol 205.8 -15.3 221.1 53.60 244.42 219 ethylene glycol 197.6 -13 210.6 52.33 150 349 n-Amyl acetate 149.2 -70.8 220.0 41 276 149 Cyclohexanone 155.7 -31.2 186.9 40.2 177.8 226 Dibutyl ether 142.0 -95.4 237.4--- Benzene 80.1 5.5 74.6 30.76 80.8 381 Chlorobenzene 131.7 -45.3 177.0 37.27 150.8 247 Water 100.0 0.0 100.0 40.66 75.42 539

An object of the present invention is to solve the above-mentioned drawbacks of the prior art and to solve the following problems.

1) By evaporating the liquid medium as much as possible from the mist until the mist of the solution or dispersion of the film-forming material sprayed from the nozzle in the vacuum reaches the substrate surface, A film forming method for preventing the mist that has reached from flowing and impairing the shape of recording pits and / or continuous grooves formed on the substrate, and
An optical recording medium manufactured by the method is provided.

2) By evaporating the liquid medium as much as possible from the mist until the mist of the solution or dispersion of the film-forming material sprayed from the nozzle in the vacuum reaches the substrate surface, Provided are a film forming method for preventing recording pits and / or continuous grooves formed on a substrate from being destroyed by dissolving a substrate material, and an optical recording medium manufactured by the method.

[0023]

According to a first aspect of the present invention, there is provided a method for manufacturing an optical recording medium, wherein information is previously recorded as pits and / or continuous grooves on at least one recording surface. At least one of the substrates placed in a vacuum chamber under the condition that a thin film can be formed in a substantially liquid medium-free state so as not to impair the shape of the pits and / or the continuous grooves by using the substrate thus obtained. A solution or a dispersion of a film-forming material containing at least one type of photofunctional organic compound is sprayed on one recording surface, and the thin film is subjected to a heat drying treatment.

In order to achieve the above object, a method of manufacturing an optical recording medium according to a second aspect of the present invention is characterized in that a mist of a solution or a dispersion of the film-forming material sprayed into a vacuum chamber is formed into a mist. It is characterized by supplying the heat of evaporation of the liquid medium in the mist by irradiating light rays and / or heat rays in the wavelength band absorbed by the mist.

According to a third aspect of the present invention, there is provided a method for manufacturing an optical recording medium, wherein the film-forming material consists essentially of at least one kind of the optically functional organic compound. It is characterized by the following.

According to a fourth aspect of the present invention, there is provided a method for manufacturing an optical recording medium, wherein the film-forming material comprises at least one kind of the optically functional organic compound and a binder. It is characterized by comprising a mixture of resins.

According to a fifth aspect of the present invention, there is provided a method for manufacturing an optical recording medium, comprising: using a disk having a diameter of 40 mm to 300 mm as the substrate; The liquid medium has a boiling point at normal pressure of 30 ° C. or higher and 120 ° C. or lower and a melting point of −2.
Using a compound having a temperature of 0 ° C. or less, the film forming conditions were as follows: the pressure in the vacuum chamber was maintained at 1 to 10 ⁻⁶ Pa, and the evacuation speed from the vacuum chamber was 50 liter / min to 100 cubic meters / 100 at 1 atm. Minutes, the distance between the spray nozzle and the substrate is 1 to 10 times the diameter of the substrate, the temperature of the spray nozzle is maintained at a temperature higher than the melting point of the liquid medium and a temperature not higher than the boiling point at normal pressure, Is maintained at least 10 ° C. below the melting point of the liquid medium, and the solution or dispersion is reduced from 1 nanoliter / min to 1
It is characterized by spraying at a spray rate of milliliter / min.

In order to achieve the above object, a method of manufacturing an optical recording medium according to a sixth aspect of the present invention is characterized in that the liquid trap is cooled by liquid nitrogen.

According to a seventh aspect of the present invention, there is provided a method for manufacturing an optical recording medium, wherein a substrate made of a thermoplastic resin is used as the substrate, and the heating and drying temperature of the thin film is reduced. The heat treatment is performed at a temperature not exceeding the thermal deformation starting temperature of the thermoplastic resin.

In order to achieve the above object, a method of manufacturing an optical recording medium according to claim 8 of the present invention is characterized in that a reflective film and a protective film are formed on the thin film.

In order to achieve the above object, the present invention provides an optical recording medium manufactured by the method for manufacturing an optical recording medium according to claim 1 of the present invention.

In the above-mentioned optical recording medium, the substrate preferably has a light transmitting property. Further, in these optical recording media, the substrate is preferably formed of a thermoplastic resin.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a method for manufacturing an optical recording medium according to the present invention, a substrate prepared in advance is used. As the type of the substrate, the aforementioned CD, CD-R, MO, P
D, CD-RW and super-resolution optical discs, digital versatile discs (DVD, DVD-RAM,
DVD-R, DVD-RW). In practicing the present invention, a substrate on which information is recorded in advance on at least one recording surface as pits and / or continuous grooves is used.

The material of the substrate is not particularly limited, but is preferably formed of a light-transmitting material. Specifically, for example, glass, polycarbonate, polymethyl methacrylate, Examples thereof include thermoplastic resins such as non-crystalline polyolefin resins and thermosetting resins such as epoxy resins. Above all, a light-transmitting thermoplastic resin such as polycarbonate is preferable.

Such a substrate is placed in a vacuum chamber, and a solution or dispersion of a film-forming material containing at least one type of photofunctional organic compound is formed on a recording surface on which information is recorded as pits and / or continuous grooves. Is sprayed and further subjected to a heat drying treatment to form a thin film.
Here, “optical functionality” refers to various functions induced by light absorption, such as an optical recording function in an optical disk, a mask function in a super-resolution optical disk, a reversible color development / bleaching phenomenon, photochromism, and thermochromism.

Examples of the photofunctional organic compound include known organic dyes such as general dyes, fluorescent dyes, infrared absorbing dyes, ultraviolet absorbing dyes, photochromic dyes, and thermochromic dyes.
Specific examples of these dyes include, for example, xanthene dyes such as rhodamine B, rhodamine 6G, eosin, and phloxin B; acridine dyes such as acridine orange and acridine red; azo dyes such as ethyl red and methyl red; Dye, phthalocyanine dye, cyanine dye such as 3,3′-diethylthiacarbocyanine iodide, 3,3′-diethyloxadicarbocyanine iodide, merocyanine dye, styryl dye, oxonol dye, triarylmethane dye, spiropyran Preferred are photochromic dyes such as derivatives, fulgide derivatives, and diarylethene derivatives.

In the present invention, the above-mentioned dyes can be used alone or in combination of two or more. Furthermore, these dyes can be used in combination with a binder resin.

The binder resin is not particularly limited, but is preferably, for example, a thermoplastic organic polymer compound. Specifically, polystyrene, poly (α-
Methylstyrene), polyindene, poly (4-methyl-
1-pentene), polyvinyl pyridine, polyvinyl formal, polyvinyl acetal, polyvinyl butyral, polyvinyl acetate, polyvinyl alcohol, polyvinyl chloride, polyvinylidene chloride, polyvinyl methyl ether, polyvinyl ethyl ether, polyvinyl benzyl ether, polyvinyl methyl ketone, poly ( N-vinylcarbazole), poly (N-vinylpyrrolidone), polymethyl acrylate, polyethyl acrylate, polyacrylic acid, polyacrylonitrile, polymethyl methacrylate,
Polyethyl methacrylate, polybutyl methacrylate, polybenzyl methacrylate, polyhexyl methacrylate, polymethacrylic acid, polymethacrylamide, polymethacrylonitrile, polyacetaldehyde, polychloral, polyethylene oxide, polypropylene oxide, polyethylene terephthalate, poly Butylene terephthalate, polycarbonates (bisphenols +
Carbonic acid), poly (diethylene glycol bisallyl carbonate), 6-nylon, 6,6-nylon, 12
-Nylon, 6,12-nylon, ethyl polyaspartate, ethyl polyglutamate, polylysine, polyproline, poly (γ-benzyl-L-glutamate), methylcellulose, ethylcellulose, benzylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, acetylcellulose And resins such as cellulose triacetate, cellulose tributyrate and polyurethane resin, organic polysilanes such as poly (phenylmethylsilane), organic polygermanes, and copolymers or copolycondensates thereof.

The optical recording medium of the present invention can be manufactured as follows. That is, first, the above-described photofunctional organic compound alone or a mixture of the photofunctional organic compound and the thermoplastic organic polymer compound is dissolved or dispersed in a liquid medium to form a thin film forming material in a liquid state. Prepare.

The solvent or dispersing medium (hereinafter referred to as “liquid medium”) used at this time is capable of dissolving or dispersing the above-mentioned thin film forming material, and is volatile and corrosive. No compound is used. Preferably, the boiling point range at 1 atm is 30 ° C. or higher and 120 ° C.
Or less, more preferably 40 ° C. or more and 100 ° C. or less, and the melting point is −20 ° C. or less, more preferably −40 ° C.
The following liquid media are preferably used. Generally, those having a low boiling point are difficult to handle because they evaporate immediately. In addition, it takes a very long time to completely volatilize a liquid medium having a boiling point exceeding 120 ° C. from the inside of the thin film. On the other hand, a liquid medium having a high melting point (freezing point), such as water, benzene, or cyclohexane, is not preferable because it tends to be solidified due to a temperature drop of the spray mist and makes it difficult to achieve the optimum spray conditions.

The liquid media satisfying the above conditions and recommended for practicing the present invention are those listed in Table 1 above. On the other hand, the liquid media listed in Table 2 above are not unusable, but are difficult to use because of too high a boiling point or too high a melting point. Particularly recommended liquid media are lower alcohols such as methanol, ethanol, and isopropyl alcohol, esters such as ethyl acetate and isopropyl acetate, ketones such as acetone and methyl ethyl ketone, chloroform, carbon tetrachloride, and 1,2-dichloroethane. Halogenated hydrocarbons, aromatic hydrocarbons such as toluene, aliphatic hydrocarbons such as n-pentane, n-hexane and n-heptane, nitrile compounds such as acetonitrile and propionitrile, amines such as triethylamine, and others, pyridine , Nitromethane, carbon disulfide and the like. These liquid media may be used alone or in a combination of two or more.

When the photofunctional organic compound to be used does not dissolve in these liquid media or has low solubility, it is preferable to use the compound in combination with a binder resin. in this case,
The binder resin is used as a solution and disperses the photofunctional organic compound. And it is sprayed as a dispersion liquid of a photofunctional organic compound.

The optimum concentration of the organic compound contained in the solution or dispersion to be sprayed, and the binder resin used as required, are determined by the thickness (target value) of the target organic thin film, the constituent components of the solution or dispersion, It depends on the size and structure of the equipment used, the shape of the spray nozzle used, the spray speed of the solution or dispersion, the nozzle heating temperature, and the heating conditions of the spray mist, so as to minimize the film formation time. Determined experimentally.

If the intended thickness of the organic thin film is intended to be as small as possible, the optimum concentration is often, for example, from 0.1 mg / ml to 0.01 mg / ml.
It is preferably smaller than. In order to obtain a film as thick as possible in a short time, the concentration may be increased.
However, if it is set too high, the trouble of nozzle blockage tends to occur. It depends strongly on the type of the organic compound used and the shape of the nozzle.
In the case of an organic dye having a high cohesiveness such as t-butyl copper phthalocyanine, the dye concentration in dichloromethane is 0.1 mg /
nozzle that could be used without any problem with a dye concentration of 0.2m
At g / ml, it clogged immediately after the start of spraying. When the same nozzle is used, for example, for an acetone solution of poly (benzyl methacrylate), the resin concentration is 1 mg / m 2.
Even if it was 1, it could be used without any problem. As is clear from the above examples, the optimum concentration of the organic compound contained in the solution or dispersion to be sprayed, and the binder resin used as necessary can be determined experimentally in consideration of the above conditions. Recommended.

When a binder resin is used, the concentration of the photofunctional organic compound is from 1 ppm to 99.9 wt% based on the weight of all organic compounds (photofunctional organic compound + binder resin) excluding the liquid medium. . The reason why the concentration range is so wide is that the types and functions of the photofunctional organic compounds are various. For example, the fluorescent dye is p
It is known that the function can be sufficiently exerted at a concentration on the order of pm.

Such a solution or dispersion is sprayed onto a substrate placed in a vacuum chamber, and information is recorded on the recording surface of the substrate on which pits and / or continuous grooves have been recorded. Is formed.

In practicing the present invention, mist or fine droplets sprayed from the spray nozzle into the vacuum chamber must be substantially free of liquid medium before reaching the substrate. In order to realize the “substantially liquid medium free state”, it is necessary to comprehensively control various conditions related to each other. Various conditions consist of physical constants and operating conditions.

The physical constants include (1) the latent heat of vaporization of the liquid medium, (2) the freezing point (melting point) temperature of the liquid medium, and
(3) It is necessary to consider the evaporation speed of the liquid medium from the mist in vacuum.

Regarding item (1), it is necessary to "substantially completely" compensate for the latent heat of vaporization of the liquid medium in the mist. Regarding the freezing point (melting point) temperature of the liquid medium in item (2), the latent heat of vaporization is removed from the mist in a vacuum, and when no heat is supplied, the liquid medium diverges from the time when the temperature of the mist reaches the freezing point temperature. Becomes extremely slow due to “sublimation”, and it is difficult to realize “substantially free of liquid medium” before reaching the substrate. Therefore, in order to realize the “substantially liquid medium free state”, it is necessary to control the mist temperature until reaching the substrate so as not to be lower than the melting point temperature of the liquid medium. Regarding item (3),
(I) The evaporation rate of the liquid medium from the mist in a vacuum depends on the size of the mist, and (ii) the pressure around the mist is different from the value of the “average pressure” inside the device because the liquid medium vapor fills up around the mist. It is necessary to take into account the complicated factors that evaporation from the mist occurs below, and (iii) the diffusion speed of the liquid medium vapor from around the mist is affected by the shape of the device, the pressure distribution, and the like. (Iv) There is also a troublesome problem that the values of the heat capacity and the heat of evaporation of the mist in a vacuum are not constant, and fluctuate with the temperature of the mist and the pressure around the mist.

On the other hand, as operating conditions, it is necessary to consider (4) nozzle heating temperature, (5) liquid spraying speed, (6) distance between nozzle and substrate, and (7) mist heating condition.

Regarding item (4), if the nozzle heating temperature is too high, the nozzle will be blocked. The spray speed of item (5) is the one that is most easily controlled. In practical terms,
In order to increase the film forming speed and, consequently, the productivity, it is preferable that the spraying speed is higher. Item (6) Since the nozzle-substrate distance is related to the design of the entire apparatus, the degree of freedom is low. Regarding item (7), there are various complicated related items such as light and infrared wavelengths for remotely heating the mist, light absorption characteristics of the mist, changes in the size of the mist, and changes in the heat capacity and latent heat of vaporization due to the temperature change of the mist. Conditions need to be considered. In any case, the heat of vaporization is supplied to the liquid medium in the mist placed in the vacuum by irradiating the mist sprayed from the spray nozzle with the rays and infrared rays in the band that the mist sprayed in the vacuum absorbs. Is done.

Here, the evaporation rate of the liquid medium from the mist discharged into the vacuum indicates a value specific to the apparatus used through the divergence rate of the liquid medium vapor generated around the mist. In order to increase the liquid medium evaporation rate to a practical rate, it is recommended to use (a) a liquid medium cooling trap and (b) a vacuum pump having a pumping speed as high as possible.
In particular, a liquid medium cooling trap cooled with liquid nitrogen is effective.

The nozzle heating temperature is experimentally optimum according to the type of the liquid medium used, the type and concentration of the photofunctional organic compound and / or the binder resin, the shape of the spray nozzle, and the spraying speed of the solution or dispersion. A value is required.
If the value is less than the optimum value, the spray speed cannot be increased. On the other hand, if the value exceeds the optimum value, the spray liquid dries at the nozzle and the nozzle is blocked. Needless to say, if the nozzle is not heated, the temperature may decrease due to the heat of evaporation, and the liquid medium may be solidified at the nozzle portion and the nozzle may be closed.

The nozzle-substrate distance K [m] is determined by the type of the spray solution, the nozzle shape, the nozzle heating temperature, the mist heating condition, and the solvent evaporation rate (average value) v [g / s] determined by the apparatus type. When the average weight w [g] of the droplet sprayed from the nozzle and the average flight speed L [m / s] of the droplet sprayed from the nozzle are used, the following equation is obtained.

[0055]

## EQU1 ## K = L.w / v

Actually, the value of v is not constant, and becomes slower as the solvent escapes from the droplet and the solid of the dye / resin precipitates in the droplet. Note that since it is a numerical value related to the weight of a volatile substance placed in a vacuum, it is extremely difficult to experimentally determine v and w. Further, in terms of device design, it is not easy to greatly change the distance between the nozzle and the substrate (for example, within a range of several tens of cm). It is about 10 cm to several cm that can be easily changed by attaching and detaching a flange and the like. In fact, for a particular device,
By adjusting the spraying speed, conditions under which the substrate is not damaged are experimentally obtained.

In order to completely remove the liquid medium from the mist, it takes a very long time because the deposited solids hinder the mass transfer of the liquid medium molecules. For example, P with a diameter of several μm
To completely remove volatile components from MMA particles, 10 ^-4
Heating to 100 ° C. or more under a vacuum of Pa requires several hours or more. Therefore, in order to achieve a practical spray rate (that is, a film forming rate), it is necessary to allow a solvent to remain in such a degree that the substrate is not damaged. This means "substantially free of the liquid medium".

In summary of the above items, (1) the latent heat of vaporization of the liquid medium and (2) the freezing point (melting point) temperature of the liquid medium are physical constants determined by the type of the liquid medium.
(3) The evaporation rate of the liquid medium from the mist depends on the size of the mist (depending on the device and operating conditions), the temperature of the mist (depending on the device and operating conditions), the heat capacity of the mist (depending on the temperature and pressure), the liquid It depends on the latent heat of vaporization of the medium (depending on the temperature), the equipment and the operating conditions described above and is measured experimentally. Items (4) to (7) of the operating conditions are interdependent, but are strongly governed by the size and configuration of the device and the configuration of the nozzle. The size of the apparatus to be used is determined by the size of the substrate and the number of films to be formed at one time. Next, when the configuration of the apparatus and the nozzle is determined, the distance between the nozzle and the substrate is substantially determined (as described above, several cm). It is easy to change the degree). next,
Mist heating conditions are determined (the heat that can be supplied to the mist is limited). When the above items are determined, the evaporation rate of the solvent can be experimentally determined according to the type of the liquid medium used, and finally, the “substantially liquid medium free state” is realized. The spray speed can be determined.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the drawings.

FIG. 1 is a schematic structural view showing an example of a vacuum film forming apparatus used for forming a thin film containing an optically functional organic compound on a substrate in an optical recording medium of the present invention. In the figure, a substrate support 12 having a rotating mechanism is provided in a vacuum chamber 10.
The substrate 14 is rotatably mounted on the substrate. Substrate 14
A spray nozzle 16 is provided on the wall of the vacuum chamber 10 opposite to the above, and a thin film forming material in a liquid state is sent from the pressurized liquid sending pump 18 to the spray nozzle 16. The temperature of the spray nozzle 16 is controlled by a spray nozzle heater (not shown). Further, by changing the position of the rotary shutter plate 41 by using the shutter plate rotation mechanism 42, the spray mist 44 from the spray nozzle 16 toward the substrate 14 can be temporarily shut off as necessary. . The light of the lamp 50 is transmitted through the window 51 attached to the wall of the vacuum chamber 10.
Irradiated toward the inside. The light emitted from the lamp 50 is a light ray and / or an infrared ray having a wavelength absorbed by the spray mist 44 and is a parallel light ray 55. The parallel light beam 55 from the lamp 50 is emitted so as to be substantially orthogonal to the flight direction of the spray mist 44 from the spray nozzle 16 toward the substrate 14. A liquid medium cooling trap 20 for capturing a vaporized liquid medium is provided at the rear of the substrate support table 12, and a turbo pump 22 and a vacuum pump 24 are provided downstream of the vacuum chamber 10 as an exhaust system. Has been established. As the vacuum pump 24 used as a preceding stage of the turbo pump 22, an oil rotary pump or a scroll pump is suitable.

FIG. 2 schematically shows a rotation mechanism of the substrate support 12. The substrate 14 is mounted so as to rotate integrally with the gear 30, and the gear 30 meshes with a gear 32 having a larger diameter than the gear 30. In this state, the arm 34 and the gears 30 and 32 respectively have a rotating shaft 34 b, 34a. When the arm 34 rotates about the rotation shaft 34a, the gear 30 rotates along the outer periphery of the gear 32 while rotating itself. Accordingly, the substrate 14 revolves around the gear 32 while rotating, and by depositing the organic compound on the substrate 14, the thickness of the formed thin film can be made uniform.

The vacuum film forming apparatus shown in FIGS. 1 and 2 will be described in further detail. First, after the inside of the vacuum chamber 10 is evacuated by the turbo pump 22 and the vacuum pump 24,
The liquid medium cooling trap 20 is cooled by a liquid nitrogen or helium circulation refrigerator (not shown) to a temperature lower than the melting point of the liquid medium to be used by 10 ° C. or more, for example, the boiling point of liquid nitrogen to −196 ° C. The melting point of the liquid medium is, for example, -95C for acetone and -97C for dichloromethane. If the temperature of the liquid medium cooling trap 20 is too close to the melting point of the liquid medium to be used, it becomes difficult to completely collect the vapor of the liquid medium evaporated from the spray mist. Further, since the surface of the liquid medium cooling trap 20 is gradually covered with the solidified liquid medium, the efficiency of the trap 20 gradually decreases. To compensate for this decrease in efficiency, it is preferable that the temperature of the trap 20 be as low as possible.

Needless to say, the trapping capacity of the trap 20 has an upper limit. When only one trap 20 is used, the film formation must be interrupted when the upper limit is reached. If necessary, it is preferable to provide a plurality of traps 20 and provide a mechanism that can be individually removed while keeping the vacuum state of the vacuum chamber 10. For example, when two traps are used, first, only the first trap is operated to trap the liquid medium, and then, when the surface of the first trap is completely covered with the solidified liquid medium, the second trap is activated. Put into operation, then remove the first trap and collect the liquid medium from the first trap. And
When the surface of the second trap is completely covered with the solidified liquid medium, by operating the first trap again, continuous film formation becomes possible.

Next, the thin film-forming material in a liquid state or a dispersed state containing the above-mentioned photofunctional organic compound and a binder resin used as necessary is fed under pressure by a pressure feed pump 18 and sprayed by a spray nozzle. Mist is sprayed into the vacuum chamber 10 in a high vacuum state from the spray nozzle 16 whose temperature is controlled by a heater (not shown). Thus, the temperature-controlled solution or dispersion is sprayed from the nozzle 16 into the vacuum chamber 10 as a mist 44.

The temperature of the solution or dispersion to be sprayed depends on the type of liquid medium used, the type and concentration of the photofunctional organic compound and / or the binder resin, the shape of the spray nozzle, the spray speed of the solution or dispersion. It must be controlled by a spray nozzle heater to be optimal. Although there is an optimum value for the nozzle heating temperature, there is a plurality of controlling factors, so it is necessary to experimentally set the temperature according to the use conditions. In order to promote the evaporation of the solvent from the sprayed mist, the higher the nozzle heating temperature, the better, but on the other hand, the high heating temperature tends to lead to the problem of nozzle blockage and, in the worst case, the thermal decomposition of organic compounds. . In order to prevent nozzle blockage, it is effective to set the nozzle heating temperature to a low temperature at the start of spraying and to gradually increase the temperature to an optimum value after the start of spraying. When using this technique, the temperature of the initially sprayed mist is lower than optimal and such mist must be prevented from depositing on the substrate. For this purpose, a rotary shutter plate 41 that temporarily blocks mist from the nozzle is used. At the start of spraying, the shutter plate 41 blocks the mist 44 from the nozzle 16 from reaching the substrate 14 and opens the shutter plate 41 for the first time after the nozzle heating temperature reaches the optimum value, thereby forming a preferable film. The condition, that is, “the condition that a thin film can be formed in a state substantially free of a liquid medium” can be achieved.

The spray speed of the solution or dispersion is adjusted to the above-mentioned optimum value by the pressurized liquid sending pump 18. further,
The pressure in the vacuum chamber 10 is adjusted by the evacuation system, that is, the evacuation speed of the turbo pump 22 and the vacuum pump 24.

Further, by adjusting the distance between the spray nozzle 16 and the substrate 14, the mist of the sprayed solution or dispersion scatters in the vacuum chamber 10 from the spray nozzle 16 to the substrate 14. In the meantime, it is possible to set so that most of the liquid medium is vaporized by being irradiated with light rays and infrared rays in a band absorbed by the mist. As a result, the photofunctional organic compound and / or binder resin substantially free of a liquid medium can be deposited on the substrate 14. Note that the vaporized liquid medium is captured by the trap 20.

The substrate 14 has a diameter of 40 mm to 300 m.
m and a liquid medium of the solution or dispersion having a boiling point at normal pressure of 30 ° C. or more and 120 ° C.
When a compound having a melting point of −20 ° C. or less and a melting point of −20 ° C. or less is used, a film forming condition for obtaining a thin film having a uniform thickness in “substantially free of a liquid medium” is to set the pressure in the vacuum chamber 10 The pressure is kept at 1 to 10 ^-6 Pa, the pumping speed from the vacuum chamber 10 is set to 50 liter / min to 100 cubic meters / min in terms of 1 atmosphere and 20 ° C., and the distance between the spray nozzle 16 and the substrate 14 is set to 1 to 10 times the substrate diameter. The temperature of the spray nozzle 16 is maintained at a temperature higher than the melting point of the liquid medium and at a temperature not higher than the boiling point at normal pressure, the temperature of the liquid trap is maintained at a temperature lower than the melting point of the liquid medium by 10 ° C. or more. This is achieved by spraying the liquid at a spray rate of 1 nanoliter / minute to 1 milliliter / minute.

Further, by irradiating the lamp 50 with light / infrared rays in a band that is absorbed by the mist sprayed in a vacuum, it is possible to more reliably achieve a “substantially solvent-free state”. By irradiating the mist sprayed in a vacuum with light rays or infrared rays, it is possible to supply the heat of evaporation of the liquid medium contained in the mist.

As the light source lamp 50, an ordinary tungsten light bulb or a halogen lamp is combined with a hyperbolic or elliptical cross-section reflecting mirror, and the light rays are almost parallel rays 55.
Is used. The cross-sectional shape of the parallel light beam 55 is not particularly limited, but will be described below as a parallel light beam having a circular cross section. The diameter of the circular cross section is preferably 0.5 to 5 times the diameter of the substrate. The irradiation direction of the parallel rays is different from the irradiation direction of the mist sprayed from the nozzle.
A direction that is generally orthogonal is optimal. 70 from orthogonal direction
It can be tilted about a degree. Even if the lamp 50 is installed inside the vacuum chamber 10, the lamp 50 is installed outside the vacuum chamber 10 and through a window 51 provided on the outer wall of the chamber.
The irradiation may be performed into the chamber.

The output of the lamp 50 is determined according to the photofunctional organic compound to be used and, when used, the light absorption characteristics of the binder resin in the ultraviolet, visible and infrared regions. When the photofunctional organic compound is a pigment and the diameter of the substrate is 40 mm to 120 mm, the capacity of the incandescent lamp is recommended to be 100 W to 500 W. When the diameter of the substrate is 120 mm to 300 mm, the capacity of the incandescent lamp is preferably 200 W to 2 kW. If the photofunctional organic compound used does not show absorption in the visible light region, an infrared lamp is used. The lamp output in such a case is preferably 2 to 10 times that in the above case where the incandescent lamp is applied to the dye. When the photofunctional compound to be used is sensitive to ultraviolet rays and causes a photodecomposition reaction or the like, an ultraviolet cut filter is used.

The state of heating by the lamp 50 can be monitored as follows. In other words, a thin thermocouple with a diameter of 0.1 to 0.2 mm at the tip is installed at a position where the spray mist does not adhere in the beam passage area inside the vacuum chamber to avoid the effect of heat conduction. The photofunctional compound to be used and, if used, a coating with a binder resin. The thickness of the coat layer is 1 to 200 μm. The temperature indicated by the thermocouple when the lamp 50 is turned on corresponds to the temperature reached when the lamp heating is continued to the mist after the solvent has completely evaporated, and from this temperature, the amount of heat received by the spray mist is estimated. be able to. If the photofunctional compound used is prone to thermal decomposition, this system can avoid lamp irradiation that exceeds the energy required for evaporation of the solvent.

After completion of the spraying of the solution or the dispersion, the substrate 14
The substrate 14 is heated in order to completely remove volatile components such as a liquid medium remaining in the upper thin film.

When a thermoplastic resin is used as the substrate and / or the binder resin, the above-mentioned heating temperature must not exceed the thermal deformation starting temperature of the thermoplastic resin. At the same time, the melting point and the thermal decomposition onset temperature of the used photofunctional organic compound must not be exceeded. When the photofunctional organic compound used is sublimable, the temperature must not exceed the temperature at which violent sublimation starts.

When the substrate and the binder resin are not thermoplastic, the melting point and the thermal decomposition onset temperature of the used photofunctional organic compound must not be exceeded. When the photofunctional organic compound used is sublimable, the temperature must not exceed the temperature at which violent sublimation starts.

In any of the above cases, when the photofunctional organic compound and / or the binder resin used cause an irreversible phase change or crystal type change, the starting temperature must not be exceeded.

For example, if the substrate material is polycarbonate,
When forming only a film of a low molecular weight organic compound without using a binder resin, the heat treatment is performed at 40 ° C. to 80 ° C. for 1 minute to 2 minutes.
Time is enough.

Further, when a binder resin is used, 4
It takes 24 to 48 hours at 0 ° C and 1 to 8 hours at 80 ° C.

The thickness of the thin film formed by the above steps depends on the type of the optical recording medium, but is from 10 nm to 2000 n.
m.

Further, a reflective film made of, for example, aluminum may be formed on the thin film formed in the above steps by a vacuum evaporation method and laminated. Further, for example, a protective layer made of an ultraviolet curable resin may be formed and laminated according to a known method.

[0081]

The present invention will be described more specifically with reference to the following examples.

<Example 1> As cyanine dyes,
3,3,1 ', 3', 3'-hexamethyl-2,2'-
(4,5,4 ′, 5′-Dibenzo) indodicarbocyanine perchlorate was dissolved in acetone to prepare a 1% by weight solution. The above dye solution was applied to a polycarbonate resin injection-molded substrate on which an EFM signal having a density approximately four times that of a normal compact disk was formed as minute pits (shortest pit length: 0.4 μm, pit depth: 80 nm). Using the vacuum film forming apparatus shown in FIG. 2, a dye thin film having a thickness of about 250 nm was formed. During spraying,
Parallel light 55 from a 300 W halogen lamp 50 equipped with a parabolic reflecting mirror having an opening of 60 mm in diameter.
Was irradiated from a window 51 provided on the outer wall of the vacuum chamber 10 in a direction orthogonal to the spray direction from the nozzle 16. During irradiation of the lamp, the surface was 10 μm thick with the cyanine dye.
The heating temperature measured by a thermocouple coated on the substrate was 150 ° C., which was lower than the thermal decomposition starting temperature of the dye.

The other vacuum film forming conditions at this time were as follows.

(1) Vacuum chamber internal pressure: 1 × 10 ⁻⁴ Pa (2) Dye solution spray rate: 100 μl / min (3) Vacuum chamber pumping rate: 450 l / min (1 atm, converted to 20 ° C.) 4) Distance between spray nozzle and substrate: 180 mm (5) Heating temperature of spray nozzle: 40 ° C. After forming a thin film containing a cyanine dye on a substrate,
The substrate was heated at about 60 ° C. for 1 hour.

Thereafter, a scanning electron microscope (SEM)
Observation of the pits on the substrate surface confirmed that the pits were not filled even after the formation of the dye thin film, as shown in FIG.

Comparative Example 1 The same cyanine dye as in Example 1 was dissolved in ethyl cellosolve to prepare a solution having a concentration of 3% by weight. Next, the film was applied on a polycarbonate resin injection-formed substrate on which the same pits as used in Example 1 were formed by a spin coating method, and the film thickness was about 300 n.
m of the dye thin film was formed. When the pits on the substrate surface were observed by SEM in the same manner as described above, it was confirmed that the pits after the formation of the dye thin film were filled with the dye, as shown in FIG.

Example 2 A super-resolution optical disk was manufactured by forming a mask layer having a thermochromic compound as a reversible dye on a substrate. That is, a fluoranthene compound as an electron donating color compound and bisphenol A as a color developer were dissolved in acetone at a molar ratio of 1: 3 to prepare a mixed solution having a concentration of 1% by weight.

An EFM signal having a density approximately four times that of a normal compact disk is composed of minute pits (the shortest pit length is 0.4 μm,
The above dye solution is applied to a polycarbonate resin injection molded substrate having a pit depth of 80 nm) by using the vacuum film forming apparatus shown in FIGS.
A mask layer made of a 0 nm dye thin film was formed. During spraying, parallel rays from a 250 W infrared lamp equipped with a parabolic reflecting mirror having a diameter of 120 mm at the opening were irradiated from a window provided on the outer wall of the vacuum chamber in a direction perpendicular to the nozzle spray direction. During the lamp irradiation, the heating temperature measured by a thermocouple whose surface was coated with the solid content of the spray liquid to a thickness of 200 μm was 120 ° C., which was lower than the thermal decomposition starting temperature of each of the organic compounds used.

At this time, the other vacuum film forming conditions were as shown below.

(1) Vacuum chamber internal pressure: 1 × 10 ⁻⁴ Pa (2) Dye solution spray rate: 360 μl / min (3) Vacuum chamber evacuation rate: 450 l / min (1 atm, converted to 20 ° C.) 4) Distance between the spray nozzle and the substrate: 180 mm (5) Heating temperature of the spray nozzle: 40 ° C. Further, on the mask layer, aluminum is formed as a reflective layer to a thickness of about 70 nm by a vacuum sputtering method. A UV-curable resin Seika Beam VDAL-392 (manufactured by Dainichi Seika Kogyo) was formed as a protective layer to a thickness of about 7 μm to obtain a super-resolution optical disk.

This super-resolution optical disk was manufactured at a wavelength of 680 nm.
Reproduced by a player equipped with a semiconductor laser. In this case, the numerical aperture of the pickup lens (N
A) is 0.6, and linear velocity (CLV) is 3 m /
s, and the reproduction power was about 3.0 mW.

Due to the super-resolution of the reproduced signal waveform (eye pattern) of the reproduced disk, the ratio of the 3T signal amplitude to the 11T signal amplitude was 82.2% as shown by the oscilloscope waveform of FIG. It was confirmed that the frequency characteristics were excellent.

Comparative Example 2 The fluoranthene compound used in Example 2 was mixed with bisphenol A in a molar ratio of 1: 3.
Was dissolved in acetone to prepare a mixed solution having a concentration of 4% by weight.

Then, a polycarbonate resin injection-formed substrate having the same pits as used in Example 2 was applied by a spin coating method to a film thickness of about 700 n.
m of the dye thin film was formed. Further, a reflective film and a protective film were formed on the dye thin film in the same manner as in Example 2 to obtain an optical disk.

[0095] Reproduction of the obtained optical disk was attempted using the same player as in Example 2, but reproduction was impossible because the thermochromic material filled the pits on the substrate.

As described above, according to the present invention, even when a polycarbonate resin having a relatively low resistance to a liquid medium is used as the substrate, the substrate is not damaged by the liquid medium and the pits are not filled. A thin film containing the compound can be formed. Further, there is an advantage that a cyanine dye which cannot be formed by a heating vacuum evaporation method because it does not exhibit sublimability can be easily formed into a film.

[0097]

According to the method for manufacturing an optical recording medium of the present invention, small pits and shallow grooves already formed on a substrate are not filled and the pits and grooves are not damaged. A thin film layer containing a photofunctional organic compound can be formed. That is, by the method of the present invention, a condition that a thin film can be formed in a substantially liquid medium free state is achieved, and a solution or a dispersion liquid sprayed on the substrate may flow or attack the substrate. A thin film layer containing a photofunctional organic compound can be formed on a substrate without the liquid medium coming into direct contact with the substrate.

Further, in the optical recording medium of the present invention, since fine pits and grooves formed in advance on the substrate are not filled with the layer containing the organic compound, high-density recording or reproduction becomes possible. .

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an example of a configuration of a vacuum film forming apparatus used for manufacturing an optical recording medium of the present invention.

FIG. 2 is a schematic configuration diagram for explaining a rotation mechanism of a substrate support in the vacuum film forming apparatus of FIG.

FIG. 3 is a scanning electron microscope photograph taken on the surface of the optical recording medium obtained in Example 1 so that the shape of a pit can be seen.

FIG. 4 is a scanning electron micrograph of the surface of the optical recording medium obtained in Comparative Example 1 taken so that the shape of a pit can be seen.

FIG. 5 is an oscilloscope-type photograph of an eye pattern of a reproduction signal of an optical recording medium obtained in Example 2.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Vacuum chamber, 12 Substrate support with a rotation mechanism, 14 Substrates, 16 Spray nozzle, 18 Pressure liquid feed pump, 20 Liquid medium cooling trap, 22 Turbo pump, 24 Vacuum pump, 30, 32 Gear, 34 Arm, 34a, 34b rotating shaft, 41 rotating shutter plate, 42 shutter plate rotating mechanism, 44 spray mist,
50 lamps, 51 windows, 55 parallel rays.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shigeru Takarada 1-9-4 Horinouchi, Adachi-ku, Tokyo Dainichi Seika Kogyo Co., Ltd. Tokyo Manufacturing Office (72) Inventor Hiromitsu Yanagimoto 1-chome Horinouchi, Adachi-ku, Tokyo No. 9-4 Dainichi Seika Kogyo Co., Ltd. Tokyo Manufacturing Office (72) Inventor Ichiro Ueno 3-12 Moriyacho, Kanagawa-ku, Yokohama-shi, Kanagawa Japan Victor Company of Japan, Ltd. (72) Inventor Koji Tsujita Kanagawa 3-12 Moriyacho, Kanagawa-ku, Yokohama-shi Victor Company of Japan, Ltd.

Claims (11)

[Claims] 1. A liquid medium-free state using a substrate on which information is previously recorded as pits and / or continuous grooves on at least one recording surface, so as not to impair the shape of the pits and / or continuous grooves. Spraying a solution or dispersion of a film-forming material containing at least one type of photofunctional organic compound onto at least one recording surface of the substrate placed in a vacuum chamber. A method for producing an optical recording medium, further comprising heating and drying the thin film. 2. The method of manufacturing an optical recording medium according to claim 1, wherein the mist of the solution or dispersion of the film-forming material sprayed into a vacuum chamber has a wavelength band that the mist absorbs and / or light. A film forming method comprising supplying heat of evaporation of a liquid medium in a mist by irradiating a heat ray. 3. The method for manufacturing an optical recording medium according to claim 1, wherein the film-forming material consists essentially of at least one kind of the optically functional organic compound. Production method. 4. The method for manufacturing an optical recording medium according to claim 1, wherein the film-forming material consists essentially of a mixture of at least one kind of the optically functional organic compound and a binder resin. Manufacturing method of an optical recording medium. 5. The method for producing an optical recording medium according to claim 1, wherein a disk having a diameter of 40 mm to 300 mm is used as the substrate, and the solution or the dispersion liquid has a boiling point of 30 at normal pressure. ℃ to 120 ℃, melting point -20 ℃
Using the following compounds, the film forming conditions were as follows: the pressure in the vacuum chamber was maintained at 1 to 10 ⁻⁶ Pa, and the evacuation speed from the vacuum chamber was 50 liter / min to 100 cubic meters / min in terms of 1 atmosphere and 20 ° C. The distance between the spray nozzle and the substrate is 1 to 10 times the diameter of the substrate, the temperature of the spray nozzle is maintained at a temperature higher than the melting point of the liquid medium and at a temperature equal to or lower than the boiling point at normal pressure, 10 ° C above the melting point of the liquid medium
A method for producing an optical recording medium, comprising: spraying the solution or dispersion at a spray rate of 1 nanoliter / minute to 1 milliliter / minute. 6. The method for manufacturing an optical recording medium according to claim 5, wherein the liquid trap is cooled by liquid nitrogen. 7. The method for manufacturing an optical recording medium according to claim 1, wherein a substrate made of a thermoplastic resin is used as the substrate, and the heating and drying temperature of the thin film is set to a temperature at which thermal deformation of the thermoplastic resin starts. A method for producing an optical recording medium, wherein the temperature is not exceeded. 8. The method for manufacturing an optical recording medium according to claim 1, further comprising forming a reflective film and a protective film on said thin film. 9. An optical recording medium manufactured by the method for manufacturing an optical recording medium according to claim 1. 10. The optical recording medium according to claim 9, wherein said substrate has optical transparency. 11. The optical recording medium according to claim 9, wherein said substrate is formed of a thermoplastic resin.