JP2003211057A - Coating method and coater for liquid-like object, and lamination method and lamination apparatus for disk- like object - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To make the coating quantity of a liquid-like object to a disk-like object uniform over the entire part. <P>SOLUTION: A central hole CH of a disk substrate 1a is clamped by a clamping section 31, and in this state, the disk substrate is rotated by a driving section 32. A pump 29 is installed above the disk substrate 1a and a cation polymerization type UV curing resin composition is applied as an adhesive S from a nozzle section 29a to the disk substrate. The rotating speed of the disk substrate is controlled in order of a rising part where the speed increases gradually, a constant speed part where the constant speed is maintained and a falling part where the speed is gradually lowered. Discharge control means 35 which detects the rotating speed of the disk substrate 1a and performs control to discharge the adhesive from the nozzle section 29a in the state that the constant speed is attained is disposed. The adhesive of a fixed amount is continuously discharged from the nozzle section 29a to the disk substrate 1a rotating at the constant speed, by which the adhesive S is applied to in a concentric circular form with the central hole and an annular coating application region of uniform coating quantity and uniform coating width is formed over the entire circumference of the disk substrate 1a. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating method and a coating apparatus for uniformly coating a liquid object in a ring shape or the like. Further, the present invention relates to a laminating method and a laminating apparatus having a step of applying an adhesive to a disc-shaped object using these methods and apparatuses, and particularly, for example, a digital video / versatile disc (hereinafter, abbreviated as DVD). The present invention relates to a bonding method and a bonding device for a disc-shaped object such as a disk substrate which is suitable for use in manufacturing an optical disk or the like.

[0002]

2. Description of the Related Art Conventionally, when manufacturing a digital video / versatile disk, a so-called DVD, a method has been adopted in which two disk substrates are bonded by using an ultraviolet curable resin composition or the like as an adhesive. The ultraviolet curable resin composition here includes at least a cationic polymerization type ultraviolet curable resin composition and a radical polymerization type ultraviolet curable resin composition. Of these, when the radical-polymerizable ultraviolet-curable resin composition is used as an adhesive, the radical-polymerizable ultraviolet-curable resin composition is applied to one disk substrate in an annular shape because the curing speed by ultraviolet irradiation is high. Then, the other disk substrate is adhered, and the radical-polymerization type ultraviolet curable resin composition is spread between both disk substrates, and then it is cured by being irradiated with UV through the disk substrate to be cured and bonded to one sheet. You will get a disc. The cation-polymerizable UV-curable resin composition is an adhesive that has the property of gradually hardening after UV irradiation and hardening after a predetermined time elapses, and is therefore suitable for laminating disk substrates that do not transmit UV light. Can be used. In order to manufacture a disc using the cationic polymerization type ultraviolet curable resin composition, the cationic polymerization type ultraviolet curable resin composition is applied to the surface of one of the disc substrates in a substantially annular shape. The composition is exposed to ultraviolet light. Then, the other disk substrate is laminated and bonded, and both disk substrates are rotated (spun) to spread the cationic polymerization type ultraviolet curable resin composition between both substrates. Then, the two cationically polymerizable UV-curable resin compositions are cured to bond the two disk substrates to each other.
A disc is completed.

By the way, the cationic polymerization type UV-curable resin composition applied in an annular shape on the disk substrate in the coating step is spread by centrifugal force generated by rotating two disk substrates in the spreading step. Will be scattered to the outside. In this case, the cationic polymerization type ultraviolet curable resin composition has already been irradiated with UV and thus has been cured, and cannot be recovered and reused. In order to prevent such waste, it is necessary to minimize the coating amount of the cationic polymerization type UV curable resin composition. Further, if there is unevenness in the coating amount in the circumferential direction of the cationic polymerization type UV-curable resin composition applied in a ring shape, there is a possibility that wasteful scattering to the outside will occur partially, and in the portion where the coating amount is small. There is a risk of defective joints and air bubbles due to insufficient spreading. Therefore, when the cationic polymerization type ultraviolet curable resin composition is applied in an annular shape, it is necessary to make the applied amount and the applied width uniform throughout so that the applied cross sectional area is as uniform as possible.

Therefore, for example, the Japanese Patent Application No. 20 which is a prior art.
In the application No. 01-152910, when a plunger pump or a capacity-measuring pump is used as a coating means of the cationic polymerization type UV-curable resin composition, residual pressure remains at the discharge port and liquid is accumulated at the tip, resulting in uneven coating amount. In order to cause the above, a technique has been proposed in which a two-stage valve pump is adopted to prevent the liquid pool remaining at the tip of the discharge port. The two-stage valve pump has a drawback that the discharge amount changes due to the change in the liquid viscosity caused by the change in the liquid temperature, but the liquid temperature change is ± 0.1%.
The discharge amount is stabilized by controlling at ℃.

[0005]

However, even if a fixed amount is continuously discharged using the above-mentioned means for applying the cationically polymerizable ultraviolet-curable resin composition, for example, as shown in FIG.
As shown in (a), when the adhesive is discharged in the entire area including the rising and falling of the rotational movement of the disk substrate in the coating process, the rising and falling can be dealt with as shown in FIG. The application amount at the start and end of the ejection becomes larger than that at the constant speed rotation, and the application amount and the application width in the annular application region Sb partially increase at the connecting portions S1 at both ends. When two disk substrates are stacked in this state and rotated to spread the cationic polymerization type ultraviolet curable resin composition, the cationic polymerization type ultraviolet curable resin composition is scattered from the outer peripheral edge of the disk substrate. When the rotation of the disc substrate is stopped by detecting the above, the rotation of the disc substrate is stopped when the cationically polymerized UV-curable resin composition of the connecting portion S1 is first scattered. Therefore, the cationically polymerizable ultraviolet-curable resin composition in other regions does not spread sufficiently to the outside, or spreads too much to the inside of the connecting portion S1 and sticks out from the inner peripheral edge, or the application region other than the connecting portion S1. Problems such as insufficient inner spreading of Sb occur. As described above, unless the coating amount and the coating width in the circumferential direction of the annular cationic polymerization type ultraviolet curable resin composition are sufficiently uniform, the above-mentioned problems during the spreading treatment cannot be sufficiently improved. In view of such circumstances, it is an object of the present invention to provide a liquid object coating method and a coating apparatus capable of uniformly coating the liquid object onto the object to be coated. Another object of the present invention is to provide a bonding method and a bonding device for disk-shaped objects, which can make the amount of adhesive applied to the disk-shaped objects uniform throughout.

[0006]

A coating method according to the present invention is a coating method in which a liquid object is coated in an annular shape on an object to be coated, and the relative rotation speed between the discharge port of the liquid object and the object to be coated is It is characterized in that the liquid object is applied in a substantially constant state. Even if the coating amount of the liquid object is almost uniform, the relative rotation speed between the discharge port and the object to be coated changes. Although the coating amount per length will change, in the present invention, since the coating of the liquid object from the discharge port is started in the state where the relative rotation speed is constant and the coating is finished in the state of constant speed, The application amount and application width of the object are uniform over the entire annular application region. Therefore, highly accurate coating can be performed, and by spreading this, a liquid object having a uniform thickness can be obtained over the entire surface.

The coating method according to the present invention is a coating method in which a liquid object is linearly continuous with an object to be coated and both ends are connected, and the discharge amount of the liquid object from a discharge port is substantially uniform. Therefore, it is characterized in that the liquid object is applied in a state where the relative speed of the discharge port of the liquid object and the object to be coated is substantially constant. In the present invention, the application of the liquid object is started because the application of the liquid object from the ejection port is started in a state where the relative speed between the ejection port of the liquid object and the object to be coated is constant and the application is finished in the constant speed state. The amount and coating width are uniform over the entire coating area.

The disc-shaped object laminating method according to the present invention is a laminating method in which two disc-shaped objects are pasted with an adhesive sandwiched between them, and the ejection port of the adhesive and the disc-shaped object are bonded together. And a relative rotation to apply an adhesive in an annular shape to the inner peripheral portion of at least one of the two disk-shaped objects, and two disk-shaped objects sandwiching the adhesive. And a spreading step of spreading the adhesive by rotating after bonding, and in the coating step, the relative rotation speed between the discharge port of the adhesive and the disk-shaped object is substantially constant. It is characterized in that the adhesive is applied to the disk-shaped object. In the present invention, since the application of the adhesive from the ejection port is started in a state where the relative rotation speed between the ejection port of the adhesive and the disk-shaped object is constant and the application is finished in the constant speed state, the adhesive The coating amount and the coating width are uniform over the entire annular coating area. When two disk-shaped objects bonded with an adhesive sandwiched between them are rotated and spread, the adhesive will be spread evenly outside and also inside by the centrifugal force over the entire circumference. If a part of the adhesive is scattered outside the disk-shaped object and the spreading is detected and the spreading is completed, the adhesive will not be insufficiently spread to the outside and will be spread to the inside without excess or deficiency. Postpone.

The adhesive may be a cationic polymerization type ultraviolet curable resin composition. In particular, when laminating a disc-shaped object that does not transmit ultraviolet rays using this composition, this composition is already irradiated with ultraviolet rays at the time of spreading and is scattered and consumed from the end of the disc-shaped object. Reuse is therefore impossible. However, according to the method of the present invention, the amount of the above composition is wasted due to scattering in an unrecoverable state because the spreading is performed uniformly in the circumferential direction and a partial excess of the adhesive does not occur. Can be extremely reduced.
The disk-shaped object is a disk substrate, and two disk substrates may be bonded together to form a disk. A disc with high bonding strength can be manufactured.

A coating device for a liquid object according to the present invention is a coating device for coating a liquid object on an object to be coated in an annular shape,
A discharge port for discharging a liquid object, a relative rotation means for relatively rotating the discharge port and an object to be coated, and a liquid object to be discharged from the discharge port in a state where the relative rotational speed of the discharge port and the object to be coated is substantially constant. And a discharge control means. In the present invention, since the liquid object is applied from the ejection port in a state where the relative rotation speed between the ejection port of the liquid object and the object to be coated is constant, the application amount and the application width of the liquid object are annular coating areas. It becomes uniform throughout. Further, spreading means may be further provided which spreads the liquid object by rotating the two disk-shaped objects which are the objects to be coated with the liquid object sandwiched therebetween. By rotating and spreading the two disk-shaped objects that have been stuck together, a liquid object applied in an annular shape between the disk-shaped objects can be uniformly spread outside and inside over the entire circumference. it can.

A disc-shaped object laminating apparatus according to the present invention is a laminating apparatus for laminating two disc-shaped objects by using a cationic polymerization type ultraviolet curable resin composition as an adhesive. A discharge port for discharging, a relative rotation means for relatively rotating the discharge port and the disk-shaped object, and a discharge for discharging the adhesive from the discharge port in a state where the relative rotational speed of the discharge port and the disk-shaped object is substantially constant. A control unit, an ultraviolet irradiation unit that irradiates the adhesive with ultraviolet rays in a state where the adhesive is applied to the disk-shaped object, and an adhesive that is irradiated with ultraviolet rays are sandwiched between the control unit and the ultraviolet irradiation unit.
It is characterized in that it is provided with a bonding means for bonding the disc-shaped objects and a spreading means for spreading the adhesive agent interposed between the two disc-shaped objects. Since the adhesive is applied from the ejection port in a state where the relative rotation speed between the ejection port of the adhesive and the disk-shaped object is constant, the application amount and the application width of the adhesive are in the annular application area. When the two disc-shaped objects that are bonded together with the adhesive sandwiched are spread,
Since the adhesive spreads outward uniformly over the entire circumference due to centrifugal force, the adhesive does not spread insufficiently to the outside, and also spreads to the inside without excess or deficiency. The disk-shaped object is a disk substrate, and two disk substrates may be bonded together to form a disk.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION DVD according to an embodiment of the present invention
The manufacturing apparatus will be described. FIG. 1 shows a schematic configuration of a DVD manufacturing apparatus. In the figure, reference numerals R1 and R2 are both disc substrate ejecting portions, R3 is a disc producing portion, R4 is a disc inspecting portion, and R5 is a disc ejecting portion, both of which are housed inside a case (not shown). The disc substrate take-out portion R1 is attached to one disc (DV
A stock device 3 for stocking a plurality of layers of one of the two disk substrates (plate-like objects) forming D) in the disk holder 2 and a disk substrate 1a held by the disk holder 2 It is composed of a take-out device 4 for taking out the sheets one by one. Similarly, the disk substrate take-out section R2
A stock device 3 for stocking the other of the two disk substrates in a plurality of layers and a stocked disk substrate 1b
It is configured separately from the take-out device 4 for taking out the sheets one by one.

The disk producing section R3 is provided with a disk substrate 1a.
A coating device 5 (coating means) for coating, for example, an annular shape with the ultraviolet curable resin composition (in this case, a cationic polymerization type ultraviolet curable resin composition) as the adhesive S on the overlapping surfaces of
And an ultraviolet irradiator 6 (ultraviolet irradiating means) for irradiating the disk substrate 1a coated with the adhesive S with ultraviolet rays, and the disk substrate 1b is superposed on the disk substrate 1a with the coated adhesive S therebetween. The laminating device 7 (laminating means) for forming the disk 1 and the spreading device 8 (spreading means) for rotating and spreading the stacked disk substrates 1a and 1b in the circumferential direction, and the spreading is completed. An end surface processing device 9 for flashing light including ultraviolet rays and infrared rays onto the disk 1 to perform end surface hardening processing, and a flat surface holding device for hardening the disk 1 after the end surface processing for a predetermined time while holding the disk 1 in a planar shape. 10 and 10. The spreading device 8 is provided with two systems (8A, 8B), but this requires a longer time for the spreading process than the bonding of the disk substrates 1a and 1b, and thus continuous disk manufacturing production. The two spreading devices 8A,
By alternately transferring the disk 1 to the 8B and expanding the disk 1, the time required for the expansion can be substantially halved. The flat surface holding device 10 includes, for example, triple circuit circuits 11, 12, 13
And a plurality of lifting devices 14, 15 and 16 for lifting and lowering between the respective peripheral circuits 11, 12 and 13 on the third floor, and a plurality of flat holding units 1 for holding the bonded disks 1.
It is possible to complete the curing while preventing the deterioration of the warp by sequentially mounting the peripheral circuits 11, 12 and 13 on the vehicle 8 in sequence.

The disk inspection unit R4 is composed of a disk inspection device 19 which inspects the disk 1 to determine whether it is good or bad. The disc payout unit R5 includes a non-defective product payout unit 20 that pays out the disc 1 that is determined as a non-defective product, and a defective product payout unit 21 that pays out the disc 1 that is determined as a defective product.

By the way, the coating apparatus 5 according to the present embodiment
Has the configuration shown in FIGS. 2 and 3. That is, FIG.
In the coating device 5, the rotation driving unit 28 (relative rotation means) of the disc substrate 1a provided on the coating stage 30 and the cationic polymerization type ultraviolet curable resin composition which is a liquid substance as an adhesive are provided at predetermined positions of the disc substrate 1a. A pump 29 for applying in an annular shape is provided. The coating table 30 has a mounting surface 30a for mounting one of the disk substrates 1a. The rotation driving unit 28 of the disk substrate 1a is integrally provided on the coating table 30, and the gripping unit 31 and the gripping unit that can be retracted into and from the central hole CH of the disk substrate 1a and the hole 27 provided on the mounting surface 30a. The drive unit 32 includes a drive unit 32 that supports the drive unit 31 so as to be retractable, and that can rotate the grip unit 31 together with the disk substrate 1a around the central axis O. The hole 27 has an inner diameter equal to or larger than that of the central hole CH. In the grip portion 31, a plurality of, for example, three grip pins 33 are arranged along a circular ring substantially coaxial with the central axis O at predetermined angles (for example, at intervals of 120 °), and each grip pin 33 is formed by an elastic member (not shown). It is urged radially inward, that is, in the direction of the central axis O. Each grip pin 33 has a substantially rod shape, and extends substantially parallel to the central axis O, and has an upper end formed as a claw portion 33a that is bent or curved outward. Claw 33a
Prevents the disc substrate 1a from floating during rotation, and positions the disc substrate 1a in the vertical direction. The drive part 32 moves the grip part 31 back and forth in the longitudinal direction thereof to move the central hole CH of the disk substrate 1a.
And the mounting surface 30a, and each gripping pin 33a is radially expanded outward against the biasing force of the elastic member to grip the disk substrate 1a at the inner peripheral edge of the central hole CH, thereby discping the disk substrate. 1a will be rotated.

The pump 29 constitutes a discharge means and is provided on the disk substrate 1a on the opposite side of the coating stage 30, that is, on the upper side. The nozzle portion 29a extends downward and the tip 29b (discharge port) is a disk. It is in a fixed position close to the substrate 1a and radially displaced from the central axis O of the drive unit 32 by a predetermined distance. Therefore, the adhesive agent S discharged from the nozzle portion 29a rotates around the central axis O and the disk substrate 1
It is applied to the clamp area of a in an annular shape concentric with the central hole CH. Also, this pump 29 is, for example, 2
It is composed of a multi-stage valve pump and can prevent the liquid pool remaining at the tip of the discharge port. Moreover, the temperature variation of the adhesive in the pump 29 is controlled within ± 0.1 ° C. to stabilize the discharge amount. Therefore, the discharge amount of the adhesive S discharged from the nozzle portion 29a of the pump 29 per unit time becomes substantially uniform. Further, the pump 29 is electrically connected to the discharge control means 35, and the drive section 32 is connected to the grip section 3.
1, i.e., the rotation speed detecting means 36 for detecting the rotation speed of the disk substrate 1 a, and the rotation speed detecting means 36 is electrically connected to the ejection control means 35. Then, in the discharge control means 35, the rotation speed detection means 3
When the rotation speed of the grip portion 31, that is, the disk substrate 1a detected in 6 is a constant speed, the nozzle portion 29a of the pump 29 is
The adhesive is controlled to be ejected from the disk substrate 1a.
The adhesive is controlled so as not to be ejected at the rising of the rotation speed of or at the falling of the rotation speed.

Next, a method of manufacturing the disc 1 by the DVD manufacturing apparatus configured as described above will be described. First, in the disc substrate unloading section R1 shown in FIG. 1, the stock stage A constituting the stock device 3 rotates in the direction of the arrow in the figure, and one of the plurality of disc holders 2 installed on the stage moves to the substrate unloading position A1. To prepare for substrate extraction by the extraction device 4. On each disc holder 2, disc substrates 1a and spacers (not shown) are alternately laminated. The take-out device 4 is driven in synchronization with 2
The disc substrate 1a is provided with book arms 4a and 4b and is held by the disc holder 2 at the substrate take-out position A1.
The uppermost one of them is transported to the substrate receiving position B1 on the coating stage B by the arm 4a. Further, during the return operation of the arm 4a, the spacer held by the disk holder 2 at the substrate take-out position A1 is conveyed by the arm 4b to the spacer collector 51 and collected. Similarly, in the disc substrate take-out section R2, the stock stage A constituting the stock device 3 rotates in the direction of the arrow in the figure, and one of the plurality of disc holders 2 installed on the stage moves to the substrate take-out position A1. . Then, the board take-out position A1
The uppermost one of the disc substrates 1b held by the disc holder 2 is transferred to the stacking device 7 by the arm 4a and transferred to the reversing arm 52. Further, during the return operation of the arm 4a, the spacer held by the disk holder 2 at the substrate take-out position A1 is conveyed to the spacer collector 53 by the arm 4b and collected.

The disk substrate 1a transported to the substrate receiving position B1 moves to the adhesive coating position B2 as the coating stage B rotates in the direction of the arrow in the figure. Adhesive application position B
On the superposed surface of the disk substrate 1a which has been moved to the position 2, the adhesive S has a ring which is concentric with the central hole CH in the clamp area located inside the surface of the disk substrate 1a on which the information recording layer is provided by the coating device 5. It is applied in a linear manner so as to draw. It is desirable that the application amount here is as uniform and quantitative as possible in the circumferential direction, and that only the necessary amount is applied. One of the reasons for this is to minimize the amount of the adhesive S that is scattered to the outside of the disk 1 during rotational spreading. The second reason is that if the line width of the ring-shaped coating material after coating becomes wide, the adhesive agent S will squeeze out from the central hole CH to the inner peripheral side before it is transferred to the rotary spreading step, which causes a defective finish. This is to prevent As the adhesive S, a cationic polymerization type UV curable resin composition having a light absorption coefficient of 2 × 10 ³ m ⁻¹ or less in the wavelength region of 310 to 340 nm is used. Such an adhesive S is obtained by selectively using a material having a relatively small light absorption coefficient of 350 nm or less as a photopolymerization initiator.

A method of applying the adhesive S will be described in detail with reference to FIGS. First, in FIG.
When the disc substrate 1a is placed at a predetermined position on the mounting surface 30a of the coating stage 30 and is rotated to the adhesive coating position B2, the grip 31 submerged in the hole 27 of the coating stage 30 becomes the disc substrate. It penetrates the central hole CH of 1a and projects upward. Next, the driving unit 32 causes the plurality of gripping pins 33 of the gripping unit 31 to radially expand outward against the biasing force of the elastic member, whereby the disc substrate 1 a is gripped by the gripping unit 31. In this state, the disk substrate 1a becomes coaxial with the central axis O which is the center of rotation of the drive unit 32. Then, by driving the driving unit 32, the gripping unit 31 is rotated around the central axis O, and the disc substrate 1a is integrally rotated. The rotation speed of the disk substrate 1a by the drive unit 32 is shown in FIG.
As shown in (4), the rotation speed gradually increases, rises, rotates at a constant speed, rotates at a constant speed, and gradually decreases, the rotation speed gradually decreases. The change in the rotation speed of the disc substrate 1a is detected by the rotation speed detecting means 36.
Is detected and input to the discharge control means 35.

When the rotation speed detecting means 36 detects that the rotation speed of the disk substrate 1a has reached a constant speed, the discharge control means 35 outputs a discharge signal to the pump 29 to continuously supply a fixed amount of adhesive from the nozzle portion 29a. And then discharge. The drive unit 32 is assumed to rotate at least once while maintaining a constant speed so that the fixed amount of adhesive discharged from the nozzle unit 29a forms a concentric circle with the central hole CH in the clamp area of the disk substrate 1a that rotates at a constant speed. It is drawn and applied in an annular shape having a diameter larger than that of the central hole CH (Fig. 3).
reference). At the nozzle portion 29a, the ejection of the adhesive is completed when the nozzle portion 29a makes one rotation relative to the disc substrate 1a. After that, the rotation speed of the disk substrate 1a by the drive unit 32 decreases and the drive unit 32 stops. According to this embodiment,
As shown in FIG. 4B, a fixed amount of adhesive is continuously discharged from the nozzle portion 29a of the pump 29 while the disk substrate 1a is rotating at a constant speed as shown in FIG. 4A. It is possible to form a ring-shaped application area Sa in which the application amount and the application width of the adhesive S are evenly continuous. On the other hand, as in the prior art shown in FIG.
When a fixed amount of the adhesive S is discharged from the nozzle portion 29a in the entire area of the rotation operation, the annular coating area Sb is formed as shown in FIG. In this case, the nozzle unit 2
Even if the discharge amount from 9a is fixed, the coating amount and the coating width at the time of rising and falling at a relatively low speed are larger than the coating amount and the coating width at the constant speed, so that the connection portion at the time of starting and ending the discharge In S1, the applied amount and applied width are larger than the other areas.

Therefore, as will be described later, another disk substrate 1b is attached to the disk substrate 1a coated with the shape shown in FIG. 4 (b) according to the embodiment with the adhesive S sandwiched between them and spread. In this case, the outward spreading process can be performed uniformly over the entire circumference of the coating area Sa. Since the upper disk substrate 1b sinks in accordance with the outward spreading of the adhesive S, the distance between the upper disk substrate 1b and the lower disk substrate 1a is narrowed, and the inward spreading can be performed uniformly over the entire circumference. On the other hand, FIG.
When another disk substrate 1b is pasted with the adhesive S sandwiched on the disk substrate 1a coated by the conventional method shown in (b) and spread processing is performed, a connecting portion having a large coating amount and coating width in the coating region Sb. If the outward scattering is detected in S1 and the spreading is finished, there is a drawback that the spreading in other areas becomes insufficient. If spreading is continued until the adhesive has spread all around, the amount of scattering from the connecting portion S1 to the outside increases,
A large amount of adhesive is wasted. Further, as the spread of the adhesive S progresses, the upper disk substrate 1b sinks, so that the adhesive S also spreads inward, but the spread amount is too large at the connecting portion S1 and it sticks out from the central hole CH to the outside. . on the other hand,
If the spreading is stopped in order to avoid the protrusion from the central hole CH, there is a disadvantage that the spreading is insufficient and bubbles are mixed in the regions other than the connecting portion S1.

As described above, the disk substrate 1a coated with the adhesive S moves to the ultraviolet irradiation position B3 as the coating stage B rotates in the direction of the arrow in FIG. Then, the superposed surface of the disk substrate 1a is irradiated with ultraviolet rays from the ultraviolet irradiation device 6 and a reactive species for curing the adhesive S is implanted. Then the disk substrate 1
a is moved to the overlapping position B4. At the superposition position B4, the disc substrate 1b is reversed together with the reversing arm 52, and the disc substrate 1a is arranged parallel to the disc substrate 1a with a predetermined gap in a state where the superposition surface faces the disc substrate 1a. One disc 1 is obtained by superposing them on each other. Incidentally, in the process of moving from B3 to B4 with the rotation of the coating stage B, some kind of process trouble has occurred and the stagnation for a predetermined time or more has occurred after the ultraviolet irradiation, and the disc substrate 1a or the disc 1 has already been cured. Therefore, it is not conveyed to the spreading device 8 and is moved to the defective product delivery position B5 and is removed through the defective product shooter.

The bonded discs 1 are spread by a spreading device 8
It is transported to (8A, 8B). In the spreading device 8, as already described above, the disk 1 is gripped by using the central hole CH and rotated at a high speed in its own circumferential direction, and the adhesive S is spread by using centrifugal force. . As a result, the adhesive S between the disk substrates 1a and 1b is spread in a layer having a uniform thickness. Further, the central holes CH, CH of the disk substrates 1a, 1b
Aligning the axes is performed by matching.

Next, the disk 1 on which the spreading of the adhesive S is finished
1 is conveyed to the disk receiving position C1 on the end surface processing stage C, and is moved to the end surface processing position C2 as the end surface processing stage C rotates in the direction of the arrow in the figure. At the end surface processing position C2, both the front and back surfaces of the disk 1 are flashed by the end surface processing device 9 with light rays including ultraviolet rays and infrared rays. At this time, the end surface of the disk 1 is also irradiated by using a reflection mirror or the like. This allows
The curing of the adhesive S in the vicinity of the end face is accelerated by the ultraviolet rays, and the curing time of the entire adhesive S is shortened by heating with the heat rays. The disk 1 that has undergone the end surface treatment is
The end surface processing stage C is moved to the transfer position C3 by the rotation in the direction of the arrow in the drawing, and is transferred to the flat surface holding device 10 by the transfer arm. Each disc 1 is held in a flat state on the plane holding unit 18 at the loading position D1, and
Through the third elevating devices 14, 15 and 16, the upper, middle and lower peripheral circuits 11, 12 and 13 are sequentially circulated for curing for a predetermined time. Finally, the flat surface holding unit 18 that has returned to the upper circumferential circuit 11 reaches the discharge position D2. During this time, the curing of the adhesive S further progresses, and the bonded disc 1
The shape of is solidified. The disk 1 that has been hardened by the flat surface holding device 10 has the flat surface holding unit 18 at the ejection position D2.
The disk inspection device 19 is removed from the disk.
In the disc inspection apparatus 19, the disc 1 determined to be a defective product is removed from the regular line by the defective product dispensing unit 21, and only the disc 1 determined to be a good product is a non-defective product dispensing unit 20.
Is stacked on the disc holder 2 on the disc stock table E provided in the above, and the disc holder 2 and the disc holder 2 are conveyed to the subsequent process.

As described above, according to the DVD manufacturing apparatus of the present embodiment, the disk substrate 1a is applied by the coating apparatus 5.
By applying the adhesive from the nozzle portion 29a while rotating at a constant speed, it is possible to form an annular application area Sa with a uniform application amount and application width over the entire circumference, and to apply the adhesive during the spreading process. It is possible to spread waste with a uniform film thickness distribution from the inner peripheral edge to the outer peripheral edge while minimizing the waste caused by the scattering.

In the above embodiment, an example in which a cationic polymerization type ultraviolet curable resin composition is used as the adhesive S is shown, but in this case, it is known as a cationic polymerization type ultraviolet curable resin composition. Conventional compositions can be used, for example epoxy resins containing cationic polymerization type photoinitiators. Examples of cationic polymerization type photoinitiators include sulfonium salts, iodonium salts and diazonium salts. In the above embodiment, the method of irradiating the cationic polymerization type UV-curable resin composition after coating the disc substrate 1a and before laminating the disc substrates with ultraviolet rays is described. It may be performed while the cationic polymerization type ultraviolet curable resin composition is dropped from the nozzle portion 29a onto the disk substrate 1a for annular coating during the descent. Further, a radical polymerization type UV curable resin composition may be used as an adhesive instead of the cationic polymerization type UV curable resin composition. In this case, the radical polymerization type UV-curable resin composition may be a known and commonly used one, but it may have two (meth) acryloyl groups such as oligomers such as urethane acrylate and trimethylolpropane triacrylate. It is desirable that the above-mentioned radical polymerization compound and radical polymerization initiator are contained as essential components.

Unlike the case of using the cationic polymerization type ultraviolet curable resin composition, the irradiation of the radical polymerization type ultraviolet curable resin composition with ultraviolet rays is performed after spreading the radical polymerization type ultraviolet curable resin composition. It will be carried out from both sides of the laminated disks. Even in this case, when the coating device according to the present embodiment is used, it is possible to efficiently spread the adhesive without mixing bubbles. Further, the present invention is not limited to the above-mentioned adhesive, and can be applied to a coating method and a coating device when a liquid object containing the adhesive is applied to various objects to be coated or disc-shaped objects. Further, when the adhesive agent is applied, the adhesive S is applied from the nozzle portion 29a by rotating the object to be coated or the disc substrate 1a which is a disk-shaped member with the nozzle portion 29a of the pump 29 fixed. Alternatively, however, the disc substrate 1a may be fixed and the nozzle portion 29a may be rotated at a constant speed in a concentric manner with the central hole CH of the disc substrate 1a to eject the adhesive S. Alternatively, the nozzle portion 29a and the disc substrate 1
a may be rotated at different speeds. In short, the adhesive S may be discharged while the nozzle portion 29a and the disk substrate 1a are relatively rotated or moved at a constant speed.

[0028]

As described above, according to the method and apparatus for applying a liquid object according to the present invention, the application of the liquid object is performed in a state where the relative speed of the discharge port of the liquid object and the object to be coated is substantially constant. Therefore, the uniform and accurate coating amount and coating width of the liquid object can be obtained over the entire coating region.
Further, according to the bonding method and the bonding device for the disk-shaped object according to the present invention, by applying the adhesive while the relative speed between the ejection port of the adhesive and the disk-shaped object is substantially constant, A uniform application amount and application width of the adhesive can be obtained over the entire application area. Therefore, when the disc-shaped objects are pasted together using the above method or device, it becomes possible to spread them uniformly in the circumferential direction of the disc-shaped object after the adhesive is applied uniformly. It is possible to realize a highly bonded state, and it is possible to reduce a partially excessive amount of the adhesive that is scattered and wasted from the end surface of the disk-shaped object. In particular, when laminating a disc that does not transmit ultraviolet rays using a cationic polymerization type ultraviolet curable resin composition, this composition is already irradiated with ultraviolet rays during spreading and curing is in progress, and recovery and reuse are impossible. Therefore, the effect of suppressing the scattering amount is great.

[Brief description of drawings]

FIG. 1 is a schematic overall configuration diagram of a disk manufacturing apparatus according to the present invention.

FIG. 2 is an explanatory view of a main part of a coating device included in the disk manufacturing apparatus shown in FIG.

FIG. 3 is a perspective view of relevant parts showing a state in which an adhesive is applied in the application device shown in FIG.

FIG. 4A is a diagram showing a change in rotation speed of a disk substrate with time, in the embodiment of the present invention;
(B) is a plan view showing an application area of the adhesive on the disk substrate.

FIG. 5A is a diagram showing a change in rotation speed of a disc substrate with time in a conventional example, and FIG. 5B is a plan view showing an application area of an adhesive on the disc substrate. is there.

[Explanation of symbols]

1 disc 1a, 1b Disk substrate (coated object, disk-shaped object) 5 Coating device (laminating device) 6 UV irradiation device (UV irradiation means) 7 Laminating device (laminating means) 8 Spreading device (spreading means) 28 Rotational drive 29 pumps 29a Nozzle part (discharge port) 30 turntable 31 Grasping part (relative rotation means) 32 Drive Unit (Relative Rotation Means) 35 Discharge control means S adhesive (liquid object)

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G11B 7/26 G11B 7/26 F term (reference) 4D075 AC65 AC92 AC94 BB42Z CA13 CA48 DA08 DB13 DB31 DC24 EA07 EA35 EB22 EB33 EB38 4F042 AA02 AA08 BA05 EB09 EB13 EB18 EB29 4J040 PA25 PA32 5D121 AA07 EE22 EE29 FF03 FF18 GG02 GG28

Claims (9)

[Claims] 1. A coating method for applying a liquid object to an object to be coated in an annular shape, wherein the liquid object is applied in a state where the relative rotational speed between the discharge port of the liquid object and the object to be coated is substantially constant. The method for applying a liquid object is characterized in that 2. A coating method in which a liquid object is linearly continuous with an object to be coated and both ends are connected to each other, and a discharge amount of the liquid object from a discharge port is substantially uniform. A method for applying a liquid object, characterized in that the application of the liquid object is performed in a state where the relative speed of the discharge port and the object to be coated is substantially constant. 3. A bonding method in which two disk-shaped objects are bonded together via an adhesive, wherein the adhesive ejection port and the disk-shaped object are rotated relative to each other.
A step of applying the adhesive in an annular shape on the inner peripheral portion of at least one of the disk-shaped objects, and after bonding the two disk-shaped objects with the adhesive sandwiched therebetween And a spreading step of spreading the adhesive by rotating the adhesive in the applying step while the relative rotation speed between the ejection port of the adhesive and the disk-shaped object is substantially constant. A laminating method characterized in that it is applied to a disk-shaped object. 4. The bonding method according to claim 3, wherein the adhesive is a cationic polymerization type ultraviolet curable resin composition. 5. The disk-shaped object is a disk substrate,
The bonding method according to claim 3, wherein two disk substrates are bonded together to form a disk. 6. A coating device for annularly applying a liquid object to an object to be coated, comprising: a discharge port for discharging the liquid object; a relative rotating means for relatively rotating the discharge port and the object to be coated; A coating device for a liquid object, comprising: a discharge port and a discharge control unit that discharges the liquid object from the discharge port in a state where the relative rotational speed of the object to be coated is substantially constant. 7. An object to be coated, sandwiching the liquid object 2
7. The liquid object coating apparatus according to claim 6, further comprising spreading means for spreading the liquid object by rotating after laminating the disk-shaped objects. 8. A laminating apparatus for laminating two disk-shaped objects by using a cationic polymerization type ultraviolet curable resin composition as an adhesive, the ejection port ejecting the adhesive, and the ejection port. Relative rotation means for relatively rotating the disc-shaped object, ejection control means for ejecting the adhesive from the ejection port while the relative rotational speed of the ejection port and the disc-shaped object is substantially constant, and the disc-shaped object UV irradiating means for irradiating the adhesive with ultraviolet rays in a state where the adhesive is applied to the adhesive, bonding means for bonding the two disk-shaped objects with the adhesive irradiated with the ultraviolet rays sandwiched therebetween, and two circles A laminating apparatus comprising: a spreading means for spreading an adhesive agent interposed between plate-like objects. 9. The disk-shaped object is a disk substrate,
9. The laminating apparatus according to claim 8, wherein two disc substrates are laminated to form a disc.