JP3886889B2 - Magneto-optical recording medium and method for producing magneto-optical recording medium - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a magneto-optical recording medium in which a mark having a predetermined size, which is magnetized in a direction corresponding to the supplied magnetic field, is continuously formed in a predetermined direction, and such a magneto-optical recording The present invention relates to a method for manufacturing a medium.
[0002]
[Prior art]
Conventionally, magneto-optical recording media such as magneto-optical disks that record information using both light and magnetism have been widely used. The magneto-optical recording medium includes a magnetic layer having magnetism. In the magneto-optical recording medium, information is recorded by forming a series of marks representing information on the magnetic layer. That is, in order to record information on the magneto-optical recording medium, the magneto-optical recording medium is irradiated with a recording light beam and supplied with a magnetic field, and this magnetic layer is magnetized in a direction corresponding to the supplied magnetic field. A mark is formed. In addition, in order to reproduce information recorded on the magneto-optical recording medium, the magneto-optical recording medium is irradiated with a reproducing light beam, and the mark formed on the magnetic layer is read out.
[0003]
In recent years, a further improvement in recording density has been demanded for such a magneto-optical recording medium. In order to improve the recording density of the magneto-optical recording medium, a high-precision reproduction technique for accurately reproducing information recorded at a high density is required in addition to a technique for realizing high-density recording.
[0004]
In order to realize high-density recording, it is desired that the magnetic layer of the magneto-optical recording medium has low noise and high holding power. Patent Document 1 proposes that a nonmagnetic metal film is formed as an underlayer of the magnetic layer, and that the magnetic layer has a low noise and a high holding power by the action of the nonmagnetic metal film. In addition, it is desired to increase the coercive force for short marks by making the magnetic domain cluster, which is the minimum recording unit of the magnetic layer, as small as possible. When a fine concavo-convex pattern is provided on the underlayer of the magnetic layer, the concavo-convex pattern is reflected in the magnetic layer, and a magnetic domain cluster is formed in the magnetic layer for each portion corresponding to the convex portion. Therefore, it is preferable to provide the underlying layer with as fine a concave / convex pattern as possible, and conventionally, a base layer is known in which spherical particles having a minute particle size are spread. In this underlayer, a fine concavo-convex pattern is formed by the upper half portions of the particles adjacent to each other.
[0005]
On the other hand, in order to realize high-precision reproduction, a reproduction layer is provided on a magnetic layer for recording information, and a domain wall displacement detection (DWDD) in which a magnetic wall is moved in the reproduction layer during reproduction, or a reproduction layer during reproduction. A technique such as MAMMOS (Magnetic Amplifying Magneto-Optical System) for expanding the magnetic domain is known.
[0006]
[Patent Document 1]
Japanese Patent Laid-Open No. 2001-291230
[Problems to be solved by the invention]
Here, considering that a base layer in which spherical particles are spread is provided on a magneto-optical recording medium to which a technique such as DWDD or MAMMOS is applied, even if particles with a small particle size are used, It is considered that the hemispherical shape of the upper half part is reflected to the reproducing layer, and magnetic domain clusters are also formed in the reproducing layer. If a magnetic domain cluster is formed in the reproducing layer, movement of the domain wall and expansion of the magnetic domain during reproduction are hindered.
[0008]
In view of the above circumstances, the present invention provides a magneto-optical recording medium provided with an underlayer on which a fine concavo-convex pattern that does not affect the reproducing layer is formed, and a method for manufacturing such a magneto-optical recording medium. Objective.
[0009]
[Means for Solving the Problems]
The magneto-optical recording medium of the present invention that achieves the above object is a magneto-optical recording medium in which marks of a predetermined size magnetized in a direction corresponding to the supplied magnetic field are continuously formed in a predetermined direction. In the recording medium,
A substrate,
A particle layer provided on the substrate and having a particle size smaller than the size of the mark and having a plane on the surface forming the external shape, the particle layer arranged in the predetermined direction with the plane facing upward,
A recording layer provided on the fine particle layer, on which the mark is formed;
A reproducing layer provided on the recording layer and magnetized in the same direction as the magnetization direction of the mark formed on the recording layer and having a region larger than the size of the mark. .
[0010]
According to the magneto-optical recording medium of the present invention, the fine particle layer becomes an underlayer of the recording layer. On the surface of the fine particle layer, a fine concavo-convex pattern is formed in which the flat surface of the particle is the protruding surface of the convex portion, and in the recording layer, magnetic domain clusters are formed for each portion corresponding to the convex portion. Yes. For this reason, high-density recording can be realized. Further, the fine concavo-convex pattern formed on the underlayer is not reflected in the reproduction layer because the protruding surface of the convex portion is flat, and the reproduction layer becomes a flat layer. As a result, the domain wall is moved and the magnetic domain is enlarged smoothly during reproduction in the reproducing layer.
[0011]
In the magneto-optical recording medium of the present invention, the particles preferably have a particle size of 10 nm or less.
[0012]
If it is 10 nm or less, a sufficiently fine uneven pattern is formed in the underlayer, and a sufficiently fine magnetic domain cluster is formed in the recording layer.
[0013]
Furthermore, in the magneto-optical recording medium of the present invention, an intermediate layer having a Curie temperature lower than the Curie temperature of both the recording layer and the reproducing layer is formed between the recording layer and the reproducing layer. It is also preferable.
[0014]
By providing such an intermediate layer, the magnetization of the intermediate layer can be lost at a temperature lower than the temperature at which the magnetization of the recording layer and the magnetization of the reproducing layer disappear. When the temperature of the intermediate layer is lower than the Curie temperature of the intermediate layer, exchange coupling with the recording layer acts on the intermediate layer, and the reproducing layer has a magnetization direction of a mark formed on the recording layer. Is formed in the same direction as the mark, but if the temperature of the intermediate layer exceeds the Curie temperature, the magnetization of the intermediate layer disappears and the recording layer The exchange coupling is broken, and a region larger than the size of the mark magnetized in the same direction as the magnetization direction of the mark is formed in the reproducing layer.
[0015]
In the method of manufacturing a magneto-optical recording medium of the present invention that achieves the above object, a magnetic field is supplied, and marks of a predetermined size magnetized in a direction corresponding to the supplied magnetic field are continuously formed in a predetermined direction. In the manufacturing method of the magneto-optical recording medium,
By reducing a solution obtained by adding a polymer material to a solution in which predetermined particles are dissolved, the particle size is smaller than the size of the mark, and the surface forming the external shape has a flat surface. A coating liquid production process for producing a coating liquid in which particles whose surfaces are coated with the polymer material are dispersed;
A coating liquid produced by the coating liquid production process is applied onto a substrate, and a fine particle layer in which particles dispersed in the coating liquid are arranged in the predetermined direction with the flat surface facing upward on the substrate. A fine particle layer forming step to be provided;
A recording layer forming step of providing a recording layer on which the mark is formed on the fine particle layer provided by the fine particle layer forming step;
A reproduction layer in which a region larger than the size of the mark is formed on the recording layer provided by the recording layer forming step is magnetized in the same direction as the magnetization direction of the mark formed on the recording layer. And a layer forming step.
[0016]
According to the method for manufacturing a magneto-optical recording medium of the present invention, the magneto-optical recording medium of the present invention can be manufactured. In addition, in the coating liquid manufacturing step, the surface forming the external shape of the particles is coated with the polymer material, so that the particles do not stick to each other in the coating liquid, and in the fine particle layer forming step, the particles are A fine particle layer uniformly arranged in a predetermined direction can be formed.
[0017]
In the method for manufacturing a magneto-optical recording medium of the present invention, the recording layer and the reproducing layer are formed on the recording layer after the recording layer forming step and before the reproducing layer forming step. It is preferable to have an intermediate layer forming step of providing an intermediate layer having a Curie temperature lower than both of the Curie temperatures.
[0018]
Furthermore, in the method for manufacturing a magneto-optical recording medium of the present invention, if the particles contain metal atoms, the coating liquid can be easily manufactured in the coating liquid manufacturing step.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described.
[0020]
A magneto-optical recording medium according to an embodiment of the present invention is a so-called DWDD medium including a recording layer having lands and grooves formed on the surface thereof.
[0021]
FIG. 1 is a schematic cross-sectional view of the magneto-optical recording medium according to the present embodiment, taken along the groove extending direction.
[0022]
A magneto-optical recording medium 1 shown in FIG. 1 has a fine particle layer 11, a recording layer 12, an intermediate layer 13, a reproducing layer (moving layer) 14, and a protective layer 15 laminated in this order from the substrate 10 side. . The substrate 10 shown in FIG. 1 is a polycarbonate disk, but it may be a glass substrate or a photopolymer film transferred to a glass substrate.
[0023]
The fine particle layer 11 is a layer in which Pt fine particles 111 are arranged on the surface of the support layer 110 in the groove extending direction. The Pt fine particles 111 are particles having a hexahedral structure with a particle size of 10 nm. Each surface of the Pt particles 111 is a flat surface, and the Pt fine particles 111 are arranged on the surface of the support layer 110 with one of the surfaces facing upward. A slight gap of less than 10 nm is formed between adjacent Pt fine particles 111, and a fine uneven pattern is formed on the surface of the support layer 110 by the surface facing upward of the Pt fine particles 111 and this gap. Has been. In addition, not only Pt fine particles but fine particles containing metal atoms such as Au may be used. The particle diameter of the fine particles may be 10 nm or less, and the structure of the fine particles is not limited to the hexahedral structure, and may be a polyhedral structure.
[0024]
The recording layer 12 is a TbFeCo film having a thickness of 60 nm. The TbFeCo film is a magnetic film having easy magnetic domains in the vertical direction. In the recording layer 12, magnetic domain clusters are formed for each portion corresponding to the convex portions of the fine concavo-convex pattern provided in the fine particle layer 11, and the size of the formed magnetic domain clusters 121 is very small. In the magneto-optical recording medium 1 shown in FIG. 1, information is recorded by forming a series of marks representing information in the groove of the recording layer 12. That is, in order to record information on the magneto-optical recording medium 1, a recording light beam is irradiated and a magnetic field is supplied while the magneto-optical recording medium 1 is rotated, and the recording layer 12 is heated by the light beam irradiation. The coercive force is lowered, and marks magnetized in the direction corresponding to the supplied magnetic field are continuously formed in the groove of the recording layer 12. Since the magnetic domain cluster 121 of the recording layer 12 is very small, even if the length of the groove extending direction (hereinafter referred to as a mark length) is short, the mark can be firmly held.
[0025]
The intermediate layer 13 is a TbFe film having a thickness of 10 nm. The Curie temperature of the intermediate layer 13 is 150 ° C. The Curie temperature of the recording layer 12 is 260 ° C., and the Curie temperature of the reproducing layer 14 is 280 ° C. Therefore, the intermediate layer 13 is a layer having a Curie temperature lower than the Curie temperature of the recording layer 12 and lower than the Curie temperature of the reproducing layer 14.
[0026]
The reproduction layer 14 is a GdFeCo film having a thickness of 30 nm. In order to read the recorded information from the magneto-optical recording medium 1, the reproducing optical beam is irradiated while the magneto-optical recording medium 1 is rotated. The recording layer 12, the intermediate layer 13, and the reproducing layer 14 are heated by irradiation with the reproducing light beam. Until the temperature of the intermediate layer 13 reaches 150 ° C. which is the Curie temperature of the intermediate layer 13, exchange coupling with the recording layer 12 acts on the intermediate layer 13, and the reproducing layer 14 is formed on the recording layer 12. A region that is magnetized in the same direction as the magnetization direction of the mark and has the same size as the mark is formed. When the temperature of the intermediate layer 13 becomes 150 ° C. or higher by irradiation with the light beam, the magnetization of the intermediate layer 13 disappears and exchange coupling with the recording layer 12 is broken, and the reproducing layer 14 is formed on the recording layer 12. A region that is magnetized in the same direction as the magnetization direction of the mark and that is larger than the size of the mark is formed. That is, a temperature gradient is formed in the reproducing layer 14 heated by irradiation with the light beam, the domain wall in the reproducing layer 14 moves to the high temperature side, and the same direction as the magnetization direction of the mark formed in the recording layer 12. A region larger than the size of the mark is formed. The protective layer 15 is a SiN dielectric film having a function of protecting the recording layer and the like from moisture and the like.
[0027]
Next, a method for manufacturing the magneto-optical recording medium 1 of the present embodiment will be described.
[0028]
FIG. 2 is a flowchart showing each step in manufacturing the magneto-optical recording medium shown in FIG.
[0029]
As shown in FIG. 2, in manufacturing the magneto-optical recording medium 1 shown in FIG. 1, the coating liquid manufacturing process 51, the fine particle layer forming process 52, the recording layer forming process 53, the intermediate layer forming process 54, and the reproduction layer forming process are performed. 55 and the protective layer forming step 56 are carried out in this order of description.
[0030]
In the coating liquid production step 51, 0.2 ml of a polymer solution to which 0.1 mol of polyvinylpyrrolidone (PVP) is added is mixed with 250 ml of an aqueous solution to which 0.1 mmol of K ₂ PtCl ₄ is added. Next, the mixed solution is put in a predetermined container, and after flowing argon gas for 20 minutes, hydrogen gas is flowed for 5 minutes, and the container is sealed and refluxed for 12 hours. That is, slow hydrogen reduction is performed. By doing so, a coating liquid in which Pt fine particles 111 having a hexahedral structure with a particle size of 10 nm are dispersed is obtained. The Pt fine particles in the coating solution are covered with a polymer material and are uniformly dispersed without sticking to each other.
[0031]
Note that an aqueous solution to which H ₂ PtCl ₆ is added may be used instead of the aqueous solution to which K ₂ PtCl ₄ is added, and a high concentration of sodium polyacrylate (PAA) added to the polymer solution to which polyvinyl pyrrolidone is added. A molecular solution may be used. Further, alcohol reduction using methanol or ethanol may be performed instead of hydrogen reduction.
[0032]
In the fine particle layer forming step 52, the coating solution obtained in the coating solution manufacturing step 51 is applied onto the substrate 10 shown in FIG. 1 by a spin coating method.
[0033]
FIG. 3 is a diagram schematically showing a substrate on which a coating solution has been applied by spin coating.
[0034]
A support layer 110 is provided on the substrate 10 in advance, and the coating liquid 2 is applied to the surface 110 a of the support layer 110. Here, first, the coating liquid 2 is dropped on the surface 110a of the support layer 110 while rotating the substrate 10 at a rotation speed of 10 rpm, and then the rotation speed is increased to 100 rpm. As the rotation speed increases, the coating liquid 2 spreads uniformly over the entire surface 110 a of the support layer 110. Thereby, the Pt fine particles 111 in the coating liquid are uniformly dispersed over the entire surface 110a of the support layer 110 without overlapping each other. Thereafter, the coating liquid 2 is naturally dried.
[0035]
FIG. 4 is a diagram schematically showing the substrate after the coating liquid has been naturally dried.
[0036]
A fine particle layer 11 is formed on the substrate 10 shown in FIG. The Pt fine particles 111 in the applied coating solution are arranged on the surface 100a of the support layer 110 in the groove extending direction with any one surface facing upward. By performing natural drying, the coating liquid is vaporized leaving the Pt fine particles 111, and a slight gap S is generated between the Pt fine particles 111 adjacent to each other. On the surface 110 a of the support layer 110, a fine uneven pattern is formed by the surface 111 a facing upward of the Pt fine particles 111 and the gap S.
[0037]
In the recording layer forming step 53, the recording layer is formed so that the surface of the fine particle layer 11 thus formed, that is, the back surface is in contact with the fine uneven pattern. In this step, the recording layer 12 shown in FIG. 1 is formed by magnetron sputtering under the conditions of a gas pressure of 1.0 Pa and an input power of 0.5 kW.
[0038]
In the intermediate layer forming step 54, the intermediate layer 13 is formed so that the back surface is in contact with the surface of the recording layer 12. In the reproducing layer forming step 55, the reproducing layer 14 is formed so that the back surface is in contact with the surface of the intermediate layer 12. To do. In any process, sputtering film formation is performed under the condition of a gas pressure of 0.5 Pa. In the protective layer forming step 56, the protective layer 15 shown in FIG. 1 is formed by sputtering.
[0039]
Next, experimental results will be described. In this experiment, by adjusting the spot size of the recording light beam, the mark length of the mark formed on the recording layer 12 of the magneto-optical recording medium 1 shown in FIG. 1 is changed, and information is recorded with a different mark length. did. Then, for each magneto-optical recording medium recorded with different mark lengths, signal intensity (carrier) and noise at the time of reproduction were measured, and CNR (Carrier to Noise Ratio) was obtained.
[0040]
FIG. 5 is a graph showing the mark length dependence of CNR in the magneto-optical recording medium shown in FIG.
[0041]
In the graph shown in FIG. 5, the horizontal axis represents the mark length (unit: μm), and the vertical axis represents CNR (unit: dB). Here, for comparison, the sample in which the fine particle layer is omitted from the magneto-optical recording medium 1 shown in FIG. 1 and the fine particle layer 12 of the magneto-optical recording medium 1 shown in FIG. 1 are replaced with a fine particle layer in which spherical particles are arranged. Two samples were prepared and information was recorded with different mark lengths to obtain CNR. The line connecting the circular plots shown in FIG. 5 represents the result in the magneto-optical recording medium shown in FIG. 1, and the line connecting the triangular plots represents the result in the sample having the fine particle layer in which spherical particles are arranged. The line connecting the square plots represents the result in the sample without the fine particle layer.
[0042]
As shown in FIG. 5, in the sample in which the fine particle layer is omitted, when the mark length is less than 0.15 μm, the CNR value is rapidly deteriorated. This is because in the sample in which the fine particle layer is omitted, the magnetic domain cluster in the recording layer is large, the magnetization direction of the mark having a mark length of less than 0.15 μm becomes unstable, and a minute mark cannot be held. On the other hand, in a sample provided with a fine particle layer in which spherical particles are arranged, the CNR value is 40 dB or more even when the mark length is reduced to 0.1 μm. This is because even if the magnetic domain cluster in the recording layer is small and the mark length is as small as 0.1 μm, the mark can be held firmly. However, when the mark length is about 0.07 μm, the value of CNR falls below the value of 40 dB. In contrast, in the magneto-optical recording medium 1 shown in FIG. 1, the CNR value is 40 dB or more even when the mark length is shortened to about 0.07 μm. The difference between the two results from the ease of domain wall movement in the reproducing layer during reproduction. That is, in a sample having a fine particle layer in which spherical particles are arranged, the hemispherical shape of the upper half of the particles is reflected to the reproduction layer, and a magnetic domain cluster is also formed in the reproduction layer. For this reason, the domain wall movement in the reproduction layer at the time of reproduction is hindered, and the domain wall of the reproduction layer cannot move to the high temperature side according to the temperature gradient of the reproduction layer, which leads to a decrease in CNR. However, in the magneto-optical recording medium 1 shown in FIG. 1, since the projecting surface of the convex portion of the concavo-convex pattern provided on the fine particle layer 11 is a flat surface, the reproducing layer is a flat layer, and the reproducing layer has magnetic domain clusters. Not formed. For this reason, at the time of reproduction, the domain wall of the reproduction layer can move to the high temperature side according to the temperature gradient of the reproduction layer, and the CNR is also a good value.
[0043]
In the description here, the DWDD medium and the manufacturing method thereof have been described. However, the magneto-optical recording medium of the present invention can also be applied to a MAMMOS medium, and the manufacturing method of the magneto-optical recording medium of the present invention is as follows. The present invention can also be applied to a method for manufacturing a MAMMOS medium.
[0044]
Hereinafter, various aspects of the present invention will be additionally described.
[0045]
(Supplementary note 1) In a magneto-optical recording medium that receives a magnetic field and has marks of a predetermined size magnetized in a direction corresponding to the supplied magnetic field continuously formed in a predetermined direction.
A substrate,
A particle layer provided on the substrate and having a particle size smaller than the size of the mark and having a flat surface on the surface forming the external shape, and a fine particle layer arranged in the predetermined direction with the flat surface facing upward,
A recording layer provided on the fine particle layer and on which the mark is formed;
A reproducing layer provided on the recording layer and magnetized in the same direction as the magnetization direction of the mark formed on the recording layer and having a region larger than the size of the mark. Magneto-optical recording medium.
[0046]
(Additional remark 2) The said particle | grain is a thing of a particle size of 10 nm or less, The magneto-optical recording medium of Additional remark 1 characterized by the above-mentioned.
[0047]
(Appendix 3) An intermediate layer having a Curie temperature lower than the Curie temperature of both the recording layer and the reproduction layer is formed between the recording layer and the reproduction layer. The magneto-optical recording medium according to appendix 1.
[0048]
(Supplementary note 4) The magneto-optical recording medium according to supplementary note 1, wherein the particles are nonmagnetic and have a polyhedral crystal structure.
[0049]
(Supplementary note 5) The magneto-optical recording medium according to supplementary note 1, wherein the particle contains one of Pt atoms and Au atoms.
[0050]
(Additional remark 6) In the manufacturing method of the magneto-optical recording medium which receives supply of a magnetic field and the mark of the predetermined magnitude | size magnetized in the direction according to the supplied magnetic field is continuously formed in a predetermined direction,
By reducing a solution obtained by adding a polymer material to a solution in which predetermined particles are dissolved, the particle size is smaller than the size of the mark, and the surface forming the external shape has a flat surface. A coating liquid production process for producing a coating liquid in which particles whose surfaces are coated with the polymer material are dispersed;
A coating liquid produced by the coating liquid production process is applied onto a substrate, and a fine particle layer in which particles dispersed in the coating liquid are arranged in the predetermined direction with the plane facing up is applied on the substrate. A fine particle layer forming step to be provided;
A recording layer forming step of providing a recording layer on which the mark is formed on the fine particle layer provided by the fine particle layer forming step;
A reproduction layer is provided on the recording layer provided by the recording layer forming step, in which a reproduction layer is formed which is magnetized in the same direction as the magnetization direction of the mark formed on the recording layer and has a region larger than the size of the mark. A method of manufacturing a magneto-optical recording medium, comprising: a layer forming step.
[0051]
(Supplementary note 7) The method for producing a magneto-optical recording medium according to supplementary note 6, wherein the polymer material is a material mainly comprising one of polyvinylpyrrolidone and sodium polyacrylate.
[0052]
(Supplementary note 8) The method for producing a magneto-optical recording medium according to supplementary note 6, wherein the reduction in the coating liquid production step is one of alcohol reduction and hydrogen reduction.
[0053]
(Supplementary note 9) The method for producing a magneto-optical recording medium according to supplementary note 6, wherein the particle contains a metal atom and has a particle size of 10 nm or less.
[0054]
(Supplementary Note 10) After the recording layer forming step and before the reproducing layer forming step, a Curie temperature lower than the Curie temperature of both the recording layer and the reproducing layer on the recording layer. The method for producing a magneto-optical recording medium according to appendix 6, further comprising an intermediate layer forming step of providing an intermediate layer having the following characteristics.
[0055]
【The invention's effect】
As described above, according to the present invention, there is provided a magneto-optical recording medium including an underlayer on which a fine concavo-convex pattern that does not affect the reproducing layer is formed, and a method for manufacturing such a magneto-optical recording medium. Can be provided.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view of a magneto-optical recording medium according to the present embodiment taken along a groove extending direction.
FIG. 2 is a flowchart showing each process in manufacturing the magneto-optical recording medium shown in FIG. 1;
FIG. 3 is a diagram schematically showing a substrate on which a coating solution has been applied by a spin coating method.
FIG. 4 is a view schematically showing a substrate after the coating liquid is naturally dried.
5 is a graph showing the mark length dependence of CNR in the magneto-optical recording medium shown in FIG. 1. FIG.
[Explanation of symbols]
1 magneto-optical recording medium 10 substrate 11 fine particle layer 111 Pt fine particle 111a plane 12 recording layer 13 intermediate layer 14 reproducing layer 15 protective layer

Claims (5)

In a magneto-optical recording medium in which a mark having a predetermined size magnetized in a direction corresponding to a supplied magnetic field is continuously formed in a predetermined direction.
A substrate,
Particles having a particle size smaller than the size of the mark provided on the substrate and having a flat surface on the surface forming the external shape are arranged in the predetermined direction with the flat surface facing upward, and a fine uneven pattern A fine particle layer formed with,
A recording layer provided on the fine particle layer and on which the mark is formed;
A reproducing layer provided on the recording layer and magnetized in the same direction as the magnetization direction of the mark formed on the recording layer, wherein a region larger than the size of the mark is formed during reproduction. A magneto-optical recording medium.   2. The magneto-optical recording medium according to claim 1, wherein the particles have a particle size of 10 nm or less.   2. The intermediate layer having a Curie temperature lower than the Curie temperature of both the recording layer and the reproducing layer is formed between the recording layer and the reproducing layer. Magneto-optical recording medium. In a method of manufacturing a magneto-optical recording medium, wherein a mark having a predetermined size, which is magnetized in a direction corresponding to a supplied magnetic field, is continuously formed in a predetermined direction.
By reducing a solution obtained by adding a polymer material to a solution in which predetermined particles are dissolved, the particle size is smaller than the size of the mark, and the surface forming the external shape has a flat surface. A coating liquid production process for producing a coating liquid in which particles whose surfaces are coated with the polymer material are dispersed;
A coating solution manufactured by the coating solution manufacturing process is applied onto a substrate, and particles dispersed in the coating solution are finely arranged on the substrate in the predetermined direction with the plane facing up. A fine particle layer forming step of providing a fine particle layer on which an uneven pattern is formed ;
A recording layer forming step of providing a recording layer on which the mark is formed on the fine particle layer provided by the fine particle layer forming step;
On the recording layer provided by the recording layer forming step, a reproducing layer magnetized in the same direction as the magnetization direction of the mark formed on the recording layer and having a region larger than the size of the mark at the time of reproduction is formed. And a reproducing layer forming step for providing a magneto-optical recording medium.   An intermediate layer having a Curie temperature lower than the Curie temperature of both the recording layer and the reproducing layer on the recording layer after the recording layer forming step and before the reproducing layer forming step. 5. The method of manufacturing a magneto-optical recording medium according to claim 4, further comprising an intermediate layer forming step of providing the intermediate layer.

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