JP2006134545A - Method for manufacturing optical recording medium, and its device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing optical recording medium, which is suitable to a DVD-9 and a next-generation multilayered disk, and which allows adhesive layer with a high light transmittance to be bonded to a substrate without shortage and protrusion at a substrate end using an UV adhesive, even if a discrete substrate has a warpage or variation in thickness, and its device. <P>SOLUTION: According to the method for manufacturing an optical recording medium, a predetermined quantity of an UV curable adhesive is applied on a lower substrate in a ring shape and the adhesive layer is formed, and positioning of an upper substrate is controlled up to such a position that a distance between the substrates becomes equal to a required thickness of the adhesive layer while maintaining the correction and holding of the upper substrate and the lower substrate. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical recording medium manufacturing method and apparatus, and more particularly to a bonding technique such as a DVD medium for bonding a 0.6 mm thick substrate, a next generation medium for bonding a 0.1 mm substrate, and the like.

  In recent years, the bonding of DVD media consisting of two discs with a thickness of 0.6 mm has a low material unit price, a short curing time, good heat resistance after curing, and good productivity. desired. For this reason, ultraviolet curable adhesives (hereinafter referred to as UV adhesives) have been widely used instead of thermosetting and two-component mixed adhesives.

  In addition, in the case of a double-sided type called DVD-9, in the case of a next generation optical disk or the like for the next generation media, a 0.1 mm cover substrate method proposed for next-generation media, and an information recording layer formed in multiple layers to increase the capacity. Since the substrate or the adhesive layer between the upper recording layer and the lower recording layer requires a uniform and high light transmittance, a screen printing method in which a large amount of microbubbles are mixed can be used as a method for forming the adhesive layer. In addition, the construction method using an adhesive sheet is not suitable for practical use because the material cost of the adhesive sheet is high. Therefore, a spin coating method is mainly used in which an adhesive layer is formed by dropping UV adhesive more than necessary and then rotating at high speed to shake off the excess and irradiating and curing with UV light. ing.

Here, a conventional example using this spin coating method will be described below with reference to FIGS.
FIG. 17 is a schematic view showing a state of UV adhesive application by a spin coating method. In the figure, a lower substrate 101 which is one side of substrates before bonding is rotated at a constant speed by a speed control motor 102, and a liquid UV adhesive 104 is discharged from an adhesive application nozzle 103. The UV adhesive 104 has a concentric annular shape. At this time, the discharge of the UV adhesive 104 is performed between the adhesive application nozzle 103 and the adhesive tank 105 by pressing the internal pressure of the adhesive tank 105 containing the liquid UV adhesive 104 to an appropriate pressure by the regulator 106. On / off control of discharge is performed by the air valve 107. In this bonding method, the discharge amount largely fluctuates due to environmental temperature fluctuations. Further, when the air valve 107 is closed, a pulsation in which a slightly larger amount of the UV adhesive 104 is discharged occurs.

  Next, the conventional bonding process will be described with reference to FIG. 18, which shows the process. As shown in FIG. 18A, the lower substrate 111 to which the UV adhesive 112 is applied in an annular shape is a lower substrate. It is sucked and held by a suction hole (not shown) provided in the holder 113. At this time, the lower substrate 111 is positioned at the center with high accuracy by the center boss 114 provided on the lower substrate holder 113. Next, the upper substrate 116 is transferred directly above the lower substrate 111 by the substrate transport jig 115. At this time, the upper substrate 116 and the substrate transport jig 115 are held by a suction pad 117 made of a soft material such as silicon so as not to damage the substrate. Then, as shown in FIG. 18B, the substrate transport jig 115 is gradually lowered, and when the UV adhesive 112 applied in an annular shape comes into contact, the suction holding is released, and the substrate transport jig 115 is released. Is raised and retracted, the lower substrate holder 113 is rotated at a high speed, whereby the excess adhesive 118 is shaken off, and a uniform and less uneven adhesive layer 119 is formed between the upper substrate 116 and the lower substrate 111. . At this time, as shown in FIG. 18 (c), the protruding portion 120 of the trace of the excess adhesive 118 remaining on the outer peripheral end portions of the upper substrate 116 and the lower substrate 111 which are bonded together remains substantially over the entire periphery. On the inner peripheral side, there are recesses called stamper pressing grooves 121 each having a depth of about 0.2 mm in the upper substrate 116 and the lower substrate 111, and the adhesive 112 is generally extended to the stamper pressing grooves 121. It is. Since the stamper pressing groove 121 serves as a buffer, the spreading of the adhesive 112 is temporarily stopped and the center boss 114 is prevented from being soiled. However, when the environmental temperature fluctuates, the frequency of occurrence of defects increases. For example, when the environmental temperature is lower than usual, the adhesive viscosity becomes high, and the discharge amount of the adhesive becomes smaller than the set amount, and the spread of the adhesive toward the inner peripheral side is reduced. As shown in FIG. 19 (a) which is a plan perspective view and FIG. 19 (b) which is a partially enlarged cross-sectional view, when it does not reach the stamper pressing groove 121 which is a target position for extension, it will appear as a lack of extension 122. It becomes a defective product. On the other hand, when the environmental temperature becomes higher, the discharge amount increases. As a result, if it extends too much beyond the target position, it becomes a poor appearance product as an excessively extended 123. In addition, if the discharged adhesive has pulsation and there are many local portions, the spreading of the portion proceeds faster than others, and the slowed portion is surrounded to become a bubble 124, which is also a defective appearance product.

  FIG. 20 is a process cross-sectional view showing a bonding process for a substrate having some warpage. In the figure, the same reference numerals as those in FIG. 18 denote the same components. Here, there is some warpage in the substrate itself, and the amount of warpage varies depending on the substrate molding conditions and storage environment, and is difficult to make constant. As shown in FIG. 20A, the outer peripheral side of the upper substrate 116 is warped upward. In this case, even if the lower substrate 111 side is corrected to a flat surface, the upper substrate 116 side is rotated at a high speed. However, the force to return to the original shape works and the adhesive layer on the outer peripheral side becomes thick. Along with this, defects such as insufficient spreading and excessive spreading are likely to occur at the inner and outer peripheral edges.

  As described above, the spin coating method has an advantage that a uniform adhesive layer can be formed in a short time. However, since the centrifugal force is used, the resin always protrudes from the outer peripheral edge of the substrate, and it is scattered by shaking. There is a disadvantage that the equipment cost and labor cost required for collecting and maintaining the surplus adhesive are high. In addition, since the portion where the resin protrudes is a portion that is directly touched by the user, if it is not uniform, it causes a problem in appearance and touch. Furthermore, in order to cure the resin in the protruding portion, it is necessary to irradiate UV light several times as much as necessary, so that the warp quality of the disc, the production tact time, and the life of the UV lamp But it becomes a problem.

Therefore, some proposals have been made conventionally. As one of them, Patent Document 1 proposes an optical disc manufacturing method and manufacturing apparatus in which an adhesive is not protruded from an optical disk in the case of bonding, and the amount of adhesive used is minimized. Yes. In the optical disk manufacturing method of Patent Document 1, when the signal recording substrate and the protective substrate are bonded, a UV curable adhesive is applied concentrically near the center hole of the signal recording substrate, the protective substrates are overlapped, After the predetermined time has been rotated, the rotation is stopped, and after the second predetermined time has elapsed, ultraviolet irradiation is performed. Further, in Patent Document 2, in order to prevent the adhesive from protruding from the outer periphery and the inner periphery of the optical disk, the protective film layer of each disk substrate serving as an adhesive surface is provided from the outer peripheral edge and the inner peripheral edge of the disk substrate. By forming in the region excluding the width region, the adhesive that protrudes from the protective film layer during bonding can be applied to the outer peripheral edge and the thickness of the two protective film layers and the region where the protective film layer is not formed. This is a method of staying in a ring-shaped space formed at the inner peripheral end. Further, in Patent Document 3, in order to prevent the adhesive layer from protruding or protruding when the pair of substrates are bonded together, and to reduce the time required for the manufacturing process, the pair of substrates are bonded together to at least both of the substrates. When manufacturing an optical recording medium provided with an information recording part on one side, an adhesive layer on the carrier tape is used using a releasable carrier tape in which an adhesive layer having a shape corresponding to the disk shape of the substrate is arranged on the tape surface. Is transferred onto one substrate, and then the substrate and the other substrate are bonded together via the transferred adhesive layer. Also, in Patent Document 4, two disc substrates are used in an optical disc in which two disc substrates formed with a recording surface and a reflective layer covering the recording surface are bonded together via an adhesive layer. This is a method of forming a printing layer for preventing the adhesive from protruding into the groove on the outer periphery of the groove of the stamper holder mark.
JP-A-5-20714 JP-A-9-91760 JP-A-9-91774 Japanese Patent Laid-Open No. 10-11800

  However, although the above-mentioned Patent Document 1 was actually tried, when the substrate sandwiched with the adhesive was rotated, it did not spread and spread concentrically and became non-uniform like an amoeba, and up to the outer edge. The time for completing the concentric circular expansion is approximately 5 minutes per sheet, which is not practical, and even if the substrate has warpage, it did not extend to the outer peripheral edge even after several tens of minutes. According to Patent Document 2, screen printing is used to form a protective layer in a region excluding a region having a predetermined width, and therefore there are microscopically scattered portions having no protective layer, and the entire surface of the disk is scattered. Cannot be used for DVD-9 or multilayer discs that require uniform light transmittance. Further, although the above-mentioned Patent Document 3 can surely prevent the protrusion, it requires a great deal of cost to produce a releasable carrier tape, and the cost per bonded disc is UV bonding. It is not practical because it is 30 times more than the method using an agent. In addition, the above-mentioned Patent Document 4 requires a wall to be printed by printing on both the upper and lower substrates in advance, which greatly increases the cost, and the adhesive easily gets over the wall when the substrate is crimped, preventing the protrusion. Can not.

  The present invention is for solving these problems, and is suitable for DVD-9 and next-generation multi-layer discs, and an adhesive layer having a high light transmittance is warped or has a variation in thickness. It is an object of the present invention to provide an optical recording medium manufacturing method and apparatus capable of being bonded to a substrate end without using a UV adhesive and without being insufficient or protruding.

  In order to solve the above-described problems, according to the method of manufacturing an optical recording medium of the present invention, a predetermined amount of an ultraviolet curable adhesive is circularly applied to the lower substrate to form an adhesive layer, and the upper substrate and the lower substrate are formed. It is characterized in that the positioning of the upper substrate is controlled to a position where the distance between the substrates becomes equal to the desired thickness of the adhesive layer while maintaining the correction of the substrates. Therefore, even if the substrate is warped, it is possible to form an adhesive layer that does not have a shortage or protrusion of the ultraviolet curable adhesive, eliminating the need for a surplus adhesive swing-off step, and greatly reducing manufacturing costs.

  Further, according to the method of manufacturing an optical recording medium of the present invention, the upper substrate and the lower substrate to be bonded are pressed with a predetermined thrust, and the stopped position is set as the origin position. Then, a predetermined amount of an ultraviolet curable adhesive is annularly applied to the lower substrate to form an adhesive layer, and the distance between the substrates is set to a desired thickness of the adhesive layer while keeping the upper substrate and the lower substrate straightened. The positioning of the upper substrate is controlled from the origin position to an equal position. Therefore, even if the thickness of the single substrate fluctuates, it is possible to form an adhesive layer that does not lack or protrude the ultraviolet curable adhesive, and can be adapted to DVD-9 and next-generation multilayer discs.

  Furthermore, according to the method for producing an optical recording medium of the present invention, the contact space state generated between the upper substrate holder that holds the upper substrate and the upper substrate is a vacuum suction state in which the upper substrate is sucked, an air release state, or Switching to a pressurized air supply state in which compressed air is supplied between the upper substrate holder and the upper substrate is performed, and the spread of the ultraviolet curable adhesive is controlled by changing the substrate gap. Therefore, even if the thickness of the upper and lower substrates fluctuates, it is possible to form an adhesive layer that does not have a shortage or protrusion of the ultraviolet curable adhesive. Since it becomes unnecessary, costs such as material costs, equipment costs, and maintenance costs can be greatly reduced.

  Further, by projecting ultraviolet rays in a spot manner in order to cure the ultraviolet curable adhesive in the limit area that determines the spread range of the ultraviolet curable adhesive, it is possible to prevent the protrusions on the inner and outer circumferences that define the spread range.

  Further, when the upper substrate and the lower substrate are bonded together and the UV curable adhesive is spread, a sensor that detects the protrusion of the UV curable adhesive from the outer peripheral edge of the bonded upper substrate and the lower substrate is used. By switching the state that occurs between the upper substrate holder and the upper substrate according to the detection result, it is possible to appropriately cope with the spread state fluctuation due to the viscosity change of the ultraviolet curable adhesive that changes due to the change in environmental temperature, It is possible to form an adhesive layer that does not lack or protrude from the curable adhesive.

  Further, according to the method for producing an optical recording medium of the present invention, when the ultraviolet curable adhesive is spread, the outer periphery of the bonded upper substrate and lower substrate is directed toward the boundary between the upper substrate and the lower substrate. Spray with compressed air. Therefore, even if the thickness of the upper and lower substrates fluctuates, it is possible to form an adhesive layer that does not protrude from the UV curable adhesive, eliminating the need for a swing-off process, greatly reducing costs such as equipment costs and maintenance costs. Can do.

  Furthermore, the timing and air volume of the compressed air blown toward the boundary between the upper substrate and the lower substrate according to the detection result by the sensor that detects the protrusion of the ultraviolet curable adhesive from the outer peripheral edge of the upper substrate and the lower substrate bonded together By controlling the above, it is possible to appropriately cope with the variation in the spread state due to the viscosity change of the ultraviolet curable adhesive that changes according to the change in the environmental temperature, and it is possible to form an adhesive layer that does not emit only the ultraviolet curable adhesive.

  Furthermore, an optical recording medium manufacturing apparatus according to another invention includes a lower substrate holder that holds and sucks and holds a substantially entire surface of the lower substrate in a flat surface, and is placed in parallel at the same center as the lower substrate holder. An upper substrate holder for correcting and holding almost the entire surface of the substrate to a flat surface, an elevating mechanism for elevating and lowering the upper substrate holder while being parallel to the center of the lower substrate holder, and a controller for controlling the position of the elevating mechanism It is equipped with. According to the apparatus for producing an optical recording medium of the present invention, a predetermined amount of an ultraviolet curable adhesive is circularly applied to a substrate to form an adhesive layer, and the upper substrate and the lower substrate are maintained in a straightened state. The controller controls the positioning of the upper substrate holder by the elevating mechanism until the distance between the substrates becomes equal to the desired thickness of the adhesive layer. Therefore, even if the substrate is warped, it is possible to form an adhesive layer that does not have a shortage or protrusion of the ultraviolet curable adhesive, eliminates the surplus adhesive swing-off step, and can provide a manufacturing apparatus that can greatly reduce manufacturing costs.

  Further, according to the optical recording medium manufacturing apparatus of another invention, the upper substrate and the lower substrate are pressed with a predetermined thrust while the upper substrate and the lower substrate to be bonded are held on the upper substrate holder and the lower substrate holder, respectively. The stopped position is the origin position. Then, a predetermined amount of an ultraviolet curable adhesive is annularly applied to the lower substrate to form an adhesive layer, and the distance between the substrates is set to a desired thickness of the adhesive layer while keeping the upper substrate and the lower substrate straightened. The controller controls the positioning of the upper substrate holder by the elevating mechanism from the origin position to the equal position. Therefore, even if the thickness of the single substrate fluctuates, it is possible to form an adhesive layer that does not lack or protrude the ultraviolet curable adhesive, and it is possible to provide a manufacturing apparatus that can also apply DVD-9 and next-generation multilayer discs.

Further, when the volume of the ultraviolet curable adhesive is V, the thickness of the ultraviolet curable adhesive layer is h, the inner radius is R1, and the outer radius is R2, the volume is V = πh (R2 ² −R1 ² ). By discharging the ultraviolet curable adhesive, the ultraviolet curable adhesive is applied only in an amount necessary for bonding, so that the swing-off process is not required, and the manufacturing cost can be reduced.

Further, when Rc is a radial position corresponding to the application position of the nozzle when discharging the ultraviolet curable adhesive, R1 is an inner radius of the adhesive layer to be formed, and R2 is an outer radius, Rc = √ ((( R1 ² + R2 ² ) / 2) By discharging the ultraviolet curable adhesive to the radial position, the total discharge amount of the ultraviolet curable adhesive does not change even if the environmental temperature or the adhesive viscosity changes. It is possible to always stably form an adhesive layer free from shortage and protrusion of a curable adhesive.

  Furthermore, by controlling the discharge of the ultraviolet curable adhesive with a plunger pump driven by an air cylinder, the discharge amount of the ultraviolet curable adhesive can be easily set.

  In addition, by driving the plunger pump with a pulse motor and a ball screw, the discharge speed is constant, pulsation is eliminated, and an adhesive layer that is more stable and does not have a shortage or protrusion of UV-curable adhesive can be formed. .

  Furthermore, a pulse motor for rotating the lower substrate holder and a rotation control unit for controlling the pulse motor to rotate at a constant speed are provided, and the lower motor holder is fixed by controlling the pulse motor by the rotation control unit. Rotate to speed. Therefore, the rotation speed is stabilized, the rotation unevenness is eliminated, and an adhesive layer free from shortage or protrusion of the ultraviolet curable adhesive can be formed more stably.

  In addition, the two-axis interpolation control of the pulse motor that controls the discharge of the UV curable adhesive and the pulse motor that controls the rotation of the lower substrate holder makes the UV curable adhesive evenly uneven even during high-speed driving. The adhesive layer can be formed without excess and deficiency.

  Furthermore, by providing an air passage on the outer diameter of the center boss at the center of the lower substrate holder, it is possible to form an adhesive layer that is even more stable and does not have a shortage or protrusion of the ultraviolet curable adhesive.

  In addition, by rotating the upper substrate or lower substrate at a low speed where centrifugal force does not work while spreading the UV curable adhesive, even if there is uneven thickness in the circumferential direction of the single substrate, UV curable adhesive It is possible to form an adhesive layer with no shortage or protrusion of the agent.

  Furthermore, an optical recording medium manufacturing apparatus according to another aspect of the present invention relates to a state of contact space generated between the upper substrate holder and the upper substrate in a vacuum suction state in which the upper substrate is sucked, an air release state, or the upper substrate holder and the upper substrate holder. Contact space state switching means for switching to either a compressed air supply state in which compressed air is supplied between the substrate and the substrate is provided, and the spread of the ultraviolet curable adhesive is controlled by changing the substrate gap. Therefore, even if the thickness of the upper and lower substrates fluctuates, it is possible to form an adhesive layer that does not have a shortage or protrusion of the ultraviolet curable adhesive. Since it becomes unnecessary, costs such as material costs, equipment costs, and maintenance costs can be greatly reduced.

  In addition, when the ultraviolet curable adhesive is spread, the optical recording medium manufacturing apparatus of another invention compresses from the outer periphery of the bonded upper and lower substrates toward the boundary between the upper and lower substrates. An air blowing mechanism that blows air is provided, and the spread of the ultraviolet curable adhesive at the outer peripheral end portion in the gap between the bonded upper substrate and lower substrate is controlled. Therefore, even if the thickness of the upper and lower substrates fluctuates, it is possible to form an adhesive layer that does not protrude from the UV curable adhesive, eliminating the need for a swing-off process, greatly reducing costs such as equipment costs and maintenance costs. Can do.

  Furthermore, by having a spot UV lamp that irradiates ultraviolet rays spotwise in order to cure the UV curable adhesive in the limit area that determines the spread range of the UV curable adhesive, Protrusion can be prevented.

  Also, when the upper substrate and the lower substrate are bonded together and the UV curable adhesive is spread, a sensor that detects the protrusion of the UV curable adhesive from the outer peripheral edge of the bonded upper substrate and the lower substrate is provided. Providing appropriate response to changes in the spread state due to changes in the viscosity of the UV-curable adhesive that changes with changes in the environmental temperature by controlling the air blowing timing and air volume by the air blowing mechanism according to the detection results of the sensor In addition, it is possible to form an adhesive layer that does not expose only the ultraviolet curable adhesive.

  In addition, the air spray mechanism can be configured by arranging a plurality of air nozzles in an annular shape, so that the flow rate of the sprayed air can be adjusted for each location, preventing the UV curable adhesive from protruding over the entire circumference. It is possible to make the thickness of the adhesive layer uniform.

  In addition, by rotating the air spray mechanism or spot UV lamp and the bonded upper and lower substrates relatively, it is possible to prevent the UV curable adhesive from protruding over the entire circumference, and the thickness of the adhesive layer. Can be made uniform.

  According to the present invention, since the adhesive layer is formed while the upper substrate and the lower substrate are both straightened and held by the parallel and flat substrate holder, there is no shortage or protrusion of the UV curable adhesive even if the substrate is warped. An adhesive layer can be formed. Moreover, since only the minimum amount of adhesive is applied for bonding, a swing-off process is not required, and manufacturing costs (material costs, equipment costs, maintenance costs) can be greatly reduced. Furthermore, even if the thickness of the single substrate fluctuates, it is possible to form an adhesive layer that does not lack or protrude the ultraviolet curable adhesive, and can be adapted to DVD-9 and next-generation multilayer discs.

  FIG. 1 is a process sectional view showing a manufacturing process by an optical recording medium manufacturing apparatus according to a first embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 17 denote the same components.

  First, as specifications of the optical recording medium to be manufactured, type: DVD + R (single-sided single layer recording (information substrate + transparent cover substrate bonding)), information substrate; inner diameter: φ15 mm, outer diameter: φ120 mm, thickness: 0.6 mm , Cover substrate; inner diameter: φ15 mm, outer diameter: φ120 mm, thickness: 0.6 mm, adhesive layer; inner diameter D1: φ22 mm, outer diameter D2: φ120 mm, thickness h: 50 μm. Further, the specifications of the UV adhesive used are: adhesive; Nippon Kayaku Co., Ltd. DVD003, viscosity: 450 cP.

  First, as in the conventional case, as shown in FIG. 17, the lower substrate 101 is sucked and held on a rotary table (not shown), and the rotation speed of the speed control motor 102 is set to 30 rpm and is rotated at a constant speed. Further, the tip of the adhesive application nozzle 103 is moved to a position about 0.6 mm above the lower substrate 101. Here, a uniform annular ring is formed by discharging 0.5 cc of the UV adhesive 104 over 2 seconds. Note that when the rotational speed of the lower substrate 101 is increased, the discharge time may be shortened in proportion thereto, and is not limited to the above. It is important that the UV adhesive 104 for just one round is discharged.

  Then, as shown in FIG. 1A, the upper substrate 11 is placed with the bonding surface down, and is positioned with high accuracy by the center boss 15 at the center of the lower substrate holder 12 and set without sucking and holding. . Next, the upper substrate holder 13 having high flatness is lowered by the elevating mechanism 14 and stopped at a point (Z = 0.6 mm) in contact with the upper substrate 11, and is above an adsorption hole described later on the upper substrate holder 13 side. The substrate 11 is held by suction. As shown in FIG. 1B, the upper substrate holder 13 is lifted and retracted by the elevating mechanism 14 to the position of Z = 50 mm while the upper substrate 11 is sucked and held. Next, as shown in FIG. 17, the lower substrate 101 to which the UV adhesive 104 is applied in an annular shape is positioned and set at the center with high accuracy by the center boss 15 at the center of the lower substrate holder 12 having high flatness. Hold. Then, as shown in FIG. 1C, the upper substrate holder 13 is lowered at a high speed (30 mm / s) to the position of Z = 3 mm while the upper substrate 11 is sucked and held, and from there, a low speed (0. 5 mm / s) and moved to the position of Z = 1.25 mm. At this final position, the total thickness of the upper and lower two substrates is 1.2 mm, so that a clearance of 50 μm is generated between the substrates. Until reaching the final position, the UV adhesive 104 is evenly spread inward and outward by the force sandwiched between the upper substrate 11 and the lower substrate 101. In addition to this, the UV adhesive 104 is simultaneously subjected to the force of wetting and spreading due to capillary action and the force of reaching the minimum volume, and the spreading becomes a perfect circle. Next, after the suction holding of the upper substrate holder 13 is released and moved to the position of Z = 3 mm at a low speed, it is lifted and retracted to a position of Z = 50 mm at a high speed. Then, the suction holding of the lower substrate holder 12 was released, the bonded substrate that had been spread out was taken out, transferred to a UV curing device (not shown), and then cured by UV irradiation. Alternatively, the UV lamp 17 is installed on the upper substrate holder 13, the upper substrate holder 13 is moved to a position of Z = 0.05 mm, and the UV lamp 17 is caused to emit light. Thereby, even if the substrate itself has a large warp, an adhesive layer having a uniform thickness could be formed. Note that the UV irradiation was pre-cured, that is, the irradiation area was a part, or the irradiation energy was low and the film was not completely cured. In this embodiment, the upper substrate holder 13 is made of Pyrex (registered trademark) glass so that UV light can pass through. A transparent resin such as acrylic may be used, but glass is superior in terms of UV light transmittance, rigidity, and flatness. Through a series of these operations, an adhesive layer extended to the target position without excess or deficiency could be formed. In addition, the bonded substrate, which had been spread out even before UV irradiation, showed a strong adhesive force, and even when a slight external force was applied, the upper and lower substrates were not misaligned. In order to adsorb the upper substrate 11, the upper substrate holder 13 is provided with suction holes with a diameter of φ1 mm equally divided into 8 locations at φ50 mm, 16 locations at φ80 mm, and 16 locations at φ110 mm. . Moreover, as described above, it has become possible to suppress the unevenness of the UV adhesive film thickness in the radial direction, but the uneven film thickness in the rotation direction depends on the surface accuracy of the substrate holder. Therefore, when the UV adhesive is spread, the suction gripping of the substrate is once released, the gap between the substrates is widened, the substrate holder is rotated 90 degrees during that time, and then returned to the predetermined gap three times. It has become possible to suppress film thickness unevenness in the rotation direction of the agent film thickness. Furthermore, since the amount of the UV adhesive was originally applied in the minimum amount necessary for spreading, the UV adhesive hardly moved even when the normal swing-off operation was performed. However, before irradiating with UV light, when the UV adhesive is rotated at a high speed such that it does not jump out from the edge of the substrate, for example, at 3000 rpm for 5 seconds, the film thickness distribution of the UV adhesive having a slightly thick inner circumference It was found that there is an effect of flattening. This makes it possible to form an adhesive layer having a uniform thickness in a shorter time.

  FIG. 2 is a process sectional view showing a manufacturing process by the optical recording medium manufacturing apparatus according to the second embodiment of the present invention. The specifications of the optical disk to be formed and the specifications of the adhesive used are the same as those in the first embodiment. In FIG. 2, the same reference numerals as those in FIG. 1 denote the same components.

  First, as shown in FIG. 2A, the upper substrate 11 and the lower substrate 101 are positioned and set with high accuracy by the center boss 15 at the center of the lower substrate holder 12. The lower substrate 101 is sucked and held on the lower substrate holder 12. Further, the upper substrate holder 13 is lowered by the elevating mechanism 14 and stops at a position just before the upper substrate holder 11 is in contact with the upper substrate 11. Then, the upper substrate 11 is sucked from the suction holes on the upper substrate holder 13 side. Switch to the torque control mode and further lower, stop at the point where the torque limit is reached, and set the origin (Z = 0 mm). Next, as shown in FIG. 2B, the upper substrate holder 13 is moved up and retracted by the elevating mechanism 14 to the position of Z = 80 mm while the upper substrate 11 is sucked and held. The retracted adhesive application nozzle 18 is moved, and the tip of the nozzle is set at a radius of 40 mm from the center. The pulse motor 16 for rotating the lower substrate is rotated at a constant speed of 30 rpm. Then, a uniform annular ring is formed by discharging 0.5 cc of the UV adhesive 104 over 2 seconds, and the adhesive application nozzle 18 is retracted. Then, as shown in FIG. 2 (c), the upper substrate holder 13 is lowered to a position of Z = 2 mm at a high speed (50 mm / s), and from there at a low speed (0.5 mm / s), Z = 0. Move to a position of 05 mm. At this final position, even if the total thickness of the upper and lower two substrates varies, a clearance of 50 μm is always generated between the substrates. Stop for 10 seconds in this state. During this time, the UV adhesive 104 is evenly spread inward and outward by the force sandwiched between the upper substrate 11 and the lower substrate 101. In addition to this, the UV adhesive 104 is simultaneously subjected to the force of wetting and spreading due to capillary action and the force of reaching the minimum volume, and the spreading becomes a perfect circle. Next, the suction holding of the upper substrate holder 13 is released, and the upper substrate holder 13 is raised and retracted to a position of Z = 80 mm at a high speed. Thereafter, the suction holding of the lower substrate holder 12 was released, and the bonded substrate that had been spread out was taken out, transferred to a UV curing device (not shown), and then cured by UV irradiation. Through a series of these operations, an adhesive layer extended to the target position without excess or deficiency could be formed. In addition, the bonded substrate in which spreading was completed even before UV irradiation showed a strong adhesive force, and the upper and lower substrates were not displaced even when a slight external force was applied. In the above-described operation, the pulse motor 16 for rotating the lower substrate is rotated at a constant speed at a low speed at which centrifugal force does not act on the UV adhesive 104 while it is stopped for 10 seconds. An extended adhesive layer could be formed without a shortage. The low-speed rotation speed at this time was 12 rpm. In this embodiment, the lower substrate 101 is rotated. However, it is important that the upper substrate 11 and the lower substrate 101 rotate relatively, and the lower substrate 101 is stopped and the upper substrate 11 is rotated. But there are similar effects.

Here, the minimum amount of UV adhesive required to produce one optical disk is calculated as follows. When the area of the UV adhesive layer to be formed is S, the height is h, the inner radius is R1, and the outer radius is R2, the amount of UV adhesive V = S · h = πh (R2 ² −R1 ² ) Become. As described above, the specifications of the UV adhesive layer are the inner diameter D1: φ22 mm, the outer diameter D2: φ120 mm, and the thickness h: 50 μm. Therefore, the inner radius R1 = 11 mm and the outer radius R2 = 60 mm. By substituting, the amount of UV adhesive V = 0.546 (cm ³ = cc) is calculated. When the discharge amount was set to this value, it became possible to always stably produce a bonded disc in which the UV adhesive was spread to the target position without excess or deficiency. However, environmental temperature and humidity, substrate wettability, substrate thickness, adhesive viscosity, etc. vary somewhat, and UV adhesives cure and shrink somewhat, so the above set amount is the center, and in fact ± 20% of it It is preferable to be in the range.

  Next, the optimum position for applying the UV adhesive from the UV adhesive application nozzle based on the minimum required amount of the UV adhesive calculated in this way will be described. As shown in FIG. When the inner radius of the adhesive layer is R1 and the outer radius is R2, the nozzle radius position Rc when discharging the UV adhesive is not the center of R1 and R2, but the position that bisects the required spread area is appropriate. It is guessed. If the radius position that bisects this area is Rc, the following equation is established.

^{S / 2 = π (Rc 2} -R1 2) = π (R2 2 -Rc 2)
By solving this,
Rc = √ ((R1 ² + R2 ² ) / 2).

  For example, if the inner radius R1 = 11 mm and the outer radius R2 = 60 mm are substituted into the above equation, the nozzle radius position Rc = 43.1 mm is calculated.

  When the radial position of the adhesive discharge nozzle was set to the calculated position, it became possible to always stably produce a bonded type disc in which the UV adhesive was spread to the target position without excess or deficiency. However, since there is some unevenness in the thickness of the substrate on the inner peripheral side and the outer peripheral side, it is preferable to set the above-mentioned set position as the center, and in practice within a range of ± 20%.

  FIG. 4 is a partial cross-sectional view showing the UV adhesive discharge control mechanism in the optical recording medium manufacturing apparatus of the present invention. In the optical recording medium manufacturing apparatus of the present invention, in order to spread the adhesive without excess or deficiency, there is no variation in the total discharge amount and no pulsation (the discharge amount per unit time is constant). Is an important condition.

  Therefore, in this embodiment, a plunger pump 41 shown in FIG. 4 is used in place of the “pressurized tank + air valve” method which is a conventional method of UV adhesive discharge control. The piping tube 42 connected to the IN side is put in an adhesive tank (not shown), and the plunger 43 in the plunger pump 41 is moved in the direction of arrow A in the drawing as shown in FIG. 44 is opened and the OUT side valve 45 is closed, and the UV adhesive is sucked up. After stopping at a predetermined position, as shown in FIG. 4 (b), the plunger 43 is moved in the direction of arrow B in the figure to close the IN side valve 44, the OUT side valve 45 is opened, and the adhesive is It is pushed out to the piping tube 46 connected to the OUT side and applied to the substrate from the adhesive application nozzle. At this time, the plunger 43 was moved by the air cylinder 47. Therefore, with this structure, the total amount of adhesive applied does not change even when the environmental temperature changes. As a result, an adhesive layer without excess or deficiency could always be formed stably.

  Further, the plunger 43 is moved by the air cylinder 47 as shown in FIG. 4, but the plunger 43 is moved by the pulse motor 52 and the ball screw 53 is moved as shown in FIG. 5 showing another discharge control mechanism of the UV adhesive. It can also be performed by the moving stage 51 used. Compared with the air cylinder drive system of FIG. 4, the pulsation component could be reduced. As a result, it was possible to apply the adhesive uniformly and uniformly, and an adhesive layer without excess or deficiency could always be formed stably. The drive source for rotating the ball screw 53 has the same effect as long as position control and speed control are possible, and is not limited to the pulse motor 52 but may be a servo motor or a direct drive motor.

  Next, when the rotation control of the lower substrate holder in the optical recording medium manufacturing apparatus of the present invention is changed from the speed control motor of the conventional example to the pulse motor and rotated at a constant speed, the rotation speed becomes stable. Rotation unevenness disappeared. As a result, it was possible to apply the adhesive uniformly and uniformly, and an adhesive layer without excess or deficiency could always be formed stably. The driving source for rotating the lower substrate holder has the same effect as long as position control and speed control are possible, and is not limited to a pulse motor but may be a servo motor or a direct drive motor.

  FIG. 6 is a block diagram showing the configuration of the control circuit in the optical recording medium manufacturing apparatus of the present invention. In the figure, two drivers, a motor driver 62 that drives a pulse motor 61 for driving a plunger and a motor driver 64 that drives a pulse motor 63 for rotating a lower substrate, are connected to a two-axis motor controller 65, and a two-axis motor. Two-axis interpolation control was performed by a host device 66 connected to the controller 65. In this control method, the discharge speed is changed in proportion to the rotation speed of the substrate. For example, in the section where the rotation speed of the substrate is accelerated, the plunger for discharging the adhesive is similarly accelerated. As a result, the amount of adhesive applied to the substrate per unit length is always equal, and even during high-speed driving using acceleration / deceleration control, the adhesive can be applied evenly and without any excess or deficiency. The adhesive layer could always be formed stably.

  FIG. 7 is a view showing the structure of the center boss of FIGS. 1 and 2. In the case of a substantially conical center boss as shown in FIG. 7 (a), the air sandwiched between the upper substrate and the lower substrate, the annularly applied adhesive and the center boss becomes a closed space, and natural spreading Rarely occurred to inhibit. In view of this, an improvement was made to cut the outer diameter of the center boss into a substantially triangular shape as shown in FIG. 7B so that the trapped air can be easily moved. As a result, the air sandwiched between the upper and lower substrates and the center boss easily moved, and as a result, an adhesive layer without excess or deficiency could always be formed stably.

  Here, how to deal with the case where there is variation in the thickness of the single substrates to be bonded together will be described. FIG. 8 is a cross-sectional view showing an example of a substrate having various thickness variations. A substrate 81 shown in FIG. 8A is an example of a substrate in which the right side of the figure is formed slightly thicker than the left side. The stampers number 125 shown in FIG. 19 is engraved on the substrates 82 and 83 shown in FIG. 8B, respectively, and the information recording surfaces of the two substrates are positioned so that the stamper numbers 125 overlap each other. Is set to face each other. In this state, a clearance 84 is generated between the upper substrate holder 13 in FIG. 1 and the surface of the substrate 83 corresponding to the upper substrate, and the substrate 83 corresponding to the upper substrate cannot often be adsorbed. Further, as shown in FIG. 8C, the clearance 84 on the left side of the figure is wide and the right side is narrow, and the UV adhesive cannot be spread evenly. Therefore, as shown in FIG. 8D, when the upper substrate 86 is rotated by 180 ° with respect to the lower substrate 85 and set, the thick portion and the thin portion overlap each other, so that the upper surface of the upper substrate 86 holds the lower substrate in FIG. The clearance generated between the upper substrate 11 and the lower substrate 101 by lowering the upper substrate holder 13 adsorbing the upper substrate 11 shown in FIG. The UV adhesive was able to spread evenly.

  Next, FIG. 9 is a schematic sectional view showing the structure of an optical recording medium manufacturing apparatus according to the third embodiment of the present invention. In the figure, the same reference numerals as those in FIG. 2 denote the same components. According to the optical recording medium manufacturing apparatus of the present embodiment shown in the same figure, the parallelism can be slid in a spherical shape below the lower substrate holder 12 and fixed at a desired position by vacuum suction. An adjustment mechanism 91 was added. With the parallelism adjusting mechanism 91 free, the upper substrate 11 is sucked from the suction hole on the upper substrate holder 13 side, switched to the torque control mode, further lowered, stopped when the torque limit is reached, and the origin When the operation of (Z = 0 mm) is performed, the free lower substrate 101 becomes parallel to the upper substrate 11. When the air is sucked so that a vacuum is generated in this state, the position of the lower substrate holder 12 is fixed, and the parallelism between the upper substrate 11 and the lower substrate 101 can be easily held.

  FIG. 10 is a process sectional view showing a manufacturing process by the optical recording medium manufacturing apparatus according to the fourth embodiment of the present invention. The specifications of the optical disk to be formed and the specifications of the adhesive used are the same as those in the second embodiment. In FIG. 10, the same reference numerals as those in FIG. 2 denote the same components.

  First, as shown in FIG. 10A, the upper substrate 11 and the lower substrate 101 are positioned and set with high accuracy by the center boss 15 at the center of the lower substrate holder 12. The lower substrate 101 is sucked and held on the lower substrate holder 12. Further, the upper substrate holder 13 is lowered by the elevating mechanism 14 and stops at a position just before the upper substrate holder 11 is in contact with the upper substrate 11. Then, the upper substrate 11 is sucked from the suction holes on the upper substrate holder 13 side. Switch to the torque control mode and further lower, stop at the point where the torque limit is reached, and set the origin (Z = 0 mm). Next, as shown in FIG. 10B, the upper substrate holder 13 is lifted to the position of Z = 80 mm by the elevating mechanism 14 and retracted while the upper substrate 11 is sucked and held. The saved adhesive application nozzle 18 is moved, and the tip of the nozzle is set at a radius of 38 mm from the center. The pulse motor 16 for rotating the lower substrate is rotated at a constant speed of 30 rpm. Then, a uniform circular ring is formed by discharging 0.55 cc of UV adhesive 104 over 2 seconds, and the adhesive application nozzle 18 is retracted. Then, as shown in FIG. 10 (c), the upper substrate holder 13 is lowered at a high speed (50 mm / s) to a position of Z = 2 mm, and from there, Z = 0 at a low speed (0.5 mm / s). Move to a position of 05 mm. At this final position, even if the total thickness of the upper and lower two substrates varies, a clearance of 50 μm is always generated between the substrates. Stop for 10 seconds in this state. During this time, the UV adhesive 104 is evenly spread inward and outward by the force sandwiched between the upper substrate 11 and the lower substrate 101. In addition to this, the UV adhesive 104 is simultaneously subjected to the force of wetting and spreading due to capillary action and the force of reaching the minimum volume, and the spreading becomes a perfect circle. After about 10 seconds, the UV adhesive 104 reaches the outer peripheral end. At that time, as shown in FIG. 10C, a sensor 92 for detecting the protrusion of the UV adhesive 104 from the end portion of the substrate is provided at the outer peripheral end portion of the substrate, and the substrate is detected when the protrusion of the UV adhesive 104 is detected. When the timing was controlled so as to return the gap between them to the original target value, it was possible to stably control the protrusion of the UV adhesive 104 even if the viscosity of the adhesive changed due to a change in room temperature. At this time, the protruding amount of the UV adhesive 104 was in a state of no visual and tactile problems. Further, since the upper substrate holder 13 is made of a transparent material such as acrylic or glass, it is possible to observe the spread of the UV adhesive from above. Further, as shown in FIG. 10C, a spot UV lamp 93 for spot-irradiating UV is provided on the inner peripheral portion of the substrate and the outer peripheral portion of the substrate, respectively, and the inner peripheral portion side extended by the spot UV lamp 93 and The UV adhesive 104 on the outer peripheral side is irradiated with UV in a spot manner and cured, so that the UV adhesive 104 does not extend beyond the target position on the inner peripheral side, and the UV adhesive 104 on the outer peripheral side becomes UV. The UV adhesive 104 can be spread without causing the adhesive 104 to protrude. Specifically, the UV adhesive 104 reaching the stamper pressing groove 94 provided on the surfaces of the inner peripheral side portions of the upper substrate 11 and the lower substrate 101 facing each other is spot-UVed from the spot UV lamp 93. Irradiation was performed to cure the UV adhesive 104 in the stamper pressing groove 94, and it was possible to suppress the occurrence of defects such as insufficient spreading or excessive spreading on the inner peripheral side. Next, the suction holding of the upper substrate holder 13 is released, and the upper substrate holder 13 is raised and retracted to a position of Z = 80 mm at a high speed. Thereafter, the suction holding of the lower substrate holder 12 was released, and the bonded substrate that had been spread out was taken out, transferred to a UV curing device (not shown), and then cured by UV irradiation.

  11 is a schematic cross-sectional view showing the configuration of the upper substrate holder of FIG. As shown to (a) of the figure, the upper board | substrate holder 13 has the contact glass 13-1 adhere | attached on the upper board | substrate 11, the glass holder 13-2 holding the contact glass 13-1, and the glass holder 13-. 2 and an arm 13-3 connected to a lifting mechanism (not shown). The contact glass 13-1 is provided with a number of suction holes 13-4 having a diameter of 1 mm, and the suction holes 13-4 communicate with a vacuum chamber 13-5 which is a space provided in the glass holder 13-2. ing. The vacuum chamber 13-5 is connected to an external suction pump (not shown) via a pipe joint 13-6. By the upper substrate holder 13 having such a configuration, a suction flow is generated by the suction pump through the pipe joint 13-6, the vacuum chamber 13-5, and the suction hole 13-4. The upper substrate 13 is sucked by the generated suction flow, and as shown in FIG. 11B, the upper substrate 11 is vacuum-sucked to the contact glass 13-1. Here, when it is connected to a vacuum pump with all the suction holes 54 closed, a force acts in the direction of decreasing the volume of the vacuum chamber 13-5, and the surface of the contact glass 13-1, which is a tempered glass having a thickness of 8 mm, is obtained. Deforms to dent. Conversely, when connected to a pneumatic pump, a force acts in the direction in which the volume of the vacuum chamber 13-5 increases, and the surface of the contact glass 13-1 is deformed so as to swell. The result of measuring the deformation at this time is shown in FIG. For example, when the pressure in the vacuum chamber is about −75 KPa, the surface of the contact glass is recessed by about 38 μm on the inner peripheral side (R = 22 mm) and 23 μm on the outer peripheral side. Similarly, for example, when the pressure in the vacuum chamber is about +50 KPa, the surface of the contact glass swelled by about 26 μm on the inner peripheral side (R = 22 mm) and 17 μm on the outer peripheral side. FIG. 13 schematically shows this state. (A) of FIG. 13 is an air release state, and the surface of the contact glass 13-1 is a plane. FIG. 13B shows a vacuum adsorption state, and the surface of the contact glass 13-1 is concave. Moreover, (c) of FIG. 13 is a pressurized air supply state, and the surface of the contact glass 13-1 is a convex surface. In addition, when the surface of the contact glass 13-1 is processed in advance so as to be a convex surface, the surface becomes flat when in a vacuum adsorption state, and an adhesive layer having a uniform film thickness can be easily formed and bonded. The thickness unevenness of the layer can be further reduced.

  Moreover, FIG. 14 is a figure which shows an example of the direction control valve which switches between an upper board | substrate and contact glass to a vacuum suction state, an air release state, or a pressurized air supply state. The directional control valve shown in the figure is a three-position double solenoid valve, which is held by two springs 94-1 and 94-2, and solenoids 95-1 and 95-2 are respectively provided at opposite ends. It is attached. When the energization of the two solenoids is not energized, the substrate holding side pipe and the exhaust pipe are communicated with each other and the atmosphere is opened. When the solenoid 95-2 is energized, the board holding side pipe and the vacuum pump pipe When the solenoid 95-1 is energized and switched to a vacuum suction state that communicates, the circuit is switched to a pressurized air supply state that communicates with the tube on the substrate holder side and the compressed air pump tube.

  As explained above, it is possible to spread without any shortage or overhang by a method such as adsorption that sets the gap between substrates to the original target value when the adhesive is spread, but the deflection of components such as arms is eliminated. Therefore, it takes several tens of seconds to reach the original gap between the substrates. Therefore, when the stop position of the vertical mechanism was made smaller than the original gap between the substrates, the UV adhesive spread to the outer peripheral edge, and the time required for it was shortened. However, it will protrude from the inner and outer peripheral edges in this state, so when the gap is gradually widened and returned to the original target value, it is possible to spread the UV adhesive in a short time without any shortage or protrusion. It became. Thus, when the adhesive is spread, the gap between the substrates is once narrower than the original target value and then returned to the original target value, so that the UV adhesive can be spread without shortage or protrusion in a short time. In addition, if the gap between the substrates is kept constant when the adhesive is spread, the spread gradually progresses, but when the gap between the substrates is changed in small increments with an amplitude of about ± 30 μm, the spread of the UV adhesive is somewhat It was quick. Furthermore, when the adhesive is spread, the suction grip of the substrate is once released, the gap between the substrates is widened, and the substrate holder is rotated by a predetermined angle during that time, and then returned to the predetermined gap, thereby improving the surface accuracy of the substrate holder. Even if there is a slight variation, since the operation of shifting the relative position of the substrate and the substrate holder is performed a plurality of times, film thickness unevenness in the rotation direction of the film thickness of the UV adhesive can be suppressed. Also, before irradiating with UV light, the UV adhesive is rotated at such a high speed that it does not jump out from the edge of the substrate, so that even if the inner peripheral side is slightly thicker in the adhesive film distribution Thus, an adhesive layer having a uniform film thickness can be formed in a short time.

  FIG. 15 is a process sectional view showing a manufacturing process by the optical recording medium manufacturing apparatus according to the fifth embodiment of the present invention. The specifications of the optical disk to be formed and the specifications of the adhesive used are the same as those in the second embodiment. In FIG. 15, the same reference numerals as those in FIG. 10 denote the same components.

  First, as shown in FIG. 15A, the upper substrate 11 and the lower substrate 101 are positioned and set with high accuracy by the center boss 15 at the center of the lower substrate holder 12. The lower substrate 101 is sucked and held on the lower substrate holder 12. Further, the upper substrate holder 13 is lowered by the elevating mechanism 14 and stops at a position just before the upper substrate holder 11 is in contact with the upper substrate 11. Then, the upper substrate 11 is sucked from the suction holes on the upper substrate holder 13 side. Switch to the torque control mode and further lower, stop at the point where the torque limit is reached, and set the origin (Z = 0 mm). Next, as shown in FIG. 15 (b), the upper substrate holder 13 is lifted to the position of Z = 80 mm by the lifting mechanism 14 while the upper substrate 11 is held by suction. The saved adhesive application nozzle 18 is moved, and the tip of the nozzle is set at a radius of 38 mm from the center. The pulse motor 16 for rotating the lower substrate is rotated at a constant speed of 30 rpm. Then, a uniform annular ring is formed by discharging 0.55 cc of UV adhesive 74 over 2 seconds, and the adhesive application nozzle 18 is retracted. Then, as shown in FIG. 15 (c), the upper substrate holder 13 is lowered to a position of Z = 2 mm at a high speed (50 mm / s), and from there, it is low speed (0.5 mm / s) and Z = 0. Move to a position of 05 mm. At this final position, even if the total thickness of the upper and lower two substrates varies, a clearance of 50 μm is always generated between the substrates. Further, the portion of the substrate itself where the UV adhesive 104 is applied in an annular shape is slightly bent due to its rigidity, and is in a depressed state. Therefore, it stops for 10 seconds in this state. During this time, the UV adhesive 104 is evenly spread inward and outward by the force sandwiched between the upper substrate 11 and the lower substrate 101. In addition to this, the UV adhesive 104 is simultaneously subjected to the force of wetting and spreading due to capillary action and the force of reaching the minimum volume, and the spreading becomes a perfect circle. After about 10 seconds, the UV adhesive 104 reaches the outer peripheral end. At that time, as shown in FIG. 15C, compressed air was blown from the outer peripheral side toward the boundary line of the upper and lower substrates by the air blowing mechanism 96. It has been found that the protrusion of the adhesive from the edge of the substrate changes depending on the pressure of the air sprayed, the shape of the tip of the nozzle, and the distance between the substrate and the nozzle. However, the protrusion occurred when the effect of spraying was small, but the protrusion could be blocked when the air volume was large. Moreover, when too much, air entered into the adhesive layer, resulting in an NG product. Therefore, when the shape of the nozzle for blowing air was a ring shape, the distance from the substrate edge was 2 mm, and the air supply pressure was 0.1 MPa, the air flow was just right. Even while the protruding adhesive is blocked by air blowing from this side, the release of the above-described deflection continues, and the clearance between the substrates becomes the designed value of 50 μm, and the adhesive layer film The thickness was almost uniform. Thereafter, air blowing from the side surface is stopped, and then the suction holding of the upper substrate holder 13 is released, and it is lifted and retracted to a position of Z = 80 mm at a high speed. Thereafter, the suction holding of the lower substrate holder 12 was released, and the bonded substrate that had been spread out was taken out, transferred to a UV curing device (not shown), and then cured by UV irradiation.

  When the pulse motor 16 for rotating the lower substrate is rotated at a constant speed at a low speed at which centrifugal force does not act on the UV adhesive 104 while it is stopped for about 10 seconds, the target position is further expanded to a sufficient extent. A stretched adhesive layer could be formed. The low-speed rotation speed at this time was 12 rpm. In the fifth embodiment, the lower substrate 101 is rotated. However, it is important that the upper substrate 11 and the lower substrate 101 rotate relatively, and the lower substrate 101 is stopped and the upper substrate 11 is rotated. Even if there is, there is a similar effect.

  FIG. 16 is a view showing another example of the air blowing mechanism of FIG. As can be seen from the plan view of FIG. 6A, the air blowing mechanism is a ring-shaped nozzle holder 97 in which 24 independent air nozzles 98 are arranged in an annular shape around the upper and lower substrates. is there. The air nozzle 98 used here had an inner diameter of 0.8 mm, was separated from the end face of the substrate by 2 mm, and the air supply pressure was 0.1 MPa. However, even when 24 nozzles are arranged in an annular shape, a minute protrusion may occur between the air nozzle and the air nozzle. Although improvement can be expected by further increasing the number of nozzles, when only the lower substrate 101 is rotated during air injection, the protrusions generated between the nozzles can be suppressed. Further, since the upper substrate holder 13 is made of a transparent material, for example, acrylic and glass, it is possible to observe the spread of the UV adhesive from above. Therefore, as shown in FIG. 16 (b), an image sensor 99 for spreading detection is added on the upper substrate holder 13, and air is blown when the spreading of the UV adhesive reaches the outer peripheral end. When the timing was controlled so as to spray, even if there was a change in the viscosity of the UV adhesive 104 due to a change in room temperature, it was possible to control the protrusion stably.

  In addition, this invention is not limited to the said embodiment, It cannot be overemphasized that various deformation | transformation and substitution are possible if it is description in a claim.

It is process sectional drawing which shows the manufacturing process by the manufacturing apparatus of the optical recording medium based on the 1st Example of this invention. It is process sectional drawing which shows the manufacturing process by the manufacturing apparatus of the optical recording medium based on the 2nd Example of this invention. It is a figure explaining the optimal position which apply | coats UV adhesive agent. It is a fragmentary sectional view which shows the discharge control mechanism of UV adhesive agent in the manufacturing apparatus of the optical recording medium of this invention. It is a fragmentary sectional view which shows another discharge control mechanism of UV adhesive agent in the manufacturing apparatus of the optical recording medium of this invention. It is a block diagram which shows the structure of the control circuit in the manufacturing apparatus of the optical recording medium of this invention. It is a figure which shows the structure of the center boss | hub of FIG.1 and FIG.2. It is sectional drawing which shows an example of the board | substrate which has dispersion | variation in various thickness. It is a schematic sectional drawing which shows the structure of the manufacturing apparatus of the optical recording medium based on the 3rd Example of this invention. It is process sectional drawing which shows the manufacturing process by the manufacturing apparatus of the optical recording medium based on the 4th Embodiment of this invention. It is a schematic sectional drawing which shows the structure of the upper board | substrate holder of FIG. It is a characteristic view which shows the result of having measured the deformation amount of the upper board | substrate holder. It is the figure which showed typically the deformation | transformation state of the upper board | substrate holding part. It is a figure which shows an example of the direction control valve which switches between an upper board | substrate and contact glass to a vacuum suction state, an air release state, or a pressurized air supply state. It is process sectional drawing which shows the manufacturing process by the manufacturing apparatus of the optical recording medium based on the 5th Example of this invention. It is a figure which shows the other example of the air blowing mechanism of FIG. It is the schematic which shows the mode of UV adhesive coating by a spin coat method. It is a figure which shows the conventional bonding process. It is a figure which shows the mode of spreading of UV adhesive agent. It is process sectional drawing which shows the bonding process with respect to a board | substrate with some curvature.

Explanation of symbols

11; Upper substrate, 12; Lower substrate holder, 13; Upper substrate holder,
14; lifting mechanism, 15; center boss, 16; pulse motor,
17; UV lamp, 18; adhesive application nozzle, 41; plunger pump,
51; moving stage, 61; pulse motor, 62, 64; motor driver,
63; a pulse motor for rotating the lower substrate; 65; a two-axis motor controller;
66; host device, 91; parallelism adjustment mechanism, 92; sensor,
93; Spot UV lamp, 96; Air spray mechanism,
99; Image sensor for detection of spread, 101; Lower substrate, 104; UV adhesive.

Claims (23)

A liquid UV curable adhesive is applied between the upper substrate and the lower substrate in an annular shape, spread and then irradiated with UV light to cure the UV curable adhesive and bond the upper substrate and the lower substrate together. In the method for manufacturing an optical recording medium,
A predetermined amount of the ultraviolet curable adhesive is annularly applied to the lower substrate to form an adhesive layer, and the distance between the substrates is made equal to the desired thickness of the adhesive layer while maintaining the upper and lower substrates straightened. A method of manufacturing an optical recording medium, comprising controlling the positioning of the upper substrate to a position. A liquid UV curable adhesive is applied between the upper substrate and the lower substrate in an annular shape, spread and then irradiated with UV light to cure the UV curable adhesive and bond the upper substrate and the lower substrate together. In the method for manufacturing an optical recording medium,
The upper substrate and the lower substrate to be bonded are pressed with a predetermined thrust, the stopped position is set as the origin position, and a predetermined amount of the UV curable adhesive is applied to the lower substrate in an annular shape to form an adhesive layer. A method of manufacturing an optical recording medium, comprising: controlling the positioning of the upper substrate from the origin position to a position where the distance between the substrates is equal to a desired thickness of the adhesive layer while maintaining correction of the substrates. A liquid UV curable adhesive is applied between the upper substrate and the lower substrate in an annular shape, spread and then irradiated with UV light to cure the UV curable adhesive and bond the upper substrate and the lower substrate together. In the method for manufacturing an optical recording medium,
A predetermined amount of the UV curable adhesive is applied to the lower substrate in an annular shape, and the distance between the substrates is made equal to the desired thickness of the adhesive layer while keeping the upper substrate and the lower substrate straightened. Positioning and a contact space state generated between the upper substrate holder that holds the upper substrate and the upper substrate are a vacuum suction state in which the upper substrate is sucked, an air release state, or the upper substrate holder and the upper substrate. A method of manufacturing an optical recording medium, wherein the spread of the ultraviolet curable adhesive is controlled by switching to either a compressed air supply state in which compressed air is supplied between the substrate and the substrate, and changing the substrate gap.   4. The method of manufacturing an optical recording medium according to claim 3, wherein ultraviolet rays are irradiated spotwise in order to cure the ultraviolet curable adhesive in a limit area that defines a spread range of the ultraviolet curable adhesive.   When the upper substrate and the lower substrate are bonded together and the ultraviolet curable adhesive is spread, the ultraviolet curable adhesive protrudes from the outer peripheral edge of the bonded upper substrate and the lower substrate. 4. The method of manufacturing an optical recording medium according to claim 3, wherein a contact space state generated between the upper substrate holder and the upper substrate is switched in accordance with a detection result by a sensor to be detected. A liquid UV curable adhesive is applied between the upper substrate and the lower substrate in an annular shape, spread and then irradiated with UV light to cure the UV curable adhesive and bond the upper substrate and the lower substrate together. In the method for manufacturing an optical recording medium,
A predetermined amount of the UV curable adhesive is applied to the lower substrate in an annular shape, and the distance between the substrates is made equal to the desired thickness of the adhesive layer while keeping the upper substrate and the lower substrate straightened. When positioning and spreading the ultraviolet curable adhesive, compressed air is blown from the outer periphery of the bonded upper substrate and the lower substrate toward the boundary between the upper substrate and the lower substrate. A method for producing an optical recording medium.   Compressed air is blown toward the boundary between the upper substrate and the lower substrate in accordance with the detection result of the sensor that detects the protrusion of the UV curable adhesive from the outer peripheral edge of the bonded upper substrate and the lower substrate. The method of manufacturing an optical recording medium according to claim 6, wherein the timing and the air volume are controlled. A liquid ultraviolet curable adhesive is applied between the upper substrate and the lower substrate in an annular shape from the nozzle, and after spreading, the ultraviolet curable adhesive is cured by irradiating with ultraviolet light to bond the upper substrate and the lower substrate. In the manufacturing apparatus of the optical recording medium to be bonded,
A lower substrate holder for adsorbing and holding substantially the entire surface of the lower substrate to a flat surface;
An upper substrate holder for adsorbing and holding substantially the entire surface of the upper substrate placed in parallel at the same center as the lower substrate holder;
An elevating mechanism that elevates and lowers the upper substrate holder while maintaining parallel to the center of the lower substrate holder;
A controller for controlling the position of the lifting mechanism,
A predetermined amount of the UV curable adhesive is annularly applied to the substrate to form an adhesive layer, and the distance between the substrates becomes equal to the desired thickness of the adhesive layer while maintaining the upper and lower substrates straightened. An apparatus for manufacturing an optical recording medium, wherein the controller controls the positioning of the upper substrate holder by the elevating mechanism to a position. A liquid ultraviolet curable adhesive is applied between the upper substrate and the lower substrate in an annular shape from the nozzle, and after spreading, the ultraviolet curable adhesive is cured by irradiating with ultraviolet light to bond the upper substrate and the lower substrate. In the manufacturing apparatus of the optical recording medium to be bonded,
A lower substrate holder for adsorbing and holding substantially the entire surface of the lower substrate to a flat surface;
An upper substrate holder for adsorbing and holding substantially the entire surface of the upper substrate placed in parallel at the same center as the lower substrate holder;
An elevating mechanism that elevates and lowers the upper substrate holder while maintaining parallel to the center of the lower substrate holder;
A controller for controlling the position of the lifting mechanism,
The upper substrate and the lower substrate to be bonded are held by the upper substrate holder and the lower substrate holder, respectively, and the upper substrate and the lower substrate are pressed with a predetermined thrust, the stopped position is set as the origin position, and a predetermined amount of the UV curing is performed. An adhesive layer is formed by applying a mold adhesive to the lower substrate in an annular shape, and the origin position is set to a position where the distance between the substrates becomes equal to the desired thickness of the adhesive layer while maintaining the correction of the upper substrate and the lower substrate. An apparatus for manufacturing an optical recording medium, wherein positioning of the upper substrate holder by the elevating mechanism is controlled by the controller. When the volume of the UV curable adhesive is V, the thickness of the UV curable adhesive layer is h, the inner radius is R1, and the outer radius is R2, the volume is V = πh (R2 ² −R1 ² ). The optical recording medium manufacturing apparatus according to claim 8, wherein the ultraviolet curable adhesive is discharged. When Rc is a radial position corresponding to the application position of the nozzle when discharging the ultraviolet curable adhesive, R1 is an inner radius of the adhesive layer to be formed, and R2 is an outer radius, Rc = √ (( The apparatus for producing an optical recording medium according to claim 8 or 9, wherein the ultraviolet curable adhesive is discharged at a radial position of R1 ² + R2 ² ) / 2).   The optical recording medium manufacturing apparatus according to claim 8 or 9, wherein discharge control of the ultraviolet curable adhesive is performed by a plunger pump driven by an air cylinder.   The optical recording medium manufacturing apparatus according to claim 12, wherein the plunger pump is driven by a pulse motor and a ball screw.   A pulse motor that rotationally drives the lower substrate holder and a rotation control unit that controls the pulse motor to rotate at a constant speed are provided, and the pulse motor is controlled by the rotation control unit to control the lower substrate holder. The apparatus for manufacturing an optical recording medium according to claim 8 or 9, wherein the optical recording medium is rotated at a constant speed.   The optical recording medium manufacturing apparatus according to claim 13 or 14, wherein the pulse motor that performs discharge control of the ultraviolet curable adhesive and the pulse motor that performs rotation control of the lower substrate holder are biaxially controlled. .   The optical recording medium manufacturing apparatus according to claim 8 or 9, wherein an air passage is provided on an outer diameter of a center boss at a center of the lower substrate holder.   10. The apparatus for manufacturing an optical recording medium according to claim 8, wherein the upper substrate or the lower substrate is rotated at a low speed at which centrifugal force does not act while the ultraviolet curable adhesive is spread. A liquid ultraviolet curable adhesive is applied between the upper substrate and the lower substrate in an annular shape from the nozzle, and after spreading, the ultraviolet curable adhesive is cured by irradiating with ultraviolet light to bond the upper substrate and the lower substrate. In the manufacturing apparatus of the optical recording medium to be bonded,
A lower substrate holder for adsorbing and holding substantially the entire surface of the lower substrate to a flat surface;
An upper substrate holder for adsorbing and holding substantially the entire surface of the upper substrate placed in parallel at the same center as the lower substrate holder;
An elevating mechanism that elevates and lowers the upper substrate holder while maintaining parallel to the center of the lower substrate holder;
A controller for controlling the position of the lifting mechanism;
A contact space state generated between the upper substrate holder and the upper substrate is a vacuum suction state in which the upper substrate is sucked, an air release state, or compressed air is supplied between the upper substrate holder and the upper substrate. Contact space state switching means for switching to any of the compressed air supply state,
An apparatus for manufacturing an optical recording medium, wherein the spread of the ultraviolet curable adhesive is controlled by changing a substrate gap. A liquid ultraviolet curable adhesive is applied between the upper substrate and the lower substrate in an annular shape from the nozzle, and after spreading, the ultraviolet curable adhesive is cured by irradiating with ultraviolet light to bond the upper substrate and the lower substrate. In the manufacturing apparatus of the optical recording medium to be bonded,
A lower substrate holder for adsorbing and holding substantially the entire surface of the lower substrate to a flat surface;
An upper substrate holder for adsorbing and holding substantially the entire surface of the upper substrate placed in parallel at the same center as the lower substrate holder;
An elevating mechanism that elevates and lowers the upper substrate holder while maintaining parallel to the center of the lower substrate holder;
A controller for controlling the position of the lifting mechanism;
An air blowing mechanism that blows compressed air from the outer periphery of the bonded upper substrate and the lower substrate toward the boundary between the upper substrate and the lower substrate when the ultraviolet curable adhesive is spread. And
An apparatus for manufacturing an optical recording medium, comprising: controlling spreading of the ultraviolet curable adhesive at an outer peripheral end portion in a gap between the bonded upper substrate and lower substrate.   19. The apparatus for producing an optical recording medium according to claim 18, further comprising a spot UV lamp that irradiates ultraviolet rays spotwise in order to cure the ultraviolet curable adhesive in a limit area that defines a spread range of the ultraviolet curable adhesive.   When the upper substrate and the lower substrate are bonded together and the ultraviolet curable adhesive is spread, the ultraviolet curable adhesive protrudes from the outer peripheral edge of the bonded upper substrate and the lower substrate. The optical recording medium manufacturing apparatus according to claim 19, further comprising a sensor for detecting, and controlling an air blowing timing and an air volume by the air blowing mechanism in accordance with a detection result of the sensor.   The optical recording medium manufacturing apparatus according to claim 19, wherein the air blowing mechanism is configured by arranging a plurality of air nozzles in an annular shape. The optical recording medium manufacturing apparatus according to any one of claims 19 to 22, wherein the air blowing mechanism or the spot UV lamp, and the bonded upper substrate and lower substrate are relatively rotated.

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