JP2533182B2 - Optical disc manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Overview] Regarding a method of attaching a metal hub to a double-sided optical disk, a disk portion to which a convex hub or a concave hub adheres for the purpose of improving workability such as shortening working time. The step of making a veneer disc not coated with a recording film on the surface of, and an ultraviolet curing resin is applied between one veneer disc and the convex hub, and the veneer disc and the convex hub are attached. After bonding and centering, irradiating ultraviolet rays from the single plate disk side to cure and fix the ultraviolet curing resin, and similarly, apply the ultraviolet curing resin between the other single plate disk and the concave hub. Then, after adhering and centering the single plate disc and the concave hub, ultraviolet rays are irradiated from the single plate disc side to cure and fix the ultraviolet curable resin, and then, the two single plate discs. of An adhesive is applied, characterized by comprising contains a step of fixing by hardening the adhesive is fitted with said convex hub and concave hub.

[Industrial applications]

The present invention relates to a method for manufacturing an optical disk, and more particularly to a method for mounting a metal hub on a double-sided optical disk.

Optical disks are regarded as important as storage devices for computers, and the present invention relates to a simple method for forming the optical disks.

[Conventional technology]

2 (a) and 2 (b) are views showing a double-sided optical disc,
The figure (a) is a cross-sectional view, the figure (b) is a plan view, and a partially enlarged view is additionally shown in FIG. 2 (a). In these figures, 1 and 2 are single disk (diameter 130mm or 200mm,
Thickness 1.2mm), 3 is epoxy resin adhesive, 4 is a convex hub (outer diameter 70mmφ), 5 is a concave hub, 6 is a glass substrate (see the enlarged view below), 7 is a guide groove (pre-groove) 2P (photopolymer) film (thickness about 30 μm) provided with, 8 is a recording film also formed on the glass substrate surface (thickness about 300 nm including a protective film)
The single plate discs 1 and 2 are composed of the 2P film 7 and the recording film 8 laminated on the surface of the glass substrate 6, and the double-sided optical disc has two 2P films having a guide groove and the recording film inside. This is a structure in which a single disk is bonded.

Furthermore, glass or transparent synthetic resin plate (PMMA, PC, etc.) is used for this disc substrate, and its thickness is 1.2.
Since it is as thin as about mm, glass substrates are often used for those requiring flatness. However, the glass substrate has a drawback that it is fragile, and for this reason, a metallic hub is attached to the inner diameter side surface portion in contact with the rotating shaft.

3 (a) and 3 (b) show a plan view and a sectional view of the hub. FIG. 3 (a) shows a convex hub 4 and FIG. 3 (b) shows a concave hub 5, for example, a hub. The outer diameter is about 70 mmφ, the concave hub can be fitted to the convex hub with high precision, and the material is made of metal such as stainless steel.

By the way, in order to accurately detect the memory (stored signal) stored in such an optical disc by the optical head, the guide groove of the optical disc and the hub must be aligned so as not to be eccentric.

A conventional method of mounting an optical disk hub for this purpose is shown in FIGS. 4 (a) and 4 (b). To explain the outline, first, as shown in FIG. 4 (a), epoxy resin is applied to one surface of the single plate disk 1 and is bonded to the other surface of the single disk 2, and a jig (not shown) is used. ) Is used for centering and alignment is performed while observing the quality, and then the epoxy resin adhesive 3 is solidified over a period of time. Next, as shown in FIG. 4 (b), the adhesive disks 1 and 2 and the convex hub 4 are placed on a turntable to center the bonded disks 1 and 2 and the convex hub 4. In between, epoxy resin adhesive 3
Then, observe the deviation with a microscope while rotating the turntable, correct the deviation, and perform centering. Then, if aligned, the ultraviolet curable resin 9 is applied to an appropriate position between the disk and the convex hub, and then the ultraviolet curable resin 9 of ultraviolet rays is applied.
It irradiates and solidifies and temporarily fixes. Then, the epoxy resin adhesive 3 is solidified over a long period of time to fix the disk and the hub. Further, the concave hub 5 is coated with the epoxy resin adhesive 3 and fitted to the convex hub 4, and similarly solidified and fixed over time. The above is the conventional optical disc
This is the method of attaching the hub.

[Problems to be Solved by the Invention]

However, in such a conventional optical disc hub mounting method, the epoxy disc adhesive 3 is applied after the adhesive discs 1 and 2 on the turntable and the convex hub 4 are coated with the epoxy resin adhesive 3 and then centered. Since it takes a long time to cure, it is a method of applying the ultraviolet curable resin 9 to temporarily fix it, and solidifying the epoxy resin over time. Therefore, the process is complicated and the curing time is long. However, there are some drawbacks such as poor workability.

The present invention proposes a manufacturing method capable of improving workability by reducing such drawbacks and shortening work time.

[Means for solving the problem]

The problem is, as shown in the embodiment of FIG. 1, a step of producing single-plate disks 11 and 12 in which the recording film 8 is not coated on the surface of the disk portion to which the convex hub or the concave hub is in close contact. An ultraviolet curable resin 19 is applied between one of the single plate disks 11 and the convex hub 4, the single plate disk and the convex hub are bonded and centered, and then ultraviolet rays are irradiated from the single plate disk side. Then, the step of hardening and fixing the ultraviolet curable resin is performed. Similarly, the ultraviolet curable resin 19 is applied between the other single plate disk 12 and the concave hub 5 to bond the single plate disk and the concave hub. And centering, then irradiating ultraviolet rays from the side of the single plate disk to cure and fix the ultraviolet curable resin, and then apply the adhesive 3 between the two single plate disks 11 and 12, The convex hub and the concave hub are fitted to each other and the adhesive is hardened and fixed. It is by go-between solution to the production method that includes and that process.

[Work]

That is, according to the present invention, a single plate disk not covered with a recording film is formed on the surface of the disk portion shielded by the hub portion, and one of the single plate disks and the convex hub is centered by applying an ultraviolet curing resin. After that, ultraviolet rays are irradiated from the single plate disk side to cure and fix the ultraviolet curable resin. Similarly, the other single plate disk and the concave hub are hardened and fixed with the UV curable resin, and then the two single plate disks are fitted with the convex hub and the concave hub to cure the adhesive between the disks. Fix it.

By doing so, the disk and the hub are bonded together by a rapidly curable ultraviolet-curing resin, which shortens the working time and simplifies the process since temporary fixing is not required. In addition, in such an attaching method, the centering step by the microscopic observation is the same as the conventional one and is performed twice.

〔Example〕

Hereinafter, embodiments will be described in detail with reference to the drawings.

1 (a) to (d) are optical discs according to the present invention.
It is a figure which shows the attachment method of a hub. To explain step by step, see FIG. 1 (a); first, the single plate disks 11 and 12 are prepared by a known method, which is on a glass substrate 6 having a diameter of 200 mmφ as shown in a partially enlarged view. A guide groove (pre-group) is formed on the 2P film 7 coated on the substrate with a stamper, and a recording film (including a protective film) 8 is deposited thereon by a sputtering method. At this time, a mask (not shown) is formed on the surface of the disk portion shielded by the hub so that the recording film 8 does not adhere (when the hub outer diameter is 70 mmφ, a diameter of about 80 mmφ is masked). That portion is not covered with the recording film 8 (see a partially enlarged view). Forming an uncoated portion of the recording film on the disc surface is one of the differences relating to the present invention.
Since this non-covered portion is a portion shielded by the hub, there is no problem even if the recording film is not coated.

See FIG. 1 (b);
After making 2, the ultraviolet curable resin 19 is applied between one of the single plate disks 11 and the convex hub 4 to form a single disk.
11 and the convex hub 4 are placed on a turntable for centering and observed with a microscope while rotating to correct misalignment and centering, and if aligned, ultraviolet rays are cured from the single plate disk 11 side by an ultraviolet curing resin. Irradiate 19 and fix. At this time, the single plate disk 11 has a transparent glass substrate and a transparent 2P film and is transparent to ultraviolet rays, and the adhesive film between the single plate disk 11 and the convex hub 4 is not covered with the recording film. Ultraviolet rays that pass through 11 irradiate the ultraviolet curing resin 19 and cure it.

See FIG. 1 (c); then similarly the other single disk
An ultraviolet curable resin 19 is applied between the concave hub 12 and the concave hub 5, centered in the same manner, and if aligned, the ultraviolet curable resin 19 is irradiated with ultraviolet rays from the single plate disk 12 side and fixed.

1 (d); Finally, the epoxy resin adhesive 3 is applied between the veneer disk 11 with the convex hub 4 aligned and fixed and the veneer disk 12 with the concave hub 5 aligned and fixed. hand,
The convex hub 4 and the large hub 5 are fitted together and left to stand, and the epoxy resin is solidified over time.

The above is the mounting method according to the present invention, but according to such a forming method, temporary fixing of the hub is not necessary, and it becomes simple. To fix the disk and the hub, the ultraviolet curable resin is irradiated with ultraviolet rays. The working time is shortened because of the rapid solidification. Moreover, the centering processing by the microscope observation is performed twice, that is, the centering of the convex hub / single plate disk and the centering of the recessed hub / single plate disk. This is no different from the two times of centering, and therefore the workability of mounting is significantly improved.

〔The invention's effect〕

As is clear from the above description, according to the present invention, the workability of mounting the optical disk hub is improved, the processing throughput is improved, and the cost of the optical disk is greatly reduced.

[Brief description of drawings]

FIG. 1 is a diagram showing a method for mounting an optical disc hub according to the present invention, FIG. 2 is a diagram showing a double-sided optical disc, FIG. 3 is a plan view and a sectional view of the hub, and FIG. 4 is a diagram showing a conventional optical disc hub. It is a figure which shows the attachment method. In the figure, 1,2,11,12 are single plate disks, 3 is an epoxy resin adhesive, 4 is a convex hub, 5 is a concave hub, 6 is a glass substrate, 7 is a 2P film, 8 is a recording film, 9, Reference numeral 19 indicates an ultraviolet curable resin.

Claims (1)

(57) [Claims] 1. A step of producing a single plate disk not covered with a recording film on a surface of a disk portion to which a convex hub or a concave hub is in close contact, and an ultraviolet ray between one of the single disk and the convex hub. A step of applying a curing resin, adhering the center of the veneer disk and the convex hub, and then irradiating ultraviolet rays from the side of the veneer disk to cure and fix the UV curable resin; UV coating resin is applied between the single plate disc and the concave hub, and the single plate disc and the concave hub are bonded and centered, and then the ultraviolet curing resin is irradiated with ultraviolet rays from the single plate side. A step of curing and fixing, and a step of applying an adhesive between the two veneer disks and fitting the convex hub and the concave hub to cure and fix the adhesive. Optical disc characterized by being included Manufacturing method.