JP2001338447A - Method and device for manufacturing optical recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily remove foreign matter existing on an information signal layer efficiently and restrain minute projecting faults from being generated on a light transmitting layer. SOLUTION: A substrate holding mechanism 2 is moved in parallel along the surface of a disk substrate 1 while an adhesive layer formed on the columnar side face of a weakly adhesive roll 3 is brought into contact with the exposed surface of the information signal part formed on the surface of the substrate 1. The foreign matter on the exposed surface of the information signal part are removed by transferring the foreign matter to the columnar side face of the roll 3. The foreign matter adhered to the roll 3 are then transferred to a strongly adhesive roll 4 to remove the foreign matter from the roll 3. A light transmitting sheet is adhered to the foreign matter removed information signal part while interposing an adhesive ultraviolet-curing resin to form the light transmitting layer so that an optical disk can be manufactured. The recording/reproducing of an information signal is performed on the optical disk by irradiating the substrate 1 with a laser beam from the side where the information signal part and the light transmitting layer are formed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical recording medium manufacturing method and an optical recording medium manufacturing apparatus.
By irradiating a laser beam to an optical disc having a recording layer and a light transmission layer provided on a substrate from the side where the light transmission layer is provided, an optical recording medium on which information signals are recorded and / or reproduced is formed. It is suitable for application.

[0002]

2. Description of the Related Art Conventionally, the production of widely known optical disks has been carried out as follows. That is, first, a replica substrate made of a light-transmitting plastic having irregularities formed on one surface is manufactured. Next, a reflective film and a recording film are laminated on the surface of the optical disc on which the irregularities are formed. As a result, an information signal portion composed of these laminated films is formed. Next, a protective layer is formed on the information signal portion. Recording / reproducing of information with respect to this optical disk is performed by irradiating a laser beam from a surface opposite to a surface on which unevenness is formed.

In such an optical disk, a replica substrate plays a role of a light transmitting layer. Therefore, in order to realize a large-capacity optical disk having a recording capacity of 8 GB or more, a thin disk substrate is required.

However, since this disk substrate is usually formed by an injection molding method, there is practically a limit to the reduction in thickness. For example, when producing a disc substrate having a diameter of 120 mm, the transferability of irregularities is at a normal level,
That is, in order to secure the level of the conventional optical disk, the thickness of the disk substrate is limited to about 300 μm. Further, in order to accurately transfer fine irregularities to an optical disk substrate in order to meet a demand for a large storage capacity, the thickness of the optical disk substrate is 500 μm.
m is the limit.

[0005] Therefore, it is very difficult to produce an optical disk substrate having a thickness of about 100 µm and fine irregularities accurately transferred thereon by an injection molding method.

[0006] The above is caused by a problem inherent in the injection molding method. That is, it is caused by unevenness in the flow state of the molten resin used as the injection material in the mold, uneven cooling rate in the mold (uneven temperature and viscosity of the molten resin), and the like.

Under such circumstances, a light transmitting layer of 177 μm or less is formed on the substrate on which the information signal is formed, and a laser beam is irradiated from the side on which the light transmitting layer is formed to record the information signal. There has been proposed an optical disc for performing / playback (for example, Japanese Patent Laid-Open No. 10-302310).

In this optical disk, the optical disk substrate can be formed to a normal thickness of about 0.6 mm or about 1.2 mm. Therefore, even when the disk substrate is manufactured by the injection molding method, it is possible to accurately transfer the unevenness. On the other hand, laser light for recording / reproduction is emitted from the side where the thin light transmitting layer is provided, so that it is possible to sufficiently cope with an increase in recording capacity.

By the way, in the case of an optical disk for recording / reproducing information signals by irradiating a laser beam from the side where the light transmitting layer is provided, a change in the film thickness of the light transmitting layer greatly affects the characteristics of the optical disk. give. Therefore, it is a big problem how to form the light transmitting layer.

Therefore, various techniques have been proposed for forming the light transmitting layer. Specifically, as a method for forming the light transmitting layer, a method of applying an ultraviolet curable resin on a disk substrate by a spin coating method (Japanese Patent Application Laid-Open No. 10-289489), a method of bonding a light transmissive sheet with an ultraviolet curable resin. There has been proposed a forming method (Japanese Patent Laid-Open No. 10-283638), a method of forming a light-transmitting sheet by bonding with an adhesive (Japanese Patent Laid-Open No. 11-126377), and the like.

Therefore, the present inventor has manufactured an optical disk in which recording / reproduction is performed by irradiating a laser beam from the side provided with the light transmitting layer according to the method described above. That is, an information signal portion having a recording layer was formed on a disk substrate, and then the above-mentioned light transmitting layer having a thickness of 177 μm or less was formed on the information signal portion to manufacture an optical disk.

[0012]

However, the inventor of the present invention has conducted various inspections on the optical disk manufactured as described above, and has found that minute defects occur in the light transmitting layer. .

The present inventor has conducted experiments and intensive studies on the cause of the generation of minute defects in the light transmitting layer, and as a result, has found the following problems. That is, in the above-described optical disc manufacturing process, after forming an information signal layer such as a recording layer by a physical vapor deposition method such as a vacuum evaporation method or a sputtering method, a light transmitting layer is formed so as to cover the information signal layer. Has formed. Then, during the process of forming the recording layer, foreign matter such as sputter flakes is generated and adheres to the recording layer, and as a result, a projection-like minute defect occurs in the light transmitting layer. I came to know that it would.

Accordingly, it is an object of the present invention to be able to easily remove a foreign substance present on an information signal layer in an optical recording medium, whereby a light-transmitting layer formed on the information signal layer has a projection-like microscopic structure. The occurrence of various defects,
An object of the present invention is to provide a method for manufacturing an optical recording medium and an apparatus for manufacturing an optical recording medium, which can prevent the occurrence of the optical recording medium and can manufacture an optical recording medium having high reliability.

[0015]

To achieve the above object, a first aspect of the present invention is a method for forming at least one information signal layer on a substrate by physical vapor deposition, comprising the steps of: Forming a light transmitting layer on the information signal layer on the side where the information signal layer is present, and recording and / or reproducing the information signal from the side where the light transmitting layer is present. In the method for manufacturing an optical recording medium configured to irradiate the layer with a laser beam, after the step of forming the information signal layer and before the step of forming the light transmitting layer, the first column-shaped first layer is formed. The first pressure-sensitive adhesive layer provided on the cylindrical side surface of the pressure-sensitive adhesive roll is brought into contact with the exposed surface of the information signal layer, and the first pressure-sensitive adhesive roll is moved relatively to the exposed surface of the information signal layer. Characterized by having a step of causing Than it is.

In the first invention, in order to maintain the adhesive strength of the first adhesive roll for a sufficiently long time, typically, the first adhesive roll has a second adhesive layer provided with an adhesive second adhesive layer. 2 in the first adhesive roll,
And the foreign matter adhering to the first adhesive layer is transferred to the second adhesive layer. In the first invention, in order to efficiently transfer foreign matter from the surface of the first pressure-sensitive adhesive layer to the second pressure-sensitive adhesive layer in the first pressure-sensitive adhesive roll, the pressure-sensitive adhesive force of the second pressure-sensitive adhesive layer is typically used. Is larger than the adhesive strength of the first adhesive layer, and preferably, the adhesive strength of the second adhesive layer is 3.5 times or more and 30 times or less of the adhesive strength of the first adhesive layer. The adhesive strength of the second adhesive layer is 6.86 × 10 ³ N / m ² or more and 1.96 × 1
0 ⁴ N / m ² or less. In the first invention, as a preferred example, the pressure-sensitive adhesive body is formed of a second pressure-sensitive adhesive roll having a columnar shape and a second pressure-sensitive adhesive layer provided on a side surface of the column, and a roll of the second pressure-sensitive adhesive roll. The diameter is larger than the diameter of the first adhesive roll. In a further preferred embodiment of the first invention, the pressure-sensitive adhesive body is a belt-shaped pressure-sensitive adhesive belt having at least one surface provided with a second pressure-sensitive adhesive layer.

In the first invention, typically, the physical vapor deposition method is a sputtering method or a vacuum evaporation method. As the sputtering method, specifically, a collimated sputtering method, a two-electrode sputtering method, Polar sputtering, quadrupole sputtering, high-speed low-temperature sputtering, counter electrode sputtering (magnetron sputtering), ECR (Electron Cyclotron Resonanc)
e) A sputtering method, a high frequency (RF) sputtering method, a reactive sputtering (reactive sputtering method), a bias sputtering method, an asymmetric AC sputtering method, a getter sputtering method, or the like is employed.

According to a second aspect of the present invention, at least an information signal layer is provided on a substrate, and the substrate is irradiated with light from the side on which the information signal layer is provided to record and / or record information signals.
Alternatively, in an apparatus for manufacturing an optical recording medium used for manufacturing an optical recording medium on which reproduction is performed, the apparatus includes a first adhesive roll having a cylindrical shape, and a substrate holding unit configured to hold a substrate. A first pressure-sensitive adhesive layer is provided on the side surface of a cylinder of the pressure-sensitive adhesive roll, and the first pressure-sensitive adhesive roll is configured to be able to contact the first pressure-sensitive adhesive layer and the exposed surface of the information signal layer, and the substrate holding means It is characterized by being configured to be relatively movable with respect to.

In the second invention, in order to maintain the adhesive force of the first adhesive roll for a sufficiently long time,
The optical recording medium manufacturing apparatus typically further includes an adhesive body provided with a second adhesive layer, and a first adhesive layer in the first adhesive roll and a second adhesive layer in the adhesive body. Are configured to be able to contact each other. Also, this second
In the invention of the first aspect, in order to constitute the foreign matter attached to the surface of the first adhesive layer in the first adhesive roll so as to be transferable from the first adhesive layer to the second adhesive layer, typically, the second adhesive layer Is configured so that the adhesive strength of the first adhesive layer is greater than the adhesive strength of the first adhesive layer. Preferably, the adhesive strength of the second adhesive layer is 3.5 times the adhesive strength of the first adhesive layer. 3 times or more
It is configured to be 0 times or less, and specifically, the adhesive force of the second adhesive layer is 6.86 × 10 ³ N / m ² or more and 1.96.
It is configured to be less than × 10 ⁴ N / m ² . Further, in the second invention, as a preferred example, the pressure-sensitive adhesive body is formed of a second pressure-sensitive adhesive roll having a columnar shape, and a second pressure-sensitive adhesive layer is provided on a side surface of the second roller in the shape of a column,
The second adhesive roll is configured such that its roll diameter is larger than the roll diameter of the first adhesive roll. In the first invention, as a further preferred example, typically, the pressure-sensitive adhesive body is formed of a belt-shaped pressure-sensitive adhesive belt provided with a second pressure-sensitive adhesive layer on at least one surface.

In the present invention, in order to efficiently adhere foreign substances on the surface of the information signal layer without causing separation of the information signal layer, the adhesive force of the first adhesive layer is preferably:
It is 6.86 × 10 ² N / m ² or more and 1.96 × 10 ³ N / m ² or less. Moreover, in this invention, the adhesive force uses the roller measured according to Japanese Industrial Standard (JIS-K-6854).

In the present invention, in order to realize recording / reproducing on an optical recording medium to be manufactured, typically, the light transmitting layer includes at least information signal recording and / or recording.
Alternatively, it is made of a material capable of transmitting a laser beam applied to the information signal layer during reproduction.

According to the method for manufacturing an optical recording medium and the apparatus for manufacturing an optical recording medium according to the present invention configured as described above, after the information signal layer is formed, the side surface of the cylindrical first adhesive roll is formed on the side surface of the cylinder. The first adhesive layer having adhesiveness provided is brought into contact with the exposed surface of the information signal layer, and the first adhesive roll is moved relatively to the exposed surface of the information signal layer. Thus, the foreign substances existing on the information signal layer surface can be transferred to the first adhesive layer of the first adhesive roll, so that the foreign substances existing on the information signal layer can be efficiently removed.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. In all the drawings of the following embodiments, the same or corresponding portions are denoted by the same reference numerals.

First, a foreign matter removing apparatus constituting a part of the optical disk manufacturing apparatus according to the first embodiment of the present invention will be described. FIG. 1 shows a foreign matter removing apparatus according to the first embodiment. The optical disc according to the first embodiment irradiates a laser beam from a light transmitting layer side provided on a support substrate having an information signal portion to record / record an information signal.
Reproduction is performed.

As shown in FIG. 1, the foreign matter removing apparatus according to the first embodiment includes at least a substrate holding mechanism 2 for holding a disk substrate 1, a weak adhesive roll 3 having relatively low adhesive strength, and It has a strong adhesive roll 4 having a higher adhesive strength than the weak adhesive roll 3.

The substrate holding mechanism 2 is provided with a disk stage 5 on an upper portion thereof, and is configured to freely circulate. At the upper end of the disk stage 5, a vacuum suction unit (not shown) for holding a substrate, which is formed of, for example, a vacuum chuck or the like, is provided. Further, the substrate holding mechanism 2
The disk stage 5 is driven by a driving mechanism (not shown).
It is configured to be freely movable / movable in a direction substantially parallel to the upper surface (the direction indicated by an arrow in FIG. 1).

The weak adhesive roll 3 has a cylindrical shape, is configured to be rotatable about a rotation axis 3a parallel to the surface of the disk substrate 1, and has at least an adhesive layer ( (Not shown). The weak adhesive roll 3 is for removing foreign matter present on an exposed surface of a recording layer formed on the disk substrate 1 described later. Then, in order to efficiently remove foreign matter attached to the recording layer surface on the disk substrate 1,
The width of the weak adhesive roll 3 (length along the longitudinal direction of the weak adhesive roll 3) is configured to be slightly larger than the diameter of the disk substrate 1.

The diameter (roll diameter) of the weak adhesive roll 3 in a cross section perpendicular to the rotation axis 3a is determined in consideration of the allowable size of the foreign matter removing device and the adhesive force. That is, as the roll diameter of the weak adhesive roll 3 is larger, the outer peripheral surface area is larger, which is advantageous from the viewpoint of maintaining the adhesive strength. On the other hand, if the roll diameter of the weak adhesive roll 3 is too large, the size of the foreign matter removing device is increased, which is not preferable from the viewpoint of space saving. Therefore, the roll diameter of the weak adhesive roll 3 is set to an appropriate size in consideration of these viewpoints. The roll diameter of the weak adhesive roll 3 is
Specifically, the first is selected from a range of 30 to 200 mm.
In the embodiment, the distance is selected, for example, to 50 mm.

Further, the adhesive force of the weak adhesive roll 3 is such that foreign substances adhering to the exposed surface of the recording layer on the disk substrate 1 can be sufficiently removed, and the production of the disk substrate 1 can be performed without any trouble. It is decided in consideration of. That is, if the adhesive force of the adhesive layer applied to the cylindrical side surface of the weak adhesive roll 3 is too small, foreign substances attached to the exposed surface of the recording layer on the disk substrate 1 cannot be sufficiently removed. On the other hand, if the adhesive force is too large, the signal information portion having the recording layer and the reflective layer on the disk substrate 1 may peel off, or the disk substrate 1 itself may be detached from the vacuum suction portion of the disk stage 5. There is. Therefore, the adhesive force of the weak adhesive roll 3 is set to an appropriate size in consideration of these points, and specifically, 6.86 × 10 ^{2 to} 1.96.
× 10 ³ N / m ² (7 to ²⁰ gf / cm ² )
In the first embodiment, for example, 9.8 × 10 ²
N / m ² (10 gf / cm ² ). The details of the adhesive strength of the weak adhesive roll 3 will be described later.

The strong adhesive roll 4 has a cylindrical shape, and is configured to be rotatable about a rotation axis 4a parallel to the surface of the disk substrate 1 and parallel to the rotation axis 3a of the weak adhesive roll 3. At the same time, an adhesive layer (not shown) is provided on at least the side surface of the column. The cylindrical side surface of the strong adhesive roll 4 and the cylindrical side surface of the weak adhesive roll 3 are configured to be able to contact each other. Then, the strong adhesive roll 4 causes the weak adhesive roll 3 to move from the surface of the disk substrate 1.
The foreign matter transferred to the side surface of the column can be removed from the adhesive layer of the weak adhesive roll 3. The width of the strong adhesive roll 4 (the length along the longitudinal direction of the strong adhesive roll 4) is set so that the foreign matter attached to the adhesive layer on the side surface of the column in the weak adhesive roll 3 is efficiently removed. It is configured to have a width of 3 or more.

The diameter (roll diameter) of the strong adhesive roll 4 in a cross section perpendicular to the rotation axis 4a is determined in consideration of the allowable size of the foreign matter removing device and the adhesive force. That is, the larger the roll diameter of the strong adhesive roll 4 is, the larger its outer peripheral surface area is, which is advantageous from the viewpoint of maintaining the adhesive strength. On the other hand, if the roll diameter of the strongly adhesive roll 4 is too large, the size of the foreign matter removing device is increased, which is not preferable from the viewpoint of space saving. Therefore, the roll diameter of the strong adhesive roll 4 is set to an appropriate size in consideration of these viewpoints. That is, the roll diameter of the strong adhesive roll 4 is specifically selected from the range of 50 to 300 mm, and in the first embodiment, for example, 120 mm
Is chosen.

The adhesive force of the strong adhesive roll 4 is designed to remove foreign substances adsorbed on the side surface of the column of the weak adhesive roll 3 and to prevent trouble from occurring to the weak adhesive roll 3. Set to size. That is, if the adhesive force of the adhesive layer on the cylindrical side surface of the strong adhesive roll 4 is too small, the foreign matter adsorbed on the weak adhesive roll 3 cannot be sufficiently transferred to the strong adhesive roll 4. On the other hand, when the adhesive force of the adhesive layer on the cylindrical side surface of the strong adhesive roll 4 is too large, the adhesive layer adhered to the cylindrical side surface of the weak adhesive roll 3 may be peeled off. In consideration of these viewpoints, the adhesive strength of the strong adhesive roll 4 is set to be at least larger than the adhesive strength of the weak adhesive roll 3, and specifically, 6.86 × 10 ^{3 to} 1.96 × 10 ⁴ N / m ² (70
２００200 gf / cm ² ), and in the first embodiment, for example, 1.32 × 10 ⁴ N / m ² (135)
gf / cm ² ). In addition, this strongly adhesive roll 4
The details regarding the adhesive strength of will be described later.

Next, a method of manufacturing an optical disk according to the first embodiment, which has a foreign matter removing step performed by using the foreign matter removing apparatus configured as described above, will be described. FIG. 2 shows a disk substrate 1 from which foreign matter is removed according to the first embodiment.

As shown in FIG. 2, in the disk substrate 1 from which foreign matter is removed according to the first embodiment, a center hole 11 is formed at the center of the replica substrate 1a, and the information hole is formed on one main surface thereof. A signal section 12 is provided.

The replica substrate 1a is manufactured by an injection molding method using a predetermined stamper. In addition, on the uneven portion formed on one main surface of the replica substrate 1a,
A recording film, a reflection film, and the like are formed, and the information signal portion 12 is formed by this. Also, the replica substrate 1a
Has a thickness of, for example, 0.6 to 1.2 mm. The information signal section 12 is formed of a reflective film, a film made of a magneto-optical material, a film made of a phase change material, an organic dye film, or the like. The material of the reflection film is, for example, aluminum (Al).
Are used. More specifically, when the optical disc as the final product is a read-only (ROM) optical disc, the information signal section 12 is a single-layer film or a laminated film having at least a reflective layer made of, for example, Al. Consists of On the other hand, when the optical disk from which foreign matter is to be removed is a rewritable optical disk, the information signal section 12 is composed of a single-layer film or a laminated film having at least a film made of a magneto-optical material or a film made of a phase-change material. In the case of a write-once optical disc, it is composed of a single layer film or a laminated film having at least a film made of an organic dye material.

Here, the disk substrate 1 according to the first embodiment is concretely used as a replica substrate 1a, for example, in a disk-shaped polycarbonate (P) having a thickness of 1.1 mm.
C) A substrate having a thickness of 100
A first dielectric layer made of a mixture of zinc sulfide (ZnS) and silicon oxide (SiO ₂ ) having a thickness of 18 nm on a reflective layer made of an Al alloy having a thickness of 24 nm, and GeS having a thickness of 24 nm.
a phase change recording layer comprising a bTe alloy layer and a film thickness of 10
A second dielectric layer made of a mixture of ZnS and SiO ₂ having a thickness of 0 nm is sequentially laminated.

After forming the information signal section 12, the disk substrate 1 is transported to the substrate holding mechanism 2 and mounted on the disk stage 5. Then, the disk substrate 1 is suction-held by using a vacuum suction portion (not shown) formed of a vacuum chuck. Next, as shown in FIG. 1, while holding the disk substrate 1 by suction, the substrate holding mechanism 2 is moved in a direction parallel to the surface of the disk substrate 1. With the movement of the substrate holding mechanism 2, the surface of the disk substrate 1 is pressed against the cylindrical side surface of the weak adhesive roll 3, and
Is rotated, and the strongly adhesive roll 4 is rotated in conjunction with this rotation. Thereby, the information signal unit 1 of the disk substrate 1
Foreign matter, such as sputter flakes, present on the surface of the disk substrate 1 is adsorbed by the adhesive layer (not shown) on the side of the cylinder of the weak adhesive roll 3 and removed from the surface of the information signal section 12 on the disk substrate 1. Then, the foreign matter removed from the disk substrate 1 is
In the state of being attached to the weak adhesive roll 3, the weak adhesive roll 3
Is moved to the contact portion with the strong adhesive roll 4 with the rotation of. Then, in this contact portion, the foreign matter is adsorbed by the strong adhesive roll 4 and transferred and removed from the cylindrical side surface of the weak adhesive roll 3.

Next, a light transmitting layer is formed on the disk substrate 1 from which the foreign matter has been removed. That is, as shown in FIG. 3, first, the disk substrate 1 from which foreign matter has been removed is placed on the spindle 21 so as to penetrate the center hole 11 of the disk substrate 1. Next, an ultraviolet curable resin (transparent adhesive) is formed on the surface of the disk substrate 1 on which the irregularities are formed.
22.

Next, a light transmissive sheet 23 is placed above the disk substrate 1 to which the ultraviolet curable resin 22 is supplied so that the center thereof is supported by the spindle 21. The thickness of the light transmitting sheet 23 is, for example, 95 μm. Next, the surface of the disk substrate 1 on which the irregularities are formed and one main surface of the light-transmitting sheet 23 are bonded via the ultraviolet curing resin 22. Next, the disk substrate 1 and the light-transmitting sheet 23 are integrally rotated in the in-plane direction (M direction). Thereby, the ultraviolet curing resin 22 spreads between the disk substrate 1 and the light transmitting sheet 23.

Thereafter, ultraviolet rays are applied to the disk substrate 1 from the side of the light-transmitting sheet 23 toward the ultraviolet curing resin 22, so that the ultraviolet curing resin 22 is cured. Thereby, the disk substrate 1 and the light transmitting sheet 23
Are bonded via the ultraviolet curable resin layer 22a. Here, the thickness of the ultraviolet curable resin layer 22a is, for example, 5 μm.
It is.

As described above, as shown in FIG. 4, the light transmitting layer 24 composed of the ultraviolet-curable resin layer 22a and the light transmitting sheet 23 is formed on the uneven surface of the disk substrate 1. An optical disc according to the first embodiment is manufactured.

Next, the reason for setting the adhesive strength of the adhesive layer on the cylindrical side surface of the above-mentioned weak adhesive roll 3 and strong adhesive roll 4 will be described below.

The inventor conducted the following experiment on the adhesive strength of the weak adhesive roll 3. That is, first, powder particles (SUS powder) made of stainless steel (SUS) classified to a size of 25 μm or less by a precision sieve are
Sprinkle on a disk substrate 1 made of polycarbonate. At this time, the surface density of the SUS powder spread on the disk substrate is set to 500 to 600 per 1 cm ² .

Thereafter, with respect to the surface of the disk substrate 1,
The weak adhesive roll 3 having variously changed adhesive strengths is rolled as shown in FIG. Here, the load applied to the disk substrate 1 by the weak adhesive roll 3 is 9.80 × 10 ⁻¹ N (10
0gf), and the adhesive force of the weak adhesive roll 3 is 4.90 ×
10 ^{2 to} 4.90 × 10 ³ N / m ² (5 to 50 gf / c
m ² ), specifically, 4.90 × 10 ² N / m ² (5
gf / cm ² ), 6.86 × 10 ² N / m ² (7 gf / c
m ² ), 9.80 × 10 ² N / m ² (10 gf / cm ² ),
2.94 × 10 ³ N / m ² (30 gf / cm ² ), 4.9
0 × 10 ³ N / m ² (50 gf / cm ² ).

Then, adhere to the cylindrical side surface of the weak adhesive roll 3
Without removing from the surface of the information signal section 12 on the disk substrate 1
The unit area of the SUS powder (1
mm ^Two) Per unit (number density)
It was measured by a loop. The result is shown in FIG.

FIG. 5 shows that the number density of the SUS powder particles remaining on the surface of the disk substrate 1 indicates that the adhesive force of the weak adhesive roll 3 is 4.90 × 10 ² N / m ² (5 gf / c).
m ² ), it is 3.5 pieces / mm ² , and when the adhesive strength is 6.86 × 10 ² N / m ² (7 gf / cm ² ) or more, it is 0.25 pieces / mm ² or less. It turns out that it becomes.
That is, the adhesive force of the weak adhesive roll 3 is 6.86 × 10 ²
It can be seen that the number of SUS powder particles remaining on the disk substrate can be significantly reduced by setting the N / m ² or more. Therefore, it is understood that the adhesive strength of the weak adhesive roll 3 is preferably set to 6.86 × 10 ² N / m ² or more.

The present inventor conducted the following experiment on the adhesive strength of the strongly adhesive roll 4. That is, first,
The SUS powder classified to a size of 25 μm or less by a precision sieve is sprinkled on the cylindrical side surface of the weak adhesive roll 3. Here, as the weak adhesive roll 3 on which the SUS powder is spread, the adhesive strength is 9.80 × 10 ² N / m ² , 19.6 ×
Those of 10 ² N / m ² and 29.4 × 10 ² N / m ² are used. Further, the surface density of the SUS powder to be sprinkled on the cylindrical side surface of the weak adhesive roll 3, 1 cm ² per 500
The number is assumed to be 600.

Next, the strong adhesive rolls 4 having variously changed adhesive strengths are rolled on the cylindrical side surfaces of the weak adhesive rolls 3 with their longitudinal directions parallel to each other. Here, the load applied to the weak adhesive roll 3 by the strong adhesive roll 4 is set to 9.8 × 10 ⁻¹ N (100 gf),
The adhesive strength of the strong adhesive roll 3 is 3.92 × 10 ^{3 to} 2.9
4 × 10 ⁴ N / m ² (40 to 300 gf / cm ² )
Specifically, 3.92 × 10 ³ N / m ² (40 gf / cm
² ), 6.86 × 10 ³ N / m ² (70 gf / cm ² ),
1.67 × 10 ⁴ N / m ² (170 gf / cm ² );
96 × 10 ⁴ N / m ² (200 gf / cm ² ) and 2.94 × 10 ⁴ N / m ² (300 gf / cm ² ).

Then, the unit area (1 m) of the SUS powder particles remaining on the surface of the weak adhesive roll 3 which were not transferred and adhered to the strong adhesive roll 4 and were not removed from the side surfaces of the cylinder of the weak adhesive roll 3.
The number per m ² ) was measured with a microscope. FIG. 6 shows the result.

FIG. 6 shows that the adhesive strength of the weak adhesive roll 3 is 9.
In the case of 8 × 10 ² N / m ² , when the adhesive force of the strong adhesive roll 4 is 3.92 × 10 ³ N / m ² , the weak adhesive roll 3
The number density of SUS powder remaining on the side of the cylinder is 3.8 /
mm ² , whereas the adhesive force of the strong adhesive roll 4 is 6.
SUS remaining at 86 × 10 ³ N / m ² or more
It can be seen that the number density of the powder is 0.3 / mm ² or less. Further, the adhesive force of the weak adhesive roll 3 is 1.96 × 10 ³
In the case of N / m ² , the adhesive force of the strongly adhesive roll is 3.92 × 1
At 0 ³ N / m ² , the number density of the SUS powder remaining on the cylindrical side surface of the weak adhesive roll 3 is 3.9 / mm ² , whereas the adhesive force of the strong adhesive roll 4 is 6. 86 × 10 ³
When N / m ² or more, the number density of the remaining SUS powder becomes 0.5 / mm ² or less. Also,
When the adhesive strength of the weak adhesive roll 3 is 2.94 × 10 ³ N / m ² , even if the adhesive strength of the strong adhesive roll 4 is increased, the cylinder of the weak adhesive roll 3 is different from the above case. No sharp decrease in the number density of the SUS powder remaining on the side surface is observed. That is, the adhesive strength of the weak adhesive roll 3 is 1.96 × 10 ³ N /
and m ^2, 6.86 adhesion strength adhesive roll 4 × 1
It is understood that the number of SUS powder remaining on the side surface of the column of the weak adhesive roll 3 can be significantly reduced by setting it to 0 ³ N / m ² or more. Therefore, the adhesive strength of the strong adhesive roll 4 is determined by reducing the adhesive strength of the weak adhesive roll 3 by 1.
In the case of 96 × 10 ³ N / m ² or less, 6.86
It can be seen that it is preferable to set it to × 10 ³ N / m ² or more. Further, the present inventor performed an experiment similar to that described above by setting the adhesive force of the strongly adhesive roll 4 to 2.94 × 10 ⁴ N / m ² (300 gf / cm ² ) or more. Accordingly, it was confirmed that the pressure-sensitive adhesive layer on the cylindrical side surface of the weak pressure-sensitive adhesive roll 3 was peeled off.

From the above, the adhesive force of the weak adhesive roll 3 is 6.86 × 10 ² N / m ² or more and 1.96 × 10 ³ N / m ² or more.
m ² or less, and the adhesive strength of the strong adhesive roll 4 is 6.
It can be seen that it is preferable that the content be 86 × 10 ³ N / m ² or more and 1.96 × 10 ⁴ N / m ² or less.

Further, based on the findings from the above experiments, as a relative adhesive force, typically, the adhesive force of the strong adhesive roll 4 is set to be larger than the adhesive force of the adhesive layer of the weak adhesive roll 3, Preferably, the adhesive strength of the adhesive layer of the strong adhesive roll 4 is set to be 3.5 to 30 times the adhesive strength of the adhesive layer of the weak adhesive roll 3.

Next, the present inventor has made an optical disk manufactured by the manufacturing method including the foreign matter removing step according to the first embodiment (Example) and an optical disk manufactured by the conventional manufacturing method (Comparative Example). With respect to (1) and (2), a defect generated in the light transmission layer 24 was measured. That is, 160 optical disks are manufactured by the manufacturing method according to the first embodiment, and 160 optical disks are manufactured by the conventional manufacturing method. Extracted an optical disk having a defect of 5 μm or more. The number of the extracted optical disks is shown in Table 1 below.

[0054]

[Table 1]

As shown in Table 1, out of the 160 optical disks manufactured by the conventional manufacturing method, the number of optical disks having defects was 28 (comparative example). Of the 160 optical disks manufactured by the manufacturing method having the foreign matter removing step according to the embodiment,
The number of optical disks having defects was 5 (Example). Therefore, by rolling the weak adhesive roll 3 while contacting the surface of the information signal section 12, the information signal section 1 is rotated.
It can be seen that foreign matter existing on the exposed surface of No. 2 can be removed, and defects can be greatly reduced in an optical disc as a final product.

As described above, according to the first embodiment, after the information signal section 12 is formed on the disk substrate 1, the foreign matter removing device having the weak adhesive roll 3 and the strong adhesive roll 4 is used. On the exposed surface of the information signal unit 12,
By performing the foreign matter removing step of removing foreign matter such as sputter flakes, when the light transmitting layer 24 made of the light transmitting sheet 23 is formed on the information signal portion 12 via the ultraviolet curing resin layer 22a, Defects occurring in the transmission layer 24, particularly protrusion-like defects, can be significantly reduced, and a good optical disc can be manufactured. Therefore, the production yield in the optical disk production process can be improved, and the reliability of the optical disk can be improved. In addition, according to the foreign matter removing device according to the first embodiment, the adhesive force of the adhesive layer applied to the cylindrical side surface of the strong adhesive roll 4 is made larger than that of the weak adhesive roll 3 and adheres to the weak adhesive roll 3. By allowing the transferred foreign matter to be transferred to and removed from the strong adhesive roll 4, there is another advantage that the adhesive force of the weak adhesive roll 3 can be maintained for a long time.

Next, an apparatus for removing foreign matter from an optical disk substrate according to a second embodiment of the present invention will be described. FIG.
Next, a foreign matter removing device according to the second embodiment is shown.

As shown in FIG. 7, in the foreign matter removing apparatus according to the second embodiment, unlike the first embodiment, foreign matter adhered to the adhesive layer of the weak adhesive roll 3 is removed.
A strip-shaped or endless belt-shaped adhesive belt 31 is used as a strong adhesive body to be removed from the weak adhesive roll 3. One of the adhesive belts 31 is wound around an unwinding device 32, and the other is wound around a winding device 33. Unwinding device 32 and winding device 33
Have, for example, columnar shapes each having a central axis substantially parallel to the longitudinal direction of the weak adhesive roll 3, and the central axes 3
It is configured to be able to rotate around 2a and 33a. Further, guide rolls 34 and 35 are provided on both sides of the weak adhesive roll 3 at a distance so that the adhesive belt 31 can contact the weak adhesive roll 3. These guide rolls 34 and 35 are used to bring the adhesive belt 31 into contact with the weak adhesive roll 3 while maintaining a predetermined pressure.
1 so that a predetermined stress is generated therein. The adhesive belt 31 has the same adhesive layer as the adhesive layer provided on the cylindrical side surface of the strong adhesive roll 4 in the first embodiment, and has the same adhesive force as the adhesive layer. It is configured.

The other points are the same as those of the foreign matter removing apparatus according to the first embodiment, and the description is omitted.

Next, a foreign substance removing step using the foreign substance removing apparatus configured as described above will be described. In the foreign matter removing step according to the second embodiment, first, the disk substrate 1 on which the information signal section 12 is formed is held by the substrate holding mechanism 2 as in the first embodiment. Thereafter, the substrate holding mechanism 2 is moved in a direction substantially parallel to the surface of the disk substrate 1 (to the right in FIG. 7), and the weak adhesive roll 3 is brought into contact with the surface of the disk substrate 1. Thereby, the weak adhesive roll 3 rotates such that the cylindrical side surface having the adhesive layer rolls on the surface of the disk substrate 1.

As described above, foreign substances such as sputter flakes adhering to the surface of the information signal portion 12 of the disk substrate 1
The adhesive is transferred to and adhered to an adhesive layer (not shown) on the side of the cylinder of the weak adhesive roll 3 and is removed from the surface of the disk substrate 1. Then, the foreign matter removed from the disk substrate 1 moves to the contact portion with the adhesive belt 31 with the rotation of the weak adhesive roll 3, and is attracted to the adhesive belt 31 at this portion, and from the cylindrical side surface of the weak adhesive roll 3. It is transferred and removed.

The other method of manufacturing an optical disk including a foreign matter removing step is the same as in the first embodiment, and a description thereof will be omitted.

As described above, according to the second embodiment, foreign matter on the surface of the disk substrate 1 is transferred to the weak adhesive roll 3 and removed, and the transferred foreign matter is removed from the weak adhesive roll 3. By transferring and removing the adhesive belt 31, the same effect as in the first embodiment can be obtained, and in the first embodiment, the strong adhesive roll 4 is used to remove foreign matter from the weak adhesive roll 3. When rotated many times while removing, the foreign matter transferred from the weak adhesive roll remains as it is on the adhesive layer on the side surface of the cylinder, circulates, and there is a concern that the adhesive strength of the adhesive layer on the strong adhesive roll 4 is reduced. However, in the second embodiment, by using the adhesive belt 31 instead of the strong adhesive roll 4,
Since the pressure-sensitive adhesive layer itself of the pressure-sensitive adhesive belt 31 can be kept in a clean state and can be brought into contact with the weak pressure-sensitive adhesive roll 3, it does not cause a decrease in the pressure-sensitive adhesive force due to transfer of foreign matter from the weak pressure-sensitive adhesive roll 3. It is possible to more reliably remove foreign matter from the surface of the disk substrate 1. Therefore, a more reliable and higher quality optical disc can be manufactured.

Although the embodiments of the present invention have been specifically described above, the present invention is not limited to the above embodiments, and various modifications based on the technical idea of the present invention are possible.

For example, the numerical values, materials, and configurations of the optical discs described in the above embodiments are merely examples.
If necessary, different numerical values, materials, and configurations of the optical disk may be used.

[0066]

As described above, according to the present invention, after the step of forming the information signal layer on the substrate and before the step of forming the light transmitting layer, the first adhesive roll having a cylindrical shape is used. The first pressure-sensitive adhesive layer provided on the side surface of the cylinder is brought into contact with the exposed surface of the information signal layer, and the first adhesive roll is moved relatively to the exposed surface of the information signal layer. By doing so, foreign substances present on the information signal layer surface can be transferred to the first adhesive layer of the first adhesive roll, so that foreign substances present on the information signal layer can be efficiently removed. In addition, it is possible to suppress and prevent the occurrence of protrusion-like defects in a light transmission layer formed later, and to manufacture an optical recording medium having high reliability.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing an apparatus for removing foreign matter from a disk substrate according to a first embodiment of the present invention.

FIG. 2 is a sectional view showing a disk substrate from which foreign matter is removed according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view for explaining a method of forming a light transmitting layer according to the first embodiment of the present invention.

FIG. 4 is a sectional view showing the optical disc according to the first embodiment of the present invention.

FIG. 5 is a graph showing the dependence of the number density of SUS powder remaining on a disk substrate on the adhesive force of a weak adhesive roll.

FIG. 6 is a graph showing the dependency of the number density of SUS powder remaining on the surface of the weak adhesive roll on the adhesive force of the strong adhesive roll.

FIG. 7 is a schematic diagram illustrating an apparatus for removing foreign matter from an optical disc according to a second embodiment of the present invention;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Disk substrate, 1a ... Replica substrate, 2
..Substrate holding mechanism, 3 ... weak adhesive roll, 3a ...
Rotary axis, 4 ... strong adhesive roll, 4a ... rotary axis, 1
2 ... information signal section, 21 ... spindle, 22 ...
UV curable resin, 22a UV curable resin layer, 2
3 ... light transmissive sheet, 24 ... light transmissive layer, 31
..Adhesive belts

Claims (20)

[Claims] A step of forming at least one information signal layer on a substrate by physical vapor deposition, and a step of forming an optical signal on the information signal layer on the side of the substrate where the information signal layer exists. Forming a transmissive layer, and recording and / or reproducing the information signal by irradiating the information signal layer with laser light from the side where the light transmissive layer exists. In the method for manufacturing a medium, after the step of forming the information signal layer and before the step of forming the light transmitting layer, the second adhesive layer provided on the side surface of the cylindrical first adhesive roll and having an adhesive property. An optical recording medium comprising a step of bringing the first adhesive layer into contact with the exposed surface of the information signal layer and moving the first adhesive roll relative to the exposed surface of the information signal layer. Manufacturing method. 2. The adhesive force of the first adhesive layer is:
^{2. The} method for manufacturing an optical recording medium according to claim 1, wherein the optical recording medium has a density of 6.86 × 10 ² N / m ² or more and 1.96 × 10 ³ N / m ² or less. 3. The first pressure-sensitive adhesive body provided with a second pressure-sensitive adhesive layer, the second pressure-sensitive adhesive layer is brought into contact with the first pressure-sensitive adhesive layer of the first pressure-sensitive adhesive roll, and the first pressure-sensitive adhesive layer is contacted with the first pressure-sensitive adhesive layer. 2. The method for manufacturing an optical recording medium according to claim 1, wherein the foreign matter attached to the adhesive layer is transferred to the second adhesive layer. 4. The method according to claim 3, wherein the adhesive force of the second adhesive layer is larger than the adhesive force of the first adhesive layer. 5. The optical recording medium according to claim 3, wherein the adhesive force of the second adhesive layer is at least 3.5 times and at most 30 times the adhesive force of the first adhesive layer. Production method. 6. The adhesive force of the second adhesive layer is:
^{4. The} method for producing an optical recording medium according to claim ^{3, wherein the} density is from 6.86 × 10 ³ N / m ^{2 to} 1.96 × 10 ⁴ N / m ² . 7. The pressure-sensitive adhesive body is formed of a second pressure-sensitive adhesive roll having a columnar shape and the second pressure-sensitive adhesive layer provided on a side surface of a column, and the second pressure-sensitive adhesive roll has a roll diameter of the first pressure-sensitive adhesive. 4. The roll according to claim 3, wherein the roll diameter is larger than the roll diameter.
The production method of the optical recording medium according to the above. 8. The method for producing an optical recording medium according to claim 3, wherein the adhesive body is a belt-shaped adhesive belt having at least one surface provided with the second adhesive layer. 9. The light transmission layer is made of a material that can transmit a laser beam applied to the information signal layer at least when recording and / or reproducing the information signal. 2. The method for producing an optical recording medium according to item 1. 10. The method according to claim 1, wherein the physical vapor deposition method is a sputtering method or a vacuum deposition method.
The production method of the optical recording medium according to the above. 11. An optical recording medium in which at least an information signal layer is provided on a substrate, and the substrate is irradiated with light from the side on which the information signal layer is provided to record and / or reproduce an information signal. An apparatus for manufacturing an optical recording medium used for manufacturing an optical recording medium, comprising: a first pressure-sensitive adhesive roll having a cylindrical shape; and substrate holding means configured to hold the substrate, wherein a cylindrical side surface of the first pressure-sensitive adhesive roll is provided. A first pressure-sensitive adhesive layer, the first pressure-sensitive adhesive roll is configured to be able to contact the first pressure-sensitive adhesive layer with the exposed surface of the information signal layer, and An apparatus for manufacturing an optical recording medium, which is configured to be relatively movable. 12. The adhesive force of the first adhesive layer is 6.8.
The optical recording medium manufacturing apparatus according to claim 11, wherein the optical recording medium is at least 6 × 10 ² N / m ^{2 and not} more than 1.96 × 10 ³ N / m ² . 13. An adhesive body provided with a second adhesive layer, wherein the first adhesive layer of the first adhesive roll and the second adhesive layer of the adhesive body are in contact with each other. 2. The apparatus according to claim 1, wherein the apparatus is configured to be capable of being used.
An apparatus for manufacturing an optical recording medium according to claim 1. 14. The adhesive force of the second adhesive layer is higher than the adhesive force of the first adhesive layer.
An apparatus for manufacturing the optical recording medium according to the above. 15. The adhesive force of the second adhesive layer is:
14. The apparatus for manufacturing an optical recording medium according to claim 13, wherein the optical recording medium is configured to have an adhesive strength of 3.5 to 30 times the adhesive force of the first adhesive layer. 16. The adhesive force of the second adhesive layer is 6.8.
14. The apparatus for manufacturing an optical recording medium according to claim 13, wherein the optical recording medium has a density of 6 × 10 ³ N / m ² or more and 1.96 × 10 ⁴ N / m ² or less. 17. The pressure-sensitive adhesive body according to claim 13, wherein the pressure-sensitive adhesive body comprises a second pressure-sensitive adhesive roll having a cylindrical shape, and the second pressure-sensitive adhesive layer is provided on a side surface of the second roll. For manufacturing optical recording media. 18. The roll diameter of the second adhesive roll is as follows:
18. The optical recording medium manufacturing apparatus according to claim 17, wherein the diameter of the first adhesive roll is larger than the diameter of the first adhesive roll. 19. The apparatus for manufacturing an optical recording medium according to claim 13, wherein the adhesive body is a belt-shaped adhesive belt having at least one surface provided with the second adhesive layer. 20. The light-transmitting layer is made of a material capable of transmitting at least a laser beam applied to the information signal layer when recording and / or reproducing the information signal. Item 12. An apparatus for manufacturing an optical recording medium according to Item 11.