JPH052456B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to polishing the back surface of a metal stamper that can be used for manufacturing disc-shaped recording media.

Structure of conventional examples and their problems In recent years, as the development of information media such as optical disks and magnetic disks, which have higher density than conventional audio records, has progressed actively, it has become necessary to transfer recorded signals. High processing accuracy is required for metal stampers.

A conventional method for polishing the back surface of a metal stamper will be described below. As a method of holding a metal stamper, which is an object to be polished, on a disc-shaped metal plate, paraffin or other wax is used, and the signal surface of the metal stamper is fixed to the wax without protection using a press while heating. Thereafter, the back surface is polished by a polishing method or a wrapping method. This is a series of methods in which the wax is heated again after polishing is completed and the metal stamper is peeled off from the disk-shaped metal plate.

However, in the above method,
In order to fix the metal stamper to the disk-shaped metal plate that is the holder, a press device that can heat is required, and since the heating is performed at around 80°C, it is difficult to form a protective film on the signal surface of the metal stamper. It is. Further, after polishing, a device is required for cleaning paraffin and other waxes adhering to the signal surface of the metal stamper. It is desirable that the metal stamper be kept in a dry state at all times, but there has been a problem in that foreign matter may adhere to the signal surface or cause scratches during the cleaning process.

OBJECT OF THE INVENTION The object of the present invention is to simply keep the metal stamper in a dry state and to polish the back surface of a metal stamper, which enables high-precision back polishing processing without attaching foreign matter or scratching the signal surface of the metal stamper. The purpose is to provide a method.

Structure of the Invention The method for polishing the back surface of a metal stamper of the present invention includes disposing a peeling auxiliary sheet having a uniform film thickness and having a thickness larger than the outer diameter of a metal stamper as an object to be polished in the center of a disc-shaped metal plate, and A double-sided adhesive sheet is pasted on the side to cover the peeling auxiliary sheet, and a metal stamper with a protective coating on the signal side is fixed on the double-sided adhesive sheet with both sides of the signal corresponding to the double-sided adhesive sheet, and then a polishing method is applied. Alternatively, the method is characterized in that the back surface of the metal stamper is polished by a wrapping method, thereby eliminating the need for additional equipment for this process and preventing foreign matter from adhering to or scratching the signal surface of the metal stamper. This makes it possible to perform high-precision backside polishing without any problems.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a side view of a metal stamper fixed state in a method for polishing the back surface of a metal stamper according to an embodiment of the present invention. In FIG. 1, 1 is a metal stamper, 2 is a double-sided adhesive sheet, and 3 is a peeling auxiliary sheet. In this example, a paraffin sheet with a film thickness of about 50 μm was used. 4 is a disc-shaped metal plate, and 5 is a protective coat applied to the signal surface. A peeling auxiliary sheet 3 with a uniform thickness larger than the outer diameter of the metal stamper 1 is placed in the center of a disc-shaped metal plate 4, and double-sided adhesive is applied so that the entire surface of the disc-shaped metal plate 4 is covered with the peeling auxiliary sheet 3. sheet 2
Attach. Furthermore, a protective coat 5 is applied to the signal of the metal stamper 1, and the signal side of the metal stamper 1 is fixed on the double-sided adhesive sheet 2 with the peeling auxiliary sheet 3 in the center.

Thereafter, the metal stamper 1 fixed to the disk-shaped metal plate 4 is placed on a rotatable disk-shaped polishing disk of a polishing device (not shown) with its back side facing downward, and the disk-shaped metal plate is accessed from above by some method. 4, and the back surface of the metal stamper 1 is polished by the revolution and rotation motion between the disc-shaped polishing disk and the metal plate 4.

After polishing, the outer diameter end face of the peeling auxiliary sheet 3 is cut with a cutter or other blade, and the metal stamper 1 is separated from the disc-shaped metal plate 4. FIG. 2 shows the metal stamper 1 in a separated state. Since the protective coat 5, the double-sided adhesive sheet 2, and the release assisting sheet 3 are attached in this order to the metal stamper 1, the back surface polishing process is completed while the signal surface remains protected. Note that the protective coat 5 can be easily peeled off from the signal surface of the metal stamper after polishing. Further, a protective coat such as Retect can be used.

As described above, according to this embodiment, by using the double-sided adhesive sheet 2 and the peeling auxiliary sheet 3 to fix the metal stamper 1, it is possible to simplify the back polishing work and always protect the signal surface of the metal stamper 1. are doing. In addition, in the above embodiment, the release auxiliary sheet 3
A paraffin sheet with a diameter of around 50 μm was used, but the material is not limited to paraffin sheets.
Any film may be used as long as it has a uniform thickness and has the ability to be easily separated from the disc-shaped metal plate 4. For example, a fluorinated resin sheet can be used. or,
Although the film thickness was set to be around 50 μm, any thickness may be used as long as the film thickness is uniform. However, in practice it is 200 μm.
The following are good.

Effects of the Invention As is clear from the above explanation, since the present invention uses a double-sided adhesive sheet to fix the metal stamper to the disc-shaped metal holder, no additional equipment is required for polishing work, and no additional work is required. Can be simplified. Moreover, since the signal surface is always protected during and after work, it is possible to obtain the effect that there is no possibility of foreign matter adhering or scratching.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing a state in which a metal stamper is fixed to a disc-shaped metal plate in an embodiment of the present invention, and FIG. 2 is a sectional view showing a state in which the metal stamper is separated from the disc-shaped metal plate. 1...Metal stamper, 3...Peeling auxiliary sheet,
2... Double-sided adhesive sheet, 4... Disc-shaped metal plate, 5... Protective coat.

Claims (1)

[Scope of Claims] 1. A peeling auxiliary sheet with a uniform thickness and larger than the outer diameter of a metal stamper as an object to be polished is arranged at the center of a disc-shaped metal plate, and the peeling auxiliary sheet is placed on the surface of the disc-shaped metal plate. A metal stamper with a protective coating on the signal side is fixed onto the double-sided adhesive sheet with both sides of the signal corresponding to the double-sided adhesive sheet, and then the metal A metal stamper backside polishing method for polishing the backside of a stamper. 2. The method for polishing the back surface of a metal stamper according to claim 1, wherein the material of the peeling auxiliary sheet is a fluorinated resin or paraffin that can be easily peeled off from the disc-shaped metal plate.