JP2000067477A - Method for laminating disks - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make improvable the positioning accuracy and to assure the flat ness of disks by sticking a tacky adhesive tape to the disk on one side or super posing two disks one on another and laminating these disk after sticking a tacky adhesive tape to the disk on one side, then processing the tacky adhesive tape in compliance with the shape of the disks. SOLUTION: When the disks and films are mutually superposed and laminated by sticking a tacky adhesive tape to the disk on one side or superposing two disks on each other and laminating these disk, then processing the tacky adhesive tape in compliance with the shape of the disks, the tacky adhesive tape is worked in compliance with the shape of the disks after the tacky adhesive tape is stuck and the disks are superposed on each other. The positioning accuracy is improved and the capturing of air bubbles and the film thickness unevenness of the tacky adhesive tape are suppressed, thereby, the flatness of the disks can be assured and the lamination assuring the reliability can be embodied even when information is read out across the tacky adhesive tape.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for laminating two disks or a disk and a film by laminating an adhesive tape.

[0002]

2. Description of the Related Art When manufacturing an optical disk or a magneto-optical disk or the like, when sticking an adhesive tape on two disks and superimposing them, an adhesive tape previously processed according to the shape of the disk is accurately positioned. A pasting method of pasting on a disk and superimposing the disc has been used.

[0003]

However, in the above-described conventional laminating method, uniform and good lamination is not always possible, such as poor positioning accuracy or local failure of peeling of the adhesive tape and the support depending on the processing state. There is a problem that alignment cannot be achieved. Especially when using an adhesive tape that failed to peel off locally from the support, it is easy to take in many air bubbles, and even after the subsequent pressing step or defoaming step by decompression or heating, many air bubbles Will remain. If the air bubble is large, the problem of flatness occurs immediately. If the air bubble is small, the air bubble expands due to a change in the temperature of the outside air, and the expansion lowers the flatness of the disk. Furthermore, the defoaming step by decompression or heating to remove the air bubbles generated in this way requires a long time to set a vacuum state or a high temperature state and a long time for setting in a container, thus reducing the productivity. There is also.

[0004] The influence of the flatness of an optical disk or a magneto-optical disk is caused by rotating the disk at a high speed when using the disk, irradiating the disk with a laser beam, and capturing the reflected light as a signal and reading it as a signal. Decreases, the surface vibration acceleration increases, and it becomes impossible to read as a reliable signal. Therefore, securing planarity in bonding is an important issue.

In the case where two discs or a disc and a film are superimposed and bonded to each other and information is read across the adhesive tape, minute air bubbles or film thickness of the adhesive tape which do not adversely affect the flatness are obtained. It has been found that unevenness also adversely affects the reliability of information reading.
One of the causes of such minute air bubbles and uneven thickness of the pressure-sensitive adhesive tape is that there are multiple steps such as a punching process in the production of the pressure-sensitive adhesive tape.

SUMMARY OF THE INVENTION The present invention solves the problems of the prior art and improves the positioning accuracy and suppresses the incorporation of air bubbles and the unevenness of the thickness of an adhesive tape when two discs or a disc and a film are overlapped. Accordingly, it is an object of the present invention to provide a method of bonding a disk which can secure the flatness of a disk and, in a recording medium, can realize bonding with reliability when reading information across an adhesive tape.

[0007]

According to a method of bonding disks of the present invention, in a method of bonding two disks together by using an adhesive tape, an adhesive tape is applied to one of the disks. After sticking, or after sticking the adhesive tape to one of the disks and then laminating and sticking the two disks together, the adhesive tape is processed according to the shape of the disk.

[0008] Alternatively, in the method of bonding a disk according to the present invention, the method of bonding a disk by laminating a disk and a film by using an adhesive tape may include bonding an adhesive tape to the disk or film. After overlapping and pasting,
The film and the adhesive tape are processed according to the shape of the disk.

That is, in the conventional laminating method in which an adhesive tape previously processed in accordance with the shape of a disc is accurately positioned, and is adhered to the disc and superimposed, the positioning accuracy is poor, or depending on the processing state, local positioning accuracy is low. And failure to peel the adhesive tape and the support,
Uniform and good bonding cannot always be achieved. Especially when using an adhesive tape that failed to peel off locally from the support, it is easy to take in many air bubbles, and even after the subsequent pressing step or defoaming step by decompression or heating, many air bubbles Will remain. If the bubble is large, the problem of flatness occurs immediately. If the bubble is small, the bubble expands due to a change in the temperature of the outside air, and the expansion deteriorates the flatness of the disk. Furthermore, in the defoaming step by decompression or heating to remove the air bubbles generated in this way, a long time is required for a vacuum state or a high temperature state, and a long time is required for setting in a container, which lowers productivity. When two discs or a disc and a film are superimposed on each other, and the information is read across the adhesive tape, minute bubbles that do not adversely affect the flatness and unevenness in the thickness of the adhesive tape are also considered. This adversely affects read reliability. One of the causes of such minute air bubbles and uneven thickness of the pressure-sensitive adhesive tape is that there are multiple steps such as a punching process in the production of the pressure-sensitive adhesive tape.

[0010] In the present invention, when two disks are superimposed on each other and then bonded together, an adhesive tape is pasted on one of the disks, or after the two disks are superimposed and bonded together. If the adhesive tape is processed according to the shape of the disc, and the disc and film are superimposed and pasted together, the adhesive tape is pasted on the disc or film, and then the film and adhesive tape are laminated. Process according to the shape of the disc. As a result, the positioning accuracy is improved, and the flatness of the disk can be ensured by suppressing the intake of air bubbles and the unevenness of the thickness of the adhesive tape. Further, even when information is read across the adhesive tape, it is possible to realize bonding with reliability.

As the substrate in the structure of the disk, for example, a polymer resin such as a polymethyl methacrylate resin, a polycarbonate resin, an epoxy resin, a polyolefin resin, or the like is expected to have a more favorable effect by applying the bonding method of the present invention. It is desirable because it can be done,
The present invention may be applied to a metal substrate such as an aluminum substrate, a glass substrate, a ceramics substrate such as a silicon substrate, or the like.
Similarly, in the configuration of the disk, the film may be, for example, a polyethylene terephthalate (PET) film,
Polyethylene naphthalate (PEN) film, polycarbonate film, polyether sulfone (PES)
A film, a polymer resin film such as a polyarylate film, and the like are preferable because more preferable effects can be expected by applying the bonding method of the present invention.

The thickness d1 of the film is 1 μm ≦ d1 ≦
It is preferably 0.6 mm. Films thinner than 1 μm are mechanically fragile or difficult to produce. For a film thicker than 0.6 mm, it is difficult to produce a uniform film, and it is difficult to control optical characteristics such as birefringence.

The thickness d2 of the entire disc after bonding is preferably 1.1 mm ≦ d2 ≦ 1.3 mm, and particularly preferably d2 = 1.2 mm. 1.
If it is thinner than 1 mm or thicker than 1.3 mm, there arises a problem that it becomes difficult to obtain compatibility with an optical disk or a magneto-optical disk which is currently widely used.

The bonding method of the present invention can be preferably used when manufacturing an optical disk or a magneto-optical disk. That is, it is preferable that the flatness of the bonded disks can be ensured, so that good recording / erasing / reproducing characteristics can be obtained in an optical disk or a magneto-optical disk.

In the bonding method of the present invention, the method of processing the adhesive tape or film according to the shape of the disk is not particularly limited. For example, a method of mechanically processing with a cutter or the like, a method of processing by heat, a method of chemical processing, There is a method of processing it.

[0016]

Examples 1 to 3 and Comparative Examples 1 to 3 In Example 1, two discs were superposed and bonded. After sticking an adhesive tape to one of the discs, the adhesive tape was formed into a disc shape. They were processed together, and then another disk was overlaid and bonded. as a result,
Good processing accuracy was obtained in a short processing time, and good flatness was obtained without air bubbles.

Embodiment 2 is a case in which a disc and a film are overlapped and bonded together. After sticking an adhesive tape to the disc, the films are overlapped and bonded, and then the adhesive tape and the film are matched to the shape of the disc. Processed. As a result, good flatness was obtained with a short processing time, with good positional accuracy, and without air bubbles.

Example 3 is a case in which a disc and a film are overlapped and bonded together. After sticking an adhesive tape on the film, the discs are stacked and bonded, and then the adhesive tape and the film are matched to the shape of the disc. Processed. As a result, good flatness was obtained with a short processing time, with good positional accuracy, and without air bubbles.

Comparative Example 1 is a case in which two disks are overlapped and bonded together. An adhesive tape previously processed in accordance with the shape of the disk is attached to one disk, and another disk is stacked. And stuck together. As a result, the adhesive tape may protrude from the disc due to poor positioning accuracy, or the adhesive tape and the support may fail locally to take in many air bubbles and not obtain sufficient flatness. Lamination could not be achieved.

Comparative Example 2 is a case in which a disc and a film are overlapped and bonded together. An adhesive tape previously processed according to the shape of the disk is attached to the disk, and the film previously processed according to the shape of the disk is applied. Laminated and stuck together. As a result, the adhesive tape may protrude from the disc due to poor positioning accuracy, or the adhesive tape and the support may fail locally to take in many air bubbles and not obtain sufficient flatness. Lamination could not be achieved.

Comparative Example 3 is a case in which a disc and a film are overlapped and stuck together. An adhesive tape previously processed according to the shape of the disc is stuck to the disc, the films are stuck together and the film is finally stuck. Was processed according to the shape of the disk. . As a result, the adhesive tape may protrude from the disc due to poor positioning accuracy, or the adhesive tape and the support may fail locally to take in many air bubbles and not obtain sufficient flatness. Lamination could not be achieved.

[0022]

As described above, according to the method of laminating disks according to the present invention, when two disks are superposed and bonded by using an adhesive tape, the adhesive tape is bonded to one disk. After, or after laminating two discs and laminating, by processing the adhesive tape according to the shape of the disc, or when laminating the disc and the film and laminating,
After sticking the adhesive tape on the disc or film and laminating, the film and the adhesive tape are processed according to the shape of the disc to improve positioning accuracy, capture air bubbles, and increase the thickness of the adhesive tape. By suppressing the unevenness, the flatness of the disk is ensured, the reliability of reading information across the adhesive tape is ensured, and good recording / erasing / reproducing characteristics can be obtained at high speed.

Claims (5)

[Claims] 1. A method of laminating two disks by laminating two disks together using an adhesive tape, wherein the adhesive tape is adhered to one of the disks or the adhesive tape is adhered to one of the disks. A method for laminating disks, comprising: after attaching, laminating and laminating two disks, processing the adhesive tape according to the shape of the disks. 2. A method of laminating a disk and a film by using an adhesive tape, wherein the adhesive tape is attached to a disk or a film, and the disk and the film are further laminated and laminated. And processing the adhesive tape according to the shape of the disk. 3. The method according to claim 2, wherein the thickness of the film is 1 μm to 0.6 mm. 4. Thickness of entire disc after bonding =
The method of laminating disks according to any one of claims 1 to 3, wherein the diameter is 1.1 mm to 1.3 mm. 5. The method according to claim 1, wherein the disk is an optical disk or a magneto-optical disk.