JP2010116272A - Glass substrate cutting device and glass substrate cutting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a glass substrate cutting method which prevents an uncut part from being formed in a cut end part in the cutting of the glass substrate by heating and cooling. <P>SOLUTION: The glass substrate cutting method includes: a groove-forming step of forming a cut starting groove on the starting edge of a cut scheduled line on the surface of the glass substrate and a cut ending groove on the termination of the cut scheduled line; and a crack line forming step of forming a crack line formed by extending the crack produced in the thickness direction of the glass substrate from the starting to the ending of the cut scheduled line by locally heating and cooling the glass substrate while scanning the surface of the glass substrate. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a glass substrate cutting device and a glass substrate cutting method, and more particularly to a cutting device and a cutting method for cutting a glass substrate by irradiating the glass substrate with laser light.

  In recent years, liquid crystal display panels have been widely used as display units for home appliances such as computers and televisions. In general, a liquid crystal display panel is formed by bonding a pair of glass substrates, which are a thin film transistor (TFT) array substrate and a color filter (CF) substrate, facing each other in parallel at a predetermined interval, and liquid crystal is interposed between the glass substrates. It has a sealed configuration.

  Usually, a plurality of pixel electrodes are formed in a matrix on the TFT array substrate, and a common electrode is formed on almost the entire surface of the CF substrate, and the orientation of the liquid crystal is controlled by changing the voltage applied between these electrodes. Can be done.

  In manufacturing such a liquid crystal display panel, a wiring pattern for a plurality of liquid crystal display panels is formed on a large mother glass substrate (a large glass substrate for obtaining a plurality of liquid crystal display panels). Until halfway, the process is performed with the mother glass substrate.

  Then, the mother glass substrates are bonded to each other to form a large panel, and then individually cut, or individually cut (a large liquid crystal display device or the like is usually divided into two to six) and then bonded. (See FIG. 5 (a) and FIG. 5 (b)).

  The former method of cutting after bonding is adopted for a small liquid crystal display panel used for a mobile phone or the like, and the latter method of bonding after cutting is adopted for a large liquid crystal display panel used for a liquid crystal television or the like.

  As a method for cutting such a glass substrate, a stress is applied so as to create a crack (streak-like scratch) with a hard and sharp object on the surface of the glass substrate, and to generate a crack extending from the groove to the back surface of the glass substrate. There is a way to divide.

  For example, the glass substrate 32 is scanned by scanning the wheel cutter 31 along the planned cutting line 32a while keeping the wheel cutter 31 as shown in FIG. 6A in contact with the surface of the glass substrate 32 with a predetermined force. A groove 33 is formed in the glass substrate, and then a bending stress is applied to the glass substrate 32, and the glass substrate 32 is cut by this stress.

  In the glass substrate 32 cut by such a method, as shown in FIG. 6B, a chipping 35 or a microcrack 36 may occur in the ridge line portion 34 a of the cut surface 34. Such micro cracks 36 and the like are considered to be caused by the residual stress in the microplastic deformation region of the glass generated on the cut surface 34.

  If such a microcrack 36 or the like is present on the cut surface 34 that is an end portion of the glass substrate 32, the glass substrate 32 is bent more greatly as it becomes larger. There is a problem that it easily breaks from the starting point (see FIG. 7A).

  In order to prevent such breakage of the glass substrate 32, chamfering is performed along the ridge line portion 34a of the cut surface 34 where the micro cracks 36 are generated, and the micro cracks 36 are removed. Is preferred.

  FIG. 7B is a diagram showing an example of such chamfering. As shown in the drawing, a grinding wheel 38 formed at an appropriate angle is attached to the rotary shaft 37, and the grinding wheel 38 is rotated in the rotation direction 39. By moving the grinding wheel 38 relative to the ridge line portion 34a of the cut surface 34 of the glass substrate 32 to form a chamfer 40 of an appropriate size, the microcracks 36 and the like are removed, and the cut surface 34 against the crack is removed. Strength can be secured.

  However, performing such chamfering on the cut surface 34 of the glass substrate 32 significantly reduces productivity. For example, the ridge line portion 34a of the glass substrate 32 is scraped to generate fine grinding powder, and this grinding powder adheres to the glass substrate 32. Therefore, a cleaning process is required after chamfering. In some cases, the firmly adhered grinding powder could not be removed by washing, causing defective products.

  Further, since the grinding wheel 38 is worn as the processing proceeds, and the machining shape of the chamfer 40 is impaired, maintenance for replacing the grinding wheel 38 regularly is required.

  Therefore, in recent years, there has been proposed a method of cutting a glass substrate by irradiating the glass substrate with a laser beam to locally heat it, and jetting cooling water to the region irradiated with the laser beam to cool it. Yes. When local heating and cooling are applied to the glass substrate, thermal distortion (thermal expansion and contraction) occurs in that part, and when the stress due to this thermal strain exceeds the bonding force of the glass molecules, the bonding of the glass molecules is broken. As a result, a crack in the thickness direction of the glass substrate occurs.

  When cutting by causing a crack in the thickness direction of the glass substrate by the cutting method by heating / cooling to such a glass substrate, only the bonds of the glass molecules will be cut, There is no residual stress in the microplastic deformation region as in the case where the groove is formed by the wheel cutter described above, and then the stress is applied to hold the crack and cut.

  Therefore, by the cutting method using local heating and cooling to such a glass substrate, it is possible to suppress the occurrence of microcracks or the like on the cut surface of the glass substrate after cutting. Breaking of the glass substrate starting from is prevented.

  For example, in Patent Document 1 shown below, as shown in FIG. 8A, a cutting start groove 41 having a predetermined length is provided at the start end of a scheduled cutting line 32a of the glass substrate 32, and the wheel cutter 31 in FIG. By using the laser beam 42 and the cooling water 43 as shown in FIG. 8B to scan along the planned cutting line 32a, a crack line is formed on the glass substrate 32. A cutting method for forming and cutting 44 is disclosed.

  In this case, by forming the cutting start groove 41 in advance, the first crack in the thickness direction of the glass substrate 32 starting from the cutting start groove 41 is generated by local heating and cooling of the cutting start groove 41. It is easy to make it. Therefore, the crack line 44 is obtained by extending the first crack generated in the cutting start groove 41 portion along the planned cutting line 32a.

JP 2000-61677 A

  However, in recent years, a mother glass substrate used for a display panel such as a liquid crystal display panel has been increased in size (eighth generation: 2160 mm × 2460 mm). Therefore, the cutting termination portion of the glass substrate is caused by heating and cooling. Since thermal distortion hardly occurs, an uncut portion 45 of several millimeters as shown in FIG. 9 may occur.

  In order to prevent this, normally, the scanning speed of heating and cooling by the laser beam 42 and the cooling water 43 is reduced at the cutting end portion, but the crack line 44 is still formed on the glass substrate as shown in the figure. There is a case that the uncut portion 45 is generated without extending to the terminal portion of 42 and the glass substrate 32 cannot be completely cut.

  Accordingly, the problem to be solved by the present invention is to provide a glass substrate cutting method and a glass substrate cutting apparatus in which an uncut portion is not generated at a cutting end portion when a glass substrate is cut by heating and cooling.

  In order to solve the above problems, a glass substrate cutting device according to the present invention has a detection unit that detects a start end and a termination of a line to be cut on the surface of the glass substrate, and the cutting line detected by the detection unit is detected. Groove forming means for forming a cutting start groove at the start end and a cutting end groove at the end of the scheduled cutting line, a heating unit for locally heating the glass substrate, and a cooling unit for cooling a region heated by the heating unit By scanning the surface of the glass substrate with the heating unit and the cooling unit, a crack generated in the thickness direction of the glass substrate forms a crack line extending from the start end to the end of the scheduled cutting line And a crack line forming means

  In this case, the groove forming means and the crack line forming means are preferably provided in this order along the scanning direction. The groove forming means may be configured to include a wheel cutter. Furthermore, the heating part of the crack line forming means may be configured to irradiate the glass substrate with laser light. And the said cooling part of the said crack line formation means is good to be comprised so that a cooling water may be ejected to the said glass substrate.

  In addition, in order to solve the above-described problem, the glass substrate cutting method according to the present invention is a groove formation in which a cutting start groove is formed at the start end of a scheduled cutting line on the surface of the glass substrate and a cutting end groove is formed at the end of the scheduled cutting line. A crack line in which a crack generated in the thickness direction of the glass substrate extends from the start end to the end of the cutting planned line by locally heating and cooling the glass substrate while scanning the surface of the glass substrate And a crack line forming step for forming the gist.

  In this case, in the groove forming step, the cutting start groove is first formed at the start end of the planned cutting line, and the cutting end groove is formed at the end of the planned cutting line before the subsequent crack line step is completed. It is good to have a configuration to do.

  According to the glass substrate cutting apparatus and the glass substrate cutting method having the above-described configuration, since the cutting end groove is formed at the end of the cutting line of the glass substrate, the cutting end groove is also heated. As a result, a crack starting from this cutting end groove can be generated, and the crack line extending along the planned cutting line is connected to this crack, so that the end portion of the planned cutting line of the glass substrate is surely connected. Can be cut off. As a result, an uncut portion is not generated at the cutting end portion of the glass substrate as described in the prior art, and the glass substrate can be completely cut.

  In the glass substrate cutting apparatus having the above configuration, the groove forming means and the crack line forming means are sequentially provided from the front in the scanning direction, that is, the detection unit, the wheel cutter, the heating unit, and the cooling unit are scanned. If the configuration is provided in this order along the direction, the detection unit first detects the starting end of the cutting line on the surface of the glass substrate, and the wheel cutter forms a cutting start groove at the starting end, and then the heating unit and the cooling unit By forming a crack line extending from the crack generated in the cutting start groove part by cutting the glass substrate, the detection unit detects the end of the scheduled cutting line on the surface of the glass substrate, and the wheel cutter A cut end groove is formed at the end, and the last extending crack line is connected to a crack generated in the end cut groove portion, so that the glass substrate is completely cut easily. Preparative it is, it can be a glass substrate cutting apparatus in a simple structure.

  Below, one embodiment of a glass substrate cutting device and a glass substrate cutting method concerning the present invention is described with reference to drawings. FIG. 1 is a diagram illustrating a schematic configuration of a glass substrate cutting apparatus, and FIGS. 2 and 3 are diagrams sequentially illustrating a procedure for cutting a glass substrate using the glass substrate cutting apparatus.

  As shown in the figure, the glass substrate cutting apparatus 1 includes a substrate stage 2 on which the glass substrate 20 is placed, and a cutting line 20a of the glass substrate 20 as shown in FIGS. 2 (a) and 3 (a). A groove forming unit 3 for forming a cutting start groove 21 and a cutting end groove 23 at both ends of the substrate, a crack line forming unit 4 for forming a crack line 22 to cut the glass substrate 20, and a control for controlling the operation of these units. Part 5.

  The glass substrate 20 is a plate made of a brittle material having a quadrangular shape. For example, a non-alkali glass substrate having a thickness of 0.7 mm used for a liquid crystal display panel is used. The substrate stage 2 can suck and hold the placed glass substrate 20, and in this case, the substrate stage 2 sucks the back surface of the glass substrate 20 so as to remove a portion that is cut and removed.

  The substrate stage 2 can be moved in the direction in which the planned cutting line 20a extends (X direction) and in the direction perpendicular to the planned cutting line 20a (Y direction) by the drive unit 6, and the glass substrate 20 and each unit 3, It is possible to move in the vertical direction (Z direction) so that the distance to 4 can be adjusted. When cutting the glass substrate 20, the drive unit 6 moves the substrate stage 2 in the X direction at an optimum speed for cutting the glass substrate 20.

  The groove forming unit 3 is fixed to an apparatus frame (not shown) at a position above the substrate stage 2, and includes a detection unit 7 on the front side and a wheel cutter 8 on the rear side. The detection unit 7 detects the left and right ends of the glass substrate 20 moved in the X direction (scanning direction) by the substrate stage 2, and outputs the detection signal to the control unit 5. As the detection unit 7, a distance measuring sensor, a magnetic sensor, or the like is applied.

  The wheel cutter 8 is formed from a material such as a single crystal or sintered body of artificial diamond, and the outer peripheral edge of the wheel is tapered. In this case, the wheel cutter 8 is fixed to the lower end of the elevating unit 9, and is provided so that it can be moved up and down by the elevating unit 9.

  As shown in FIG. 2A and FIG. 3A, the wheel cutter 8 is lifted by the lifting unit 9 at the left and right start and end of the planned cutting line 20 a of the glass substrate 20 at the cutting start groove 21 and the cutting end groove 23. The control unit 5 controls the ascending / descending operation so as to move down to a predetermined position and wait.

  In this case, the cutting start groove 21 formed by the wheel cutter 8 is formed at the left end portion of the surface of the glass substrate 20 like a streak of a length of about 10 mm at the start end of the cutting scheduled line 20a. Further, the cutting end groove 23 is formed at the right end portion of the surface of the glass substrate 20 like a streak-like scratch having a length of about 10 mm at the end of the planned cutting line 20a.

  Similarly to the groove forming unit 3 described above, the crack line forming unit 4 is fixed to an apparatus frame (not shown) at a position above the substrate stage 2, and includes a heating unit 10 at the front and a cooling unit 11 at the rear.

  By scanning the crack line forming unit 4 including the heating unit 10 and the cooling unit 11 in the X direction along the planned cutting line 20a on the surface of the glass substrate 20, the glass substrate 20 is heated and immediately cooled. The crack line 22 which cuts the glass substrate 20 is formed by extending a vertical crack extending from the front surface to the back surface of the glass substrate 20 along the planned cutting line 20a.

The heating unit 10 generates a laser having a wavelength with excellent absorption characteristics with respect to the glass substrate 20 based on a control signal from the control unit 5, and converts the laser light 13 collected through the condenser lens 12 into glass. The surface of the substrate 20 is irradiated and heated. As such a laser beam 13, a CO ₂ laser beam or a YAG laser beam is used. In this case, the focal position of the laser beam 13 when irradiating the glass substrate 20 is set at a position slightly below the back surface of the glass substrate 20.

  Based on a control signal from the control unit 5, the cooling unit 11 ejects cooling water 14 such as room temperature water onto the surface of the glass substrate 20, and cools the glass substrate 20 heated by being irradiated with the laser beam 13. To do. A spray nozzle is provided at the tip of the cooling unit 11, and the cooling water 14 is jetted to the glass substrate 20 in the form of a mist.

  In this case, the region immediately after passing the region irradiated with the laser beam 13 of the glass substrate 20 is actively cooled by the cooling water 14, thereby causing thermal distortion (thermal expansion and contraction) in the glass substrate 20. ) And a crack from the front surface of the glass substrate 20 to the back surface can be generated by the stress due to the thermal strain.

  What this crack extended along the scheduled cutting line 20a becomes the crack line 22, and the glass substrate 20 is divided into two from this crack line 22.

  Next, a procedure for cutting the glass substrate 20 using such a glass substrate cutting apparatus 1 will be described with reference to FIGS.

  First, the detection unit 7 of the groove forming unit 3 detects the left end of the glass substrate 20, that is, the start end of the scheduled cutting line 20a. The detection unit 7 outputs a detection signal to the control unit 5. At this time, the wheel cutter 8 of the groove forming unit 3 stands by at an upper position.

  Then, the control unit 5 lowers the wheel cutter 8 based on the output signal from the detection unit 7. As shown in FIG. 2A, the lowered wheel cutter 8 forms a cutting start groove 21 having a predetermined length at the left end portion of the glass substrate 20, and then rises and waits at a predetermined position.

  Next, the laser beam 13 of the heating unit 10 of the crack line forming unit 4 is irradiated from the rear end to the front end of the cutting start groove 21, and this portion is rapidly heated. Immediately after that, the cooling water 14 of the cooling part 10 of the crack line forming unit 4 is similarly ejected from the rear end to the front end of the cutting start groove 21, and this part is rapidly cooled.

  At this time, the first crack in the thickness direction of the glass substrate 20 starting from the cutting start groove 21 is generated by local heating and cooling of the cutting start groove 21.

  And after that, by adding heating and cooling to the glass substrate 20 along the scheduled cutting line 20a by the heating unit 10 and the cooling unit 11 of the crack line forming unit 4, as shown in FIG. The crack line 22 is formed so as to extend from the first crack generated in the groove 41 portion along the planned cutting line 20a.

  Next, when such a crack line 22 is formed so as to extend along the planned cutting line 20a, when the groove forming unit 3 approaches the end of the planned cutting line 20a, that is, near the right end of the glass substrate 20, a groove is formed. The detection unit 7 of the unit 3 detects the right end portion of the glass substrate 20.

  Then, the control unit 5 lowers the wheel cutter 8 based on the output signal from the detection unit 7. As shown in FIG. 3A, the lowered wheel cutter 8 forms a cutting end groove 23 having a predetermined length at the left end portion of the glass substrate 20.

  Thereafter, when the crack line forming unit 4 forms the crack line 22 and reaches the cutting end groove 21, the thickness of the glass substrate 20 starting from the cutting end groove 23 by local heating and cooling to the cutting end groove 23. The last crack in the direction is generated, and this is connected to the crack line 22 extending to the rear end of the cutting end groove 23, so that the crack line 22 cuts the glass substrate 20 as shown in FIG. It is formed on all the planned lines 20a. Thereby, the glass substrate 20 is divided into two parts as shown in FIG.

  According to the glass substrate cutting method described above, since the cutting end groove 23 is also formed at the end of the scheduled cutting line 20a of the glass substrate 20, this cutting end groove 23 is also heated and cooled, thereby A crack starting from the cutting end groove 23 can be generated, and the crack line 22 extending along the cutting planned line 20a is connected to the crack, so that the cutting line 20a of the glass substrate 20 is surely cut. The end portion can be cut.

  As a result, an uncut portion is not generated at the cutting end portion of the glass substrate as described in the prior art, and the glass substrate can be completely cut.

  Moreover, since the glass substrate cutting device 1 mentioned above is the structure by which the groove | channel formation unit 3 and the crack line formation unit 4 are provided in this order along the scanning direction, it is possible to make an apparatus a simple structure.

  That is, the glass substrate cutting apparatus 1 has a configuration in which the detection unit 7, the wheel cutter 8, the heating unit 10, and the cooling unit 11 are provided in this order along the scanning direction above the substrate stage 2. The detection unit 7 detects the starting end of the scheduled cutting line 20a on the surface of the glass substrate 20, and the wheel cutter 8 forms the cutting start groove 21 at the starting end, and then the heating unit 10 and the cooling unit 11 form the cutting start groove 21 portion. While the crack line 22 extending from the generated crack is formed and the glass substrate 20 is cut, the detection unit 7 detects the end of the cutting line 20a on the surface of the glass substrate 20 again, and the wheel cutter 8 is at the end. The cutting end groove 23 is formed, and the glass substrate 20 is completely and simply connected to the crack line 22 extending lastly in the cutting end groove 21 portion. It is possible to cross, a glass substrate cutting apparatus 1 can be a simple structure.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to such embodiment at all, Of course, in the range which does not deviate from the summary of this invention, it can implement in a various aspect.

  For example, the configuration in which each unit is separated such as the groove forming unit 3 including the detection unit 7 and the wheel cutter 8 and the crack line forming unit 4 including the heating unit 10 and the cooling unit 11 has been described. However, the present invention is not limited to the above-described embodiment.

  Moreover, although the structure which moves the glass substrate 20 with respect to the groove | channel formation unit 3 and the crack line formation unit 4 with the substrate stage 2 was demonstrated, the groove formation unit 3 and the crack line formation unit 4 are moved with respect to the glass substrate 20. It may be configured.

It is the figure which showed schematic structure of the glass substrate cutting device which concerns on one Embodiment of this invention. It is the figure which showed the procedure which cut | disconnects a glass substrate using the glass substrate cutting device of FIG. It is the figure which showed the next procedure of the procedure which cut | disconnects the glass substrate of FIG. It is the figure which showed the glass substrate cut | disconnected using the glass substrate of FIG. (A) is the figure which showed the procedure which cut | disconnects the mother glass substrates used conventionally and cuts from bonding, and manufactures each liquid crystal display panel, (b) cuts the mother glass substrate used conventionally conventionally It is the figure which showed the procedure which manufactures a liquid crystal display panel by bonding together after that. (A) is the figure which showed the method of cut | disconnecting a glass substrate using a wheel cutter, (b) is the figure which showed the state of the cut surface of the glass substrate cut | disconnected by the cutting method of (a). (A) is the figure which showed the state which the crack produced from the micro clock etc. which generate | occur | produced in the cut surface of the glass substrate, (b) The figure which showed the method of chamfering the cut surface of the glass substrate used conventionally It is. (A) is the figure which showed the state which formed the groove | channel previously in the edge part of a glass substrate before the cutting | disconnection by the cutting method of (b), (b) is the cutting method by the heating and cooling to the glass substrate conventionally used FIG. It is the figure which showed the state which the uncut part generate | occur | produced in the glass substrate cut | disconnected by the cutting method of FIG.8 (b).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Glass substrate cutting device 2 Substrate stage 3 Groove formation unit 4 Crack line formation unit 5 Control part 6 Drive part 7 Detection part 8 Wheel cutter 9 Lifting part 10 Heating part 11 Cooling part 12 Condensing lens 13 Laser beam
14 Cooling water 20 Glass substrate 20a Scheduled cutting line 21 Cutting start groove 22 Crack line 23 Cutting end groove

Claims (7)

  A detection unit for detecting a start end and an end of a planned cutting line on the surface of the glass substrate, and a cutting start groove and a cutting end groove at the end of the planned cutting line detected by the detection unit; A groove forming means for forming, a heating unit for locally heating the glass substrate, and a cooling unit for cooling a region heated by the heating unit, and the surface of the glass substrate is cooled with the heating unit and the cooling unit. A glass substrate cutting comprising: a crack line forming means for forming a crack line in which a crack generated in a thickness direction of the glass substrate extends from a starting end to an end of the scheduled cutting line by scanning with a portion apparatus.   The glass substrate cutting device according to claim 1, wherein the groove forming means and the crack line forming means are provided in this order along the scanning direction.   The said groove | channel formation means is equipped with the wheel cutter, The glass substrate cutting device of Claim 1 or 2 characterized by the above-mentioned.   The glass substrate cutting apparatus according to any one of claims 1 to 3, wherein the heating unit of the crack line forming unit is configured to irradiate the glass substrate with laser light.   The said cooling part of the said crack line formation means is comprised so that a cooling water may be ejected to the said glass substrate, The glass substrate cutting device as described in any one of Claim 1 to 4 characterized by the above-mentioned.   A groove forming step of forming a cutting start groove at the start end of the planned cutting line on the surface of the glass substrate and a cutting end groove at the end of the planned cutting line, and locally heating the glass substrate while scanning the surface of the glass substrate And a glass substrate cutting characterized by comprising a crack line forming step of forming a crack line extending from the start end to the end of the planned cutting line by causing the crack generated in the thickness direction of the glass substrate by cooling. Method.   In the groove forming step, a cutting start groove is first formed at the start end of the planned cutting line, and a cutting end groove is formed at the end of the planned cutting line before the subsequent crack line step is completed. The glass substrate cutting method according to claim 6, wherein the glass substrate is cut.

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