JP2002338902A - Adhesive method for part member and manufacturing method of disc and unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate squeezing out of an ultraviolet curing composition and generation of gap between disc substrates by improving coating accuracy of the ultraviolet curing composition to adhering surfaces. SOLUTION: In a manufacturing method for a disc which is obtained by bonding together two disc substrates 1a and 1b with the cation type ultraviolet curing composition as an adhesive, a process wherein the cation type ultraviolet curing composition is coated on a part of the bonding surface of the disc substrate 1a, a process wherein ultraviolet rays are irradiated to the coated cation type ultraviolet curing composition S, a process wherein the disc substrates 1a and 1b are bonded together via the cation type ultraviolet curing composition irradiated with the ultraviolet rays, and a process wherein the cation type ultraviolet curing composition which exists between the disc substrates 1a and 1b is spread, are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bonding method for bonding two members to be bonded with a cationically polymerizable UV-curable composition as an adhesive, and further relates to a method for bonding two disk substrates to a cationically polymerizable UV curable composition. TECHNICAL FIELD The present invention relates to a disk manufacturing method and a disk manufacturing apparatus in which a conductive composition is bonded as an adhesive to form one disk.

[0002]

2. Description of the Related Art Conventionally, as a method of bonding various members such as plastic parts, for example, a method using an adhesive such as a hot-melt adhesive, a solvent-based adhesive, or an ultraviolet-curable composition, or a heat-sealing method is used. Are mainly used.

For example, when manufacturing a digital video / versatile disk, so-called DVD,
A technique has been adopted in which two disk substrates are attached to each other using an ultraviolet curable composition or the like as an adhesive. The ultraviolet curable composition referred to herein includes at least a cationic polymerization type ultraviolet curable composition and a radical polymerization type ultraviolet curable composition. Cationically polymerizable UV-curable compositions do not cure immediately after UV irradiation and have a slow-acting property, which cures after a predetermined time, whereas radical UV-curable compositions have a fast-acting property, which cures immediately after UV irradiation. It is. The latter radically polymerizable UV-curable composition has a structure in which two disc substrates to be laminated are UV-transparent, for example, DVD-R.
In the case of OM or the like, since a disk substrate can be preliminarily bonded with an ultraviolet curable composition therebetween and then irradiated with ultraviolet light through the substrate, it can be used as an adhesive for disk bonding. In the case where the two disk substrates to be bonded do not transmit ultraviolet light at all, it is difficult to apply the adhesive as a bonding adhesive because ultraviolet light cannot be irradiated after bonding. On the other hand, the former cationically polymerizable UV-curable composition has a slow curing speed, so that UV irradiation can be performed in advance before the disk substrates are bonded together. Is possible.

[0004] In order to attach two disk substrates that do not transmit ultraviolet light by using a cationic polymerization type ultraviolet curable composition as an adhesive, first, the ultraviolet curable composition is applied to at least one of the disk substrates. 2 across this
The two disk substrates are overlapped.

[0005] The timing of the ultraviolet irradiation must be before the two disk substrates are overlaid. As one of such methods, there is a method of irradiating an ultraviolet curable composition with ultraviolet light before coating. Specifically, there is a method in which a cationic polymerization type ultraviolet curable composition is discharged from a nozzle, dropped in the air, and applied in a circle on a bonding surface of one disk substrate. At this time, the ultraviolet irradiation to the cationic polymerization type ultraviolet curable composition is performed in a space where the ultraviolet curable composition falls from the tip of the nozzle and reaches the disk substrate.

[0006]

By the way, regarding the bonding method using an adhesive such as a hot-melt adhesive or a solvent-based adhesive, depending on the use of the member to be bonded, the heat resistance is poor or the bonding strength or bonding accuracy is low. In addition to being difficult to come out, there were also problems such as a long bonding time and poor workability.

On the other hand, as to the above-mentioned bonding of a disk substrate by drop irradiation of the cationic polymerization type ultraviolet curable composition, since direct ultraviolet irradiation is not performed on the disk substrate, information by heat from a light source is used. There is no need to consider the effect on the recording layer. Furthermore, by irradiating the ultraviolet ray to the falling path of the ultraviolet curable composition, it is possible to uniformly and sufficiently irradiate the entire ultraviolet curable composition. On the other hand, since the adhesive is dropped from a position considerably above the disk substrate, there is a problem in accuracy of application on the bonding surface. For example, the trajectory of the ultraviolet curable composition during the fall is disturbed by static electricity generated at a location adjacent to the fall trajectory,
It is not applied in the desired shape on the bonding surface, or a large mass of the ultraviolet-curable composition is formed in the portion that first reaches the bonding surface more than other portions, and is not uniformly applied in the circumferential direction. Or

[0008] As described above, when a disk substrate is bonded without accurately applying the ultraviolet-curable composition, the ultraviolet-curable composition protrudes from between the disk substrates, and conversely, the ultraviolet-curable composition becomes between the disk substrates. A gap may occur without spreading.

In order to prevent the occurrence of such a phenomenon, in a conventional disk manufacturing apparatus, the application amount of the ultraviolet curable composition is measured in advance and then applied, thereby improving the application accuracy. When a large number of disks are continuously produced, the above-mentioned phenomenon may occur, though rarely.

Therefore, a disk in which the ultraviolet curable composition protrudes or a disk in which a gap is formed between disk substrates is used.
We are working to find and remove using a visual inspection device. This makes it possible to almost completely remove the disk from which the ultraviolet curable composition has protruded.

However, at present, it is difficult to find a disk having a gap between disk substrates even by a visual inspection device. Since the gap between the disc substrates is formed on the inner or outer circumference of the disc, if the disc with the gap is used for a long period of time, moisture will infiltrate between the disc substrates and the durability will decrease. Reading and writing information to the disc may be hindered.

In addition, in the conventional disk manufacturing apparatus, while the production is continued for a long period of time, the vaporized ultraviolet curable composition adheres to the periphery of the fall trajectory (for example, the inner surface of the windproof tube covering the fall trajectory) and solidifies. However, there is also a problem that the ultraviolet curable composition is prevented from dropping.

On the other hand, there is also a method in which the ultraviolet-curable composition is uniformly applied to at least one of the disk substrates, or spread and spread, and then irradiated with ultraviolet light to bond the two disk substrates together. This method has an advantage that the ultraviolet-curable composition can be sufficiently and accurately spread before the ultraviolet irradiation, and that the spread composition can be irradiated with ultraviolet rays over a wide area. However, when bonding the members to be bonded after spreading, the surface of the applied and spread adhesive and the surface of the other disk are in contact with each other at the initial stage of bonding.
There is a drawback that trapped air bubbles are easily generated in the adhesive layer, and air bubbles once generated are difficult to be removed.

The present invention has been made in view of the above circumstances, and has a strong adhesive force when bonding two members to be bonded, for example, when bonding two disk substrates.
Adhesion extrudes and gaps between members to be bonded by enabling high-precision bonding, improving workability in a short time, and improving the application accuracy of the adhesive on the bonding surface. The purpose is to eliminate the generation of air bubbles and improve the product yield.

[0015]

Means for Solving the Problems In order to solve the above-mentioned problems, the present inventors have applied an ultraviolet-curable composition to at least one member to be bonded and then performed ultraviolet irradiation before spreading.
In the subsequent spreading step, the ultraviolet-curable composition can be spread sufficiently uniformly, and it is rather preferable to increase the coating accuracy. In addition, even if the coating is localized on the member to be bonded before being spread, even if the coating is irradiated with ultraviolet light, there is no problem with the spread or the hardening after the spread. The present inventors have found that it is preferable in terms of prevention of occurrence, and have completed the present invention.

As means for solving the above problems,
The present inventor has adopted a member bonding method, a disk manufacturing method, and a disk manufacturing apparatus having the following configurations. That is, the method for bonding members according to the present invention is a method for bonding two members to be bonded via an ultraviolet-curable composition, and the ultraviolet light is applied to a part of a bonded portion of one of the members to be bonded. A step of applying a curable composition, a step of irradiating the applied ultraviolet-curable composition with ultraviolet light, and the one member to be bonded and the other through the ultraviolet-curable composition irradiated with ultraviolet light. And a step of spreading the ultraviolet curable composition interposed between both the adherend members, and wherein the ultraviolet curable composition is a cationic polymerization type ultraviolet curable composition. It is characterized by being a thing.

According to this method of bonding members, the ultraviolet-curable composition is applied to the member to be bonded and then irradiated with ultraviolet light, so that the ultraviolet-curable composition is irradiated from a position close to the portion to be bonded. Composition can be applied. Therefore, the ultraviolet-curable composition can be applied to a predetermined site with high precision, and the protrusion of the ultraviolet-curable composition and the generation of gaps in the bonded product are prevented.

Further, after the ultraviolet curable composition applied to the member to be bonded is irradiated with ultraviolet rays, the ultraviolet curable composition is spread, whereby the bonding area between the two members to be bonded is increased, and strong bonding is achieved. A force is obtained and a high sealing effect is obtained.

Since the two members to be bonded are bonded in a state where the ultraviolet-curable composition is localized on the member to be bonded before spreading, the ultraviolet-curable composition localized between the members to be bonded is provided. The composition can be spread toward the end of the member while spreading the object. For this reason, air bubbles hardly remain between the members to be bonded.

Further, since the ultraviolet curable composition is of a cationic polymerization type, it takes a long time from irradiation of ultraviolet light to completion of curing. Accurate bonding can be performed while suppressing generation of bubbles.

Further, after the ultraviolet irradiation is performed in advance, one of the members to be bonded and the other member to be bonded are bonded via the ultraviolet curable composition, so that the time until the composition is cured after bonding is reduced. It can be shortened and both members can be bonded in a short time. Therefore, the time substantially required for the bonding step can be extremely short, so that the present invention can be applied to a continuous step and can contribute to improvement in productivity.

In the method for bonding members according to the present invention,
Wavelength region of cationically curable UV-curable composition 310 to 310
It is desirable that the light absorption coefficient at 340 nm is 2 × 10 ³ m ⁻¹ or less. In general, ultraviolet light having a wavelength of 370 nm or less is involved in photopolymerization of an ultraviolet curable composition,
A material having a large light absorption coefficient at 350 nm or less is used as a photopolymerization initiator. For this reason, in a general ultraviolet curable composition, 340 nm particularly contributing to polymerization is used.
Light absorption coefficient at wavelengths below is 1 × 10 ⁴ m ^- if it is in ^one or many. Here, the light absorption coefficient is a value represented by α in a relational expression I = I ₀ × 10 ^−αx between the incident light intensity I ₀ , the transmitted light intensity I, and the transmission distance x.

When the light absorption coefficient is 1 × 10 ⁴ m ⁻¹ , the transmission distance until the incident light intensity is reduced to 1/10 is
This means that there is only 0.1 mm, and most of the irradiated ultraviolet energy is absorbed by the surface. Therefore, curing occurs only at the surface portion, and a difference is created between the cured state of the surface and the inside, so that when the ultraviolet irradiation is performed as in the bonding method according to the present invention and spreading is performed, the ultraviolet curable composition is uniformly formed. It will cause it not to spread. On the other hand, if the light absorption coefficient is 2 × 10 ³ m ⁻¹ or less, the incident light is transmitted by 0.5 mm or more before attenuating to one-tenth, so that the ultraviolet energy is reduced to 5 times or more in volume. Thus, partial hardening due to the intensive absorption of only the surface as described above is unlikely to occur, and uniform spreading becomes possible. When a reactive species is implanted into the ultraviolet-curable composition in such a volume region by absorbing ultraviolet rays, the polymerization reaction extends to a portion where the reactive species cannot be formed due to insufficient transmission of ultraviolet rays. There is no problem in the curability of the adhesive layer after the elongation.

In the method for bonding members according to the present invention,
It is desirable to irradiate only the ultraviolet curable composition applied to the adhered portion with ultraviolet light. Since the member to be bonded may be damaged by the heat from the light source, only the ultraviolet curable composition applied to the bonded portion is irradiated with ultraviolet light, so that the member to be bonded is irradiated from the light source. Not affected by heat.

The method for bonding members according to the present invention can be suitably used for manufacturing disks. That is, the disk manufacturing method according to the present invention is a disk manufacturing method in which two disk substrates are bonded to each other by using an ultraviolet-curable composition as an adhesive to form one disk, and one disk substrate is bonded. A step of applying the ultraviolet-curable composition to part of the surface, a step of irradiating the applied ultraviolet-curable composition with ultraviolet light, and the ultraviolet-curable composition irradiated with ultraviolet light, The method includes a step of bonding one disk substrate and the other disk substrate, and a step of spreading the ultraviolet curable composition interposed between the two disk substrates.

According to this disk manufacturing method, the ultraviolet curable composition is applied to the disk substrate, and then the ultraviolet curable composition is irradiated with ultraviolet light. It is not necessary to drop from above the surface. Thereby, since the ultraviolet curable composition can be applied from a position closer to the bonding surface, disturbance of the drop trajectory does not occur, and application accuracy can be improved.
This prevents the ultraviolet curable composition from protruding between the disk substrates and the generation of gaps.

In the method for producing a disk according to the present invention, the ultraviolet curable composition is used in a wavelength range of 310 to 34.
At an arbitrary wavelength of 0 nm, the light absorption coefficient is 2 × 10 ³
It is desirably not more than m ⁻¹ . In the case of performing spreading after irradiation with ultraviolet rays as in the production method according to the present invention, if the light absorption coefficient of the ultraviolet curable composition is 2 × 10 ³ m ⁻¹ or less, intensive light absorption only on the surface is performed. Partial curing is unlikely to occur,
Uniform spreading becomes possible. As a result, the adhesive layer is formed uniformly between the disk substrates, and the protrusion of the ultraviolet curable composition and the generation of gaps between the disk substrates are prevented. In addition, when reactive species are planted not only on the surface of the UV-curable composition but also in the composition due to UV absorption, the polymerization reaction extends in a chain to the part where the reactive species cannot be formed due to insufficient transmission of UV rays. There is no worry about uneven curing.

In the disk manufacturing method according to the present invention, it is preferable that each of the disk substrates has a disk shape and the ultraviolet curable composition is applied to the disk substrate so as to form a concentric circle. If the UV-curable composition is applied concentrically to a disc-shaped disk substrate, the UV-curable composition spreads while maintaining the concentric shape in the radial direction by spreading, so that a uniform thickness of the adhesive is applied. The layer is formed, and the ultraviolet curable composition does not protrude from a part between the disk substrates, or does not spread out only partly, and a gap does not occur.

In the method of manufacturing a disk according to the present invention, it is desirable to irradiate only the ultraviolet curable composition applied to the bonding surface with ultraviolet light. The disc substrate is expected to be damaged by the information recording layer due to the heat from the light source. Therefore, by irradiating only the ultraviolet curable composition applied to the bonding surface with ultraviolet light, the information recording layer is not affected by heat from the light source.

In the method of manufacturing a disk according to the present invention, it is preferable that, during the spreading, the two disk substrates bonded together with the ultraviolet-curable composition interposed therebetween are rotated in the circumferential direction. When the two bonded disc substrates are rotated in the circumferential direction, the ultraviolet-curable composition interposed between the disc substrates is subjected to centrifugal force and spreads radially while maintaining a concentric shape, so that an adhesive layer having a uniform thickness is formed. Are formed without any gap between the disk substrates. As a result, there is no possibility that the composition cannot be spread only partially and no gap is generated.

The method for manufacturing a disk according to the present invention is also applied to a case where the disk is a DVD.
In the production of DVDs, there is a case where it is required that the uniformity of the adhesive layer between the disk substrates is extremely strict or that the axial acceleration is reduced by minimizing the surface irregularities. By forming an adhesive layer of an ultraviolet-curable composition in this manner, a highly accurate DVD meeting this demand can be manufactured.

The above disk manufacturing method can be implemented by a disk manufacturing apparatus having the following configuration. That is, the disk manufacturing apparatus according to the present invention is a disk manufacturing apparatus in which two disk substrates are bonded to each other as a single disk by bonding a cationic polymerization type ultraviolet curable composition as an adhesive. Coating means for applying the ultraviolet-curable composition to a portion of the bonding surface, ultraviolet-irradiating means for irradiating the applied ultraviolet-curable composition with ultraviolet light, and the ultraviolet-curable composition irradiated with ultraviolet light Laminating means for laminating the one disk substrate and the other disk substrate with a composition therebetween, and a spreading means for spreading the ultraviolet curable composition interposed between both disk substrates. Features.

According to this disk manufacturing apparatus, since the ultraviolet curable composition can be applied from a position closer to the bonding surface, disturbance of the drop trajectory does not occur, and application accuracy can be improved. This prevents the ultraviolet curable composition from protruding between the disk substrates and the generation of gaps.

[0034] In the disk manufacturing apparatus according to the present invention, the coating means includes a discharge section for discharging the ultraviolet curable composition from a fixed position with respect to a bonding surface, and a disk substrate having the bonding surface in a circumferential direction. It is desirable to provide a disk substrate rotation driving unit for rotating the disk substrate at a predetermined speed. When the ultraviolet curable composition is discharged from a fixed position with respect to the bonding surface, and simultaneously rotating one disk substrate having the bonding surface in the circumferential direction, the ultraviolet curable composition forms a concentric circle with the disk substrate. Is applied as follows. When the other disk substrate is bonded thereto and rotated and spread, the ultraviolet-curable composition spreads in the radial direction while maintaining a concentric shape, and an adhesive layer having a uniform thickness is formed without any gap between the disk substrates. You.

In the disk manufacturing apparatus according to the present invention, the ultraviolet irradiating means includes a light source for irradiating the disk substrate coated with the ultraviolet curable composition with ultraviolet light, and an ultraviolet irradiation area irradiated from the light source. And an irradiation region restricting portion for restricting only the ultraviolet curable composition. As described above, the disc substrate may be damaged by the heat from the light source on the information recording layer. Therefore, the irradiation region limiting portion is provided, and the ultraviolet ray is applied only to the ultraviolet curable composition applied to the bonding surface. Irradiates the information recording layer so as not to be affected by the heat from the light source.

[0036] In the disk manufacturing apparatus according to the present invention, the spreading means includes a disk rotation drive unit that holds the two disk substrates bonded together with the ultraviolet curable composition therebetween and rotates the disk substrates in the circumferential direction. It is desirable to have. When the two bonded disc substrates are rotated in the circumferential direction, the ultraviolet-curable composition interposed between the disc substrates is subjected to centrifugal force and spreads radially while maintaining a concentric shape, so that an adhesive layer having a uniform thickness is formed. Are formed without any gap between the disk substrates.

[0037]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment according to the present invention
A description will be given of the manufacture of VD as an example. FIG. 1 shows a schematic configuration of a DVD manufacturing apparatus. In the figure, reference numeral R1 denotes a disk substrate take-out unit, R2 denotes a disk creation unit, R3 denotes a disk inspection unit, and R4 denotes a disk payout unit, all of which are housed inside a case (not shown).

The disk substrate take-out part R1 has a stock area A1 for storing two disk substrates 1a and 1b, which are bonded together to form one disk (DVD), in a state of being separately stacked on the disk holder 2. And a take-out area A2 for taking out the disk substrates 1a and 1b held by each disk holder 2 one by one.

The disk creation unit R2 is provided with a disk substrate 1a
Coating device (coating means) 3 for applying the cationic ultraviolet curable composition toward the bonding surface of the substrate, and an ultraviolet irradiating device (ultraviolet light) for irradiating the disk substrate 1a coated with the cationic ultraviolet curable composition with ultraviolet light. Irradiating means) 4 and disk substrate 1 coated with cationic ultraviolet curable composition
a and the disk substrate 1b are bonded together to form one disk 1
And a spreading device (spreading means) 6 for spreading the disc 1 after bonding.
And an end face processing device 7 for performing an end face hardening process on the spread disc 1 and transferring the end face processed disc 1 from the disc stacking / end face processing stage D to the disc inspection section R3 and the disc discharge section R4. And a transfer device 8 that performs the transfer.

The disk inspection section R3 is constituted by a disk inspection device 9 for inspecting the disk 1 and determining good / bad. The disc dispensing unit R4 includes a good product dispensing unit 10 for dispensing a disc 1 determined to be non-defective and a defective product dispensing unit 11 for dispensing a disc 1 determined to be defective.

Next, a process of manufacturing the disk 1 by the DVD manufacturing apparatus configured as described above will be described. First, one disk substrate 1a stacked on the stock area A1 is supplied to the disk producing unit R2. In the stock area A1, a plurality of disk substrates 1a are stacked on the disk holder 2. When the disk holder 2 is moved from the stock area A1 to the take-out area A2, the disk substrates stacked on the disk holder 2 are moved. The uppermost one of the sheets 1a is moved to the substrate supply position B1 of the coating stage B by a conveying means (not shown).

The disc substrate 1a is turned over by the reversing device 12 when it is transferred to the coating stage B. this is,
In order to prevent foreign matter or the like from adhering to the bonding surface in the previous process, the disk area 1a is provided in the stock area A1.
Is to be stocked with the bonding side down. The same applies to the other disk substrate 1b, which is reversed by the reversing device 12 when transported to the laminating device 5.

The disk substrate 1a transferred to the substrate supply position B1 is moved to the adhesive coating position B2 by rotating the coating stage B in the direction of the arrow in the figure. The coating device 3 applies the cationic ultraviolet curable composition S to the bonding surface of the disk substrate 1a moved to the adhesive application position B2 in a ring shape concentric with the disk substrate 1a. The cationic UV-curable composition S has a light absorption coefficient in the wavelength region of 310 to 340 nm of 2 × 1.
Those having characteristics of 0 ³ m ^-1 or less are used. Such an ultraviolet-curable composition has a photopolymerization initiator of 35%.
It can be obtained by selectively using a material having a relatively small light absorption coefficient of 0 nm or less.

The disk substrate 1a to which the cationic ultraviolet curable composition S has been applied is moved to the substrate transfer position B3 by further rotating the application stage B. The disk substrate 1a moved to the substrate transfer position B3 is temporarily stopped here, and is irradiated with ultraviolet light from the ultraviolet irradiation device 4 toward the cationic ultraviolet curable composition. The disk substrate 1a that has been irradiated with the ultraviolet rays is transported to the bonding apparatus 5 by a transport unit (not shown).

The laminating apparatus 5 has the disk substrate 1 transported from the take-out area A2 by transport means (not shown).
b is on standby after the reversal, and the disk substrates 1a, 1
b is laminated with the bonding surfaces facing each other and bonded together via the cationic ultraviolet curable composition to form one disk 1.

The disk 1 is transported onto the disk stacking / end face processing stage D by a transport means (not shown). In this process, the disk 1 is once transferred to the spreading device 6. Spreading device 6
Then, the disk 1 is gripped using the central hole, rotated at a high speed in the circumferential direction of itself, and spreads the cationic ultraviolet curable composition using centrifugal force. Further, at this time, the axial centers are aligned by aligning the center holes of the disk substrates 1a and 1b.

The disk 1 that has been subjected to the spreading process is transported onto a disk stacking / end surface processing stage D. On the disk stacking / end face processing stage D, disk holders 2 are arranged at equal intervals in the circumferential direction.
First, it is transported onto the disk holder 2 located at the stacking position D1. On the disk holder 2, the disks 1 successively transported by a transport device (not shown) are alternately stacked with the rigid disks G.

A disk holder 2 holding a plurality of disks 1 in a stacked state is a disk stacking / end face processing stage D
Is moved to the curing position D2 with the rotation of. At the curing position D2, a plurality of disks 1 are left stacked on the disk holder 2 for a predetermined period of time to cure the cationic ultraviolet curable composition. The hardening process is performed while the disk 1 moves together with the disk holder 2 along with the rotation of the disk stacking / end face processing stage D, and moves to hardening positions D3, D4, and D5 following the hardening position D2.

The disk 1 after the hardening process is moved to the end surface heating position D5 together with the disk holder 2 with the rotation of the disk stacking / end surface processing stage D. Edge heating position D
In 5, the end surface treatment device 7 heats the cationic ultraviolet curable composition in the vicinity of the end surface to promote curing.

The disk 1 having undergone the end face hardening process is moved to the separation position D6 together with the disk holder 2 as the disk stacking / end face processing stage D rotates. The transfer device 8 includes
There are provided three arms 8a, 8b and 8c which are driven synchronously, and the disk 1 held by the disk holder 2 at the separation position D6 is transported to the disk inspection device 9 by the arm 8b and the inspection is performed at the same time. The disc 1 which has been finished is returned to the non-defective product delivery section 10 or the defective product delivery section 1 by the arm 8c.
It is transported to 1. When the arms 8b and 8c return, the rigid disk G held by the disk holder 2 at the separation position D6 is transported to the stacking position D1 by the arm 8a, and is transported one after another from the laminating device 5. The disk 1 and the disk 1 are alternately stacked. Those determined as defective in the disk inspection device 9 are removed from the regular line, and only those determined as non-defective are stacked on the disk holder 2 prepared in the non-defective product delivery unit 10, and each disk holder 2 It is conveyed to a post process.

As described above, in the disk laminating / end face processing stage D, the disk 1 is alternately laminated with the rigid disk G on the disk holder 2, and the secondary spreading and curing of the ultraviolet curable composition is performed and the holding is performed. The vessel 2 is heated to cure the ultraviolet curable composition at the end face. After spreading of the cationic polymerization type ultraviolet curable composition in this way,
A predetermined curing time is required until the composition is completely cured. During this time, keeping the disk 1 in a flat holding state so as not to apply a strain stress to the disk 1 does not cause distortion or deformation of the disk 1 after curing. Is important.

In consideration of the above, the stage D in the embodiment of the disk manufacturing apparatus can be changed to the following configuration having a flat holding unit and a flat holding device. FIGS. 5, 6, and 7 schematically show a disk manufacturing apparatus having a flat holding device and a flat holding unit. In this apparatus, instead of the disk stacking / end surface processing stage D, a plane holding stage including a plane holding device 20 and a plane holding unit is arranged.

In the disk manufacturing apparatus shown in FIGS. 5 and 6, the disk 1 on which the cationic ultraviolet curable composition has been spread is conveyed to the end face processing device 7, where the disk 1 is removed from both the front and back sides. Light rays including ultraviolet rays and heat rays (infrared rays) are radiated in a flash manner. At this time, irradiation is also performed on the end surface of the disk 1 by using a reflection mirror or the like.
Thereby, the curing of the cationic ultraviolet curable composition near the end face is promoted, and the composition is prevented from protruding from the end face, and is heated by a heat ray, whereby the entire cationic ultraviolet curable composition is heated. Curing time is reduced.

The disk 1 that has undergone the process in the end face processing device 7 is transported to the flat surface holding device 20. Plane holding device 2
0 includes a moving path 21 having a predetermined length and a plane holding unit 80 that moves on the moving path 21 at a predetermined moving speed. As shown in FIG. 7, a flat holding member 87 having through holes 85 and 86 is provided on the upper surface of the flat holding unit 80.
The disk 1 is held in a flat shape on the holding member 87 by performing suction with the fan 84 accommodated inside the flat holding unit 80. Further, the electrode 89 contacts a contact electrode (not shown) provided over the entire length of the moving path 21 to supply a DC voltage to the driving means of the fan 84. The disk 1 is first conveyed onto the plane holding unit 80 located at the starting point (first point) 22 of the moving path 21, and is held flat on the holding member 87 of the plane holding unit 80.

As described above, the plane holding units holding the disk 1 successively sent out onto the movement path of the plane holding apparatus are connected in series, and the plane holding unit 80 is moved along the movement path 21 to the end point (the second point). (Point) 23.
The moving path 21 of the plane holding device 20 is at its highest position 22.
To the lowest position 24 so that the plane holding unit can move continuously. During this time, the disk 1 on the plane holding unit 80 is held flat for a predetermined time, during which the cations The curing of the mold ultraviolet curable composition proceeds, and the shape of the bonded disk 1 is hardened with good flatness without deformation or distortion.

After completing the process in the plane holding device 20, the disk 1 rises from the lowest position 24 to the end point 23, is removed from the plane holding unit 80 at the end point 23, and is conveyed to the disk inspection device 9. You. In the present embodiment, the starting point (first point) 22 and the ending point (second point) 23 of the moving path 21 are the same position.
After the disk 1 is removed from the plane holding unit 80, a new disk 1 is placed on the plane holding unit 80.

In the present embodiment, the transfer device 8 is used as means for transporting the disk 1 from the end face processing device 7 to the flat surface holding device 20 and for transporting the disk 1 from the flat surface holding device 20 to the disk inspection device 9. Is transferred from the disk inspection device 9 to the non-defective product delivery unit 10 by the transfer device 8.
Alternatively, the sheet is conveyed to the defective article dispensing section 11. The transfer device 8 is provided with three arms 8a, 8b, 8c that are driven in synchronization with each other.
When the disc 1 is transported from the disk to the flattening device 20, the arm 8 b simultaneously moves the disk 1 to the flattening device 20.
At the same time as the disk 1 is removed from the flat holding unit 80 that has arrived at the end point 23 and transported to the disk inspection device 9, the inspected disk 1 is removed by the non-defective product delivery unit 10 or the defective product delivery unit by the arm 8 c. 11 is transferred.

The discs judged to be defective in the disc inspection device 9 are removed from the regular line, and only discs judged to be non-defective are stacked on the disc holder 2 prepared in the non-defective product delivery section 10 to hold the disc. The container 2 is transported to the subsequent process.

A coating apparatus 3 for applying the cationic ultraviolet curable composition to the bonding surface of the disk substrate 1a in the DVD manufacturing apparatus generally configured as described above will be described.

As shown in FIG. 2, the coating apparatus 3 discharges the cationic ultraviolet curable composition from a fixed position on the bonding surface of the disk substrate 1a at the adhesive coating position B2 on the coating stage B (see FIG. 2). (Discharge unit) 30 and a disk substrate rotation drive unit 35 that also rotates the disk substrate 1a in the circumferential direction at the adhesive application position B2.

The pump section 30 is provided with a nozzle 31 for discharging a cationic ultraviolet curable composition with its tip directed downward.
The nozzle is fixed at a position where the tip of the nozzle is brought close to the bonding surface of the disk substrate 1a transferred to.

The disk substrate rotation drive unit 35 uses the center hole to grip the disk substrate 1a moved to the adhesive application position B2, and rotates the grip unit 36 together with the disk substrate 1a in the circumferential direction. A driving unit 37 is provided, and is provided integrally with the application stage B.

The manner of operation of the coating device 3 configured as described above will be described. First, the center hole of the disk substrate 1a moved to the adhesive application position B2 is gripped by the gripper. Subsequently, the cationic ultraviolet curable composition is discharged from the tip of the nozzle 31 close to the bonding surface of the disk substrate 1a.

The disk substrate rotation driver 35 rotates the disk substrate 1a in the circumferential direction in synchronization with the discharge of the cationic ultraviolet curable composition from the nozzle 31. At this time, if the temperature of the cationic ultraviolet curable composition satisfies predetermined conditions, the time required for discharging the amount of the cationic ultraviolet curable composition necessary for adhesion from the nozzle 31 is constant. Therefore, the operation of the drive unit 37 is controlled such that the time required for discharging the cationic ultraviolet curable composition takes one time and the disk substrate 1a makes exactly one rotation. As a result, the cationic UV-curable composition is applied to the disk substrate 1
It is applied in a ring shape concentric with a.

As described above, according to the coating apparatus 3, the cationic ultraviolet curable composition can be applied from a position closer to the bonding surface of the disk substrate 1a. The accuracy can be improved.

Next, an ultraviolet irradiation device 4 for irradiating the disk substrate 1a coated with the cationic ultraviolet curable composition with ultraviolet light will be described. The ultraviolet irradiation device 4 is shown in FIG.
As shown in FIG. 5, a light source 40 for irradiating the disk substrate 1a with the cationic ultraviolet curable composition S with ultraviolet light at the substrate transfer position B3 on the coating stage B, and a light source 4
A mask (irradiation region limiting portion) 45 for restricting the irradiation region of the ultraviolet light irradiated from 0 to only the cationic ultraviolet curable composition S is provided.

As the light source 40, a flash-type flash lamp device (SBC13 manufactured by Ushio) is employed, and is disposed immediately above the substrate transfer position B3.

The mask 45 includes the coating stage B and the light source 40.
Are arranged in parallel with the disk substrate 1a moved to the substrate transfer position B3. In the mask 45, the cationic UV-curable composition S on the disk substrate 1a is completely visible when viewed from the UV irradiation direction, and the other substrate surfaces are shadowed so that they cannot be seen through. A ring-shaped opening 46 corresponding to S is formed.

It is desirable that the material of the mask 45 be a material that hardly absorbs light energy such as ultraviolet light, visible light, and infrared light emitted from the lamp and has high light reflectance in a wavelength region covering the entire light beam. When the mask 45 absorbs light energy and the temperature rise becomes large,
This is because heat radiation therefrom may cause thermal deformation of the disk substrate 1a.

The ultraviolet irradiation device 4 configured as described above
The method of operation will be described. The disk substrate 1a to which the cationic ultraviolet curable composition S has been applied is moved to the substrate transfer position B3 as the application stage B rotates. The disk substrate 1a that has been moved to the substrate transfer position B3 is temporarily stopped here, and ultraviolet light is repeatedly and flashly irradiated from the ultraviolet irradiation device 4 toward the cationic ultraviolet curable composition. The input energy to the lamp and the number of times of irradiation per irradiation may be adjusted according to the curing sensitivity of the cationic ultraviolet curable composition used as an adhesive.

As described above, according to the ultraviolet irradiation device 4,
Ultraviolet rays can be applied only to the cationic ultraviolet curable composition S applied to the bonding surface of the disk substrate 1a, so that the information recording layer is not affected by heat from the light source. it can.

Further, since a flash lamp is adopted as the light source 40, the amount of heat retained is smaller than that of the light source of the always-on type, and the cationic ultraviolet light applied to the disk substrate 1a or the bonding surface on the application table B is used. Influence of heat on the curable composition is difficult. In addition, since the power consumption is smaller than that of the light source of the always-on type, the operating cost can be reduced.

Next, a description will be given of the spreading device 6 for spreading the disc 1 after the lamination. The spreading device 6 is shown in FIG.
As shown in the figure, a gripping portion 60 that grips the disk substrates 1a and 1b, that is, the disk 1, which is bonded to each other with the cationic ultraviolet curable composition S interposed therebetween, using a center hole, and the gripping portion 60 with the disk 1 in the circumferential direction. Driving unit 61 that rotates
And

The manner of operation of the spreading device 6 configured as described above will be described. The disc 1 transferred to the spreading device 6 has its center hole gripped by the gripper 60, and is given a rotational motion in the circumferential direction by the drive unit 61. When the disk 1 rotates in the circumferential direction, the cationic ultraviolet curable composition S interposed between the disk substrates 1a and 1b receives centrifugal force and spreads in the radial direction while maintaining a concentric shape, whereby an adhesive layer having a uniform thickness is formed. It is formed without any gap between the disk substrates 1a and 1b.

As described above, according to the spreading device 6, the cationic ultraviolet curable composition S spreads in the radial direction while maintaining the concentric shape, and the adhesive layer having a uniform thickness is formed on the disk substrate 1.
Since there is no gap in the entire space between a and 1b, the cationic ultraviolet curable composition S does not spread and no gap is generated.

By the way, in the present embodiment, the spinning type utilizing the centrifugal force is adopted as the spreading device 6,
Instead, a spreading device of a type in which the disc 1 is pressed from both sides may be adopted.

Next, a second embodiment according to the present invention will be described with reference to FIG. In the present embodiment, a tubular member 101 and a plate-like member 102 are given as examples of members to be bonded.
A method of bonding the plate-like member 102 to the opening will be described. FIG. 8 shows the bonding method of the present embodiment in the order of steps.

In the present embodiment, the tubular member 101 is a square tubular member, and the plate member 102 is a rectangle that seals the opening of the tubular member 101. However, in FIG. Only a part of 102 is shown. As shown in FIG. 8A, a concave groove 101b is formed on the entire open end face of the cylindrical member 101, and the concave groove 1b is formed.
01b is an inner bank 101a.
c. On the other hand, as shown in FIG. 8D, the plate-like member 102 is formed in a shape to be fitted into a bank 101c outside the tubular member 101.

First, as shown in FIG.
The ultraviolet curable composition 103 is applied in 1b. As the ultraviolet curable composition 103, the wavelength region 310 to 340
A material having a light absorption coefficient in nm of 2 × 10 ³ m ⁻¹ or less is used. Such an ultraviolet curable composition can be obtained by selectively using a material having a relatively small light absorption coefficient of 350 nm or less as a photopolymerization initiator. The application amount of the ultraviolet-curable composition 103 is set to be slightly larger than the volume of the space in the concave groove 101b so that a part of the ultraviolet-curable composition 103 protrudes on the inner bank portion 101a in a later spreading step. To

Next, as shown in FIG.
The ultraviolet curable composition 103 applied in b is irradiated with ultraviolet light. UV irradiation is not shown,
The masking is performed right above the opening end face of the cylindrical member 101, and a mask that limits the irradiation region of the ultraviolet rays only to the ultraviolet curable composition 103 is used. The irradiation amount of the ultraviolet rays may be adjusted according to the curing sensitivity of the ultraviolet-curable composition 103 used as the adhesive. By using a mask at the time of irradiating the ultraviolet rays, the ultraviolet rays can be radiated only to the ultraviolet curable composition 103 applied in the concave groove 101b, so that the tubular member 101 itself emits heat from the light source. Can be unaffected.

After the ultraviolet irradiation, as shown in FIG.
The plate member 102 is fitted into the opening of the cylindrical member 101,
Further, the plate-shaped member 102 is pressed in a direction in which the plate-shaped member 102 is pressed against the inner bank 101a of the cylindrical member 101, and a part of the ultraviolet-curable composition 103 is spread on the inner bank 101a. Thereby, the cylindrical member 101 and the plate-shaped member 102 are bonded via the ultraviolet curable composition 103 in the concave groove 101b and the ultraviolet curable composition on the inner bank 101a.

The tubular member 101 thus bonded is
In addition to the ultraviolet curable composition 103 applied in the concave groove 101b over the entire periphery of the opening of the cylindrical member 101, the inner wall 101
Since the ultraviolet-curable composition 103 spread on a is also interposed, the adhesive area between the two members is large and the adhesive strength is strong. Further, the adhesive layer made of the ultraviolet curable composition 103 is formed without a gap over the entire circumference of the opening of the cylindrical member 101, and the bonding area of the adhesive layer is large. The effect of sealing the opening of the member 101 is also high.

Further, by applying the ultraviolet curable composition 103 and irradiating it with ultraviolet light, the two members are fitted to each other, whereby the bonding can be performed in a short time. For example, without using an ultraviolet curable composition, in a method using a thermosetting adhesive, aging for several hours is required at the time of bonding, but according to the method of the present embodiment, the time required for bonding is extremely short. And thus can be applied to a continuous process to improve productivity.

In this embodiment, the example in which the plate member 102 is bonded to the opening of the cylindrical member 101 has been described. However, the shape of the member and the portion to be bonded can be changed as appropriate. Can be applied to bonding of various members. In the present embodiment, the tubular member 101 which is the portion to be bonded is
A groove 101b was provided on the opening end face of the substrate, and the ultraviolet-curable composition 103 was applied in the groove 101b. However, no groove was formed in the portion to be bonded, and the ultraviolet-curable composition was linearly formed on a flat surface. It may be applied. In this case, if the member to be bonded is pressed in combination with the site to which the ultraviolet-curable composition has been applied, the ultraviolet-curable composition spreads over its application area. The members are adhered, and a strong adhesive force and excellent sealing properties are obtained.

Further, in the present embodiment, an ultraviolet curable composition having a light absorption coefficient of 2 × 10 ³ m ⁻¹ or less in a wavelength region of 310 to 340 nm was used. It is only necessary to have physical properties that can be spread to a required spread area by an appropriate spreading method after irradiation with ultraviolet rays, and depending on the shape and size of a portion to be bonded, a required bonding state, and the like, other than the above. The ultraviolet curable composition of the above can also be used.

Finally, the adhesive which can be used in the present invention will be described. As the cationic UV-curable composition as an adhesive usable in the present invention, a composition suitable for carrying out the present invention can be selected from known and commonly used compositions, or a combination thereof can be used. An epoxy resin containing a photopolymerization initiator of the type corresponds to this. Examples of the cationic polymerization type photopolymerization initiator include a sulfonium salt, an iodonium salt and a diazonium salt.

As the adhesive of the present invention, a cationically polymerizable UV-curable composition containing a cationic photopolymerization initiator and a glycidyl ether type epoxy resin can be used, and the light of the composition in a wavelength region of 310 to 340 nm can be used. The absorption coefficient of 2 × 10 ³ m -1 or less can be achieved by selecting a cationic photopolymerization initiator having a small light absorption coefficient particularly in a wavelength region of 310 to 340 nm. Initiators which may satisfy the conditions include those wherein the cation moiety is an aromatic sulfonium such as diphenyl-4- (phenylthio) phenylsulfonium, triphenylsulfonium, diphenyliodonium, bis (dodecylphenyl) iodonium, 4-methyl An aromatic iodonium such as phenyl-4- (1-methylethyl) phenyliodonium, wherein the anion portion is BF ₄ ⁻ , PF ₆ ⁻ , SbF ₆ ⁻ , [BX ₄ ] ⁻ (where,
X is an onium salt composed of at least two or more phenyl groups substituted by fluorine or a trifluoromethyl group. As an initiator that can be used in combination with these initiators, the cation portion is an aromatic sulfonium such as bis [4- (diphenylsulfonio) phenyl] sulfide, and the anion portion is BF ₄ ⁻ , PF ₆ ⁻ , Sb
Onium salts composed of F ₆ ⁻ , [BX ₄ ] ⁻ (where X is a phenyl group substituted by at least two or more fluorines or trifluoromethyl groups), but the absorption coefficient is not small, Even if it is used, it is preferable to make the usage amount as small as possible.

Further, in order to suppress the partial curing of only the surface, it is preferable to contain an aliphatic polyol polyglycidyl ether as the glycidyl ether type epoxy resin. Due to the aliphatic polyol polyglycidyl ether, polymerization of the composition occurs after light irradiation,
Hardening of the surface can be suppressed.

As the aliphatic polyol polyglycidyl ether, for example, ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether,
Neopentyl glycol diglycidyl ether, butanediol diglycidyl ether, hexanediol diglycidyl ether, cyclohexane dimethanol diglycidyl ether, polypropylene glycol diglycidyl ether, trimethylolpropane di and / or triglycidyl ether, pentaerythritol tri and / or
Or tetraglycidyl ether, sorbitol hepta and / or hexaglycidyl ether.

[0090]

As described above, according to the present invention,
Since the ultraviolet-curable composition can be applied from a position closer to the portion to be bonded, disturbance of the drop trajectory does not occur, and application accuracy can be improved. Thereby, it is possible to prevent the ultraviolet curable composition from protruding between the members to be bonded and the occurrence of gaps.

Further, the ultraviolet curable composition applied to the member to be bonded is irradiated with ultraviolet rays, and then the ultraviolet curable composition is spread, so that the bonding area between the two members to be bonded is increased, and strong bonding is achieved. A force is obtained and a high sealing effect is obtained.

Furthermore, by bonding one member to be bonded and the other member to be bonded via the ultraviolet curable composition after the ultraviolet irradiation, both members can be bonded in a short time. Therefore, the time required for the bonding step is extremely short as compared with the hot-melt type adhesive, so that it can be applied to a continuous step and can contribute to an improvement in productivity.

Further, by using an ultraviolet curable composition having a light absorption coefficient of 2 × 10 ³ m ⁻¹ or less in a wavelength region of 310 to 340 nm, ultraviolet rays can be sufficiently transmitted to the inside and between the surface and the inside. Since the difference in the state of curing hardly occurs, the ultraviolet-curable composition spreads uniformly during spreading.
Thereby, the adhesive layer is uniformly formed between the members to be bonded,
It is possible to prevent the ultraviolet curable composition from protruding or generating a gap between the members to be bonded.

[Brief description of the drawings]

FIG. 1 is a view showing a first embodiment of the present invention, and is a plan view showing a schematic configuration of an optical disk manufacturing apparatus.

FIG. 2 is a side view showing a schematic configuration of a coating apparatus.

FIG. 3 is a side view showing a schematic configuration of an ultraviolet irradiation device.

FIG. 4 is a side view showing a schematic configuration of the spreading device.

FIG. 5 is a plan view showing a schematic configuration of an optical disk manufacturing apparatus having a plane holding stage.

FIG. 6 is a side view showing a schematic configuration of the flat surface holding device.

7A and 7B show a flat holding unit, wherein FIG. 7A is a plan view and FIG. 7B is a side view.

FIG. 8 is a view showing a second embodiment according to the present invention in the order of steps.

[Explanation of symbols]

 1a, 1b disk substrate 1 disk 2 disk holder 20 plane holding device (plane holding device) 21 moving path 3 coating device (coating device) 30 pump (discharge unit) 35 disk substrate rotation drive unit 4 ultraviolet irradiation device (ultraviolet irradiation Means) 40 Light source 45 Mask (irradiation area limiting unit) 5 Laminating device (laminating device) 6 Spreading device (spreading device) 60 Gripping unit 61 Drive unit 80 Flat holding unit 84 Fan 85 First through hole 86 First 2 through-hole 87 holding member 89 electrode 101 cylindrical member (member to be bonded) 102 plate member (member to be bonded) 103 ultraviolet curable composition

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Daisuke Ito 4-12-8-205 Midorioka, Ageo-shi, Saitama F-term (reference) 4J040 PA07 PA32 PA33 PB06 PB08 5D121 AA07 FF03 FF13 FF18 GG02 GG28 JJ07

Claims (13)

[Claims] 1. A method of bonding two members to be bonded via an ultraviolet-curable composition, wherein the ultraviolet-curable composition is applied to a part of a bonded portion of one of the members to be bonded. A step of irradiating the applied ultraviolet-curable composition with ultraviolet light, and bonding the one member to be bonded and the other member to be bonded via the ultraviolet-curable composition irradiated with ultraviolet light. And a step of spreading the ultraviolet-curable composition interposed between both members to be bonded, and the ultraviolet-curable composition is a cationic polymerization-type ultraviolet-curable composition. The method of bonding the members. 2. The composition according to claim 1, wherein the cationically curable ultraviolet-curable composition comprises:
The light absorption coefficient in the wavelength region of 310 to 340 nm is 2 ×
The method for bonding members according to claim 1, wherein the thickness is 10 ³ m ^-1 or less. 3. The method according to claim 1, wherein only the ultraviolet curable composition applied to the portion to be bonded is irradiated with ultraviolet light.
Or the method for bonding members according to 2. 4. A method of manufacturing a disk by bonding two disk substrates to one another by bonding a cationic polymerization type ultraviolet curable composition as an adhesive, wherein one of the disk substrates has a part of a bonding surface. Applying the UV-curable composition to the UV-curable composition, irradiating the applied UV-curable composition with ultraviolet light, and sandwiching the ultraviolet-curable composition irradiated with ultraviolet light, the one disk substrate. A method for manufacturing a disk, comprising: a step of bonding the other and the other disk substrate; and a step of spreading the ultraviolet curable composition interposed between the two disk substrates. 5. The method according to claim 1, wherein the ultraviolet curable composition has a wavelength region of 31.
5. The method according to claim 4, wherein the composition is a cationic polymerization type ultraviolet curable composition having a light absorption coefficient at 0 to 340 nm of 2 × 10 ³ m ⁻¹ or less. . 6. The disk manufacturing method according to claim 4, wherein the ultraviolet curable composition is applied to the disk substrate so as to form a concentric circle. 7. The disk manufacturing method according to claim 4, wherein only the ultraviolet curable composition applied to the bonding surface is irradiated with ultraviolet rays. 8. The disk according to claim 4, wherein at the time of spreading, the two disk substrates bonded together with the ultraviolet curable composition therebetween are rotated in a circumferential direction. Production method. 9. The method according to claim 4, wherein the disk is a DVD. 10. A disk manufacturing apparatus in which two disk substrates are bonded to each other as a single disk by bonding a cationic polymerization type ultraviolet curable composition as an adhesive, and a part of a bonding surface of one disk substrate is provided. Coating means for applying the ultraviolet-curable composition to the ultraviolet-ray-curable composition; ultraviolet-ray irradiating means for irradiating the applied ultraviolet-curable composition with ultraviolet light; A disc manufacturing apparatus, comprising: a laminating unit for laminating the disc substrate and the other disc substrate; and a spreading unit for spreading the ultraviolet curable composition interposed between the two disc substrates. 11. A discharge unit that discharges the ultraviolet-curable composition from a fixed position with respect to a bonding surface,
The disk manufacturing apparatus according to claim 10, further comprising a disk substrate rotation drive unit that rotates the disk substrate having the bonding surface in a circumferential direction. 12. The ultraviolet light irradiating means includes: a light source that irradiates the disk substrate coated with the ultraviolet curable composition with ultraviolet light; and an ultraviolet irradiation area irradiated from the light source to the ultraviolet curable composition. 12. An irradiation area restricting unit for restricting only an irradiation area.
The disk manufacturing apparatus according to the above. 13. The apparatus according to claim 1, wherein the spreading means includes a disk rotation drive unit that grips two disk substrates bonded together with the ultraviolet curable composition therebetween and rotates the disk substrates in a circumferential direction. 13. The disk manufacturing apparatus according to any one of 10 to 12.