JPH0716973B2 - Disc molding method and molding die therefor - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a disk molding method for molding a disk such as an optical disk and a molding die therefor, and particularly to a disk molding method capable of improving the quality of the disk and a method therefor. The present invention relates to a molding die.

BACKGROUND ART In a molding die used for molding a disc such as an optical disc, a stamper on which predetermined information is engraved is generally arranged on a movable mold, and the stamper is fixed to the movable mold on which the stamper is arranged. Disc molding cavities are formed between the molds, and the resin material is injected into the disc molding cavities formed between the fixed mold and the movable mold, whereby the stamper information is obtained. The predetermined disc to which the is transferred is molded.

And, in such a molding die, conventionally,
During the mold opening operation, the disk molded in the cavity is retained and held on the movable mold side based on the adhesive force with the stamper. In the prior art, the disk was taken out of the movable mold by a predetermined ejector mechanism.

Thus, a disc formed by using such a conventional disc molding die is apt to cause a stamper information transfer defect that looks like stains or smears, which is one of the causes of deterioration of the disc quality. Was becoming.

(Problem to be Solved) The present invention has been made in view of such circumstances, and an object of the present invention is to suppress or reduce the occurrence of imperfect transfer of stamper information such as stains and smear, and It is an object of the present invention to provide a disk molding method capable of improving quality and a molding die therefor.

(Solution) In order to solve such a problem, in the present invention, a stamper is arranged on a cavity forming surface of either one of a movable mold and a fixed mold, and is formed between the molds. In the disk molding method, in which a resin material is injected into the disk molding cavity to mold the disk to which the information of the stamper is transferred, the disk molded in the cavity is moved to the movable mold. When the mold is opened from the fixed mold, the disc is separated from the mold on the side where the stamper is arranged by holding it on the mold on the side where the stamper is not arranged, and the stamper information of the disc is transferred. In order to effectively realize such a method, a disk molding method characterized in that the side surface is exposed to the atmosphere is provided. While the stamper is disposed on the cavity forming surface of either the movable mold or the fixed mold, the resin material is injected into the disk molding cavity formed between the molds, so that the information of the stamper can be obtained. In a disk molding die adapted to mold a disk to which is transferred, the disk molded in the cavity is placed on the non-disposed side of the stamper when the movable mold and the fixed mold are opened. A holding means for holding the die is provided, and by opening the movable die from the fixed die, the disc formed in the cavity is retained / held in the die on the side where the stamper is not disposed. Of.

(Operation) In the disk molding technique according to the present invention as described above,
During the mold opening operation of the movable mold from the fixed mold, the disk molded in the cavity is left and held in the mold on the side where the stamper is not installed, and after the mold is opened, the disk is not installed with the stamper. As a result of being released from the die on the side of the side, as a result, the disc is retained and held in the die on the side where the stamper is placed during the die opening operation, compared to the case of forming with a conventional die. The imperfect transfer of stamper information, such as stains and haze, that occurs in the first place can be greatly suppressed or reduced.

As described above, the disk molded by the molding die according to the present invention can suppress or reduce the occurrence of imperfect transfer of stamper information such as stains and mist rather than the disk molded by the conventional molding die. The reason is that when the mold is opened, the surface of the disc that is exposed to the atmosphere is different,
It is considered that this is because the state of contraction of the disk or the state of generation of internal stress at the time of release from the stamper is different.

(Examples) In order to more specifically clarify the present invention,
An embodiment will be described in detail with reference to the drawings.

First, FIG. 1 shows a main part of a disk mold according to the present invention. Therein, 10 is a mirror surface plate of the fixed mold 12, which forms a disc-shaped disk molding cavity 18 between the mirror surface plate 16 of the movable mold 14 and the rear plate 20.
It is attached to the fixed mold main body 22 via the fixed mold main body 22 via the fixed mold main body 22.

The mirror plate 10 of the fixed mold 12 has an air passage forming member that penetrates the mirror plate 10 and the back plate 20 concentrically with the cavity.
24 is provided, and between the outer peripheral surface of the air passage forming member 24 and the inner peripheral surface of the mirror surface plate 10, an annular air passage 26 with a minute clearance communicated with the cavity 18 is formed. There is. And here, this air passage 26
Is to be selectively connected to a vacuum suction device and an air pressure supply device (not shown) through an air passage 28 provided through the fixed mold body 22.
As will be described later, during the mold opening operation of the movable mold 14 from the fixed mold 12 after the disk molding, the suction operation of air is performed through the air passage 26, while the disk after the mold opening is performed. Such air passage when releasing
A predetermined amount of compressed air can be blown from 26.

Further, in the air passage forming member 24, a through hole 30 penetrating the air passage forming member 24 and the fixed mold body 22 in the axial direction is formed, and the through hole 30 is fitted into the through hole 30.
A sprue bush 32 having a double cylinder structure provided with a cooling water passage is arranged. Then, as described later, the resin material injected from the nozzle 29 of the injection device is guided to the cavity 18 through the sprue bush 32 during the molding of the disc.

On the other hand, the mirror plate 16 of the movable mold 14 that forms the cavity 18 with the mirror plate 10 of the fixed mold 12 is attached to the movable mold body 36 via the back plate 34, and the movable mold is It is adapted to be attached to the movable plate of the mold clamping device via the mold body 36.

On the cavity forming surface of the mirror surface plate 16 of the movable mold 14, an outer stamper retainer 38 disposed on the outer peripheral portion of the mirror surface plate 16,
A stamper 42, which is held by an inner stamper retainer 40 that penetrates through the mirror plate 16 and the back plate 34, and in which predetermined information is engraved, is arranged and molded in the cavity 18. The information engraved on the stamper 42 can be transferred onto the disc.

Also, the inner stamper retainer that holds the inner peripheral portion of the stamper 42
Inside the 40, the inside stamper retainer 40 is
An air passage forming member 44 is provided so as to pass through concentrically with 18, and between the outer peripheral surface of the air passage forming member 44 and the inner peripheral surface of the inner stamper retainer 40, the fixed mold 12 side is provided. Air passage
An annular air passage 46 having a minute clearance similar to that of 26 is formed. And here, in the air passage 46,
An air pressure supply device is configured to be connected via an air passage 48 provided through the movable mold main body 36, so that, as will be described later, from the fixed mold 12 of the movable mold 14. During the mold opening operation, predetermined compressed air is blown out from the air passage 46 toward the cavity 18.

Further, a guide sleeve 50 is provided inside the air passage forming member 44 so as to penetrate the air passage forming member 44. The guide sleeve 50 penetrates the guide sleeve 50 concentrically with the cavity 18 so as to be movable in the axial direction, and is provided with a punch cutter 52 having a double cylinder structure provided with a cooling water passage. An ejector pin 54 is provided so as to penetrate the central portion so as to be movable in the axial direction.

Here, the punch cutter 52 is designed to be moved a predetermined distance in the axial direction by a driving means such as a double-acting cylinder (not shown) provided on the base end side thereof, and like the conventional forming die, the pulling-in is performed. At the position, an annular gate is formed between the sprue bush 32 and the sprue bush 32, and at the protruding position, the gate is made to protrude into the through hole 30 on the fixed mold 12 side and is molded in the cavity 18. It is designed to punch out the central hole of the disc.

Further, the ejector pin 54 is also adapted to be moved by a predetermined drive means (not shown) in the axial direction by a predetermined distance like the conventional molding die, and as will be described later, after the die opening operation of the die, By projecting to the tip side, that is, the fixed mold 12 side, and operated, the resin in the punched part of the central hole punched from the disc is released from the movable mold 14.

By the way, in such a molding die, the molding of the disc is performed as follows.

That is, when molding a disc using such a molding die, first, as shown in FIG. 1, in a state where the punch cutter 52 and the ejector pin 54 are pulled in to the respective base end sides thereof, 14 is fitted to the fixed mold 12. Then, in this mold matching state, the nozzle 29 of the injection device is made to touch the sprue bush 32,
Through both the sprue bush 32 and the gate between the sprue bush 32 and the punch cutter 52, the mirror plate 1 of both molds 1
A resin material is injected into the disk molding cavity 18 formed between 0 and 16.

When the filling operation of the resin material into the cavity 18 is completed,
After the elapse of a predetermined cooling / solidifying period, the punch cutter 52 is projected and actuated to form the disk A formed in the cavity 18.
The central hole 56 (see FIG. 2) of the is punched out. Then, after punching out the central hole 56, the movable mold 14 is separated from the fixed mold 12 by the retracting operation of the movable plate of the mold clamping device. That is, the mold opening operation is performed. Incidentally, the projecting operation of the punch cutter 52 is allowed here by the movement of the sprue bush 32 to the right in FIG. 1, as is well known.

By the way, when the mold opening operation of the mold by the backward movement of the movable plate of the mold clamping device is started, at the same time or immediately before that, the air passage 46 on the movable mold 14 side is compressed by the air pressure through the air passage 48. It is connected to a supply device and a predetermined compressed air is blown out from the air passage 46 toward the cavity 18 side. At the same time, the air passage on the fixed mold 12 side
26 is connected to the vacuum suction device via the air passage 28, and the suction operation of air through the air passage 26 is started.
As a result, the disk A molded in the cavity is separated from the movable mold 14, that is, the stamper 42, by the compressed air blown from the air passage 46 on the movable mold 14 side, while the fixed mold 12 is released. By the suction operation of air through the side air passage 26, it is adsorbed to the fixed mold 12 side. That is, when the movable mold 14 is opened from the fixed mold 12, the disc A molded in the cavity 18 is disengaged from the movable mold 14 side as shown in FIG. In a state where the surface on the side where the stamper information is transferred is exposed to the atmosphere, the fixed mold 12 that is the mold on the side where the stamper is not provided is used.
It is retained and retained on the side.

As shown in FIG. 2, the resin B in the central hole punched out from the disk A is retained and held on the movable mold 14 side as in the conventional molding die.

Further, as is clear from the above description, in this embodiment,
The holding means is composed of the air passages 26, 28 formed on the fixed mold 12 side and a vacuum suction device connected to the air passages 26, 28.

As shown in FIG. 2, when the movable mold 14 is separated from the fixed mold 12 by a certain distance and the mold opening operation is completed, the ejector pin 54 is projected and actuated to move the resin B at the punched-out portion of the central hole. It is released from the mold and removed. And
After removing the resin B in the punched part of the central hole, the fixed mold 12
The disk A held at is taken out by a predetermined take-out device. This completes a series of disk molding operations.

When the disk A is taken out from the fixed mold 12, the air passage 26 is usually connected to an air pressure supply device in order to assist the separation (release) of the disk A from the fixed mold 12. The compressed air is blown out from the air passage 26.

As described above, according to the disk molding die of this embodiment, when the movable mold 14 is opened from the fixed mold 12, the disk A molded in the cavity 18 is located on the non-stamper side. The disc A is retained and held on the fixed die 12 side as a die, and after the die opening operation is completed, the disc A is taken out from the fixed die 12 by a predetermined take-out device. As a result, as compared with a disc formed by using a conventional forming die that holds the disc in a die on the side where the stamper is disposed, stains or smear-like transfer defects of the stamper information are significantly suppressed or reduced. As a result, the quality of the disc A is significantly improved.

Incidentally, FIGS. 3 and 4 show a disc A formed by a molding die according to the present embodiment in which a die on the side where the stamper is not disposed holds the disc and a die on the side where the stamper is disposed hold the disc. An example of the generation state of a transfer defect C of stamper information such as a stain or a smear is shown for each of the disk A formed by the conventional forming die which is pressed. It is recognized that when the disc is molded by the molding die according to (1), the defect C of transfer of stamper information such as stains or mist that occurs on the disc can be significantly reduced as compared with the case where the disc is molded by the conventional molding die.

As described above, one embodiment of the present invention has been described in detail, but this is a literal example, and the present invention is not limited to such a specific example, within a range not departing from the gist thereof,
It goes without saying that the present invention can be carried out in a mode in which various changes, corrections and improvements are made.

For example, the guide sleeve 50 in the above embodiment is provided so as to be movable in the axial direction, and
1 is provided with a projecting actuating means for projecting and operating a predetermined amount on the right side, and the guide sleeve 50 relative to the tip end thereof as the movable die 12 is detached from the fixed die 14 (die opening operation). The guide sleeve 50 allows the disc A to be detached from the movable mold 12 so as to be ejected to the side.
It is also possible to independently perform the projecting operation of the movable sleeve, and to cooperate with both the projecting operation of the guide sleeve 50 and the blowing operation of the air from the air passage 46 in the above embodiment. It is also possible to separate the disc A from the mold 14. It should be noted that such detaching means can be omitted depending on the situation.

In addition, a member that defines the outer edge of the cavity 18 is fixed to the mold.
Provided on the 12 side, the inner peripheral surface of the outer edge defining member,
The fixed mold 12 is formed on the side of the fixed mold 12, and the disk A is fixed on the basis of the engagement between the tapered surface of the outer edge defining member and the outer peripheral edge of the disk A defined by the tapered surface.
It is also possible to allow the 12 side to remain and hold.
However, in this case, the outer edge defining member that defines the outer edge of the cavity 18 constitutes the holding means. The disk A is held on the fixed mold 12 side by both the engagement of the outer edge defining member with the outer peripheral edge of the disk A and the suction operation of air through the air passage 26 in the above-described embodiment. Of course, it is possible.

Further, in the above-mentioned embodiment, since the stamper is arranged on the movable mold side, the disc is made to remain / hold on the fixed mold side by the holding means when the mold is opened. In the molding die disposed on the die side, the disc is retained and held on the movable die side by the holding means when the die is opened. Even in this case, it is possible to significantly suppress or reduce the imperfect transfer of stamper information such as stains or mist that occurs on the disc.

(Effects of the Invention) As is apparent from the above description, in the disc molding method and the disc molding die according to the present invention, molding is performed in the cavity during the mold opening operation between the movable mold and the fixed mold. The disc remains in the mold on the non-disposition side of the stamper.
Since it is designed to be held, stains and smear-like stamper information transfer defects that occur on the molded disk are effectively suppressed or reduced, which significantly improves the quality of the disk molded product. It was decided.

[Brief description of drawings]

1 is a sectional view showing a main part of a forming die according to the present invention, and FIG. 2 is a sectional view corresponding to FIG. 1 showing different operating states of the forming die of FIG. FIG. 3 is an explanatory diagram showing an example of imperfect transfer of stamper information such as stains and mist on a disc molded by a molding die according to the present invention, and FIG. 4 shows a disk molded by a conventional molding die. It is a figure corresponding to FIG. 12: Fixed mold, 14: Movable mold 18: Disc molding cavity 24,44: Air passage forming member 26,28,46,48: Air passage 32: Sprue bush 42: Stamper, 50: Guide sleeve 52: Punch cutter

Claims (2)

[Claims] 1. A stamper is disposed on a cavity forming surface of either a movable mold or a fixed mold, and a resin material is injected into a disk molding cavity formed between the molds, whereby In a disk molding method for molding a disk to which information of a stamper is transferred, the stamper is not disposed when the disk molded in the cavity is opened between the movable mold and the fixed mold. The disc is separated from the die on the side where the stamper is provided by holding the disc in the die on the side, and the surface of the disc to which the stamper information is transferred is exposed to the atmosphere. Disc molding method. 2. A stamper is provided on a cavity forming surface of either a movable mold or a fixed mold, and a resin material is injected into a disk molding cavity formed between the molds, whereby In a disk molding die for molding a disk to which information of a stamper is transferred, the disk molded in the cavity is unaligned with the stamper when the movable mold and the fixed mold are opened. A holding means for holding the die on the installation side is provided, and when the movable die is opened from the fixed die, the disc formed in the cavity remains on the die on the side where the stamper is not disposed.
A disk molding die characterized in that it can be held.