JPH03137826A - Production of disk-shaped information recording substrate - Google Patents

Abstract

PURPOSE:To press-weld disk base materials with uniform adhesive strength by fixing upper and lower press-welding rolls to maintain a specified clearance between the rolls and applying a specified rolling force on the disk-shaped base materials. CONSTITUTION:The clearance between the rolls 11 and 12 is adjusted and the material W is fed between the rolls. The material is discharged by the rolling force and rotating force of the two rolls. The material W is a base material S for production formed by forming a recording layer 22 on one surface having a recess of a base material 21 consisting of polycarbonate, superposing a thin Al film 3 and a protective film 24 thereon and sticking these base materials to each other by an epoxy resin, etc. The feeding of the material W to a press is easy if a holder 31 is used. The holder 31 consists of a body 32 having the hole of the diameter larger than the diameter of the material W at the center and a freely openable/closable cap 34 consisting of a film. While the material W passes through the rolls, the material is ironed and the misregistration between the superposed base materials is effectively prevented. The material W is press-welded with the adhesive strength uniform over the entire surface and the recording substrate which is free from warpage, infiltration of air, etc., is formed at a good yield.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a method for manufacturing a disk-shaped information recording substrate, and more specifically, the present invention relates to a method for manufacturing a disk-shaped information recording substrate, and more specifically, in a pressing process of press-bonding a plurality of disk-shaped substrates, a roll press machine is operated under specific conditions. The present invention relates to a method for manufacturing a disk-shaped information recording substrate, which is used in the industry and has a high yield with almost no defective products.

(Prior Art) In recent years, disk-shaped information recording substrates such as optical disks have been put into practical use due to their extremely large recording capacity and the need for paperless technology.

Disk-shaped information recording substrates are used to protect the recording layer that governs writing and reading of information, and so on. It is produced by bonding a base material and a disc-shaped information recording base material on which no recording layer is formed in advance using an adhesive, using a pressure bonding means.

Conventionally, a hydraulic press machine such as a hydraulic press machine or a pneumatic press machine has been used as the compression bonding means.

FIG. 5 is a front view of a hydraulic press machine used in the conventional crimping method.

In the figure, a hydraulic press machine 51 includes a steel movable press 52 having a flat and circular press surface, a support member 53 that supports the movable press 52 in a vertically movable manner, and a flat and circular press surface. It consists of a fixed press 54 made of steel, a fixing member 55 that fixes and supports the fixed press 54, and the like.

The movable press 52 and the fixed press 54 are arranged with their press surfaces facing each other so that the axes of their press shafts coincide with each other, and the press surfaces of both presses 52 and 54 have
An elastic sheet 56 made of silicone rubber is bonded together so that a uniform rolling blade is applied to the material W to be pressed.

In the hydraulic press machine 51 configured as described above, the press-bonded material W, which is made of a plurality of disc-shaped base materials stacked together with an adhesive, produced in the previous step, is placed in the center of the press surface of the fixed press 54, When the movable press 52 is lowered by driving an attached hydraulic cylinder (not shown) and pressed for a predetermined time while applying a predetermined pressure to the material to be bonded W, the adhesive action of the adhesive is strongly developed, and each base material are crimped and integrated.

In addition, the air press method uses a different power medium.
This method is common to the above-mentioned hydraulic press method in that it uses fluid pressure.

The above is an overview of the conventional method for manufacturing a disk-shaped information recording substrate.

[Problems to be Solved by the Invention] However, in the above-mentioned conventional manufacturing method using a fluid pressure press machine, defective products with defects such as warping, tilting, splitting, and air inclusion, which make it difficult to read out well, are frequently produced. There was a problem.

Therefore, in order to find the cause, a hydraulic press machine 51 shown in Fig. 5 was used to increase the disc pressure to 10 kg/cf.
The state of pressure distribution when fl was applied for 5 seconds was investigated by pressing a pressure measurement film (manufactured by Fuji Photo Film Co., Ltd., trade name: "Prescale Ultra Low Pressure").

FIG. 6 shows the pressure measurement film at that time, and in the figure, the shade of color represents the magnitude of the pressure applied to the relevant location.

As is clear from the figure, there are significant shadings, indicating that the pressure is not uniformly applied to the material to be bonded.

Next, let's consider why the pressure is not applied uniformly.

Returning to FIG. 5, when the cylinder device is driven, the press shaft 5-2a of the movable press 52 is supported by the hole 53a of the support member 53 and moves up and down. In order to enable this vertical movement, the press shaft 52a and the hole 53a are
A predetermined gap is provided between the two.

For this reason, no matter how the upper and lower presses 52, 54 are arranged so that the axes of their press shafts coincide with each other, when viewed microscopically, there will be some misalignment between the two wheel centers. Although such deviation is minute, it cannot be ignored in the press-bonding of information recording substrates, which requires precision on the order of microns.

This is the reason why conventional methods frequently produce defective products with warpage, tilting, etc.

Furthermore, in the conventional method, there is a risk that air may be mixed between the base materials during crimping.

Furthermore, it is difficult to incorporate into a continuous production line, so
It does not meet the modern trends of labor-saving and automation of manufacturing lines, and there are also problems in terms of production efficiency.

The present invention has been made in view of the above circumstances, and its purpose is to provide a method for manufacturing a disk-shaped information recording substrate that has a high yield and can be easily incorporated into a continuous production line. be.

[Means for Solving the Problems] A method for manufacturing an information recording substrate according to the present invention to achieve the above object includes a method of manufacturing a plurality of disc-shaped base materials stacked one on top of the other with an adhesive interposed between each base material, In manufacturing a disk-shaped information recording substrate by pressing with a pressing means, a roll press machine equipped with at least a pair of pressing rolls arranged in parallel is used as the pressing means, and the clearance between the pressing rolls is set to a predetermined size. The main point is to pass the plurality of disk-shaped base materials between the pressure bonding rolls and pressure bond them.

[Function] In the method of the present invention, when the disk-shaped substrates are fed to a roll press machine, the disk-shaped substrates are sequentially squeezed and pressed while releasing air between the substrates.

At that time, the upper and lower pressure bonding rolls were fixed to maintain a constant clearance between the rolls, and a constant rolling blade was applied to the disc-shaped base material, so that the disc-shaped base material was crimped with uniform adhesive strength in the transport direction. be done.

Furthermore, since the upper and lower pressure rolls are disposed in parallel to perform pressure bonding, the material to be pressure bonded is pressure bonded with uniform adhesive strength even in the direction orthogonal to the transport direction.

[Examples] Hereinafter, the present invention will be explained based on Examples, but the present invention is not limited to the following Examples, and can be modified as appropriate without changing the gist thereof.

FIG. 1 shows an example of a roll press machine as a crimping means for carrying out the method for manufacturing a disk-shaped information recording substrate according to the present invention. When pressing a thick disc-shaped base material, the press usually consists of a pair of upper and lower pressing rolls 11.12 arranged in parallel with a distance of about 2.2 to 2°65 Ill111, a drive motor (not shown), and the like.

The crimping rolls 11 and 12 are configured so that the roll spacing (clearance) can be adjusted according to the thickness of the material W to be crimped, the desired rolling blade, etc., and each of the crimping rolls has a coating on its circumferential surface. An elastic member made of silicone rubber or the like with a thickness of approximately 1 to 5 m is stretched so that the pressing blade is applied uniformly to the crimping material W. Note that the bodies of the pressure rolls 11 and 12 are made of a hard material such as steel.

Both ends of each roll shaft 11a, 12a of the pressure roll 11.12 are supported by support means (not shown), and are also connected to a drive motor, so that the material fed from the left side in the figure is driven by the drive motor. It is configured so that the pressure bonding material W can be discharged to the right in the figure while being pressure bonded.

In addition, the roll length of each pressure roll 11.12 is as long as the roll shafts 11a, 12a have sufficient thickness, strength, etc.
Although not particularly limited, care must be taken because unnecessarily long rolls may cause deflection and make it impossible to roll down uniformly.

Using the roll press machine 1 as described above, the information recording substrate C
To manufacture D, first, the clearance of the crimping rolls 11 and 12 is adjusted so that an appropriate reduction blade is applied to the material W to be crimped, and then the motor is driven to rotate both rolls, and a roll press machine is used. 1 into a state where it can be crimped.

Next, the material W to be crimped is re-pressed from the left side in the figure by the re-crimping roll 11.
．． 12, and is discharged toward the right in the figure while being crimped by the rolling blade and rotational force of the re-crimping roll.

FIG. 2 is a cross-sectional view showing an example of a press-bonded material W, in which a recording layer 22 with a thickness of 1,000 to 3,000 layers is formed on one side of a base material 21 made of polycarbonate or the like having a concave portion. It is formed using a conventionally known method such as compression molding, injection molding, 2P method, etc., and then a thin aluminum film 23 as a light reflecting plate is formed by sputtering or the like, and a protective layer with a thickness of about 3 to 20 μm is further applied thereon. Two sheets with the film 24 formed thereon are bonded together with each protective film 24 coated with various adhesives such as epoxy, ultraviolet curing, acrylic, etc. to a thickness of 2.
This is a base material S for manufacturing a 4mi information recording board.

Note that the feeding to the above-mentioned clearance may be performed continuously using a transport roll, a conveyor, or the like.

Alternatively, an appropriate holder may be used.

FIG. 3 shows an example of a holder used in such a case. In the figure, the holder 31 includes a main body 32 having a through hole in the center with a diameter slightly larger than the diameter of the material W to be pressed, a soft film 33 that closes the bottom of the through hole, and an upper part of the through hole that can be opened and closed. It is made of a flexible film 34 that can be closed freely, and is configured so that the press-bonded material W can be accommodated in the formed hole. The main body 32 is formed to be slightly thinner than the material W to be pressed so that the material W to be pressed can be pressed.

By using such a holder, it is possible to effectively prevent the press-bonded material W from being squeezed while passing between the rolls and causing misalignment between the base materials that have been aligned and stacked in advance. At the same time, it becomes easy to feed the press-bonded material W to the roll press IT.

Further, the holder 31 may be formed into a band shape, and a plurality of press-bonded material storage sections may be provided so that a plurality of press-bond materials W can be held at regular intervals, thereby automating the manufacturing line.

A final product is completed by attaching an appropriate label to the information recording substrate CD obtained as described above.

Figure 4 shows a film in which the aforementioned pressure measurement film (manufactured by Fuji Photo Film Co., Ltd., trade name ``Prescale for ultra-low pressure'') is superimposed on a disk-shaped base material with a thickness of 2.46 mm. Diameter 13 with rubber bonded to the press surface
This is a pressure measurement film after crimping when the unpressed clearance between the 0 m re-crimping rolls 1112 is set to 2.25 m* and crimping is carried out at a line speed of 5 m/min.

As is clear from the figure, uniform coloring appears and it can be seen that pressure is applied uniformly to the entire surface of the disk.

In the above embodiment, a case has been described in which a roll press machine equipped with a pair of pressure rolls is used, but the present invention is not limited to such a case, and it is also possible to use a plurality of pairs of pressure rolls as necessary.

In addition, a model clearance adjustment member that can adjust the clearance by advancing and retreating, for example, is inserted between the re-compression rolls, and both ends of one roll shaft are biased from the opposite direction by biasing means such as fluid pressure or a spring. By constantly applying force, the roll press machine may be prevented from being damaged.

Furthermore, if a thermosetting adhesive is used as the adhesive, a heater may be attached to one of the pressure rolls.

[Effects of the Invention] As explained above in detail, according to the method of the present invention, the entire surface of the material to be pressed can be crimped with uniform adhesive strength, so a disk with almost no warping, tilting, air inclusion, etc. can be produced. The present invention has excellent and unique effects, such as being able to manufacture a shaped information recording substrate with high yield and easily automating a manufacturing line.

[Brief explanation of the drawing]

Fig. 1 is a front view of a roll press machine used in carrying out the method of the present invention, Fig. 2 is a sectional view of the material to be bonded, Fig. 3 is a perspective view of a holder suitable for use in the method of the present invention, and Fig. 4. is a plan view of a pressure measurement film showing the pressure distribution on the material to be crimped when using a roll press machine, Figure 5 is a front view of a hydraulic press machine used in the conventional crimping method, and Figure 6 is a diagram showing a hydraulic press machine. It is a top view of the pressure measurement film which shows the pressure distribution applied to the material to be pressure-bonded when it is used. CD・-Disc-shaped information recording substrate W-Pressure bonded material (disc-shaped base material)

Claims (1)

[Claims] 1. In manufacturing a disk-shaped information recording substrate by pressing a plurality of disc-shaped base materials stacked one on top of the other with an adhesive interposed between each base material using a compression-bonding means, as the compression-bonding means: Using a roll press machine equipped with at least a pair of pressure rolls arranged in parallel, and setting a clearance between the pressure rolls to a predetermined size, the plurality of disc-shaped substrates are passed between the pressure rolls. 1. A method for manufacturing a disk-shaped information recording substrate, characterized in that the substrate is pressure-bonded using a pressure-bonding method. 2. The method of manufacturing a disk-shaped information recording substrate according to claim 1, wherein the pressure roll is provided with an elastic member on its circumferential surface.