JP3469138B2 - Optical disc bonding method and apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminating apparatus for laminating an optical disk substrate having an information recording layer having a conductive thin film as a reflective layer with an adhesive to make one optical disk.

[0002]

2. Description of the Related Art Disc bonding will be described as a conventional example. In an optical disc laminating apparatus using a liquid adhesive, it is necessary to prevent voids (air bubbles) in the adhesive layer after laminating. Is important, and various methods have been considered for that purpose. However, all methods are voids or diameters with a diameter of about 0.1 mm or more.
Minute voids of 0.05 mm to 0.1 mm or less or mixed voids are formed between the disk substrates.

As a method capable of considerably improving such a conventional method, the present applicant has filed a patent application for the following invention (Japanese Patent Application No. 10-257530). The invention of this application will be described with reference to FIG.

Of the two disk substrates A and B, the adhesive surface of the lower disk substrate A is faced up, and the annular adhesive liquid film a is formed there. On the bonding surface of the upper disk substrate B, a plurality of dot-shaped adhesive liquid films b are formed on a virtual circle having a diameter slightly larger than or similar to the diameter of the annular adhesive liquid film a. After that, the two disc substrates A and B are brought close to each other with their adhesive surfaces facing each other, and the annular adhesive liquid film a and the dot-shaped adhesive liquid film b are brought into contact with each other to make two disc substrates A. , B on top of each other. Next, two disk substrates A and B
Is spun to spread the adhesive liquid film a and the adhesive liquid film b, and the excess adhesive is shaken off to form an adhesive layer having a uniform film thickness between the disk substrates A and B.

That is, on the outside of the annular adhesive liquid film a on the surface of the lower disk substrate A, the upper disk substrate B is placed.
By appropriately contacting the tops of the dot-shaped adhesive liquid films b on a virtual circle on the surface, it is possible to prevent the occurrence of voids, particularly minute voids, which occur at the moment when these liquid films contact each other, and When the contact portion spreads over the entire liquid film, air between the liquid films can be eliminated, so that the occurrence of voids at this time is reduced.

[0006]

However, even with such a method, it is extremely difficult to sufficiently reduce the contact area at the moment when the adhesive liquid film a and the adhesive liquid film b contact each other. You can't eliminate all such voids.

Accordingly, the present invention provides an optical disk substrate bonding apparatus and method in which, when two disk substrates are bonded together with an adhesive, virtually no voids are generated or hardly generated between them. It is an issue.

[0008]

In order to solve the above problems, the invention of claim 1 provides at least one optical disk.
Adhesive is applied to the substrate, and the one light is applied by the adhesive.
Laminate the disk substrate and the other optical disk substrate
Before stacking both optical disk substrates,
Applying a voltage between both optical disk substrates
An electric field is formed in the
Small contact area by tapering the top of the liquid film
The optical disk substrates on both sides,
A method for laminating optical discs, which comprises:
The voltage applied between the two optical disk substrates is
After the adhesives have come into contact with each other, or when the adhesives
After starting liquid contact with the other optical disk substrate,
It is intended to provide a method for laminating optical discs , in which the time until liquid contact is completed is kept at a predetermined value or more.

In order to solve the above-mentioned problems, the invention of claim 2 applies an adhesive to at least one optical disk substrate.
The optical disk substrate and the other optical disk substrate are bonded by the adhesive.
When attaching the optical disk substrate of
Before stacking the disc substrates, both optical discs
Voltage is applied between the substrates to form an electric field in the space,
The top of the liquid film of the adhesive is tapered by electrostatic attraction by the electric field
By reducing the contact area,
How to stick optical discs on top of each other
A method, when the liquid contact of the adhesive is completed,
After equalizing the potentials of both optical disk substrates,
An optical disk bonding method for spin-processing the optical disk substrate is provided.

In order to solve the above-mentioned problems, the invention of claim 3 provides the invention according to claim 2, wherein the potential is substantially the ground potential.
A method for laminating optical disks is provided.

In order to solve the above-mentioned problems, the invention of claim 4 applies an adhesive to at least one optical disk substrate.
The optical disk substrate and the other optical disk substrate are bonded by the adhesive.
When attaching the optical disk substrate of
Before stacking the disc substrates, both optical discs
Voltage is applied between the substrates to form an electric field in the space,
The top of the liquid film of the adhesive is tapered by electrostatic attraction by the electric field
By reducing the contact area,
An optical disk that spins optical disk substrates
A click bonding apparatus, a pair of electrodes and support means for supporting to apply a voltage to the two optical disk substrates respectively, and a power source for applying a voltage between the electrodes of the electrode-and-bearing means, said a closed circuit including the power supply and the two optical disk substrates and the ground is to provide an optical disk bonding apparatus and a resistance means connected in series.

In order to solve the above-mentioned problems, the invention of claim 5 relates to claim 4, wherein the liquid film of the adhesive is in contact with the liquid.
Is the time from the start of
Then , when the time until the voltage V1 between the reflective films decreases to the critical voltage V2 at which the effect of voltage application is obtained with the completion of the liquid contact is T2, the resistance means is T1.
An optical disk laminating apparatus having a resistance value that gives a time constant satisfying <T2.

In order to solve the above-mentioned problems, the invention of claim 6 provides the method according to claim 4, wherein the time from the start of the contact of the liquid film of the adhesive to the end of the contact is T1. And, when the time until the voltage V1 between the reflective films decreases to the critical voltage V2 at which the effect of voltage application is obtained with the completion of the liquid contact is T2, the electrode / bearing means is T1. The present invention proposes an optical disk laminating apparatus made of a material having a resistance value that gives a time constant that satisfies <T2.

In order to solve the above-mentioned problems, the invention of claim 7 resides in any one of claims 4 to 6.
Then, when the liquid contact of the liquid film of the adhesive is completed, the electrode / supporting means is disconnected from the power source, and an optical disk laminating apparatus provided with a switch mechanism for connecting the electrode / supporting means to each other is proposed. Is.

[0015]

First, the principle of the present invention will be described. The present invention is based on the finding that when the liquid film of the adhesive formed on the upper and lower optical disk substrates first comes into contact, the smaller the contact area, the more difficult it is to form minute voids. By forming it in the space between them, the top of the liquid film of the adhesive is tapered by the attractive force of the electric field, and the initial contact area is made sufficiently small.

Further, by applying positive and negative charges having different polarities to the upper and lower discs and the liquid film by the electric field, the liquid film and the optical disc resulting from the combination of the positive and negative charges when the liquid films come into contact with each other. The spreadability between the substrate and the substrate is improved and the generation of voids is further suppressed.

As a generally known digital versatile disc (DVD), a single-sided single-layer type optical disc having a recording layer including a pit row and a reflective layer only on one optical disc substrate to be laminated, both laminated Double-sided single-layer type optical disc having a recording layer on the optical disc substrate, or one-sided two with one reflecting layer made of a semitransparent film
There is a layered optical disc or a double-sided dual-layered optical disc in which two single-sided dual-layered optical discs are stuck together, and the present invention can be applied to the production of these various types of DVDs.

An embodiment according to the present invention will be described below with reference to the drawings. In this embodiment, the voltage applied between the optical disk substrates via the electrodes exists as an effective value for a certain period between the reflection films.

As shown in FIG. 1, the lower optical disk substrate A is placed on the electrode 1 of the electrode / bearing means which also functions as a pedestal, and the upper optical disk substrate B is the electrode 2 of the electrode / bearing means. Supported by. Optical disk substrate A,
Each B has a normal recording layer (not shown) on one surface, and reflective films A ′ and B ′ formed thereon. These reflective films
Optical disk substrate A so that A'and B'face each other with a gap.
, B are supported by the electrodes 1 and 2 of the electrode / bearing means. The optical disk substrates A and B respectively have central holes X and Y having substantially the same diameter, and the reflective films A ′ and B ′ generally have central holes X and
It has an inner diameter larger than Y and also has an optical disc substrate A.
, B has a smaller outer shape than that of B.

In FIG. 1, only those electrodes 1 and 2 are shown as the electrode / bearing means, and the optical disk substrate thereof is shown.
The surface in contact with A and B is a smooth flat plate. Also,
Although not shown in FIG. 1, the electrodes 1 and 2 of the electrode / bearing means are not shown.
Has ordinary suction holes for sucking and holding the optical disk substrates A 1 and B 2, respectively, and the plurality of suction holes are coupled to a suction mechanism (not shown). The electrodes 1 and 2 of the electrode / bearing means have inner diameters about the diameters of the central holes X 1 and Y 2 of the optical disk substrates A 1 and B 2 or larger than that, and a reflective film A ′,
The outer diameter is about the same as or smaller than the outer diameter of B '.

The electrode 1 of the electrode / bearing means is selectively connected to the DC power source 4 or the ground by the switch 3, and the electrode 2 of the electrode / bearing means is fixed to the ground. Therefore, when the DC output voltage of the DC power supply 4 is V and the switch 3 is closed to the contact 3a side, the voltage V is applied between the electrodes 1 and 2 of the electrode / bearing means via the switch 3 and the resistance means Rd. It Here, the electrode 1 serving as the electrode / bearing means, the reflective film A ′, and the insulating material of the optical disk substrate A form a capacitance C1. The reflective films A'and B'and the air gap between them form a variable capacitance C2. Further, the reflective film B ', the electrode 2 of the electrode / bearing means and the insulating material of the optical disk substrate B sandwiched therebetween form a capacitance C3. However, these capacitances C1-C3 are connected in series as shown in FIG. For example, capacitances C1 and C3 are 150-20
Capacitance C2 of 0 pF, just before the liquid films of both adhesives come into contact with each other, is about 50 pF, which are both very small. Note that stray capacitance, which cannot be determined by design, is ignored here.

As shown in FIG. 3, liquid films a 1 and b 2 of an adhesive are provided on the reflection films A ′ and B ′ of the disk substrates A and B, respectively. A continuous annular liquid film is formed on the lower optical disk substrate A.
a is formed, and discontinuous liquid films b are formed on the upper optical disk substrate B at substantially constant intervals in a virtual circle indicated by a chain line b ′. Here, the diameter of the center of the continuous annular liquid film a of the lower optical disc substrate A is D, and the diameter of the virtual circle shown by the chain line b ′ of the upper optical disc substrate B is D, which are equal to each other. .

Next, with reference to FIG. 4 to FIG. 7, an embodiment of optical disk bonding by a voltage application method will be described. The electrode 1 of the electrode / bearing means which also functions as a pedestal is fixed to a center shaft 5 projecting at the center thereof. A side wall of the center shaft 5 is divided into a plurality of pieces so that the chuck claws, which will be described later, can be passed through when the expansion and contraction operations are performed. The electrode 1 of the electrode / bearing means is fixed to an elevating shaft 6 coaxial with the center shaft 5, and although not shown, the electrode 1 of the electrode / bearing means is moved as the elevating shaft 6 is moved up and down by a driving device. Also moves up and down, for example, an optical disk substrate A placed on each window of the turntable
In the process of ascending, the electrode 1 of the electrode / bearing means receives and ascends to the position shown.

The electrode 1 is selectively connected to the negative terminal of the DC power source 4 by the switch 3, the resistance means Rd and the conductor 7. The positive terminal of the DC power source 4 is grounded. The voltage value of the DC power source 4 causes the tip portions of the liquid film a and the liquid film b of the adhesive to be deformed into a tapered shape immediately before the liquid film a and the liquid film b of the adhesive are contacted with each other, and the liquid films a and b of the adhesive are wet. The value is set to a value equal to or higher than the voltage that improves and spreads the property, and equal to or lower than the voltage at which discharge does not occur between the electrode / bearing means.

The flat plate-shaped electrode 2 of the electrode / supporting means for supporting the upper optical disk substrate B is provided with a general suction tool (not shown), and the suction operation of the upper optical disk board is performed by the suction tool.
Adsorb and hold the upper surface of B. Electrode 2 of electrode and bearing means
Is connected to a transfer arm that can swivel horizontally at an angle (not shown), and is grounded through the transfer arm or the like.

The electrode 2 of the electrode / bearing means is fixed at its center to the chuck means 8 having an axis centered on the axis of the center shaft 5 of the lower electrode / bearing means. Chuck means 8
Has three chuck claws 9 which are operated by an external signal and perform expansion / contraction diameter operation. The chuck claw 9 expands the optical disk substrates A and B in the central hole X of the optical disk substrates A and B before transferring them to another place while holding the stacked state. It supports the inner walls of A and B, and its operation will be described in detail later.

Next, the bonding of the optical disk substrates will be described while explaining the operation of this mechanism. At least the upper optical disk substrate B is the electrode 2 of the electrode and bearing means.
In the state of being sucked and held at, the discontinuous liquid films b are formed on the lower surface at substantially different intervals in a virtual circle at another position as shown in FIG. While the lower optical disk substrate A is placed on the electrode 1 of the electrode / bearing means, a continuous annular liquid film a is formed on the upper surface thereof. The positional relationship between the liquid film a and the liquid film b is as shown in FIG. Next, a transfer arm (not shown) connected to the electrode 2 of the electrode / bearing means performs a pivotal movement to convey the electrode 2 of the electrode / bearing means to the position shown in FIG. 5 and stop it.

Next, as shown in FIG. 4, the lifting shaft 6
The electrode 1 of the electrode / bearing means is lifted by raising the angle, and the electrode 1 of the electrode / bearing means and the electrode 2 of the electrode / bearing means start to approach each other, and when the set distance is approached, the switch 3 is closed. As a result, the voltage V 3 of the DC power supply 4 is applied between the electrodes 1 and 2. Along with this, as described above, a certain proportion of the voltage V 2 is applied between the reflective films A ′ and B ′ of the optical disk substrates A and B. Therefore,
An electric field is formed in the space between the reflective films A'and B '. Here, the approach speed is preferable because the bonding time per one optical disk substrate can be shortened as long as it does not affect the speed control when the liquid films of the adhesive are brought into contact with each other, which will be described below. Is not particularly limited. Since the flowing current is very small, the voltage applied between the reflection films A ′ and B ′ due to the connection of the resistance means Rd is not substantially affected.

By applying the voltage, the liquid film a of the adhesive
The liquid film b and the liquid film b have opposite charges, and when they attract each other, the top of the liquid film a and the tip of the liquid film b tend to taper. Then, as the space between the optical disk substrates A and B narrows, the electric field in that space increases, and the liquid film a
When liquid comes into contact with liquid film b, the attractive force due to the electric field is maximized, and the top of liquid film a and the tip of liquid film b are further tapered,
Since the top of the tapered liquid film a and the tip of the liquid film b first come into contact with each other, the area at the moment of contact between the liquid film a and the liquid film b is significantly smaller than in the conventional case.

The state after this contact is shown in FIG. When the top of liquid film a and the tip of liquid film b contact, the negative and positive charges of liquid film a and liquid film b are neutralized to improve wettability, resulting in discontinuous liquid film b. Rapidly spreads along an annular continuous liquid film a, and liquid films a and b together form an annular liquid film, and positive and negative charges remain on the optical disk substrates A and B. Radiation spreads inward and outward.

Now, if the resistance means Rd, which is an important component of the present invention, is not connected, there are the following problems. In the present invention, as shown in FIG. 3, since the liquid film of the adhesive is supplied in a dot shape to at least one optical disk substrate, there is no problem if all these dot-shaped liquid films come into contact with liquid at the same time. The liquid contact time of these dot-like liquid films varies depending on the height difference of the dot-like liquid films, the flatness of the optical disk substrate, the parallelism of the pair of optical disk substrates, and other conditions.

First, when liquid films of the adhesive are brought into contact with each other at one point or a plurality of points, the charge of the capacitance C2 between the reflection films A ′ and B ′ is discharged through the resistance of the adhesive at the contacted portions. Starts and the voltage V1 between the reflective films A'and B'at a certain discharge time constant.
Drops at a certain point, and becomes lower than the minimum value that makes this voltage application effective, that is, the critical voltage V2, and the effect of this voltage application almost disappears when the liquid film of another adhesive comes in contact with it. . Here, the resistance of the adhesive is generally as large as several tens of MΩ or more, but as described above, the capacitance is
Since C2 is very small, the discharge time constant is small.

Therefore, in the present invention, the adhesive liquid films a and b are first contacted with each other at one point or a plurality of points from the time when the contact between the adhesive liquid films a and b is first started. The time until the liquid contact of the adhesive is completed is T1, and the voltage V1 between the reflective films A'and B'is the voltage from the time when the liquid contact between the adhesive liquid films a and b starts at one or more points. The minimum value that makes the application effective, that is, the time until it drops below the critical voltage V2
When T2 is set, one of the characteristics is that a charging time constant that satisfies T1 ≦ T2 is given. For example, as a resistance means Rd that gives such a charging time constant, from the experimental point of view, a value of several tens MΩ to 300 MΩ or less is used. A resistance element with a resistance value in the range
It is connected to a closed circuit including ground, power supply 4, switch 3 and electrodes 1, 2. If the resistance value is too small, the time V2 until the voltage V1 between the reflective films A ′ and B ′ drops to the critical voltage V2 or less cannot be sufficiently suppressed from generating voids, and is also too large. Since the voltage V1 between the reflective films A'and B'decreases sharply to the critical voltage V2 or less and the time constant is greatly extended at a voltage level lower than the critical voltage V2, the occurrence of voids cannot be sufficiently suppressed. .

As described above, when the top of the liquid film a and the tip of the liquid film b come into contact with each other, the reflection film A ′ as shown in FIG.
The charge of the capacitance C2 between B'is discharged through the resistance of the adhesive, and conversely the capacitances C1 and C3 are charged by the power source 4 through the resistance means Rd and the switch 3 ground,
By connecting the resistance means Rd, particularly one having a resistance value satisfying the above-mentioned conditions, to the charging path of the capacitances C1 and C3, the charging speed of the capacitances C1 and C3, that is, the voltage rise is slowed. Therefore, the voltage drop rate between the reflection films A ′ and B ′ becomes slower, and at the first point or a plurality of points, the point at which the liquid films a and b of the adhesive start to come into contact with each other finally becomes one or a plurality of points. Thus, the voltage between the reflection films A ′ and B ′ can be maintained at a value equal to or higher than the critical voltage until the liquid contact between the adhesive liquid films a 1 and b 2 is completed.

Continuing the description of the bonding, the chuck claws 9 are attached to the optical disk substrate A after the liquid contact of the entire surfaces of the adhesive liquid films a and b is completed.
The diameter expansion operation is performed in the center holes X of B and B, and the inner walls of the optical disk substrates A and B are pressed and held as shown in FIG. Then, the switch 3 is switched to the contact 3b to cut off the power supply voltage, and at the same time, the electrode 1 is connected to the ground voltage, and after the voltage between the electrode 1 and the electrode 2 becomes almost zero, the elevating shaft 6 performs the descending operation. Since the electrode 1 of the electrode / supporting means is lowered, the optical disk substrates A and B are held by the chuck means 8 and supported on the electrode 2 side of the electrode / supporting means. Thus, since the electrodes 1 and 2 are separated after the voltage between the electrodes 1 and 2 has become almost zero or a low voltage value,
No discharge occurs between them.

After that, the electrode 2 of the electrode / supporting means performs a turning motion together with the optical disk substrates A and B by a turning means (not shown) to transfer the optical disk substrates A and B to a spinner device (not shown). It is placed, and the centrifugal force causes it to have a uniform film thickness, and unnecessary adhesive is shaken off. By this spin processing, the reflection film A'of the optical disk substrates A and B
An adhesive layer having a uniform void-thickness setting is formed between B '. Of course, the spin process may be performed at the same place as the bonding position.

In the above embodiment, a resistance means such as a resistor is connected between the switch 3 and the DC power source 4 in order to lengthen the charging time constant. However, the electrodes 1 and 2 are made of stainless steel plate. It may be made of a high resistance material layer having a resistance value in the above range without being made of a metal. Suitable as such a high resistance material, a polymer resin having conductivity which is relatively mechanically tough and easy to process, or various resins obtained by adding or doping a conductive substance such as metal particles. and so on.

In this embodiment, it is assumed that the diameter of the center of the continuous annular liquid film a of the lower optical disc substrate A and the diameter of the virtual circle shown by the chain line b ′ of the upper optical disc substrate B are equal to each other. As described above, the diameter of either one may be somewhat larger, and the effect of the present invention can be obtained even if the liquid film is formed only on one of the optical disk substrates. Further, even if the adhesives are discontinuously formed on both optical disk substrates in a dotted line shape, the effect of the present invention can be similarly obtained if the distance between the liquid films adjacent to each other is relatively small.

[0039]

As described above, according to the present invention, when the optical disk substrates are bonded together, the tip portion of the liquid film of the dot-like adhesive is entirely covered while the voltage between the reflective films does not drop below an effective value. Since the liquid film of the other adhesive is brought into contact with the liquid, the adhesive is brought into contact with the liquid in a very preferable state, and it is possible to significantly suppress the formation of voids between the bonded objects, which can be suppressed. It is possible to obtain a high quality optical disk which is few or does not substantially exist.

[Brief description of drawings]

FIG. 1 is a diagram for explaining optical disc bonding according to the present invention.

FIG. 2 is a diagram for explaining a relationship of capacitances in optical disk bonding according to the present invention.

FIG. 3 is a diagram showing an example of supplying an adhesive for explaining the optical disc bonding according to the present invention.

FIG. 4 is a diagram for explaining an embodiment of optical disc bonding according to the present invention.

FIG. 5 is a diagram for explaining an embodiment of optical disc bonding according to the present invention.

FIG. 6 is a diagram for explaining an embodiment of optical disc bonding according to the present invention.

FIG. 7 is a diagram for explaining an example of an embodiment of laminating optical disks according to the present invention.

FIG. 8 is a diagram for explaining a conventional optical disc bonding method.

[Explanation of symbols]

1, 2 ... Electrodes serving as electrodes and supporting means 3 ... switch 4 ... DC power supply 5 ... Center shaft of lower electrode and bearing means 6 ... Lifting shaft 8: chuck means A, B ・ ・ ・ Optical disk substrate A ', B' ... Reflective film on optical disk substrates A and B a, b ... Adhesive liquid film Rd: resistance means

Front Page Continuation (72) Inventor Koji Yamaguchi 1-1-18 Takada, Toshima-ku, Tokyo Orijin Electric Co., Ltd. (72) Masahiko Kotoyori 1-1-18 Takada, Toshima-ku, Tokyo Orizin Electric Co., Ltd. In-house (56) Reference JP-A-7-228847 (JP, A) JP-A-8-36791 (JP, A) JP-A-63-49424 (JP, A) JP-A-64-14752 (JP, A) ) Japanese Patent Laid-Open No. 10-312591 (JP, A) Patent 3362016 (JP, B2) (58) Fields investigated (Int.Cl. ⁷ , DB name) G11B 7/26

Claims (7)

(57) [Claims] 1. Adhesion to at least one optical disk substrate
Agent is applied, and the optical disc substrate of the one side is applied by the adhesive.
When bonding the plate and the other optical disk substrate,
Before stacking both optical disk substrates,
A voltage is applied between the optical disk substrates to form an electric field in that space.
And the top of the liquid film of the adhesive by electrostatic attraction by the electric field
The contact area is reduced by tapering the
Both optical disc substrates are stacked and spin processed.
In the optical disk laminating method, the voltage applied between the two optical disk substrates is
After the adhesives have come into contact with each other, or
Does the adhesive start contacting the other optical disk substrate?
From the above, the method for laminating optical disks is characterized in that the liquid is held at a predetermined value or more until the contact with the liquid is completed . 2. Adhesion to at least one optical disk substrate
Agent is applied, and the optical disc substrate of the one side is applied by the adhesive.
When bonding the plate and the other optical disk substrate,
Before stacking both optical disk substrates,
A voltage is applied between the optical disk substrates to form an electric field in that space.
And the top of the liquid film of the adhesive by electrostatic attraction by the electric field
The contact area is reduced by tapering the
Adhesion of optical discs by superposing both optical disc substrates
A method of combining, wherein when the liquid contact of the adhesive is completed, both of the light
The potential of the disk substrate is made equal, and then the optical disk
An optical disk laminating method characterized by spin-treating a substrate . 3. The optical disk bonding method according to claim 2, wherein the potential is substantially a ground potential . 4. Adhesion to at least one optical disk substrate
Agent is applied, and the optical disc substrate of the one side is applied by the adhesive.
When bonding the plate and the other optical disk substrate,
Before stacking both optical disk substrates,
A voltage is applied between the optical disk substrates to form an electric field in that space.
And the top of the liquid film of the adhesive by electrostatic attraction by the electric field
The contact area is reduced by tapering the
Both optical disc substrates are stacked and spin processed.
An optical disk laminating apparatus, comprising: a pair of electrodes / supporting means for applying and supporting a voltage to each of the two optical disk substrates; and a power supply for applying a voltage between the electrodes of the electrodes / supporting means, optical disc bonding apparatus characterized by comprising a resistor means connected in series, to the closed circuit including the power supply and the two optical disk substrates and the ground. 5. The liquid contact according to claim 4, wherein the liquid contact of the liquid film of the adhesive is started after the liquid contact is started.
When the time until the end is T1, and the time until the voltage V1 between the reflective films is reduced to the critical voltage V2 at which the effect of voltage application is obtained with the end of the liquid contact is T2, The optical disk bonding apparatus, wherein the resistance means has a resistance value that gives a time constant that satisfies T1 <T2. 6. The method according to claim 4, wherein the liquid contact of the liquid film of the adhesive is started after the liquid contact is started.
The time until the end is T1
As a result, the voltage V1 between the reflective films has the effect of voltage application.
The time until the critical voltage V2 is reduced to V2 is T2.
At this time, the electrode / bearing means satisfies T1 <T2.
Be made of a material that has a resistance value that gives such a time constant.
Characteristic optical disk laminating device. 7. The method according to any one of claims 4 to 6.
In the optical disc bonding method described above, a switch mechanism is provided for disconnecting the electrode / bearing means from the power source and connecting the electrode / bearing means to each other when the liquid contact with the liquid film of the adhesive is completed. apparatus.