WO2004005040A1

WO2004005040A1 - Phase change type optical recording medium and process for producing the same

Info

Publication number: WO2004005040A1
Application number: PCT/JP2003/008364
Authority: WO
Inventors: Hiroyuki Mochizuki; Toshiko Mizokuro; Takashi Hiraga; Norio Tanaka
Original assignee: National Institute Of Advanced Industrial Science And Technology
Priority date: 2002-07-02
Filing date: 2003-07-01
Publication date: 2004-01-15
Also published as: JP2004034453A; AU2003246175A1; JP3862164B2

Abstract

A phase change type optical recording medium having a uniform thickness of recording layer and capable of high-density recording by radiation of widely ranging wavelength; and a process for producing the same. In particular, a phase change type optical recording medium produced through steps of providing an optical recording layer comprised at least of a crystalline organic polymeric compound in amorphous form and causing an organic low-molecular compound capable of penetrating from the surface of the optical recording layer comprised of a crystalline organic polymeric compound toward the internal portion thereof in the form of gaseous molecules to act on the optical recording layer so that the crystalline organic polymeric compound undergoes a phase change from amorphous form to crystal form. Information is recorded by the utilization of phase change from crystal form to amorphous form of the crystalline organic polymeric compound of the phase change type optical recording layer which is induced by ultraviolet, visible light or infrared rays radiated from outside. The record is reproduced by the utilization of change of optical properties accompanying the phase change.

Description

Description Phase change optical recording medium and method for manufacturing the same

The present invention relates to a phase-change optical recording medium and a method for manufacturing the same, and more particularly, to a phase-change optical recording medium having a uniform thickness of a recording film and capable of performing high-density recording with light of a wide range of wavelengths. It relates to the manufacturing method. Background art

The optical recording medium is a read-only type (ROM) that reproduces recorded information, a write-once type (WO RM) that can be recorded only once, and an erasable type that can be erased and re-recorded after recording. (Rew ritab 1 e). A method of arranging a light source and a reading device with a transmission-type optical recording medium sandwiched in between Since the driving mechanism of the light source and the reading device becomes complicated, a light source is provided by providing a reflective layer in the optical recording medium. And the reading device are installed on the same side of the optical recording medium. Currently, the mainstream optical recording media are required to have a reflectance of 70% or more and a CN ratio of 47 dB or more (CarireoNoiseRatio).

In an optical recording medium on which information is recorded, information can be reproduced by changing the reflectivity of the recording layer before and after recording due to physical deformation, phase change, magnetic property change, etc. . Further, in addition to the above-described high reflectance and high CN ratio characteristics, long-term storage stability and high recording sensitivity are required. Since the development of the optical recording medium, much research has been conducted to satisfy the above-mentioned requirements and to improve the required characteristics.

Japanese Patent Application Laid-Open No. 63-2681842 discloses a method of forming a sensitive layer on a substrate by vapor deposition of components such as gelatin, casein and polyvinyl alcohol, and an optical recording of a structure formed on the sensitive layer. A medium is disclosed. According to such an optical recording medium, recording pits are formed by the metal thin film absorbing a laser beam used for recording and deforming the sensitive layer and the metal thin film. However, this recording pit is exposed type It is difficult to keep records for a long period of time.

U.S. Pat. No. 4,983,440 describes an optical recording medium in which a recording layer having a two-layer structure composed of a metal thin film and a protective layer for protecting the recording layer are sequentially laminated on a substrate. It has been disclosed. However, in this optical recording medium, the metal thin film cannot sufficiently serve as a reflection layer, the reflectance is as low as 20% or less, and there is no compatibility with CD. In an optical recording medium, information is recorded not by a recording method based on expansion and deformation of a substrate but by decomposition of a substrate material. Therefore, as the material of the metal film, a metal that generates high heat enough to decompose the substrate is used. However, since the deformation due to the formation of the recording pit is limited to the metal layer itself, the CN ratio characteristics are not good.

U.S. Pat.No. 5,073,219 discloses that a metal, such as aluminum, gold, or copper, or an alloy thereof is vapor-deposited on the entire surface of a substrate to form a conductive film, which includes a liquid crystal and a dichroic dye. A method for manufacturing an optical recording medium through a process of forming a layer and then orienting a liquid crystal and a dichroic hue by corona discharge, a magnetic field or shear stress is disclosed. Such an optical recording medium uses a principle in which information is recorded according to a difference in reflectance due to a change in the orientation of the liquid crystal and the dichroic dye due to condensed light. However, the difference in reflectance between the group and the land is small, and the tracking conditions are very complicated. As a result, the reflectivity of the recording portion decreases.

In a write-once type recording medium using a dye, the recording layer, which is the most important part, is generally formed by spin-coating a coating solution comprising a solvent and a dye on a substrate. However, the recording layer formed by such a process has a problem that it is difficult to obtain uniform optical characteristics. That is, the recording layer is formed by spin-coating a coating solution on a substrate made of PC, methyl polymethacrylate, cellulose acetate, acrylic resin, etc., and its optical characteristics are determined by the uniformity and thickness of the coated film. Depends on. Here, factors affecting the film thickness of the recording layer include the concentration of the spin coating liquid, the rotation speed and acceleration of the coating apparatus, the coating time, the flow rate of the coating liquid, and the dose time. It is not easy to properly adjust them, and it is also very difficult to adjust the viscosity that actually affects the film thickness.

In addition, the organic solvent of the coating solution for forming the recording layer includes the base of the optical recording medium. It is necessary to use a material that does not attack the plate, but such a solvent has a problem in that the ability to dissolve the dye is weak and the types of dyes that can be used are limited. Further, when the main component of the recording layer is composed of a dye, the signal is formed by thermal deformation of the dye and the substrate, so that it is difficult to finely adjust the magnitude of the signal during high-density recording. U.S. Pat. No. 5,328,813 discloses that a flexible metal thin film is formed as a recording layer on a substrate, and a hard metal oxide layer is formed thereon to enhance the recording preservation property and improve the reflection stability. It is disclosed that the ratio is increased to 40 to 60%. However, there is a problem that as the reflectance increases, the CN ratio decreases. This makes it difficult to manufacture optical recording media having high reflectivity and high CN ratio. Disclosure of the invention

An object of the present invention is to provide a phase-change optical recording medium having a uniform thickness of a recording film and capable of performing high-density recording with light of a wide range of wavelengths, and a method for manufacturing the same.

In order to achieve the above object, the present invention provides at least a light-transmitting support and an optical recording layer, wherein the optical recording layer is made of at least a crystalline organic polymer compound, Alternatively, information is recorded by utilizing a phase change from a crystalline state to an amorphous state of the crystalline organic polymer compound in the optical recording layer, which is induced by infrared rays, and information of optical properties accompanying the phase change is recorded. A phase change type optical recording medium characterized in that the recording is reproduced by utilizing a change. The phase change type optical recording medium of the present invention may have a light reflection layer.

In order to achieve the above-mentioned object, the present invention provides at least an optical recording layer made of the crystalline organic polymer compound in an amorphous state, and a surface of the optical recording layer made of the crystalline organic polymer compound. Phase changing the crystalline organic high molecular compound from an amorphous state to a crystalline state by causing a low molecular weight organic compound capable of penetrating from inside to the inside as a gas molecule. Provided is a method for manufacturing a type optical recording medium. BRIEF DESCRIPTION OF THE FIGURES FIG. 1 is a cross-sectional view showing the configuration of the optical recording medium of the present invention.

FIG. 2 is a cross-sectional view schematically showing an optical waveguide manufacturing apparatus in the optical recording medium manufacturing method described in Examples 1 and 2 of the present invention.

FIG. 3 is a cross-sectional view schematically illustrating an optical waveguide manufacturing apparatus in the optical recording medium manufacturing method according to the third and fourth embodiments of the present invention.

FIG. 4 is a cross-sectional view schematically showing an optical waveguide manufacturing apparatus in the optical recording medium manufacturing method according to the fifth embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

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

In the present invention, a polycarbonate resin represented by the following general formula (I) is preferably used as the crystalline organic polymer compound.

Position [over _{0 - φ Α - X - φ} Β - Ο- 0 (= 0) _one] η - ... (I)

(Here, _beta [Phi _Alpha and φ represent each a divalent aromatic hydrocarbon residue, X represents an oxygen ZanKiichi o-, sulfur residues - S-, sulfonate residues> S = 〇, Karupokishi remaining Group> C = O or an alkylene hydrocarbon residue> represents CR i R ² , wherein R ¹ and R ² are a hydrogen atom or an alkyl group having 1 to 18 carbon atoms which may have a substituent. Wherein R ¹ and R ² may combine with each other to form a hydrocarbon ring.)

Polycarbonate resin (hereinafter abbreviated as “PC”) is a linear polymer having an ester carbonate bond O—R—O—CO— in the main chain, and has good dimensional stability and transparency. In particular, it has excellent impact resistance. Used for various molded products, especially engineering plastics and films. PC is widely used as a transparent support for optical recording media utilizing the above properties. We found that by applying the vapor of the low molecular weight compound to the PC, only the surface of the PC exposed to the vapor of the low molecular weight compound crystallized. PC crystallization can occur even when a liquid of an organic low-molecular compound is directly applied to PC, but it is not easy to control the progress of crystallization, especially the progress of uniform crystallization at each position on the surface. . That is, it is preferable that the organic low molecular weight compound is sublimated or evaporated under atmospheric pressure or reduced pressure to form a gas and then act on the PC surface. Also, by raising the temperature of the PC, Can be accelerated.

As a result of various experiments in which the type of organic low-molecular compound acting on PC was changed, it was found that the molecular size of the organic low-molecular compound and the free volume of PC are closely related to the progress of crystallization of PC. all right. In other words, if the organic low molecular weight compound is a good solvent that dissolves PC, it cannot exhibit crystallization.On the other hand, it penetrates into free space without dissolving PC and produces lubricity between PC main chains. It has been found that a low molecular weight organic compound having a molecular volume that allows the crystallization of PC to proceed smoothly.

When the PC is placed in a closed container with controllable pressure and temperature and the vapor of the organic low molecular weight compound is allowed to act, the lower limit of the temperature is the glass transition of the composition composed of the organic low molecular weight compound penetrating into the PC. Temperature, and the upper limit of the temperature is the melting point of the composition. At these temperatures, the pressure in the container must be equal to or lower than the saturated vapor pressure of the low-molecular organic compound.

The crystallization of Pc proceeds from the surface to the inside of the optical recording layer due to the permeation of the organic low molecular weight compound. The degree of progress from the surface, that is, the thickness of the crystallized PC, can be controlled by the exposure time, temperature and pressure of the organic low-molecular compound gas, and the thickness is 1 to 200 nm when used as an optical recording medium. Is required, and it is preferably 10 to 100 nm. The thickness of the crystallized layer depends on gas molecules, but when exposed to 2,2'-diphenylpropane, when the temperature is 100 to 120 ° C and the pressure is 10 to ⁴ Pascal or less, Achieved with an exposure time of 10 to 60 minutes.

When the optical recording medium of the present invention is of a transmission type in which signal light (probe light) passes through the optical recording medium, the most basic structure is constituted by crystallizing the surface of an amorphous PC. A configuration called “light-transmitting support (amorphous PC) Z optical recording layer (crystalline PC)” may be mentioned. Further, a protective film, an antioxidant film, an overcoat film, and the like may be appropriately added to the basic structure.

In the case of the reflection type, in which signal light (probe light) is transmitted through an optical recording medium and then reflected to detect reflected light, the most basic structure is a light-transmitting support (amorphous PC) / optical recording layer

(Crystalline PC) A Z light reflection layer is exemplified. Further, a protective film, an antioxidant film, an overcoat film, and the like are appropriately added to the basic structure. The light reflecting layer may be made of aluminum, aluminum-chromium alloy, aluminum-titanium alloy, silver, gold, etc. Metals having high reflectivity are preferable, and the light reflecting film made of these metals is formed by a vapor deposition method or a sputtering method.

The PC used in the present invention has the chemical formula represented by the above (I), and preferably has an alkylene-type hydrocarbon residue, and RR ² is methyl and methyl, methyl and ethyl, and methyl and ethyl, respectively. It is. Also! ^ ¹ ^ ^2: ¹ and R ² are bonded, may for example those to form a cyclohexane ring. More specifically, (Bisphenol-A.polycarbonate in which R ¹ and R ² are methyl groups can be suitably used.)

Organic polymer compounds that can be stably present in both crystalline and amorphous forms include polycarbonate resins, aromatic dicarboxylic acids such as terephthalic acid, and dihydric alcohols such as ethylene dalicol. Polyester, for example, polyethylene terephthalate can be mentioned.

1 (a) and 1 (b) are cross-sectional views schematically showing the basic structure of the optical recording medium of the present invention. As shown in FIG. 1A, in the case of the transmission type, a crystallized PC layer 20 is present on a PC substrate 10, and an overcoat layer 30 is provided thereon. Further, as shown in FIG. 1 (b), in the case of the reflection type, a crystallized PC layer 21 is present on the PC substrate 11 as in the case of the transmission type, and a reflection film 41 is provided thereon. An overcoat layer 31 is provided thereon.

The light source used for recording and reading on the phase-change optical recording medium of the present invention is not particularly limited, but it is preferable to use a laser beam in order to increase the recording density to the diffraction limit of light. Further, as an advantage of the present invention, any of ultraviolet light, visible light, and infrared light can be suitably used as long as the wavelength of the light source is light having a wavelength that transmits amorphous PC. As is well known, amorphous PC exhibits a transmittance of 80% or more to light of 350 nm or more, so that light of 350 nm or more is suitable. If the recording medium disperses the dye, the absorption wavelength of the dye is 350 nm or more.If the medium does not disperse the dye, the near-infrared to infrared light (600 to 1000 nm), which easily changes to heat, is more preferable. .

Recording on the phase-change optical recording medium of the present invention is performed as follows. That is, the recording focused on the crystallized PC layer in the optical recording layer provided on the PC substrate. When the writing light (laser light) is irradiated, the temperature of the light irradiated part rises due to multiple reflection and scattering by the crystallized PC. Here, if the power of the recording / writing light and the irradiation time are sufficient, the temperature of the light-irradiated portion rises above the melting point of PC, then drops to room temperature, and in the process, the crystallized portion becomes amorphous. , Be transparent. This transparent amorphous portion becomes a pit representing recording. As the reading light for recording, low-power light is used such that the temperature rise in the light-irradiated portion is far below the melting point of the PC. Here, if the recording / reading light is polarized and adjusted so that the light receiving section of the reading light can correctly receive the polarized light, the CN ratio can be increased even with low power light. When the configuration of the optical recording medium is a transmission type, the readout light transmitted through the transparent pit is transmitted. When the configuration of the optical recording medium is a reflection type, the readout light is transmitted through the transparent pit. The recording pits can be detected by receiving the read light reflected by the reflection layer. Here, if the light for reading the recording pits raises the temperature of the non-recording part, that is, the crystallized part of the PC, and may exceed the melting point of the PC, the recording pit is broken. Such an undesired situation may be caused when the same portion of the optical recording medium is repeatedly read (for example, when a “still image” is extracted from an optical recording medium on which a moving image has been recorded). In order to prevent the recording pit from being destroyed by the reading light, the reading light power should be 1 Z 2 or less, preferably 1 Z, below the minimum value of the light (recording / writing light) power required for optical recording. 5 or less, more preferably 1 Z 10 or less.

Examples of the method for manufacturing the optical recording medium of the present invention include, for example, the following four manufacturing methods.

(1) Injection molding of PC, transfer land & group pattern from stamper to the surface at this time, so that the surface of PC is vaporized by organic low-molecular compound vapor by the method of the present invention so as not to mess up the pattern. Process and crystallize. After that, in the case of the reflection type, for example, an aluminum light reflection layer is formed by a sputtering method, and further in the case of the transmission type, on the crystallized PC layer, and in the case of the reflection type, on the light reflection layer. The protective layer is formed by coating with an ultraviolet curable resin to produce a desired optical recording medium.

(2) Transfer the land & group pattern from the stamper to the surface during PC injection molding. In order not to break the pattern, the method of the present invention Is treated with the vapor of an organic low-molecular compound to crystallize. After that, the surface of the PC is treated with a vapor of a sublimable dye having an affinity for PC instead of the organic low molecular weight compound (dye impregnation treatment). In the case of a reflection type, an aluminum light reflection layer is formed by sputtering. . Next, as described above, the protective layer is coated and formed with an ultraviolet curable resin on the crystallized PC layer in the case of the transmission type, and on the light reflection layer in the case of the reflection type, and the desired optical recording medium is formed. Make it.

(3) PC is injection molded, and the land & group pattern is transferred from the stamper to the surface. The surface of the PC is treated (dye-impregnated) with a vapor of a sublimable dye having an affinity for PC so as not to break the pattern, and the surface is colored. Crystallizes the surface of the PC. Then, in the case of the reflection type, an aluminum light reflection layer is formed by sputtering, and in the case of the transmission type, on the crystallized PC layer, in the case of the reflection type, on the light reflection layer, and in the case of the reflection type, the protective layer is made of ultraviolet light. A desired optical recording medium is produced by coating with a cured resin.

(4) After injection molding the PC and transferring the land and groove pattern from the stamper to the surface, the surface of the PC is formed of a colored organic low-molecular compound (dye) by the method of the present invention so as not to swell the pattern. It is treated with steam to crystallize the PC surface layer simultaneously with coloring. Thereafter, an aluminum light reflecting layer is formed by sputtering in the case of the reflection type, and on the crystallized PC layer in the case of the transmission type, and on the light reflection layer in the case of the reflection type, as described above. Then, the protective layer is coated and formed with an ultraviolet curable resin to produce a desired optical recording medium. Here, as a colored organic low-molecular-weight compound that can simultaneously color the PC surface layer, for example, 2-methyl-4,12-throaline (yellow) can be used.

Specific examples of organic low-molecular compounds that crystallize amorphous PC include alcohol-based compounds, and more specifically, linear or branched compounds having 8 or less carbon atoms. Alcohols are mentioned, preferably, methanol, ethanol, n-propyl alcohol, 2-propyl alcohol and n-butanol. Similarly, ketones include linear or branched ketones having 8 or less carbon atoms, preferably acetone, methylethylketone, getylketone, methylpropylketone. Tons. Similarly, examples of cellosolves include linear or branched cellosolves having 8 or less carbon atoms, preferably methoxyethanol and ethoxyethanol. Similarly, examples of the ester system include a linear or branched ester having 8 or less carbon atoms, preferably ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, propyl propionate and the like. . Similarly, examples of the organic acid system include a linear or branched organic acid having 8 or less carbon atoms, and formic acid, acetic acid, propionic acid, and butanoic acid are preferable. Further, similarly, examples of the aromatic organic low-molecular compound include those having no straight-chain alkyl having 8 or more carbon atoms or branched alkyl having 12 or more carbon atoms as a substituent. Preferably, benzene, quinone, hydroquinone, bipheninole, 2-methinolebiphenyl, 3-methinolebiphenyl, 4-methinolebiphenyl, naphthalene, 1-methinolenaphthalene, 2-methylnaphthalene, and 3-methyl Naphthalene, 4-methylnaphthalene, 2,2-dipheninolepropane, 2,2-dipheninolebutane, 3,3-dipheninolepentane, bithiophene, 2-methinolevitione, 3-methinolebitiophen, 4-1 Methylbithiophene, 2,2,1-biviridine, 3-methyl_2,2, -biviridine, 4-methyl-2,2,1-biviridine, 5-methyl-1,2,2'-viviridine, 6-methyl-1,2, 2, Bibiridin, benzofuran, benzothiazole, benzoxazole, indene, indanone, benzquinone, quinoline, Oren, such as force carbazole, and the like.

Examples of the colored organic low-molecular compound (dye) include dyes of cyanine type, phthalocyanine type, quinone type, sulfur type, azurenium type, thiol complex salt type, merocyanine type and the like.

It was also found that when a vapor of methyl ditroaline was applied to PC, the PC was colored yellow and crystallized at the same time. As a specific example of methylnitroaniline, 2-methyl-4-nitroaniline ゃ 4-methinole-13-toroaniline can be suitably used.

Needless to say, the optical recording layer made of PC crystallized and simultaneously crystallized with a colored organic low-molecular compound writes recording pits efficiently with recording light having a light absorption wavelength of the organic compound (dye). be able to. In addition, the wavelength of the reading light is By setting the wavelength different from the light absorption wavelength of the organic compound (dye) and using different wavelengths of the recording light and the reading light, the possibility of destruction of the recording pit due to reading can be extremely reduced. Example

[Example 1]

FIG. 2 is a cross-sectional view illustrating a schematic configuration of an optical recording medium manufacturing apparatus used in this example. Using a stamper, a PC board 300 with a thickness of 1.20 mm, an outer diameter of 120 mm, and an inner diameter of 15 mm having a guide groove (group) with a depth of 80 nm, a width of 500 nm, and a pitch of 1600 nm was manufactured. On the other hand, a vaporization source 240 (urethane sponge, eg, 5 mm thick, 10 mm wide, 400 mm long) was prepared by impregnating 2,2-diphenylpropane as a low-molecular organic compound into a porous sponge. The PC board 300 is provided in a closed container 110, and the vaporization source 240 is provided in another closed container 120. The two sealed containers 110 and 120 are connected by a pipe and pulp 195. Here, the outer wall of the sealed container 110 on which the PC board 300 is installed is made of stainless steel or aluminum, and has a structure (not shown) that can be vertically divided for taking in and out the board.

The inside 100 of the sealed container 110 is connected to a vacuum exhaust system 150 via a vacuum pulp 190 and a vacuum piping system 130. Then, when producing the optical recording medium, the vacuum pulp 190 is closed after evacuation is performed at room temperature (25 ° C.) until the pressure inside the sealed container 110 becomes 10-4 Pascal or less. Thereby, the closed container 110 is closed.

As the vaporization source substrate heater 410, the resin substrate heater 400, and the vacuum pulp heater 790 used as heating means, for example, those made of aluminum in which a sheathed electric heating wire of a vacuum specification is embedded can be used. By installing a heater made of a material having high heat conductivity without gaps, the inside 100 of the closed container 110 and the portion of the vacuum pulp 190 can be uniformly heated.

In the case of the present embodiment, the interior 100 of the sealed container 110 is evacuated using a vacuum pulp 190, and then the vacuum pulp 190 is closed. The temperature was controlled so that the whole temperature was 90 ° C. Also, the sealed container 120 in which the vaporization source 240 is placed and sealed is heated using the vaporization source substrate heater 410 in the same manner, and the temperature is set according to the set temperature of the sealed container 110 in which the PC board 300 is installed. Was also heated to a high temperature (eg, 100 ° C). Thereafter, the pulp 195 connecting the two closed containers 110, 120 was opened and kept at the set temperature for 8 hours. After that, the internal temperature of the closed vessels 110 and 120 was gradually lowered to 25 ° C. Next, the inside 100 of the sealed container 110 was returned to the atmospheric pressure, and the PC substrate 300 was taken out. As a result of observing a cross section of the obtained PC substrate 300 with a scanning microscope, it was confirmed that the PC substrate 300 was crystallized from the surface to a depth of 10 nm and that the group was not deformed. Next, a reflective layer (reflective film) was formed on aluminum by vapor deposition on the recording layer thus obtained. Further, a protective layer (overcoat layer) of 5 μπι was provided thereon from an ultraviolet curable resin to produce a desired optical disk. The reflectivity of this optical recording medium is 73%, and as a result of recording an EFM-CD format signal at a linear velocity of 1.4 m / sec using a semiconductor laser with a wavelength of 785 nm, the optimal recording laser power is 1 OmW. Recording was possible. Next, this signal was reproduced by a CD player with a laser power of 0.5 mW. As a result, the CN ratio of the obtained signal was good.

[Comparative Example 1]

As in Example 1, a reflective layer of aluminum was formed by vapor deposition on a PC substrate having grooves formed by a stamper, and a protective layer was formed of an ultraviolet curable resin. I tried to record an EFM-CD format signal on this optical disc at a linear velocity of 1.4 m / sec using a semiconductor laser with a wavelength of 785 nm, but found that nothing could be recorded.

[Example 2]

A PC substrate was produced in the same manner as in Example 1, and biphenyl was used as an organic low-molecular compound for crystallizing the surface. The temperature of the inside 100 and the crystallization time of the inside of the sealed container 110 during the crystallization process of PC are 100 ° C and 12 hours, respectively. The sealed container 120 on which 240 is placed is also heated in the same manner, except that it is heated to a temperature higher than the set temperature of the sealed container 110 on which the PC board 300 is placed (for example, 110 ° C). The other steps were the same as in Example 1. As a result, EFM-CD format signals could be recorded. When the obtained optical recording medium was reproduced by a CD player, the CN ratio of the signals was good.

[Example 3]

FIG. 3 is a cross-sectional view illustrating a schematic configuration of an optical recording medium manufacturing apparatus used in the present example. Using a stamper, a PC board 301 with a thickness of 1.20 mm, an outer diameter of 120 mm, and an inner diameter of 15 mm with a guide groove (group) having a depth of 80 nm, a width of 500 nm, and a pitch of 1600 nm was produced. On the other hand, a vaporization source 241 (urethane sponge, for example, 5 mm thick, 10 mm wide, 400 mm long) was prepared by impregnating a low-molecular organic compound (2,2-diphenyl lip pan) with a porous sponge. The PC board 301 is installed in a closed container 111, and the vaporization source 241 is installed in another closed container 121. These two closed containers 111 and 121 are connected by a pipe and pulp 196. Here, the outer wall of the sealed container 111 on which the PC board 301 is installed is made of stainless steel or aluminum, and has a structure (not shown) that can be divided into upper and lower parts for taking in and out of the board.

The inside 101 of the sealed container 1 1 1 is connected to a vacuum exhaust system 151 via a vacuum valve 191 and a vacuum piping system 131. Evacuate until the pressure in the chamber falls below 10_4 Pascal, and then close the vacuum valve 191. As a result, the closed container 111 is closed.

As the vaporization source substrate heater 411, the resin substrate heater 401, and the vacuum valve heater 791 used as heating means, for example, those made of aluminum in which a sheathed electric heating wire of a vacuum specification is embedded can be used. By installing a heater made of a material having high heat conductivity without gaps, the inside 101 of the closed container 111 and the portion of the vacuum pulp 191 can be uniformly heated.

In the case of this embodiment, the valves 196 and 197 are closed, the vacuum pulp 191 is opened, and the valves are closed. After depressurizing the inside 101 of the closed container 111, the vacuum pulp 191 was closed, and then heated by a resin substrate heater 401 to control the temperature so that the entire temperature reached 90 ° C. Similarly, the sealed container 121 in which the vaporization source 241 is placed and sealed is heated using the vaporization source substrate heater 411, and the set temperature of the sealed container 1 1 1 in which the PC board 301 is placed is set. (Eg, 100 ° C.). After that, the pulp 196 connecting the two closed containers 1 1 1 and 1 1 2 was opened and kept at the set temperature for 8 hours. Thereafter, the pulp 196 was closed, while the vacuum pulp 191 was opened, and the inside 101 of the sealed container 111 was evacuated again. Then, the valve 197 was opened, and the resin substrate heater 401 was used to obtain D. The temperature of the container 140 containing isperse B 1 ue 14 (1,4-bis (N-methylamino) anthraquinone) and the temperature of the sealed container 111 were gradually increased to 145 ° C and maintained for 2 hours. Next, the valve 197 was closed, the inside 101 of the sealed container 111 was returned to the atmospheric pressure, and the PC board 301 was taken out. Observation of the cross section of the obtained PC substrate 301 with a scanning microscope showed that Disperse Blue 14 (1,4-bis (Ν-methylamino) anthraquinone) had penetrated into the crystallized portion. , I confirmed that the group was not deformed. Next, aluminum as a reflection layer was formed on the recording layer thus obtained by vapor deposition. Further, a protective layer of 5 μπι was formed thereon from an ultraviolet-curable resin to produce a desired optical disk. The reflectivity of this optical recording medium is 73%, and as a result of recording an EFM-CD format signal at a linear velocity of 1.4 m / sec using a semiconductor laser with a wavelength of 785 nm, the optimum recording laser power is 1 OmW Could be recorded. Next, this signal was reproduced with a laser power of 0.5 mW using a CD player, and the CN ratio of the obtained signal was good.

[Example 4]

FIG. 3 is a cross-sectional view showing a schematic configuration of the optical waveguide manufacturing apparatus used in this embodiment, similarly to the third embodiment. Using a stamper, a PC board 301 with a thickness of 1.20 mm, an outer diameter of 120 mm, and an inner diameter of 15 mm with guide grooves (group) 80 nm deep, 500 nm wide and 1600 nm pitch was fabricated. On the other hand, organic low molecular compounds (2, 2— A vapor source 24 1 (urethane sponge, for example, 5 mm thick, 10 mm wide, 400 mm long) in which diphenylpropane) was impregnated into a porous sponge was prepared. The PC board 301 is set in a closed container 1 1 1, and the vaporization source 2 41 is set in another closed container 1 2 1. The two closed containers 1 1 1 and 1 2 1 are connected by piping and pulp 196. Here, the outer wall of the hermetically sealed container 111 on which the PC board 301 is installed is made of stainless steel or aluminum, and has a structure (not shown) that can be vertically divided for inserting and removing the board.

The interior 101 of the sealed container 1 1 1 is connected to the vacuum exhaust system 1 5 1 via the vacuum valve 1 9 1 and the vacuum piping system 1 3 1. Then, at the time of producing the optical recording medium, the inside of the sealed container 111 was evacuated at room temperature until the pressure inside the sealed container 110 became 10-4 Pa or less, and then the vacuum pulp 191 was closed. As a result, the closed container 1 1 1 is hermetically closed.

The vaporization source substrate heater 4 11, the resin substrate heater 4 0 1, and the vacuum pulp heater 7 9 1 used as heating means can be, for example, those made of aluminum in which a sheathed electric heating wire of a vacuum specification is embedded. . By installing a heater made of a material having high heat conductivity without gaps, the inside of the closed vessel 111 and the portion of the vacuum valve 91 can be uniformly heated.

In the case of this embodiment, the pulp 196 is first closed and the pulp 197 is opened. Next, open the vacuum valve 191, and open the inside of the sealed container 1 1 1 1 and the container 1 4 containing the Disperse Blue 14 (1,4-bis (N-methylamino) anthraquinone). After reducing the pressure of 0, the vacuum pulp 1 9 1 is closed, and then heating is performed by a resin substrate heater 4 0 1, so that the inside of the sealed container 1 1 1 and the inside of the container 1 The temperature was controlled to 5 ° C., and the temperature was maintained for 2 hours. Next, after closing the tube 197, the vacuum pulp 191 was opened, and the inside 101 of the sealed container 111 was evacuated again. After that, the vacuum pulp 191 is closed, the temperature of the PC board 301 and the inside 101 of the sealed container 111 are lowered to 90 ° C, while the vaporization source 241 is placed and sealed. The closed container 1 2 1 is heated using the vaporization source substrate heater 4 1 1 and is heated to a temperature higher than the set temperature of the closed container 1 1 1 in which the PC board 301 is installed (for example, 1 0 0 ° C). Then connect the two closed containers 1 1 1 and 1 2 1 Pulp 196 was opened and held at the set temperature for 8 hours. Next, the pulp 196 was closed, the inside 101 of the closed container 111 was returned to atmospheric pressure, and the PC substrate 301 was taken out. Observation of the cross section of the obtained PC substrate 301 with a scanning electron microscope showed that Disperse Blue 14 (1,4-bis (N-methylamino) anthraquinone) had penetrated into the crystallized portion. And it was confirmed that the group was not deformed. Next, aluminum as a reflective layer was formed on the recording layer thus obtained by vapor deposition. Further, a protective layer of 5 μm was formed from an ultraviolet-curable resin on this, and a desired optical disk was manufactured. The reflectivity of this optical recording medium is 71%. As a result of recording an EFM-CD format signal at a linear velocity of 1.4 m / sec using a semiconductor laser with a wavelength of 785 nm, the optimum recording laser power is 1 Recording was possible with OmW. Next, this signal was reproduced by a CD player with a laser power of 0.5 mW, and the CN ratio of the obtained signal was good.

[Example 5]

FIG. 4 is a cross-sectional view showing a schematic configuration of an optical waveguide manufacturing apparatus used in this example. Using a stamper, a PC substrate 302 having a thickness of 1.20 mm, an outer diameter of 120 mm, and an inner diameter of 15 mm having a guide groove (group) having a depth of 80 nm, a width of 500 nm, and a pitch of 1600 nm was produced. On the other hand, a vaporization source 242 equipped with an organic low molecular weight compound (4-methyl-3-nitro-2-arin) was prepared. The PC board 302 is provided in a closed container 112, and the vaporization source 242 is provided in another closed container 122. The two closed containers 1 1, 1 2 and 2 are connected by piping and pulp 198. The outer wall of the sealed container 112 on which the PC board 302 is installed is made of stainless steel or aluminum, and has a structure (not shown) that can be vertically divided for taking in and out the board.

The inside 102 of the sealed container 112 is connected to a vacuum exhaust system 152 via a vacuum pulp 192 and a vacuum piping system 132. Then, at the time of producing the optical recording medium, the vacuum pulp 192 was closed after evacuation was performed at room temperature until the pressure in the inside 102 of the sealed container 112 became 10-4 Pascal or less. Thereby, the closed container 112 is closed. The vaporization source substrate heater 4 12, the resin substrate heater 402 and the vacuum pulp heater 7 92 2 used as a heating means can be made of, for example, aluminum in which a sheathed electric heating wire of a vacuum specification is embedded. . By installing a heater made of a material having high heat conductivity without gaps, the inside 102 of the closed container 112 and the portion of the vacuum pulp 192 can be uniformly heated.

In the case of this embodiment, after opening the vacuum pulp 192 and reducing the pressure 102 inside the closed vessel 112, the vacuum pulp 192 is closed, followed by heating by the resin substrate heater 402 and sealing. Temperature control was performed so that the entire inside of the type container 112 was kept at 135 ° C. Similarly, the sealed container 1 2 2 in which the vaporization source 2 42 is placed and hermetically sealed is also heated using the vaporization source substrate heater 4 1 2, and the hermetically sealed container in which the PC substrate 302 is installed The container was heated to a temperature higher than the set temperature of the container 112 (for example, 140 ° C.). After that, the pulp 198 connecting the two closed vessels 112, 122 was opened and kept at the set temperature for 12 hours. After that, the internal temperature of the sealed containers 1 12 and 122 was gradually reduced to 25. Then, the inside 102 of the closed container 112 was returned to the atmospheric pressure, and the PC substrate 302 was taken out. As a result of observing the cross section of the obtained PC substrate 302 with a scanning microscope, it was confirmed that yellow crystallized from the surface to a depth of 10 nm and that the tube was not deformed. Next, aluminum as a reflection layer was formed on the recording layer thus obtained by vapor deposition. Further, a protective layer of 5 / m was provided thereon with a UV-curable resin to produce a desired optical disk. The reflectivity of this optical recording medium is 73%. As a result of recording an EFM-CD format signal at a linear velocity of 1.4 m / sec using a semiconductor laser with a wavelength of 785 nm, the optimum recording laser power However, recording was possible at 1 O mW. Next, this signal was reproduced by a CD player with a laser power of 0.5 mW, and as a result, the CN ratio of the obtained signal was good.

As described in detail above, since the optical recording medium of the present invention has a crystalline PC having a recording layer function on a transparent substrate, a complicated process is not required, and extremely high recording storability and good An optical recording medium having a high CN ratio can be provided. Although the present invention has been described in detail, the scope of the present invention is not limited to the above description. Industrial applicability

Can be used as a phase-change optical recording medium capable of high-density recording with light of a wide range of wavelengths. In addition, a read-only type (ROM) that reproduces recorded information, recording can be performed only once It can be used as various types of optical recording media such as write-once type (WORM) and rewritable type that can be erased and re-recorded after recording. .

Claims

The scope of the claims

1. having at least a light-transmitting support and an optical recording layer,

Further, the optical recording layer has a crystallization layer made of at least a crystalline organic polymer compound in a crystalline state,

Information is stored in the optical recording layer by utilizing the fact that the crystalline organic polymer compound of the crystallized layer undergoes a phase change from a crystalline state to an amorphous state by irradiation of any one of ultraviolet light, visible light and infrared light from outside. Wherein the information recorded in the optical recording layer is reproduced by utilizing the change in optical properties accompanying the phase change.

2. The phase according to claim 1, further comprising a light reflection layer formed on a surface of the optical recording layer opposite to a surface of the optical recording layer to which reading light is applied during reproduction. A changeable optical recording medium.

3. The phase-change optical recording medium according to claim 1, wherein a polycarbonate resin represented by the following general formula (I) is used as the crystalline organic polymer compound. .

One _{[- O - φ Α - X} - ΦΒ- Ο- C (= Ο) _one] η - ... (I)

(Here, phi _Alpha and phi _beta represent each a divalent aromatic hydrocarbon residue, X represents an oxygen ZanKiichi o-, sulfur residues - S-, sulfonate residues> s = o, Karupokishi remaining group> C == O or represents an alkylene hydrocarbon residue! ^ ^1! ^ ^2, R ¹ and R ² represents an alkyl group having 1 to 8 hydrogen atom or a C 1 -C, R ¹ and R ² includes those bonded to each other to form a hydrocarbon ring.)

4. The phase-change type optical recording medium according to claim 1, wherein the crystallization layer in the optical recording layer contains a dye that absorbs any one of ultraviolet light, visible light, and infrared light.

5. At least an optical low-molecular compound that can penetrate from the surface of the optical recording layer to the inside thereof acts as gas molecules on the optical recording layer made of a crystalline organic polymer compound in an amorphous state, Forming a crystallized layer in the optical recording layer by changing at least a part of the crystalline organic polymer compound in the layer from an amorphous state to a crystalline state. Manufacturing method of recording medium.

6. The method for producing a phase-change optical recording medium according to claim 5, wherein the organic low-molecular compound is colored.

7. At least an optical recording layer made of a crystalline organic polymer compound in an amorphous state is allowed to act as a gas molecule with an organic low molecular compound that can penetrate from the surface of the optical recording layer to the inside thereof, Forming a crystallized layer in the optical recording layer by changing at least a part of the crystalline organic polymer compound in the layer from an amorphous state to a crystalline state,

A dye that has an affinity for the crystalline organic polymer compound, has sublimability, and absorbs any one of ultraviolet, visible or infrared light as gas molecules from the surface of the optical recording layer to the inside; A method for producing a phase-change optical recording medium, comprising the steps of: infiltrating into a crystallized layer in the optical recording layer;

8. At least the optical recording layer made of the crystalline organic polymer compound in the non-crystalline state has an affinity for the crystalline organic polymer compound, and is a sublimable dye, such as ultraviolet light, visible light or Forming a dye layer in the optical recording layer by infiltrating a dye that absorbs infrared rays as gas molecules from the surface of the optical recording layer into the interior thereof; and forming the amorphous organic polymer compound in an amorphous state. An organic low molecular compound that can penetrate from the surface of the optical recording layer into the inside thereof acts on the optical recording layer as gas molecules, and the crystalline organic polymer compound in the dye layer of the optical recording layer is in an amorphous state. Forming a dye-containing crystallized layer by changing the phase from a crystalline state to a crystalline state. A method for producing a phase-change type optical recording medium, comprising: