JP2001167482A - Method and device for manufacturing optical recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for manufacturing an optical recording medium, capable of rapidly heating the whole of a stumper uniformly to a specified heating temperature, improving the productivity of a disk substrate, and being realized by an inexpensive device. SOLUTION: A heat transfer heater 2 is incorporated in a base lock 1, an evacuation hole 4 is provided in a loading surface 1a having a nonconductive insulating film 3 formed, and a square stumper 5 having a disklike irregular pattern mold 5a such a pit, a groove or the like is placed on the loading surface 1a. By connecting electrode plates 7 and 7 to both ends of the stumper 5 and energizing the plates, the stumper 5 itself is heated by internal resistance, a disk substrate 10 is placed on the heated stumper 5, the disk substrate 10 is pressed by a pressurizer 11, and the irregular pattern of a pit or a groove is thermally transferred.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an optical recording medium of a hot press system in which, for example, a disk substrate is pressed against a stamper in a heated state, and pits and grooves are transferred to the disk substrate. More specifically, the manufacturing apparatus is configured to uniformly heat pits and grooves on the entire disk substrate by uniformly heating the stamper without unevenness in temperature, thereby improving the productivity.

[0002]

2. Description of the Related Art Conventionally, as a hot pressing method for forming an uneven pattern of pits or grooves on a disk substrate made of a plastic sheet such as an optical disk or a magneto-optical disk, a stamper having an uneven pattern mold is heated and heated. There is a method in which a pit or a groove is thermally transferred to a disk substrate by placing a disk substrate on the stamper, melting the surface thereof, and pressing the disk substrate to the stamper with a pressurizer.

Here, a conventional example of a method for heating a stamper is shown in FIGS. FIG. 3 shows a method of mounting and heating a stamper 23 having a concave and convex pattern type 23a of pits and grooves on a base block 22 in which a heat transfer heater 21 is built. At this time, the stamper 23 is evacuated by a plurality of evacuation holes 24 provided on the mounting surface 22a of the base block 22, and the entire stamper 23 is brought into close contact with the mounting surface 22a of the base block 22. It heats evenly. Reference numeral 25 denotes a disk substrate before pits and grooves are formed, and reference numeral 26 denotes a pressurizer for transferring pits and grooves to the disk substrate 25.

FIG. 4 shows a method in which the stamper 23 is covered with a magnetic coil 27, a current is caused to flow through the magnetic coil 27 to generate a high-frequency induction magnetic field, and self-heat is generated by an eddy current generated inside the stamper 23 to heat the stamper. .

[0005]

However, in the method of heating the stamper 23 by the base block 22, since the stamper 23 is heated by the heat of the heat transfer heater 21, the stamper 23 that has once been cooled cannot be heated. It takes time to raise the temperature to the predetermined heating temperature again. Therefore, in the case of the heater heating method, it takes much time to manufacture one disk substrate, and there is a problem in terms of productivity.

On the other hand, the stamper 23
Is advantageous in that the stamper 23 can be rapidly heated, but the method of heating the magnetic coil 2
Due to the shape of the stamper 7 or the misalignment when the stamper 23 is arranged in the magnetic coil, it is difficult to uniformly heat the entire stamper, resulting in uneven temperature. As a result, when the disc substrate is pressed against the stamper 23,
There is a problem in that a portion where pits and grooves are normally thermally transferred and a portion where almost no thermal transfer is performed occur.

Further, a heating method using a high-frequency induction magnetic field includes:
Because the equipment is very expensive and the equipment becomes large,
Considering the overall equipment, the freedom of design is limited,
It will increase the cost.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and can improve the productivity of disk substrates by uniformly and rapidly raising the temperature of a whole stamper to a predetermined heating temperature. It is an object of the present invention to obtain a method and an apparatus for manufacturing an optical recording medium which can be realized with inexpensive equipment.

[0009]

In order to achieve the above-mentioned object, a method of manufacturing an optical recording medium according to the present invention comprises connecting an electrode to a stamper mounted on a base block, and supplying electricity to the stamper. Generate heat by its own internal resistance,
In this method, a substrate is pressed against a stamper to be heated by a pressurizer to thermally transfer an uneven pattern of pits and grooves.

The apparatus for manufacturing an optical recording medium according to the present invention includes a base block provided with a heat transfer heater therein, and provided with a vacuum evacuation hole for sucking and holding the stamper in close contact therewith.
A square-shaped stamper on which a pit or groove uneven pattern mold is placed on the base block facing upward, and connected to both ends of the stamper over the entire width, the stamper is energized and its own internal resistance It is composed of electrodes for generating heat and heating, and a pressurizer for pressing the substrate against the heated stamper and thermally transferring the pits and grooves asperity pattern.

According to the above-described method and apparatus, by connecting an electrode to the stamper and energizing the same, the stamper generates an ohmic loss due to its own internal resistance and self-heats, and the entire stamper is uniformly heated to a predetermined temperature. It can be heated rapidly. The substrate surface is melted by placing the substrate on the stamper in a heated state, and the concave and convex pattern of pits and grooves can be thermally transferred to the substrate by a pressing operation by a pressurizer.

A heat transfer heater is provided on the base block,
Since the stamper placed on the base block is evacuated, the stamper can be placed in close contact with the base block, and the heat from the base block is heated by the heat from the base block, An auxiliary action when the temperature of the stamper is raised can be obtained.

Further, by forming a non-conductive insulating film made of a heat conductive material and having heat conductivity on the base block surface on which the stamper is mounted, when the stamper is energized, the insulating film forms The leakage of current to the stamper is cut off, and the stamper can be heated effectively.

Further, the stamper is formed in a rectangular shape, and the electrodes are brought into contact with high surface accuracy over the entire width of both ends, so that the entire stamper can be uniformly heated to a predetermined temperature. Thus, the uneven pattern of pits and grooves can be thermally transferred uniformly to the entire disk substrate without uneven transfer.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method of manufacturing an optical recording medium according to the present invention will be described below with reference to the drawings, taking a method of manufacturing a disk substrate such as an optical disk as an example.

FIG. 1 is a partial sectional side view of a manufacturing apparatus applied to a method of manufacturing a disk substrate, and FIG. 2 is a plan view of a stamper.

A base block 1, which is a base block of the apparatus, is made of a metal having a high heat conductivity, for example, an aluminum material, and has a built-in heat transfer heater 2 made of a nichrome wire or the like. Base block 1
Are heated to a predetermined temperature.

The upper surface of the base block 1 serves as a mounting surface 1a of a stamper described later, and a bush 1b into which a center hole of a disk substrate described later is inserted projects from the center.
On the mounting surface 1a and the bush 1b, a non-conductive ceramic insulating film (hereinafter, simply referred to as an insulating film 3) made of a heat-resistant material, such as an alumina-based or zirconia-based ceramic, is formed. As a method for forming the insulating film 3, a deposition method such as a PVD method, a CVD method, or a plasma CVD method is used. Alternatively, a plasma spraying method may be used.

In the base block 1 on which the insulating film 3 is formed, a large number of vacuum holes 4 are formed on the mounting surface 1a.

On the mounting surface 1a of the base block 1, a stamper 5 having a circular concave-convex pattern forming die 5a for transferring pits and grooves to a disk substrate.
Is placed. Stamper 5 is made of pure nickel (100%)
Is formed of a material having a large internal resistance, and has a square shape including a disk-shaped concave / convex pattern forming die 5a on the upper surface.

At the left and right ends of the stamper 5, a pair of upper and lower electrode plates 7 made of a conductive material are in contact with the entire width of the stamper 5 with high surface accuracy, and are tightened by bolts 8, 8, respectively. The electrode wires 9 are drawn out of the two electrode plates 7.

In FIG. 1, a disc substrate 10 is made of a material having good light transmittance, such as polycarbonate (PC), polyamide (PA), polyethylene terephthalate (PET),
It is molded from polyacetal (POM) or the like and has a center hole 10a at the center. The pressure plate 11 is a disk substrate 10
Is pressed onto the stamper 5 to transfer a pit or groove uneven pattern onto the disk substrate 10.

Next, a method and a procedure for thermally transferring an uneven pattern of pits and grooves on the disk substrate 10 will be described.

The base block 1 is heated to a predetermined temperature by energizing the heat transfer heater 2 in advance. Then, the center hole of the stamper 5 is inserted into the center bush 1b on the mounting surface 1a of the base block 1 and mounted. Here, air is sucked from each of the vacuum evacuation holes 4 by a vacuum device (not shown) from the air discharge port 4a of the base block 1, and the stamper 5 is attracted onto the mounting surface 1a and brought into a close contact state.

Thereafter, a predetermined current and voltage are applied to the stamper 5 from the electrode wires 9 for a predetermined time (second). As a result, the stamper 5 causes an ohmic loss due to its own internal resistance and rapidly starts self-heating. Then, while adjusting the energizing time, the stamper 5 is set to, for example, 250 ° C. to 300 ° C.
Heat to ° C.

Next, the disk substrate 10 is placed on the heated stamper 5 by inserting the center hole 10a of the disk substrate 10 into the bush 1b of the base block 1. Then, the disk substrate 10 is pressed from above the stamper 5 by the pressurizer 11 with a predetermined pressing force. That is, the disk substrate 10 is placed on the stamper 5 so that the disk substrate 1
The surface of the stamper 5 which is in contact with the stamper 5 is instantaneously melted, and the pits and grooves are thermally transferred to the disk substrate 10 by the pressing operation of the pressurizer 11 so that the pits and grooves of the groove pattern forming die 5a are stamped. Can be done.

Thereafter, the stamper 5 and the disk substrate 10 are moved to a cooling step, and after the disk substrate 10 is solidified, the disk substrate 10 is removed from the stamper 5 to complete a series of manufacturing steps.

Incidentally, in the case of a CD (compact disk), for example, the disk substrate 10 on which the pit or groove uneven pattern is formed is then sputtered with a reflective film of aluminum or the like on the disk surface on which the uneven pattern is formed. An optical disc is manufactured by forming a film by the method described above and forming a protective layer of resin on the reflective film.

As described above, according to the disk substrate manufacturing method of the present invention, the stamper 5 is heated by the stamper 5.
Since the self-heating is performed by the internal resistance of the stamper 5 by directly supplying electricity through the electrodes 7 connected to the stamper 5, the stamper 5 can be quickly heated to a predetermined temperature and heated. Which gives
The manufacturing time of the disk substrate can be shortened, and the productivity can be improved.

In addition, since the non-conductive insulating film 3 is formed on the mounting surface 1a of the base block 1, current leakage to the base block 1 is blocked by the insulating film 3 during energization of the stamper 5. In addition, only the stamper 5 can be energized, and heating can be performed effectively.

The insulating film 3 is non-conductive but has heat conductivity, and is in close contact with the insulating film 3 by the suction of air, so that the base block heated by the heat transfer heater 2 is used. The heat from 1 passes through the insulating film 3 and the stamper 5
Can be heated, whereby the effect of increasing the temperature of the stamper 5 can be effectively assisted.

Further, the stamper 5 is formed in a rectangular shape, and the electrode plates 7, 7 connected with high surface accuracy over the entire width of both ends thereof.
The entire stamper 5 is energized, and the entire stamper 5 can be uniformly heated to a predetermined temperature, thereby placing the stamper 5 on the stamper 5. The entire surface of the disk substrate 10 thus melted can be uniformly melted, and the uneven pattern of pits and grooves can be thermally transferred uniformly over the entire disk substrate 10 without uneven transfer.

The present invention is not limited to the embodiment described above and shown in the drawings, and various modifications can be made without departing from the scope of the invention.

This embodiment can be widely applied to a method of manufacturing disk substrates having various disk diameters, such as a general optical disk, a magneto-optical disk, and an ultra-high-density magneto-optical disk. Even in the case of manufacturing an optical recording medium, a highly reliable recording medium can be manufactured using the above-described apparatus.

[0035]

As described above, according to the method of manufacturing an optical recording medium of the present invention, an electrode is connected to a stamper mounted on a base block and energized, and the internal resistance of the stamper is reduced. The pressurizer presses the substrate to the stamper to be heated, and the concave and convex pattern of the pits and grooves is thermally transferred, so that the stamper can be quickly heated to a predetermined temperature and heated. Can be shortened and the productivity can be improved.

Further, a heat transfer heater is provided on the base block,
Since the stamper mounted on the base block is evacuated, the stamper can be closely mounted on the base block, and the effect of heating the stamper by heat from the base block can be obtained. Accordingly, an auxiliary action when the temperature of the stamper is raised can be obtained.

Further, by forming a non-conductive insulating film made of a heat-resistant material having good heat conductivity on the base block surface on which the stamper is mounted, when the stamper is energized, the insulating film moves toward the base block side. Current leakage is cut off, and the stamper can be effectively heated.

Further, the stamper is formed in a square shape, and the electrodes are brought into contact with high surface accuracy over the entire width of both ends, so that the entire stamper can be uniformly heated to a predetermined temperature. Thus, the uneven pattern of pits and grooves can be thermally transferred uniformly to the entire disk substrate without uneven transfer.

Further, according to the optical recording medium manufacturing apparatus of the present invention, a base block having a heat transfer heater therein, a vacuum block for sucking and holding the stamper in close contact, and a base block. A square stamper with a pit or groove uneven pattern mold placed on top, and connected to the both ends of the stamper over the entire width, energizing the stamper and using its own internal resistance The equipment consists of electrodes for heating and heating, and a pressurizer for pressing the substrate onto the heated stamper to thermally transfer the pits and grooves asperity patterns. It is inexpensive, and the substrate can be manufactured at low cost.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional side view of a disk substrate manufacturing apparatus according to the present invention.

FIG. 2 is a plan view of a stamper.

FIG. 3 is a partial sectional side view of a conventional disk substrate heating device.

FIG. 4 is an explanatory view of another conventional method of heating a disk substrate.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Base block, 2 ... Heat transfer heater, 3 ... Insulating film, 4
... Vacuum drawing hole, 5 ... Stamper, 5a ... Concavo-convex pattern forming die, 7 ... Electrode plate, 10 ... Disk substrate, 11 ... Pressurizer

Continuing on the front page (72) Inventor Nori Minemura 1-10 Kiyohisa-cho, Kuki City, Saitama Prefecture Inside Sony Maxx (72) Inventor Yasutoshi Nihei 6-7-35 Kita Shinagawa, Shinagawa-ku, Tokyo Sony Corporation (72) Inventor Takeo Tobiyama 6-7-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation (72) Inventor Kazuyuki Eshima 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation F Term (reference) 4F213 AC03 AD05 AD08 AG01 AH79 AK05 WA04 WA53 WA58 WA97 WB01 WC01 WK03 5D121 AA02 AA11 DD06 DD07 DD13 DD17 EE26 JJ02

Claims (7)

[Claims] An optical recording medium is manufactured by placing a substrate to be processed on a stamper placed on a base block and being heated, and pressing the substrate, and thermally transferring an uneven pattern of pits and grooves to the substrate. In the method, the stamper is mounted on a base block, and the stamper is heated by its own internal resistance by connecting electrodes to the stamper and energizing the substrate, and the substrate is pressed against the stamper to be heated by a pressurizer. A method for thermally transferring an uneven pattern of pits or grooves by performing thermal transfer. 2. The method of manufacturing an optical recording medium according to claim 1, wherein the base block is provided with a heat transfer heater, and the stamper mounted on the base block is evacuated to a vacuum. A method of manufacturing an optical recording medium, wherein the optical recording medium is held in close contact with a base block. 3. The method of manufacturing an optical recording medium according to claim 1, wherein a nonconductive insulating film having heat conductivity and made of a heat resistant material is formed on the base block surface on which the stamper is mounted. A method for manufacturing an optical recording medium, comprising: 4. The method for manufacturing an optical recording medium according to claim 1, wherein the stamper is formed in a square shape, and both ends thereof are brought into contact with electrodes with high surface accuracy over the entire width. Characteristic method for producing an optical recording medium. 5. The method for manufacturing an optical recording medium according to claim 1, wherein the substrate is one of a disk, a card, and a sheet. 6. A substrate to be processed is placed on a stamper placed on a base block and heated, and pressed, and an uneven pattern of pits and grooves is thermally transferred to the substrate to manufacture an optical recording medium. In the apparatus, a base block having a heat transfer heater inside and a vacuum drawing hole for sucking and holding the stamper in close contact, and a pit or groove concave / convex pattern forming die on the base block is directed upward. An electrode for connecting the stamper to both ends of the stamper over the entire width thereof, energizing the stamper, and generating heat by the internal resistance of the stamper and heating the stamper. An optical system comprising: a pressurizer for pressing the substrate onto the stamper in the heated state to thermally transfer an uneven pattern of pits and grooves. Apparatus for manufacturing a recording medium. 7. The optical recording medium manufacturing apparatus according to claim 6, wherein a non-conductive insulating film having heat conductivity and made of a heat-resistant material is formed on the base block surface on which the stamper is mounted. An apparatus for producing an optical recording medium, comprising: