JP2005125746A - Mold device for molding substrate, disk substrate, and method for producing substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To secure the plane property of a disk substrate which is molded/manufactured through a peeling process while attaining the shortening of a molding cycle. <P>SOLUTION: A mold device for molding a substrate has a resistance mold release part 15 formed by doing roughening in relation to the inner surface of a mold in the shape of a surface by point collection, line collection, or the combination of them on the inner surface of the mold corresponding to the peripheral side end surface of the disk substrate 4. When the disk substrate 4 molded by packing a synthetic resin material in a substrate molding cavity 5 fitted with a stamper 7 for transfer is stripped from the stamper 7, by showing " resistance" to the peripheral side end surface of the disk substrate 4 by the resistance mold release part 15, the stripping from the stamper 7 can be done with the plane property maintained. After that, when the disk substrate 4 is stripped from the mold 2, by showing "a mold release property" to the peripheral side end surface of the disk substrate 4 by the resistance mold release part 15, even when the molding cycle is short, the stripping of the disk substrate can be done with the plane property maintained. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a disk substrate formed by molding a synthetic resin material to form an optical disk or the like that serves as an information signal recording medium, a substrate molding die apparatus for molding the substrate, and a substrate molding manufacturing method.

  In general, a disk substrate formed by molding a synthetic resin material such as polycarbonate resin that constitutes an optical disk is formed by a mold apparatus for injection molding. This mold apparatus for molding a disk substrate includes a fixed mold and a movable mold that form a molding cavity corresponding to the disk substrate. For example, a predetermined music is provided on the disk substrate molding surface side of the fixed mold. A stamper for forming a so-called pit or a pre-groove constituting a recording track on which a desired information signal is recorded, which is a concave / convex pattern corresponding to an information signal such as a signal, is arranged, and the central portion of the protrusion on the movable mold side A punching punch for drilling a centering member engaging hole provided in is provided.

  Molding of a disk substrate using such a mold apparatus is performed by injecting and filling a synthetic resin material melted through an injection port of a sprue bush arranged in a fixed side mold into a molding cavity. Then, after the disk substrate was molded in the molding cavity, the punching punch was moved to form a centering member engagement hole in the center, and a pit or pregroove was molded on one main surface side. A disk substrate is formed.

  With regard to such a substrate molding die device, for example, Patent Document 1 discloses a mold release resistance portion comprising protrusions / holes or ring-like protrusions / grooves arranged at points in the circumferential direction on the movable mold side. Is provided on the portion corresponding to the outer peripheral side wall of the disk substrate or the portion corresponding to the inner wall of the protrusion protruding from the inner central portion.

Japanese Patent No. 0301103

  In the device described in Patent Document 1, easy and reliable release (primary peeling) of a disk substrate formed from a stamper for forming a pregroove constituting a pit or recording track that is an uneven pattern is performed. However, if the molding cycle is shortened, as the next step of releasing from this stamper, protrusions / holes arranged at points in the circumferential direction at the time of releasing from the movable mold (secondary peeling) Alternatively, the mold release resistance due to the ring-shaped protrusions / grooves increases, and the mold cannot be easily released from the movable mold. As a result, it is known that the flatness of the disk deteriorates, and in particular, the mechanical characteristic surface shake, the circumferential tilt, and the radial tilt are deteriorated and cannot be used as a disk substrate of an optical disk. In particular, DVD discs (DVD + R / RW, etc.), which have recently been widely spread and developed, are not suitable for such discs because disc flatness is important in order to be compatible with high-speed recording. It will be a thing.

  That is, according to Patent Document 1, the resistance at the time of peeling the disk substrate from the stamper is provided by the release resistance portion, and the shortening of the molding cycle is not considered, and the disk substrate from the stamper is simply considered. This is merely considering the releasability (primary peeling).

  It is an object of the present invention to ensure the flatness of a disk substrate that is molded and manufactured through a peeling process while achieving a shortening of the molding cycle.

  The invention described in claim 1 is a substrate molding die apparatus for molding a disk substrate using a synthetic resin material, comprising a fixed side mold and a movable side mold constituting a substrate molding cavity, and these molds A resistance release portion by surface roughening was provided on the inner peripheral surface of the mold corresponding to the outer peripheral side end surface of the disk substrate formed on one side of the mold.

  In the present invention and the following invention, the “resistance release part” refers to the case where a disk substrate formed by filling a synthetic resin material into a substrate molding cavity loaded with a transfer stamper is peeled off from the stamper. In addition to exhibiting “resistance” to the outer peripheral end surface of the disk substrate, and subsequently exhibiting “releasability” to the outer peripheral end surface of the disk substrate when the disk substrate is peeled off from the mold. This means the part Therefore, as disclosed in Patent Document 1, when a disk substrate formed by filling a synthetic resin material into a substrate molding cavity loaded with a transfer stamper is peeled from the stamper (at the time of mold release), This is different from a “release resistance part” intended only to show “resistance” with respect to the outer peripheral side end face.

  According to a second aspect of the present invention, in the mold apparatus for molding a substrate according to the first aspect, the resistance release part by surface roughening is a point set, a line set or a composite thereof with respect to the inner peripheral surface of the mold. It is formed by carrying out by planar shape.

According to a third aspect of the present invention, in the substrate molding die apparatus according to the first or second aspect, the resistance release portion is roughened so that a resistance area in the substrate drawing direction is 18 mm ² or more and the number of steps in the substrate drawing direction is rough. However, the roughening depth for one stage is 3 to 90 μm. In this case, more preferably, the one-step roughing depth of the resistance release portion is 3 to 20 μm.

  A fifth aspect of the present invention is the substrate molding die apparatus according to any one of the first to fourth aspects, wherein the resistance release portion is roughened by a surface roughening process on the inner peripheral surface of the die. Has been. In this case, the surface roughening process includes WPC (Wide Peening and Clean) process (Claim 6), blasting process using beads (Claim 7), shot peening process (Claim 8), and micro dimple processing ( (Claim 9), cutting or polishing treatment with a finely roughened bite surface (Claim 10), or treatment using a chemical or solvent for roughening the metal surface (Claim 11).

  A disc substrate according to a twelfth aspect of the present invention is formed of a resistance release portion that is made of a synthetic resin material using the substrate molding die device according to any one of the first to eleventh aspects and is roughened. A rough surface portion is provided on the outer end surface.

  The invention according to claim 13 is a substrate molding manufacturing method for molding a disk substrate using a substrate molding die apparatus comprising a stationary mold and a movable mold that constitute a substrate molding cavity, Using one of the movable side mold or the fixed side mold, a mold formed on the inner peripheral surface of the mold corresponding to the outer peripheral side end surface of the disk substrate on which the resistance release portion due to surface roughening is formed, Filling the substrate molding cavity loaded with a transfer stamper with a synthetic resin material to mold a disk substrate; and removing the disk substrate formed of the synthetic resin material from the stamper; A secondary peeling step of peeling off the disk substrate from the mold.

  According to a fourteenth aspect of the present invention, in the substrate molding manufacturing method according to the thirteenth aspect, the resistance due to surface roughening is obtained by performing roughening on the inner peripheral surface of the mold in a planar shape by a point set, a line set or a combination thereof. A mold having a release part was used.

According to a fifteenth aspect of the present invention, in the substrate molding manufacturing method according to the thirteenth or fourteenth aspect, the resistance area in the substrate drawing direction is 18 mm ² or more, the number of roughing steps in the drawing direction of the substrate is two or more, and the roughing depth for one step. A mold having the resistance release portion formed by surface roughening with a thickness of 3 to 90 μm was used. In this case, it is preferable to use a mold in which the resistance release portion is formed by surface roughening, in which the roughness depth for one step is 3 to 20 μm.

  According to the present invention, since the resistance release portion by surface roughening is provided on the inner peripheral surface of the mold corresponding to the outer peripheral side end surface of the disk substrate, the substrate loaded with the transfer stamper in the substrate molding manufacturing process When the disk substrate formed by filling the molding cavity with the synthetic resin material is peeled off from the stamper, the resistance release part exhibits “resistance” with respect to the outer peripheral side end surface of the disk substrate. When the disk substrate is peeled off from the mold, the resistance release part is “releasing to the outer peripheral side end surface of the disk substrate. ", The disc substrate can be peeled off while maintaining the flatness even if the molding cycle is short. Therefore, the disc can be produced while ensuring the disc flatness required for a high-speed compatible DVD disc even under a short molding cycle.

In particular, the resistance release part due to surface roughening is formed by performing surface roughening with respect to the inner peripheral surface of the mold by a point set, a line set or a composite thereof, and the resistance release part is roughened. By setting the resistance area in the substrate drawing direction to 18 mm ² or more, the number of roughing steps in the substrate drawing direction to 2 steps or more, and the roughing depth for one step to 3 to 90 μm, the above “resistance” and “release property” Can be surely exhibited. That is, if the roughing depth for one step is less than 3 μm, the rough mountain is too fine and the strength of the mountain is weak and easily crushed, so sufficient resistance cannot be obtained when peeling from the stamper, but it is 3 μm or more. , "Resistance" can be ensured, and if the roughening depth for one step is greater than 90 μm, the amount of catch (resistance) when the disk substrate is peeled off from the mold becomes too large under a short molding cycle. However, since it is 90 μm or less, even when the molding cycle is shortened, the “release property” can be ensured.

  Further, such a resistance release portion due to surface roughening can be formed by various surface roughening treatments. It is possible to easily create a rough surface that is uniform without roughening and can reliably exhibit the above-described “resistance” and “releasing properties”.

  The best mode for carrying out the present invention will be described with reference to the drawings. This embodiment shows an example of application to a disk substrate molding die apparatus for an optical disk such as a DVD-based disk such as DVD + R and a substrate molding manufacturing method using the apparatus.

  1A and 1B show a mold structure and the like of the disk substrate molding die device, wherein FIG. 1A is a schematic side view in a mold open state, and FIG. 1B is a schematic side view in a mold clamped state. First, a basic schematic configuration of a disk substrate molding die device and a basic substrate molding manufacturing method will be described with reference to FIG.

  As shown in FIG. 1, the disk substrate molding die apparatus is movable and supported by a fixed-side mold 1 and a fixed-side mold 1 through a hydraulic mechanism or the like so as to be able to advance and retreat in a direction of approaching and separating. A mold 3 including a side mold 2 is provided. A substrate molding cavity 5 corresponding to the disk substrate 4 to be molded is defined between the fixed mold 1 and the movable mold 2 constituting the mold 3. A synthetic resin material such as a molten polycarbonate resin supplied from an injection molding machine (not shown) is located in the center of the substrate molding cavity 5 on the fixed mold 1 side. A sprue bush 6 is provided to flow into the pipe. A resin injection nozzle 6a is formed at the center of the sprue bush 6, and the molten synthetic resin material supplied from the injection molding machine is injected into the substrate molding cavity 5 through the resin injection nozzle 6a. The

  Further, a holder support (not shown) on which an inner peripheral side stamper presser (not shown) for supporting an inner peripheral side of a stamper 7 described later is fitted is fitted on the outer peripheral side of the sprue bush 6. It is arranged. On the molding surface side that defines the substrate molding cavity 5 of the fixed mold 1, a so-called pit that is a minute uneven pattern corresponding to an information signal recorded on the optical disk, or a signal recording portion of the optical disk is formed. A stamper 7 for forming a pre-groove constituting a recording track is mounted. The stamper 7 is supported by an inner peripheral stamper presser fitted around the holder support at the periphery of the center hole, and the outer peripheral side is sucked and attached by air suction from a suction port (not shown). .

  On the other hand, the other main part of the disk substrate 4 cooperates with the projection forming part provided on the fixed side mold 1 in the central part on the molding surface side that defines the substrate molding cavity 5 of the movable side mold 2. A protrusion forming recess 9 for forming the protrusion 8 protruding on the surface side is formed. A punching punch 10 of a punching cut punch mechanism for punching and forming a centering member engaging hole formed as a through hole at the center of the protrusion 8 is disposed at the center of the protrusion forming recess 9. This punching punch 10 is disposed in the movable mold 2 so as to advance and retreat in the sleeve 11. The sleeve 11 is supported so as to be movable back and forth with respect to the movable mold 2, and pushes the molded disk substrate 4 out of the movable mold 2.

  The outer periphery of the movable mold 2 is divided into the outer periphery of the substrate molding cavity 4, and the outer peripheral surface of the disk substrate 4 to be molded is molded as an outer peripheral surface (outer peripheral single surface). A molding member cavity ring 12 is provided. The cavity 12 has a smooth abutting surface on the front end surface side, and is arranged so as to touch an outer peripheral portion of a stamper attached to the fixed side mold 1. When the movable side mold 2 moves to the fixed side mold 1 and is brought into a mold-clamped state as shown in FIG. 1B, the cavity 12 contacts the stamper 7 with a smooth abutting surface. Then, the substrate forming cavity 5 is sealed.

  Further, the molding surface of the movable mold 2 is on the light beam incident surface side of the disk substrate 4 so that the other main surface of the disk substrate 4 which is a smooth surface with high accuracy can be molded. The mirror surface 13 is a smooth surface with high accuracy.

  Then, after the disk substrate 4 is molded, when performing mold opening (primary peeling) in which the movable mold 2 is moved away from the fixed mold 1, the disk substrate 4 is moved to the movable mold 2 side. And then ejecting the ejector 14 in the movable mold 2 to release the disk substrate 4 from the movable mold 2 (secondary peeling).

  In such a basic configuration, in order to mold the disk substrate 4, a mold-clamping state in which the movable mold 2 is brought close to the fixed mold 1 side is set (see FIG. 1B). In this clamping state, a synthetic resin material such as a molten polycarbonate resin supplied from an injection molding machine is injected and filled into the substrate molding cavity 5 through the resin injection port 6a of the sprue bush 6. At this time, the punching punch 10 is moved to form a centering member engagement hole at the center of the protrusion. Next, the movable mold 2 is moved to the fixed mold 1 side, the synthetic resin material filled in the substrate molding cavity 5 is clamped and cooled, and the substrate molding cavity 5 is cooled. The disk substrate 4 corresponding to the above is formed. This is performed as a resin filling & substrate molding process.

  After the disk substrate 4 is formed, the disk substrate 4 is peeled off from the stamper 7 by performing mold opening (primary peeling) in which the movable mold 2 is moved away from the fixed mold 1 ( Primary peeling step). At this time, the disk substrate 4 is held on the movable mold 2 side. Subsequently, the ejector 14 in the movable mold 2 is protruded to release (secondarily peel) the disk substrate 4 from the movable mold 2 (secondary peeling step).

With respect to such a disk substrate molding die apparatus and a substrate molding manufacturing method using the apparatus, in the present embodiment, a part of the mold 3 is formed and the outer peripheral side peripheral surface (end surface) of the disk substrate 4 is supported. It is characterized in that a resistance release portion 15 by surface roughening is provided on the inner peripheral surface (mold inner peripheral surface) of the cavity ring 12 to be performed. The resistance release part 15 by such surface roughening is formed by performing surface roughening on the inner peripheral surface of the cavity ring 12 by a point set, a line set, or a combination thereof, and the roughening is performed. As for the degree of resistance, the resistance area in the substrate drawing direction is 18 mm ² or more, the number of roughening steps in the substrate drawing direction is two steps or more, and the roughing depth for one step is 3 to 90 μm (details will be described later). . Here, the resistance release part 15 is used when the disk substrate 4 formed by filling the synthetic resin material into the substrate molding cavity 5 loaded with the transfer stamper 7 is peeled off from the stamper 7. 4 shows “resistance” with respect to the outer peripheral side end face, and after that, shows “release” with respect to the outer peripheral side end face of the disc substrate 4 when the disc substrate 4 is peeled off from the movable die 2. It means the part which gave the characteristic. “Roughening is performed in a planar shape by a point set, a line set, or a combination thereof” is a point set in which minute uneven portions are scattered in a point shape over the entire inner peripheral surface of the cavity 12, or In order to obtain a line set in which minute ridges are scattered or intersected in a linear manner in the entire inner peripheral surface of the cavity ring 12, or a composite result obtained by appropriately combining these, This means that the inner peripheral surface is roughened two-dimensionally.

  Thus, by providing the resistance release portion 15 by roughening on the inner peripheral surface of the cavity ring 12, the outer peripheral side end surface corresponds to the roughening of the resistance release portion 15 in the molding process of the disk substrate 4. As a result, the roughened portion 4a is formed. Then, when the disk substrate 4 formed by opening the mold is peeled off from the stamper 7 side, the resistance release portion 15 exhibits resistance to the roughened portion 4 a on the outer peripheral side end surface of the disk substrate 4. Since the disk substrate 4 is maintained in an integrated state with the movable mold 2, the disk substrate 4 is kept flat from the surface of the stamper 7 without being shaken, deteriorating the circumferential tilt and the radial tilt. The mold can be surely released (primary separation) and moved to the movable mold 2 side where the stamper 7 is not disposed.

  Next, when the disk substrate 4 is peeled off from the movable side mold 2 (secondary peeling), the resistance release part 15 due to surface roughening is formed on the disk without taking sufficient time for the disk substrate 4 to shrink. The surface roughness portion 4a on the outer peripheral side end surface of the substrate 4 exhibits releasability, and even if the molding cycle is shortened (during high-speed molding), the outer peripheral side end surface of the disk substrate 4 is caught by the cab ring 12. It is possible to peel off while maintaining flatness.

  Note that a roughened surface 4a is formed on the outer peripheral side end surface of the disk substrate 4 corresponding to the resistance release portion 15, but the roughened portion 4a is not formed with a signal recording portion. Since it is an outer peripheral side end surface, the influence with respect to the board | substrate body in which a signal recording part is formed can be suppressed.

  In the present embodiment, the side on which the stamper 7 is mounted is the fixed die 1 and the side on which the punching punch 10 is disposed is the movable die 2. However, this relationship is reversed. It may be what you did.

  By the way, the degree of surface roughening of the above-mentioned resistance release part 15, the formation method, etc. will be considered including the comparison with the conventional method.

  First, samples (1), (2), and (3) serving as comparative examples according to Patent Document 1 were produced, and samples (4) and (5) were produced as examples according to the present embodiment. Table 1 shows numerical examples of these samples.

Sample (1) has a 0.2 mm square recess on the inner peripheral surface of the cavity, and a 24-step portion of the cavity is formed uniformly over one round, and one round portion is formed. The length (a) is 4.8 mm, the amount of catch (depth b for one step) is 0.2 mm, and the resistance area is 0.96 mm ² . Sample (2) is formed by forming a corner ring (square ring; see FIG. 2 (A)) with a width of 0.1 mm on the inner peripheral surface of the cavity ring for one step over the entire circumference as a release resistance portion. The length (a) for one turn is 37699 mm, the amount of catch (depth b for one step) is 0.1 mm, and the resistance area is 37.70 mm ² . Sample (3) is formed by forming a corner ring (square ring; see FIG. 2 (B)) having a width of 0.05 mm on the inner peripheral surface of the cab ring for one step over the entire circumference as a release resistance portion. The length (a) for one turn is 37699 mm, the amount of catch (depth b for one step) is 0.05 mm, and the resistance area is 18.85 mm ² . On the other hand, in the sample (4), a resistance release portion 15 having a surface roughness of 0.020 mm is formed in a planar shape on the inner peripheral surface of the cavity ring 12 (see FIG. 2C). ), The length (a) for one round is 37699 mm, the amount of catch (depth b for one step) is 0.02 mm, the number of steps in the disk pulling direction is 12, and the resistance area is 45.24 mm ² . . On the other hand, in the sample (5), the resistance release part 15 having a surface roughness of 0.012 mm is formed on the inner peripheral surface of the cavity 12 in a planar shape over one turn, and the length of one turn is (a) is 376.99Mm, caught the amount (depth b of one step) is 0.012 mm, number 13 stage disk drawing direction, the resistance area is 29.41mm ^2. In addition, since the rough surface portion of the resistance release portion 15 in the samples (4) and (5) can be considered as a triangular cross section, the resistance area d = (a * b) / 2 * c was obtained.

  The surface roughness of these samples was measured using a Form Taly-Surf S6 (Taylor Hobson) surface roughness measuring machine. 3A and 3B show examples of actual roughness data measured by these surface roughness measuring machines. Figures (a) and (b) show examples of the surface roughness of the same part, whereas Fig. 3 (a) shows the results measured with a 3 mm stroke, whereas Figure 3 (b) shows the results. In order to make the roughness shape easier to see by chart display, the result of remeasurement with a 1 mm stroke is shown. The example shown in FIG. 3 shows an example when the surface roughness of the sample (5) is 0.012 mm. Further, the number of stages of Samples (4) and (5) shown in Table 1 indicates the result of reading how many stages are present with respect to the disk substrate plate thickness of 0.6 mm from the actual roughness chart.

Based on these sample examples, the relationship with the molding cycle time and the results of the mechanical property evaluation will be described. As for mechanical evaluation, as shown in FIG. 2, the molding cycle time, outer peripheral axial acceleration, outer peripheral radial tilt, and outer peripheral tilt are measured. Based on these results, whether the mechanical property evaluation is OK or NG. Is evaluated. The “peripheral radial tilt” is an angular representation of the radial curvature of the disk substrate, and this value deteriorates and affects the offset and amplitude of the push-pull signal on a substrate that shows a large value. Smaller is better. The “peripheral circumferential direction tilt” is an angular representation of the warpage of the disk substrate in the circumferential direction. Similarly, the smaller the numerical value, the better. The “peripheral axis direction acceleration” means the acceleration of the recording layer in the direction perpendicular to the reference surface when the rotational speed is 16 Hz (960 rpm, CAV method), and this acceleration is deteriorated due to irregularities on the disk surface. In the case of a substrate showing a large value, the focus / tracking servo pull-in responsiveness, followability, and stability are affected. In recent years, the quality of this axial acceleration has been regarded as important for DVD-based discs that have been recorded at high speed. This axial acceleration is defined by the residual focus / tracking error according to the DVD + R / RW Orange Book, for example. Accordingly, 2.1 m / s ² or less is demanded in terms of axial acceleration. Also in the present embodiment, the mechanical characteristic evaluation is OK when the axial acceleration is 2.1 m / s ² or less. Regarding the molding cycle time, in the present embodiment, the target value is 5.5 s or less. These mechanical properties were measured using a measuring machine called Biref-126P (Dr. Schenk).

First, when the mold opening speed is constant, the boundary of whether or not the primary peeling is performed when the disk substrate is peeled off from the stamper is 18 mm ² as the resistance area in the substrate drawing direction, and this resistance area is 18 mm ^2. If it is smaller than that, it has been found that peeling between the stamper disk substrate cannot be performed well. Therefore, in the case of sample (1), the disk substrate could not be successfully produced at this stage regardless of the molding cycle time.

Next, for sample (2), if the molding cycle time is 9.6 s as shown in FIG. 2, the axial acceleration is 1.4 m / s ² , and for sample (3) As shown in FIG. 2, when the molding cycle time is 8.4 s, the axial acceleration is 1.6 m / s ² whereas the molding cycle time is shortened to 6.7 s. In this example, the axial acceleration was 4.7 m / s ² and the bending of the disk radius R = 50 mm to R = 57 mm caused the disk mirror surface direction (−tilt) to become NG. is there. On the other hand, as shown in FIG. 2, for sample (5), even when the molding cycle time is shortened to the target value of 5.5 s, the axial acceleration is 1.7 m / s ² and the tilt is small. All evaluations were OK. Therefore, regarding the surface roughness, a plurality of steps are required in the substrate drawing direction, and when viewed at a depth (b) of one step, about 0.09 mm is a boundary whether or not the molding cycle time 9 s can be achieved. 0.05 mm is a boundary whether or not the molding cycle time 7 s can be achieved, and about 0.02 mm is considered a boundary whether or not the molding cycle time 5.5 s can be achieved (see FIG. 4). .

  In other words, as in samples (4) and (5), the resistance area in the substrate drawing direction is increased by fine surface roughening, that is, the amount of resistance is increased while the depth of one step is reduced. And better mechanical properties. It is better that the amount of resistance (resistance area) in the direction of drawing out the substrate is larger than the primary peeling from the stamper surface. The rough one-step depth is shallower when the disk substrate 4 is removed from the mold 3, and when the time required for cooling and shrinkage of the disk substrate 4 is shortened especially when the molding cycle time is shortened. It can be pulled out without being caught. In the case of sample (3), the molding cycle time is 6.7 s in the release resistor portion of the method of Patent Document 1 formed in a ring shape in one step in the substrate drawing direction as in samples (2) and (3) shown in Table 1. Thus, deterioration in the outer peripheral radial direction has already occurred due to catching at the time of secondary peeling. Since the disk outer peripheral end surface was pulled out, the disk substrate was bent in the disk mirror surface direction (-tilt) from the radius R = 50 mm to R = 57 mm. On the other hand, as shown in sample (5), the amount of resistance in the substrate drawing direction is increased by fine surface roughening, and the depth of one step is reduced to a shallow depth. Good mechanical properties have been obtained even below.

  Considering the depth of one step of this roughening, the function required for the resistance release part 15 is achieved by setting the depth of one step of 3-90 μm, more preferably 3-20 μm. It was something that could be demonstrated reliably. Sample (5) shows a case where the roughening depth is 12 μm as an optimal example. That is, if the roughing depth for one step is smaller than 3 μm, the rough mountain is too thin and the strength of the mountain is weak and easily crushed. Therefore, sufficient resistance cannot be obtained when peeling from the stamper 7, but it is 3 μm or more. Therefore, “resistance” can be ensured. Also, if the roughening depth of the step is larger than 90 μm, the amount of catch (resistance) when peeling the disk substrate from the mold becomes too large under the condition that the molding cycle is short, but the molding cycle is 90 μm or less. Even when the length is shortened, the “releasability” can be ensured.

FIG. 5 is an explanatory view showing the effect of secondary peeling by such roughening as a graph of the relationship between the roughening depth of one step and the molding cycle. The horizontal axis shows the molding cycle T, and the vertical axis shows the roughening depth for one stage. In this example, the substrate contracts by 90 μm when the molding cycle is 9 s, the substrate contracts by 50 μm when 7 s, and the substrate contracts by 20 μm when 6 s. As a premise, if a resistance area of 18 mm ² or more and ^two or more steps of roughening in the drawing direction of the substrate are secured, if the roughening depth for one step is reduced, the time required for shrinking the substrate cannot be obtained. It can be seen that good secondary peeling without catching is performed even under the molding cycle T condition. In other words, the region A + B + C is a range suitable for use, but when the molding cycle T is shortened, the region A + B is a roughening depth region for one step that can be handled even when the molding cycle T = 5.5 s or less. The 3 to 20 μm region is good. Furthermore, a 12 to 20 μm region, which is a region A portion in which a resistance area of 18 mm ² or more important for primary peeling is sufficiently secured, is favorable.

By the way, the resistance release part 15 by surface roughening as in the samples (4) and (5) can be formed by various surface roughening treatments. In this embodiment, as an example, WPC (Wide Peening) is used. and Clean) processing is used. In the present embodiment, in order to obtain particularly ideal surface roughness, surface roughening is performed by two-step process processing using shot materials having different roughness and shape. For example, as for the shot material, aluminum oxide having an angular shape with an average particle size of 300 μm was used in the first step, and spherical ceramic beads having an average particle size of 45 μm were used in the second step. The shot pressure was 4.0 kgf / cm ^{2 in} both the first step and the second step. The nozzle ejection distance (distance to the object to be processed) was 7 cm. Further, the treatment time was rotated twice so as to hit each part for 30 seconds (the roughness of the treatment was sufficient by one revolution, but the roughness was stabilized by making two revolutions). According to such WPC processing, uniform surface roughness can be easily made without surface roughness. When an angular shot material is used, the shape shown in FIG. 6A is obtained in the WPC process. FIG. 6 shows a horizontal sectional view of the cavity ring 12 as viewed from above as indicated by an arrow A in FIG. 7, but the same applies to the case where the cavity ring 12 is viewed as a BB section in FIG.

  The surface roughening process for forming the resistance release portion 15 by surface roughening on the inner peripheral surface of the cavity 12 is not limited to the WPC process, and for example, a blast process using beads, a shot peening process, a micro dimple A processing treatment, a cutting or polishing treatment with a finely roughened bite surface, a treatment using a chemical / solution for roughening a metal surface, and the like can be appropriately used.

In a processing method in which a shot material, such as WPC treatment, shot peening, microdimple, and blasting with beads, is struck by accelerating the metal surface to perform point set roughening, if the shot material has an angular shape, FIG. If it is round, it has a surface shape as shown in FIG. 6 (b), but any shape can be used if its resistance area is 18 mm ² or more. For example, if it has a simple triangular cross-sectional shape as shown in FIG. 6 (a), the calculation is simply performed with (average roughening depth * length of one circumference) / 2 * (number of steps in the disk drawing direction). And the resistance area can be determined.

Further, FIG. 8 illustrates an example of the surface shape when one round is cut or polished into the same shape. Each surface finish is equal to the surface shape of the tool to be applied while rotating the cabling 12, but the resistance area is calculated by the average roughening depth * length of one round * number of steps in the disk pulling direction and at least 18 mm ² Any surface shape can be used. However, a shape that does not come out even when the disc contracts as shown in FIG. 8D cannot be used.

  Similarly, in the treatment method using a chemical / solution that roughens the metal surface, the resistance area per unit is calculated, and the availability is calculated by calculating the * 1 circumference * the number of steps in the drawing direction. good.

1 shows a mold structure and the like of a disk substrate molding die device according to an embodiment of the present invention, wherein (a) is a schematic side view in a mold open state, and (b) is a schematic side view in a mold clamped state. It is explanatory drawing which shows the shape and mechanical characteristic value of a cavity inner peripheral surface in contrast with the conventional system. It is a characteristic view which shows the example of the measured surface roughness. It is explanatory drawing which shows typically the relationship between a rough shape and shaping | molding cycle time. It is explanatory drawing which summarizes the secondary peeling effect according to the relationship between a rough shape and shaping | molding cycle time, and shows it with a graph. It is a horizontal sectional view of an arrow A direction showing an example of a rough surface shape. It is a perspective view of the cabling for showing a direction of illustration. It is sectional drawing by the BB line which shows the example of a rough surface shape.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fixed side metal mold | die 2 Movable side metal mold | die 4 Disc board | substrate 4a Roughening part 5 Substrate shaping | molding cavity 7 Stamper 12 Part of metal mold | die 15 Resistance mold release part

Claims (16)

In a substrate molding die apparatus that molds a disk substrate using a synthetic resin material,
A fixed side mold and a movable side mold that constitute a substrate molding cavity are provided.
A substrate molding die apparatus, wherein a resistance release portion by surface roughening is provided on an inner peripheral surface of a die corresponding to an outer peripheral side end surface of the disk substrate formed on one of these dies.   2. The resistance release part by surface roughening is formed by performing surface roughening with respect to the inner peripheral surface of the mold by a point set, a line set or a composite thereof. Molding equipment for substrate molding. The roughness of the resistance release part is such that the resistance area in the substrate drawing direction is 18 mm ² or more, the number of roughing steps in the substrate drawing direction is two or more, and the roughing depth for one step is 3 to 90 μm. The mold apparatus for substrate molding according to claim 1 or 2.   4. The substrate molding die apparatus according to claim 3, wherein a roughening depth for one step in the roughening of the resistance release part is 3 to 20 [mu] m.   5. The substrate molding die apparatus according to claim 1, wherein the resistance release portion is roughened by a surface roughening process on the inner peripheral surface of the die.   6. The substrate molding die apparatus according to claim 5, wherein the surface roughening process is a WPC (Wide Peening and Clean) process.   6. The mold apparatus for forming a substrate according to claim 5, wherein the surface roughening process is a blast process using beads.   6. The substrate molding die apparatus according to claim 5, wherein the surface roughening process is a shot peening process.   6. The mold apparatus for forming a substrate according to claim 5, wherein the surface roughening process is a micro dimple process.   6. The substrate molding die apparatus according to claim 5, wherein the surface roughening treatment is a cutting or polishing treatment with a finely roughened bite surface.   6. The substrate molding die apparatus according to claim 5, wherein the surface roughening treatment is a treatment using a chemical or a solvent for roughening a metal surface.   A surface roughened portion formed by a resistance release portion that is made of a synthetic resin material using the substrate molding die device according to any one of claims 1 to 11 and is roughened is provided on an outer peripheral side end surface. Disc substrate. A substrate molding manufacturing method for molding a disk substrate using a substrate molding die apparatus comprising a fixed mold and a movable mold that constitute a substrate molding cavity,
A mold formed on an inner peripheral surface of a mold corresponding to an outer peripheral side end surface of the disk substrate on which a resistance release portion due to surface roughening is formed is used on one of the movable side mold and the fixed side mold. Filling the substrate molding cavity loaded with a transfer stamper with a synthetic resin material and molding a disk substrate;
A primary peeling step of peeling off a disk substrate formed of a synthetic resin material from the stamper;
A secondary peeling step of peeling the disk substrate from the mold;
A substrate molding and manufacturing method comprising:   It is characterized by using a die in which the resistance release part by surface roughening is formed by performing roughening with respect to the inner peripheral surface of the die in a surface shape by a point set, a line set or a combination thereof. The substrate molding manufacturing method according to claim 13. The resistance release part is formed by surface roughening in which the resistance area in the substrate drawing direction is 18 mm ² or more, the number of roughing steps in the substrate drawing direction is two steps or more, and the roughing depth for one step is 3 to 90 μm. 15. The substrate molding manufacturing method according to claim 13, wherein a mold is used. 16. The substrate molding manufacturing method according to claim 15, wherein a mold having the resistance release portion formed by surface roughening with a one-step roughening depth of 3 to 20 [mu] m is used. .

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