JPH05109122A - Optical master disk and production thereof and production of drum type stamper - Google Patents

Abstract

PURPOSE:To electrocast the high-quality drum type stamper itself by easily producing the optical master disk formed with plural rugged patterns corresponding to the duplicating of plural optical disks and rounding the optical master disk to a cylindrical shape by disposing the surfaces formed with the rugged patterns on the inner side. CONSTITUTION:For example, a UV curing type resin is applied on a flexible substrate having flexibility and a stamper 10 is compression bonded thereto. The compression bonded part is irradiated with UV rays 11 to cure the UV curing type resin. The sheet-shaped master disk 8a having plural master recording parts 9a formed with the rugged patterns is produced by iterating such stage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk and a method for manufacturing the same, and more particularly, to an optical disk master for mass-producing an optical disk on which various information signals are recorded in advance, a method for manufacturing the same, and a flexible optical disk duplication process. The present invention relates to a method for manufacturing a drum stamper used in.

[0002]

2. Description of the Related Art The manufacturing process of optical discs of read-only type, write-once type, rewritable type, etc. mainly consists of a master disc manufacturing process for master recording various information signals such as music / video information and tracking information, and a master disc. A stamper is manufactured from the master disk, and the master record made on the master disk is copied using the stamper.

The conventional master disc manufacturing process is as follows. First, as shown in FIG. 10A, a photoresist 2 is applied to a flat glass substrate 1. Next, FIG.
As shown in (b), the photoresist 2 is exposed by using the laser beam 7 whose intensity is modulated by the information signal, and so-called cutting is performed. When the cut photoresist 2 is developed, a master having a desired resist pattern 2a is obtained as shown in FIG. 10 (c).

To make a stamper from a master, the process shown in FIG.
As shown in (d), the nickel conductive film 3 is formed on the resist pattern 2a by means such as sputtering or vapor deposition.
To form. Further, as shown in FIG. 10E, electroforming treatment is performed to form a nickel electroformed film 5 on the conductive film 3. Finally, as shown in FIG. 10 (f), the stamper 6 is obtained by peeling the electroformed film 5 from the master.
If necessary, a mother stamper may be produced from the electroformed film 5, and the mother stamper may be similarly electroformed to obtain the stamper 6.

In addition to the above-mentioned manufacturing method, there is also a method of manufacturing a master by directly cutting an uneven pattern on a glass substrate by means of sputter etching, ion etching, plasma etching or the like.

Next, in order to manufacture a flexible optical disk using a film sheet which can be wound into a roll as a substrate, a drum type stamper having a stamper on a cylindrical surface is usually used. To produce this drum-type stamper, as disclosed in Japanese Patent Publication No. 63-31847, the thickness of the electroformed film 5 formed in the electroforming process corresponding to FIG. Set to 80 μm. The thus obtained sheet-shaped stamper 6 was peeled off from the master and was attached to the cylinder with an adhesive or a double-sided tape to produce a drum-type stamper.

[0007]

However, in the above-mentioned conventional method for manufacturing an optical disk master, if a plurality of masters are manufactured on a common substrate in order to duplicate a plurality of optical disks at once, one master disk is manufactured. The process needs to be repeated many times. For example, in Japanese Unexamined Patent Publication No. 61-214160, a substrate coated with a photoresist is repeatedly exposed and developed by laser light as many times as there are masters. Further, even in the method of producing a master by directly cutting the concavo-convex pattern on the glass substrate, the cutting process must be repeated many times. As a result, there is a problem in that the production yield of the master is deteriorated and the cost is increased.

Further, in the above-mentioned conventional method for manufacturing a drum type stamper, a very thin stamper 6 having a thickness of 20 to 80 μm is used.
Since bubbles and dust easily enter between the stamper 6 and the cylinder when it is attached to the cylinder, there is a problem in that the stamper 6 and the cylinder may be poorly adhered or separated, or may be deformed such as wrinkles. is doing. Further, since the stamper 6 is attached after being peeled off from the master, there is a problem that there is a high risk of damaging the signal surface.

An object of the present invention is to provide a method of manufacturing a plurality of masters on a common substrate in a simple process and an optical disk master manufactured by the method, and by using the optical disk master, peeling and It is an object of the present invention to provide a method for manufacturing a high-quality drum stamper that does not deform.

[0010]

In order to solve the above problems, an optical disk master according to the invention of claim 1 corresponds to a desired information signal (for example, a music signal, a video signal, or a tracking information signal). In an optical disc master used for duplication of an optical disc on which an uneven pattern is formed in advance, a flexible substrate (for example, a plastic substrate) having flexibility, and a resin layer having a plurality of the uneven patterns corresponding to duplication of a plurality of optical discs. (For example, an ultraviolet curable resin layer or a thermosetting resin layer).

In order to solve the above-mentioned problems, the method for manufacturing an optical disk master according to the invention of claim 2 forms an uneven pattern corresponding to the above-mentioned information signal based on a desired information signal recorded in advance on the optical disk. A first step of producing a first optical disc master having the second step, a second step of producing a stamper having an inverted concavo-convex pattern in which the concavo-convex shape is the reverse of the concavo-convex pattern based on the first optical disc master; A third step of forming a thermosetting or ultraviolet curable resin layer, press-bonding the stamper to one area of the resin layer, curing the stamper press-bonding portion, and transferring the concavo-convex pattern; A fourth step of producing a second optical disk master having a plurality of the concavo-convex patterns formed by repeating the third step over the entire area. It is.

In order to solve the above-mentioned problems, a method for manufacturing a drum stamper according to a third aspect of the present invention is based on an optical disc master used for duplication of an optical disc on which an uneven pattern corresponding to a desired information signal is formed in advance. To obtain an electroformed film having an inverted concavo-convex pattern in which the concavo-convex shape is the reverse of the concavo-convex pattern, and in the method for producing a drum stamper, which is produced by adhering this electroformed film to the cylindrical surface of the cylinder, the electroformed film is separated from the optical disc master. After the adhesive layer is formed on the electroformed film before forming, the cylindrical surface of the cylinder is pressure-bonded to the edge of the adhesive layer, and the electroformed film is peeled off while adhering to the cylindrical surface. I am trying.

In order to solve the above-mentioned problems, a method for manufacturing a drum stamper according to a fourth aspect of the present invention is based on an optical disc master used for duplication of an optical disc on which an uneven pattern corresponding to a desired information signal is formed in advance. In the method of manufacturing a drum stamper having an inverted concavo-convex pattern in which the concavo-convex shape is the reverse of the concavo-convex pattern on the cylindrical surface, the drum-type stamper is manufactured based on a flexible optical disk master.

In order to solve the above-mentioned problems, a method for manufacturing a drum stamper according to a fifth aspect of the present invention is based on an optical disc master used for duplication of an optical disc on which an uneven pattern corresponding to a desired information signal is formed in advance. A method of manufacturing a drum stamper having an inverted concavo-convex pattern in which the concavo-convex shape is the reverse of the concavo-convex pattern on a cylindrical surface, and a step of producing an optical disc master using a flexible substrate having flexibility (for example, a plastic substrate). A step of forming a conductive film (for example, a nickel film) on the optical disk master and then forming the optical disk master and the conductive film into a cylindrical shape so that the conductive film is an inner surface; And a step of laminating an electroformed layer (for example, a nickel electroformed layer) on the inner surface.

In order to solve the above-mentioned problems, a method for manufacturing a drum stamper according to a sixth aspect of the present invention is such that the cylindrical optical disk master and the conductive film according to the fifth aspect of the present invention are fitted into a cylinder frame, It is characterized in that after the outer surface of the cylindrical optical disk master is brought into close contact with the inner surface of the cylinder frame, an electroformed layer (for example, nickel electroformed layer) is laminated on the inner surface of the cylindrical conductive film.

[0016]

According to the structure of claim 1, since the flexible substrate has flexibility, for example, after the conductive film is formed on the optical disk master, the optical disk master and the optical disk master are formed so that the conductive film becomes the inner surface. It is possible to roll the conductive film into a cylindrical shape. Thus, by stacking the electroformed layer on the inner surface of the cylindrical conductive film, the electroformed layer can be directly used as a high-quality drum stamper.

If the flexible substrate is made of plastic, the optical disc master can be easily cut into a desired size. This makes it possible to easily provide optical disc masters of various sizes (or various numbers of duplicates) that are suitable for the optical disc duplication process that follows the optical disc master disc manufacturing process.

According to the second aspect of the invention, when the stamper is manufactured by the usual method including the first step and the second step, the thermosetting or ultraviolet curable resin layer formed on the substrate is , 2P (Phot
The second optical disk master on which the plurality of concave-convex patterns are formed can be easily manufactured only by repeating the Polymerization) method or the thermocompression bonding method. Therefore, it becomes possible to easily provide optical disc masters of various sizes (or various numbers of duplications) suitable for the optical disc duplication process following the optical disc master production process.

According to the third aspect of the invention, since the electroformed film before being peeled off from the optical disk master is peeled off while adhering to the cylindrical surface of the cylinder, an appropriate tension is applied in the surface direction of the electroformed film. be able to. As a result, the degree of adhesion between the electroformed film and the cylindrical surface of the cylinder is increased, and it becomes difficult for residual air bubbles and deformation such as wrinkles to occur. In addition, the risk of damaging the electroformed film or the adhesion of dust or the like is greatly reduced compared to the case where the electroformed film is peeled from the optical disc master and then adhered to the cylindrical surface of the cylinder.

According to the structure of claim 4, since the optical disk master has flexibility, it is possible to manufacture a high quality drum stamper. If the optical disc master is not flexible, it is essential to peel off the electroformed film formed on the optical disc master from the optical disc master and adhere it to the drum stamper body in order to manufacture the drum stamper. Become. However, if the optical disc master has flexibility, the optical disc master can be rolled into a cylindrical shape with the surface on which the concavo-convex pattern is formed inside, so there is an unprecedented innovation in electroforming the drum stamper itself. Can provide various technologies.

Further, according to the fifth aspect of the invention, since the optical disc master is manufactured by using the flexible substrate having flexibility, the optical disc master and the conductive film are made cylindrical so that the conductive film becomes the inner surface. Will be possible. This makes it possible to produce a high-quality drum-type stamper from which factors such as peeling and deformation of the stamper have been eliminated by simply laminating the electroformed layer on the inner surface of the cylindrical conductive film.

Further, according to the sixth aspect of the invention, since the circularity of the optical disk master and the conductive film is maintained by the cylinder frame, it is possible to manufacture a higher quality drum stamper having a high circularity.

When the surface of the conductive film is passivated before the electroformed layer is laminated on the inner surface of the cylindrical conductive film, the surface of the conductive film is protected and the laminated electroformed layer is peeled off. Will be easier.

[0024]

【Example】

[Embodiment 1] An embodiment of an optical disk master and a method for manufacturing the same according to the present invention will be described below with reference to FIGS. 1 to 3.

First, as shown in FIG. 2A, the ultraviolet curable resin 9 is uniformly applied to the flat glass substrate 8 which has been smoothed and washed. The size of the glass substrate 8 may be determined in consideration of the number of masters to be formed on the glass substrate 8, the size of the conductive film forming device, the size of the electroforming processing device, and the like. The coated surface of the glass substrate 8 is smoothed so that the surface roughness R _max is usually 5 to 20Å.

In the present embodiment, the size of the glass substrate 8 is 300 mm × 500 mm and the thickness is 2 mm in order to manufacture six masters for the glass substrate 8. Further, as the ultraviolet curable resin 9, for example, MP-107 manufactured by Mitsubishi Rayon Co., Ltd., Dicure Clear STM-401 manufactured by Dainippon Ink and Chemicals, Inc., or the like is suitable. Any coating method may be used as long as the resin film thickness can be made uniform, and for example, a spin coating method or a roll coating method can be used. The coating thickness of the ultraviolet curable resin 9 may be about 50 μm, and the film thickness after curing may be about 20 to 30 μm. Of course, it is possible to make it thinner than this.

Next, as shown in FIGS. 2 (b) and 2 (c), a disk-shaped stamper 10 manufactured by a known method as described in the conventional example is pressure-bonded to the ultraviolet curable resin 9, and the stamper 10 is pressed. The uneven pattern of is transferred. Then, as shown in FIG. 2D, the ultraviolet curable resin 9 is irradiated with ultraviolet rays 11 from the glass substrate 8 side to cure the ultraviolet curable resin 9. At this time, as shown in FIG. 1, in order to prevent the non-master disk forming region of the ultraviolet curable resin 9 from being cured,
It is preferable to use the shielding hood 12 that limits the irradiation area of the ultraviolet rays 11.

After the ultraviolet curable resin 9 on the portion of the stamper 10 to which the concavo-convex pattern is transferred is cured, the stamper 10
When is peeled off, the master recording portion 9a is obtained as shown in FIG. After that, with respect to the uncured non-master disk forming region of the ultraviolet curable resin 9, the areas shown in FIGS.
By repeating the above process, as shown in FIG. 3, it is possible to easily obtain a sheet-shaped master 8a having, for example, six master recording portions 9a.

Instead of the ultraviolet curable resin 9, a thermosetting resin may be used. In this case, stamper 1
After 0 is heated, the thermosetting resin is pressure-bonded and cured to transfer the concave-convex pattern of the stamper 10. Further, the size of the glass substrate 8 can be arbitrarily determined according to the number of master recording portions 9a formed.

In order to manufacture a stamper having six concavo-convex patterns based on the sheet-shaped master 8a, it is necessary to stabilize the surface on which the master recording portion 9a is formed and promote mold releasability. Therefore, as shown in FIG.
After forming the nickel film 13 on the formation surface of the master recording portion 9a by a method such as sputtering or vapor deposition,
The sheet-shaped master 8a is dipped in a 5 wt% potassium dichromate aqueous solution to form a nickel passivation film on the surface of the nickel film 13. The thickness of the nickel film 13 is 100 to 20.
It was about 0Å, and the immersion time was about 1 minute. The nickel film 13 can also be formed of silver or chromium.

The nickel passivation film described above can also be formed by oxygen plasma treatment. The oxygen plasma treatment is performed on the sheet-shaped master 8a, for example, under conditions of an oxygen gas pressure of 6 mmTorr and an electric power of 150 W for 3 minutes.

Thereafter, as shown in FIG. 2 (g), the sheet-shaped master 8a which has been subjected to the passivation treatment is subjected to electroforming treatment to form a nickel electroforming layer 14 having a thickness of 0.3 mm according to a usual method.
By peeling off the nickel electroformed layer 14 from the sheet-shaped master 8a, a sheet-shaped stamper 15 having a concavo-convex pattern is obtained as shown in FIG. 2 (h). Sheet-shaped stamper 1
If No. 5 is used, a plurality of (6 in this embodiment) optical disks can be duplicated at one time.

In order to cut and use the sheet-shaped master 8a as needed, it is preferable to use a plastic substrate such as polycarbonate or acrylic instead of the glass substrate 8. For plastic substrates,
The sheet-shaped master 8a is manufactured through similar manufacturing steps corresponding to FIGS. 2B to 2E. After that, if necessary, the sheet-shaped master 8a is cut into a desired size, and as shown in FIG.
A sheet-shaped stamper 15 having a desired size is obtained through similar manufacturing steps corresponding to (h). Since the substrate is made of plastic, the sheet-shaped master 8a can be cut more easily than in the case of glass. In this case, there is an effect that the sheet-shaped master 8a having a size suitable for the conductive film forming step, the electroforming step, etc. can be easily provided.

[Embodiment 2] Next, an embodiment of a method of manufacturing a drum stamper according to the present invention will be described with reference to FIG. For convenience of explanation, members having the same functions as those of the members shown in the drawings of the above-described embodiment are designated by the same reference numerals, and the description thereof will be omitted.

In the same manner as the steps corresponding to FIGS. 2 (a) to 2 (g), the sheet-shaped master 8a that has been subjected to the passivation treatment is subjected to electroforming treatment. At this time, the thickness of the nickel electroformed layer 14 is set to about 50 μm. After that, as shown in FIG. 4A, an adhesive is applied on the nickel electroformed layer 14 to provide an adhesive layer 16. However, since the surface roughness R _max of the nickel electroformed layer 14 is about 5 μm, the thickness of the adhesive layer 16 is set to about 10 μm so as to cover the surface roughness R _max.
m. As a result, it is possible to save the labor of polishing the surface of the nickel electroformed layer 14 as in the conventional case. In addition,
The adhesive is applied uniformly by spin coating, roll coating, or the like.

Next, as shown in FIG. 4B, for example, a metal cylinder 17 is pressure-bonded to the edge of the sheet-shaped master 8a, and then the nickel electroformed layer 14 is formed as shown in FIG. 4C. Take up. The adhesive force between the nickel electroformed layer 14 and the passivated nickel film 13 is
Since it is weaker than the adhesive force acting between the nickel electroformed layer 14 and the nickel electroformed layer 14, the nickel electroformed layer 14 is easily peeled off during winding. In this way, as shown in FIG. 5, the drum stamper 18 having a plurality of concavo-convex patterns can be obtained by a simple winding operation only once. If the drum stamper 18 is used, a plurality of flexible optical disks can be duplicated at one time on a flexible substrate that is continuously fed.

As described above, since the nickel electroformed layer 14 is taken up while being adhered to the cylinder 17 at the same time as the peeling, the nickel electroformed layer 14 has a uniform adhesive force and a peeling force acting in the surface direction. Tension is applied. For this reason,
The nickel electroformed layer 14 is less likely to be deformed such as wrinkles, and bubbles are less likely to remain. Further, the chances of dust and the like entering between the cylinder 17 and the nickel electroformed layer 14 are reduced, and the risk of damaging the signal surface of the nickel electroformed layer 14 having the concavo-convex pattern is also reduced.

[Third Embodiment] Next, another embodiment of the method for manufacturing a drum stamper according to the present invention will be described with reference to FIGS. 6 and 7.
For convenience of explanation, members having the same functions as those of the members shown in the drawings of the above-described embodiments are designated by the same reference numerals, and the description thereof will be omitted.

In this embodiment, since the sheet-shaped master 8a is rolled into a cylindrical shape, a plastic substrate 8'is used instead of the glass substrate 8 shown in FIG. 2 (a). Then, as shown in FIG. 6A, the sheet-shaped master 8a, which has been subjected to the passivation treatment in the same manner as in the above-described embodiments, is formed into a cylindrical shape with the formation surface of the master recording portion 9a inside. The seam of the cylindrical surface is sealed and fixed by rounding and a thin plate 19 made of plastic. The thin plate 19 has the functions of preventing the seam of the cylindrical surface from coming off during electroforming, and of preventing unnecessary nickel from accumulating on the seam.

Roll-shaped master 8 produced in this way
While b is immersed in the electrolytic solution, as shown in FIG. 6B, the anode rod 12 made of titanium (or platinum, stainless steel, etc.) is inserted into the center of the roll-shaped master 8b. Then, the nickel film 13 formed as described above on the formation surface of the master recording portion 9a is electrified as a cathode, and the current is applied as shown in FIG.
As shown in, a nickel electroformed layer 20 is deposited. After the deposition, the thin plate 19 sealing the seam is removed, and the roll-shaped master 8b is unfolded to obtain a drum stamper 21 having a plurality of concave-convex patterns formed on its surface, as shown in FIG.

The drum type stamper 21 obtained by the manufacturing method of the present embodiment is similar to the second embodiment in that the nickel electroformed layer 1 is used.
Unlike the drum type stamper 18 to which 4 is attached, the drum portion and the stamper portion are integrated. Therefore,
Since the peeling and the deformation of the stamper portion do not pose a problem, the quality of the drum type stamper 21 is dramatically improved.

[Embodiment 4] Next, still another embodiment of the method for manufacturing a drum stamper according to the present invention will be described with reference to FIGS. 8 and 9. For convenience of explanation, members having the same functions as those of the members shown in the drawings of the above-described embodiment are designated by the same reference numerals, and the description thereof will be omitted.

A roll-shaped master 8b rolled into a cylindrical shape in the same manner as in the third embodiment is brought into close contact with the inner surface of a cylinder 22 made of metal or plastic, as shown in FIG. 8 (a).

Thereafter, similarly to the third embodiment, the nickel electroformed layer 20 is deposited on the inside of the roll-shaped master 8b. After the deposition is completed, as shown in FIG. 8B, by removing the cylinder 22 and developing the roll-shaped master 8b, a drum-type stamper 21 similar to that of the third embodiment is obtained.

In this case, since the outer shell of the roll-shaped master 8b is constrained by the cylinder 22, if the nickel electroformed layer 20 is deposited so that the compressive stress remains evenly during the electroforming, the roll-shaped master 8b can be formed. Is strongly pressed against the inner surface of the cylinder 22, so that the roundness of the roll-shaped master 8b is not easily broken, and a higher quality drum stamper can be manufactured.

By the way, when a plurality of flexible optical disks are duplicated at a time by the thermocompression bonding method using the drum stamper 21, depending on the relationship between the formation direction of the uneven pattern and the rotating direction of the drum stamper 21, the uneven pattern is formed. Transfer rate changes.

In order to make the transfer rate uniform, for example, the temperature of the portion where the transfer rate is bad may be raised and the temperature of the portion where the transfer rate is good may be lowered.

In order to achieve this object, as shown in FIG. 9 (a), the energization is temporarily stopped during the deposition of the nickel electroformed layer 20, and a nichrome wire or the like is formed at a portion where the transfer rate needs to be increased. The heating wires 23 are arranged in a nested manner so that the temperature distribution of the drum stamper 21 can be changed according to the change of the transfer rate. When the energization is restarted after the heating wire 23 is arranged, the nickel electroformed layer 20 is deposited so as to enclose the heating wire 23. Thus, as shown in FIG.
A drum-type stamper 24 having the heating wire 23 built therein is obtained.

[0049]

As described above, the optical disk master according to the invention of claim 1 has a flexible substrate having flexibility, and a resin layer having a plurality of the concavo-convex patterns corresponding to duplication of a plurality of optical disks. It is composed of.

Therefore, after the conductive film is formed on the optical disk master, the optical disk master and the conductive film can be rolled into a cylindrical shape so that the conductive film becomes the inner surface, and further, the cylindrical conductive film. It is possible to form a high quality drum stamper by laminating an electroformed layer on the inner surface of the.

As described above, the method of manufacturing the optical disk master according to the invention of claim 2 has the first concave and convex pattern corresponding to the information signal based on the desired information signal recorded in advance on the optical disk. A first step of producing an optical disc master, a second step of producing a stamper having an inverted concavo-convex pattern in which the concavo-convex shape is the reverse of the concavo-convex pattern based on the first optical disc master, and a thermosetting type on a substrate. An ultraviolet-curing resin layer is formed, the stamper is pressure-bonded to one area of the resin layer, the stamper pressure-bonding portion is cured, and the third step of transferring the concave-convex pattern is performed. By repeating the third step, the second pattern having the plurality of uneven patterns is formed.
And a fourth step of producing the optical disk master.

Therefore, only by repeating the 2P method or the thermocompression bonding method using the stamper, it is possible to easily manufacture the second optical disk master on which the plurality of concave-convex patterns are formed. Further, it is possible to easily provide the optical disc masters of various sizes or various duplication numbers which are suitable for the optical disc duplication process following the optical disc master production process.

As described above, the method of manufacturing the drum stamper according to the third aspect of the present invention forms the adhesive layer on the electroformed film before it is peeled from the optical disc master, and then the edge of the adhesive layer is formed. The cylinder surface of the cylinder is pressure-bonded, and the electroformed film is peeled off while adhering to the cylinder surface.

Therefore, the degree of adhesion between the electroformed film and the cylindrical surface of the cylinder is increased, and it becomes difficult for residual air bubbles and deformation such as wrinkles to occur. Further, when the electroformed film is adhered to the cylindrical surface of the cylinder, there is an effect that the risk of damaging the electroformed film or adhesion of dust or the like is significantly reduced.

As described above, the method of manufacturing the drum stamper according to the fourth aspect of the present invention is configured to manufacture the drum stamper based on the flexible optical disk master.

Therefore, since the optical disk master can be rolled into a cylindrical shape with the surface on which the concave-convex pattern is formed inside, it is possible to provide an unprecedented novel technique of electroforming the drum stamper itself. Produce an effect.

As described above, in the method for manufacturing a drum stamper according to the present invention, a step of producing an optical disk master using a flexible substrate having flexibility, and a conductive film formed on the optical disk master. After that, the step of forming the optical disc master and the conductive film into a cylindrical shape so that the conductive film becomes the inner surface, and the step of laminating an electroformed layer on the inner surface of the cylindrical conductive film.

Therefore, by simply laminating the electroformed layer on the inner surface of the cylindrical conductive film, it is possible to produce a high quality drum stamper from which factors such as peeling and deformation of the stamper are removed. Play.

In the method for manufacturing a drum stamper according to the invention of claim 6, as described above, in addition to the configuration of claim 5,
The cylindrical optical disk master and the conductive film are fitted into the cylinder frame, the outer surface of the cylindrical optical disk master is brought into close contact with the inner surface of the cylinder frame, and then an electroformed layer is laminated on the inner surface of the cylindrical conductive film. It is a composition.

Therefore, it is possible to produce a higher quality drum type stamper having a high roundness.

[Brief description of drawings]

FIG. 1 is a perspective view showing a method for manufacturing an optical disc master according to the present invention.

2A to 2E are vertical cross-sectional views showing a manufacturing process of an optical disk master according to the present invention, and FIGS. 2F to 2H are manufacturing processes of a stamper.

FIG. 3 is a perspective view showing an optical disc master manufactured by the manufacturing method of FIGS. 1 and 2.

FIG. 4 is a vertical sectional view showing a method of manufacturing a drum stamper according to the present invention.

5 is a perspective view showing a drum stamper manufactured by the manufacturing method of FIG. 4. FIG.

FIG. 6 is a perspective view showing another method of manufacturing the drum stamper according to the present invention.

7 is a perspective view showing a drum stamper manufactured by the manufacturing method of FIG. 6. FIG.

FIG. 8 is a perspective view showing still another method of manufacturing the drum stamper according to the present invention.

FIG. 9 is a perspective view showing a method of manufacturing a drum stamper having a heater built therein.

10A to 10C are vertical sectional views showing a conventional optical disc master manufacturing process and FIGS. 10D to 10F, respectively, showing a conventional stamper manufacturing process.

[Explanation of symbols]

 8 Glass Substrate (Substrate) 8'Plastic Substrate (Flexible Substrate) 8a Sheet-shaped Master 8a (Second Optical Disc Master) 9 UV-Curable Resin 10 Stamper 13 Nickel Film (Conductive Film) 14 Nickel Electroformed Layer (Electroformed Film) 16 Adhesive Layer (Adhesive Layer) 17 Cylinder 18 Drum Type Stamper 20 Nickel Electroformed Layer (Electroformed Layer) 21 Drum Type Stamper 22 Cylinder (Cylinder Frame)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kenji Ota 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Inside Sharp Corporation

Claims (6)

[Claims] 1. An optical disc master used for duplication of an optical disc on which an irregular pattern corresponding to a desired information signal is formed in advance. A flexible substrate having flexibility, and a plurality of the irregular patterns corresponding to duplication of a plurality of optical discs. An optical disc master, comprising: a resin layer on which is formed. 2. A first step of producing a first optical disc master having an uneven pattern corresponding to the information signal based on a desired information signal recorded in advance on the optical disc, and the first optical disc master. Based on the second step, a stamper having an inverted concavo-convex pattern in which the concavo-convex shape is reversed from the concavo-convex pattern is formed; After crimping the above stamper,
By repeating the third step of curing the stamper pressure-bonded portion and transferring the concavo-convex pattern and the third step over the entire area of the resin layer, a second optical disk master having a plurality of the concavo-convex patterns formed thereon is obtained. A method of manufacturing an optical disk master, which comprises a fourth step of manufacturing. 3. An electroformed film having an inverted concavo-convex pattern in which the concavo-convex shape is the reverse of the concavo-convex pattern based on an optical disc master used for duplication of an optical disc on which a concavo-convex pattern corresponding to a desired information signal is formed in advance, In a method for manufacturing a drum stamper, which is produced by adhering this electroformed film to the cylindrical surface of a cylinder, after forming an adhesive layer on the electroformed film before being peeled from the optical disc master, the edge of this adhesive layer is A method for manufacturing a drum-type stamper, characterized in that the cylindrical surface of the cylinder is pressure-bonded, and the electroformed film is peeled off while adhering to the cylindrical surface. 4. A drum stamper having, on a cylindrical surface, an inverted concavo-convex pattern in which the concavo-convex shape is the reverse of the concavo-convex pattern based on an optical disc master used for duplication of an optical disc on which a concavo-convex pattern corresponding to a desired information signal is formed in advance. The method for manufacturing a drum-type stamper, wherein the drum-type stamper is manufactured based on a flexible optical disk master. 5. A drum-type stamper having, on a cylindrical surface, an inverted concavo-convex pattern in which the concavo-convex shape is reversed from the concavo-convex pattern based on an optical disc master used for duplication of an optical disc on which a concavo-convex pattern corresponding to a desired information signal is formed in advance. In the manufacturing method, the step of manufacturing an optical disc master using a flexible substrate having flexibility, and after forming a conductive film on the optical disc master, the optical disc master and the conductive master are formed so that the conductive film becomes an inner surface. A method of manufacturing a drum stamper, comprising: a step of forming a film into a cylindrical shape; and a step of laminating an electroformed layer on the inner surface of the cylindrical conductive film. 6. The cylindrical optical disk master and the conductive film are fitted into a cylinder frame, the outer surface of the cylindrical optical disk master is brought into close contact with the inner surface of the cylinder frame, and then the inner surface of the cylindrical conductive film is fitted. The method for manufacturing a drum stamper according to claim 5, wherein electroformed layers are laminated.