JP2000276785A - Apparatus for production of optical recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accelerate the curing of a UV curing resin on the outer peripheral surface of a substrate. SOLUTION: This apparatus has a rotating section 11 which rotates a substrate 5 coated with the UV curing resin, a light source (UV ray emitting lamp) 14 which is disposed above the substrate 6 and irradiates the substrate 6 with UV rays 13 and an approximately toric light reflector 15 which is disposed on the outer side of the outer peripheral surface of the substrate 6. The reflection surface 15a of the UV rays 13 is formed as a curved surface in the light reflector 15 and the outer peripheral surface of the substrate 6 is irradiated with the UV rays 13 reflected by the reflection surface 5a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for manufacturing an optical recording medium suitable for curing an ultraviolet curable resin applied to a substrate serving as an optical recording medium. The present invention relates to an optical recording medium manufacturing apparatus suitable for forming a protective film by applying a cured resin, or bonding a pair of substrates to be an optical recording medium via an ultraviolet curable resin applied as an adhesive. .

[0002]

2. Description of the Related Art As an optical recording medium, a disk-shaped optical disk on which optical recording and / or reproduction is performed has been put to practical use. Generally, in an optical disk, as typified by a compact disk (CD), for example, a fine concave (pit) pattern indicating an information signal is formed in a track direction on a transparent substrate made of polycarbonate or the like. Forming a recording layer on which a reflective film made of aluminum or the like is formed on the substrate on which the pit pattern is formed,
In order to prevent corrosion and damage of the recording layer, a protective film made of an ultraviolet curable resin is formed.

Recently, a digital video disc (DVD) capable of storing one movie on a disc having the same diameter as a CD and having a diameter of 120 mm with the same image quality as that of a current television has been developed. This optical disc has a double-plate structure in which a pair of substrates are bonded via an ultraviolet-curable resin applied as an adhesive in order to cope with high recording density, instead of the single-plate structure described above.

When producing these optical disks, a protective film made of an ultraviolet-curable resin is formed on a substrate as described above, or a pair of substrates is coated with an ultraviolet-curable resin applied as an adhesive. And are stuck together. Then, the ultraviolet curable resin as the protective film or the adhesive is applied by using a so-called spin coating method.

For example, when a protective film is formed by the spin coating method, an optical recording medium manufacturing apparatus 100 as shown in FIG. 9 is used. In this manufacturing apparatus 100,
First, the disk substrate 101 on which the recording layer is formed is placed on a turntable 102 and rotated at a low speed by a spindle motor. Then, the ultraviolet curable resin 103 is supplied in a substantially annular shape along the inner peripheral portion of the recording area of the disk substrate 101. Next, the disk substrate 101 is rotated at a high speed, and the ultraviolet curable resin 103 is extended to the outer peripheral portion by centrifugal force. Then, a coating film of the ultraviolet curable resin 103 is formed over the entire surface of the disk substrate 101. afterwards,
The protective film is formed on the disk substrate 101 by irradiating the ultraviolet light emitting lamp 104 with ultraviolet rays 105 to cure the coating film of the ultraviolet curing resin 103.

Further, by using the manufacturing apparatus 100, a pair of substrates bonded together via the above-mentioned ultraviolet curable resin can be manufactured.

[0007]

In the conventional optical recording medium manufacturing apparatus 100 described above, the disk substrate 1
01 is rotated at high speed, and the ultraviolet curable resin 1 is centrifuged.
03 is extended to the outer periphery, the disk substrate 1
In this state, the ultraviolet curable resin 103 protrudes from the outer peripheral surface 101a of the light emitting device 01.

[0008] For example, as shown in FIG.
In the case of the protective film 107 formed thereon, it hardens in a state of hanging from the outer peripheral surface 106a of the disk substrate 106. Also, as shown in FIG. 3B, when the protruding ultraviolet curable resin 103 is the adhesive 109 for bonding the pair of disk substrates 108, the ultraviolet curable resin 103 is raised on the outer peripheral surfaces 108a of the pair of disk substrates 108. To cure.

In this manufacturing apparatus 100, as shown in FIG. 9, an ultraviolet light emitting lamp 10 is used to cure an ultraviolet curing resin 103 applied on a disk substrate 101.
4, ultraviolet rays 105 are emitted so as to be substantially perpendicular to the main surface of the disk substrate 101.

For this reason, the outer peripheral surface 1 of the disk substrate 101
In the case of 01a, the efficiency of receiving the ultraviolet rays 105 with respect to the ultraviolet curable resin 103 protruding from the outer peripheral surface 101a is poor, and there is a problem that the protruding ultraviolet curable resin 103 cannot be completely cured. The protruding ultraviolet curable resin 103 has a tendency to harden because it is formed in a build-up shape.

Therefore, in this manufacturing apparatus 100, FIG.
As shown in FIG. 1, as a method of curing the ultraviolet curable resin 103 protruding from the outer peripheral surface 101a of the disk substrate 101, a light reflector 110 is disposed outside the outer peripheral surface 101a of the disk substrate 101, and the light reflector 110 A method has been proposed in which ultraviolet rays 105 emitted from above the substrate 101 are reflected and emitted to the outer peripheral surface 101a of the disk substrate 101.

More specifically, the light reflector 110 has a substantially annular shape whose inner diameter is larger than the outer diameter of the disc substrate 101, and has an outer peripheral surface 101 a of the disc substrate 101 mounted on the turntable 102. Placed outside the Also,
As shown in FIG. 12, the light reflector 110 has a reflecting surface 110 a for reflecting the ultraviolet light 105 radiated from the ultraviolet light emitting lamp 104.
The slope is 5 °. Therefore, the ultraviolet light 105 radiated so as to be substantially perpendicular to the main surface of the disk substrate 101 is applied to the reflection surface 110 a of the light reflector 110.
, And is irradiated substantially perpendicularly to the outer peripheral surface 101a of the disk substrate 101.

However, in the light reflector 110, since the reflecting surface 110a is formed as an inclined surface having a certain angle, the ultraviolet light reflected by the reflecting surface 110a has an area y equal to the thickness x of the disk substrate. Only the reflected ultraviolet light can be applied to the outer peripheral surface 101a of the disk substrate 101.

For this reason, the conventional optical recording medium manufacturing apparatus 1
00, even when such a light reflector 110 is disposed, the ultraviolet curable resin 103 protruding from the outer peripheral surface 101a of the disk substrate 101 cannot be completely cured, and the main surface of the disk substrate 101 In some cases, there was a delay in curing between the UV-curable resin 103 and the applied UV-curable resin 103.

As described above, the uncured ultraviolet-curing resin 103 is used in a later step to form the disk substrate 101.
Contacting the outer peripheral surface 101a of the device not only contaminates the contact person and the contacted device, but also causes defective products, which leads to a significant reduction in product yield.

As a method for solving this problem, it is conceivable to increase the photocuring sensitivity of the ultraviolet curable resin 103. However, the ultraviolet curable resin 103 protruding from the outer peripheral surface 101a of the disk substrate 101 and the main part of the disk substrate 101 This does not solve the delay in curing the UV curable resin 103 applied on the surface to the coating film, and there is naturally a limit. When the photocuring sensitivity of the UV-curable resin 103 is increased, the UV-curable resin 103 is cured before being supplied onto the disk substrate 101, or is being coated on the disk substrate 101. May be cured.

As a method for solving this problem, a method of adding an ultraviolet light emitting lamp can be considered, but this leads to an increase in manufacturing cost.

Accordingly, the present invention has been proposed in view of such conventional circumstances, and is an apparatus for manufacturing an optical recording medium suitable for curing an ultraviolet curable resin applied to a substrate serving as an optical recording medium. For the purpose of providing, for example,
A protective film may be formed by applying an ultraviolet curable resin on a substrate serving as an optical recording medium, or a pair of substrates serving as an optical recording medium may be bonded via an ultraviolet curable resin applied as an adhesive. It is an object of the present invention to provide a suitable optical recording medium manufacturing apparatus.

[0019]

According to a first aspect of the present invention, there is provided an optical recording medium manufacturing apparatus comprising: a rotating unit configured to rotate a substrate coated with an ultraviolet curable resin; A light source that irradiates ultraviolet rays to the light source, and a substantially annular light reflector disposed outside the outer peripheral surface of the substrate,
The light reflector is characterized in that the reflection surface of the ultraviolet light has a curved surface, and the ultraviolet light reflected on the reflection surface is applied to the outer peripheral surface of the substrate.

In the apparatus for manufacturing an optical recording medium according to the present invention configured as described above, since the reflecting surface of the light reflector for reflecting the ultraviolet light is curved, the ultraviolet light reflected by the reflecting surface is applied to the substrate. Is condensed on the outer peripheral surface. For this reason, in this manufacturing apparatus, the irradiation efficiency of the ultraviolet light irradiated to the outer peripheral surface of the substrate is improved, and the curing of the ultraviolet curable resin on the outer peripheral surface of the substrate is promoted.

Further, it is preferable that the light reflector is made of aluminum.

In this case, the ultraviolet rays applied to the reflection surface of the light reflector can be efficiently reflected to the outer peripheral surface of the substrate.

The light reflector is made of stainless steel,
An aluminum foil having a light reflectance of 80% or more may be attached to the reflection surface.

In this case, the ultraviolet rays applied to the reflection surface of the light reflector can be efficiently reflected to the outer peripheral surface of the substrate.

[0025]

Embodiments of the present invention will be described below in detail with reference to the drawings.

As shown in FIG. 1, the optical recording medium to be manufactured in this embodiment is an optical disk 1 having a protective film formed by applying an ultraviolet curable resin on a substrate to be an optical recording medium. .

As shown in FIGS. 1 and 2, this optical disc 1 has, for example, a pit pattern indicating an information signal on a transparent substrate 3 made of polycarbonate or the like having a center hole 2 at the center and formed in a disk shape. Is formed in the track direction, a reflection film made of aluminum or the like is formed on the substrate 3 on which the pit pattern is formed to form a recording layer 4, and a protective film made of an ultraviolet curable resin is formed on the recording layer 4. 5
Is formed.

In the optical disk 1, the recording layer 4
Is used as a recording film such as a phase-change recording film, an organic dye film, a magneto-optical recording film, etc., thereby making it possible to obtain an optical disk capable of reproducing, additionally writing, and rewriting.

In this optical disc 1, the protective film 5
The film is formed using a so-called spin coating method. For example,
When forming the protective film 5 by the spin coating method, first, the substrate 3 on which the recording layer 4 is formed is placed on a turntable and rotated at a low speed by a spindle motor. Then, the ultraviolet curable resin is supplied in a substantially annular shape along the inner peripheral portion of the recording area of the substrate 3. Next, the substrate 3 is rotated at a high speed, and the ultraviolet curable resin is stretched to the outer peripheral portion by centrifugal force. Then, an ultraviolet curable resin coating film having a substantially uniform film thickness is formed over the entire surface of the substrate 3. Thereafter, the protective film 5 is formed on the substrate 3 by irradiating the ultraviolet curable resin coating film with ultraviolet light from an ultraviolet light emitting lamp to cure the resin film.

In the optical disc 1, a protective film 5 is formed on the substrate 3 on which the recording layer 4 is formed with high precision by using an optical recording medium manufacturing apparatus 10 to which the present invention is applied as shown in FIG. Can be membrane. In the following description, the substrate 3 on which the recording layer 4 is formed is simply referred to as a disk substrate 6.

The apparatus 10 for manufacturing an optical recording medium comprises a rotating unit 11 for rotating the disk substrate 6,
An ultraviolet light emitting lamp 14 for irradiating ultraviolet rays 13 to the disk substrate 6 coated with the light emitting element 2, and a light reflector 15 for reflecting the ultraviolet light 13 emitted from the ultraviolet light emitting lamp 14 toward the outer peripheral surface 6 a of the disk substrate 6. And

The rotating unit 11 includes a turntable 16 on which the disk substrate 6 is mounted, a rotating shaft 17 that supports the turntable 16, a spindle motor that drives the rotating shaft 17 to rotate at a predetermined rotation speed, and have.

The turntable 16 has a boss 18 projecting from the center thereof.
The disc substrate 6 is accurately positioned by fitting the center hole 2 of the disc.

The ultraviolet light emitting lamp 14 is disposed above the turntable 16 and irradiates the disk substrate 6 mounted on the turntable 16 with ultraviolet light 13 so as to be substantially vertical.

As shown in FIGS. 3 and 4, the light reflector 15 has a substantially annular shape whose inner diameter is larger than the outer diameter of the disc substrate 6, and the disc substrate 6 mounted on the turntable 16. Is arranged so as to cover the outside of the outer peripheral surface 6a. The light reflector 15 has a curved reflecting surface 15a for reflecting the ultraviolet light 13 emitted from the ultraviolet light emitting lamp.

As the light reflector 15, it is preferable to use a material having high light reflection efficiency, for example, it is preferable to use aluminum. Thereby, the ultraviolet light 13 irradiated on the reflection surface 15a of the light reflector 15 can be efficiently reflected. In addition, as aluminum, JI
S1050 to JIS1085.

In the light reflector 15, stainless steel is used as a base material, and the light reflectance is 80% on the reflection surface 15a.
The above-described aluminum foil may be attached. Thus, similarly to the above-described light reflector made of aluminum, the ultraviolet light 13 applied to the reflection surface 15a of the light reflector 15 can be efficiently reflected.

In the optical recording medium manufacturing apparatus 10 configured as described above, the disk substrate 6 on which the coating film of the ultraviolet curable resin 12 is formed is irradiated with ultraviolet light 13 from above by the ultraviolet light emitting lamp 14.

Here, in the optical recording medium manufacturing apparatus 10,
As shown in FIG. 5, the reflection surface 15a of the light reflector 15 is a curved surface.

In this case, the optical recording medium manufacturing apparatus 10
Thus, the ultraviolet light 13 reflected on the reflection surface 15a of the light reflector 15 can be focused on the outer peripheral surface 6a of the disk substrate 6. That is, in the optical recording medium manufacturing apparatus 10,
When the thickness of the disk substrate 6 is s, this reflecting surface 15
Of the ultraviolet light 13 reflected by a, the ultraviolet light 13 reflected from an area t wider than the thickness s of the disk substrate 6 can be applied to the outer peripheral surface 6a of the disk substrate 6.

On the other hand, when the reflecting surface of the conventional light reflector is formed as a slope having a certain angle, the ultraviolet light reflected by the reflecting surface has an area equal to the thickness of the disk substrate. Only the ultraviolet light reflected from the disk substrate can be applied to the outer peripheral surface of the disk substrate.

As described above, in the optical recording medium manufacturing apparatus 10, the ultraviolet rays 1
The irradiation efficiency of the ultraviolet curable resin 12 protruding from the outer peripheral surface 6a of the disk substrate 6 can be greatly improved.
Can promote curing.

Therefore, this optical recording medium manufacturing apparatus 1
In the case of 0, curing delay occurs between the ultraviolet curable resin 12 protruding from the outer peripheral surface 6a of the disk substrate 6 and the coating film of the ultraviolet curable resin 12 applied on the main surface of the disk substrate 6. Can be prevented.

Further, in the optical recording medium manufacturing apparatus 10, the ultraviolet curable resin 12 protruding from the outer peripheral surface 6a of the disk substrate 6 can be completely cured. Face 6
a can be directly touched by hand. Therefore, a visual inspection can be easily performed, and the curing of the ultraviolet curable resin 12 can be confirmed in the manufacturing process. Therefore, a high-quality optical disk with improved reliability can be manufactured, and the safety can be improved without contaminating a contact person or an apparatus.

Further, in the optical recording medium manufacturing apparatus 10, the ultraviolet curable resin 12 protruding from the outer peripheral surface 6 a of the disk substrate 6 without adding the ultraviolet light emitting lamp 14.
Can be cured.

In the light reflector 15, the reflection surface 1
By making the surface 5a a curved surface, the ultraviolet light 13 reflected by the reflecting surface 15a has a focal point O. The focal point O of the ultraviolet light is placed on the outer peripheral surface 6a of the disk substrate 6, or
Alternatively, regarding whether the focal point O is located before or after the outer peripheral surface 6a,
It is preferable that the value be determined based on the state of protrusion of the ultraviolet curable resin 12 applied to the disk substrate 6. That is, in the light reflector 15, it is determined whether the outer peripheral surface 6a of the disk substrate 6 is irradiated with the ultraviolet rays 12 condensed and emitted at a point or the ultraviolet rays 12 are irradiated with a certain surface. It is preferable that the value be determined based on the state of protrusion of the ultraviolet curable resin 12 applied to the substrate 6.

The curvature of the reflecting surface 15a of the light reflector 15 is preferably determined by drawing from the relationship between the height of the reflecting surface 15a, the distance from the disk substrate 6, and the focal point O.

As described above, the optical recording medium manufacturing apparatus 10 can form a protective film on the disk substrate 6 with high accuracy, and can manufacture a high-quality optical disk with improved reliability. it can.

Next, another optical recording medium to be manufactured in this embodiment is shown in FIG.

This optical recording medium is an optical disk 20 in which a pair of substrates serving as an optical recording medium are bonded together via an ultraviolet curable resin applied as an adhesive. As shown in FIGS. 6 and 7, the optical disc 20 has a center hole 2 at the center.
For example, a pit pattern indicating an information signal is formed in the track direction on a transparent first substrate 22 made of polycarbonate or the like, which has a disk shape having 1, and on the first substrate 22 on which the pit pattern is formed. , A reflective film made of aluminum or the like is formed to form a recording layer 23, and a transparent second substrate 25 made of polycarbonate or the like is bonded via an ultraviolet curable resin 24 applied on the recording layer 23. Become.

In the optical disc 20, the recording layer 23 is formed of a recording film such as a phase change recording film, an organic dye film, a magneto-optical recording film, etc. it can. The optical disc 20 can be a double-sided optical disc by forming a recording layer on the second substrate.

In this optical disc 20, for example, the first substrate 22 and the second substrate 25 are
First, the first substrate 22 placed on the turntable is rotated at a low speed by the spindle motor. Then, the ultraviolet curable resin 24 is supplied in a substantially annular shape along the inner peripheral portion of the recording area of the first substrate 22. Next, the first UV-curable resin 24
The second substrate 25 is placed on the substrate 22 of FIG. Then, the superimposed first substrate 22 and second substrate 25 are rotated at a high speed, and the ultraviolet curable resin 24 is stretched to the outer peripheral portion by centrifugal force. Then, a coating film of the ultraviolet curable resin 24 is formed over the entire surface between the first substrate 22 and the second substrate 25. Thereafter, the first substrate 22 and the second substrate 25 are bonded to each other through the ultraviolet curable resin 24 by irradiating the ultraviolet curable resin 24 with ultraviolet light from the ultraviolet light emitting lamp to cure the coating. .

In the optical disk 20, the first substrate 2 is formed by using the above-described optical recording medium manufacturing apparatus 10.
2 and the second substrate 25 can be bonded with high precision via the ultraviolet curable resin 24 applied as an adhesive. In the following description, the first substrate 22 and the second substrate bonded together by the ultraviolet curing resin 24 are simply referred to as a pair of disk substrates 26.

In this case, the optical recording medium manufacturing apparatus 10 irradiates the pair of disk substrates 26 mounted on the turntable 16 with ultraviolet rays 13 from above by the ultraviolet light emitting lamps 14. At this time, in the optical recording medium manufacturing apparatus 10, since the reflection surface 15a of the light reflector 15 is curved as shown in FIG.
The ultraviolet light 13 reflected by the a
Can be condensed on the outer peripheral surface 26a.

As described above, in the optical recording medium manufacturing apparatus 10, similarly to the above-described optical disk 1, the irradiation efficiency of the ultraviolet light 13 irradiating the outer peripheral surfaces 26 a of the pair of disk substrates 26 can be greatly improved. The curing of the ultraviolet curable resin 24 protruding from the outer peripheral surfaces 26a of the pair of disk substrates 26 can be promoted.

Therefore, this optical recording medium manufacturing apparatus 1
0, the ultraviolet curable resin 24 protruding from the outer peripheral surfaces 26 a of the pair of disk substrates 26 and the ultraviolet curable resin 2 formed over the entire surface between the pair of disk substrates 26.
4 can be prevented from being delayed with respect to the coating film No. 4.

As described above, the optical recording medium manufacturing apparatus 10 sets the pair of disk substrates 26 on the ultraviolet curable resin 24.
And a high-quality optical disc with improved reliability can be manufactured.

[0058]

As described in detail above, in the apparatus for manufacturing an optical recording medium according to the present invention, since the reflecting surface of the light reflector for reflecting ultraviolet rays is curved, the light is reflected by the reflecting surface. Ultraviolet rays can be focused on the outer peripheral surface of the disk substrate. For this reason, in this manufacturing apparatus, the irradiation efficiency of the ultraviolet light radiated to the outer peripheral surface of the disk substrate can be greatly improved, and the curing of the ultraviolet curable resin on the outer peripheral surface of the disk substrate can be promoted. Therefore, according to this manufacturing apparatus, a high-quality optical recording medium with improved reliability can be manufactured.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one configuration example of an optical recording medium to be manufactured according to the present invention.

FIG. 2 is a cross-sectional view of a principal part schematically showing a configuration of the optical recording medium.

FIG. 3 is a schematic side view showing a configuration of an optical recording medium manufacturing apparatus to which the present invention is applied.

FIG. 4 is a schematic perspective view showing a configuration of the manufacturing apparatus.

FIG. 5 is a diagram showing a state in which an outer peripheral surface of a disk substrate is irradiated with ultraviolet rays.

FIG. 6 is a perspective view showing another configuration example of an optical recording medium to be manufactured according to the present invention.

FIG. 7 is a cross-sectional view of a principal part schematically showing a configuration of the optical recording medium.

FIG. 8 is a diagram showing a state in which the outer peripheral surfaces of a pair of disk substrates are irradiated with ultraviolet rays.

FIG. 9 is a schematic side view showing a configuration of a conventional optical recording medium manufacturing apparatus.

10A and 10B are diagrams showing a state in which the ultraviolet curable resin has protruded from the outer peripheral surface of the disk substrate. FIG. 10A shows a case where the protruded ultraviolet curable resin is a protective film formed on the disk substrate, and FIG. FIG. 4 is a diagram showing a case where the protruding ultraviolet curable resin is an adhesive for bonding a pair of disk substrates.

FIG. 11 is a diagram showing a state where a light reflector is arranged in a conventional optical recording medium manufacturing apparatus.

FIG. 12 is a diagram showing a state in which an outer peripheral surface of a disk substrate is irradiated with ultraviolet rays.

[Explanation of symbols]

1 optical disk, 5 protective film, 6 disk substrate, 6a
Outer peripheral surface of disk substrate, 10 optical recording medium manufacturing device, 12 ultraviolet curable resin (protective film), 13 ultraviolet light,
14 ultraviolet light emitting lamp, 15 light reflector, 15a reflecting surface of light reflector, 16 turntable, 20 other optical disks, 24 ultraviolet curing resin (adhesive), 26 pair of disk substrates

Claims (5)

[Claims] A rotating unit configured to rotate a substrate coated with an ultraviolet curable resin, a light source disposed above the substrate and irradiating the substrate with ultraviolet light, and a light source disposed outside an outer peripheral surface of the substrate. A substantially annular light reflector, wherein the light reflector has a curved reflecting surface for reflecting the ultraviolet light, and the ultraviolet light reflected on the reflecting surface is applied to the outer peripheral surface of the substrate. Characteristic optical recording medium manufacturing apparatus. 2. The optical recording medium manufacturing apparatus according to claim 1, wherein a substrate having one main surface coated with an ultraviolet curable resin is placed on the rotating section. 3. An apparatus for manufacturing an optical recording medium according to claim 1, wherein a pair of substrates bonded by an ultraviolet curable resin is placed on said rotating section. 4. The apparatus according to claim 1, wherein said light reflector is made of aluminum. 5. The light according to claim 1, wherein the light reflector is made of stainless steel, and an aluminum foil having a light reflectance of 80% or more is attached to the reflection surface. Manufacturing equipment for recording media.