JPH03173954A - Production of optical disk - Google Patents

Abstract

PURPOSE:To produce a 2P resin film having high quality with simple operations by irradiating at least the outer peripheral positions of the 2P resin film with UV rays throttled to a beam shape and scanning the beam in a circumferential direction, thereby curing the 2P resin film. CONSTITUTION:The UV beam is scanned in the position of the outside diameter Ro and inside irradiater Ri when the positions 6, 7 are irradiated with the UV rays from above a transparent substrate 4 and a stamper 1 is rotated. If, therefore, the uncured 2P resin liquid diffuses and arrives at the scanning position of the UV beam, the liquid cures in this position and does not diffuse any more. The 2P resin is not cured in the part where the resin liquid does not arrive at the position of the outside diameter Ro and, therefore, the liquid diffuses in succession to the position of the outside diameter Ro and is irradiated with the UV beam, by which the resin is cured. As a result, the diffusion of the 2P resin liquid stops finally in the position of the outside diameter Ro over the entire periphery and the outer periphery of the 2P resin film is truly circular. The UV beam is scanned in the inside diameter position Ri on the inner peripheral side as well in exactly the same manner and, therefore, the 2P resin liquid is cured by the UV rays when the liquid arrives at the inside diameter position Ri. The truly circular inside diameter Ri is thus obtd.

Description

[Detailed Description of the Invention] [Summary] A method for manufacturing optical discs that is mass-produced by transferring a pattern formed on a stamper using a 2P resin, particularly a method for disciplining a 2P resin film before ultraviolet curing treatment. Regarding this, the purpose is to realize a manufacturing method in which the 2P resin film has a constant diameter when the 2P resin is diffused between the stamper and the glass substrate. After the resin liquid is sandwiched and diffused into a film, UV rays are irradiated to harden the 2P resin film to which the stamper pattern has been transferred, and then the stamper
In the method of peeling off from the stamper, when the 2P resin liquid is diffused into a film between the stamper and the transparent substrate, a beam is focused at least on the outer periphery and the inner periphery of the 2P resin film. By irradiating ultraviolet rays and relatively rotating the beam-shaped ultraviolet rays and the stamper, the beam-shaped ultraviolet rays are scanned on the same circumference, and the 2P resin liquid that has reached the scanning position is cured. do.

[Industrial application field]

The present invention allows the pattern formed on the stamper to be 2P (
Photo Polymer) resin (ultraviolet curing resin)
The present invention relates to a method for manufacturing optical discs that can be mass-produced by transferring using a method, and particularly to a method for forming a 2P resin film before ultraviolet curing treatment.

[Conventional technology]

FIG. 5 is a diagram showing a conventional method for forming a 2P resin film in order of steps. First, as shown in (2), a 2P resin liquid 3 is dropped by a dispenser 2 onto a stamper (master) 1 in which guide grooves have been formed in advance.

Next, as shown in ■, stack the glass substrates 4 and stamper 1.
The 2P resin liquid 3 is sandwiched between the two and diffused into a film as shown in (2). At this time, the guide groove of the stamper 1 is aligned with the 2P resin film 5.
transcribed into. With the 2P resin film 5 formed in this way, the entire surface of the glass substrate 4 is irradiated with ultraviolet rays to cure the glass substrate 4, and then the glass substrate 4 is peeled off from the stamper 1 as shown in (). An optical disc with guide grooves transferred to the film 5 is obtained.

[Problems to be Solved by the Invention] FIG. 6 is a plan view showing the state in which the 2P resin liquid is diffused in the step (■) in FIG. 5. 3 is a 2P resin solution dropped in a ring shape onto the stamper 1, and when a glass substrate 4 is placed on top of the stamper 1, the 2P resin solution is diffused by capillary action. The area 5 indicated by diagonal lines is in a diffused state, but the stamper
Since the surface of the glass substrate is not completely flattened, the spread of the 2P resin is not uniform, and the outer periphery has 5
As shown by a, a region protrudes from the glass substrate 4, or a region does not reach the outer periphery of the glass substrate 4, as shown by 5b.

A portion like 5a that protrudes from the outer periphery of the glass substrate 4 becomes a blank. Furthermore, in areas such as 5b that do not reach the outer J and YJ areas, the guide grooves cannot be transferred, resulting in an optical disc with missing guide grooves, which must be discarded as a defective product.

Also, on the inner circumferential side, 2P
The diameter of the inner circumference of the resin 1115 is not constant. However, since the inner peripheral part 8 of the optical disc normally serves as a clamping area when driving the optical disc and does not require a guide groove, there is no need to make the diameter of the 2P resin film the same on the outer peripheral side.

Therefore, a shield is provided around the outer periphery of the stamper 1 to prevent the spread of the 2P resin liquid, but the surface of the shield must be cleaned every time a transfer operation is performed, and at that time, the stamper pattern is contaminated, causing trouble in the next pattern transfer.

If a large amount of 2P resin liquid is dropped in order to eliminate the insufficient spread of the 2P resin liquid on the outer periphery, the generation of flakes is unavoidable, and the firmness must be removed after UV curing treatment, but at that time dust occurs.

The technical problem of the present invention is to focus on such problems and realize a manufacturing method in which the 2P resin film has a constant diameter when the 2P resin liquid is diffused between the stamper and the glass substrate. There is a particular thing.

(Means for Solving the Problems) FIG. 1 is a new diagram illustrating the basic principle of the method for manufacturing an optical disc according to the present invention, in which a 2P resin liquid is dropped onto a stamper 1, and a transparent substrate 4 is placed on top of the stamper 1. 5c is a 2P resin film in an uncured state.

6.7 is the ultraviolet beam, and the outer ultraviolet beam 6
is applied to the outer diameter position of the 2P resin film, and 11% of the inner ultraviolet beam 7 is applied to the inner diameter position of the 2P resin film. Then, the stamper 1 or the ultraviolet beam 6.7 is rotated around the center C of the stamper 1, and the stamper 1 or the ultraviolet beam 6.7 is rotated from above the glass substrate 4 at the outer and inner diameter positions of the 2P resin film.
Scanning the ultraviolet beam. 6g and 7g are guides for the ultraviolet beam.

Incidentally, the irradiation (1) of the ultraviolet beam 7 on the inner peripheral side may be omitted.

[Effect]

21d (a) and 21d (b) are plan views illustrating the operation of the present invention. Now, from above the transparent substrate 4, 6 in FIG.
When the ultraviolet beam is irradiated to the position 7 and the scrubber 1 is rotated, the ultraviolet beam is scanned at the positions of the outer diameter Ro and the inner diameter Ri. Therefore, the uncured 21] resin liquid 5C diffuses, and when it reaches the scanning position of the ultraviolet beam as shown in (a), it hardens at that position and does not diffuse any further. And, as shown by 5b, the outer diameter R.

Since the 2P resin has not yet been cured in the portion that has not reached the position, the resin continues to diffuse to the position of the outer diameter Ro, and is irradiated with the ultraviolet beam and cured. As a result, in the end, (
As shown in b), at the position of the outer diameter Ro over the entire circumference,
The diffusion of the 2P resin liquid stops, and the outer circumference of the 2P resin model becomes a perfect circle.

Similarly, on the inner circumferential side, the ultraviolet beam is scanned at the inner diameter position R4, so as shown in (a), the 2P resin liquid is at the inner diameter position 1? When it reaches i, it is cured by ultraviolet light, and finally (b
), the inner diameter Ri is the real cause.

〔Example〕

Next, how the method for manufacturing an optical disc according to 1 of the present invention is actually implemented will be explained using an example.

FIG. 3 is a diagram showing, in order of steps, an embodiment of the method for forming a 2+) resin film according to the present invention.

As shown in the figure, 21) resin 3 is dropped using a dispenser 2 onto a stamper (master) 1 on which guide grooves have been formed in advance. At this time, the 2P resin liquid is applied dropwise while rotating the stamper 1 in a ring shape.

Next, as shown in ■, stack the glass substrates 4 and stamper 1.
2P resin 3 is sandwiched between the two and diffused into a film as shown in (2). At this time, the light guides 6g and 7g are positioned at the outer diameter Ro and inner diameter Ri of the 2P resin film, and the beam diameter is 0,
In addition to irradiating the ultraviolet beam 6.7 with a diameter of about 5 mm,
Rotate stamper 1. As a result, the inner and outer peripheries of the glass substrate 4 are scanned with a beam in the circumferential direction at positions with a constant diameter.

As shown in theory I91 in Fig. 2, when the 2P resin liquid spreads to the outer diameter RO and inner diameter Ri, it is cured by the ultraviolet beam and the 2P resin liquid is
The outer diameter and inner diameter of the P resin film 5 become a perfect circle.

Moreover, as a result, all the guide grooves of the stamper 1 are transferred to the 2P resin film 5. With the 2P resin film 5 formed in this way, as shown in (■), the glass base + fi 4 is
After irradiating the entire surface of the 2P resin film 5 with ultraviolet rays and curing the entire surface of the 2P resin film 5 with UV rays, the glass substrate 4 is peeled off from the stamper 1 as shown in (2), and an optical disc with guide grooves transferred to the 2P resin film 5 is obtained. is obtained.

In this embodiment, the light guides 6g, 7g are fixed at the positions of the outer diameter Ro and the inner diameter Ri, but the light guides 6g, 7g may be rotated around the center C of the stamper 1. Alternatively, the stamper 1 and the light guides 6g, 7g may be rotated in opposite directions.

The irradiation angle of the ultraviolet beam 6.7 does not necessarily have to be perpendicular to the glass substrate 4. Further, since the inner circumferential side of the optical disc becomes the clamp area 8, there is no need for the inner circumference of the 2P resin film to be an accurate perfect circle, so it is not necessarily necessary to irradiate the inner circumferential side with the ultraviolet beam.

As described above, a 2P resin film can be formed into a perfect circle by curing with an ultraviolet beam on the inner and outer peripheries of the stamper 1. However, in order to spread the 2P resin liquid more evenly, it is necessary to The method of dropping the 2P resin is also relevant. That is, if the 2P resin liquid is simply dropped at one point on the stamper 1, it cannot be uniformly spread over the entire surface.

Therefore, in the present invention, when dropping the 2P resin liquid using the dispenser 2, as shown in FIG.
1, the 2P resin liquid is dropped in a ring shape. When a glass substrate is placed on such a ring-shaped 2P resin liquid 3, the 2P resin liquid spreads to the outer circumferential side and the inner circumferential side, so that it is uniformly diffused over the entire surface.

Further, the ring-shaped 2P resin liquid 3 is not applied exactly around the -turn, but is stopped at a position just before the -turn so that the application start point 31 and the application end 32 of the 2P resin liquid 3 are not connected.

The application start point 31 of the 2P resin liquid 3 swells like a snake's head, and there is an excess of 2P resin only at that position, but the interval is set so that the application start point 31 of the 2P resin liquid 3 and the application end 32 do not connect. If G is left open, when the glass substrate is placed and diffusion begins, the excess 2P resin liquid at the coating start point 31 will spread in the area of the gap G, as shown by the broken line. When connected to the coating end 32, the surface tension forms a ring of 2P resin liquid with a constant width, as shown by the chain line. As a result, the amount of the 2P resin liquid becomes uniform over the entire circumference, and the 2P resin liquid can be uniformly spread over the entire surface.

〔Effect of the invention〕

As described above, according to the present invention, when the 2P resin liquid is diffused into a film between the stamper and the transparent substrate, at least the outer peripheral position of the 2P resin film is irradiated with ultraviolet rays focused in a beam shape, A method is adopted in which the 2P resin liquid that reaches the scanning position is cured by scanning in the circumferential direction. Therefore, the 2P resin liquid hardens at the scanning position and cannot spread any further, making it possible to form a perfectly circular 2P resin film, which eliminates the occurrence of cracks and missing guide grooves as in conventional methods. There is no need to worry. Moreover, since there is no need to provide a shield to block the 2P resin liquid, the work is simple and there is no risk of quality deterioration.

[Brief Description of the Drawings] Fig. 1 is a cross-sectional view explaining the basic principle of the optical disc manufacturing method according to the present invention, Fig. 2 is a plan view explaining the operation of the method of the present invention, and Fig. 3 is a cross-sectional view explaining the basic principle of the method of manufacturing an optical disc according to the present invention. Figure 4 is a plan view showing the method of dropping the 2P resin liquid; Figure 5 is a side view showing the conventional method for manufacturing an optical disk in the order of steps; Figure 6 is a diagram showing the process in which diffusion is performed in the same method. FIG. 2 is a plan view showing a 2P resin film. In the figure, l is the stamper 3, the dropped 2P resin liquid, 4 is the transparent substrate (glass substrate), 5 is the cured 2P resin film, 5a is the 2P resin pad, 5b is the missing part of the 2P resin,
5c shows the 2P resin film before curing, 6 shows the ultraviolet beam at the outer circumferential position, and 7 shows the ultraviolet beam at the inner circumferential position.

Claims (1)

[Claims] After the 2P resin liquid is sandwiched between the stamper and the transparent substrate and diffused into a film, ultraviolet rays are irradiated to cure the 2P resin film with the stamper pattern transferred thereto. In the peeling method, when the 2P resin liquid (5c) is diffused into a film between the stamper (1) and the transparent substrate (4), at least the outer peripheral position of the outer peripheral position and the inner peripheral position of the 2P resin film is is irradiated with ultraviolet rays (6) focused in a beam shape, and the beam-shaped ultraviolet rays (6) and the stamper (1)
A method for manufacturing an optical disc, comprising: scanning a beam-like ultraviolet ray on the same circumference by rotating the 2P resin liquid (5c) relative to each other; and curing the 2P resin liquid (5c) that reaches the scanning position.