JPH09123229A - Mold apparatus for molding disk-like recording medium board and molding method for the board using the mold apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attempt to prevent the transfer failure of an uneven pattern such as the pit or groove formed at a stamper and to perform the improvement in the productivity. SOLUTION: This mold apparatus 10 for molding a disk-like recording medium board 1, comprises a fixed mold 11 having a stamper 19 mounted thereat, and a movable mold 12 separably disposed oppositely at the mold 11 to constitute a cavity 13 for molding both the surfaces of the board 1. The apparatus 10 further comprises an outer peripheral mold 21 drivably contained in the outer peripheral mold container 23 provided in the mold 12 and opposed to the mold 11 to mold the outer periphery of the board, and outer peripheral mold driving means for operating to separate the mold 21 from the mold 11. The mold 21 is held in the state opposed to the mold 11 between the mold clamping step and the cooling step by the driving means, and operated to be separated from the mold 12 preferentially to the mold opening operation of the mold 12 on the way of the cooling step.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk-shaped recording medium substrate molding die device for molding a disk-shaped recording medium substrate constituting a disk-shaped recording medium such as an optical disk or a magneto-optical disk with a synthetic resin material. The present invention relates to a method of molding a disk-shaped recording medium substrate using the disk-shaped recording medium substrate molding die device.

[0002]

2. Description of the Related Art Disc-shaped recording media such as optical discs have been provided which use a disc substrate molded of a synthetic resin such as a polycarbonate resin having a light transmitting property. As the disc-shaped recording medium, an optical disc used exclusively for reproduction and a magneto-optical disc capable of rewriting the information signal once recorded in the information signal recording unit are known. Playback-only optical discs are
The pits, which are minute recesses arranged in a pattern corresponding to a predetermined information signal, are formed, and a reflective layer is formed by vapor-depositing aluminum or the like. Further, in a magneto-optical disk, a pre-groove, which is a concentric circular convex portion that constitutes a recording track on which a desired information signal is recorded, is formed on the surface of a disk substrate, and a signal recording layer having a magnetic film is formed. Is configured.

The disc substrate 1 constituting these optical discs and the like is made of a synthetic resin such as a polycarbonate resin having a light-transmitting property, and uses a disc substrate molding die unit installed in an injection molding machine which will be described in detail later. Is molded. As shown in FIG. 11, the disk substrate 1 is provided with a central hole 2 in the center thereof for assembling a hub for magnetic chucking to the disk table on the recording / reproducing apparatus side, and a central hole 2 on the one main surface 3 side. An information signal recording unit 8 is configured concentrically with the information signal recording unit 2. Information signal recording unit 8
Is composed of pits and pregrooves to which the concavo-convex pattern formed on the stamper 109 assembled in the disk substrate molding die device 100 described later is transferred, and is covered with the reflective layer and the protective layer 6. The other main surface 4 of the disk substrate 1 is configured as a reading surface.

As shown in FIG. 9, the disc substrate molding die unit 100 is constructed such that a fixed die 101 forming one main surface 3 of the disc substrate 1 and a fixed die 101 are moved toward and away from the fixed die 101. The movable mold 102 that forms the other main surface 4 of the disk substrate 1 is arranged to face each other, and the outer peripheral mold 201 that forms the outer peripheral portion 7 of the disk substrate 1 can move back and forth to the movable mold 102. It is built and configured.
These fixed mold 101, movable mold 102, and outer peripheral mold 2
01 cooperates in the mold clamped state to form a cavity 103 which is a molding space portion of the disk substrate 1.

Incidentally, the fixed mold 101 and the movable mold 102.
Are attached to and supported by the mold attaching portion of the injection molding machine by a structure whose details are omitted.

The fixed mold 101 faces the movable mold 102 to form the cavity 103, and the cavity forming portion 10
3A is configured as a highly accurate smooth surface, and a stamper 109 having an uneven pattern is attached to form the information signal recording portion 8 on the one main surface 3 of the disk substrate 1. The stamper 109 is attached to the fixed mold 101 while being aligned by an inner peripheral stamper holder and an outer peripheral stamper holder 200 (not shown).

The outer peripheral die 201 is movably incorporated in an outer peripheral die accommodating portion 203 provided in the movable die 102. The outer peripheral die accommodating portion 203 is connected to an air compressor (not shown) outside the disc substrate molding die apparatus 100 via an air passage 204.

The air compressor sends compressed air into the outer peripheral die accommodating portion 203 through the air passage 204. The outer peripheral die 201 is the outer peripheral die storage unit 2
As the atmospheric pressure in 03 increases, it slides toward the fixed mold 101 side. In addition, the air passage 204 is provided in the movable mold 10.
It is provided in several places in 2 so that compressed air can be sent efficiently.

In the outer peripheral die 201, a cavity forming portion 201A for molding the outer peripheral surface portion of the disk substrate 1 is formed as shown in FIG.
As shown in FIG.
A holding concave portion 207 is formed to be formed. When the movable mold 102 moves in a direction away from the fixed mold 101, the holding concave portion 207 causes the outer peripheral convex portion 9 to cause a mold release resistance of the disk substrate 1 formed in the cavity, and the holding substrate 207 forms a mold releasing resistance. 1 is peeled from the stamper 109 attached to the fixed mold and attached to the movable mold 102 side.

An outer peripheral die driving member 202 for retracting the outer peripheral die 201 from the fixed die 101 is attached to the movable die 102 in a die opening step described later.
When the molten material resin 5 is injected into the cavity 103 at a high pressure, the movable mold 102 moves slightly in the direction in which it is separated from the fixed mold 101 by the pressure.
At this time, the outer peripheral die driving member 202 is attached to the outer peripheral die 201.
Together with the movable mold 102, the peripheral mold driving member 202
The stepped portion 20 which is to be escaped in order to prevent the moving operation in the direction of separating from the fixed mold 101 by being pressed by
2A is provided.

The outer peripheral die driving member 202 includes the outer peripheral die 2
An engagement protrusion 202B formed by a step 202A engaging with 01 is provided. The outer peripheral mold 201 moves in conjunction with the movable mold 102 that moves in a direction away from the fixed mold 101 when the engaging protrusion 202B contacts the outer peripheral mold 201.

A ring 205 for sealing is incorporated on the outer peripheral surface side of the outer peripheral mold 201. Further, in the movable mold 102, a sealing ring 206 is incorporated on the main surface in contact with the inner peripheral surface side of the outer peripheral mold 201. The compressed air supplied to the outer peripheral die accommodating portion 203 raises the air pressure in the outer peripheral die accommodating portion 203 without air leakage due to the sealing rings 205 and 206.

The disk substrate molding die apparatus 100 configured as described above molds the disk substrate 1 through the six steps of mold clamping step-injection step-compression step-cooling step-mold opening step-removal step. .

In the disk substrate molding die device 100, the movable die 102 is moved closer to the fixed die 101,
After the mold clamping step for forming the cavity 103 forming the disk substrate 1, the molten material resin 5 is transferred to the cavity 10.
The injection process of injection filling 3 is performed. Next, the disk substrate molding die device 100 moves the movable die 102 closer to the fixed die 101 to move the cavity 1 to the cavity 1.
A compressing step of compressing the material resin 5 filled in 03 is performed, and then a cooling step of cooling and hardening the molten material resin 5 is performed. Next, the disc substrate molding die device 100 is subjected to a mold opening step of moving the movable die 102 in a direction in which the movable die 102 is separated from the fixed die 101, and the disc substrate 1 attached to the movable die 102 side. A take-out process is performed to take out.

[0015]

DISCLOSURE OF THE INVENTION The conventional mold apparatus 100 for molding a disk substrate has a disk substrate 1 during a compression process.
For the purpose of preventing burrs from being generated in the outer peripheral portion 7, the compressed air is supplied from the air passage 204 into the outer peripheral die housing portion 203 to move the outer peripheral die 201 to the fixed die 101 side. In addition, the conventional mold device 100 for molding a disk substrate
In the above, in the compression step, the compression width of the movable mold 102 with respect to the fixed mold 101 is set to be large in order to improve the transferability of the uneven pattern of the stamper 109.

The disc substrate 1 is released from the movable mold 102 by pressing the inner peripheral portion thereof by an eject member (not shown) arranged on the movable mold 102 side. However,
In the conventional disk substrate molding die device 100,
The movement operation of the outer peripheral die 201 was not controlled. Therefore, the outer peripheral mold 201 slid toward the fixed mold 101 side.
During the mold opening step, as shown in FIG.
The engaging convex portion 202B of the outer peripheral die driving member 202 attached to No. 2 does not retract in the releasing direction until the outer peripheral die 201 is pressed and the outer peripheral die 201 is pressed.

Therefore, in the conventional mold apparatus 100 for molding a disk substrate, the disk substrate 1 attached to the movable mold 102 side has the fixed mold 1 on the inner and outer peripheral sides thereof.
01 is not released at the same time but released in a distorted state,
There is a problem that the disk substrate 1 having an optical polarization defect is molded.

Further, in the conventional die device 100 for molding a disk substrate, as shown in FIG. 9, the disk substrate 1 is attached to the stamper 109 side and the stamper 109.
There is a part attached to the mold, and a phenomenon occurs in which the movable mold 102 vibrates in an unstable manner with the releasing operation. As a result, in the conventional disk substrate molding die device 100, the concavo-convex pattern formed on the stamper 109 is multi-transferred onto the disk substrate 1, and the information signal recording unit 8 is transferred onto the disk substrate 1 incorrectly. There was a problem that it did.

On the other hand, the disk substrate molding die apparatus 100
In order to solve the above-mentioned problems, it is considered to take measures to reduce the compression width of the compression process. This measure reduces the probability of occurrence of the above-mentioned problems, but causes a problem that the material resin 5 is not uniformly filled in the cavities to cause distortion inside the disk substrate 1 and the birefringence cannot be reduced. In addition, the transferability of the uneven pattern formed on the stamper 109 is deteriorated.

Further, in the above-described conventional disk substrate molding die device 100, an eject member (not shown) presses the central portion of the disk substrate 1 during the process of taking out the disk substrate 1 so that the disk substrate 1 is movable. Type 1
I took it out from 02. However, in the conventional disk substrate molding die 100, only the central portion is pressed, so that the outer peripheral portion 7 of the disk substrate 1 having the releasing resistance and the central portion of the disk substrate 1 are integrally released. However, there is a problem in that the flatness of the disk substrate 1 deteriorates and the productivity cannot be improved.

Therefore, the present invention solves the above-mentioned problems of the conventional mold apparatus for molding a disk substrate, prevents the transfer failure of the uneven pattern such as pits or grooves formed on the stamper, and improves the productivity. The object of the present invention is to provide a mold device for molding a disk-shaped recording medium substrate that achieves the improvement.

Further, according to the present invention, there is provided a disk-shaped recording medium substrate capable of forming a disk-shaped recording medium substrate which has a good productivity and in which the transfer failure of the uneven pattern such as pits or grooves formed on the stamper is prevented. It is proposed for the purpose of providing a method for molding a disk-shaped recording medium substrate using a molding die device.

[0023]

A mold apparatus for molding a disk-shaped recording medium substrate according to the present invention, which has achieved this object, is a fixed mold having a stamper attached thereto, and is brought into contact with and separated from the fixed mold. A movable mold that forms a cavity that forms both sides of a disk-shaped recording medium substrate by being freely opposed to each other, and moves to a peripheral mold storage portion provided in this movable mold while facing the fixed mold. An outer peripheral die forming an outer peripheral surface portion of the disk-shaped recording medium substrate by being freely accommodated, and an outer peripheral die driving means for moving the outer peripheral die in the outer peripheral die accommodating portion.

Therefore, according to the mold apparatus for molding a disk-shaped recording medium substrate according to the present invention having the above-described structure, the outer peripheral mold is moved from the mold clamping step to the cooling step by the outer peripheral mold driving means. While being held in a state of being opposed to the fixed mold during this period, it is separated from the fixed mold prior to the mold opening operation of the movable mold during the cooling process. Thereafter, the mold device for molding the disk-shaped recording medium substrate is subjected to a mold opening process in which the movable mold is separated from the fixed mold, and the molded disk substrate is satisfactorily attached to the movable mold side. It is attached and released from the mold.

A method for molding a disk-shaped recording medium substrate using the molding die device according to the present invention, which achieves the above-mentioned object, comprises:
A fixed die having a stamper attached thereto, a movable die which is arranged to face the fixed die so as to come into contact with and separate from the fixed die to form a cavity forming both sides of the disk-shaped recording medium substrate, and the movable die. An outer peripheral die for forming an outer peripheral surface portion of the disk-shaped recording medium substrate by being housed in an outer peripheral die storage portion provided in the die so as to face the fixed die and to be movable,
A mold device for molding a disk-shaped recording medium substrate is used, which is provided with a peripheral mold driving means for moving the peripheral mold in the peripheral mold housing.

The disk-shaped recording medium substrate is composed of a mold clamping process in which a movable mold and an outer peripheral mold are interlocked with each other with respect to a fixed mold to form a cavity, and a mold clamping process. An injection step of injecting and filling the melted material resin into the cavity, a compression step of further moving the movable die to the fixed die to compress the material resin filled in the cavity, and a cooling step, In the middle of this cooling step, the outer peripheral die driving means moves the outer peripheral die in a direction of separating from the fixed die, and the movable die moves away from the fixed die together with the outer die. Molding is performed by a molding cycle of a mold opening process and a take-out process of taking out the disk-shaped recording medium substrate attached to the movable mold side.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described in detail below with reference to the drawings. For example, as shown in FIG. 1, a disk substrate molding die device 10 for molding a synthetic resin disk substrate 1 forming an optical disk includes a fixed mold 11, a movable mold 12, and an outer peripheral mold 21.
It is composed of The fixed mold 11 has a cavity forming portion 13A that defines one main surface 3 of the disk substrate 1 on one side surface. The movable mold 12 is arranged so as to face the fixed mold 11, and can be brought into and out of contact with the fixed mold 11 via guide means and drive means (not shown). The movable mold 12 is provided with a cavity forming portion 13 </ b> B that defines the other main surface 4 of the disk substrate 1 on the side surface facing the fixed mold 11. The fixed mold 11 and the movable mold 12 are attached to the mold attachment portion of the injection molding machine by a structure whose details are omitted.

The outer peripheral die 21 is combined with the movable die 12 as described later in detail, and the outer peripheral portion 7 of the disk substrate 1 is joined.
Is molded. The fixed mold 11, the movable mold 12, and the outer peripheral mold 21 cooperate with each other to form a cavity 13 which is a molding space portion of the disk substrate 1 by a mold clamping operation described later.

The fixed mold 11 has a nozzle located at the center of the cavity 13 for injecting a molten material resin, for example, a transparent polycarbonate resin 5 supplied from the injection molding machine side into the cavity 13 at high pressure. A sprue bush 17 having 16 is assembled. The sprue bush 17 is used for the punch 1 on the movable die 12 side, which will be described later.
The disk substrate 1 is cut and removed by 5
It is provided corresponding to the central cutting area that constitutes the central hole 2.

The fixed mold 11 is a side surface facing the movable mold 12 forming the cavity 13, which is a cavity forming portion 1
3A is configured as a highly accurate smooth surface. A stamper 19 is attached to the cavity forming portion 13A. The stamper 19 is one main surface 3 of the disk substrate 1.
In order to form the information signal recording portion 8 in the cavity 13,
A precise concavo-convex pattern is formed on the main surface facing the.

The stamper 19 transfers and forms, on the one main surface 3 of the disc substrate 1, the pre-grooves forming the pits or recording tracks, which are the concave-convex pattern corresponding to the information signal, by the concave-convex pattern. This stamper 19
It is formed in a disk shape having a center hole in the center. The stamper 19 is a fixed mold 1 in which a high-temperature molten transparent polycarbonate resin 5 is injected into the cavity 13 under high pressure.
Since it is a member attached to the first side, it is attached to the fixed mold 11 by the inner peripheral side stamper holder 18 and the outer peripheral side stamper holder 20.

The stamper holder 18 on the inner peripheral side is the stamper 1
It is formed in an overall cylindrical shape having an outer diameter substantially equal to the inner diameter of the center hole of 9, and is assembled to a substantially cylindrical stamper holder support member 28 fitted and arranged on the outer peripheral portion of the sprue push 17. The inner peripheral side stamper holder 18 and the stamper holder supporting member 28 have the tip surfaces of the disk substrate 1
Forming a cavity corresponding to the inner peripheral part of the fixed mold 11
Has been assembled.

The inner peripheral stamper holder 18 has wedge-shaped engaging portions integrally projecting on the outer peripheral edge thereof. Therefore, in the stamper 19, the inner peripheral portions of the inner peripheral stamper holder 18 are retained by the engaging portions of the inner peripheral stamper holders 18 relatively engaging the inner peripheral wall of the center hole, and the stamper 19 is fixed to the fixed mold 11. It is attached.

The outer peripheral stamper holder 20 is formed in the shape of a ring having a central hole that is slightly larger than the outer diameter of the disk substrate 1 and slightly smaller than the outer diameter of the stamper 19. The outer peripheral side stamper holder 20 is assembled to the fixed mold 11 with a mounting screw. The outer peripheral portion of the stamper 19 is relatively engaged with the wedge-shaped front end portion of the outer peripheral stamper holder 20, so that the outer peripheral portion of the stamper 19 is held by the outer peripheral stamper holder 20 and attached to the fixed mold 11. .

The movable mold 12 is provided at its center with a guide hole 12A having substantially the same diameter as the inner peripheral part of the disk substrate 1 where the information signal recording part 8 is not formed. Into the guide hole 12A, a cylindrical eject member 14 driven by a driving means (not shown) is incorporated so as to be movable back and forth. When the mold opening operation of the disk substrate molding die device 10 to be described later is performed, the eject member 14 projects into the cavity 13 by the driving means and presses the inner peripheral portion of the disk substrate 1, and the disk substrate 1 The protrusion operation of 1 is performed.

The eject member 14 has a center hole 14
A punch 15 driven by a driving unit (not shown)
Is incorporated so that it can move back and forth. The punch 15 projects into the cavity 13 by the driving means and forms the center hole 2 in the semi-cured disk substrate 1 when the compression operation of the disk substrate molding die device 10 described later is performed.

An outer peripheral die drive member 22 which is located on the outer peripheral side and will be described in detail later is assembled to the movable die 12, and an annular outer peripheral die accommodating portion 23 which is open to the side surface on the side of the cavity forming portion 13B. It is recessed all around.
The outer circumference die 21 is stored in the outer circumference die storage section 23 as described later.
Is movably accommodated, and a plurality of air passages 24 are provided on the bottom surface at equal intervals in the circumferential direction. Further, in the outer peripheral die housing portion 23, the inner peripheral wall has an inner peripheral sealing ring 2 for hermetically sealing the outer peripheral die 21 with the outer peripheral die 21 as described later.
A concave groove into which 5 is fitted is provided over the entire circumference.

The outer peripheral die 21 forming the outer peripheral portion 7 of the disc substrate 1 is integrally formed with a die portion 21A having a center hole having an inner diameter equal to the outer diameter of the disc substrate 1 and the bottom surface side of the die portion 21A. It is configured by a member having an overall ring shape including a flange portion 21B formed to project. In the outer peripheral die 21, the flange portion 21B has an outer peripheral die storage portion 23.
The groove has a width dimension substantially equal to the groove width and is accommodated in the outer peripheral die accommodating portion 23 so as to be movable in the axial direction.

The outer peripheral mold 21 is housed in the outer peripheral mold housing part 23 in this way, and the tip of the mold part 21A is the cavity forming part 13B of the movable mold 12 during the mold clamping process described later.
Stamper 1 that is attached to the fixed mold 11 by protruding from
As described above, the cavity 13 of the outer peripheral portion 7 of the disk substrate 1 is formed in opposition to the element 9.

In the outer peripheral die 21, the distance between the tip of the die portion 21A and the stamper 19 is kept constant at an air vent clearance suitable for the transparent polycarbonate resin 5. In the mold part 21A, a holding concave portion 2 which is located at the opening of the inner peripheral wall and forms an outer peripheral convex portion 9 on the outer peripheral portion 7 of the disk substrate 1.
7 are provided. When the movable mold 12 is moved away from the fixed mold 11, which will be described later, the holding recess 27 causes the molded disk substrate 1 to move by the mold release resistance of the outer peripheral protrusions 9. It acts as attached to the side.

The outer peripheral die 21 is provided with a groove on the outer peripheral portion of the flange portion 21B over the entire circumference thereof, and an outer peripheral sealing ring 26 for sealing the outer peripheral die 23 is fitted in the groove. There is. The outer peripheral die 21 has a flange portion 21B formed by the outer peripheral sealing ring 26 and the inner peripheral sealing ring 25 described above.
A closed cylinder space portion 23A is formed between the bottom surface portion and the bottom surface portion of the outer peripheral die storage portion 23. The air passage 24 described above is opened in the cylinder space portion 23A.

As shown in FIG. 7, the air passage 24 is connected to an air compressor 32, supplies compressed air into the cylinder space 23A, and exhausts the supplied compressed air from the cylinder space 23A. To do. The air compressor 32 is controlled by the control unit 30 in response to a molding cycle of the disk substrate 1 by the disk substrate molding die device 10, as described later.

The outer peripheral die driving member 22 is composed of a slightly thick ring-shaped member, and the movable die 12
Is located on the side of the cavity forming portion 13B and is integrally assembled so that the inner peripheral portion thereof slightly protrudes inward of the outer peripheral die accommodating portion 23. The outer peripheral die driving member 22 is provided with a step portion 22A on the inner peripheral portion on the movable die 12 side, which constitutes a concave portion flush with the outer peripheral wall of the outer peripheral die accommodating portion 23.

Therefore, the outer peripheral die driving member 22 has an engaging projection 22B which is slightly inwardly projected along the opening edge of the outer peripheral die accommodating portion 23 by the step portion 22A. The engaging convex portion 22B is the flange portion 21 of the outer peripheral die 21.
It is arranged to face the main surface of B. In addition, the peripheral die driving member 2
2 has the outer peripheral mold 21 by forming the step portion 22A.
Within the range of the step portion 22A, it is possible to project from the cavity forming portion 13B of the movable mold 12 to the fixed mold 11 side.

The step portion 22A is moved in a direction in which the movable mold 12 is separated from the fixed mold 11 by the pressure of the transparent polycarbonate resin 5 injected into the cavity 13 at a high pressure in the injection process described later. In addition, it acts as an escape portion that prevents the outer peripheral die 21 from moving together.

In the disk substrate molding die apparatus 10 configured as described above, as shown in FIG. 2, the fixed die 11 is used.
When the mold clamping step in which the movable mold 12 approaches the is performed, the control signal 31 is sent from the control unit 30 and the air compressor 32 is driven. In the disk substrate molding die device 10, compressed air is supplied from the air compressor 32 to the cylinder space 23A through the air passage 24.

As a result, the outer peripheral die 21 moves to the fixed die 11 side in the outer peripheral die accommodating portion 23 and the flange portion 21.
B hits the outer peripheral side stamper holder 20 and is locked. In this state, the outer peripheral die 21 is opposed to the main surface of the stamper 19 with a space B between the tip portion of the die portion 21A.

Further, in this mold clamped state, the outer peripheral die 21 has a space A (A> A) between the bottom surface of the flange portion 21B and the movable die 12 in the cylinder space portion 23A as shown in FIG. B). Since the outer peripheral die 21 is configured with such an interval A, the die clamping force of the movable die 12 with respect to the fixed die 11 is not directly transmitted, and the stamper 19 is supported by the tip portion of the die portion 21A. Does not scratch or damage the The outer peripheral mold 21 is
A space C (C <A) is formed between the surface of the flange portion 21B and the step portion 22A of the outer peripheral die driving member 22.

As shown in FIG. 3, the disk substrate molding die unit 10 has a cavity 1 formed by a clamped fixed die 11, a movable die 12 and an outer die 21.
The transparent polycarbonate resin 5 melted from the nozzle 16 is injected and filled in the inside of the nozzle 3 at a high pressure. In the mold device 10 for molding a disk substrate, the movable mold 12 is fixed to the fixed mold 11 by filling the cavity 13 with the transparent polycarbonate resin 5.
As a result, as shown in the interval D, the operation is performed in the direction of some separation. The outer peripheral die driving member 22 moves integrally with the movable die 12 and approaches the flange portion 21B of the outer peripheral die 21.

However, in the outer peripheral die 21, as described above, the interval C (C> D) is provided between the flange portion 21B and the step portion 22A of the outer peripheral die driving member 22.
As a result, the outer peripheral die 21 is not moved by the outer peripheral die driving member 22, and the space B is maintained between the die portion 22A and the stamper 19.

In the disk substrate molding die device 10, after the transparent polycarbonate resin 5 is filled in the cavity 13, the movable die 12 is moved slightly closer to the fixed die 11 as shown in FIG. Transparent polycarbonate resin 5
Is compressed. Mold device 10 for molding a disk substrate
As described above, the relatively large distance A is set between the movable mold 12 and the outer peripheral mold 21, whereby the movable mold 12 is largely moved with respect to the fixed mold 11, and the cavity 13 is moved. The transparent polycarbonate resin 5 filled inside is strongly compressed.

Therefore, the disk substrate molding die device 10 can be used even when molding a relatively thin disk substrate 1.
A sufficient compression width can be maintained, and the transferability of the uneven pattern of the stamper 19 can be improved.

On the other hand, the outer peripheral mold 21 is not moved to the fixed mold 11 side together with the movable mold 12 by the above-mentioned interval A, and the above-mentioned mold part 21A and stamper 1 are not moved.
The distance B from 9 is maintained.

In the disk substrate molding die device 10, the punch 15 is driven by a driving means (not shown) when the transparent polycarbonate resin 5 is in a semi-cured state. The punch 15 protrudes into the cavity 13 and the disc substrate 1
A central hole 2 is formed in the.

The disk substrate molding die device 10 is cooled for a predetermined time to cure the transparent polycarbonate resin 5 filled in the cavity 13 to mold the disk substrate 1. Mold device for molding disk substrate 1
0 is a control signal 3 from the control unit 30 during the cooling process.
1 is transmitted, the operation of the air compressor 32 is stopped, and the compressed air supplied to the cylinder space 23A via the air passage 24 is exhausted. As a result, the outer peripheral die 21 moves in the outer peripheral die accommodating portion 23 in the direction away from the fixed die 11, as shown in FIG.
The disk substrate molding die device 10 includes the outer peripheral die 21.
The mold opening operation in which the movable mold 12 is separated from the fixed mold 11 is performed with a slight delay after the moving operation of.

In the outer peripheral die 21, when the movable die 12 moves away from the fixed die 11, the engaging convex portion 22B of the outer peripheral die driving member 22 that integrally operates is relatively engaged with the flange portion 21B. As a result, they are integrally separated from the fixed mold 11. The outer peripheral mold 21 is provided with a holding concave portion 27 in the cavity forming portion of the mold portion 21A, and the outer peripheral convex portion 9 is formed on the outer peripheral portion 7 of the disk substrate 1. The disk substrate 1 attaches the outer peripheral portion 7 to the outer peripheral mold 21 side by the outer peripheral convex portion 9 generating a releasing resistance with respect to the holding concave portion 27. This release resistor is used for the disk substrate 1
The peripheral surface of the outer peripheral portion 7 is larger than the releasing resistance when the entire main surface is released from the stamper 19. Therefore, the disk substrate 1 is fixed to the fixed mold 11 during the mold opening process.
The outer peripheral mold 21 and the movable mold 1 are not attached to the side.
It is attached to the second side and released.

The mold device 10 for molding the disk substrate is shown in FIG.
As shown in FIG. 3, when the movable mold 12 is separated from the fixed mold 11 by the mold opening step, the eject member 14 is projected into the cavity 13 by the driving means (not shown), Press the peripheral area. The disk substrate molding die device 10 includes the eject member 14
Simultaneously with the above operation, a control signal 31 is transmitted from the control unit 30 and compressed air is supplied from the air compressor 32 into the cylinder space 23A via the air passage 24, so that the outer peripheral mold 21 is fixed. Is moved in the direction.

As a result, the molded disc substrate 1
The outer peripheral portion 7 is released from the movable mold 12. Therefore, in the molded disk substrate 1, the main surface 3 and the outer peripheral portion 7 are simultaneously released from the movable mold 12 and the outer peripheral mold 21, and a removal process is performed in which the disk substrate 1 is taken out by a disk substrate removing means (not shown).

The present invention is not limited to the above-described disk substrate molding die device 10. The disk substrate molding die device 10 controls the controller 3 during the die opening process.
The control signal 31 is sent from 0 to drive the air compressor 32, and the compressed air is exhausted from the cylinder space 23A through the air passage 24, thereby moving the outer peripheral die 21 in the movable die direction to move the disc substrate. Although the outer peripheral portion 7 of No. 1 is attached to the movable mold side, the present invention is not limited to this method.

In the following description, the same members as those of the disk substrate molding die device 10 described above are designated by the same reference numerals, and the description of the structure and operation is omitted.

That is, the disk substrate molding die unit 4
0, as shown in FIG. 8, an outer peripheral die drive member 42 is movably incorporated in a drive member housing portion 41 which is located in the outer peripheral portion of the outer peripheral die 21 and is annularly provided in the movable die 12. ing. The outer peripheral die drive member 42 is composed of a ring-shaped member having a slight thickness as a whole. More specifically, the outer peripheral die driving member 42 includes a connecting portion 44 integrally provided so as to project from the piston portion 43 fitted into the driving member housing portion 41 toward the fixed die 11 side, and the connecting portion 44. The engaging portion 45 is bent inward.

The piston portion 43 has a width dimension substantially equal to the width dimension of the drive member accommodating portion 41, and the sealing rings 46A and 46B are fitted to the inner and outer peripheral surfaces thereof, respectively.
A cylinder space 47 is formed between the bottom surface and the bottom surface of the drive member storage portion 41. In the cylinder space 47,
A plurality of air passages 48 are provided at equal intervals in the circumferential direction. These air passages 48 are connected to the air compressor 32 which is the drive source of the outer peripheral die 21.

The inner surface of the tip portion 45A of the engaging portion 45 is opposed to the flange portion 21B of the outer peripheral die 21. The end surface of the tip portion 45A of the engagement portion 45 is opposed to the outer peripheral surface of the outer peripheral side stamper holder 20 on the fixed mold 11 side, and moves along the outer peripheral surface.

In the disk substrate molding die device 40 configured as described above, the control unit 3 is used during the above-mentioned mold opening step.
A control signal 31 is sent from 0 to the air compressor 3
2 is driven. The disk substrate molding die device 40 is
Air in the cylinder space 47 is exhausted from the air compressor 32 through the air passage 48. As a result, the outer peripheral die driving member 42 is moved to the movable die 12 side, and the engaging portion 45 contacts the outer peripheral die 21. Therefore, the outer peripheral die 21 is held on the movable die 12 side. Further, in the disk substrate 1, the outer peripheral mold 21 has the movable mold 12
At the same time, the mold releasing operation is performed integrally with the fixed mold 11, so that the mold is released while maintaining the flatness.

Further, the outer peripheral die driving member 42 shown in FIG.
Is provided in the movable mold 12 in an annular shape, but it is needless to say that it is possible to hold the outer peripheral mold 21 on the movable mold 12 side.

Further, a die device 40 for molding a disk substrate
Then, using the air compressor 32, the outer peripheral mold 21
Although the peripheral die driving member is driven, the means for driving these members is not limited to the air compressor 32, and may be constituted by a hydraulic mechanism, for example.

[0067]

As described in detail above, according to the molding apparatus for molding a disk-shaped recording medium substrate according to the present invention, the outer peripheral mold is driven by the outer peripheral mold driving means from the mold clamping step to the cooling step. Is held in a state of being opposed to the fixed mold during the cooling process, and is controlled so as to move away from the fixed mold prior to the mold opening operation of the movable mold during the cooling process. The recording medium substrate can be peeled from the stamper in a uniform state while maintaining flatness,
A highly accurate disc-shaped recording medium substrate is molded without multiple transfer of the uneven pattern formed on the stamper or optical deflection defects. Further, in the molding die device for molding the disk-shaped recording medium substrate, the compression width of the material resin can be made large during the compression step, and the transferability of the uneven pattern formed on the stamper is improved. Further, the mold device for molding the disk-shaped recording medium substrate can keep the air vent clearance formed between the outer peripheral mold and the stamper constant, so that the optical failure of the disk-shaped recording medium substrate and the outer circumference can be prevented. It is possible to prevent the occurrence of burr on the part.

Further, according to the molding method of the mold apparatus for molding a disk-shaped recording medium substrate of the present invention, the outer peripheral mold is driven by the outer peripheral mold drive means so that the outer peripheral mold is fixed between the mold clamping step and the cooling step. The disk-shaped recording medium substrate is held in a state in which the disk-shaped recording medium substrate is controlled so as to be separated from the fixed mold prior to the mold opening operation of the movable mold during the cooling process. A highly precise disc-shaped recording medium substrate that can be peeled from the stamper while maintaining flatness in a uniform state without multiple transfer of the uneven pattern formed on the stamper or optical deflection defect is formed. Further, in the molding method of the mold device for molding the disk-shaped recording medium substrate, the compression width of the material resin can be made large during the compression step, and the transferability of the concavo-convex pattern formed on the stamper is improved. Further, according to the molding method of the mold device for molding the disk-shaped recording medium substrate, the air vent clearance formed between the outer peripheral mold and the stamper can be kept constant, so that the disk-shaped recording medium substrate It is possible to prevent optical defects and burrs on the outer peripheral portion.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an essential part of a mold device for molding a disk substrate according to the present invention.

FIG. 2 is a longitudinal sectional view of an essential part showing a state of a mold clamping process of the disk substrate molding die device.

FIG. 3 is a longitudinal sectional view of an essential part showing a state of an injection process of the disk substrate molding die device.

FIG. 4 is a longitudinal cross-sectional view of a main part showing a state of a compression process of the disk substrate molding die device.

FIG. 5 is a longitudinal sectional view of an essential part showing a state of a mold opening process of the disk substrate molding die device.

FIG. 6 is a longitudinal sectional view of an essential part showing a state of a substrate taking-out step of the disk substrate molding die device.

FIG. 7 is a structural explanatory view of a peripheral die drive control device.

FIG. 8 is a longitudinal sectional view of an essential part showing a state of a mold opening step of another embodiment of the disk substrate molding die device according to the present invention.

FIG. 9 is a longitudinal sectional view of an essential part showing a state of a mold opening process of a conventional disk substrate molding die device.

FIG. 10 is a vertical cross-sectional view of a main part showing an engaging recess formed in a peripheral die to generate a releasing resistance.

FIG. 11 is a vertical cross-sectional view of a main part of a disk substrate.

[Explanation of symbols]

 1 Disc Substrate 5 Material Resin 10 Mold Device for Molding Disc Substrate 11 Fixed Die 12 Movable Die 13 Cavity 19 Stamper 21 Peripheral Die 21A Cavity Constituent Surface 21B Flange 22 Outer Die Driving Member 22A Step 22B Envelope Convex Part 23 Peripheral mold storage part 23A Cylinder space part 24 Air passages 25, 26 Ring 27 Holding recess 29 Perimeter mold drive member storage part 29A Cylinder part 29B Piston part 29C Connection part 30 Control part 31 Control signal 32 Air compressor 33 Perimeter Mold drive device

Claims (3)

[Claims] 1. A fixed mold having a stamper attached thereto, and a movable mold forming a cavity for forming both sides of a disk-shaped recording medium substrate by being opposed to the fixed mold so as to come into contact with and separate from the fixed mold. An outer peripheral mold for forming an outer peripheral surface of a disk-shaped recording medium substrate by being housed in an outer peripheral mold storage portion provided in the movable mold so as to face the fixed mold so as to be movable, and an outer peripheral mold. And an outer peripheral die driving means for moving the outer peripheral die accommodating portion in the outer peripheral die accommodating portion. A mold apparatus for molding a disk-shaped recording medium substrate, which is held and is separated from a fixed mold prior to a mold opening operation of a movable mold during the cooling process. 2. The outer peripheral die driving means supplies and discharges compressed air to and from the outer peripheral die accommodating portion via an air passage in response to a control signal sent from the control portion in response to a molding cycle, and fixes the outer peripheral die. The mold device for molding a disk-shaped recording medium substrate according to claim 1, wherein the mold device is moved toward and away from the mold. 3. A fixed mold having a stamper attached,
A movable die that forms a cavity that forms both sides of the disk-shaped recording medium substrate by being opposed to the fixed die so that it can be separated from the fixed die, and an outer peripheral die accommodating portion provided in the movable die. A peripheral die that forms the outer peripheral surface of the disk-shaped recording medium substrate by being housed movably opposite to the fixed die, and an outer die drive that moves the outer die to and from the fixed die. A mold device for molding a disk-shaped recording medium substrate including a means is used, and a movable mold and an outer peripheral mold are interlocked with each other with respect to a fixed mold to close the mold to form a cavity. , The injection process of injecting and filling the melted material resin into the cavity formed by this mold clamping process, and moving the movable mold closer to the fixed mold to compress the material resin filled in the cavity. Compression process and cooling A step, an outer peripheral die separating step of moving the outer peripheral die in a direction of separating from the fixed die by the outer peripheral die driving means during the cooling step, and a movable die together with the outer peripheral die with respect to the fixed die. Molding of a disk-shaped recording medium substrate characterized by molding the disk-shaped recording medium substrate by a molding cycle of a mold opening process of separating operation and a take-out process of taking out the disk-shaped recording medium substrate attached to the movable mold side. Method.