JP2006024260A - Disc substrate manufacturing method and disc substrate ejecting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reliably take out a disk substrate from a molding body without deteriorating optical characteristics and mechanical characteristics of the disk substrate. <P>SOLUTION: The method of manufacturingthe disk substrate comprises: a molding step for injection molding the disk substrate 3 using a molding metal mold 5; a releasing step for releasing the disk substrate 3 from the molding metal mold 5; and a takeout step for holding the disk substrate 3 by using a vacuum suction pad 22 whose temperature is adjusted and a mechanical clamp part 23 to take out the disk substrate 3 from the molding metal mold 5. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a disk substrate manufacturing method and a disk substrate take-out apparatus for manufacturing a disk substrate such as an optical disk or a magneto-optical disk by injection molding.

  A conventional optical disk substrate injection molding method will be described with reference to FIGS. FIG. 7 is a cross-sectional view showing an injection molding machine, and FIG. 8 is a plan view showing a disk substrate take-out device from a movable mold in FIG.

  In general, in a conventional disk substrate injection molding method, as shown in FIG. 7, a stamper 113 for transferring a desired uneven pattern to the disk substrate 103 is attached to a cavity of a molding die. This is a method of molding the disk substrate 103 by injecting, filling, and compressing the material of the disk substrate 103 such as a molten resin material into the cavity by the nozzle 108.

  After opening the movable side mold 112 away from the fixed side mold 111, as shown in FIG. 8, the transport arm 131 is rotated by the motor 132, so that the take-out device 107 is placed in the molding die. The sprue 104 and the disk substrate 103 which are made to enter and separated from the movable mold 112 by the ejector 119 are held with the sprue 104 held by the sprue chuck 121 of the take-out device 107, and the disk substrate 103 is held by the vacuum suction pad 122. By sucking, the molded disk substrate 103 is held, and the conveying arm 131 is rotated by the motor 132 to be taken out from the molding die.

  However, in this method, the vacuum suction pad 122 having a temperature substantially close to room temperature comes into contact with the disk substrate 103 which is a high-temperature molded product. For this reason, when the vacuum suction pad 122 whose temperature is lower than that of the disk substrate 103 is in contact with the disk substrate 103, local thermal shrinkage occurs in the formed disk substrate 103. It can be a cause. In addition, there is a case where the holding of the disk substrate 103 may fail due to deterioration of the vacuum suction pad 122 or usage conditions, and there is a problem that the reliability of the holding operation is poor.

Further, as a conventional disk substrate molding apparatus provided with such a vacuum suction pad, a vacuum suction in which an inner peripheral side protruding portion and an outer peripheral side protruding portion that respectively contact the inner peripheral side and the outer peripheral side of the disk substrate are formed. A configuration is disclosed that includes a pad and prevents the disk substrate from being deformed, such as warping, when the disk substrate is taken out of the molding die (see Patent Document 1).
Japanese Patent Laid-Open No. 2002-230851

  As described above, in the conventional disk substrate manufacturing method, when the released disk substrate is held by the vacuum suction pad, it is difficult to securely hold the disk substrate by the vacuum suction pad, and the disk substrate is accidentally dropped. May cause problems.

  In addition, when holding the disk substrate by the vacuum suction pad, thermal shrinkage occurs in the molded disk substrate by contacting the vacuum suction pad at room temperature and the hot disk substrate shortly after molding, There is a problem that it becomes a serious defect such as unevenness of birefringence, warpage, and distortion.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a disk substrate manufacturing method and a disk substrate take-out device that can be reliably taken out from a molding die without deteriorating the optical characteristics and mechanical characteristics of the disk substrate. .

  In order to achieve the above-described object, a disk substrate manufacturing method according to the present invention includes a molding step of injection molding a disk substrate with a molding die, a mold release step of releasing the disk substrate from the molding die, And a take-out step of holding the disk substrate by the holding means whose temperature is controlled and taking it out of the molding die.

  According to the above-described disk substrate manufacturing method of the present invention, the disk substrate is held by the temperature-controlled holding means, thereby causing local thermal shrinkage on the disk substrate, thereby providing optical characteristics and mechanical characteristics. The disk substrate can be taken out from the molding die without deteriorating.

  In the take-out process of the disk substrate manufacturing method according to the present invention, it is preferable that the disk substrate is mechanically held by the holding means. As a result, the reliability of the holding operation of the disc substrate by the holding means is improved, so that the disc substrate can be reliably taken out from the molding die without dropping the disc substrate.

  Further, in the take-out process of the disk substrate manufacturing method according to the present invention, other holding means for holding the disk substrate with negative pressure may be further used. As a result, the disk substrate can be more securely held and removed from the molding die.

  The disk substrate take-out apparatus according to the present invention includes a holding means for holding the disk substrate formed by the molding die, a driving means for moving the holding means relative to the molding die, and a holding means. Temperature control means for controlling the temperature.

  As described above, according to the present invention, the disk substrate can be removed from the molding die without degrading the optical characteristics and mechanical characteristics of the disk substrate by holding and taking out the disk substrate by the temperature-controlled holding means. The substrate can be taken out.

  Hereinafter, specific embodiments according to the present invention will be described with reference to the drawings.

(First embodiment)
The disk substrate take-out device of the first embodiment will be described with reference to FIGS.

  FIG. 1 is a cross-sectional view schematically showing the entire injection molding machine of the present embodiment. FIG. 2 is a perspective view schematically showing a temperature-controlled mechanical clamp portion in the disk substrate take-out device provided in the injection molding machine.

  The injection molding machine of this embodiment is an injection molding machine for molding a disk substrate such as an optical disk or a magneto-optical disk.

  As shown in FIG. 1, an injection molding machine according to this embodiment includes a molding die 5 for molding a disk substrate 3 and a nozzle for injecting and filling a resin material into the molding die 5. 8 and an ejection device 7 for taking out the molded disk substrate 3 from the molding die 5.

  The molding die 5 is provided in the fixed side mold 11 and the movable side die 12 constituting a cavity (not shown) for molding the disk substrate 3 and a desired uneven pattern. Are stamped on the disk substrate 3 and platens 15 and 16 for supporting the fixed side mold 11 and the movable side mold 12 are provided. Further, the movable mold 12 is provided with a cut punch 17 for performing gate cutting of the central hole of the disk substrate 3, and an ejector pin 18 and an ejector 19 for releasing the molded disk substrate 3 from the cavity. It has been.

  As shown in FIG. 1, the take-out device 7 is fixedly disposed on a platen 15 that supports a fixed mold 11, and includes a sprue chuck 21 that holds the sprue 4 of the molded disk substrate 3, and a disk substrate. A vacuum suction pad 22 that sucks and holds 3, a mechanical clamp portion 23 that mechanically holds the disk substrate 3, and these sprue chuck 21, vacuum suction pad 22, and mechanical clamp portion 23 with respect to the molding die 5. And a temperature control unit (not shown) for controlling the temperatures of the vacuum suction pad 22 and the mechanical clamp unit 23, respectively.

  The sprue chuck 21 is disposed at the center of the vacuum suction pad 22 and is supported by the second hand 31 b of the transfer arm 31.

  Although not shown, the vacuum suction pad 22 has a plurality of suction holes communicated with the compressor through suction pipes, and generates a negative pressure in these suction holes, thereby near the periphery of the center hole of the disk substrate 3. Adsorb and hold. Although not shown, a heater electrically connected to the temperature control unit is provided in the vicinity of the vacuum suction pad 22, and the temperature of the vacuum suction pad 22 is controlled by the temperature control unit. However, the temperature is maintained by being heated to a temperature substantially equal to the temperature of the disk substrate 3 when the disk substrate 3 is held.

  The mechanical clamp unit 23 includes a pair of clamp members 27 that hold the outer peripheral portion of the disk substrate 3, and a heater 26 that heats and holds the clamp members 27. The heater 26 is electrically connected to the temperature control unit, and is controlled by the temperature control unit so that the clamp member 27 is heated to a temperature substantially equal to the temperature of the disk substrate 3 when holding the disk substrate 3. Being kept warm.

  The drive unit 24 includes a transport arm 31 for transporting the sprue chuck 21, the vacuum suction pad 22, and the mechanical clamp unit 23, and a motor 32 for rotating the transport arm 31 in the direction of arrow a in FIG. .

  The transport arm 31 is provided with a rotation shaft connected to the motor 32 at the base end portion, and is supported so as to be rotatable in the direction of arrow a via the rotation shaft. The transport arm 31 has a first hand 31 a that supports the mechanical clamp unit 23 and a second hand 31 b that supports the sprue chuck 21 and the vacuum suction pad 22 at the tip.

  Regarding the injection molding machine configured as described above, an operation in which the take-out device 7 takes out the disk substrate 3 from the molding die 5 will be described.

  As shown in FIG. 1, the metered, melted, and kneaded resin material is injected and filled from the nozzle 8 into the cavity of the molding die 5, and then gate cut is performed by the cut punch 17, and holding pressure and compression pressure are obtained. The movable mold 12 is separated from the fixed mold 11 and opened. After opening the mold, in the movable mold 12, the sprue 4 is ejected by the ejector pins 18, and at the same time, the disk substrate 3 is ejected from the cavity of the movable mold 12 by the ejector 19, thereby releasing the disk substrate 3. Is done.

  Similar to the operation of the conventional take-out device 107 shown in FIG. 8, when the mold 5 is opened, the transport arm 31 is rotated by the motor 32, and the fixed mold 11 and the movable mold 12 are moved. By inserting the take-out device 7 between them, the sprue 4 protruding from the movable mold 12 is received and held by the sprue chuck 21 and the outer periphery of the disk substrate 3 protruding from the movable mold 12 is retained. It is received and held by the clamp member 27.

  FIG. 2 shows a state in which the outer peripheral portion of the disk substrate is held by the clamp member. The clamp member 27 whose temperature has been adjusted is driven so as to sandwich the disk substrate 3 therebetween, and holds the outer periphery of the disk substrate 3. When holding the disk substrate 3, the vacuum suction pad 22 adjusted to a constant temperature is used together with the clamp member 27.

  The mechanical clamp 23 for mechanically holding the disk substrate 3 by adjusting the temperature is not limited to the above-described configuration. Further, the temperature of the clamp member 27 whose temperature has been adjusted, the timing of holding the disc substrate 3 after molding, the moving speed of the clamp member 27 when holding, the holding force, etc. are arbitrarily adjusted. Further, it is desirable that the holding force applied to the disk substrate 3 when the mechanical clamp 23 holds the outer periphery of the disk substrate 3 is set as small as possible.

  Using the injection molding machine of the first embodiment configured as described above, injection molding for molding the disk substrate 3 having a thickness of about 0.6 mm and an outer diameter of about 86 mm was performed. As a material for the disk substrate 3, polycarbonate resin was used. As shown in FIG. 1, after the metered, melted, and kneaded resin material is injected and filled into the cavity of the molding die 5 from the nozzle 8, the gate is cut by the cut punch 17, and the holding pressure and the compression pressure are set. In addition, the mold was opened by cooling and separating the movable mold 12 from the fixed mold 11.

  After opening the mold, the sprue 4 is ejected by the ejector pin 18 at the movable side mold 12 and at the same time the disk substrate 3 is ejected by the ejector 19 to be released from the mold, similarly to the operation of the conventional take-out device 107 shown in FIG. The transfer arm 31 was inserted between the fixed mold 11 and the movable mold 12 when the mold was opened. Subsequently, the sprue 4 is received and held by the sprue chuck 21, and the outer periphery of the disk substrate 3 is received by the clamp member 27 whose temperature is adjusted to a constant temperature of about 80 ° C. which is substantially equal to the temperature of the disk substrate 3 by the heater 26. Held. At this time, the periphery of the center hole of the disk substrate 3 was also sucked and held by the vacuum suction pad 22.

  As described above, as shown in FIG. 2, the outer periphery of the disk substrate 3 is sandwiched and held by the temperature-adjusted clamp member 27 using the mechanical clamp portion 23 and the vacuum suction pad 22 to release the disc. When the holding operation test for holding the substrate 3 was performed about 50 times, the success rate of taking out the molded disk substrate 3 was 100%.

  Further, by using the clamp member 27 whose temperature is adjusted to a constant temperature of about 80 ° C., it is possible to prevent local thermal contraction of the disk substrate 3 when the disk substrate 3 is held. The obtained disk substrate 3 had a birefringence phase difference non-uniformity of 10 nm or less with respect to the circumferential direction, and had a maximum surface shake and a shake amount of 50 μm or less.

  The birefringence of the disk substrate 3 was measured by a double pass using an automatic birefringence measuring apparatus (manufactured by TOYO.AT: B-6H). The mechanical properties were measured using an optical disk mechanical property measuring device (manufactured by Ono Sokki Co., Ltd .: LM1200). Further, the resin material forming the disk substrate 3, the stamper to be used, the molding machine, etc. may be freely selected.

  As described above, according to the take-out device 7, the optical characteristics of the disk substrate 3 formed by providing the mechanical clamp unit 23 and the vacuum suction pad controlled to a temperature substantially equal to the temperature of the disk substrate 3 to be held and It can be reliably removed from the molding die 5 without deteriorating mechanical properties.

  Further, according to this take-out device 7, the reliability of the holding operation of the disk substrate 3 can be improved by mechanically holding the outer peripheral portion of the disk substrate 3 by the mechanical clamp portion 23.

(Second Embodiment)
Next, another take-out device provided in the injection molding machine according to the second embodiment will be described with reference to FIGS. Since the other take-out apparatus has the same configuration as the take-out apparatus included in the injection molding machine according to the first embodiment described above except for the mechanical clamp portion, the same members are denoted by the same reference numerals and described. Omitted.

  FIG. 3 is a sectional view showing a state in which the sprue chuck is positioned in the center hole of the disk substrate. On the other hand, FIG. 4 is a sectional view showing a state in which the clamp member is moved to a position corresponding to the center hole of the disk substrate. FIG. 5 is a plan view showing a mechanical clamp unit, a vacuum suction pad and a sprue chuck provided at the tip of the transfer arm. Further, FIG. 6 is a perspective view showing a clamp member of the mechanical clamp portion.

  As shown in FIG. 3, the take-out device 35 according to this embodiment includes a vacuum suction pad 36 for sucking and holding the vicinity of the center hole of the disk substrate 3, and a disk inserted into the center hole of the disk substrate 3. And a mechanical clamp portion 37 for mechanically holding the inner peripheral portion of the substrate 3.

  As shown in FIGS. 3 and 5, the vacuum suction pad 36 is formed in an annular shape, and is supported by the distal end portion of the first hand 31 a of the transport arm 31. In addition, the sprue chuck 21 is supported on the transport arm 31 by the second hand 31b.

  Although not shown, a heater for heating the vacuum suction pad 36 is provided in the vicinity of the vacuum suction pad 36, and the temperature of the vacuum suction pad 36 is controlled by the temperature controller. It is kept at a temperature substantially equal to the temperature of the disk substrate 3.

  The mechanical clamp portion 37 is supported on the distal end portion of the first hand 31a of the transport arm 31 so as to be positioned at the center of the vacuum suction pad. As shown in FIGS. 6A and 6B, the mechanical clamp portion 37 has a clamp member 38 formed of a so-called split pin-shaped holding claw that is divided into four. The clamp member 38 is inserted into the center hole of the disc substrate 3 in a closed state as shown in FIG. 6A, and after insertion, the disc substrate 3 is opened in an open state as shown in FIG. 6B. The inner periphery of the disk substrate 3 is mechanically held.

  As shown in FIG. 4, the mechanical clamp unit 37 is provided with a heater 26 for heating the clamp member 38, and the temperature of the clamp member 38 is controlled by the heater 26 being controlled by the temperature control unit. It is kept at a temperature substantially equal to the temperature of the disk substrate 3.

  According to the take-out device 35 according to the present embodiment, since the vacuum suction pad 36 and the mechanical clamp portion 37 that are temperature-adjusted are arranged close to each other, the vacuum suction pad 36 and the mechanical clamp portion 37 are common. The temperature may be controlled by a heater, and the configuration can be simplified.

  Regarding the injection molding machine configured as described above, the operation of the take-out device 35 to take out the disk substrate 3 from the molding die 5 will be briefly described.

  After the mold opening, the transfer arm 31 of the take-out device 35 shown in FIG. 5 is inserted between the fixed mold 11 and the movable mold 12 in the same manner as the conventional take-out apparatus 107 shown in FIG.

  First, as shown in FIG. 3, only the sprue 4 protrudes toward the cavity by the ejector pin 18, the sprue 4 is received and held by the sprue chuck 21, and the transport arm 31 is parallel to the main surface of the disk substrate 3 by the motor 32. The sprue chuck 21 is moved to a position where it does not interfere with the molding die 5.

  Next, the transport arm 31 is rotated by the motor 32, and the clamp member 38, the temperature of which has been adjusted by the heater 26, is moved to a position corresponding to the center hole of the disk substrate 3. As shown in FIG. The clamp member 27 whose temperature is adjusted is inserted into the central hole 3 and released together with the air blower and the ejector 19. At the same time, the central hole of the disk substrate 3 is held by the clamp member 38.

  For example, as shown in FIG. 6, the clamp member 38 inserted into the center hole of the disk substrate 3 spreads the holding claws closed at the time of insertion when the mold is taken out after the mold release, so that the center hole of the disk substrate 3 is expanded. The disk substrate 3 is held by engaging with.

  Note that the temperature-controlled clamp member 38 is not limited to the above-described configuration. Further, the temperature of the clamp member 38 whose temperature has been adjusted, and the timing at which the disk substrate 3 is held after molding, the moving speed of the clamp member 38 at the time of holding, the holding force, and the like are arbitrarily adjusted. It is desirable that the holding force applied to the disk substrate 3 when the mechanical clamp unit 37 holds the disk substrate 3 is as small as possible.

  Using the injection molding machine of the second embodiment configured as described above, injection molding was performed to mold the disk substrate 3 having a thickness of about 0.6 mm and an outer diameter of about 86 mm. As a material for the disk substrate 3, polycarbonate resin was used. As shown in FIG. 3, after the metered, melted and kneaded resin material is injected and filled into the cavity of the molding die 5 from the nozzle 8, the gate is cut by the cut punch 17, and the holding pressure and the compression pressure are set. In addition, it was cooled and opened.

  After the mold opening, the take-out device 7 shown in FIG. 5 is inserted between the fixed-side mold 11 and the movable-side mold 12 in the same manner as the operation of the conventional take-out apparatus 107 shown in FIG. As shown in FIG. 3, only the sprue 4 is protruded from the center hole of the disk substrate 3 by the ejector pin 18, and the sprue 4 is received and held by the sprue chuck 21 shown in FIG. The sprue chuck 21 was moved to a position where it does not interfere with the molding die 5 by rotating in the direction of arrow a parallel to the main surface of the substrate 3.

  Next, the clamp member 38 shown in FIG. 6 whose temperature is adjusted to a constant temperature of about 90 ° C. by the heater 26 is moved to a predetermined position, and the clamp member 38 is placed in the center hole of the disk substrate 3 as shown in FIG. The inner periphery of the disk substrate 3 was held by being inserted and released together with the air blower and the ejector 19. In addition, when such a holding operation test was performed about 50 times, the success rate of taking out the molded disk substrate 3 was 100%.

  In addition, by using the clamp member 38 whose temperature is adjusted to a constant temperature of about 90 ° C., when the disk substrate 3 is held by the clamp member 38, the occurrence of local heat shrinkage on the disk substrate 3 can be prevented. I was able to. The obtained disk substrate 3 had a birefringence phase difference non-uniformity of 10 nm or less with respect to the circumferential direction, and a maximum surface shake and a shake amount of 40 μm or less.

  The birefringence of the disk substrate 3 was measured by a double pass using an automatic birefringence measuring apparatus (manufactured by TOYO.AT: B-6H). The mechanical properties were measured using an optical disk mechanical property measuring device (manufactured by Ono Sokki Co., Ltd .: LM1200).

  In the take-out devices 7 and 35 of the above-described embodiments, the mechanical clamp portions 23 and 37 that mechanically hold the disk substrate 3 and the vacuum suction pads 22 and 36 that hold the disk substrate 3 with negative pressure are used in combination. As a result, the reliability of the holding operation of the disk substrate 3 has been improved, but it is of course possible to hold the disk substrate 3 only by the mechanical clamp portions 23 and 37 if necessary. is there.

  Although not shown, the take-out device according to the present invention includes a mechanical clamp portion 23 that holds the outer peripheral portion of the disc substrate 3 and a mechanical clamp portion 37 that is inserted into the center hole of the disc substrate 3 and holds the inner peripheral portion. And may be used together.

It is sectional drawing which shows typically the taking-out apparatus of 1st Embodiment. It is a perspective view which shows typically the mechanical clamp part with which the said taking-out apparatus is provided. It is sectional drawing which shows typically the taking-out apparatus of 2nd Embodiment. It is sectional drawing which shows typically the state in which the said taking-out apparatus hold | maintains the inner peripheral part of a disc board | substrate by a mechanical clamp part. It is a top view which shows the said mechanical clamp part and a sprue chuck. It is a perspective view which expands and shows a clamp member. It is sectional drawing which shows typically an example of the conventional disc substrate taking-out apparatus. It is a top view which shows typically the state by which the conveyance arm of the conventional taking-out apparatus is rotated with respect to the metal mold | die for shaping | molding.

Explanation of symbols

DESCRIPTION OF SYMBOLS 3 Disc substrate 4 Sprue 5 Molding die 6 Injection device 7 Taking out device 8 Nozzle 11 Fixed side die 12 Movable side die 13 Stamper 15, 16 Platen 17 Cut punch 18 Ejector pin 19 Ejector 21 Sprue chuck 22 Vacuum suction pad 23 Mechanical clamp unit 24 Drive unit 26 Heater 27 Clamp member 31 Transfer arm 31a First hand 31b Second hand 32 Motor

Claims (10)

A molding process in which a disk substrate is injection-molded with a molding die;
A mold release step of releasing the disk substrate from the mold body;
A method of manufacturing a disk substrate, comprising: a step of holding the disk substrate by a holding means whose temperature is controlled and taking out the disk substrate from the molding die.   The method of manufacturing a disk substrate according to claim 1, wherein in the removing step, the disk substrate is mechanically held by the holding unit.   The disk substrate manufacturing method according to claim 2, wherein in the taking out step, at least one of an outer peripheral portion and a center hole of the disk substrate is held by the holding means.   4. The method of manufacturing a disk substrate according to claim 1, wherein, in the removing step, the holding unit is controlled to a constant temperature in accordance with a temperature of the disk substrate. 5.   5. The method of manufacturing a disk substrate according to claim 1, wherein the holding step further uses another holding means for holding the disk substrate with a negative pressure. 6. Holding means for holding a disk substrate molded with a molding die;
Drive means for moving the holding means relative to the molding die;
A disk substrate take-out device comprising temperature control means for controlling the temperature of the holding means.   The disk substrate take-out device according to claim 6, wherein the holding unit mechanically holds the disk substrate.   The disk substrate take-out device according to claim 7, wherein the holding means holds at least one of an outer peripheral portion and a center hole of the disk substrate.   9. The disk substrate take-out device according to claim 6, wherein the holding means is controlled to a constant temperature according to the temperature of the disk substrate.   The disk substrate take-out device according to any one of claims 6 to 9, further comprising other holding means for holding the disk substrate by a negative pressure.

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