JPH1086190A - Mold for molding optical disc board and stamper mounting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for assembling a mold for molding an optical disc board to efficiently mount the mold for forming a thin and accurate optical disc board and a stamper by making a thickness of a cavity from its inner periphery to its outer periphery uniform, and smoothing the introduction of molten resin and its filling in the cavity. SOLUTION: An upper surface of an inner periphery retainer 5 of a stamper 4 to be inserted to a center side of a lower mold 3 for placing and supporting the stamper is provided in plane with an upper surface of the stamper 4. A gap of a cavity 10 is made from an inner peripheral side toward an outer peripheral side uniform, and flow of molten resin is smoothed. When a stamper inner periphery retainer 5 is set, the stamper 4 is set by using the retainer with a pawl for holding the stamper 4, and then the normal retainer 5 is set to a predetermined position or the retainer 5 is set to a predetermined position by using a jig for setting the retainer. Thus, a mounting efficiency of the retainer 5 can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical disk substrate molding die for molding a read-only type, write-once type or rewritable type optical disk substrate and a stamper mounting method, and more particularly to a thin optical disk substrate. The present invention relates to an optical disk substrate molding die and a stamper mounting method suitable for the present invention.

[0002]

2. Description of the Related Art At present, various types of optical disks of a read-only type, a write-once type and a rewritable type are used as new information recording media. An optical disk can carry a large amount of information at a high density, but it is required to further increase its capacity. In many cases, the substrate used for this optical disk is formed of a resin, and has conventionally been formed by a molding die shown in FIG.

As shown in FIG. 9, a mold 1a for molding an optical disk substrate is roughly divided into a movable mold having a sprue bush 2a, a fixed mold 3a, a stamper 4a, a stamper inner peripheral presser 5a, and a cavity ring 6a. 7a, a cut punch 8a, and a vacuum suction groove 9 formed on the fixed mold 3a side.
a. The stamper 4a is mounted in contact with the stamper-side mirror surface of the fixed mold 3a, and the sprue bush 2a is provided in a gap (cavity) 10a between the movable mold 7a having the mirror-side mirror surface formed on the lower surface and the surface of the stamper 4a. A molten resin is introduced from the side as shown by the arrow, and the gap 10a is filled to form an optical disk substrate. In the case of the conventional optical disk substrate molding die 1a, a claw 11 for engaging and holding the stamper 4a is formed on the stamper inner peripheral presser 5a.
The stamper 4 is held by the stamper inner peripheral retainer 5a using
a was attached and detached. The claw 11 protrudes into the gap 10a during molding as shown in the figure.

[0004]

As a method for increasing the density and capacity of information stored on an optical disk, it is necessary to shorten the wavelength of a laser beam for reading or writing information on the optical disk. . Further, the numerical aperture (N
There is a need to make A) larger. Considering the realization of high-density and high-capacity optical disks from the viewpoint of optical disk media that can actually store information, it is necessary to reduce the thickness of optical disks as the wavelength of laser light becomes shorter and NA increases. .

As described above, an optical disk substrate is formed by filling a mold cavity with a resin such as polycarbonate by injection molding or injection compression molding as described above.
It is manufactured by forming a recording layer, a reflective layer, a protective layer and the like on the optical disk substrate. In addition, it is the optical disk substrate that substantially determines the thickness of the optical disk, and it is necessary to make the optical disk substrate thinner in order to make the optical disk thinner. On the optical disk substrate, a pit row usually meaning information contained therein or a guide groove necessary for writing information from now on is transferred. These pit rows and guide grooves are engraved on a stamper mounted on one side of the mold cavity, and are transferred to the optical disk substrate by sufficiently filling the cavity with molten resin having high fluidity and pressure. Let me.

Incidentally, in order to make the optical disk substrate thinner, the cavity thickness of the mold for molding the optical disk substrate may be reduced to a target thickness. However, when the cavity thickness of the mold is reduced, the resin does not easily flow in the cavity, and it becomes difficult to transfer the above-described pit rows and guide grooves to the optical disk substrate. In addition, pit rows and guide grooves to be transferred are more densely carved for higher density and larger capacity, so that more difficult transfer is required.

As described above, in the conventional mold 1a for molding an optical disk substrate, the stamper 4a is attached and detached by the stamper inner periphery presser 5a having the claw 11. The stamper inner peripheral presser 5a has a function of pressing the inner peripheral portion of the stamper 4a so that the inner peripheral portion of the stamper 4a does not separate from the cavity surface of the mold by its claw 11, and performing centering of the mounting position of the stamper 4a with its body. It is.

However, since the claws 11 are set so as to protrude into the cavity 10a as described above, when the molten resin is introduced into the cavity 10a, the claws 11 impede the flow of the resin, and the claw 11 enters the cavity 10a. Inhibits smooth filling of the resin. For this reason, substrate characteristics such as transferability and birefringence of pits and guide grooves of the optical disk substrate to be formed deteriorate. This tendency becomes more conspicuous as the optical disk substrate becomes thinner, and is a major obstacle to making the optical disk substrate thinner.

The present invention has been made in view of the above circumstances, and has been made for each claim to achieve the following object.

According to a first aspect of the present invention, a stamper inner periphery presser having no claw is used, and an upper surface thereof is flush with an upper surface of the stamper.
An object of the present invention is to provide a mold for molding an optical disk substrate, which facilitates filling of the resin during resin molding and forms a thin optical disk substrate. Note that vacuum suction grooves are arranged on the inner peripheral side and the outer peripheral side of the stamper in order to secure the holding of the stamper to the fixed mold.

A second aspect of the present invention is a permeable member having high strength so that the stamper is not deformed and enters the vacuum suction groove engaged with the inner peripheral side and the outer peripheral side of the stamper during molding. An object of the present invention is to provide a mold for molding an optical disk substrate that fills the inside of the vacuum suction groove.

In order to prevent interference between the stamper inner circumference press and the stamper and to form an optical disc substrate with high precision, the temperature of the stamper inner presser and the temperature holding of the stamper are ensured. Accordingly, an object of the present invention is to provide a mold for molding an optical disk substrate that holds a predetermined minute gap.

It is another object of the present invention to provide a method of assembling a mold for molding an optical disk substrate, which allows a stamper to be set accurately and securely by a stamper inner periphery presser having no claw. .

[0014]

SUMMARY OF THE INVENTION In order to achieve the above objects, the present invention provides a sprue bush having a resin introduction passage disposed at a center portion, and a stamper-side mirror surface disposed surrounding the sprue bush. A fixed mold formed on the front,
A stamper mounted on the mirror surface of the fixed mold, a stamper inner periphery presser that is detachably inserted between the fixed mold and the sprue bush and presses the inner peripheral side of the stamper, and holds an outer periphery of the stamper. A movable mold that has a cavity ring that forms a mirror surface of an optical disc and that forms a mirror surface of the optical disk, facing the stamper, and that is set to open and close at a position facing the fixed mold; The stamper includes a cut punch slidably held at the center of the mold and punches a central hole of the optical disc substrate, a vacuum suction groove for holding the stamper on the fixed mold side, and the like. An optical disk substrate molding die for molding an optical disk substrate by filling a gap (cavity) therebetween with a molten resin, wherein a front surface of the stamper inner peripheral presser is flush with a stamper surface. It is collected by the vacuum suction groove formed in the fixed mold side, and constitutes the inner periphery side and the optical disc substrate molding metal mold which is at least disposed on the outer peripheral side of the stamper.

The vacuum suction groove is filled with a permeable member, and the stamper is deformed into the vacuum suction groove by the pressure of the molten resin filled in the gap (cavity). It is characterized by having strength not to be.

The stamper inner periphery presser is temperature-controlled to a set temperature, and a minute gap is formed during molding between the outer periphery of the stamper inner presser and the inner periphery of the stamper surrounding the stamper. At the time, the temperature difference between the stamper inner periphery presser and the stamper is temperature controlled to 50 ° C. or less, and the minute gap is held in a range of 10 μm to 40 μm. A heater is built-in, and a heat insulating layer is formed between the outer periphery of the stamper inner periphery presser and the inner periphery of a fixed mold surrounding the stamper inner retainer.

A sprue bush having a resin introduction path disposed at the center thereof, a fixed die disposed so as to surround the sprue bush and having a stamper-side mirror surface on the front surface, and mounted on the mirror surface of the fixed die. A stamper, a stamper inner circumference presser which is removably inserted between the fixed mold and the sprue bush and presses the inner peripheral side of the stamper, and a cavity ring for holding the outer periphery of the stamper. A movable mold that is formed with a mirror surface side mirror surface to be formed facing the stamper and that is set to be openable and closable at a position facing the fixed mold, and is slidably held at the center of the movable mold; A cut punch for punching the center hole of the optical disc substrate, a vacuum suction groove for holding the stamper on the fixed mold side, and the like, and a gap between the stamper surface and the movable mold. A mold for molding an optical disk substrate by filling a cavity with a molten resin, wherein the front surface of the stamper inner peripheral press is set flush with the surface of the stamper and formed on the fixed die side. A method of mounting a stamper, wherein the vacuum suction groove is formed so as to be disposed at least on an inner peripheral side and an outer peripheral side of a stamper, wherein a stamper inner peripheral presser that protrudes and forms a claw that engages an inner periphery of the stamper is provided. A first procedure for holding the stamper and mounting the stamper on the front surface of the fixed mold, and a second procedure for suction-holding the stamper mounted on the fixed mold to the fixed mold by vacuum in a vacuum suction groove. And removing the stamper inner periphery presser having a claw from the fixed mold side, inserting a predetermined stamper inner periphery presser without a claw into the fixed mold, and before the stamper inner periphery presser. Third step of setting the stamper inner surface flush with the stamper surface, and after molding a predetermined optical disk substrate, taking out the predetermined stamper inner periphery presser without the claw from the fixing mold and fixing the stamper inner periphery presser having the claw. A fourth step of inserting the mold into a mold, engaging the stamper inner peripheral retainer with the stamper and removing the stamper, and sequentially performing the fourth procedure.

Further, a sprue bush having a resin introduction passage disposed at a central portion, a fixed die surrounding the sprue bush and forming a stamper side mirror surface on a front surface, and a fixed die having a mirror surface on the fixed die. A mirror for an optical disk, comprising: a stamper to be mounted; a stamper inner periphery presser that is detachably inserted between the fixed mold and the sprue bush to press an inner peripheral side of the stamper; and a cavity ring that holds an outer periphery of the stamper. A movable mold which is formed with a mirror surface side mirror surface forming a surface facing the stamper and which is set to be openable and closable at a position opposed to the fixed mold, and which is slidable at the center of the movable mold. The stamper includes a cut punch for punching a central inner hole of the optical disc substrate, a vacuum suction groove for holding the stamper on the fixed mold side, and the like, and a gap between the stamper surface and the movable mold. An optical disk substrate molding die for molding an optical disk substrate by filling a gap (cavity) with a molten resin, wherein the front surface of the stamper inner peripheral press is set flush with the stamper surface and formed on the fixed die side. Wherein the vacuum suction groove is formed so as to be arranged at least on the inner peripheral side and the outer peripheral side of the stamper. The stamper mounting method comprises: A first procedure of inserting a front surface of the stamper inner peripheral press into the fixed mold to a position protruding from a surface of a stamper mounted on the fixed mold by a stamper inner peripheral press holding jig for holding an inner press, A second procedure of pressing the stamper with a stamper inner peripheral pressing jig for pressing the stamper inner peripheral side toward the fixed mold side, and a step of pressing the stamper inner peripheral pressing holding jig inside the stamper. A second step of further pressing the presser into the fixed mold to make the front surface of the stamper inner peripheral press flush with the surface of the stamper, and after adsorbing and holding the stamper to the fixed mold, holding the stamper inner peripheral press holding jig. The third step of retracting the tool and the stamper inner peripheral portion pressing jig is performed to set the stamper inner peripheral presser at a predetermined position.

[0019]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is an axial sectional view and a configuration diagram showing the entire structure of the present invention. FIG. 1 is an enlarged view of a portion around a cavity in a closed state of an optical disk molding die.

The optical disk substrate molding die 1 of the present invention comprises a sprue bush 2, a fixed die 3, a stamper 4, a stamper inner peripheral presser 5, a movable die 7 having a cavity ring 6,
The fixed mold 3 is formed with a vacuum suction groove 9 and a vacuum suction groove 12, and the space between the surface of the stamper 4 and the lower surface of the movable mold 7 is filled with a molten resin to form an optical disk substrate. A gap (cavity) 10 for molding is formed.

The sprue bush 2 forms a resin introduction path 13 and is arranged at the center, and communicates with an injection molding machine (not shown).

The fixed mold 3 is disposed so as to surround the sprue bush 2, and a stamper-side mirror surface is formed on the front surface thereof. A vacuum suction groove 9 engaging with the outer peripheral portion of the stamper 4 is provided on the outer peripheral side of the front surface, and a vacuum suction groove 12 engaging with the inner peripheral portion of the stamper 4 is provided on the inner peripheral side of the front surface. Is established.

The stamper 4 is made of a ring-shaped flat plate, and has a pitch line and a guide groove formed on the upper surface thereof, and is mounted on the front surface of the fixed mold 3.

The movable mold 7 is arranged at a position facing the fixed mold 3 and is supported by a movable platen of the molding apparatus so as to be capable of opening and closing. A cavity ring 6 for holding an outer peripheral portion of the stamper 4 is integrally provided on an outer edge side thereof, and a cut punch 8 for punching an inner hole of an optical disk substrate (not shown) can be slid forward and backward at a central portion thereof. Supported by

The stamper inner periphery presser 5 is a main component of the present invention, and is formed of a ring-shaped member without claws 11 as in the prior art, and is provided between the outer periphery of the sprue bush 2 and the inner periphery of the fixed mold 3. It is inserted. The front surface of the stamper inner peripheral presser 5 inserted as shown in the drawing is characterized in that it is held flush with the surface of the stamper 4. A minute gap 14 of δ is formed between the outer periphery of the stamper inner periphery presser 5 and the inner periphery of the stamper 4. The minute gap 14 is necessary for attaching and detaching the stamper inner periphery presser 5. When the molded optical disc substrate is taken out, if the small gap 14 is large, the optical disc substrate is caught by the stamper 4 and the stamper 4 is fixed. Mold 3
Is caused to peel off from the stamper side mirror surface. Therefore, it is necessary to experimentally keep the small gap at about 10 μm to 40 μm. In order to always maintain this clearance during molding, it is necessary to control the temperature around the stamper inner presser 5.

For the above temperature management, for example, a temperature controller 15 or the like is used. Temperature controller 15
Although various types are adopted, it is necessary to control the temperature of the stamper 4 via the stamper inner periphery presser 5 and the fixed mold 3. For example, the difference between the mirror surface temperature control set temperature of the stamper-side mirror surface of the fixed mold 3 and the chiller temperature control (in this example, the temperature control of the sprue bush 2) inside the stamper inner peripheral presser 5 is set to 50 degrees or less. It is necessary. It has been clarified experimentally that when the distance is larger than this, the minute gap 14 greatly changes, and the above-mentioned problem occurs.

As shown in FIG. 1, a heat insulating layer 16 is formed between the inner periphery of the fixed mold 3 into which the outer periphery of the stamper inner periphery press 5 is fitted and the outer periphery of the stamper inner periphery retainer 5. . By forming the heat insulating layer 16, the stamper inner peripheral presser 5 is formed.
Temperature control is more easily performed. In this embodiment, the heat insulating layer 16 is composed of a groove formed on the contact surface between the stamper inner peripheral presser 5 and the fixed mold 3, and is formed as a groove and an air layer. May be inserted.

Further, as shown in FIG. 1, a heater 17 is incorporated in the stamper inner periphery presser 5 to perform a heater control in accordance with a molding process and an ambient temperature, so that temperature control can be more reliably performed and clearance control can be performed. Performed easily and reliably.

As described above, in the case of the present invention, the stamper 4
There is no claw 11 for fixing the stamper on the inner peripheral portion presser 5, so that the holding of the stamper 4 becomes uncertain. To prevent this,
In the present invention, a vacuum suction groove 12 is provided on the fixed mold 3 at a position corresponding to a further inner side of the information recording area of the optical disk substrate. Of course, a vacuum suction groove 9 is also provided on the outer peripheral side of the fixed mold 3. The stampers 4 are formed by the vacuum suction grooves 9 and 12.
By vacuum suction, the stamper 4 is securely held on the fixed mold, and the stamper 4 is prevented from coming off the stamper-side mirror surface of the fixed mold during the molding process.

The vacuum suction grooves 9 and 12 have air permeability that allows vacuum suction and a cavity 10.
When the molten resin is filled therein, the air-permeable member 18 is filled with a strength such that the pressure applied to the stamper 4 does not cause deformation of the stamper 4 at the vacuum suction groove 12. For example, a material having a honeycomb structure with a fine diameter, a porous ceramic, or the like is employed as the gas permeable member 18. Also,
The front surfaces of the vacuum suction grooves 9 and 12 filled with the air-permeable member 18 are flush with the stamper-side mirror surface of the fixed mold 3. Thereby, the deformation or distortion of the stamper 4 is reliably prevented by the filling pressure of the resin filled in the cavity 10.

With the structure described above, the molten resin introduced from the sprue bush 2 is smoothly introduced into the flat cavity 10 which is not obstructed by the claws 11 and the like.
Is filled in. Therefore, the filled and molded optical disk substrate does not have the defect of the substrate characteristic unlike the conventional product, and can be formed to be thinner than the conventional product. Therefore, a high-density and large-capacity optical disk substrate having good substrate characteristics can be manufactured.

As described above, the stamper inner periphery presser 5 not only fixes the stamper 4 on the stamper-side mirror surface, but also aligns the mounting position of the stamper 4 and detaches it. With the stamper inner peripheral presser 5, the workability of attaching and detaching the stamper 4 is poor. Therefore, the optical disk substrate molding die 1 of the present invention is assembled by an assembling method according to the procedure shown in FIGS.

FIG. 2 is a schematic view showing a state where the stamper inner periphery presser 5 having no claw 11 of the present invention is set at a position for use, and the stamper 4 is mounted on the fixed mold 3 as described above. Then, it is suction-fixed by the vacuum suction grooves 9 and 12. In this state, a minute gap 14 having a dimension δ is formed between the stamper 4 and the stamper inner peripheral presser 5. In this state, the movable mold 7 is in a mold open state in which the movable mold 7 is retracted so as not to hinder the work of mounting the stamper.

In the method of assembling the mold according to the present embodiment, the stamper 4 is inserted by a stamper inner periphery presser 5a having a conventional claw 11, as shown in FIG. Therefore, stamper 4
Is set relatively easily and reliably in the correct position. After the stamper 4 is adsorbed and held on the fixed mold 3 by the vacuum of the vacuum suction grooves 9 and 12, the conventional stamper inner periphery presser 5a is removed as shown in FIG. Insert the presser 5 and set it in the correct position shown in FIG. Thus, the setting of the mold for producing the optical disk substrate of the desired quality is completed. When the stamper 4 is removed after molding the optical disk substrate, FIG.
The stamper inner peripheral presser 5 having the claws 11 again as shown in FIG.
a into the fixed mold 3 side. As described above, the work of attaching and detaching the stamper 4 can be facilitated and the positioning accuracy thereof can be improved.

FIGS. 6 to 8 are schematic views for explaining another method for assembling the optical disk substrate molding die of the present invention. First, the stamper inner peripheral presser 5 having no claw 11 of the present invention is held by the stamper inner peripheral presser holding jig 19 and inserted into the fixed mold 3. The stamper inner peripheral press holding jig 19 abuts the inner hole 20 of the stamper inner peripheral press 5 and its front surface 21 to hold the stamper inner peripheral press 5, whereby the stamper inner peripheral press 5 is a fixed die. Set correctly on 3 side.

On the other hand, as shown in FIG. 6, the inner peripheral portion of the stamper 4 is pressed by the inner peripheral pressing jig 22 which is guided by the outer periphery of the stamper inner peripheral holding jig 19 and moves up and down, and the stamper 4 is fixed. It is set closely on the mold 3. Next, the stamper inner peripheral press holding jig 19 is further pushed in so that the front surface 21 of the stamper inner peripheral press 5 coincides with the surface of the stamper 4, and the setting of the stamper inner presser 5 is completed. In this state, the stamper 4 is suction-fixed by the vacuum of the vacuum suction grooves 9 and 12. Next, as shown in FIG. 8, the stamper inner peripheral holding jig 19 and the stamper inner peripheral pressing jig 22 are moved upward. As described above, the stamper inner periphery presser 5 and the stamper 4 are set at correct positions. The operation of removing the stamper 4 is performed in the reverse order.

[0037]

【The invention's effect】

1) According to the mold for molding an optical disk substrate according to the first aspect of the present invention, in molding the optical disk substrate, the cavity thickness is kept constant from the inner circumference to the outer circumference without being narrowed by the stamper inner circumference pressing claw. Therefore, the resin flow is not hindered, and the resin can be filled into the cavity and the pit rows and guide grooves can be more easily transferred, especially when a thin optical disk substrate is formed. Also, since the end face facing the cavity is not flush with the stamper surface, and the molding is performed using the stamper inner circumference press without the claw, the cavity thickness is reduced from the inner circumference. It is possible to provide a cavity structure that is constant over the outer periphery. In addition, since a mechanism for vacuum suction of the inner periphery of the stamper is provided, even when a stamper inner periphery presser having no claw is used, the stamper does not peel off from the inner periphery during molding, and the inside of the cavity is formed during molding. The stamper does not deform due to the pressure of the resin filled in the stamper.

2) According to the optical disk substrate molding die of the second aspect of the present invention, since the vacuum suction groove is filled with a strong permeable member, deformation of the stamper during molding is prevented. Therefore, a high-precision optical disk substrate can be manufactured.

According to the third aspect of the present invention, since the temperature setting range around the inner periphery presser of the stamper is appropriately defined, the inside of the stamper according to the fourth aspect of the present invention is provided. The clearance between the circumferential presser and the inner peripheral portion of the stamper can be kept within a specified range.

4) According to the optical disk substrate molding die of the fourth aspect of the present invention, it becomes clear that a predetermined minute gap is maintained by controlling the temperature in this range. It becomes clear and a high-precision optical disk substrate can be made.

5) According to the mold for molding an optical disk substrate of the fifth aspect of the present invention, there is provided a structure in which a heater for controlling the temperature of the stamper inner peripheral press is built in the stamper inner peripheral press. As a result, the temperature around the inner periphery presser can be appropriately maintained, so that the clearance with the inner periphery of the stamper can be more reliably maintained.

6) According to the mold for molding an optical disk substrate according to the sixth aspect of the present invention, since the heat insulating layer is provided between the stamper inner periphery press and the stamper side mirror surface, the stamper inner periphery press and the stamper inner surface are provided. A mechanism for more reliably maintaining peripheral clearance can work better.

7) According to the method for assembling a mold for molding an optical disk substrate according to the seventh and eighth aspects of the present invention, the stamper can be reliably set, and the efficiency of assembling the mold can be improved. .

[Brief description of the drawings]

FIG. 1 is an axial sectional view showing a structure in which a peripheral portion of a cavity of an optical disk substrate molding die of the present invention is enlarged.

FIG. 2 is a schematic view for explaining an example of a stamper mounting method according to the present invention.

FIG. 3 is a schematic diagram for explaining an example of a stamper mounting method according to the present invention.

FIG. 4 is a schematic view for explaining an example of a stamper mounting method according to the present invention.

FIG. 5 is a schematic diagram for explaining an example of a stamper mounting method according to the present invention.

FIG. 6 is a schematic view for explaining a stamper mounting method of the present invention using a special assembling jig.

FIG. 7 is a schematic view for explaining a stamper mounting method of the present invention using a special assembling jig.

FIG. 8 is a schematic diagram for explaining a stamper mounting method of the present invention using a special assembling jig.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 optical disk substrate molding die 2 sprue bush 3 fixed die 4 stamper 5 stamper inner peripheral holding 6 cavity ring 7 movable die 8 cut punch 9 vacuum suction groove 10 gap (cavity) 11 claw 12 vacuum suction groove 13 introduction path 14 Micro gap 15 Temperature controller 16 Heat insulation layer 17 Heater 18 Air permeable member 19 Stamper inner peripheral holding holding jig 20 Inner hole 21 Front surface 22 Stamper inner peripheral pressing jig

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[Procedure amendment]

[Submission date] November 28, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Brief description of drawings

[Correction method] Change

[Correction contents]

[Brief description of the drawings]

FIG. 1 is an axial sectional view showing a structure in which a peripheral portion of a cavity of an optical disk substrate molding die of the present invention is enlarged.

FIG. 2 is a schematic view for explaining an example of a stamper mounting method according to the present invention.

FIG. 3 is a schematic diagram for explaining an example of a stamper mounting method according to the present invention.

FIG. 4 is a schematic view for explaining an example of a stamper mounting method according to the present invention.

FIG. 5 is a schematic diagram for explaining an example of a stamper mounting method according to the present invention.

FIG. 6 is a schematic view for explaining a stamper mounting method of the present invention using a special assembling jig.

FIG. 7 is a schematic view for explaining a stamper mounting method of the present invention using a special assembling jig.

FIG. 8 is a schematic diagram for explaining a stamper mounting method of the present invention using a special assembling jig.

FIG. 9 is an outline of a main part of a conventional optical disk substrate molding die.
Sectional drawing which shows schematic structure.

[Description of Signs] 1 Mold for forming optical disk substrate 2 Sprue bush 3 Fixed mold 4 Stamper 5 Stamper inner circumference holding 6 Cavity ring 7 Movable mold 8 Cut punch 9 Vacuum suction groove 10 Gap (cavity) 11 Claw 12 Vacuum suction Groove 13 Introducing path 14 Micro-gap 15 Temperature controller 16 Heat insulation layer 17 Heater 18 Air-permeable member 19 Stamper inner circumference holding jig 20 Inner hole 21 Front surface 22 Stamper inner circumference pressing jig

Claims (8)

[Claims] 1. A sprue bush having a resin introduction passage disposed at a center thereof, a fixed die surrounding the sprue bush and having a stamper side mirror surface formed on a front surface, and a fixed die having a mirror surface on the fixed die. An optical disc having a stamper to be mounted, a stamper inner periphery presser that is detachably inserted between the fixed mold and the sprue bush and presses the inner peripheral side of the stamper, and a cavity ring that holds the outer periphery of the stamper. A movable mold that is formed with a mirror surface side mirror surface forming a mirror surface facing the stamper and is set to be openable and closable at a position opposed to the fixed mold, and slidable at the center of the movable mold; And a vacuum punch groove for holding the stamper on the fixed mold side, etc., and a gap between the stamper surface and the movable mold. An optical disk substrate molding die for molding an optical disk substrate by filling a molten resin in a space (cavity), wherein the front surface of the stamper inner peripheral press is set flush with the stamper surface and formed on the fixed die side. Wherein the vacuum suction groove to be formed is disposed at least on the inner peripheral side and the outer peripheral side of the stamper. 2. A gas permeable member is filled in the vacuum suction groove, and the stamper is deformed into the vacuum suction groove by the pressure of the molten resin filled in the gap (cavity). 2. A material having strength not to be changed.
4. The mold for molding an optical disk substrate according to item 1. 3. The stamper inner periphery presser is temperature-controlled to a set temperature, and a minute gap is formed between an outer periphery of the stamper inner presser and an inner periphery of the stamper surrounding the stamper during molding. The mold for molding an optical disk substrate according to claim 1, wherein: 4. During molding, the temperature difference between the stamper inner periphery presser and the stamper is controlled to 50 ° C. or less, and the minute gap is 10 μm to 40 μm.
The mold for molding an optical disk substrate according to claim 3, wherein the mold is held within a range of m. 5. The mold for molding an optical disk substrate according to claim 3, wherein the stamper inner periphery presser has a built-in heater. 6. The optical disc substrate forming metal according to claim 3, wherein a heat insulating layer is formed between an outer periphery of the stamper inner periphery presser and an inner periphery of a fixed mold surrounding the stamper inner retainer. Type. 7. A sprue bush having a resin introduction passage disposed at a central portion, a fixed die surrounding the sprue bush and having a stamper-side mirror surface formed on a front surface, and a fixed die on the mirror surface of the fixed die. A mirror for an optical disk, comprising: a stamper to be mounted; a stamper inner periphery presser that is detachably inserted between the fixed mold and the sprue bush to press an inner peripheral side of the stamper; and a cavity ring that holds an outer periphery of the stamper. A movable mold which is formed with a mirror surface side mirror surface forming a surface facing the stamper and which is set to be openable and closable at a position opposed to the fixed mold, and which is slidable at the center of the movable mold. A cut punch for punching a central bore of the optical disc substrate, a vacuum suction groove for holding the stamper on the fixed mold side, etc., and a gap between the stamper surface and the movable mold. An optical disk substrate molding die for molding an optical disk substrate by filling a (cavity) with a molten resin, wherein the front surface of the stamper inner peripheral press is set flush with the stamper surface and formed on the fixed die side. A method for mounting a stamper, wherein the vacuum suction groove is formed so as to be disposed at least on an inner peripheral side and an outer peripheral side of the stamper, wherein a stamper inner peripheral presser that protrudes and forms a claw that engages the inner periphery of the stamper. A first procedure of holding the stamper and mounting the stamper on the front surface of the fixed mold;
A second procedure of sucking and holding the stamper mounted on the fixed mold on the fixed mold by vacuum in a vacuum suction groove, and removing the stamper inner peripheral presser having a claw from the fixed mold side, and removing the claw. A third step of inserting a predetermined stamper inner peripheral press into the fixed mold, and setting the front surface of the stamper inner peripheral press to be flush with the stamper surface; and A fourth procedure for removing a predetermined stamper inner peripheral press from the fixed mold, inserting the stamper inner peripheral press having a claw into the fixed mold, engaging the stamper inner peripheral press with the stamper, and removing the stamper. And a method of sequentially mounting the stamper. 8. A sprue bush having a resin introduction passage disposed at a central portion, a fixed die surrounding the sprue bush and having a stamper-side mirror surface formed on a front surface, and a fixed die formed on the mirror surface of the fixed die. A mirror for an optical disk, comprising: a stamper to be mounted; a stamper inner periphery presser that is detachably inserted between the fixed mold and the sprue bush to press an inner peripheral side of the stamper; and a cavity ring that holds an outer periphery of the stamper. A movable mold which is formed with a mirror surface side mirror surface forming a surface facing the stamper and which is set to be openable and closable at a position opposed to the fixed mold, and which is slidable at the center of the movable mold. A cut punch for punching a central bore of the optical disc substrate, a vacuum suction groove for holding the stamper on the fixed mold side, etc., and a gap between the stamper surface and the movable mold. An optical disk substrate molding die for molding an optical disk substrate by filling a (cavity) with a molten resin, wherein the front surface of the stamper inner peripheral press is set flush with the stamper surface and formed on the fixed die side. Wherein the vacuum suction groove is formed so as to be disposed at least on the inner peripheral side and the outer peripheral side of the stamper, wherein the stamper is in contact with an inner hole of the stamper inner peripheral presser and a front surface thereof. A first step of inserting a front surface of the stamper inner peripheral press into the fixed mold to a position protruding from a surface of a stamper mounted on the fixed mold by using a stamper inner peripheral press holding jig for holding the presser; A second procedure of pressing the stamper by a stamper inner peripheral portion pressing jig for pressing an inner peripheral side to the fixed mold side, and the stamper inner peripheral presser by the stamper inner peripheral presser holding jig; A second procedure for further pressing the stamper into the fixed mold to make the front surface of the stamper inner peripheral press flush with the surface of the stamper, and after adsorbing and holding the stamper to the fixed mold, the jig for holding the stamper inner peripheral press; A method of mounting a stamper, comprising performing a third procedure of retracting a stamper inner peripheral portion pressing jig to set the stamper inner peripheral presser at a predetermined position.