JPH0750536B2 - Method of copying information recording medium - Google Patents

Description

The present invention relates to a method for reproducing an information recording medium having a non-flexible substrate from a master medium on which information is recorded by forming irregularities on the surface. It is about.

[Outline of Invention]

According to the present invention, in the method for duplicating an information recording medium as described above, information is transferred from the master medium to the synthetic resin substrate by photopolymerization, and the information is further transferred from the synthetic resin substrate to the non-flexible substrate by photopolymerization. By doing so, it is possible to perform duplication accurately, in a short time, and with good controllability.

[Conventional technology]

In copying an information recording medium, particularly an optical information recording medium such as a disc, a metal stamper has been conventionally used regardless of a compression molding method, an injection molding method, a 2P method (photopolymerization method) or the like.

FIG. 2 shows an example of such a conventional method, and shows a method of duplicating an optical disk having a glass substrate by the 2P method.

In this conventional example, as shown in FIG. 2A, first, a glass master 13 in which information is recorded in a photoresist 12 on a glass master 11 is prepared. Next, as shown in FIG. 2B, an electroformed layer 14 made of nickel or the like is formed on the glass master 13, and then, as shown in FIG. 2C, the electroformed layer 14 is formed from the glass master 13.
Peel off.

Then, as shown in FIG. 2D, the ultraviolet curable resin 16 is supplied on the glass substrate 15, and the electroformed layer is further formed on the ultraviolet curable resin 16.
Close up 14 Then, in this state, ultraviolet rays are irradiated from the glass substrate 15 side to cure the ultraviolet curable resin 16.

After that, the electroformed layer 14 is peeled from the cured ultraviolet curable resin 16 and the glass substrate 15, and the ultraviolet curable resin as shown in FIG. 2E.
A reflective film 17 is applied to 16 and a protective film 18 is applied to the reflective film 17 and the glass substrate 15.

In this conventional example, the optical disc 19 is duplicated from the glass master 13 by the steps described above. Therefore, in this conventional example, the electroformed layer 14 is used as a stamper.

[Problems to be solved by the invention]

By the way, bubbles are generally mixed in the ultraviolet curable resin 16 at the stage of being supplied onto the glass substrate 15. If the ultraviolet curable resin 16 is cured with the bubbles left, the information recorded on the glass master 13 will not be transferred accurately.

Therefore, for example, pressure is applied to the ultraviolet curable resin 16 from both sides of the glass substrate 15 and the electroformed layer 14 by rollers (not shown), and the pressure is applied from one end of the glass substrate 15 and the electroformed layer 14 to the other end. It is conceivable that the bubbles are also moved from one end portion to the other end portion by relatively moving the rollers to push out the bubbles from the other end portion.

However, in the above-mentioned conventional example, since the electroformed layer 14 which is the stamper and the glass substrate 15 of the optical disk 19 are both inflexible, even if pressure is applied by the rollers, the pressure is partially applied to the ultraviolet curable resin 16. Is not applied, and a substantially uniform pressure is applied to the ultraviolet curable resin 16 over a considerably wide range. As a result, the bubbles do not move and are not pushed out.

Further, in the electroforming step, stress is generated when the metal is deposited, and this stress remains as an internal stress in the electroformed layer 14.
Therefore, when the electroformed layer 14 is peeled from the glass master 13, the electroformed layer 14 is distorted or deformed.

For this reason, the optical disc 19 duplicated by using such an electroformed layer 14 as a stamper is also distorted or deformed. That is, the information recorded on the glass master 13 is not accurately transferred to this optical disc 19.

Also, in the electroforming process, the metal does not always deposit flat,
Irregularities (not shown) are formed on the deposition surface 14a of the electroformed layer 14. For this reason, for example, when pressure is applied by the roller as described above, the signal surface 14b side also becomes uneven due to the unevenness on the deposition surface 14a side.

When the optical disc 19 is duplicated in this state, the information recorded on the glass master 13 is still not accurately transferred. Therefore, it is necessary to polish the deposition surface 14a, and it takes a long time to copy the optical disk 19.

Further, it takes about 2 to 3 hours to deposit the metal in the electroforming process, and the duplication of the optical disk 19 requires a correspondingly long time. Moreover, electroforming is a wet process and its controllability is poor.

[Means for solving problems]

The duplication method of the information recording medium according to the present invention includes a master medium 13
The surface of the first photo-curable resin 21 and the surface of the synthetic resin substrate 22.
And a step of irradiating the first photo-curable resin 21 with light to cure the first photo-curable resin 21 and to bond the first photo-curable resin 21 to the surface of the synthetic resin substrate 22. The step of peeling the synthetic resin substrate 22 to which the first photocurable resin 21 is adhered from the master medium 13, and the step of adhering to the surface of the non-flexible substrate 15 and the surface of the synthetic resin substrate 22. A step of contacting the first photo-curable resin 21 with the second photo-curable resin 16 interposed therebetween, and irradiating the second photo-curable resin 16 with light to cure the second photo-curable resin 16 and A step of adhering the non-flexible substrate 15 to the surface, and a step of adhering the non-flexible substrate 15 having the second photo-curable resin 16 adhered thereto to the synthetic resin substrate 22. And a step of peeling from the resin 21.

[Action]

In the method of duplicating the information recording medium according to the present invention, the synthetic resin substrate 22 obtained by curing and adhering the first photo-curable resin 21 is used as the stamper 23, and thus the stamper 23 has flexibility. .

Therefore, even if the non-flexible substrate 15 is used as the substrate of the information recording medium 19, the stamper 23 is bent to form a part of the second photocurable resin 16 between the stamper 23 and the non-flexible substrate 15. Bubbles can be extruded from the inside of the second photo-curable resin 16 by applying a positive pressure.

〔Example〕

An embodiment of the present invention applied to the duplication of an optical disc having a glass substrate will be described below with reference to FIG.

Also in this embodiment, the glass master 13 is first prepared in the same manner as the step shown in FIG. 2A in the above-mentioned conventional example.

Next, as shown in FIG. 1A, an ultraviolet curable resin 21 is supplied onto the photoresist 12, and a flat synthetic resin substrate 22 having a thickness of 3 to 10 mm is brought into close contact with the ultraviolet curable resin 21. As the synthetic resin substrate 22, a cast-molded substrate having no internal strain is used. Then, in this state, ultraviolet rays are irradiated from the synthetic resin substrate 22 side or the glass master 11 side to cure the ultraviolet curable resin 21 and adhere it to the synthetic resin substrate 22.

After that, the synthetic resin substrate 22 to which the ultraviolet curable resin 21 is adhered is peeled off from the glass master 13. At this time, the synthetic resin substrate 22
Since both and the UV curable resin 21 are made of synthetic resin, they are bent to bend the glass master 13 as shown in FIG. 1B.
Can be peeled off, and this peeling is easy.

Then, as shown in FIG. 1C, the ultraviolet curable resin 16 is supplied onto the glass substrate 15, and the cured ultraviolet curable resin 21 is brought into close contact with the ultraviolet curable resin 16. And in this state,
Ultraviolet rays are irradiated from the synthetic resin substrate 22 side or the glass substrate 15 side to cure the ultraviolet curing resin 16.

After that, the ultraviolet curable resin 21 and the synthetic resin substrate 22 are peeled off from the cured ultraviolet curable resin 16 and the glass substrate 15, and the optical disc 19 is completed in the same manner as the step shown in FIG. 2E in the above-mentioned conventional example. . Therefore, in this embodiment, the synthetic resin substrate 22 in which the ultraviolet curable resin 21 is cured and brought into close contact is used as the stamper 23.

When the stamper 23 is peeled off from the cured ultraviolet curable resin 16 and the glass substrate 15, the stamper 23 can be bent as in the step shown in FIG. 1B.

Further, in order to improve the reliability of the stamper 23 such as the increase of the surface hardness and the releasability from the ultraviolet curable resin 16, the signal surface 21a of the ultraviolet curable resin 21 is formed by vapor deposition or sputtering.
The signal surface 21a may be modified by depositing a metal film (not shown) or irradiating it with ultraviolet rays of short wavelength.
When the signal surface 21a is irradiated with short wavelength ultraviolet rays, the signal surface 2a
The crosslinking is promoted only near 1a, and the signal surface 21a is hardened.

Further, when the synthetic resin substrate 22 is brought into close contact with the ultraviolet curable resin 21 or the stamper 23 is brought into close contact with the ultraviolet curable resin 16, the synthetic resin substrate 22 and the stamper 23 are bent as shown in FIG. The bubbles in the ultraviolet curable resins 21 and 16 are extruded from the peripheral portion even if they are gradually brought into close contact with each other toward the peripheral portion.

Further, since the synthetic resin substrate 22 can be easily molded into an arbitrary shape such as a circle or a square in its plan view, it can be selected as a shape suitable for the duplication system.

Further, since the synthetic resin substrate 22 is a flat member cast-molded, no polishing is required, and since photopolymerization is performed in an extremely short time of about 10 seconds, duplication of the optical disk 19 can be performed in an extremely short time. Can be done.

In addition to the glass substrate 15, a non-flexible substrate such as a metal substrate may be used as the substrate for the optical disc 19.

〔The invention's effect〕

In the duplication method of the information recording medium according to the present invention, even if a non-flexible substrate is used as the substrate of the information recording medium, the bubbles can be extruded from the second photocurable resin, so that the duplication is accurately performed.

Further, since the information is transferred only by photopolymerization, there is no occurrence of internal stress and the like, so that the duplication can be performed accurately and the duplication can be performed in an extremely short time and with good controllability.

[Brief description of drawings]

FIG. 1 and FIG. 2 are side sectional views sequentially showing the steps of one embodiment and one conventional example of the present invention, respectively. In the reference numerals used in the drawings, 13 ... glass master 15 ... glass substrate 16,21 ... ultraviolet curable resin 19 ... optical disk 22 ... synthetic resin substrate 23 ... stamper.

Claims (1)

[Claims] 1. A method of reproducing an information recording medium having a non-flexible substrate from a master medium on which information is recorded by forming irregularities on the surface, the method comprising: A step of contacting the surface with a first photo-curing resin, and irradiating the first photo-curing resin with light to cure the first photo-curing resin and to the surface of the synthetic resin substrate. A step of adhering, a step of peeling the synthetic resin substrate to which the first photocurable resin is adhered from the master medium, and a step of adhering to the surface of the non-flexible substrate and the surface of the synthetic resin substrate. A step of bringing the first photo-curable resin into contact with the second photo-curable resin via a second photo-curable resin; and irradiating the second photo-curable resin with light to cure the second photo-curable resin and Adhering to the surface of the flexible substrate; The method of replicating the second photo-curable resin to adhere to said non-flexible said substrate adhering to said synthetic resin substrate first husband and a step of peeling of a photocurable resin people comprising information recording medium.