JP2014188729A - Scribing wheel, scribing device, and method of manufacturing scribing wheel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a scribing wheel which hardly chips a cutting edge when using a scribing wheel formed with a plurality of grooves at the cutting edge by grind-wheel machining, a scribing device, and a method of manufacturing a scribing wheel.SOLUTION: A scribing wheel is formed with grooves 44 at a cutting edge 43. The grooves 44 are formed by bent curve portions 46, first straight line portions 47a extending from one ends of the curve portions to cutting edges 43 on one side, and second straight line portions 47b extending from the other ends of the curve portions 46 to cutting edges 43 on the other side.

Description

  The present invention relates to a scribing wheel, a scribing device, and a method for manufacturing a scribing wheel for forming a scribe line on a brittle material substrate such as a glass substrate.

  As a scribing wheel for dividing a brittle material substrate, there is known a scribing wheel in which a plurality of grooves are formed at the edge of a ridge line portion. As a method of forming this groove, a method of forming with a laser beam as described in Patent Document 1 and a method of forming using a grindstone are known.

JP 2009-234874 A

  However, when the groove is formed by laser light, it is necessary to irradiate the laser light deeper to deepen the groove. For this reason, in the method of irradiating with laser light, it is practically difficult to form a deep groove (about 6 μm or more).

  On the other hand, when the groove is formed using a grindstone, the groove can be easily deepened as compared with the case where the groove is formed by laser light. However, in general, a groove formed using a grindstone has a U-shaped curved shape. Therefore, the deeper the groove, the sharper the edge of the blade edge (the corner between the ridge line and the groove). When the edge part of the blade edge becomes sharp, this edge part is easily chipped during scribing, and the problem of the vertical crack extending during scribing due to the chipping of the edge part occurs.

  On the other hand, if the groove is formed without changing the depth of the groove so that the end of the blade edge is not so sharp, the width of the groove is increased. However, the relationship between the groove width and the groove depth in the scribing wheel is very important. The scribing performance of the scribing wheel varies greatly depending on the relationship between the groove width and the groove depth. In particular, if the groove width becomes too large relative to the groove depth, not only the vertical cracks will extend, but also the cracks will extend greatly in the horizontal direction and the line width of the scribe line will increase. Become.

  An object of the present invention is to provide a scribing wheel, a scribing device, and a manufacturing method of a scribing wheel that suppresses chipping of the cutting edge when using a scribing wheel in which a plurality of grooves are formed on the cutting edge by grinding wheel processing.

  In order to achieve the above object, a scribing wheel according to one aspect of the present invention is a scribing wheel that alternately includes a ridge line portion serving as a cutting edge and a groove formed by grinding stone processing, and the groove is a curved curve. Part, a first straight line portion extending from one end of the curved portion to one ridge line portion, and a second straight line portion extending from the other end of the curved portion to the other ridge line portion. .

  Such a scribing wheel makes it possible to increase the angle of the edge of the blade edge compared to a conventional scribing wheel formed with a U-shaped groove by grinding with a grindstone. Can be suppressed.

  In order to achieve the above object, in the scribing wheel, the groove has a depth of 2 μm or more, a width of the groove in a side view direction is 35 μm or less, and is 2.4 times the depth of the groove. It is characterized by the following.

  With such a scribing wheel, it is possible to suppress an increase in the line width of the scribe line while suppressing the chipping at the edge of the blade edge while maintaining high permeability to the brittle material substrate.

  In order to achieve the above object, the scribing device of the present invention is a scribing wheel that alternately includes a ridge line portion serving as a cutting edge and a groove formed by grinding stone processing, wherein the groove includes a curved curved portion and the curved portion. A scribing wheel formed by a first straight line portion extending from one end of the curved portion to one ridge line portion, and a second straight line portion extending from the other end of the curved portion to the other ridge line portion, and the scribing wheel being rotatable A holding pin, and a holder including a pair of support portions that form a holding groove in which the scribing wheel is disposed, and a pin hole in which the pin is disposed in the pair of support portions. Features.

  Such a scribing device can reduce the number of replacements of the scribing wheel as compared with a scribing device including a scribing wheel in which a groove that is curved in a U-shape is formed by grinding with a grindstone as in the prior art.

  Moreover, in order to achieve the said objective, the manufacturing method of the scribing wheel of this invention is a manufacturing method of the scribing wheel provided alternately with the ridgeline part used as a blade edge, and the groove | channel formed by the grindstone process using a disk-shaped grindstone. The tip of the grindstone is a curved grindstone curve portion, a first grindstone straight portion extending from one end of the grindstone curve portion toward one side of the grindstone, and the other end of the grindstone curve portion. Curved groove curve by using the grindstone formed by the second grindstone linear portion extending toward the other side surface of the grindstone and bringing the tip of the grindstone into contact with the circumference of the disk-shaped base material And a second groove linear portion extending from the other end of the groove curve portion to the other ridge line portion, and a second groove linear portion extending from the other end of the groove curve portion to the other ridge line portion. It is characterized by including the process to do.

  Such a scribing wheel manufacturing method can provide a scribing wheel having a long life.

It is a schematic diagram of a scribing device in an embodiment. It is a front view of the holder joint which the scribe device in an embodiment has. It is a perspective view of the holder unit in an embodiment. It is a partially expanded view of the holder unit in the embodiment. FIG. 5A is a side view of the scribing wheel in the embodiment, and FIG. 5B is a front view of the scribing wheel. FIG. 6A is a partially enlarged view of the scribing wheel in the embodiment, and FIG. 6B is a partially enlarged view of the scribing wheel for comparison. It is a conceptual diagram of the manufacturing method of the scribing wheel in embodiment. It is an enlarged photograph of the scribing wheel in an embodiment. 9A is a plan view and an enlarged view of the mother substrate, FIG. 9B is a cross-sectional view taken along line IXb-IXb in FIG. 9A, and FIG. 9C is a view in FIG. 9B. It is sectional drawing which divided the mother board | substrate. It is sectional drawing of a display apparatus. It is a table | surface regarding the scribing wheel of Experimental Examples 1-8. It is a table | surface of the scribe result regarding the scribing wheel of Experimental Examples 1-8. It is a graph of the line width of the scribe line formed with the scribing wheel of Experimental Examples 1-8. It is the photograph of the scribe line formed using the scribing wheel of Experimental example 1, Experimental example 4, and Experimental example 6. It is a graph of the length of the crack of the scribe line formed with the scribing wheel of Experimental Examples 1-8.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiment shown below shows an example for embodying the technical idea of the present invention, and is not intended to specify the present invention to this embodiment. The invention is also applicable to other embodiments within the scope of the claims.

  A schematic diagram of a scribing apparatus 10 according to the embodiment is shown in FIG. The scribing apparatus 10 includes a moving table 11. The moving table 11 is screwed with the ball screw 13 and can be moved in the y-axis direction along the pair of guide rails 12a and 12b by rotating the ball screw 13 by driving the motor 14. ing.

  A motor 15 is installed on the upper surface of the movable table 11. This motor 15 is for rotating the table 16 located in the upper part on an xy plane and positioning it at a predetermined angle. The brittle material substrate 17 is placed on the table 16 and held by a vacuum suction means (not shown). Note that the brittle material substrate 17 to be scribed is a brittle material substrate such as a glass substrate, a ceramic substrate, a sapphire substrate, or a silicon substrate.

  The scribing apparatus 10 includes two CCD cameras 18 that image the alignment marks formed on the surface of the brittle material substrate 17 above the brittle material substrate 17. And in the scribe device 10, the bridge 19 is constructed by the support | pillars 20a and 20b along the x-axis direction so that the movable stand 11 and the table 16 of the upper part may be straddled.

  A guide 22 is attached to the bridge 19, and a scribe head 21 is installed along the guide 22 so as to be movable in the x-axis direction. A holder unit 30 is attached to the scribe head 21 via a holder joint 23.

  FIG. 2 is a front view of the holder joint 23 to which the holder unit 30 is attached. FIG. 3 is a perspective view of the holder unit 30. 4 is an enlarged view of a part of the side surface of the holder unit 30 observed from the direction A in FIG.

  The holder joint 23 has a substantially cylindrical shape, and includes a rotation shaft portion 23a and a joint portion 23b. In a state where the holder joint 23 is attached to the scribe head 21, two bearings 24a and 24b for rotatably holding the holder joint 23 are provided on the rotary shaft portion 23a via a cylindrical spacer 24c. It is attached. FIG. 2 shows a front view of the holder joint 23 and also shows a sectional view of the bearings 24a and 24b and the spacer 24c attached to the rotary shaft portion 23a.

  The cylindrical joint portion 23b is provided with an internal space 26 having a circular opening 25 on the lower end side. A magnet 27 is embedded in the upper portion of the internal space 26. A holder unit 30 that is detachable by a magnet 27 is inserted into the internal space 26 and attached.

  The holder unit 30 is a unit in which a holder 30a, a scribing wheel 40, and a pin 50 are integrated. As shown in FIG. 3, the holder 30a has a substantially cylindrical shape and is made of a magnetic metal. And the attaching part 31 for positioning is provided in the upper part of the holder 30a. The attachment portion 31 is formed by cutting out the upper portion of the holder 30a, and includes an inclined portion 31a and a flat portion 31b.

  Then, the attachment portion 31 side of the holder 30 a is inserted into the internal space 26 through the opening 25. At that time, the upper end side of the holder 30a is attracted by the magnet 27, and the inclined portion 31a of the mounting portion 31 comes into contact with the parallel pin 28 passing through the internal space 26, whereby the holder unit 30 is positioned and fixed with respect to the holder joint 23. . Further, when removing the holder unit 30 from the holder joint 23, the holder unit 30 can be easily removed by pulling it downward.

  A holding groove 32 formed by cutting out the holder 30a is provided below the holder 30a. The support portions 33a and 33b are located below the holder 30a that is notched to provide the holding groove 32 with the holding groove 31 interposed therebetween. A scribing wheel 40 is rotatably disposed in the holding groove 32. The support portions 33a and 33b are respectively formed with support holes 34a and 34b for supporting the pins 50 for holding the scribing wheel 40 freely during rotation.

  Then, as shown in FIG. 4, the pin 50 is passed through the pin hole 45 of the scribing wheel 40, and the both ends of the pin 50 are installed in the support holes 34a and 34b, so that the scribing wheel 40 is attached to the holder 30a. It will be attached to rotate freely. The support hole 34a has a stepped portion inside, and the hole diameter of the opening on the holding groove 32 side is larger than the hole diameter of the opening on the other side.

  Next, the details of the scribing wheel 40 will be described. FIG. 5A is a side view of the scribing wheel 40, and FIG. 5B is a front view of the scribing wheel 40. FIG. 6A is an enlarged view of a portion indicated by a circle B in FIG. FIG. 6B is an enlarged view of a scribing wheel for comparison.

  The scribing wheel 40 mainly has a main body 41, a blade 42, a blade edge 43, and a groove 44.

  The main body 41 has a disk shape. In the vicinity of the center of the main body 41, a through hole 45 that penetrates the main body 41 along the rotation axis is provided. A pin 50 is inserted into the through hole 45, and the scribing wheel 40 is rotatably held by the holder 30 a via the pin 50. An annular blade 42 is formed on the outer periphery of the main body 41.

  The blade 42 is an annular body formed by concentric inner and outer peripheries around the rotation axis. The blade 42 is substantially V-shaped when viewed from the front, and the thickness of the blade 42 along the rotation axis is gradually reduced toward the blade edge 43 serving as the ridge line portion. That is, the blade 42 is composed of inclined surfaces on both sides of the ridge line that becomes the blade edge 43.

  The blade edge 43 is provided along the outermost periphery of the blade 42. In the outermost peripheral portion of the blade 42, the blade edge 43 and the groove 44 are alternately formed. FIG. 6B shows a scribing wheel blade 142, a blade edge 143, and a groove 144 for comparison.

  As shown in FIG. 6A, the groove 44 is different from the groove 144 formed only by a curved shape such as a U shape as shown in FIG. 6B, and the tip which is the bottom of the groove has a parabolic shape. It is constituted by a V-shape that is curved in a straight line. That is, the groove 44 has a curved portion 46 that is curved around the portion where the depth of the groove 44 is deepest, and a first straight portion 47a that extends from the end of the curved portion 46 toward the cutting edge 43 on one side. And a second linear portion 47b extending toward the other blade edge 43.

  By configuring the groove 44 with the curved portion 46 and the straight portions 47a and 47b, the angle of the end portion of the blade edge 43 can be increased as compared with the end portion of the blade edge 143 of the groove 144. Therefore, when the cutting edge 43 comes into contact with the brittle material substrate 17, the end of the cutting edge 43 is hardly chipped, and the replacement life of the scribing wheel 40 is extended.

  In addition, since the tip which becomes the bottom of the groove 44 is curved, the scribing wheel 40 is compared with a scribing wheel having a V-shaped groove whose tip is simply bent as in the case where the groove is formed by laser processing. The cullet generated by scribing is unlikely to collect at the bottom of the groove.

  In FIG. 6A, the ratio of the linear portion 47a, the curved portion 46, and the linear portion 47b indicated by a, b, and c in the width L of the groove 44 is a: b: c = 1: 1: 1. It is about ˜1: 2: 1. In the present embodiment, the straight portions 47 a and 47 b extending from both ends of the curved portion 46 are tangent lines at the end of the curved portion 46. Details of the processing method and size of the groove 44 will be described later.

  The scribing wheel 40 is made of cemented carbide or sintered diamond. The scribing wheel 40 may be a base material such as cemented carbide coated with a film of a hard material such as diamond.

  For example, the sintered diamond scribing wheel 40 is mainly made of diamond particles and a binder phase composed of the remaining additive and binder. The diamond particles having an average particle size of 1.5 μm or less are used. And the diamond content in the sintered diamond is in the range of 75.0-90.0 vol%.

  As the additive, for example, an ultrafine carbide of at least one element selected from tungsten, titanium, niobium, and tantalum is preferably used. The content of ultrafine carbide in the sintered diamond is in the range of 3.0 to 10.0 vol%, and the ultrafine carbide comprises 1.0 to 4.0 vol% titanium carbide and the balance tungsten carbide. Including.

  As the binder, an iron group element is usually preferably used. Examples of the iron group element include cobalt, nickel, iron and the like, and among these, cobalt is preferable. Further, the content of the binder in the sintered diamond is preferably the balance of diamond and ultrafine carbide, and more preferably in the range of 3.0 to 20.5 vol%.

  Next, a method for manufacturing the scribing wheel 40 will be described. First, the above-mentioned diamond particles, additives, and binder are mixed, and the mixture is sintered at a high temperature and ultrahigh pressure at which diamond is thermodynamically stable. As a result, sintered diamond is produced. During this sintering, the pressure in the mold of the ultrahigh pressure generator is in the range of 5.0 to 8.0 GPa, and the temperature in the mold is in the range of 1500 to 1900 ° C.

  Next, a disk having a desired radius is cut from the manufactured sintered diamond. And in the peripheral part of the disk used as this base material, the scribing wheel 40 which forms an inclined surface by cutting each both-surfaces side, and has the blade 42 of a V-shaped cross section can be made.

  And by making the disk-shaped grindstone orthogonal to the ridgeline which consists of the blade edge | tip 43 of this scribing wheel 40 contact the blade edge | tip 43, the curve part 46 as shown to Fig.6 (a), and the linear part 47a. , 47b are formed.

  A specific manufacturing method for providing such a groove 44 is shown in FIG. The groove 44 is formed by a grinding unit 80 having a disk-shaped grindstone 81. Specifically, the grinding unit 80 is configured such that the disk-shaped grindstone 81 is rotated in the direction of the arrow K by the motor M.

  First, the scribing wheel 40 is rotated in the direction of arrow J by a certain angle. Next, the groove 44 is formed by pushing up the scribing wheel 40 in the direction of the arrow U and bringing it into contact with the tip 82 of the grindstone 81 rotating right above the scribing wheel 40. When the groove 44 is formed, the scribing wheel 40 is retracted in the direction of arrow D. Next, after the scribing wheel 40 is rotated by a rotation angle corresponding to a predetermined pitch, the next groove 44 is formed by pushing up the scribing wheel 40 in the arrow U direction.

  That is, by repeating the contact of the cutting edge 43 with the tip 82 of the grindstone 81 while rotating the scribing wheel 40 by a certain angle in the direction of arrow J, the cutting edge 43 and the groove as shown in FIG. The scribing wheel 40 in which 44 and 44 are alternately continued is completed.

  Here, the tip 82 of the grindstone 81 is formed in a V-shape with a tip that is curved, as shown in an enlarged view in FIG. That is, the tip 82 includes a curved grindstone curve portion 83, a first grindstone straight portion 84 a extending from one end of the grindstone curve portion 83 toward one side surface of the grindstone 81, and the other end of the grindstone curve portion 83. The second grindstone linear portion 84b extends toward the other side surface of the grindstone 81. The shape of the tip portion 82 is formed and maintained by dressing processing or the like on both side surfaces of the grindstone 81.

  Then, the curved portion 46 of the groove 44 is formed using the grindstone curved portion 83 by bringing the cutting edge 43 into contact with the tip portion 82 by a distance (indicated by h in FIG. 7) corresponding to the depth H of the groove 44. Then, a straight portion 47a of the groove 44 is formed using a part of the grindstone straight portion 84a, and a straight portion 47b of the groove 44 is formed using a portion of the grindstone straight portion 84b, as shown in FIG. The groove 44 shown is completed. In the present embodiment, since the grooves 44 are formed in a single process using the grindstone 81, the plurality of grooves 44 can be formed efficiently.

  A photograph of the scribing wheel 40 provided with the grooves 44 formed in this way is shown in FIG. In the actually manufactured scribing wheel 40, the grooves 44 are formed by using the grinding unit 80, so that diamond particles may be chipped during polishing with the grindstone 81. Therefore, since some unevenness is generated on the surface of the groove 44, the straight portions 47a and 47b have some unevenness. Further, the end portion x that is the intersection of the straight portions 47a and 47b and the blade edge 43 as shown in FIG. 6A is not always clearly observable.

  Next, the dimensions of the scribing wheel 40 will be described. The outer diameter Dm of the scribing wheel 40 is 1.0 to 10.0 mm, preferably 1.0 to 7.0 mm, and particularly preferably 1.0 to 5.0 mm. When the outer diameter Dm of the scribing wheel 40 is smaller than 1.0 mm, the handleability of the scribing wheel 40 is lowered. On the other hand, when the outer diameter Dm of the scribing wheel 40 is larger than 10.0 mm, the vertical crack at the time of scribing may not be formed deeply with respect to the brittle material substrate 17.

  Moreover, the thickness Th of the scribing wheel 40 is 0.4 to 1.2 mm, preferably 0.4 to 1.1 mm. When the thickness Th of the scribing wheel 40 is smaller than 0.4 mm, workability and handleability may be deteriorated. On the other hand, when the thickness Th of the scribing wheel 40 is larger than 1.2 mm, the material for the scribing wheel 40 and the cost for manufacturing increase.

  The blade edge angle θ1 of the blade 42 is usually an obtuse angle, and is in the range of 90 ≦ θ1 ≦ 160 (deg), preferably 90 ≦ θ1 ≦ 140 (deg). The specific angle of the blade edge angle θ1 is appropriately set based on the material, thickness, etc. of the brittle material substrate 17 to be cut.

  The groove 44 is formed so that the groove width L is 2.0 to 2.4 times as long as the groove depth H. In FIG. 6A, the state of the cutting edge 43 before forming the groove 44 in the scribing wheel 40 is indicated by a broken line. The depth H of the groove is the distance deepest from this imaginary line. Further, the width L of the groove is the length of an imaginary straight line connecting the end portions x of the grooves. The width W of the ridge line is the length of the cutting edge 43.

  The depth H of the groove is set according to the outer diameter of the scribing wheel 40 and the material and thickness of the brittle material substrate 17 to be cut. And the depth H of a groove | channel is set in the range of 2.0-14 micrometers, Preferably it is the range of 3.0-12.0 micrometers, More preferably, it is the range of 5.0-12.0 micrometers. If the groove depth H is smaller than 2.0 μm, it is difficult to form deep vertical cracks in the brittle material substrate. If the groove depth H is larger than 14 μm, the groove volume increases. Therefore, the crack extends not only in the vertical direction but also in the horizontal direction, and the line width due to the scribe is widened. The cracks in the horizontal direction are further extended over time, and a plurality of horizontal cracks are combined to inevitably generate a relatively large cullet. Further, since the length of the crack in the horizontal direction depends on the volume of the groove, the effect of setting the width L of the groove to 2.0 to 2.4 times the depth H of the groove is It becomes particularly large when the depth H is 5.0 μm or more.

  The width L of the groove is set in the range of 5.0 to 35 μm, preferably 7.0 to 30 μm, and more preferably 10 to 25 μm. When the groove width L exceeds 35 μm, the groove volume increases in the same manner, so that the width of the scribe line becomes wide and generation of a large cullet is unavoidable.

  The width W of the ridge line is preferably 10 to 30 μm. When the width of the ridge line is smaller than 10 μm, the load cannot be sufficiently transmitted to the substrate, and the vertical crack does not sufficiently penetrate. On the other hand, if the width of the ridge line is too wide, horizontal cracks are likely to occur.

  Further, the width L of the groove is preferably 1.0 to 3.2 times the width W of the ridge line, and more preferably 1.0 to 1.8 times. When it is smaller than 1 time, the vertical crack does not extend sufficiently, while when it is 3.2 times or more, the width of the scribe line is wide and the cullet becomes large.

  In addition, the edge angle θ2 of the blade edge 43 indicated by θ2 in FIG. 6A is preferably in the range of 115 ≦ θ2 ≦ 135 (deg). This is because if the edge angle becomes too large, the biting (hanging) on the brittle material substrate will deteriorate. On the other hand, if the edge angle θ2 is too small (approaching 90 °), the edge is very likely to be chipped.

  Here, the influence of the line width LW of the scribe line formed on the surface of the brittle material substrate when the brittle material substrate is divided using the scribing wheel will be described using a specific example. 9A is a plan view and an enlarged view of a mother substrate which is a brittle material substrate, FIG. 9B is a cross-sectional view taken along line IXb-IXb in FIG. 9A, and FIG. It is sectional drawing which divided the mother board | substrate in 9 (b). FIG. 10 is a cross-sectional view of the display device.

  The brittle material substrate on which a scribe line is formed on the substrate surface by the scribing wheel is a large glass substrate for manufacturing a display panel 60 such as a liquid crystal panel. This glass substrate is also called a mother substrate 70. Usually, a plurality of display panels 60 are manufactured at once using the mother substrate 70. Note that the plan view of the mother substrate shown in FIG. 9A is not the entire mother substrate but only a part thereof.

  First, as shown in FIG. 9A, pixels and the like are formed on the mother substrate 70 for each display panel 60. Specifically, the display panel 60 includes a display area 61 and a frame area 62 around the display area 61, and a plurality of pixels including switching elements, color filters, and the like are formed in the display area 61. In the frame area 62, wiring for transmitting various signals to each pixel in the display area 61, external connection terminals, and the like are formed.

  Next, as shown in FIGS. 9A and 9B, a scribing wheel in which a load is applied along the boundary of the display panel 60 in the mother substrate 70 in which pixels and the like are formed for each display panel 60. 40 is rotated. Thereby, a scribe line 71 is formed on the surface of the mother substrate 70. The scribe line 71 is composed of a plastic deformation region and a horizontal crack caused by the load of the scribing wheel 40 on the surface of the mother substrate 70.

  Then, as shown in FIG. 9B, by forming the scribe line 71, the vertical crack 72 extends from the approximate center of the scribe line 71 in the vertical direction of the mother substrate 70 along the scribe line 71.

  Next, by applying stress to the mother substrate 70 on which the scribe lines 71 and the vertical cracks 72 are formed, the mother substrate 70 is divided into the display panel 60 as shown in FIG. Is completed.

  Then, as shown in FIG. 10, the frame area 62 of the display panel 60 is covered with a frame-shaped outer frame 73, and a control board or the like (not shown) is connected to the display panel 60. Manufactured.

  Here, if the line width LW of the scribe line 71 formed on the mother substrate 70 is increased, the following problem may occur.

  First, as shown in FIG. 9C, the scribe lines 71 are formed on the surface of the substrate end portion of the display panel 60 at a ratio of about half the line width LW even after being divided into the display panel 60. It remains as 71a. There is no problem if the frame width a of the frame region 62 is sufficiently wide. However, when the frame width a becomes narrow due to the narrowing of the frame, the ratio of the scribe marks 71a in the frame width a increases. For this reason, even if the scribe mark 71a is completely covered by the outer frame 73 from the front direction, when the display device 74 is observed from an oblique direction, the scribe mark 71a can be directly seen or irregular reflection occurs in the scribe mark 71a. There may be a problem that the scribe mark 71a is noticeable.

  Further, if the frame width a is increased in order to prevent the scribe marks 71a from being observed, there arises a problem that the number of display panels 60 manufactured by the mother substrate 70 is reduced. Further, when the width of the outer frame 73 is increased, problems such as an increase in cost and the outer frame 73 overlapping the display area 61 occur.

  In addition, even after the display device 74 is formed, if many scribe marks 71a including the scribe lines 71 remain on the surface of the substrate end portion of the display panel 60, the horizontal cracks are eventually connected to each other due to vibration or the like, and a small piece cullet. There is a risk that wiring will be damaged by this caret. Therefore, if the scribe mark 71a remaining on the display panel 60 is to be completely removed, another process such as polishing is required, resulting in an increase in cost.

  Further, if the display panel 60 is made by bonding two mother substrates 70 like a liquid crystal panel, wiring or the like is formed on the same surface as the surface on which the scribe line 71 is formed. Therefore, the formation of the scribe line 71 is less likely to cut the wiring or the like. However, if the display panel 60 is configured such that a single mother substrate 70 is used and wirings and the like are directly formed on the same surface as the surface of the mother substrate 70 on which the scribe line 71 is formed, the scribe line 71 is used. There is also a risk that the wiring and the like may be cut by the formation of.

  The above problems can be solved by suppressing the spread of the line width LW of the scribe line 71 formed on the surface of the mother substrate 70 and reducing the line width LW as much as possible.

  Therefore, as a scribing method for suppressing the spread of the line width of the scribe line, in this embodiment, the groove 44 has a curved portion 46 and a straight portion 47a extending from one end of the curved portion 46 toward one blade edge 43, And a straight line portion 47b extending from the other end of the curved portion 46 toward the other cutting edge 43, the depth H of the groove 44 is 2 μm or more, and the width L of the groove 44 is A scribing wheel 40 having a diameter of 35 μm or less and having a depth H of 2.4 times or less is applied, and a scribe line is formed by applying a load to the scribing wheel 40 and rotating the surface of the brittle material substrate 17. Went the way. By this scribing method, it was possible to prevent the cutting edge 43 from being chipped and to suppress the spread of the line width of the scribe line, thereby realizing a scribe line having a narrow line width.

  A specific result of dividing the brittle material substrate 17 by the scribing method of this embodiment will be described. The scribing wheel used was that of Experimental Examples 1-8. The scribing wheels of Experimental Examples 1 to 8 all had an outer diameter Dm of 2.0 mm, a thickness Th of 0.65 mm, and a cutting edge angle θ1 of 100 °. FIG. 11 is a table describing other elements of Experimental Examples 1-8. FIG. 11 illustrates the groove depth H, the groove width L, the ridge line width W, the number of protrusions, L / H, and L / W in Experimental Examples 1 to 8.

  Here, among the scribing wheels of Experimental Examples 1 to 8, Experimental Examples 1 to 5 are scribing wheels having a groove shape that is simply curved like a U-shape as shown in FIG. is there. On the other hand, in Experimental Examples 6 to 8, a scribing wheel as shown in FIG. 6A is a scribing wheel in which the shape of the groove is composed of a curved portion and two straight portions extending from both ends of the curved portion toward the cutting edge. It is. Moreover, as shown in FIG. 9, the scribing wheel in which the groove width L is 2.0 to 2.4 times longer than the groove depth H is the scribing wheel of Experimental Examples 6 to 8. The scribing wheels 1 to 5 have L / H larger than 2.4 times.

  Then, using the scribing wheels of Experimental Examples 1 to 8, a scribe line was formed while applying a load to these scribing wheels and rotating the surface of the brittle material substrate. FIG. 12 is a table of scribing results using the scribing wheels of Experimental Examples 1 to 8. In FIG. 12, the cutting area | region of the scribing wheel of Experimental Examples 1-8, the line width LW of the scribe line made in the brittle material board | substrate, and the length of a crack are shown.

  This cutting region is a load region in which a good scribe line can be formed when cutting a brittle material substrate. In this load area, the minimum load is measured based on the occurrence of rib-shaped streaks called rib marks, and the maximum load from the minimum load at which a good scribe line cannot be formed due to an increase in horizontal cracks, cracks in the substrate, etc. It is a measured value.

  As shown in FIG. 12, the cutting region differs depending on the scribing wheel of Experimental Examples 1 to 8, and the scribing wheel of Experimental Examples 2 to 8 has a lower minimum load in the cutting region than that of Experimental Example 1. . Among them, in Experimental Examples 6 to 8, the minimum load is low.

  In addition, as shown in FIG. 12, the load which formed the scribe line for the line width LW measurement is a load obtained by adding 1N to the minimum load (Min) of the cutting region (therefore, the load varies depending on each scribing wheel), There were three patterns of 10N load and 15N load.

  The line width LW is the maximum value of horizontal cracks formed on the brittle material substrate surface. The line width LW was measured with each of the three loads. FIG. 13 is a graph showing the measured line width LW. FIG. 14 is an actual photograph of a scribe line formed using the scribing wheels of Experimental Example 1, Experimental Example 4, and Experimental Example 6.

  The length of the crack is the maximum value of the vertical crack formed in the brittle material substrate. The crack length was also measured at each of the three loads. FIG. 15 is a graph showing the measured crack length.

Other conditions when scribing using the scribing wheels of Experimental Examples 1 to 8 are as follows.
Brittle material substrate: 0.7 mm glass substrate (single plate, bare glass)
Scribing device: scribing device made by Samsung Diamond Industrial Co., Ltd. (MS type)
Scribe speed: 300mm / sec

  First, as shown in FIGS. 11 to 15, when scribing was performed using the scribing wheel (L / H 3.8) of Experimental Example 1 where L / H is not 3.2 or less, L / H is 3 .2 The line width is wider than the scribing wheels of Experimental Examples 2 to 8 below.

  When the glass substrate for panels is divided, the line width LW of the scribe line is preferably up to about 30 μm. If the line width LW is 30 μm, the scribe mark 71a by the scribe line 71 shown in FIG. 10 is about 15 μm. If the scribe mark 71a is of this level, the scribe mark 71a is reduced even in a narrow frame. This is because problems such as visual recognition are less likely to occur.

  In the scribing wheels of Experimental Examples 2 to 8, the line width LW is approximately 30 μm at a low load (a Min + 1N load or a 10N load in FIG. 12) that is often set as an actual cutting load in the cutting region. It is suppressed.

  In particular, in the scribing wheels of Experimental Examples 6 to 8 where L / H is 2.4 or less, the line width LW is significantly narrower than 30 μm at low load.

  In the case of a load of 15 N, in Experimental Examples 1 to 5, the line width LW is suddenly widened. In Experimental Examples 6 to 8, the line width LW is approximately 30 μm, and the line width LW is The spread of the width LW is suppressed.

  Further, as shown in FIG. 15, even in the case of 6N (Min + 1N) with a low load, Experimental Examples 6 to 8 have a sufficient penetration amount of 70% or more with respect to the thickness of the substrate, particularly at a load of 10N. It can be seen that both have high permeability of 600 μm or more, which is not so different from other scribing wheels in Experimental Examples 1 to 5.

  Further, as shown in FIG. 11, regarding the relationship between the width L of the groove and the width W of the ridgeline, the L / W of the scribing wheel in Experimental Examples 1 to 4 is 2.0 or more, whereas Experimental Examples 6 to 8 Each of the scribing wheels has an L / W of less than 2.0. Further, as shown in FIGS. 11 and 13, the L / W of the scribing wheel is more preferably 1.8 or less in order to suppress the expansion of the line width.

  In this way, the groove is formed by a curved portion and two straight portions extending from both ends of the curved portion toward the cutting edge, the groove depth H is 2 μm or more, and the groove width L is 35 μm or less. By using the scribing wheel of Experimental Examples 6 to 8 where / H is 2.4 or less and applying a load to the scribing wheel to rotate the surface of the brittle material substrate to form a scribe line, It is possible to suppress the chip width and to suppress the spread of the line width LW of the scribe line while maintaining high permeability, and it is possible to realize a scribe line having a narrow line width.

  In addition, when the groove width L with respect to the groove depth H is further reduced as compared with Experimental Examples 6 to 8, for example, when L / H is 1.9, the line width of the scribe line is increased. Although it was possible to suppress, the fine cullet generated at the time of scribing enters the groove, and the cullet accumulates in the groove every time it is scribed, so the depth of the groove is substantially shallow, The amount of permeation gradually decreased.

  In the present embodiment, the scribing device 10 is provided with two CCD cameras 18 that image the alignment marks of the brittle material substrate 17 or a movable table that rotates a table on which the brittle material substrate 17 is placed. 11 is shown. However, the present invention is not limited to such a scribing device 10, and a brittle material is attached by attaching a holder that rotatably holds the scribing wheel to the tip of the handle, and the user moves the handle with the handle. Even a so-called manual scribing apparatus that divides the substrate 17 is applicable.

DESCRIPTION OF SYMBOLS 10 ... Scribing device 11 ... Moving stand 12a, 12b ... Guide rail 13 ... Hall screw 14, 15 ... Motor 16 ... Table 17 ... Brittle material substrate 18 ... CCD camera DESCRIPTION OF SYMBOLS 19 ... Bridge 20a, 20b ... Post 21 ... Scribe head 22 ... Guide 23 ... Holder joint 23a ... Rotary shaft part 23b ... Joint part 24a, 24b ... Bearing 24c ... Spacer 25 ... Opening 26 ... Internal space 27 ... Magnet 28 ... Parallel pin 30 ... Holder unit 30a ... Holder 31 ... Mounting part 31a ... Inclined part 31b ... Flat part 32 ... Holding groove 33a, 33b ... Support part 34a, 34b ... Support hole 40 ... Scribing wheel 41, 41a ... base material 41 ... main body 42, 142 ... blade 43, 143 ... blade edge 44, 144 ... groove 45 ... through hole 46 ... curved portion 47a, 47b ... Linear part 50 ... Pin 60 ... Display panel 61 ... Display area 62 ... Frame area 70 ... Mother substrate 71 ... Scribe line 71a ... Scribe mark 72 ... · Vertical crack 73 · · · Outer frame 74 · · · Display device 80 · · · Grinding unit 81 · · · Grinding wheel 82 · · · Tip portion 83 · · · Grinding stone curve portion

Claims (6)

A scribing wheel provided alternately with ridge lines that are cutting edges and grooves formed by grinding stones,
The groove is formed by a curved curved portion, a first straight portion extending from one end of the curved portion to one ridge line portion, and a second straight portion extending from the other end of the curved portion to the other ridge line portion. A scribing wheel characterized by   2. The scribing wheel according to claim 1, wherein ratios of the first straight portion, the curved portion, and the second straight portion in the width of the groove are equal.   The depth of the groove is 2 μm or more, and the width of the groove in a side view direction is 35 μm or less and is 2.4 times or less of the depth of the groove. The scribing wheel described in   The scribing wheel according to claim 3, wherein a width of the groove is 2.0 times or more of a depth of the groove. A scribing wheel according to any one of claims 1 to 4,
A pin for rotatably holding the scribing wheel;
A holder including a pair of support portions forming a holding groove in which the scribing wheel is disposed, and a pin hole in which the pin is disposed in the pair of support portions;
A scribing device comprising: A scribing wheel manufacturing method comprising alternately a ridge line portion serving as a cutting edge and a groove formed by grinding using a disc-shaped grinding wheel,
The tip of the grindstone has a curved grindstone curve portion, a first grindstone straight portion extending from one end of the grindstone curve portion toward one side of the grindstone, and the other end of the grindstone from the other end of the grindstone curve portion. A second grindstone linear portion extending toward the side surface of
By bringing the tip of the grindstone into contact with the circumference of a disk-shaped base material, a curved groove curve portion, a first groove straight portion extending from one end of the groove curve portion to one ridge line portion, and the groove The manufacturing method of the scribing wheel characterized by including the process of forming the said groove | channel consisting of the 2nd groove | channel linear part extended from the other end of a curve part to the other ridgeline part.