JPH05242533A - Production of optical type combined disk and its device - Google Patents

Abstract

(57) [Abstract] [Purpose] The adhesion between the bonded discs is increased, air bubbles are prevented from remaining, corrosion of the aluminum reflective film due to penetration of moisture etc. into the adhesive layer is eliminated, and information pits may be damaged. Provided is a method for manufacturing an optical bonded disc without a device, and an apparatus therefor. [Structure] One adhesive surface of the two disks A to be bonded is turned upward, and this is rotated, and the adhesive 8 is dropped while moving the nozzle 2 to apply the adhesive 8 to a spiral adhesive application locus. Then, the other disk A is placed with the adhesive surface facing downward, and the disks are stacked and housed between the upper and lower vacuum chambers 13 and 15. The vacuum pump 16 evacuates this to bond the pressure plate 1.
The disc A is bonded by pressing with 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disc such as a video disc, in which two discs having optical information recorded thereon are superposed and adhered to each other so that signals can be reproduced on both sides. And a device for manufacturing the bonded disc.

[0002]

2. Description of the Related Art Conventionally, a video disc on which information is optically recorded has information pits formed on one surface of a disk made of a transparent plastic material such as acrylic resin. A metal reflective film is formed by means, and a protective film or an adhesive is applied on the metal reflective film,
The surfaces coated with the adhesive are superposed on each other, and two discs are stuck together to form one optical video disc.

When laminating a laminated disc such as the above-mentioned video disc, a hot-melt type adhesive is applied by a roll coater, two coated discs are superposed and pressed by a press to adhere them. Was there.

[0004]

However, on the surface of the adhesive applied by the roll coater, a myriad of application stitch patterns called roll stitches are formed with unevenness, which causes unevenness in the coating thickness. I will end up.

When two discs having such uneven coating thickness are overlapped and adhered, innumerable unevenness of the coating pattern causes
Innumerable voids are created between the adhesive layers, which remain as bubbles after bonding, which not only reduces the adhesive strength, but also
Due to a change in the ambient temperature of the bonded discs, peeling or deformation may occur during long-term use, and air or moisture diffuses by sewing the voids of the adhesive.

This diffused substance, especially water, causes hydrolysis of the adhesive, resulting in a decrease in adhesive strength over a long period of time, increasing the risk of peeling, and the diffused water is
There is also a problem of attacking the aluminum reflection film.

Further, in order to apply a hot melt type adhesive with a roll coater, it is necessary to use a metal roll because of its heating property and spreadability, and hard foreign substances are mixed in the adhesive. Then, when the adhesive is applied to the disc, the foreign matter is pressed against the pit surface by the metal roll to damage the pit of the disc, or the metal roll is damaged, and the damaged metal roll further damages the pit surface. There were also drawbacks such as doing.

The present invention solves the above-mentioned problems that occur during the manufacturing process of a conventional optical laminated disc, and reduces the adhesive force, peels off, is deformed, and has an aluminum reflective film even when it is used for a long period of time. An object of the present invention is to provide a method for manufacturing an optical laminated disc excellent in durability without the risk of corrosion and damage to information pits, and an apparatus therefor.

[0009]

SUMMARY OF THE INVENTION The present invention relates to a method of manufacturing an optical laminated disc for achieving the above-mentioned object, which method comprises optically recording and laminating information.
Adhesive is applied to at least one bonding surface of one disk in a locus such that the portion between the adhesives which is not applied, such as a spiral shape, is continuous to at least one of the center side and the outer peripheral side of the disk. The laminating surfaces of the discs are overlapped with each other, the air in the portion between the loci is evacuated, and then the two discs are pressure-bonded to solidify the adhesive.

Further, the present invention also relates to means of an apparatus for producing an optical laminated disc by the above-mentioned production method, which means is for laminating at least one of two discs to be optically recorded and laminated. A coating means for coating the surface of the disk with a locus such that a portion between the uncoated adhesives such as a spiral is continuous with at least one of the center side and the outer peripheral side of the disk, and the bonding surface of at least one disk A superimposing means for superposing the bonding surfaces of the two discs coated with the adhesive along the locus, a vacuum evacuation means for evacuating the air between the loci, and the two evacuated discs. And a fixing means for solidifying the adhesive by pressing the disk.

[0011]

The operation of the optical laminated disc according to the present invention is as follows.
Since the part between the adhesive application loci is continuous to at least one of the center side and the outer peripheral side of the disc, the air in this part can be completely removed by the vacuum evacuation means, and the two discs can be bonded together. The adhesive applied by crimping is spread over the entire bonding surface, and in particular, the entrance between the loci is closed.

Therefore, there is no possibility that air will remain between the bonded two discs, or that air or moisture will enter, and the decrease in adhesive strength, peeling, and corrosion of the aluminum reflective film can be prevented.

Further, since the adhesive is applied to such a locus by dropping without using a roll coater, foreign matters mixed in the adhesive as in the case of applying by a roll coater. Or, there is no possibility of damaging the pits of the disc with the metal roll.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an example of the embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows one embodiment of the present invention including a disk A conveying device, and FIG. 2 shows a second station II of FIG.
4 is a third station of FIG. 1, and FIG. 3 shows an adhesive application locus by the adhesive application apparatus.
The vacuum and pressure bonding device 5 of the disk A which is III is shown.

The disk A loaded in FIG.
An information pit is formed on one surface of a disk made of a plastic material such as MMA, an aluminum reflection film is formed on the pit surface, and a protective film is formed on the reflection film, for example, an ultraviolet-curing type Dainippon Nihon. EX-252 manufactured by Kagaku Kogyo Co., Ltd. is spin-coated to a thickness of about 10 μm.

In FIG. 1, at the first station I, the disk A has its pit surface facing upward,
The pit surface is supplied so that the adhesive is applied, and the supplied disk A is applied to the second station II by the rotating arm 1 for adsorbing the disk A.
Then, the disk A coated with the adhesive at the second station II is sequentially transported to the third station III.

The adhesive applying device shown in FIG. 2 is a device for moving a motor 7 on which the disk A conveyed by the rotating arm 1 is placed and rotated, and a disk A rotated by the motor 7 for moving the same. 3, a nozzle 2 for dropping the adhesive while moving at a constant speed from the inner circumference to the outer circumference, a tank 9 for containing the dropped adhesive 8, and a nozzle for pumping up the adhesive 8 in the tank 9 2 and a valve 4 for controlling the discharge of the adhesive 8 sent by the pump 10 from the nozzle 2.

The coating locus on the disk A which is coated by this adhesive coating device is a constant speed movement from the inner circumference to the outer circumference of the nozzle 2 while the disk A rotates, as shown in FIG. When the protective film is the above-mentioned EX-252, a hot melt type PPET2 manufactured by Toa Gosei Kagaku Kogyo Co., Ltd. is used as the adhesive 8.
101 is used.

The center inner diameter is 35 mmφ and the outer diameter is 30
In the case of a 0 mmφ video disc, the rotation speed of the disc A is 50 rpm and the discharge amount of the adhesive 8 is 0.07 ml / s.
Then, discharge is started from the radius r of the disk A = 20 mm,
The velocity v in the outer diameter direction of the nozzle 2 is 4.2 mm / s at the initial velocity,
Gradient -0.12 mm / s, move to r = 148 mm,
Discharging is completed and coating is performed.

The coated disk A is conveyed to the third station III by the rotary arm 1 as described above. At the end of the conveyance, the adhesive-coated disk A is transferred to the third station III. After unloading, the rotating arm 1 transfers the disk A, which is supplied to the first station I with the protective film provided on the pit surface as the lower surface, to the third station III, and Place on top.

In this third station III, as shown in FIG. 4, a lower vacuum chamber 1 provided with a mounting table 12 on which a guide pin 11 into which the center hole of the disk A is inserted is erected.
5 is provided, and the two discs A conveyed by the rotating arm 1 are superposed on each other without eccentricity by inserting the center hole into the guide pin 11.

When this superposition is completed, the rotary arm 1
, The upper vacuum chamber 13 descends and the lower vacuum chamber 15
Although joined to the upper side, since the packing 14 is interposed between the lower vacuum tank 15 and the upper vacuum tank 13, both vacuum tanks 1
The insides of 3 and 15 are shut off from the outside air.

In this state, by operating the vacuum pump 16 connected to the lower vacuum tank 15 and opening the valve 17 between the lower vacuum tank 15 and the vacuum pump 16, the insides of both vacuum tanks 13 and 15 are in a vacuum state. When the air between the application loci of the adhesive 8 is also sucked out and a vacuum state is reached, the pressure bonding plate 18 provided in the upper vacuum chamber 13 is lowered.

By the downward movement, the upper surfaces of the two stacked disks A are pressed, and the adhesive 8 applied to the disks A by the pressing is spread so as to be diffused between the two disks A. Then, the two disks A are bonded.

When the bonding is completed, the pressure plate 18 is raised to release the pressure on the disk A, and then the valve 17 is closed and the leak valve 19 for connecting the insides of both vacuum chambers 13 and 15 to the atmosphere. When is opened, the atmosphere is introduced into both vacuum chambers 13 and 15, and the vacuum state is lost.

After raising the upper vacuum chamber 13, the moving arm 6 of the fourth station IV in FIG. 1 is operated,
This is moved onto the lower vacuum chamber 15 to adsorb the adhered disk A, and the moving arm 6 is moved to move the lower vacuum chamber 15 to the lower vacuum chamber 15.
Then, the disk A is taken out, the adhesive 8 is solidified, and the laminating work is completed.

In this way, the bonded disk A is subjected to finishing processing of the outer peripheral edge of the disk described in, for example, Japanese Patent Application Laid-Open No. 2-94040 to obtain a bonded disk having further excellent durability. It is also possible to install this in the fourth station IV of FIG. 1 of this embodiment and to carry out the operation continuously.

At the time of the above-mentioned adhesion, even when the adhesive 8 is spread and even when the space between the adhesive application loci remains unfilled, the adhesive 8 spread at other parts is exposed to the outside air. Since this portion is kept in a vacuum state in order to cut off communication with and, no bubble is formed.

The adhesive 8 can be applied in a similar manner by applying a plurality of nozzles 2 in a plurality of spirals or by moving a motor 7 for fixing the nozzles 2 and rotating the disk A. By applying the adhesive agent 8 in a spiral shape, the spread of the adhesive agent 8 can be uniformly diffused on the entire adhesive surface by vacuumizing the portion between the application loci.
The adhesive 8 is prevented from protruding from the outer peripheral surface of the disk and causing dripping.

FIG. 6 shows an adhesive application locus according to another embodiment of the present invention. In the previous embodiment, the nozzle 2 was continuously moved to apply the adhesive 8 on the spiral locus. Then, the adhesive 8 having a concentric circular locus is applied by intermittently moving, and the ejection of the adhesive 8 from the nozzle 2 is stopped at the beginning or the end of each concentric circle, and a part of the locus of each concentric circle is stopped. By providing the non-application portion 20 and allowing the air in the space portion between the concentric circles to be sucked out, the same effect as that of the previous embodiment can be obtained.

In each of the above-mentioned embodiments, instead of the hot-melt type adhesive, another adhesive, for example, in the case where a plurality of nozzles 2 are used to draw a plurality of spiral loci, a two-liquid mixed type epoxy system is used. An adhesive can be used, but the viscosity of the adhesive is preferably 5000 cps or more.

[0032]

As described above, according to the present invention, since air such as air bubbles does not remain between two bonded disks, not only the adhesive strength of the disks is greatly improved, It is possible to prevent moisture from invading the adhesive layer of the disc, causing moisture absorption of the disc member, corrosion of the aluminum reflective film, peeling, warping, etc. due to environmental changes and long-term use. ..

Further, unlike the case of applying the adhesive with a roll coater which has been conventionally performed, a brush stitch of the adhesive does not occur, so that it is possible to form a flat adhesive layer, which is adhered. In addition to preventing air from remaining in the layer, hard foreign matter mixed in the adhesive and damage to the information pits caused by the roll damaged by the foreign matter are also prevented.

The above-mentioned method and apparatus for manufacturing a laminated disk have the advantage that the above-mentioned laminated disk can be easily manufactured in large quantities.

[Brief description of drawings]

FIG. 1 is a plan view of the entire bonded disc manufacturing apparatus of one embodiment of the present invention.

FIG. 2 is a front view of the adhesive applying device.

FIG. 3 is a plan view of an adhesive application locus according to the above.

4 is a front view of the disk vacuum / pressure bonding apparatus of FIG. 1. FIG.

FIG. 5 is a plan view of another embodiment of the adhesive application locus.

[Explanation of symbols]

 A disk 2 nozzle 3 moving device 5 vacuum and pressure bonding device 7 motor 8 adhesive 13 upper vacuum tank 15 lower vacuum tank 16 vacuum pump

Claims (2)

[Claims] 1. The center of the disc is the portion between the adhesives which is not coated with the adhesive, such as a spiral, on at least one bonding surface of the two discs to which information is optically recorded and laminated. Side or the outer circumference side, a continuous locus is applied, the laminating surfaces of the two discs are overlapped, the air between the loci is evacuated, and then the two discs are pressure bonded. And a method for manufacturing an optical laminated disc, which comprises solidifying an adhesive. 2. The center of the disc is the portion between the adhesives which is not coated with the adhesive, such as a spiral, on at least one laminating surface of the two discs for optically recording and laminating information. Side, the coating means for applying a continuous trajectory to at least any one of the outer peripheral side, and two disks of which the adhesive is applied to the bonding surface of at least one of the disks in the above trajectory,
A superposition means for superposing the pasting surfaces, a vacuum evacuation means for evacuating the air between the loci, and a fixing means for solidifying the adhesive by press-bonding the two evacuated disks. An optical laminated disc manufacturing apparatus characterized by the above.