JP2001110098A - Apparatus for manufacturing optical disk - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus for manufacturing an optical disk which is capable of bonding two disk substrates varying in the coefficient of thermal expansion each other while preventing the occurrence of a warpage. SOLUTION: The surface temperature of a pallet 14 on which an optical disk element assembly 7 formed by superposing the two disk substrates 8 and 9 on each other via a photosetting adhesive 10 interposed therebetween is to be mounted, is measured by a temperature measuring instrument 13. The surface temperature of the pallet 14 is controlled by a temperature control means in accordance with the temperature detected by the temperature measuring instrument 13 so as to attain a prescribed value. The pallet 14, which is subjected to the temperature measurement by the temperature measuring instrument 13 and at which the optical disk element assembly 7 is mounted is transferred to a photoirradiation position where the optical disk element assembly 7 is irradiated with UV rays or visible rays from a lamp 11 and both disk substrates 8 and 9 are bonded with a photosetting adhesive 10 cured by photoirradiation, to manufacture the optical disk.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to an optical disk manufacturing apparatus used in a bonding process of two disk substrates in a manufacturing process of an optical disk body such as a (digital video disk).

[0002]

2. Description of the Related Art Optical disks such as CDs (compact disks) and DVDs are rotating recording disks (disk media).
Is a large-capacity memory that records and reproduces information by irradiating the laser with lasers. It has high recording density and has a large feature of portability of large amounts of information. It is attracting attention as being able to cope with a dramatic increase in the amount of information.

At present, in the field of optical disks, DVDs with very little noise are about to occupy a large weight in the market, and this DVD is generally manufactured through the following manufacturing process. That is, for example, a resist coated on a thick glass disk is exposed to a short-wavelength laser such as an argon ion laser and the like, and positioning marks are formed by development, and then an electrode is formed, followed by nickel plating and stamper (gold). Mold), and using this stamper as a master, plastic molding is performed by injection molding or the like, and a disk substrate is completed.
The disk substrate is coated with a recording layer, and the two disk substrates are bonded together such that the recording layer is sealed inside, thereby completing a disk medium having uneven positioning marks and groups.

In recent years, in the field of DVDs, the technique of bonding the above-mentioned two disk substrates has become increasingly important. As a bonding means, there is a photocurable material which is cured by irradiation with ultraviolet light or visible light. A method using an adhesive is mainly employed. Next, a description will be given of a step of bonding two disk substrates, which is conventionally employed.

FIG. 5 is a schematic plan view showing a conventional manufacturing apparatus for bonding two disk substrates 8, 9, and FIG.
(A) is a side view thereof, and (b) is an enlarged view of a portion A in (a). In these figures, two support arms 3 are fixed to a turntable 2 which is rotationally driven by a motor 1 as a drive source in such a manner as to project outward in opposite directions in the same radial direction. Pallets 4 are fixed to the distal ends of the arms 3, respectively. On each pallet 4, an optical disk element 7 is attached. As shown in FIG. 6B, the optical disk body 7 is in a state where the lower disk substrate 8 and the upper disk substrate 9 are overlapped with a light-curable adhesive 10 interposed therebetween in a separate step. And a center support hole (not shown)
The pallet 4 is mounted on the pallet 4 in a fixed state in which a projection (not shown) of the pallet 4 is fitted therein, and is rotated by driving the motor 1.

[0006] Each optical disk element 7 shown by a dashed line in FIG.
A lamp 11 for irradiating ultraviolet light or visible light is provided at a position above the rotation locus of the lamp. Accordingly, the optical disk element 7 is rotated by the drive of the motor 1, and emits ultraviolet light or visible light emitted from the lamp 11 and reflected by the reflecting mirror 12 when passing through the position immediately below the lamp 11. Thus, the upper and lower disk substrates 9 and
8 is adhered and fixed to form an optical disk.

[0007]

On the other hand, for an optical disk on which information is recorded at a high density, such as a DVD, it is particularly required that the warpage is extremely small as a condition for improving the quality. However, in the conventional manufacturing apparatus for bonding the two disk substrates 8 and 9, in particular, the two disk substrates 8 and 9 made of materials having different thermal expansion coefficients from each other are used.
9 is not provided with means for absorbing the difference in the coefficient of thermal expansion,
Warpage tends to occur due to the difference in the amount of elongation due to the temperature change in No. 9 and the quality of the optical disc cannot be improved.

In view of the above, the present invention has been made in view of the above-mentioned conventional problems, and enables two disk substrates having different coefficients of thermal expansion to be bonded to each other while reliably preventing warpage. It is an object of the present invention to provide an optical disk manufacturing apparatus.

[0009]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an optical disk element comprising two disk substrates stacked with a photo-curable adhesive therebetween, to apply ultraviolet or visible light. Irradiation, in the optical disc manufacturing apparatus for manufacturing an optical disc by bonding the two disk substrates with the photocurable adhesive that is cured by the light irradiation,
A pallet in which the optical disk body is mounted in such a manner as to contact one of the disk substrates, a temperature measuring device for measuring the surface temperature of the pallet, and a surface temperature of the pallet based on a temperature detected by the temperature measuring device. A temperature adjusting means for controlling the optical element to a predetermined value, a lamp for irradiating the optical disk element with light, and a pallet having a surface temperature controlled by the temperature adjusting means and having the optical disk element mounted thereon, and And a drive source for transferring a body to a position where the body is irradiated with light by the lamp.

This optical disk manufacturing apparatus includes a temperature measuring device for measuring the surface temperature of the pallet, and a temperature adjusting means for controlling the surface temperature of the pallet to a predetermined value based on the temperature detected by the temperature measuring device. Therefore, if the thermal expansion coefficients of the pair of disk substrates in the optical disk element body are different from each other, the surface temperature of the pallet is adjusted to a predetermined value based on the difference between the thermal expansion coefficients of the two disk substrates prior to light irradiation by the lamp. If the temperature of the disk substrate that contacts the pallet is adjusted, the difference in the coefficient of thermal expansion between the two disk substrates is absorbed by the temperature difference between the two disk substrates, and the temperature of the two disk substrates when they are bonded together with an adhesive. Elongation amount can be equalized. As a result, an optical disk produced by bonding a pair of disk substrates with an adhesive that is cured by light irradiation always has high quality without warpage.

In the above invention, the temperature adjusting means adjusts a flow path of the temperature adjusting medium provided inside the pallet, a supply path for supplying the temperature adjusting medium to the flow path, and a supply flow rate of the temperature adjusting medium. And a supply flow rate adjusting means.

Thus, the temperature control medium is directly supplied to the flow passage provided inside the pallet, and the surface temperature of the pallet is adjusted by the supply amount of the temperature control medium. , And a high-quality optical disk without warpage can be obtained at a high yield.

In the above arrangement, the supply flow rate is adjusted so that the surface temperature of the pallet becomes the predetermined temperature based on the predetermined temperature set based on the information on the two disk substrates of the optical disk to be manufactured and the temperature detected by the temperature measuring device. It is preferable that a controller for electrically feedback-controlling the means is provided.

Thus, the surface temperature of the pallet can be automatically and accurately adjusted, and even when the type of a pair of disk substrates in the optical disk body mounted on the pallet changes, the disk body can be adjusted. By inputting or specifying information on the pair of disk substrates, the setting of the surface temperature of the pallet can be automatically switched to respond.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic plan view showing an optical disk manufacturing apparatus for bonding two disk substrates 8 and 9 according to an embodiment of the present invention, FIG. 2 (a) is a side view thereof, and FIG. Is B in (a)
It is an enlarged view of a part. In these drawings, the same or equivalent components as those in FIGS. 5 and 6 are denoted by the same reference numerals, and the description thereof will be omitted. The following describes different configurations.

Each optical disk element 7 indicated by a chain line in FIG.
A radiation thermometer 13 is installed at a position above the turning trajectory and on the near side in the turning direction with respect to the lamp 11. The radiation thermometer 13 receives radiant energy from the temperature measuring object at a position separated from the temperature measuring object and measures the temperature in a non-contact manner. In this embodiment, the total radiation energy from the object to be measured is collected on a heat receiving plate, and the temperature rise is converted into a thermoelectromotive force or a resistance value to measure the temperature, or silicon, lead sulfide, cadmium sulfide, or the like. Any of those using a semiconductor such as these and measuring the temperature utilizing these photoelectric characteristics can be used. This radiation thermometer 13
Is capable of accurately measuring a relatively wide range of temperature. In this embodiment, the surface temperature of the rotating pallet 14 is measured by the radiation thermometer 13 in a non-contact manner. The temperature may be measured with a contact thermometer.

FIG. 3 is an enlarged plan view of the place where the pallet 14 is installed, and FIG. 4 is a partially cutaway side view of the place where the pallet 14 is installed. As shown in FIG. 3, flow grooves 17 for the temperature control medium are formed on the lower surfaces of both pallets 14, and each of the flow grooves 17 has a continuous shape while making a U-turn every round. ing. This distribution groove 17
Is covered by a lid 18 fixed to the lower surface of the pallet 14 to form a flow path for the temperature control medium. The temperature control medium supplied through the supply tube 20 circulates in the flow path, and the circulated temperature control medium is discharged from the flow path. In this embodiment, a cooling medium made of air is used as the temperature adjusting medium, and the cooling medium that has finished circulating through the flow passage in the pallet 14 is discharged to the atmosphere. In addition, as a cooling medium, in addition to air, a liquid such as gas or water may be used to circulate the cooling medium that has been circulated through the flow passage in the pallet 14 to a supply source.

A controller 21 shown in FIG. 2 controls a flow rate of a solenoid valve based on a set temperature calculated by an operation based on information input from an input unit 22 and a detected temperature on the surface of a pallet 14 input from a radiation thermometer 13. The solenoid of the valve 19 is electrically controlled to regulate the supply flow rate of the cooling medium.

Next, the operation of the optical disk manufacturing apparatus will be described. The motor 1 rotates and the pallet 1
4 is transferred to a position immediately below the radiation thermometer 13, the radiation thermometer 13 measures the surface temperature of the pallet 14 before attaching the optical disk element 7 to the pallet 14, and the detected temperature data is obtained. Output to the controller 21. On the other hand, information such as the coefficient of thermal expansion of both disk substrates 8 and 9 to be bonded is input from the input unit 22 to the controller 21 by operating the input unit 22 by the operator. The controller 21 calculates the set temperature of the pallet 14 by calculation based on the difference between the coefficients of thermal expansion of the pair of disk substrates 8 and 9 input from the input unit 22, and calculates the calculated set temperature and the temperature from the radiation thermometer 13. The difference from the detected temperature is calculated, and the solenoid of the flow control valve 19 is electrically controlled so that the difference becomes zero, thereby adjusting the supply flow rate of the cooling medium to the pallet 14. That is, the controller 21 performs feedback control of the solenoid of the flow control valve 19 based on the temperature detected by the radiation thermometer 13 so that the surface temperature of the pallet 14 becomes the calculated set temperature.

Therefore, the pallet 14 is cooled by the cooling medium having the flow rate adjusted by the flow rate control valve 19 being supplied through the supply tube 20 and circulating through the flow path including the flow groove 17 and the lid 18. Is controlled to be the calculated set temperature.
Pallet 14 whose surface temperature has been adjusted to the set temperature
The optical disk body 7 in which the two disk substrates 8 and 9 are overlapped with the photocurable adhesive 10 interposed therebetween is mounted in such a manner that the disk substrate 8 having the larger coefficient of thermal expansion is positioned below. Can be As a result, the lower disk substrate 8 in contact with the surface of the pallet 14 cooled and held at the predetermined temperature is transferred to the pallet 14 and cooled to the predetermined temperature.

Subsequently, the optical disk element 7 mounted on the pallet 14 is rotated when the turntable 2 is rotated in the direction indicated by the arrow in FIG. The two disk substrates 8 and 9 are adhered to each other with a photocurable adhesive 10 which is irradiated with ultraviolet light or visible light emitted from the lamp 11 and reflected by the reflecting mirror 12 to be cured to form an optical disk. At this time, since the lower disk substrate 8 is cooled to a lower temperature than the upper disk substrate 9 by an amount corresponding to the larger thermal expansion coefficient, the difference in the thermal expansion coefficient between the two disk substrates 8 and 9 is reduced. Absorbed by the temperature difference between 8, 9 and the elongation by the temperature of both disk substrates 8 and 9 becomes equal, and the optical disk formed by bonding both disk substrates 8 and 9 with adhesive 10 has high quality without warpage. It becomes something.

Moreover, in the manufacturing apparatus for bonding the two disk substrates 8 and 9 described above, the controller 21 calculates the set temperature calculated by the temperature of the pallet 14 detected by the radiation thermometer 13 and the input information from the input unit 22. When the optical disk element 7 to be manufactured changes, information such as the coefficient of thermal expansion of both disk substrates 8 and 9 in the optical disk element 7 is input. This can be handled simply by inputting or inputting the input information from the section, and the surface temperature of the pallet 14 can be automatically and accurately managed corresponding to the optical disk element 7.

In the above-described embodiment, a case has been described in which the pallet 14 and, consequently, the disk substrate 8 below the optical disk element body 7 are cooled using a cooling medium to control the temperature to a predetermined temperature. By controlling the surface temperature of the pallet 14 to a predetermined temperature using a heating medium,
Even when the optical disk element 7 is mounted on the pallet 14 with the disk substrate 8 or 9 having the smaller coefficient of thermal expansion positioned below, the same effect as described above can be obtained.

[0024]

As described above, according to the optical disk manufacturing apparatus of the present invention, the temperature measuring device for measuring the surface temperature of the pallet, and the surface temperature of the pallet becomes a predetermined value based on the temperature detected by the temperature measuring device. In the case where the coefficient of thermal expansion of the pair of disk substrates of the optical disk body is different from each other, the surface temperature of the pallet is set to a predetermined value so that both disk The difference between the coefficients of thermal expansion of the substrates is absorbed by the temperature difference between the two disk substrates, and the amount of elongation due to the temperature of the two disk substrates can be equalized. Therefore, a pair of disk substrates is bonded with an adhesive that is cured by light irradiation. The resulting optical disc always has high quality without warpage.

[Brief description of the drawings]

FIG. 1 is a schematic plan view showing an optical disk manufacturing apparatus according to an embodiment of the present invention.

FIG. 2 (a) is a side view of the manufacturing apparatus, and FIG. 2 (b) is an enlarged view of a portion B in FIG. 2 (a).

FIG. 3 is an enlarged plan view of a place where pallets are installed in the same device.

FIG. 4 is a partially cutaway side view of the same pallet installation location.

FIG. 5 is a schematic plan view showing a conventional optical disk manufacturing apparatus.

FIG. 6 (a) is a side view of the same manufacturing apparatus, and FIG. 6 (b) is an enlarged view of part A of FIG.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 motor (drive source) 7 optical disk element body 8, 9 disk substrate 10 light-curable adhesive 11 lamp 13 radiation thermometer (temperature measuring device) 14 pallet 17 flow groove (flow passage) 19 flow control valve (supply flow control means) ) 20 Supply tube (supply route) 21 Controller

Claims (3)

[Claims] 1. The photocurable adhesive, which is irradiated with ultraviolet light or visible light to an optical disc element formed by laminating two disk substrates with a photocurable adhesive therebetween, and is cured by the light irradiation. An optical disk manufacturing apparatus for manufacturing an optical disk by bonding both disk substrates together, comprising: a pallet in which the optical disk body is mounted so as to contact one of the disk substrates; and a measuring device for measuring a surface temperature of the pallet. A temperature controller, a temperature controller for controlling the surface temperature of the pallet to be a predetermined value based on a temperature detected by the temperature detector, a lamp for irradiating the optical disk element with light, and a surface controller for controlling the surface temperature by the temperature controller. The pallet, which is controlled and has the optical disk element mounted thereon, is irradiated with light from the optical disk element by the lamp. Manufacturing device of an optical disk, characterized by being constituted by a drive source for transporting the that position. 2. The temperature control means includes a flow path for the temperature control medium provided inside the pallet, a supply path for supplying the temperature control medium to the flow path, and a supply flow rate for controlling the supply flow rate of the temperature control medium. The optical disk manufacturing apparatus according to claim 1, further comprising an adjusting unit. 3. A supply flow rate such that the surface temperature of the pallet becomes the predetermined temperature based on a predetermined temperature calculated and set based on information on two disk substrates of an optical disk to be manufactured and a temperature detected by a temperature measuring device. 3. The optical disk manufacturing apparatus according to claim 2, further comprising a controller for electrically feedback-controlling the adjusting unit.