JP2013134793A - Method and apparatus for manufacturing glass substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the occurrence of a defect such as a surface flaw, a chipping, a scratch or a surface crack defect in manufacture of a glass substrate.SOLUTION: A suction plate 59 at a tip of a first arm 58 sucks a doughnut-like glass substrate 4 at the top layer of a doughnut-like glass block 3. When a pressure sensor 61 detects the suction by the suction plate 59, the first arm 58 is pulled up and the glass substrate 4 is separated from the glass block 3. The glass substrate 4 is moved to a disk holder 54 by a cylinder 56, and when a position sensor 60 detects that the glass substrate 4 reaches a prescribed position, a pump 57 releases the suction and the glass substrate 4 is stored in the disk holder 54. A bonding agent F at the top layer of the glass block 3 is peeled off from a glass substrate 4 in a layer below it by sweeping its surface while pressing it by a roller 62a at a tip of a second arm 62. The bonding agent F which has been peeled off is led to a prescribed recovery position by a water flow in a water tank 51.

Description

  The present invention relates to a glass substrate manufacturing method and a glass substrate manufacturing apparatus used for a magnetic disk device such as a hard disk device.

  In recent years, information terminals such as personal computers, car navigation systems, mobile phones, and portable music players have been equipped with large-capacity hard disk devices, and this type of large-capacity hard disk device has a magnetic disk capable of high-density recording. Used. As a glass substrate capable of high-density recording, a glass substrate having excellent surface smoothness and high rigidity is used.

  As a conventional method for producing a glass substrate for a magnetic disk, the method described in Patent Document 1 is known. In this method, as a starting glass base material, a glass base material several times thicker than the thickness of the finished product is formed by a method such as press molding or sheet glass molding. Next, a first lapping process for lapping the main surface of the glass base material, an inner / outer diameter coring process for forming a donut-shaped glass substrate by coring, grinding of end faces on the inner and outer circumferences, and chamfering of edge portions The inner and outer peripheral chamfering step for performing the inner and outer peripheral end surface polishing steps for polishing the inner and outer peripheral end surfaces are sequentially executed. Thereafter, in the second lapping step, the thickness is adjusted to about the thickness of the finished product, and a considerable amount of the surface of the glass substrate is ground for chipping removal. Subsequently, the polishing process is performed a plurality of times to finish the surface of the glass substrate in a mirror state.

  Patent Document 2 discloses that a starting glass base material is heated and stretched to produce a thin glass plate, and a plurality of the produced thin glass plates are overlapped and integrated via a spacer, and the coring and inner and outer circumferences are integrated. A method of performing end surface grinding to form a donut-shaped glass substrate is disclosed.

  By the way, when the inner and outer peripheral end surfaces are ground in a state where a plurality of glass plates are overlapped and processing such as chamfering is performed in the next step, it is necessary to separate the glass substrate from the spacer.

  Then, the method of isolate | separating a glass substrate and a spacer is examined, and the isolation | separation method as described in patent document 3, 4, 5 is proposed. In the separation methods described in these Patent Documents 3 to 5, the spacer is peeled from the glass substrate by applying a high-pressure water stream to the spacer.

JP 2005-225713 A JP 2008-198110 A JP 2008-302448 A JP 2008-307612 A JP 2009-48688 A JP 2009-48735 A JP 2011-48888 A

  However, when the spacer and the glass substrate are firmly adhered, it is difficult to peel the spacer from the glass substrate even when a high-pressure water stream described in Patent Documents 3 to 5 is used.

  Further, even when the water pressure of this water flow was further increased to separate the spacers, the plurality of spacers were only partially peeled off. In this case, the glass substrates with standing edges come into contact with each other, and surface flaws occur or chipping occurs at the edge portions. Therefore, in the conventional separation method, it is difficult to separate the glass substrates one by one and store them in the storage cassette without causing defects such as surface scratches.

  In order to avoid the above-described problem, a method of manually separating the glass substrate and the spacer can be considered. However, this method not only requires time and cost, but also has a new problem of causing surface scratches and chipping on the glass substrate due to handling mistakes and the like.

  The present invention has been made in view of the above, and in the production of a glass substrate, a method for producing a glass substrate capable of suppressing the occurrence of defects such as surface scratches, chipping, scratches, or surface crack defects, and It aims at providing the manufacturing apparatus of a glass substrate.

  In order to solve the above-described problems and achieve the above object, a method for manufacturing a glass substrate according to the present invention is a predetermined method for forming a predetermined-shaped glass block in which a plurality of predetermined-shaped glass substrates are laminated with a spacer interposed therebetween. A glass substrate forming step, a glass substrate separating step of separating the outermost glass substrate from a predetermined shape glass block in a state where at least an interface portion between the glass substrate and the spacer is immersed in a liquid, and at least a spacer and a glass substrate With the interface portion immersed in a liquid, the sweeping means is swept from one end of the spacer toward the other end while applying a predetermined pressure to the spacer on the outermost layer of the glass block of the predetermined shape, thereby And a spacer peeling step of peeling the surface layer spacer from the glass block.

  The method for producing a glass substrate according to the present invention includes, in the above invention, a slide contact step of sliding the separation surface separated from the glass block having a predetermined shape in the glass substrate to the slide contact means after the glass substrate separation step. Features.

The glass substrate manufacturing method according to the present invention is characterized in that, in the above invention, the predetermined pressure is 0.4 gf / mm ² or more and 40 gf / mm ² or less.

The method for producing a glass substrate according to the present invention is characterized in that, in the above invention, the elastic modulus of the spacer in the separation step is 1.00 × 10 ⁵ MPa to 1.00 × 10 ¹⁰ MPa.

  The method for producing a glass substrate according to the present invention is characterized in that, in the above invention, the liquid is water or water containing 1% by weight or more of a surfactant.

  The glass substrate manufacturing method according to the present invention is characterized in that, in the above invention, the sweep means comprises an arm having a roller made of hard rubber attached to the tip.

  In the glass substrate manufacturing method according to the present invention, in the above invention, the predetermined-shaped glass block forming step includes a step of forming a glass block obtained by laminating a plurality of thin glass plates through a spacer, and a predetermined shape of the glass block. And a step of cutting.

  An apparatus for manufacturing a glass substrate according to the present invention is an apparatus for manufacturing a glass substrate configured such that a glass substrate can be separated into a single wafer from a glass block having a predetermined shape in which a plurality of glass substrates having a predetermined shape are laminated with a spacer interposed therebetween. A liquid storage means for storing liquid in a state where at least an interface portion between the glass substrate and the spacer can be immersed, and a glass substrate separation means configured to be able to separate the outermost glass substrate from the predetermined shape glass block; It is configured to allow sweeping from one end of the spacer to the other end while applying a predetermined pressure to the spacer on the outermost layer of the predetermined shape glass block on the predetermined shape glass block from which the outermost glass substrate is separated And sweeping means.

  The glass substrate manufacturing apparatus according to the present invention is characterized in that, in the invention described above, the glass substrate manufacturing apparatus further includes a sliding contact means configured to be capable of sliding contact with the separation surface on the side separated from the spacer in the glass substrate by the glass substrate separating means. And

  The glass substrate manufacturing apparatus according to the present invention is characterized in that, in the above-mentioned invention, the sweeping means has an arm having a roller made of hard rubber attached to the tip.

  According to the method for manufacturing a glass substrate and the apparatus for manufacturing a glass substrate according to the present invention, generation of defects such as surface scratches, chipping, scratches, and surface crack defects can be suppressed in manufacturing the glass substrate.

FIG. 1 is a flowchart showing a method for manufacturing a glass substrate according to an embodiment of the present invention. FIG. 2 is a schematic perspective view of a glass block according to an embodiment of the present invention. FIG. 3 is a cross-sectional view illustrating the formation of a donut-shaped glass block according to an embodiment of the present invention. FIG. 4 is a perspective view showing separation of a glass substrate according to an embodiment of the present invention. FIG. 5 is a schematic view showing a glass substrate separating apparatus according to an embodiment of the present invention. FIG. 6 is a schematic view showing a glass substrate separating apparatus according to an embodiment of the present invention. FIG. 7 is a flowchart illustrating a glass substrate separation method according to an embodiment of the present invention.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In all the drawings of the following embodiment, the same or corresponding parts are denoted by the same reference numerals. Further, the present invention is not limited to the embodiment described below.

(Glass substrate manufacturing method)
First, the manufacturing method of the glass substrate by one Embodiment of this invention is demonstrated. FIG. 1 shows a flowchart of a glass substrate manufacturing method according to an embodiment of the present invention.

  As shown in FIG. 1, first, in step S101, a thin glass sheet is formed. Specifically, for example, a preform glass plate having a predetermined thickness is formed using a known manufacturing method such as a float method, a fusion method, a downdraw method, a pulling method using molten glass as a raw material. Is heated and stretched to a predetermined thickness using a redraw method to form a thin glass sheet. In addition, you may shape | mold thin glass by the float method, the fusion method, the down draw method, the raising method, etc., without using the redraw method. The thin glass can be cut into a predetermined size as required.

  Next, in step S102, the glass block 1 is formed. In step S102, as shown in FIG. 2, a plurality of the thin glass plates 2 formed in step S101 are stacked and fixed and integrated through a bonding agent F as a spacer to form a glass block 1. As a method of fixing when forming the glass block 1, a bonding agent F made of an ultraviolet curable resin is filled between the thin glass plates 2 and cured and fixed. In particular, in a cleaning process, which is a subsequent process, a type of bonding agent that can easily peel off a plurality of glass substrates that are fixed and integrated using warm water, boiling water, water, or an organic solvent one by one. Is preferably used.

  Next, in step S103, a donut-shaped glass block 3 is formed as a predetermined-shaped glass block. In step S103, as shown in FIG. 3, an apparatus is used in which a double core grindstone 102 in which an inner diameter processing grindstone and an outer diameter processing grindstone are coaxially arranged is attached to the tip of the spindle 101. Then, the double core grindstone 102 is lowered while rotating to the glass block 1 fixed to the fixing base 104 by the fixing means 103 such as suction or clamp, and the coring is applied while applying the grinding liquid to the glass block 1 and the double core grindstone 102. The thin glass 2 and the bonding agent F are ground together to form the outer diameter and the inner diameter at the same time, and the donut-shaped glass block 3 having the circular hole 31 at the center is formed. Thus, by coring the plurality of thin glass plates 2 in the state of the glass block 1 via the bonding agent F, the edge portions of the inner and outer circumferences of each thin glass plate 2 are at least one of the upper side and the lower side. It is formed while being pressed by the thin glass plate 2 fixed thereto with the bonding agent F interposed therebetween.

  Next, in step S104, the inner periphery and outer periphery of the donut-shaped glass block 3 are ground. In step S104, the donut-shaped glass block 3 is first rotated in a state of being fixed by a fixing means such as suction or clamp. Then, the cylindrical or columnar outer peripheral end face grinding grindstone and the inner peripheral end face grinding grindstone attached to the respective tips of the spindle 101 are arranged at predetermined positions and rotated at high speed. At this time, the outer peripheral end face grinding grindstone and the inner peripheral end face grinding grindstone are pressed against the outer peripheral end face and the inner peripheral end face of the doughnut-shaped glass block 3 so as to sandwich the donut-shaped glass block 3, and are raised and lowered by the stage. The block 3 is moved up and down. In this case, a predetermined amount of grinding may be performed to finish the finished product size, or the finished product size may be finished by additional processing with a double core grindstone designed to have the finished product size.

  Next, in step S105, the doughnut-shaped glass substrate 4 is separated from the donut-shaped glass block 3 and stored, and cleaning is performed. As shown in FIG. 4, in the separation and storage process, the doughnut-shaped glass block 3 whose outer peripheral end surface and inner peripheral end surface are ground is bonded to the bonding agent composed of the donut-shaped glass substrate and the ultraviolet curable resin by the separation storage device. Separate F from each other. Thereafter, the doughnut-shaped glass substrate 4 separated into single sheets is stored in a disk holder (not shown in FIG. 4) of a separation and storage device, and is cleaned by a conventionally known method such as ultrasonic cleaning. The individually separated donut-shaped glass substrate 4 has a circular hole 42 formed at the center of the main surface 41, and has an outer peripheral end surface 43, an inner peripheral end surface 44, an outer peripheral edge portion 45, and an inner peripheral edge portion 46. The details of the glass substrate separating and storing apparatus and the separating and storing method using the same according to this embodiment will be described later.

  Next, in step S <b> 106, beveling processing of the outer peripheral edge portion 45 and the inner peripheral edge portion 46 of the donut-shaped glass substrate 4 is performed. When the edge portion is chamfered in step S106, the positional relationship between the chamfering grindstone and the donut glass substrate 4 is first adjusted in advance so that the chamfering angle becomes a desired angle. Thereafter, the grindstone is pressed against each of the outer peripheral edge portion 45 and the inner peripheral edge portion 46 of the doughnut-shaped glass substrate 4 in a state where the respective grindstone grindstones and the donut-shaped glass substrate 4 are rotated, and the beveling is performed.

  Next, after polishing the outer peripheral end face 43 and the inner peripheral end face 44 of the donut-shaped glass substrate 4 in step S107, the main surface 41 of the donut-shaped glass substrate 4 is polished in step S108. In the polishing process of the main surface 41 in step S108, the surface roughness is improved and finally obtained so that the surface roughness finally required in the first polishing process and the second polishing process can be efficiently obtained. In addition, polishing that can efficiently obtain a desired shape is performed. Then, it transfers to step S109 and the donut-shaped glass substrate 4 is wash | cleaned by a conventionally well-known method.

  The completed donut-shaped glass substrate 4 has a circular hole 42 formed at the center of the main surface 41, and has an outer peripheral end surface 43 and an inner peripheral end surface 44, and an outer peripheral beveled portion and an inner peripheral beveled portion are formed for chipping. The removed donut-shaped glass substrate 4 is obtained.

  In addition, after forming a predetermined groove | channel with respect to the main surface 41 of this completed donut-shaped glass substrate 4, various magnetic films are formed by conventionally well-known methods, such as sputtering method and a vacuum evaporation method, for example. Thus, a magnetic disk as a magnetic recording medium in which a magnetic film is provided on the surface of the doughnut-shaped glass substrate 4 is manufactured.

(Separate storage device)
Next, a glass substrate separating and storing apparatus according to an embodiment of the present invention used in the method for manufacturing the donut-shaped glass substrate 4 described above, and a separating and storing method using the same will be described. Here, before demonstrating the isolation | separation storage apparatus by this one Embodiment, this inventor's earnest examination is demonstrated.

  First, the inventor collects and analyzes what is determined to be a defective product by visual inspection in the doughnut-shaped glass substrate 4 manufactured by the conventional manufacturing process, regarding the separation and cleaning process in step S105 described above. went. From this analysis, it was found that scratches and surface cracks may occur on the main surface 41 of the doughnut-shaped glass substrate 4, and defects such as chipping and cracks may occur around the outer peripheral edge portion 45 and the outer peripheral end surface 43. .

  The following reasons can be considered about the cause of these defects. The surface defect of the doughnut-shaped glass substrate 4 is 1 when the doughnut-shaped glass substrate 4 is separated from the donut-shaped glass block 3 one by one and then stored in a disk holder or when a plurality of sheets are stacked in the inner and outer peripheral polishing steps. This occurs when the doughnut-shaped glass substrates 4 come into contact with each other when they are stored one by one in the disc holder. Further, chipping and crack defects generated around the outer peripheral end surface 43 of the donut-shaped glass substrate 4 may cause the outer peripheral end surface 43 to collide with the disc holder when the donut-shaped glass substrate 4 is accommodated in the disc holder, Caused by poor handling.

  That is, when the doughnut-shaped glass substrates 4 are separated from the stacked state and stored one by one in the disk holder, the doughnut-shaped glass substrates 4 collide with each other and slid, thereby causing the main surface 41. There is a problem that scratches and surface crack defects occur. In addition, there is a problem that defects such as cracks occur when the outer peripheral end face 43 of the doughnut-shaped glass substrate 4 collides with the disk holder.

  Therefore, the present inventor has further studied in order to solve these problems, and has come to recall the separation and storage device and the separation and storage method using the same according to the present invention. Hereinafter, a separation and storage device and a separation and storage method according to an embodiment of the present invention will be described. 5 and 6 show a separation storage device according to this embodiment.

  As shown in FIGS. 5 and 6, the separation and storage device 50 according to this embodiment includes a water tank 51, a work fixing jig 52, a water flow generation unit 53, and a disk holder 54 as a storage cassette. Further, the separation storage device 50 includes a linear guide 55, a cylinder 56, a pump 57, a first arm 58, an adsorption plate 59, a position sensor 60, a pressure sensor 61, a second arm 62, a pump 63, and an air cylinder 64. A control unit 70 is provided as control means for controlling these units.

  The water tank 51 is a liquid storage means configured to be able to store a liquid such as water, and is configured to be able to control the temperature of the stored liquid as necessary. The workpiece fixing jig 52 is configured such that the main part is immersed in the liquid in the water tank 51, and an opening indicated by a broken line is formed so that the bonding agent F can be moved almost horizontally in the liquid in the liquid. . Further, the work fixing jig 52 is provided with a sliding contact portion 52a made of, for example, hard rubber as sliding contact means protruding from the liquid surface. The workpiece fixing jig 52 is configured so that the doughnut-shaped glass block 3 can be placed in the water tank 51 in a state where at least the interface between the donut-shaped glass substrate 4 and the bonding agent F is immersed in the liquid.

  The water flow generation unit 53 as the water flow generation means includes a pipe 53a and a pump 53b. The pipe 53a is connected to the water tank 51, and the pump 53b circulates the liquid in the water tank 51 through the pipe 53a, thereby generating a water flow in a predetermined direction in the water tank 51. The disk holder 54 is formed with a plurality of grooves for placing the substrates without contacting each other on the inner side portion, for example, and is configured to store the donut-shaped glass substrates 4 one by one.

  Further, the linear guide 55 is provided over the water tank 51, the workpiece fixing jig 52 and the disk holder 54. The linear guide 55 is provided with a cylinder 56 penetrating as a first cylinder. The cylinder 56 is configured to be able to reciprocate in the horizontal direction along the linear guide 55 under the control of the control unit 70. The upper end of the first arm 58 is connected to the cylinder 56 and is configured to be movable up and down by the cylinder 56. The lower end of the first arm 58 is provided with a suction plate 59 configured to suck at least the donut-shaped glass substrate 4. The controller 70 controls the suction pressure of the suction plate 59 by controlling the pump 57.

  The position sensor 60 always detects the position coordinates of the cylinder 56 and the suction plate 59. The position sensor 60 sequentially supplies the detected position coordinate data (position information data) of the cylinder 56 and the suction plate 59 to the control unit 70. Further, the pressure sensor 61 constantly detects the pressure (adsorption force) when adsorbing the doughnut-shaped glass substrate 4 on the adsorption plate 59 and the pressure when not adsorbing, and the pressure of the adsorption pressure of the detected adsorption plate 59 is detected. Information data is sequentially supplied to the control unit 70. Then, the control unit 70 controls the suction pressure of the suction plate 59 by controlling the pump 57 to cause the suction plate 59 to suck the doughnut-shaped glass substrate 4, and the linear guide 55, the cylinder 56 and the first arm 58. And the donut-shaped glass substrate 4 is configured to be conveyed within a predetermined range.

  The second arm 62 is formed, for example, in a Γ-shape and is provided above the water tank 51, and an air cylinder as a second cylinder driven by a pump 63 whose upper end is controlled by the control unit 70. 64. On the other hand, a roller 62 a made of, for example, hard rubber is provided at the lower end of the second arm 62 so as to be rotatable about an axis parallel to the surface of the donut-shaped glass substrate 4. The lower end of the second arm 62 is configured to be dipped in the liquid stored in the water tank 51. The upper end of the second arm 62 configured as described above can be moved in the horizontal direction by the air cylinder 64, and can be rotated like a pendulum around the one end. Therefore, the second arm 62 is configured to be movable within a predetermined range in the horizontal direction under the control of the control unit 70, and the lower end roller 62a is configured to be vertically movable in an arc shape.

  As described above, the separation storage device 50 according to the embodiment is configured. The plurality of separation storage devices 50 are preferably arranged side by side with respect to the plurality of donut-shaped glass blocks 3 in order to separate the donut-shaped glass substrates 4 in parallel. In this case, the water tank 51, the water flow generation unit 53, and the control unit 70 are used in common for each separation storage device 50.

  Next, a separation and storage method using the separation and storage device 50 according to this embodiment configured as described above will be described. FIG. 7 shows a flowchart of the separating and storing method according to this embodiment.

  As shown in FIG. 5, first, the donut-shaped glass block 3 is stored and placed in a predetermined position of the work fixing jig 52 in a state where water or a liquid obtained by adding a surfactant to water is stored in the water tank 51. (Step ST1 in FIG. 7). Here, the temperature of the liquid in the water tank 51 is preferably Tg−30 ° C. or more and Tg + 30 ° C. or less with respect to the glass transition temperature Tg of the bonding agent F in consideration of the elastic modulus in the bonding agent F that is peeled later.

  Next, the control unit 70 moves the cylinder 56 along the linear guide 55 above the workpiece fixing jig 52, and moves the first arm 58 and the suction plate 59 above the donut-shaped glass block 3 (in FIG. 7). Step ST2). The control unit 70 controls the positions of the cylinder 56, the first arm 58, and the suction plate 59 based on the position information data sequentially supplied from the position sensor 60.

  Next, the first arm 58 is pushed out from the cylinder 56 by the control unit 70, and the suction plate 59 is brought into contact with the donut-shaped glass substrate 4 provided on the uppermost layer which is the outermost layer of the donut-shaped glass block 3. The suction plate 59 that has come into contact with the uppermost doughnut-shaped glass substrate 4 starts suction under the control of the pump 57 by the control unit 70 (step ST3 in FIG. 7). Thereafter, the control unit 70 performs the suction by controlling the pump 57 until the pressure of the suction by the suction plate 59 becomes equal to or lower than a predetermined pressure required to suck the doughnut-shaped glass substrate 4 (step in FIG. 7). ST4).

  Then, when the pressure of the suction by the suction plate 59 is reduced by the control unit 70 and it is detected that the pressure sensor 61 has become equal to or lower than the predetermined pressure (step ST4: Yes in FIG. 7), the control unit 70 sets the cylinder. 56 is driven to pull back the first arm 58. As a result, the first arm 58 lifts the doughnut-shaped glass block 3 and separates the donut-shaped glass substrate 4 adsorbed by the adsorbing plate 59 from the bonding agent F (step ST5 in FIG. 7).

  Thereafter, the first arm 58 is pulled back until the lower surface of the separated doughnut-shaped glass substrate 4 becomes substantially the same height as the upper surface of the sliding contact portion 52a. Then, the control unit 70 horizontally moves the cylinder 56 along the linear guide 55 in the direction of the disk holder 54, thereby rubbing the lower surface of the donut-shaped glass substrate 4 with the upper surface of the sliding contact portion 52a (step ST6 in FIG. 7). ). As a result, even when a part of the bonding agent F remains on the lower surface, which is a separation surface of the doughnut-shaped glass substrate 4 from the bonding agent F, the residue can be removed. Can be suppressed.

  Subsequently, the control unit 70 moves the cylinder 56 along the linear guide 55 to a predetermined position above the disc holder 54. Thereafter, when the control unit 70 drives the pump 57 to increase the suction pressure of the suction plate 59 to about atmospheric pressure, the doughnut-shaped glass substrate 4 is detached from the suction plate 59 and stored in a predetermined position of the disk holder 54. (Step ST7 in FIG. 7).

  As described above, the doughnut-shaped glass substrate 4 is separated from the donut-shaped glass block 3 and stored in the disc holder 54. At this time, since the position sensor 60 drives the first arm 58 while detecting the position of the cylinder 56 by the control unit 70, the donut-shaped glass substrate 4 is moved to a predetermined position of the disc holder 54 with a lean operation. Can carry accurately. As a result, sliding or collision between the doughnut-shaped glass substrates 4 or collision between the donut-shaped glass substrate 4 and the disk holder 54 can be prevented. Therefore, the donut-shaped glass substrate 4 is not subjected to scratches or surface cracks, and the donut-shaped glass substrate 4 is fixed to the disc holder 54 without causing defects such as cracks on the outer peripheral end surface of the donut-shaped glass substrate 4. It can be stored in the position continuously and in a short time.

  Next, as shown in FIG. 6, when the doughnut-shaped glass substrate 4 is unloaded from the work fixing jig 52, the uppermost layer, which is the outermost layer of the donut-shaped glass block 3, is the same as the donut-shaped glass substrate 4. The bonding agent F formed in the diameter is exposed. In this state, the control unit 70 drives the pump 63 to drive the air cylinder 64 to push out the second arm 62 and move it above the workpiece fixing jig 52 (step ST8 in FIG. 7). Then, the roller 62a at the lower end of the second arm 62 moving in a pendulum shape is brought into contact with the end of the upper surface of the bonding agent F opposite to the installation position of the air cylinder 64 (step ST9 in FIG. 7). .

In this state, the weight of the second arm 62 acts on the bonding agent F via the roller 62a, and the roller 62a is fixed in the rotational direction. Here, the force for pressing the bonding agent F by the roller 62a is preferably 0.4 to 40 gf / mm ² (10 to 1000 gf / 25 mm ² ). In this embodiment, for example, 6 gf / mm ² (150 gf / 25 mm) is used. ² ).

  In this state, with the roller 62a in contact with the end of the bonding agent F, the air cylinder 64 is driven by the control unit 70 and the second arm 62 is pulled back (step ST10 in FIG. 7). Thereby, the bonding agent F is elastically deformed by the elastic force of the bonding agent F itself and the frictional force with the roller 62a, and is peeled off from the lower donut-shaped glass substrate 4. The peeled bonding agent F moves substantially horizontally from the workpiece fixing jig 52, passes through the opening, and is released into the water tank 51 (step ST11 in FIG. 7). At this time, the portion in contact with the bonding agent F is, for example, a curved surface portion of the roller 62a made of hard rubber, so that a local load does not act on the surface or the edge portion of the donut glass substrate 4.

  The bonding agent F released into the water tank 51 is pushed away from the upstream to the downstream by the liquid flow generated in the direction perpendicular to the paper surface, for example, generated by the water flow generation unit 53, and the recovered basket ( It is flowed to a predetermined accumulation position such as not shown) and collected (step ST12 in FIG. 7). As described above, the water tank 51 is shared by the plurality of separation and storage devices 50, and the liquid flow generated by the water flow generation unit 53 is also used across the plurality of separation and storage devices 50. It is preferable to install the storage device 50 at the most downstream position of the liquid flow.

  Thereafter, a series of separation of the donut-shaped glass substrate 4 from the above-described donut-shaped glass block 3, sliding contact between the lower surface and the sliding contact portion, storage of the donut-shaped glass substrate 4, and peeling of the uppermost bonding agent F are performed. This process is repeated until the doughnut-shaped glass block 3 no longer exists (step ST13 in FIG. 7).

  The above operation is performed independently in each of the plurality of separation storage devices 50. As a result, a plurality of donut-shaped glass substrates 4 can be separated and accommodated simultaneously, and productivity can be significantly improved.

  Next, the Example based on one Embodiment of this invention mentioned above and the comparative example based on a prior art for a comparison are demonstrated. The present invention is not limited to these examples.

(Examples 1-8 and comparative examples)
First, in order to determine the force that causes the roller 62a provided at the tip of the second arm 62 to act on the bonding agent F, a preliminary experiment was performed in advance. In this preliminary experiment, first, a process of peeling the bonding agent F from the donut-shaped glass substrate 4 was performed while applying a pressing force in a state where the contact area of the roller 62a with the bonding agent F was 25 mm ² . . As a result, it was found that peeling may be difficult when the pressing force exceeds 1000 gf / 25 mm ² . This is considered to be caused by an increase in frictional resistance. On the other hand, when the pressing force is less than 10 gf / 25 mm ² , the roller 62a may slide on the bonding agent F, and it has been found that peeling is difficult in this case as well. From these, the pressing force as a predetermined pressure by the rollers 62a of the distal end of the second arm ^{62, 0.4~40gf / mm 2 (10~1000gf /} 25mm 2 (3.92~3.92 × 10 2 kPa)) is preferred. Therefore, in Examples 1 to 8 below, evaluation was performed by setting the force applied by the tip of the separation arm to 6 gf / mm ² (150 gf / 25 mm ² (58.8 kPa)).

  As shown in Table 1, in Examples 1 to 4, the water temperature in the water tank 51 is 5 ° C., 25 ° C., 65 ° C., and 80 according to the separation and storage method using the separation and storage device 50 according to the embodiment described above. The doughnut-shaped glass substrate 4 and the bonding agent F were separated at a temperature of ° C. In Examples 5 to 7, the amount of surfactant added was 0.5 wt%, 1.0 wt%, and 2.0 wt% while the water temperature in the water tank 51 was fixed at 25 ° C, and the donut-shaped glass substrate 4 and Separation from the bonding agent F was performed. In Example 8, the doughnut-shaped glass substrate 4 and the bonding agent F were separated by setting the water temperature to 65 ° C. and adding the surfactant in an amount of 1 wt%. In Examples 1 to 8, a doughnut-shaped glass substrate 4 for a magnetic disk having a diameter of 65.0 mm (2.5 inches) is 1000 according to each condition according to the method for manufacturing a glass substrate according to the embodiment described above. Each sheet was manufactured and evaluated. On the other hand, in the comparative example, the conventional manual separation method is used to separate the doughnut-shaped glass substrate 4 from the bonding agent F. Except for the separation method, the same manufacturing method as in the example is adopted. Then, 1000 donut-shaped glass substrates were manufactured and evaluated.

  In addition, the evaluation index is the separation failure rate, which is the ratio of the bonding agent made of UV curable resin being stored in the disk holder in a state where it adheres to the doughnut-shaped glass substrate, and defects such as scratches and scratches detected by microscopic observation. These are three evaluation indexes, that is, a surface defect rate that is a ratio and an end surface defect rate that is a ratio of defects such as chipping and chipping that are detected by visual observation by applying light from a halogen light source. Of these evaluation indices, the surface defect rate and the end surface defect rate are particularly important because they greatly affect the quality of the doughnut-shaped glass substrate 4 as a product and are difficult to repair.

  From Table 1, when Examples 1-4 are compared, it turns out that since the bonding agent F made of an ultraviolet curable resin becomes softer as the water temperature becomes higher, the separation failure rate tends to decrease. In Example 1 and Example 2, the separation defect rates are 5.0% and 1.0%, respectively, but the surface defect rate and the end surface defect rate are both 0%. It can be seen that the quality of the final product 4 is not affected.

  Moreover, when Examples 1-8 are compared with Comparative Examples, when the separation method according to Examples 1-8 is employed, the surface defect rate and the end surface defect rate of the donut glass substrate 4 are 0%. On the other hand, when a manual separation method is adopted, the surface defect rate is 2.0% and the end surface defect rate is 3.0%, and about 5% of the combined donut-shaped glass substrate is defective. . Therefore, by employing the separation method according to this embodiment, human error and variations among workers can be suppressed.

  Furthermore, when Example 2 and Examples 5-7 are compared, it turns out that a separation defect rate can be improved by adding 1 wt% or more of surfactant. This is considered to be due to the fact that the liquid has sufficiently penetrated into the interface between the bonding agent F made of an ultraviolet curable resin and the doughnut-shaped glass substrate 4 to improve the slipperiness. Therefore, when adding a surfactant, it is desirable that the addition amount be 1 wt% or more.

(Examples 9 to 11)
Moreover, about the bonding agent F used for the manufacturing method of the glass substrate by one Embodiment mentioned above, a dynamic viscoelasticity test is carried out using a dynamic viscoelasticity measuring machine (the SII company make, viscoelasticity spectrometer DMS6100), and joining is carried out. The temperature range of the liquid in the water tank 51 suitable for peeling of the agent F was derived. The test conditions were such that the distance between the marked lines was 20 mm by a tension method, the frequency was 1 Hz, the amplitude was 10 μm, the temperature of the liquid was changed from −50 to 200 ° C. at a rate of temperature increase of 2 ° C./min. . Further, according to the knowledge of the present inventor, the range of the elastic modulus E suitable for the peeling of the bonding agent F is 1.00 × 10 ⁵ (MPa) or more and 1.00 × 10 ¹⁰ (MPa) or less.

As a result, as Example 9, with respect to the glass transition temperature Tg of the bonding agent F made of an ultraviolet curable resin, the temperature of the liquid in the water tank 51 is Tg-30 ° C. (for example, 8 ° C.). The elastic modulus was 1.6 × 10 ⁹ (MPa). Further, as Example 10, the elastic modulus of the bonding agent F when the temperature of the liquid in the water tank 51 was Tg (for example, 38 ° C.) was 3.2 × 10 ⁷ (MPa). Furthermore, as Example 11, the elastic modulus of the bonding agent F when the temperature of the liquid in the water tank 51 was Tg + 30 ° C. (for example, 68 ° C.) was 6.0 × 10 ⁶ (MPa).

From the results of Examples 9 to 11 described above, in order to set the elastic modulus of the bonding agent F to 1.00 × 10 ⁵ to 1.00 × 10 ¹⁰ (MPa), the temperature of the liquid in the water tank 51 is set to Tg. It was confirmed that the temperature is preferably −30 ° C. or more and Tg + 30 ° C. or less, specifically, for example, 8 ° C. or more and 68 ° C. or less.

  According to the embodiment of the present invention described above, water or a liquid obtained by adding a surfactant to water is stored in the donut-shaped glass block 3 in which a plurality of donut-shaped glass substrates 4 are stacked with a spacer interposed therebetween. The doughnut-shaped glass substrate 4 is separated by the first arm 58 and the suction plate 59 and stored in the disc holder 54 by the first arm 58 and the suction plate 59, and the predetermined pressure by the roller 62 a is applied to the spacer by the second arm 62. The spacer is separated from the doughnut-shaped glass substrate 4 by sweeping while applying the pressing force, thereby producing the donut-shaped glass substrate 4 having extremely low surface defect rate and end surface defect rate and no chipping or surface scratches. It becomes possible. Further, according to one embodiment of the present invention, when the spacer and the glass substrate are firmly fixed, or when the outer diameter of the spacer and the outer diameter of the glass substrate are substantially the same, it causes the peeling. Even when there is no gap along the radial direction in the outer peripheral portion of the spacer, the spacer and the glass substrate can be easily separated.

  Although one embodiment of the present invention has been specifically described above, the present invention is not limited to the above-described embodiment, and various modifications based on the technical idea of the present invention are possible. For example, the numerical values given in the above-described embodiment are merely examples, and different numerical values may be used as necessary.

  In the above-described embodiment, an ultraviolet curable resin is used as the bonding agent F. However, a bonding agent such as a thermosetting resin, wax, glue, or adhesive, a paper or a nonwoven fabric with a bonding agent, Alternatively, a plastic tape or the like can be used. In addition, by using resin spacers such as UV curable resins and thermosetting resins, glass blocks can be easily manufactured and the spacers and the glass substrate can be fixed with appropriate strength. Becomes easy.

  Moreover, in the above-mentioned one embodiment, when forming the doughnut-shaped glass block 3, a double core grindstone in which an inner diameter processing grindstone and an outer diameter processing grindstone are arranged on the same axis is used. It is also possible to use a grindstone provided only with an outer diameter processing grindstone. Moreover, you may grind the glass block 1 in various shapes, such as a rectangle and a polygon, according to the shape of the glass substrate as a final product.

  In the above-described embodiment, when the plurality of separation storage devices 50 are arranged side by side, the water tank 51, the water flow generation unit 53, and the control unit 70 are used in common, but the position sensor 60 and the pressure sensor are further used. 61 may be used in common across a plurality of units.

DESCRIPTION OF SYMBOLS 1 Glass block 2 Thin plate 3 Donut-shaped glass block 4 Donut-shaped glass substrate 31, 42 Circular hole 41 Main surface 43 Outer peripheral end surface 44 Inner peripheral end surface 45 Outer peripheral edge portion 46 Inner peripheral edge portion 50 Separation storage device 51 Water tank 52 Work fixing Tool 52a Sliding contact portion 53 Water flow generating portion 53a Piping 53b, 57, 63 Pump 54 Disc holder 55 Linear guide 56 Cylinder 58 First arm 59 Suction plate 60 Position sensor 61 Pressure sensor 62 Second arm 62a Roller 64 Air cylinder 70 Control portion 101 Spindle 102 Double core grinding wheel 103 Fixing means 104 Fixing base F Bonding agent

Claims (10)

A predetermined-shaped glass block forming step of forming a predetermined-shaped glass block in which a plurality of predetermined-shaped glass substrates are laminated with each other via a spacer;
A glass substrate separation step of separating the outermost glass substrate from the predetermined shape glass block in a state where at least an interface portion between the glass substrate and the spacer is immersed in a liquid;
In a state where at least the interface portion between the spacer and the glass substrate is immersed in a liquid, a predetermined pressure is applied to the spacer on the outermost layer of the predetermined shape glass block, and the spacer is directed from one end to the other end. A spacer peeling step of peeling the outermost layer spacer from the glass block by sweeping the sweeping means,
The manufacturing method of the glass substrate characterized by including.   2. The glass substrate manufacturing method according to claim 1, further comprising a sliding contact step of sliding a separation surface separated from the glass block having the predetermined shape on the glass substrate to a sliding contact means after the glass substrate separation step. Method. Wherein the predetermined pressure, a manufacturing method of a glass substrate according to claim 1 or 2, characterized in that 0.4gf / mm ² or more 40 gf / mm ² or less. The method for producing a glass substrate according to any one of claims 1 to 3, wherein an elastic modulus of the spacer in the separation step is 1.00 x 10 ⁵ MPa to 1.00 x 10 ¹⁰ MPa. .   The method for producing a glass substrate according to any one of claims 1 to 4, wherein the liquid is water or water containing 1% by weight or more of a surfactant.   The method of manufacturing a glass substrate according to any one of claims 1 to 5, wherein the sweeping means has an arm having a roller made of hard rubber attached to the tip.   The said predetermined shape glass block formation process includes the process of forming the glass block which laminated | stacked the some thin glass through the spacer, and the process of cutting the said glass block to a predetermined shape, It is characterized by the above-mentioned. The manufacturing method of the glass substrate of any one of 1-6. In a glass substrate manufacturing apparatus configured to be separable from a predetermined shape glass block in which a plurality of glass substrates having a predetermined shape are laminated with a spacer therebetween, into glass sheets,
A liquid storage means for storing a liquid in a state where at least an interface portion between the glass substrate and the spacer can be immersed;
A glass substrate separating means configured to be capable of separating the outermost glass substrate from the predetermined shape glass block;
With respect to the predetermined shape glass block from which the glass substrate of the outermost layer has been separated, while applying a predetermined pressure to the spacer of the outermost layer of the predetermined shape glass block, from one end portion to the other end portion of the spacer And sweeping means configured to be swept by
An apparatus for manufacturing a glass substrate, comprising:   The apparatus for manufacturing a glass substrate according to claim 8, further comprising sliding contact means configured to be capable of sliding contact with a separation surface of the glass substrate separated from the spacer by the glass substrate separating means. .   The apparatus for producing a glass substrate according to claim 8 or 9, wherein the sweep means has an arm having a roller made of hard rubber attached to the tip.

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