JPH08293130A - Device for curing optical disk - Google Patents

Abstract

PURPOSE: To obtain a device for curing an optical disk in which a part of a UV-curing resin existing at the periphery of an optical disk is efficiently cured and the resin is uniformly cured as a whole. CONSTITUTION: This device for curing an optical disk consists essentially of a mounting table 7 on which a UV-curing resin is cured after 1st and 2nd resin substrates are stuck to each other with the UV-curing resin, a UV light source 12 disposed above the table 7 and reflecting members 15a, 15b, 18 arranged around the substrates. A built-up part of the UV-curing resin at the periphery of the resultant optical disk is efficiently cured and all the UV-curing resin of the optical disk can be uniformly cured.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk curing device, and more particularly, to an optical disk curing device for curing an ultraviolet curable resin interposed between two resin substrates of an optical disk with ultraviolet rays.

[0002]

2. Description of the Related Art Generally, an optical disc is one in which an information signal such as voice is transferred in the form of signal pits (signal holes) on one surface of a resin substrate such as polycarbonate as schematically shown in FIG. . A metal reflection film such as aluminum or nickel is provided on the signal surface, and a protection film such as an ultraviolet curable resin is formed on the metal reflection film to prevent damage.

To reproduce an optical disk, an objective lens is used on the signal surface to narrow the laser beam from the semiconductor laser, and the reflected light is received by a photodetector to reproduce the signal. Here, in order to obtain a higher density optical disc, it is effective that the thickness of the resin substrate is as thin as possible, but in reality, from the viewpoint of optical readout pickup efficiency and disc strength. A thickness of 0,6 mm is adopted.

However, with a resin substrate having such a thinness,
Mechanical strength is weak and it is easy to warp or bend. Therefore, by sticking the two sheets together, the total thickness is about 1.2 mm and the strength is secured. It can be said that a product with this thickness is versatile because it has a large amount of production at present and is almost the same as the standard for the thickness of a CDROM or the like to become the mainstream in the future.

As described above, the optical disk is formed by bonding the second resin substrate as a blank to the two resin substrates, that is, the first resin resin substrate to which high-density signals are transferred. In order to bond the two resin substrates together, first, an adhesive (for example, an ultraviolet curable resin) is applied to the joint surface of both resin substrates. After the adhesive is applied, the adhesive is cured by irradiating ultraviolet rays to obtain an optical disc in which two resin substrates are firmly integrated.

Here, the following problems have occurred when the adhesive is cured using ultraviolet rays. When one resin substrate is coated with the adhesive and the other resin substrate is joined, the adhesive is squeezed out from the outer peripheral portion between both resin substrates of the optical disk. Usually, the protruding adhesive that is in the form of a build-up is lightly pressed by a contact member and traced to form a uniform and uniform build-up portion.

Because of this built-up portion, even if the optical disk is dropped or bent carelessly, it is prevented from peeling off at the bonding portion. However, this built-up portion has a drawback that even if it is irradiated with ultraviolet rays from above the optical disk, the hardening is delayed and the hardening is insufficient. Insufficient curing greatly reduces the strength of the optical disc, and the quality of the product,
This will result in loss of reliability.

[0008]

SUMMARY OF THE INVENTION The present invention is intended to solve the above problems. That is, it is an object of the present invention to provide an optical disk curing device that can efficiently cure the ultraviolet curable resin in the portion existing on the outer peripheral side surface of the optical disk, and can evenly cure the entire surface.

[0009]

The inventors of the present invention have, in response to such problems, among the ultraviolet curable resins interposed between the two resin substrates, the ultraviolet curable resins existing on the outer peripheral portions of both resin substrates. As a result of earnest studies focusing on the point of efficiently curing the resin, it was found that the outer peripheral side surface portions of both resin substrates, which are difficult to cure by using the reflecting member, can be efficiently cured at the same time, and based on this finding The present invention has been completed.

That is, the present invention is: 1. An optical disk curing apparatus for bonding a first resin substrate and a second resin substrate via an ultraviolet curable resin and curing the resin on a mounting table. The apparatus for curing an optical disk includes a mounting table, an ultraviolet light source body disposed above the mounting table, and a reflecting member disposed around both the resin substrates.

2. An optical disk curing device in which a first resin substrate and a second resin substrate are bonded together via an ultraviolet curable resin, and the resin is cured on a mounting table, and a boss portion is provided in the center. And an optical disk curing device including a rotatable mounting table, an ultraviolet light source body disposed above the mounting table, and a reflecting member that reflects the light of the ultraviolet light source body and irradiates the outer peripheral side surfaces of the resin substrates. Exist in.

3. The curing device for the optical disc of the above-mentioned item 2, wherein the reflecting member is a plurality of divided reflecting mirrors arranged around the both resin substrates. 4. The curing device for the optical disc of the above-mentioned item 2, wherein the reflecting member is a continuous reflecting mirror arranged around the both resin substrates.

5. A curing device for an optical disc in which a first resin substrate and a second resin substrate are bonded together via an ultraviolet curing resin, and then the resin is cured on a mounting table, and a boss portion is provided in the center. An optical disk curing device comprising: a mounting table; a rotatable ultraviolet light source body disposed above the mounting table; and a reflecting member that reflects the light of the ultraviolet light source body and irradiates the outer peripheral side surfaces of both resin substrates. Exist.

6. The optical disk curing device of the above item 5, wherein the reflecting member is a plurality of divided reflecting mirrors arranged around the both resin substrates. 7. The above-mentioned optical disk curing apparatus of 5, wherein the reflecting member is a continuous reflecting mirror arranged around the both resin substrates.

[0015]

[Function] Both resin substrates adhered via the ultraviolet curable resin are placed on the mounting table, and while the mounting table or the ultraviolet light source body is rotated in this state, ultraviolet rays are applied to the ultraviolet curable resin between both resin substrates. Irradiate. Since the reflecting mirror is provided, the outer peripheral side surface of the bonded resin substrate is sufficiently irradiated with ultraviolet rays, and the ultraviolet curable resin is efficiently cured.

[0016]

The present invention will be described below with reference to the accompanying drawings. The optical disk manufacturing method of the present invention includes a step of molding a first resin substrate by an injection molding machine or the like using a stamper manufactured by a mastering step, and a molded first
A step of forming a reflective film and a protective film on the signal surface of the resin substrate,
The steps include the step of adhering the second resin substrate to the first resin substrate to integrate them. The optical disk curing device of the present invention is used in the final step of the bonding step in this optical disk manufacturing step.

Before explaining the optical disk curing apparatus, the step of bonding will be described as a precaution.
FIG. 5 is a schematic process showing the entire bonding process. (1)
In the step (1), the first resin substrate 2 having the signal surface formed on the upper surface of the rotatable mounting table 7 is positioned and mounted.

In the step (2), the ultraviolet curable resin is applied onto the first resin substrate 2. For example, while rotating the mounting table 7 at a low speed, the discharge nozzle 8 is moved from the outer periphery toward the center of the mounting table, and the ultraviolet ray curable resin is discharged from the discharge nozzle 8 to the first position.
It is applied to the upper surface of the resin substrate 2. By doing so, the ultraviolet curable resin is drawn in a spiral shape on the upper surface of the first resin substrate 2.

In the step (3), another second resin substrate 6 having no signal surface is placed on the first resin substrate 2 coated with the ultraviolet curable resin. In the step (4), the mounting table 7 is rotated at high speed (preferably 5000 rpm or more) in the superposed state. By this high speed rotation, the ultraviolet curable resin is spread between both resin substrates.
When the second resin substrate 6 is placed on the first resin substrate 2,
The air that has entered between the resin substrates 1 and the air bubbles originally contained in the ultraviolet curable resin itself are discharged.

If the ultraviolet curable resin is spirally applied, the air will be discharged to the outside along the spiral guide path. At this time, the ultraviolet curable resin protruding from both resin substrates together with air and air bubbles,
It remains attached to the outer peripheral side surfaces of both resin substrates as it is in a state of being built up. As described above, normally, the abutment member is applied to the padding portion to average the padding portion over the entire circumference.

In the step (5), while the resin substrates 1 bonded to each other on the mounting table are rotated, ultraviolet rays are irradiated to cure the ultraviolet curable resin. Here, the light emitted from the ultraviolet light source body 12 and the ultraviolet light source body 12
The light rays reflected by the concave rear reflecting mirror 13 provided on the back of the resin are irradiated to the ultraviolet curable resin of both resin substrates 1. The optical disk curing apparatus of the present invention is positioned in the step (5) of all the bonding steps described above.

Here, the optical disk curing device will be described with reference to the drawings. First, the first embodiment in which the reflecting member is a divided reflecting mirror will be described. FIG. 1A is an explanatory diagram showing a state where the optical disc is irradiated with ultraviolet rays.
Further, FIG. 1B is a perspective view of FIG. 1A (the ultraviolet light source body is omitted). The optical disk curing device is mainly composed of a mounting table 7 having a boss portion 14 in the center, an ultraviolet light source 12, and reflecting mirrors 15a and 15b as reflecting members.

The mounting table 7 is rotatably supported by a rotary shaft 16 and has an upper surface on which an adsorption surface 1 for adsorbing both resin substrates 1 is attached.
7 are formed. As described above, the boss 4 is provided at the center of the suction surface 17, and the optical disc is accurately positioned on the mounting table 7 by inserting the center hole of the resin substrate 1 into the boss 4. To be done. Further, the ultraviolet light source body 12 is a long cylindrical body provided with a concave rear reflecting mirror 13 on the back side, and has a shape similar to a commonly used fluorescent lamp.

The ultraviolet light source 12 is arranged directly above the mounting table 7 so as to cross the suction surface 17. The concave rear reflecting mirror 13 receives the light emitted rearward from the ultraviolet light source body 12, reflects it, and irradiates it on the resin substrate 1 which is attached. On the other hand, the reflecting mirrors 15a and 15b are
A pair of rectangular flat reflecting mirrors surround the mounting table 7 and are arranged on both sides of the mounting table 7 in an inclined state (for example, 45 degrees).
By the pair of flat reflecting mirrors 15a and 15b, a part of the light obliquely emitted from the ultraviolet light source body 12 is reflected toward the ultraviolet curable resin which is built up on the outer peripheral side surfaces of both resin substrates 1. You can

A curing procedure by ultraviolet rays using the flat reflecting mirror described above will be described below. As shown in FIGS. 1A and 1B, when both resin substrates 1 are mounted on the suction surface 17 of the mounting table 7, the mounting table starts rotating at low speed (about 60 rpm). Therefore, light is emitted from the ultraviolet light source body 12. The radiated ultraviolet rays are radiated on the upper surfaces of both resin substrates 1, but the light directed backward is the concave rear reflecting mirror 13
Is reflected by and becomes a parallel light beam.
Is irradiated to the upper surface of the.

That is, the light emitted through the ultraviolet light source 12 or the concave rear reflecting mirror 13 is the first resin substrate 2
Transparent second resin substrate 6 placed on the upper surface of the substrate (see FIG. 6)
The ultraviolet-curing resin that passes through the resin and is present in the joint is irradiated. By the way, a part of the oblique light emitted from the ultraviolet light source body 12 is reflected by the pair of flat reflecting mirrors 15a and 15b arranged on both side surfaces of the mounting table 7 so as to be inclined,
The ultraviolet curable resin that is built up on the outer peripheral side surfaces of both resin substrates 1 is irradiated.

Therefore, the curing of the ultraviolet curable resin in the built-up portion is accelerated. In this case, the plane reflecting mirror 15
Since a and 15b are arranged around the resin substrate with a space therebetween, the light reflected from the a and 15b is applied only to a part of the outer peripheral surface of both resin substrates 1.

However, by rotating the mounting table 7 at a low speed, the reflected light is uniformly radiated over the entire outer peripheral side surface of the bonded resin substrate 1. In addition, although the pair of flat reflecting mirrors has been described as the above-described reflecting mirror, the present invention is not limited to this, and a large number of divided flat reflecting mirrors may be arranged at intervals.

Next, the second reflecting member is a continuous reflecting mirror.
Examples will be described. FIG. 2A is an explanatory diagram showing a state where the optical disc is irradiated with ultraviolet rays. Further, FIG. 2B is a perspective view of FIG. 2A (ultraviolet light source body is omitted). This curing device mainly has a boss portion 14 at the center.
A projection table 7, a UV light source body 12, and a continuous conical trapezoidal reflecting mirror 18 which is a reflecting member.

The conical trapezoidal reflecting mirror 18 has a shape in which the upper part thereof is opened and expanded with respect to the ultraviolet light source body 12. The mounting table 7 is rotatably supported by a rotary shaft 16, and a suction surface 17 that evenly sucks both resin substrates 1 is formed on the upper surface thereof. At the time of adsorption, a hole formed in the center of both resin substrates 1 is inserted into the boss portion 14 so that both resin substrates 1
Is reliably positioned on the mounting table 7.

The ultraviolet light source body 12 is formed of a long tubular body and is arranged so as to cross the mounting table 7. Behind the ultraviolet light source body 12 is a concave rear reflecting mirror 13.
The concave rear reflecting mirror 13 can irradiate the resin substrate 1 with the light emitted rearward from the ultraviolet light source body 12 as a vertical light beam. The truncated cone-shaped reflecting mirror 18 can reflect a part of the light obliquely emitted from the ultraviolet light source body 12 toward the ultraviolet curable resin which is built up on the outer peripheral side surfaces of the both resin substrates 1.

The procedure of curing with ultraviolet rays using the conical reflecting mirror 18 described above will be described below. As shown in FIGS. 2A and 2B, when both resin substrates 1 are mounted on the suction surface 17 of the mounting table 7, the mounting table 17 starts low speed rotation (usually about 60 rpm). . Therefore, light is emitted from the ultraviolet light source body 12. The radiated light is radiated to both resin substrates 1, and at the same time, the light directed rearward is reflected by the concave rear reflecting mirror 13 to become parallel rays.

Then, both resin substrates 1 are irradiated. That is,
The light emitted through the ultraviolet light source body 12 or the concave rear reflecting mirror 13 passes through the transparent second resin substrate 6 placed on the upper surface of the first resin substrate 2, and is interposed between both resin substrates 1. The UV curable resin is irradiated. On the other hand, the ultraviolet light source body 12
A part of the oblique light emitted from is reflected by the truncated cone-shaped reflecting mirror 18 and is accurately emitted to the entire outer peripheral side surfaces of both resin substrates 1. However, since the ultraviolet light source body 12 is formed in a long cylindrical body, the irradiation light is not uniformly applied to the conical reflecting mirror 18.

However, by rotating the mounting table 7, it is possible to uniformly irradiate the ultraviolet curable resin between both resin substrates with each other, so that the built-up portions on the entire outer peripheral surfaces of both resin substrates are covered. Can also be irradiated uniformly. In this way, both resin substrates 1 mounted on the mounting table 7 have the ultraviolet light source body 12
It is possible to reliably irradiate a part of the light emitted from the UV-curable resin, which is built up on the outer peripheral side surfaces of both resin substrates, by using a reflecting mirror. The hardening of the built-up portions on the outer peripheral side surfaces of both resin substrates, which are hard to be hardened, is promoted, and the entire both resin substrates are uniformly hardened.

Next, another third embodiment will be described. FIG. 3 is an explanatory diagram showing a state in which the optical disc is irradiated with ultraviolet rays. In the above-described first embodiment, an example in which the mounting table 7 rotates has been described, but in this embodiment, the mounting table 7 is fixed and the ultraviolet light source body 12 is rotated. That is, since the ultraviolet light source 12 and the concave rear reflecting mirror 13 are integrally formed, the ultraviolet light source 12 is also rotated by rotating the rotating shaft 20 of the concave rear reflecting mirror 13 at a low speed.

By the rotation of the ultraviolet light source body 12, the ultraviolet curable resin between both resin substrates is irradiated with light evenly. Further, the UV curable resin that is built up on the outer periphery between the two resin substrates is also effectively irradiated with the light reflected by the flat reflecting mirrors 15a and 15b that are the reflecting members. Next, still another fourth embodiment will be described.

FIG. 4 is an explanatory diagram showing a state in which the optical disc is irradiated with ultraviolet rays. In the second embodiment described above, an example in which the mounting table 7 rotates has been described, but in the present embodiment,
The mounting table 7 is fixed and the ultraviolet light source 12 is rotated. Also in this case, by rotating the rotating shaft 20 and rotating the ultraviolet light source body 12, the ultraviolet curable resin between both resin substrates and the built-up portion on the outer peripheral side surface are more uniformly irradiated with light.

Although the present invention has been described above, it is needless to say that the present invention is not limited to the embodiments and various other modifications can be made without departing from the essence thereof. . For example, it is naturally possible to employ a plurality of long ultraviolet light source bodies for curing in view of irradiation efficiency. Further, for example, although the example in which the ultraviolet light source body is composed of a long cylindrical body has been described, the ultraviolet light source body may have a donut shape.

Further, the flat reflecting mirror can be used even if its mirror surface has a slight curvature. Also, the example in which the transparent second resin substrate is placed on the first resin substrate on which the signal surface is formed via the ultraviolet curable resin has been described, but this second resin substrate is the same as the first resin substrate. Even if the signal surface is provided in the above, it is naturally applicable. However, in this case, a special irradiation method is required because the metal reflection film blocks the transmission of ultraviolet rays.

[0040]

EFFECT OF THE INVENTION The ultraviolet curable resin on the built-up portion on the outer peripheral side surface of the optical disc can be efficiently cured, and the entire ultraviolet curable resin of the optical disc can be uniformly cured. As the ultraviolet curable resin is uniformly cured, the quality of the optical disc is improved and reliability can be obtained.

[Brief description of drawings]

FIG. 1A is an explanatory diagram showing a state in which an ultraviolet ray is applied to an optical disc in the first embodiment.
(B) is the perspective view (ultraviolet light source body is abbreviate | omitted).

FIG. 2A is an explanatory diagram showing a state in which ultraviolet rays are applied to the optical disc in the second embodiment.
(B) is the perspective view (ultraviolet light source body is abbreviate | omitted).

FIG. 3 is an explanatory diagram showing a state of irradiating the optical disc with ultraviolet rays in the third embodiment.

FIG. 4 is an explanatory diagram showing a state in which an optical disc is irradiated with ultraviolet rays in the fourth embodiment.

FIG. 5 is a schematic process drawing of bonding two resin substrates together.

FIG. 6 is a cross-sectional view of a bonded resin substrate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Laminated resin substrate (both resin substrates) 2 ... Resin substrate 6 ... Resin substrate 7 ... Mounting base 12 ... Ultraviolet light source body 13 ... Concave rear reflecting mirror 14 ... Boss part 15a, 15b ... Flat reflecting mirror 17 ... Adsorption surface 18 … Conical reflector

Claims (7)

[Claims] 1. An optical disk curing apparatus for bonding a first resin substrate and a second resin substrate via an ultraviolet curable resin and then curing the resin on a mounting table, the mounting table comprising:
A curing device for an optical disc, comprising: an ultraviolet light source body disposed above the mounting table; and a reflection member disposed around both the resin substrates. 2. A curing device for an optical disk, comprising: bonding a first resin substrate and a second resin substrate via an ultraviolet curable resin; and curing the resin on a mounting table. It is characterized by comprising a rotatable mounting table provided, an ultraviolet light source body disposed above the mounting table, and a reflecting member for reflecting the light of the ultraviolet light source body and irradiating the outer peripheral side surfaces of the both resin substrates. An optical disk curing device. 3. The optical disk curing device according to claim 2, wherein the reflecting member is a plurality of divided reflecting mirrors arranged around the both resin substrates. 4. The optical disk curing apparatus according to claim 2, wherein the reflecting member is a continuous reflecting mirror arranged around the both resin substrates. 5. An optical disk curing device for bonding a first resin substrate and a second resin substrate via an ultraviolet curable resin and curing the resin on a mounting table, wherein a boss portion is provided at the center. It is characterized by comprising a mounting table provided, an ultraviolet light source body which is disposed above the mounting table and is rotatable, and a reflection member which reflects the light of the ultraviolet light source body and irradiates the outer peripheral side surfaces of the both resin substrates. Hard disk curing device. 6. The optical disk curing device according to claim 5, wherein the reflecting member is a plurality of divided reflecting mirrors arranged around the both resin substrates. 7. The optical disk curing apparatus according to claim 5, wherein the reflecting member is a continuous reflecting mirror arranged around the both resin substrates.