JP5108399B2 - Disk substrate transport mechanism, recording medium disk, and recording medium disk manufacturing method - Google Patents

Description

The present invention relates to an optical information recording medium such as an optical disk, a disk substrate transport mechanism used for manufacturing a magnetic recording medium, a recording medium disk, and a manufacturing method of the recording medium disk .

  Optical discs made by bonding two light-transmitting substrates are already manufactured and sold in optical discs that use laser wavelength light to read recorded information, write information, or erase information. . DVDs and laser discs are examples. This consists of two light-transmitting substrates, a reflecting layer, an adhesive layer, and a printing layer. PC (polycarbonate) and PMMA (acrylic resin) are used as the material of the light-transmitting substrate, and Au is used as the reflecting layer. , Ag, Al alloys, etc., and UV curable adhesives are used as adhesives.

  In addition, the radical UV method most frequently employed as a conventional optical disc laminating method is a radical UV on a predetermined concentric circle of the optical disc information substrate 1 (having a single plate on which information is recorded, a recording layer and a reflective layer). Adhesive is dropped by a dispenser, and a cover substrate (a transparent single plate to be a cover) is placed on the information substrate 1, and then the excess adhesive is shaken off at a predetermined rotation speed and rotation time. The adhesive is cured to obtain a bonded substrate.

Here, an outline of an example of a conventional radical UV type disk bonding method will be described.
In particular, here, as an example, an example in which two or more discs such as a two-layer reproduction disc or a two-layer recording disc are bonded together is shown. For convenience, in a single-sided light-incident two-layer disc, the lower substrate (disk) with the light incident surface facing downward is called the La substrate, and the upper substrate (disk) is called the Lb substrate.

  In the bonding process, the UV curable adhesive between the La substrate and the Lb substrate is usually cured by UV irradiation (ultraviolet irradiation) from above, so that the La substrate capable of transmitting light up to the adhesive faces upward. The disk is conveyed so that That is, the Lb substrate is first placed on the stage (spin table) of the spin coater with the barrier film sputtered surface (light incident surface side) facing up. Next, while rotating the stage at a rotation speed of about several tens of rpm, a UV curable adhesive (viscosity is about 500 cp) is dropped concentrically on a circumference of about 30 mm from the center of the Lb substrate by a dispenser. Next, the La substrate is overlapped with the Lb substrate with the light incident surface side up to form a superposed substrate. Thereafter, the stage is rotated at a rotational speed of several hundred to several thousand rpm to extend the adhesive to the end of the disk. Then, this superposition | polymerization board | substrate is moved to a light irradiation stage, an adhesive agent is hardened by ultraviolet irradiation, and it is set as a bonded type optical disk.

  At this time, if there are burrs (standing burrs) standing on the bonding surface side at the outer peripheral edge of the bonding surface side of the La substrate and Lb substrate used for bonding, the standing burrs collide with the opposing substrates, or the standing burrs facing each other. They collide with each other and bubbles are generated.

  In particular, when two or more disks such as a two-layer reproduction disk or a two-layer recording disk are bonded to each other, the thickness of the adhesive layer is limited, so that the height of the burrs of the substrates to be bonded needs to be kept small. For example, in the case of a single-layer disc without restriction, the thickness of the adhesive layer can be set as thick as 80 to 120 μm, even if a large burr stands, but it is 45 to 55 μm in DVD + R DL, HD-R DL In the two-layer disc, which is limited in terms of thickness by calculating the focal length from 22 to 28 μm and the Lb substrate, the burr height on one side of the La substrate and the Lb substrate exceeds the adhesive layer thickness, of course. Considering that the burrs come into contact with each other, the thickness of the adhesive layer should not exceed the height obtained by adding the burrs of the La and Lb substrates. Specifically, in the above DVD + R DL double layer disc, when the burr heights of both the La substrate and the Lb substrate are added to exceed 40 μm, a collision of standing burrs starts to occur, and the mechanical properties of the bonded disc deteriorate. And the generation of bubbles in the adhesive layer begins.

  After applying, the adhesive liquid for bonding is spun off by the table rotation and becomes a thin film as it continues to rotate, but when the burr hits at the outer edge, the substrate may approach the height of the standing burr. The liquid that is thinly spread on the inner peripheral side cannot be filled between the open substrates at the outer peripheral end, and air bubbles with a size of 50 μm to 1.5 mm that can be easily confirmed visually instead of the liquid Will occur.

  Here, the reason why the above-described standing burr is formed will be described. The disk substrate is formed by a mold having a stamper attached thereto. In order to prevent distortion of the attached stamper, it is necessary to provide a certain amount of clearance between the stamper and the cab ring. For this reason, a burr (lateral burr) extending in the radial direction is formed in an annular shape at the outer peripheral end edge where the stamper surface and the outer peripheral end surface of the disk substrate intersect.

  In addition, a mechanism for pre-feeding disk substrates arranged at regular intervals by screw conveyance as shown in FIG. 4 of Patent Document 1 and Patent Document 2 at a constant speed is used in a cooling process after molding and an annealing process after coloring. ing. When production is performed using a conventional DVD +/- R DL device equipped with this mechanism, consideration should be given to the burr standing on the outer periphery of the disc on the stamper side (side to be bonded) after the screw is transported. Since this is not done, the burr height changes greatly before and after screw conveyance. That is, the horizontal burr extending in the radial direction at the stamper side outer peripheral end edge of the disk substrate stands on the stamper side after the conveyance is finished, so that the burr height is increased. This is a state where the substrate temperature is still close to the mold temperature of 110 to 130 ° C. at the initial stage of molding cooling, and the substrate and the burr part itself are softened by being exposed to a temperature of 80 to 100 ° C. even during annealing. For this reason, it can be said that the burr is easily raised when the receiving screw is swung on the surface facing the burr. This phenomenon is particularly remarkable when the disk substrate is transported with the stamper surface facing the transport direction (details will be described later).

Japanese Patent No. 3625279 JP 2002-245692 A

The present invention has been made in view of the above-described problems in the prior art, and a disc capable of suppressing the occurrence of standing burrs that generate bubbles at the outer peripheral edge of the disc while utilizing most of the configuration of the conventional mechanism. It is an object of the present invention to provide a substrate transport mechanism, a recording medium disk, and a recording medium disk manufacturing method .

This invention provided in order to solve the said subject is invention of the following (1)-(11). (1) An outer peripheral end portion of a disk substrate formed by a mold is supported by a guide groove spirally formed on each of a plurality of screw shafts, and the screw substrate is rotated to convey the disk substrate in one direction. In the disk substrate transport mechanism, the guide groove includes a front wall in the transport direction, a rear side wall in the transport direction, and a bottom surface that is an inclined surface in which the groove deepens from the rear to the front in the transport direction. Substrate transport mechanism.
(2) The disc substrate transport mechanism according to (1), wherein the height difference of the bottom surface is 100 μm or more.
(3) The outer peripheral end of the disk substrate formed by the mold is supported by a guide groove spirally formed on each of the plurality of screw shafts, and the disk substrate is conveyed in one direction by rotating the screw shaft. In the disk substrate transport mechanism, the guide groove includes a front wall in the transport direction, a rear side wall in the transport direction, and a bottom surface having a recess at a front end in the transport direction.
(4) The disk substrate transport mechanism according to (3), wherein the depth of the concave portion is 100 μm or more.
(5) An outer peripheral end of a disk substrate formed by a mold is supported by a guide groove spirally provided on each of a plurality of screw shafts, and the screw substrate is rotated to convey the disk substrate in one direction. In the disk substrate transport mechanism, the guide groove includes a front side wall in the transport direction, a rear side wall in the transport direction, and a bottom surface that is an inclined surface in which the groove deepens from the front toward the rear in the transport direction. Substrate transport mechanism.
(6) The disk substrate transport mechanism according to (5), wherein an inclination angle formed by a bottom surface of the guide groove with respect to an axial direction of the screw shaft is 5 to 65 °.
(7) Said (1)-(6) characterized by the angle which the said conveyance direction front side wall makes with respect to the surface orthogonal to the axial direction of the said screw shaft is smaller than the angle which the said conveyance direction rear side wall makes. The disc substrate transport mechanism according to any one of the above.
(8) The width of the bottom surface of the guide groove is (the thickness of the disk substrate + 10) μm or more and (the thickness of the disk substrate + 500) μm or less. The disk substrate transport mechanism according to any one of the above.
(9) The disk substrate heat treatment apparatus according to any one of (1) to (8), further including a heating unit, wherein the disk substrate is heat-treated while being conveyed.
(10) The disk substrates transported by the disk substrate transport mechanism according to any one of (1) to (9) are bonded together, and the horizontal burrs of the transported disk substrate are bonded together. recording medium disk, wherein facing the outer peripheral end face direction of the conveyed disk substrate even after.
(11) A method for manufacturing a recording medium disk, comprising a step of transporting a disk substrate by the disk substrate transport mechanism according to any one of (1) to (9).

According to the first aspect of the present invention, when the disk substrate is transported with the stamper surface directed in the transport direction, the edge A at the outer peripheral end of the stamper side of the disk substrate where the horizontal burr has occurred is guided by the screw shaft. It is received by point contact at the front side wall portion in the conveying direction of the groove. For this reason, a space is provided between the outer peripheral end edge A and the bottom surface of the guide groove, and the horizontal burr is tilted in a direction (outer peripheral end surface side) that is not a stamper surface of the disk substrate with conveyance (rotation of the screw shaft). It is. Therefore, the burr height on the stamper surface side of the disk substrate at the time of bonding can be suppressed.
Similarly, according to the third aspect of the present invention, when the disk substrate is transported with the stamper surface facing the transport direction, the edge A at the outer peripheral end of the stamper side of the disk substrate in which the horizontal burr is generated is provided on the screw shaft. The guide groove is received by point contact at the front side wall portion (upper end portion of the recess) in the conveying direction. Accordingly, in the same manner as described above, the burr height on the stamper surface side of the disk substrate at the time of bonding can be suppressed.
According to the fifth aspect of the present invention, when the disk substrate is transported with the stamper surface facing the transport direction, the edge A at the outer peripheral end of the stamper side of the disk substrate where the horizontal burr has occurred is guided by the screw shaft. The groove is received at the front side wall in the conveyance direction and the corner (corner portion) of the bottom surface. Accordingly, in the same manner as described above, the burr height on the stamper surface side of the disk substrate at the time of bonding can be suppressed.
According to the invention of Claims 2, 4, and 6, it is possible to provide a sufficient space for releasing the burr on the outer peripheral end face side. As a result, the horizontal burrs that have been tilted toward the outer peripheral end face are not received by the bottom of the groove and will not stand up again, and the burr height on the stamper surface side of the disk substrate during bonding is stably suppressed. be able to.
The guide groove should be made as wide as possible so that the screw shaft length is not extended within the limited substrate pitch, and the inclined surface of the guide groove and the disc substrate are not easily rubbed when the substrate is inserted into the guide groove. However, according to the invention of claim 7, by setting the angle of the front side wall in the transport direction from the angle of the rear side wall in the transport direction, the screw shaft length can be increased without extending the screw shaft length. By opening the angle, the guide groove can be widened. Furthermore, by obtaining the effect of making the horizontal burr easy to fall in the direction (outer peripheral end surface side) that is not the stamper surface, the stamper surface side burr height at the time of bonding can be effectively suppressed.
Further, for example, the disk substrate is transported supported by three screw shafts arranged at the left / right / lower positions of the standing disk substrate, but the guides provided on the three screw shafts are supported. If the disk substrate is swallowed without the parallelism of the grooves, it will cause surface blurring of the substrate. However, it is difficult to adjust strictly following the parallelism to the μm level. According to the eighth aspect of the present invention, the width of the bottom surface portion of the guide groove is set to be several tens to several hundreds μm larger than the thickness of the disk substrate to be conveyed, so that the stress on which the disk substrate is sandwiched is eliminated to stabilize the substrate surface blur. be able to. Furthermore, as another effect, it is possible to prevent the occurrence of deterioration of birefringence at the outer peripheral edge of the substrate by eliminating the stress by which the disk substrate is sandwiched.
Further, according to the invention of claim 9, the substrate is softened by performing the heat treatment by the heating means. However, since the horizontal burr is tilted to the outer peripheral end surface side of the disk substrate as described above, the standing burr is generated. And the substrate can be transported.
According to the invention of claim 10, it is possible to provide a recording medium disk bonded without generating bubbles at the outer peripheral end.
According to the invention of claim 11, it is possible to provide a method for manufacturing a recording medium disk that can suppress the burr height on the stamper surface side of the disk substrate at the time of bonding.

The disk substrate transport mechanism and the apparatus using the disk substrate transport mechanism according to the present invention will be described below.
FIG. 1 is a schematic diagram showing a configuration example of an integrated production line for optical discs using a disc substrate transport mechanism according to the present invention.
In FIG. 1, reference numerals 1a and 1b denote molding machines. The molding machine 1a molds the disk substrate L0, and the molding machine 1b molds the disk substrate L1. The molded disk substrates L0 and L1 are transferred to the disk substrate cooling device 3 by the transfer means 2, respectively. The disk substrate cooling device 3 is for cooling the disk substrates L0 and L1 that have just been formed to a high temperature to near room temperature, and the disk substrates L0 and L1 are vertically arranged using the disk substrate transport mechanism of the present invention. Transport. Details will be described later.

  Of the two disk substrates L0 and L1 cooled by the disk substrate cooling device 3, one disk substrate L0 is transferred to the aging unit 7, and the other disk substrate L1 is transferred to the film forming device 6 by the turntable 5. After the total reflection film is formed, the aging unit 7 is transferred. The aging unit 7 is for stabilizing the temperature of the disk substrate before applying the dye, and uses the disk substrate transport mechanism of the present invention to transport the disk substrate vertically. A blower for sending air controlled at a constant temperature is mounted on the upper part of the aging unit 7.

  Subsequently, the two disk substrates L0 and L1 are transferred to the dye spinner 9 by the conveyor 8 and the transfer arm, respectively. The dye spinner 9 is for applying a dye on the surface of a disk substrate and forming a uniform dye film by a spin coating method. In order to shorten the processing time, a plurality of dye spinners 9 may be arranged and processed in parallel. The disk substrate on which the dye film is formed is transferred to the cleaning spinner 10, and the dye attached to the end surface and the back surface of the disk substrate is cleaned.

  The cleaned disk substrates L0 and L1 are returned to the conveyor 8 and transferred to the disk substrate heat treatment apparatus 50 using the disk substrate transport mechanism of the present invention. Details of the disk substrate heat treatment apparatus 50 will be described later.

  The heat-treated two disk substrates L0 and L1 are respectively transferred to the film forming apparatus 12 by the turntable 11, and a semi-transmissive film is formed on the disk substrate L0, and a protective reflective film is formed on the disk substrate L1.

  The two disk substrates L0 and L1 thus formed are transported to the turntable 21, while one of the disk substrates L1 is coated with an adhesive by an adhesive discharge nozzle 23, and the other disk substrate L0 is an inversion arm. The two sides of the disc substrate are overlapped by the laminating device 24.

  The superimposed disk substrates are transferred alternately to the spinner 25, and the adhesive film thickness between the disk substrates is made uniform by high speed rotation and bonded. Next, the disk substrate after high-speed rotation is conveyed to the ultraviolet curing device 27 by the UV table 26, and the adhesive between the disk substrates is cured by irradiating the disk substrate with ultraviolet rays. Thereafter, the disk substrate is inspected, and the manufacturing process is completed.

  Next, with reference to FIGS. 2A and 2B, a specific example of transferring a disk substrate molded from the molding machine 1a or 1b to the disk substrate cooling device 3 will be described. The transfer means 2 includes a drive unit 2a, a transfer arm 2b operated by the drive unit 2a, and a suction unit 2c provided on the transfer arm 2b.

  First, disc substrates are taken out from the molding machine 1a or 1b one by one by a disc substrate take-out means (not shown). The transfer means 2 pivots in the direction indicated by the arrow at the same time as receiving the disk substrate by suction holding at the position P in FIG. When the disk substrate reaches the mounting position of the disk substrate cooling device 3, the disk substrate adsorption of the transfer arm 2b is released, and the tip of the transfer arm 2b is retracted, whereby the disk substrate is moved to the disk substrate cooling device 3. Transfer.

  In the disk substrate cooling device 3, a set of three screw shafts 3a constitutes a disk substrate transport mechanism. The screw shafts 3a all have the same structure, and have a spiral guide groove 3b formed on a straight shaft at a constant pitch as shown in FIG. The guide groove 3b includes a side wall and a bottom surface, and has a depth and a width such that the outer peripheral end portion of the disk substrate L0 (L1) does not easily deviate when entering the inside. The three screw shafts 3a are preferably arranged at the vertices of an isosceles triangle, and are arranged so that the guide grooves 3b of the three screw shafts 3a receive the circumferential portion of the disk substrate L0 (L1) evenly. Has been.

  These three screw shafts 3a are rotated in the direction of the arrow at a constant speed by a drive unit (not shown) (FIG. 3B). As a result, the disk substrate L0 (L1) placed upright on the three screw shafts 3a is advanced a certain distance until the next disk substrate is transferred by the transfer means 2 according to the guide groove 3b. Yes. In this way, when a predetermined number of disk substrates L0 (L1) are sequentially forwarded and sent to a predetermined position in the column, the transfer means 4 transfers them to the next process.

  Next, a disk substrate heat treatment apparatus using the disk substrate transport mechanism of the present invention will be described. This disk substrate heat treatment apparatus is incorporated in the optical disk production line described above, and improves and stabilizes the quality of the optical disk as a disk substrate L0, L1 formed with a dye film and cleaned, and stabilizes the reproduction signal. It is the apparatus which performs the heat processing for.

FIG. 4 shows a configuration diagram of the disk substrate heat treatment apparatus of the present invention. 4A is a view from the side of the apparatus, and FIG. 4B is a view from the top of the apparatus.
In these drawings, a heat treatment chamber 51 serving as a drying furnace is composed of two side wall plates 52 and 53 and two partition plates 54 and 55 similar thereto, which are a temperature raising unit 56, a constant temperature holding unit 57, and a cooling unit 58. It is divided into two rooms. The disk substrate 60 sequentially passes through the temperature raising unit 56, the constant temperature holding unit 57, and the cooling unit 58 by the disk substrate transport mechanism 59 of the present invention. Drying is performed in the heat treatment chamber 51 to remove the organic solvent. The disk transport mechanism 59 for transporting the disk substrate 60 has the same configuration as the disk substrate transport mechanism described with reference to FIGS. 1 to 3, and includes a screw shaft 59a having a guide groove formed in a spiral shape at a predetermined pitch. 59b, 59c, and a large number of disk substrates 60 are vertically conveyed at predetermined intervals and sequentially conveyed.

  The screw shafts 59a, 59b, 59c are arranged at the corners of the isosceles triangle with the screw shaft 59b as the apex, and the screw shafts 59a, 59b, 59c are rotated by the guide grooves formed in them. The disk substrate 60 is sequentially fed forward while maintaining a predetermined interval.

  In the disk substrate heat treatment apparatus 50, as indicated by the arrows in the figure, hot air is blown from the blow holes formed in the blow plate 61a in the temperature raising portion 56 and the constant temperature holding portion 57, and air or nitrogen at room temperature or lower is blown in the cooling portion 58. Such a gas is ejected from the blowing plate 63a. The hole through which the hot air is blown out by the temperature raising unit 56 is a slit formed in the blower plate 61a. The slit is located directly above the top of the disk substrate 60 that is sequentially transferred, and the hot air is conveyed from the slit in the conveying direction. Is supplied vertically, that is, along the circular surface of the disk substrate 60.

  The disk substrate 60 set up at such an interval passes through the temperature raising unit 56 in about 1 minute, but is heated from 50 ° C. to a temperature lower than the softening temperature of the disk substrate (eg, 110 to 130 ° C.) by a heater (not shown). Each of the disk substrates 60 rises to a predetermined temperature lower than the softening point temperature of the disk substrate at the entrance of the next constant temperature holding portion 57 by ejecting the gas thus formed from the slit of the blowing plate 61a at a predetermined wind speed. .

  Next, the constant temperature holding unit 57 does not raise or lower the temperature of each disk substrate 60 that has been heated to a predetermined temperature by the temperature raising unit 56, but keeps the temperature at the set temperature to maintain the organic dye of the disk substrate 60. The organic solvent is almost completely removed from the thin film.

  As described above, the disk substrate 60 is dried while being sequentially transported by the disk substrate transport mechanism 59 in the constant temperature holding unit 57, and is sent to the cooling unit 58 through the partition plate 55. The structure of the cooling unit 58 is substantially the same as that of the temperature raising unit 56, except that the temperature of the gas ejected from the slit of the blowing plate 63a is about room temperature. Thereby, in the cooling part 58, it falls from the said preset temperature to about room temperature.

  Here, details of the disk substrate transport mechanism 59 will be described with reference to FIGS. FIG. 5 shows screw shafts 59a, 59b, 59c and bearing members 65, 65 ′ that rotatably support one end of each of the screw shafts 59a ′, 59b ′, 59c ′ provided in parallel with the same structure. The support members 65 (65 ′) are respectively provided at both ends of the screw shaft. In FIG. 5, two disk substrates 60, 60 'in two lines are simultaneously heat-treated and dried. The screw shafts 59a, 59b, and 59c are fixed to the inner rings of radial bearings 66a, 66b, and 66c in which outer rings are attached to the support member 65, and are freely rotatable with respect to the support member 65. The same applies to the screw shafts 59a ', 59b', 59c '. The screw shafts 59a, 59b, 59c and the screw shafts 59a ', 59b', 59c 'are coupled to a drive source (not shown) via a belt (not shown).

  The support member 65 includes grooves 65b and 65c extending downward from the upper surface 65a. The groove 65b is provided with a transport arm (not shown) when the disk substrate 60 is transferred to the screw shafts 59a, 59b, 59c, and gently guides the screw shafts 59a, 59b, 59c without impacting the disk substrate 60. It is possible to place the disk substrate 60 in the groove. The groove 65c performs the same function as the groove 65b, and allows the disk substrate 60 'to be quietly placed in the respective guide grooves of the screw shafts 59a', 59b ', 59c' without receiving an impact. The shapes of the grooves 65c and 65b are not limited, and a conveying arm (not shown) enters the grooves 65c and 65b from the front side of the paper surface, so that the disk substrates 60 and 60 ′ are respectively connected to the screw shafts 59a, When placing on 59b, 59c and screw shafts 59a ′, 59b ′, 59c ′, the transport arm may not contact the inner walls of the grooves 65c, 65b.

  Here, the disk substrate transport mechanism according to the present invention adopts any one of the following Embodiments 1, 2, and 3, so that the outer periphery of the outer peripheral edge of the disk substrate L0 (L1) generates burrs. The end edge A is directed in the transport direction, and the outer peripheral end edge A is supported by the side wall of the guide groove 3b or the corner between the front side wall of the guide groove 3b in the transport direction and the inclined bottom surface to transport the disk substrate L0 (L1). It is what you do. As a result, the burr is brought down to the outer peripheral end face side of the disk substrate L0 (L1) when the side wall of the guide groove 3b or the corner of the front side wall in the conveyance direction of the guide groove 3b and the inclined bottom surface abuts. As a result, there is no adverse effect when the disk substrates are bonded together.

  In the present invention, the guide groove 3b includes a front side wall in the transport direction, a rear side wall in the transport direction, and a bottom surface that is an inclined surface in which the groove deepens from the rear to the front in the transport direction (Embodiment). 1). That is, the bottom surface of the guide groove 3b becomes an inclined surface where the groove on the outer peripheral end edge A side of the disk substrate L0 (L1) becomes deep, so that the gap between the outer peripheral end edge A and the bottom surface of the guide groove 3b is increased. A space for escaping the burr collapsed by the side wall of the guide groove 3b is provided. At this time, the height difference of the inclined bottom surface is preferably 100 μm or more so that the depth of the space for releasing the burr is 100 μm or more from the outer peripheral edge A of the disk substrate L0 (L1).

  Or the guide groove 3b consists of a conveyance direction front side wall, a conveyance direction back side wall, and the bottom face which has a recessed part in a conveyance direction front end part (Embodiment 2). That is, since the bottom surface of the guide groove 3b has a concave portion in which the groove becomes deeper on the outer peripheral end edge A side of the disk substrate L0 (L1), the guide groove 3b is interposed between the outer peripheral end edge A and the bottom surface of the guide groove 3b. A space for escaping the burr collapsed by the side wall of the groove 3b is provided. At this time, the depth of the recess is preferably 100 μm or more so that the depth of the space for releasing the burr is 100 μm or more from the outer peripheral edge A of the disk substrate L0 (L1).

  Alternatively, the guide groove 3b includes a front side wall in the transport direction, a rear side wall in the transport direction, and a bottom surface that is an inclined surface in which the groove deepens from the front to the rear in the transport direction (Embodiment 3). . That is, when the disk substrate L0 (L1) is transported by supporting the outer peripheral edge edge A at the corners between the front side wall and the inclined bottom surface in the transport direction of the guide groove 3b, the outer peripheral edge of the disk substrate L0 (L1). A space is provided between the (end face) and the inclined bottom surface of the guide groove 3b to escape the burrs that are tilted by the corners between the front side wall and the inclined bottom surface of the guide groove 3b in the conveying direction. At this time, the angle (inclination angle) formed between the inclined bottom surface of the guide groove 3b and the outer peripheral end (end surface) of the disc substrate L0 (L1) to be conveyed is preferably 5 to 65 °, and more preferably 10 It is preferably ˜28 °. The depth of the space for escaping the burr is preferably 100 μm or more on the rear side wall side in the transport direction of the guide groove 3b.

  In the first, second, and third embodiments, it is preferable that an angle formed by the front side wall in the transport direction with respect to a surface orthogonal to the axial direction of the screw shaft 3a is smaller than an angle formed by the rear side wall in the transport direction. is there. As a result, of the side walls of the guide groove 3b, the angle formed between the side wall supporting the outer peripheral edge A of the disk substrate L0 (L1) and the disk substrate L0 (L1) is the other side wall and the disk substrate a (b). Smaller than the angle between

  In the first, second, and third embodiments, the bottom width of the guide groove 3b is (the thickness of the disk substrate L0 (L1) +10) μm or more and (the thickness of the disk substrate L0 (L1) +500) μm or less. Good.

  As described above, the disk substrate L0 (L1) having undergone the disk substrate cooling apparatus 3 and the disk substrate heat treatment apparatus having the disk substrate transport mechanism according to the present invention is formed by the film formation apparatus 12, film reversal, and liquid adhesion. After the application of the agent, the two disc substrates are superposed in the disc substrate laminating apparatus 24 and bonded together through UV curing, so that an optical disc free from bubbles mixed around the outer periphery of the adhesive layer can be obtained.

Hereinafter, experimental examples performed for verifying the effects and the like of the present invention will be described.
(Experimental example 1)
First, the results of investigation on the effects of deterioration of burr height and peripheral air bubble contamination in a disk substrate heat treatment apparatus using a conventional disk substrate transport mechanism will be described.

  FIG. 7 is a schematic view of a mold cross-sectional shape. As shown in FIG. 7, due to the clearance between the stamper 41 and the cab ring 45, a horizontal burr occurs on the end surface of the disk substrate L.

  When the disk substrate L in this state is inserted into the guide groove 93b of the screw shaft as shown in FIG. 8 in the conventional disk substrate transport mechanism, the end surface of the disk substrate L is a horizontal portion on the bottom surface of the guide groove 93b as shown in FIG. It will be in the state which contacts. When the screw shaft is rotated to transport the disk substrate L in this state, the burr of the disk substrate L is tilted to the stamper surface side (bonding surface side) by the bottom surface of the guide groove 93b regardless of the traveling direction side. It stands on the main surface of the disk substrate L.

  Here, by changing the clearance between the stamper and the cab ring of the mold in FIG. 7 to change the degree of occurrence of lateral burrs, the two disk substrates L0 and L1 are pasted as they are without suppressing burrs in the subsequent process. The mixed state of the peripheral bubbles was investigated. The results are shown in Table 1. In addition, the case where the clearance between the stamper and the cavities of the mold is 17 μm is defined as (small burr) condition, and the case where the clearance is 25 μm is defined as (large burr) condition, and both the disk substrates L0 and L1 are (small burr). The combination of the conditions is the molding condition 1, the disk substrate L0 is the (large burr) condition, the combination of the disk substrate L1 is the (low burr) condition, the molding condition 2, the disk substrate L0 is the (low burr) condition, and the disk substrate L1 is the The combination of the (large burr) condition is the molding condition 3, and the standing burr height of the outer peripheral portion on the stamper surface side of the disk substrate and the peripheral bubble mixed state under each condition are investigated.

  At this time, with respect to the disk substrate L1, the transition of the burr height of the stamper side surface (bonding surface side) in the optical disk production line and the burr height at the time of bonding were investigated. Specifically, as shown in FIG. 10, the outer peripheral end portion at the position where the stamper stamp (L) is present on the stamper surface of the disk substrate L1 formed under the (small burr) condition and (large burr) condition is set to 0 deg (in the drawing). Burr height at the outer peripheral edge at each position of 45, 90, 135, 180, 225, 270, and 315 deg in the clockwise direction from the position, and annealing (heat treatment) after molding and cooling It was measured at each stage before, after annealing and before bonding. A burr height was measured using a surface roughness measuring device (DEKTAK3). The results are shown in Table 2. In addition, "-" notation in a table | surface shows unmeasured. Although an example of the disk substrate L1 is shown here, the disk substrate L0 has almost the same result.

  As shown in Table 2, it is possible to reduce the occurrence of lateral burrs by narrowing the space between the stamper 41 and the cab ring 45 in the mold structure. However, when the cab ring 45 comes close to the stamper 41, the cause of distortion of the stamper 41 is caused. Then, since the groove distortion of the disk substrate L to be formed occurs, there is a limit to the suppression of burrs in the mold. On the other hand, the present invention prevents the generation of bubbles on the outer periphery of the adhesive layer due to the influence of lateral burrs in the laminating process by suppressing the lateral burrs of the disk transport mechanism in the subsequent process without groove distortion in the molding process.

(Experimental example 2)
In a conventional disk substrate transport mechanism, a disk substrate with horizontal burrs was transported under the following transport conditions (Table 3), and the state of burr standing was investigated. That is, the direction of the stamper surface (bonding surface) when inserting the disk substrate into the guide groove of the screw shaft and the rotation of the screw shaft were changed to investigate the influence on the burr standing. FIG. 11 shows a state in which the disk substrate is inserted in the conventional groove-shaped guide groove in the case of transport conditions 1 and 3, and FIG. 12 shows the conventional groove-shaped guide groove in the case of transport condition 2 The state in which the disc substrate is inserted is shown.

  In the investigation, the burr heights at four locations (1, 2, 3, 4) on the outer peripheral edge of the disc substrate on the stamper surface side were measured for the disc substrate before and after annealing as shown in FIG. The results are shown in Table 4. Table 4 (a) shows the measurement results before annealing (before disk substrate conveyance), and Table 4 (b) shows four locations (1, 2, 3, 4 for each of the conveyance conditions 1 to 3 after annealing (after disk substrate conveyance). ) Measurement results.

  As a result, when the horizontal burrs are on the side opposite to the disk traveling direction in the guide groove, the burrs fall down and tend to stand on the stamper surface side. On the other hand, if there is a horizontal burr on the disk traveling direction side in the guide groove, there will be a variation between the part where the burr stands and the part where it does not stand depending on the angular position in the circumferential direction. The part where erupted had a higher burr height than when the stamper surface was placed in the opposite direction to the traveling direction.

  To summarize the above, in the case of the conveyance condition 1 (normal conveyance), since the lateral burr portion is on the side toward the traveling direction, the burr was tilted back and forth with respect to the traveling direction. Moreover, the burr that fell in the traveling direction was much larger than the reverse conveyance. Next, in the case of the conveyance condition 2 (reverse conveyance), the lateral burr spot is on the rear side with respect to the traveling direction. Moreover, in the case of the conveyance condition 3, it was a repetition of forward rotation and counter-rotation of the screw shaft, both elements of the conveyance conditions 1 and 2 were entered, and the burr in the conveyance condition 1 was somewhat crushed. As described above, the relationship between the insertion direction of the disc substrate stamper surface into the guide groove and the standing of burrs is known, and it has been found that it is difficult to alleviate the generation of outer peripheral burrs in the current screw conveyance.

(Experimental example 3)
From the results obtained in Experimental Example 2, the shape of the guide groove was improved with the aim of suppressing burrs, and the contact state between the outer peripheral edge of the disk substrate and the guide groove was changed.
FIG. 14 shows a first modification of the guide groove shape of the screw shaft for suppressing burrs (Example 1). The bottom surface of the guide groove 3b1 is an inclined surface in which the groove on the stamper surface (outer peripheral end edge A) side of the disk substrate L is deepened, so that the guide groove is provided between the outer peripheral end edge A and the bottom surface of the guide groove 3b1. It is possible to secure a space for escaping burrs that have been knocked down by the side wall 3b1.

Here, a molded substrate (before burr) for the disk substrate L0 under the molding condition 2 in Experiment Example 1 (before annealing) and a molded substrate (before the burr) under the condition (large burr) for the disk substrate L1 under the molding condition 3 were used. The maximum height from the substrate end face of the horizontal burr before screw conveyance was approximately 100 to 130 μm, so that the space for releasing the burr is preferably 100 μm or more, more preferably 200 μm or more. is there. That is, the bottom surface is inclined so that the height difference D1 of the bottom surface is 100 μm or more, more preferably 200 μm or more, which corresponds to the burr height so that the returned burr does not return.
When the stamper surface from which the horizontal burrs of the disk substrate emerge is placed in the guide groove in the reverse direction from the disk traveling direction, the same effect can be obtained by reversing the inclination direction of the bottom surface of the guide groove 3b1.

  Next, FIG. 15 shows a second modification of the guide groove shape of the screw shaft that suppresses burrs (Example 2). It is assumed that the bottom surface of the guide groove 3b2 has a concave portion in which the groove is deep on the stamper surface (outer peripheral edge A) side of the disk substrate L, whereby the peripheral edge between the outer peripheral edge A and the bottom surface of the guide groove 3b2. It is possible to secure a space for releasing the burrs that have been knocked down by the side wall of the guide groove 3b2.

Also in this case, it is assumed that the depth D2 of the recess is preferably 100 μm or more corresponding to the burr height, more preferably 200 μm or more so that it escapes to the bottom deep side so that the burr that has tilted the recess does not return.
In the case where the stamper surface where the horizontal burrs of the disk substrate emerge is placed in the guide groove in the reverse direction from the disk traveling direction side, it is the same if the arrangement of the recesses on the bottom surface of the guide groove 3b2 is reversed from the disk traveling direction side. An effect is obtained.

  Further, of the side walls of the guide groove 3b of the screw shaft, the side wall supporting the outer peripheral end (outer peripheral end edge A) of the stamper surface of the disk substrate L and the disk substrate L (surface orthogonal to the axial direction of the screw shaft) Is preferably smaller than the angle θ2 formed between the other side wall and the disk substrate L.

  FIG. 16A shows the state (Example 3). As a burr suppressing effect, the outer peripheral edge A of the stamper surface of the disk substrate L is received by the side wall on the traveling direction side of the guide groove 3b3. At this time, the inclination of the side wall of the guide groove 3b3 is inclined in order to more reliably depress the burr. It has a standing shape. That is, it is preferable that θ1 is 5 to 25 °, θ2 is 25 to 45 °, and (θ2−θ1) is 15 to 25 °. Further, as in the case of FIG. 14, the bottom surface of the guide groove 3 b 3 is used as an inclined surface where the groove on the stamper surface (outer peripheral edge A) side of the disk substrate L becomes deep so as to prevent horizontal burr from returning. Space is secured. Further, by setting the substrate receiving portion horizontal width (groove width) of the bottom surface of the guide groove 3b3 to 650 μm with respect to the thickness 600 μm of the disk substrate L, stress is applied to the disk substrate at a high temperature immediately after annealing or molding, The shape prevents deterioration of blurring and birefringence. FIG. 16B is a specific example of the guide groove 3b1 shown in FIG.

  In the disk substrate heat treatment apparatus using the disk substrate conveyance mechanism shown in FIG. 16A, the disk substrate was conveyed at a heat treatment temperature of 85 ° C./heat treatment time of 15 minutes, and the burr height of the disk substrate before and after the conveyance was investigated. . Here, sample no. 1, No. 1 The measurement was performed 4 times for each of 2 and the results are shown in Table 5. Table 5 (a) shows the measurement results before transporting the disk substrate, and Table 5 (b) shows the measurement results after transporting the disk substrate.

  After passing through the disk substrate heat treatment apparatus by the disk substrate transfer mechanism, the height of the peripheral burr was reduced, so that standing burrs were suppressed. That is, the horizontal burr at the outer peripheral edge of the disk substrate is received (clamped) by point contact with the side wall of the guide groove on the disk traveling direction side, and is prevented from falling to the stamper surface side, which is effective as a burr countermeasure. I can say that.

  Next, the disk substrates thus obtained were bonded as disk substrates L0 and L1, and the state of peripheral edge bubble generation was investigated. As a result, it was 0/50 sheets (no bubbles were generated), and it was a result that the bonding could be stably performed without generating bubbles at a level equivalent to the molding condition 1 in Table 1.

(Experimental example 4)
From the results obtained in Experimental Example 2, the shape of the guide groove was improved with the aim of suppressing burrs, and the contact state between the outer peripheral edge of the disk substrate and the guide groove was changed.
FIG. 17 shows a fourth modification of the guide groove shape of the screw shaft for suppressing burrs (Example 4). The guide groove 3b4 includes a front side wall 3b41 in the transport direction, a rear side wall 3b43 in the transport direction, and an inclined surface (a stamper surface (outer peripheral edge A) of the disk substrate L) on which the groove becomes deeper from the front to the rear in the transport direction. An inclined bottom surface 3b42 (an angle with respect to the axial direction of the screw shaft: α) which is an inclined surface where the groove becomes shallower. As a result, a space is provided between the outer peripheral end of the disk substrate L and the bottom surface of the guide groove 3b4 so as to release the burr collapsed by the corners of the guide side wall 3b41 and the inclined bottom surface 3b42 in the conveyance direction of the guide groove 3b4. Can do.

It should be noted that the molded substrate (before burr) for the disk substrate L0 under the molding condition 2 in Experimental Example 1 (before annealing) and the molded substrate (before the burr) under the condition (large burr) for the disk substrate L1 under the molding condition 3 were used. Since the maximum height from the substrate end face of the horizontal burr before screw conveyance was approximately 100 to 130 μm, a space is provided so that the burr having a length of 100 to 130 μm can be released. In addition, an angle (inclination angle) α between the inclined bottom surface 3b42 of the guide groove 3b4 and the outer peripheral end of the disk substrate L to be conveyed is 5 to 65 °, and more preferably 10 to 28 °. As a result, the burr is tilted acutely so as to be close to the outer peripheral end portion of the disk substrate L by the corner portion of the guide groove 3b4 in the conveyance direction front side wall 3b41 and the inclined bottom surface 3b42.
When the stamper surface where the horizontal burrs of the disk substrate emerge is placed in the guide groove in the reverse direction from the disk traveling direction, the same effect can be obtained by reversing the inclination direction of the bottom surface of the guide groove 3b4.

  Further, it is preferable that the angle θ1 formed between the front side wall in the transport direction and the disk substrate L among the side walls of the guide groove 3b of the screw shaft is smaller than the angle θ2 formed between the rear side wall in the transport direction and the disk substrate L. That is, it is preferable that θ1 is 5 to 25 °, θ2 is 25 to 45 °, and (θ2−θ1) is 15 to 25 °.

  FIG. 18A shows the state (Example 5). As an effect of suppressing burr, the outer peripheral edge A of the stamper surface of the disk substrate L is received at the corner between the side wall (forward side wall in the transport direction) 3b51 of the guide groove 3b5 and the inclined bottom surface 3b52. At this time, in order to more reliably tilt the burr, the front side wall 3b51 in the transport direction of the guide groove 3b5 is inclined. Further, as in the case of FIG. 17, the bottom surface 3b52 of the guide groove 3b5 is formed as an inclined surface where the groove on the stamper surface (outer peripheral edge A) side of the disk substrate L becomes shallow so that the horizontal burr does not return. Space to escape is secured. Furthermore, by setting the substrate receiving portion horizontal width (groove width) of the bottom surface 3b52 of the guide groove 3b5 to 650 μm with respect to the thickness 600 μm of the disk substrate L, stress is applied to the disk substrate at a high temperature immediately after annealing or molding, The shape prevents the surface blurring and birefringence from deteriorating. FIG. 18B is a specific example (Example 4) of the guide groove 3b4 shown in FIG. FIG. 18C is a specific example (Example 1) of the guide groove 3b1 shown in FIG.

  In the disk substrate heat treatment apparatus using the disk substrate conveyance mechanism having the guide groove 3b4 shown in FIG. 18B, the disk substrate is conveyed at a heat treatment temperature of 85 ° C./heat treatment time of 15 minutes, and the disk substrate burrs before and after the conveyance are transferred. The height was investigated. Here, Example 4 was performed under these conditions, and each item was measured for three sample disk substrates. The same experiment was performed as a comparative example using the conventional condition using the disc substrate transport mechanism of Condition 1 in Experimental Example 1 and using the disc substrate transport mechanism having the guide groove 3b1 as Example 1.

Here, the substrate burr height is 4 angles (0...) At the stage before annealing and after annealing (passing through the screw of the disk substrate heat treatment apparatus) for the three disk substrates L1 and 3 under the same conditions as in Experimental Example 1. 90, 180, 270 deg) The maximum burr height at the outer peripheral edge at each position was measured.
Table 6 shows a comparison result of molding burr measurement before and after the conveyance of the disk substrate.

  As a result, in Examples 1 and 4, since the outer peripheral burr height was reduced after passing through the disk substrate heat treatment apparatus by the disk substrate transport mechanism, standing burrs were suppressed. That is, the horizontal burr at the outer peripheral edge of the disk substrate is received (clamped) at the corner between the front side wall (side wall in the disk traveling direction) of the guide groove and the inclined bottom surface (clamped). The fall is suppressed and it can be said that it is effective as a countermeasure against burr. In addition, it can be said that Example 4 has a higher burr suppression effect than Example 1.

  Next, the disk substrate obtained in Example 4 is used as the disk substrate L1, and bonded to the disk substrate L0 processed using the conventional screw of the comparative example under the same conditions as the optical disk (Example 5). The situation of occurrence was investigated. Further, an optical disk was similarly manufactured using the disk substrate obtained in the comparative example as the disk substrate L1, and investigated as a comparative example. The n number of the optical disk was 260. Here again, it was confirmed that the number of sheets was 0/260 (no bubbles were generated), and it was possible to stably perform bonding without generating bubbles at a level equivalent to molding condition 1 in Table 1.

  Next, according to the configuration of Example 4 in Table 6, the burr height before annealing of 31 to 39 μm was 0 to 1 μm after annealing, which was almost free of burrs. The relationship between the substrate burr height before and after annealing was investigated for the purpose of seeing the limit of this, and the summary is shown in FIG. In this investigation, the maximum burr height before annealing was 47 μm, but if it was less than that, the burr height was almost 0 μm after annealing. Moreover, since the burr height after annealing was controlled to 0-8 μm including variation, it was found that a high burr suppressing effect was obtained.

  In the present embodiment, an example of bonding of a single-sided light incident two-layer optical disk substrate has been described. However, the present invention is not limited to this, and a single-layer disk or high-precision bonding is required. Other varieties and processes can be similarly implemented. Moreover, not only in the disk substrate transfer mechanism (screw transfer in annealing) in the disk substrate heat treatment apparatus, but also when receiving a disk substrate as a disk substrate cooling apparatus immediately after being taken out at a high mold temperature of 120 ° C. or higher, According to the disk substrate transport mechanism of the present invention, the cavity ring having a structure that is lifted by a spring when the disk substrate is taken out raises the horizontal burrs of the disk substrate, and is also effective in suppressing the standing burrs generated on the stamper surface. Demonstrate.

It is the schematic which shows the structure of the optical disk production line using the disk board | substrate conveyance mechanism based on this invention. It is explanatory drawing of the mechanism which transfers a disk substrate to the disk substrate cooling device from the molding machine of the optical disk production line of FIG. It is explanatory drawing of a one part structure of the disc board | substrate conveyance mechanism based on this invention. It is the schematic which shows the structure of the disk substrate heat processing apparatus which concerns on this invention. It is the schematic (1) which shows the structure of the disc substrate conveyance mechanism used for the disc substrate heat processing apparatus of FIG. It is the schematic (2) which shows the structure of the disc substrate conveyance mechanism used for the disc substrate heat processing apparatus of FIG. It is sectional drawing which shows the structure of the metal mold | die for shape | molding a disc board | substrate. It is sectional drawing (1) which shows the relationship between the disc substrate and guide groove in the conventional disc substrate conveyance mechanism. It is sectional drawing (2) which shows the relationship between the disc substrate and guide groove in the conventional disc substrate conveyance mechanism. It is a figure which shows the measurement position of the burr height in the stamper surface of a disc board | substrate. FIG. 10 is a cross-sectional view showing the relationship between a disk substrate and guide grooves under transport conditions 1 and 3 in Experimental Example 2. FIG. 10 is a cross-sectional view showing the relationship between a disk substrate and guide grooves under transport conditions 2 in Experimental Example 2. It is a figure which shows the measurement location of the burr | flash standing in the circumferential direction of the disc substrate of Experimental Example 2. It is sectional drawing (1) which shows the relationship between the disc substrate and guide groove in the disc substrate conveyance mechanism of this invention. It is sectional drawing (2) which shows the relationship between the disk board | substrate and guide groove in the disk board | substrate conveyance mechanism of this invention. It is sectional drawing (3) which shows the relationship between the disk board | substrate and guide groove in the disk board | substrate conveyance mechanism of this invention. It is sectional drawing (4) which shows the relationship between the disc board | substrate and guide groove in the disc board | substrate conveyance mechanism of this invention. It is sectional drawing (5) which shows the relationship between the disc substrate and guide groove in the disc substrate conveyance mechanism of this invention. It is the figure which compared the board | substrate burr height before and behind annealing using the disc board | substrate conveyance mechanism of Example 4, and showed the burr | flash suppression effect.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Disc substrate molding machine 2 1st transfer means 3 Disc substrate cooling device 3a, 59a-59c Screw shaft 3b, 3b1, 3b2, 3b3, 3b4, 3b5, 93b Guide groove 3b41, 3b51 Transport direction front side wall 3b42, 3b52 Inclined bottom surface 3b43, 3b53 Backward side wall 3c in driving direction 3c Drive unit 4 Second transfer means 5 First turntable
6 Third transfer means 7 Second turntable
8 Reflecting film forming apparatus 9 Fourth transfer means
10 Third turntable 11 Reversing mechanism
12 Liquid adhesive supply mechanism 13 Overlay mechanism
14 Fifth transfer means 15, 16 Spinner device
17 Temporary cradle 18 Discharge chute
19 6th transfer means 20 4th turntable
21 Fifth turntable 22 Weight transport mechanism
23 Curing device 24 Reversing means
25 Electrostatic blower 26 Seventh transfer means
27 Inspection device 28 Elevating stage
29 Eighth transfer means 30 Non-defective product turntable
31 Stacker for disk substrate 32 Turntable for defective products
33 Stacker for defective products 34 Turntable for defective products
35 Defective Product Stacker 41 Stamper 42 Fixed Mirror Surface 43 Stamper Suction Air Piping 44, 47 Temperature Control Piping 45 Cavity 46 Movable Mirror Surface 47
51 Heat treatment room
52, 53 Side wall plate 54, 55 Partition plate
56 Temperature rising part 57 Constant temperature holding part 58 Cooling part 59 Disk substrate transport mechanism 60, 60 ', a, b, L ... Disk substrate 61a Blowing plate 61b of temperature rising part 56 Discharge plate 62a of temperature rising part 56a Constant temperature holding Blower plate 62b discharge plate 63a constant temperature holding unit 57 discharge plate 63a cooling plate 58 discharge plate 63b cooling plate 58 discharge plate 65 support plate 66a to 66c disk substrate transport mechanism 65 bearing 67 suction means 68 base means 69 guide rail 70 Linear drive device 71 Mounting means 72 Radial bearing 73 Bolt

Claims (11)

A disk substrate transport that supports the outer peripheral end of a disk substrate formed by a mold with a guide groove spirally formed on each of a plurality of screw shafts and transports the disk substrate in one direction by rotating the screw shaft. In the mechanism,
2. The disk substrate transport mechanism according to claim 1, wherein the guide groove includes a front side wall in the transport direction, a rear side wall in the transport direction, and a bottom surface that is an inclined surface in which the groove becomes deeper from the rear to the front in the transport direction.   The disk substrate transport mechanism according to claim 1, wherein a difference in height of the bottom surface is 100 μm or more. A disk substrate transport that supports the outer peripheral end of a disk substrate formed by a mold with a guide groove spirally formed on each of a plurality of screw shafts and transports the disk substrate in one direction by rotating the screw shaft. In the mechanism,
The disk substrate transport mechanism, wherein the guide groove comprises a transport direction front side wall, a transport direction rear side wall, and a bottom surface having a recess at a front end in the transport direction.   The disk substrate transport mechanism according to claim 3, wherein the depth of the recess is 100 μm or more. A disk substrate transport that supports the outer peripheral end of a disk substrate formed by a mold with a guide groove spirally formed on each of a plurality of screw shafts and transports the disk substrate in one direction by rotating the screw shaft. In the mechanism,
2. The disk substrate transport mechanism according to claim 1, wherein the guide groove includes a front side wall in the transport direction, a rear side wall in the transport direction, and a bottom surface that is an inclined surface in which the groove becomes deeper from the front toward the rear in the transport direction.   6. The disk substrate transport mechanism according to claim 5, wherein an inclination angle formed by a bottom surface of the guide groove with respect to an axial direction of the screw shaft is 5 to 65 degrees.   The angle which the said conveyance direction front side wall makes with respect to the surface orthogonal to the axial direction of the said screw shaft is smaller than the angle which the said conveyance direction rear side wall makes, The claim 1 characterized by the above-mentioned. Disk substrate transport mechanism.   The bottom surface width of the guide groove is (thickness of the disk substrate + 10) μm or more and (thickness of the disk substrate + 500) μm or less. Disk substrate transport mechanism.   The disk substrate transport mechanism according to claim 1, further comprising a heating unit, wherein the disk substrate is heat-treated while transporting the disk substrate. The disk substrates transported by the disk substrate transport mechanism according to any one of claims 1 to 9 are bonded together,
The recording medium disk, wherein the horizontal burrs of the transported disk substrate are directed toward the outer peripheral end surface of the transported disk substrate even after the bonding .   A method for manufacturing a recording medium disk, comprising the step of transporting a disk substrate by the disk substrate transport mechanism according to claim 1.