JP2010113338A - Method for manufacturing glass substrate for fpd - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for efficiently manufacturing a glass substrate for an FPD, of which the strength is not deteriorated even when the thickness is reduced by resolving shortcomings of a laser cutting method. <P>SOLUTION: Glass substrates divided for respective display cell regions are manufactured by conducting: a preliminary step ST1 of forming a first scribe line 5a to partition the display cell region on a surface of a first glass substrate G1; a scanning step ST3 of scanning a laser beam along the first scribe line 5a; and a cutting step ST4 of cutting a laminate glass substrate by forming a second scribe line 5b on a surface of a second glass substrate G2 corresponding to the first scribe line 5a, in this order, in relation to the laminate glass substrate 1 with a plurality of display cell regions disposed between the first glass substrate G1 and the second glass substrate G2. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing an FPD glass substrate, and more particularly to a method for manufacturing a laminated glass substrate in which a plurality of display cell regions are provided between a pair of glass substrates.

  A flat panel display (referred to as FPD in this specification) is a term that is contrasted with a display device having a bulge, such as a cathode ray tube of a CRT display, has a small depth, saves space, and has no bulge in the display panel. There is a big feature in the point, and a liquid crystal display, a plasma display, an organic EL display, etc. are put into practical use. Among FPDs, in particular, liquid crystal displays are widely used not only as television receivers but also as display devices for mobile phones and computer equipment.

  By the way, based on the demand for lighter and thinner liquid crystal displays, recently, a method of chemically polishing a laminated glass substrate constituting a liquid crystal display to the limit is suitably employed. Specifically, the first and second glass substrates provided with a plurality of display panel regions are bonded together, and the outer periphery of the bonded glass substrate is sealed and immersed in an aqueous solution containing hydrofluoric acid to perform chemical polishing. And thinned. In the fifth generation, the laminated glass substrate is, for example, 1100 mm long × 1250 mm wide, and in the sixth generation, for example, 1500 mm × 1850 mm.

  According to this chemical polishing method, not only can a plurality of display panels be manufactured together, but also the processing speed is higher than that of mechanical polishing, and thus there is an advantage that the productivity is excellent. Moreover, according to said chemical polishing method, since a laminated glass substrate can be thinned to the limit, it can respond to the further request | requirement of thickness reduction and weight reduction of a display panel.

  In this way, the laminated glass substrate thinned to the limit is then divided into individual display panels by physical and / or chemical methods. As a suitable cutting method, a scribe line formed by using a wheel cutter made of diamond or cemented carbide is polished in the depth direction in accordance with the chemical polishing of the glass substrate, and finally, glass along the scribe line. A method of cleaving a substrate is known (for example, Patent Document 1).

  According to the invention described in Patent Document 1, the etching liquid is brought into contact with the laminated glass substrate, and the glass cracks generated during the scribe line formation are removed. Sufficient strength can be exhibited.

JP 2004-307318 A JP 2008-162824 A

  However, if the amount of etching is increased in order to make the laminated glass substrate extremely thin, the scribe line originally formed in a V shape is completely smoothed in the process of deep chemical polishing by etching. And subsequent cutting and separation may be difficult. If the polishing amount is too small, cracks generated during the formation of the scribe line remain, and the strength of the divided glass substrate is deteriorated.

  By the way, instead of using a cutter blade, a cutting and separating method using laser light (hereinafter referred to as laser cutting method) is also known (for example, Patent Document 2).

  However, in general, in the laser cutting method, it is necessary to physically provide the start scratch ST of the scanning line of the laser beam, and in particular, the method of cutting the bonded glass substrate is inferior in workability. That is, in order to divide the laminated glass substrate, it is necessary to scan the laser beam not only on the front surface but also on the back surface, and moreover, it is necessary and troublesome to provide each start scratch on the scanning line. is there. Referring to FIG. 5, in the laser cutting method, the cutting line cannot be extended beyond the already formed cutting line CL unless there is another starting flaw. After providing a large number of starting scratches ST (FIG. 5A), the front and back surfaces of the laminated glass substrate were scanned with laser light and cut into strip-shaped cut pieces (FIGS. 5B and 5C). )), There is a complication that it is necessary to repeat the same operation for each piece.

  In the laser cutting method, the conditions for the flatness of the thickness of the glass substrate are strict. For example, the positional variation of a glass substrate having a thickness of about 0.5 mm needs to be suppressed to less than 20 μm. However, for example, when a laminated glass substrate having an area of about 1 m × 1 m is thinned to 0.5 mm or less, it is very difficult to meet the above requirements. Will increase significantly.

  Furthermore, in the laser cutting method, an angle close to a right angle is generated on the cut surface of the glass substrate, and in the subsequent work, the corner of the glass substrate comes into contact with other members and causes cracks. There is also.

  The present invention has been made in view of the above-described problems, and provides a manufacturing method that can efficiently manufacture a glass substrate for FPD that does not deteriorate in strength even if it is thinned by eliminating the disadvantages of the laser cutting method. For the purpose.

  In order to achieve the above object, a method for manufacturing a glass substrate for FPD according to claim 1 is the above-described laminated glass substrate provided with a plurality of display cell regions between a first glass substrate and a second glass substrate. Corresponding to the first scribe line, a preliminary step of forming a first scribe line for partitioning the display cell region on the surface of the first glass substrate, a scanning step of scanning a laser beam along the first scribe line Then, a cutting step of forming a second scribe line on the surface of the second glass substrate to divide the bonded glass substrate is performed in this order, and the glass is separated for each display cell region. Manufactures substrates.

  Moreover, the manufacturing method of the glass substrate for FPD which concerns on Claim 2 is a said 1st glass substrate and the said about the bonding glass substrate which provided the several display cell area | region between the 1st glass substrate and the 2nd glass substrate. A preliminary process for forming first and second scribe lines at corresponding positions that define the display cell region on each surface of the second glass substrate, along the first scribe lines formed on the first glass substrate. A scanning step of scanning the laser beam and a cutting step of dividing the bonded glass substrate along the first and second scribe lines are performed in this order, and are separated for each display cell region. Manufacturing glass substrates.

  Moreover, the manufacturing method of the glass substrate for FPD which concerns on Claim 3 is the said 1st glass substrate and the said about the bonding glass substrate which provided the several display cell area | region between the 1st glass substrate and the 2nd glass substrate. A preliminary process for forming first and second scribe lines at corresponding positions that define the display cell region on each surface of the second glass substrate, along the first scribe lines formed on the first glass substrate. The glass separated by each display cell region is scanned in this order by scanning the laser beam and dividing the bonded glass substrate along the first and second scribe lines. Manufactures substrates.

  In each of the above inventions, the scribe line in the preliminary process may be formed by scanning a laser beam, but preferably it should be formed mechanically using a cutter blade. In the case of using a cutter blade, the conditions for the flatness of the thickness of the glass substrate are not strictly required as in the case of using laser light. In addition to the formation of the scribe line, an extra work for providing a laser scanning start flaw is also unnecessary. The scribing line is preferably formed in a straight line, but a curved scribing line is not excluded. Further, the scribe line is preferably a continuous line, but may be a discrete line formed in a dotted shape.

  In the above invention, since the scribe line can be formed vertically and horizontally in the preliminary process, the cutting line can be extended beyond the already formed cutting line in the scanning process. In addition, the crack which arose at the time of formation of the scribe line of a preliminary | backup process can be lose | disappeared in the process in which a glass surface melt | dissolves and changes in a subsequent scanning process.

  However, preferably, a polishing process should be provided between the preliminary process and the scanning process, and a chemical polishing liquid containing hydrofluoric acid should be brought into contact with the scribe line. When such a configuration is adopted, each glass substrate after being cut and separated as a result of the V-shaped cut line (scribe line) being smoothed in the process of etching the scribe line in the depth direction and the width direction. Since no corners are formed on the end face, no subsequent cracks are generated.

  Here, in the polishing process, it is preferable to immerse the bonded glass substrate in a chemical polishing liquid. When such a configuration is adopted, the bonded glass substrate can be thinned easily during the process of etching the scribe line. As a result, an extremely thin display panel can be manufactured.

  Since the etched scribe line is only a preliminary cutting line in the subsequent scanning process, even when the etching amount is increased and the surface is smoothed to a considerable level, the manufacturing method of Patent Document 1 is adopted. There will be no adverse effects at the time of splitting.

  In the invention which concerns on Claim 1, it is suitable to form a scribe line mechanically using a cutter blade in a parting process. However, the use of laser light is not particularly prohibited.

  On the other hand, the invention according to claim 2 preferably employs a method of scanning the laser beam along the second scribe line or mechanically pressurizing along the second scribe line in the dividing step.

  Further, it is preferable that the first glass substrate is not exposed to the user in the flat panel display, and the second glass substrate is exposed to the user. When such a configuration is adopted, at least the peripheral line on the outer surface side of the first glass substrate that is not exposed to the user is smooth, and the cracks of the glass generated when the scribe line is formed are completely removed. Therefore, when using the completed flat panel display, even if pressure is applied from the second glass substrate G2 exposed to the user toward the first glass substrate G1 (see FIG. 1B), the flat panel display is difficult to break. . That is, since the peripheral line L1 on the outer surface side of the first glass substrate that is most elongated under pressure is smooth, there is no starting point when the glass breaks, and excellent fracture resistance is exhibited.

  The glass used in the present invention is not particularly limited, but if it is classified into soda-lime glass, borosilicate glass, aluminosilicate glass, and quartz glass, soda-lime glass is an elution of alkali metal during the production of FPD. For example, borosilicate glass and aluminosilicate glass are preferably used because quartz glass is expensive.

  Here, borosilicate glass is a glass containing boron oxide, and has an advantage of better heat resistance than soda lime glass. Borosilicate glass is a concept that includes barium borosilicate glass that further contains barium oxide in addition to boron oxide.

  On the other hand, aluminosilicate glass is a silicate glass containing 18 to 28% by weight of aluminum oxide, and has better heat resistance, thermal stability, and chemical durability than borosilicate glass. More suitable. The aluminosilicate glass also includes an aluminoborosilicate glass containing boron oxide and aluminum oxide.

  In addition, when glass is classified according to alkali components, alkali-free glass is preferably used. Here, the alkali-free glass means a silicate glass having an alkali metal content of 1% or less, and is a concept including borosilicate glass and aluminosilicate glass.

  As the optimum glass, an aluminosilicate glass having a SiO2 content of 55 to 60% by weight, an Al2O3 content of 16 to 18% by weight, and a B2O3 content of about 7 to 10% by weight is used.

  According to the above-described present invention, it is possible to efficiently manufacture a glass substrate for FPD which eliminates the disadvantages of the laser cutting method and does not have inferior strength even if it is thinned.

It is a process flow figure explaining a manufacturing method of a pasting glass substrate of a 1st embodiment. It is a figure for demonstrating each process of FIG. It is a process flow figure explaining a manufacturing method of a pasting glass substrate of a 2nd embodiment. It is a figure for demonstrating each process of FIG. It is drawing explaining the problem of a prior art.

  Hereinafter, the manufacturing method of the glass substrate for FPD which concerns on this invention based on embodiment is demonstrated. FIG. 1A is a process flow diagram showing the manufacturing method of the first embodiment. Here, a laminated glass substrate provided with a plurality of display cell regions between the first glass substrate G1 and the second glass substrate G2 is chemically polished to a target thickness T to be thinned, and then used for individual display panels. The procedure until the glass substrate is divided is described.

  In this manufacturing method, after the FPD is completed, a preliminary step (ST1) for forming a scribe line 5a serving as a preliminary cutting line on the surface of the first glass substrate G1 that is not exposed to the user, and a laminated glass substrate 1 having a plate thickness T + δ A polishing step (ST2) for thinning to a plate thickness T by immersion in an etching solution, a scanning step (ST3) for changing the glass substrate by scanning a laser beam along the scribe line 5a, and a user after completion of the FPD And a cutting step (ST4) in which a scribe line 5b serving as a cutting line is formed on the surface of the second glass substrate G1 exposed to divide each display panel.

  Hereinafter, a description will be given with reference to FIGS. 3 (a) to 3 (e). As shown in FIG. 3A, in the preliminary step ST1, scribe lines 5a are formed vertically and horizontally on the surface of the first glass substrate G1 for the laminated glass substrate 1 having a thickness T + δ slightly thicker than the final plate thickness T. The scribe line 5a is made of a disk-shaped hole cutter 4 made of diamond or cemented carbide and having a pointed peripheral surface.

  When the final thickness T of the laminated glass substrate 1 is, for example, 0.32 mm, the laminated glass substrate 1 having a thickness of about 1 mm precedes the preliminary step (ST1) in the initial stage. For example, the thickness is reduced to about 0.38 mm. Therefore, in such an example, a scribe line is formed on the laminated glass substrate 1 having a plate thickness of 0.38 mm, and the etching amount in the subsequent polishing step is 60 μm (30 μm on one side). Become.

  However, in the present invention, even if the V-shaped bottom surface of the scribe line 5a is rounded in the subsequent polishing step, there is no particular problem, so the etching amount in the polishing step is increased to about 100 μm to 200 μm. be able to. Increasing the etching amount means that a scribe line is provided on the laminated glass substrate 1 at a stage where the plate thickness is thicker (for example, about 0.5 mm). 1 is easy to handle and the workability is improved.

  By the way, the 1st glass substrate G1 in which a scribe line is formed is not exposed to a user after FPD completion. That is, a thin film transistor and a transparent electrode are formed on the surface of the first glass substrate G1 facing the second glass substrate G2, and an alignment film is further laminated. On the other hand, on the surface of the second glass substrate G2 facing the first glass substrate G1, a color filter is formed by being divided into a black matrix, and an overcoat, a transparent electrode, and an alignment film are sequentially laminated. The glass substrates G1 and G2 are bonded together with a spacer, a partition resin 3 and an outer peripheral resin interposed between the glass substrates G1 and G2.

  Since the display cell regions are each partitioned by the partition resin 3, the scribe line 5 a is formed at a substantially central position between the adjacent partition resins 3 and 3. In addition, a polarizing plate is affixed on the outer surface of the laminated glass substrate 1 after the cutting process (ST4) of this embodiment.

  The bonded glass substrate on which the scribe line 5a is formed is immersed in a chemical polishing solution, the bonded glass substrate 1 is thinned, and the scribe line 5a is smoothened and deepened (ST2). The chemical polishing liquid is not particularly limited, but a polishing liquid containing hydrofluoric acid less than 10% by weight of hydrofluoric acid is suitable.

  The polishing amount is not particularly limited, but the upper limit of the polishing amount is about 100 to 200 μm for the entire laminated glass substrate in order to leave the scribe line 5a significantly. As the etching amount in the plate thickness direction increases, the scribe line 5a tends to be flattened, and the deepest distal end portion of the scribe line originally formed in a substantially V-shaped cross section is rounded, and both sides of the proximal end are formed. The side surface of the can also be rounded into a substantially arc shape. Therefore, the end face of each glass substrate after cutting and separation does not cause cracks only by contacting something.

  When the polishing step (ST2) is completed, the bonded glass substrate 1 is washed and dried, and then the laser beam is scanned along the scribe line 5a to alter the glass surface (ST3). In this embodiment, since the scribe line is formed vertically and horizontally, laser irradiation can be started without providing a scanning start flaw. Further, in this scanning step, the cutting line can be extended beyond the already formed cutting line, so that the cutting line can be formed at a stretch corresponding to the display cell region.

  In addition, when the amount of polishing in the polishing step is small, cracks generated during the formation of the scribe line may remain, but harmful cracks can be eliminated in the process of melting and changing the glass surface. . On the other hand, when the polishing amount in the polishing process is large, the deepest end of the scribe line is rounded, but there is no particular hindrance to glass alteration due to laser scanning. Further, even if there is some variation in the plate thickness T, there is no particular problem. In addition, if it is a laminated glass substrate which has an area of about 1 m × 1 m, the thickness variation after the polishing process is preferably controlled to be less than 40 μm.

  If the laser irradiation process about the surface of the 1st glass substrate G1 is completed, the bonding glass substrate 1 will be turned upside down, and the scribe line of the 1st glass substrate G1 in the 2nd glass substrate G2 will be used using the cutter blade 4. A scribe line is provided at a position corresponding to 5a to divide the glass substrate (ST4).

  In addition, by pressing the cutter blade 4, the second glass substrate G2 of the laminated glass substrate 1 that has been thinned is substantially cleaved. However, in order to increase the final mechanical strength, even if the glass substrate is divided by irradiating a laser beam along the scribe line after providing a shallow scribe line that does not cut the second glass substrate. good.

  FIG. 3 is a process flow diagram showing the manufacturing method of the second embodiment. In this manufacturing method, a preliminary step (ST11) for forming scribe lines 5a and 5b, which are preliminary cutting lines, on the surfaces of the first glass substrate G1 and the second glass substrate G2, and the laminated glass substrate 1 having a thickness T + δ are etched. A polishing step (ST12) in which the glass substrate is thinned by immersion in the liquid, a scanning step (ST13) in which the laser beam is scanned along the scribe line 5a of the first glass substrate G1 to alter the glass substrate, and cutting And a cutting step (ST4) for dividing each display panel along the scribe lines 5a and 5b.

  The operation content of each process of steps ST11 to ST13 is substantially the same as the operation content of steps ST1 to ST3 of the first embodiment. However, in the cutting process ST14, a load is applied along the scribe line 5b of the second glass substrate G2. Alternatively, the laminated glass substrate 1 is cut by scanning the laser beam along the scribe line 5b.

  Here, when a method of dividing the laminated glass substrate 1 by applying a load along the scribe line 5b is taken, the polishing amount in the polishing step is set to 100 μm in order to avoid an unnecessarily smooth surface of the scribe line 5b. Should be suppressed to less than.

  On the other hand, when the method of dividing the laminated glass substrate 1 by scanning the laser beam along the scribe line 5b is adopted, the above-described limitation of the polishing amount is unnecessary, and the upper limit of the polishing amount is the bonded glass substrate. The total is about 100 to 200 μm.

  By the way, in FIG. 3, although the cutting process is provided separately from the scanning process, the laminated glass substrate is divided at a stretch along the scrub lines 5a and 5b of the first and second glass substrates by laser light irradiation. You can also.

  Although the three embodiments have been specifically described above, the present invention is not limited to the above embodiments. For example, in FIGS. 1-4, although the laminated glass substrate for liquid crystal displays was demonstrated, if a pair of glass substrates are pasted together, it is a laminated glass substrate for liquid crystal displays. Not a question.

Claims (11)

About the bonded glass substrate which provided the some display cell area | region between the 1st glass substrate and the 2nd glass substrate, the 1st scribe line which divides the said display cell area | region is formed in the surface of said 1st glass substrate. A preliminary process;
A scanning step of scanning the laser beam along the first scribe line;
Corresponding to the first scribe line, on the surface of the second glass substrate, forming a second scribe line and cutting the bonded glass substrate,
Are performed in this order, and the manufacturing method of the glass substrate for flat panel displays which manufactures the glass substrate isolate | separated for every said display cell area | region. About the bonded glass substrate which provided the some display cell area | region between the 1st glass substrate and the 2nd glass substrate, the said display cell area | region in each surface of said 1st glass substrate and said 2nd glass substrate is divided. A preliminary step of forming first and second scribe lines at corresponding positions;
A scanning step of scanning a laser beam along a first scribe line formed on the first glass substrate;
A cutting step of dividing the laminated glass substrate along the first and second scribe lines;
Are performed in this order, and the manufacturing method of the glass substrate for flat panel displays which manufactures the glass substrate isolate | separated for every said display cell area | region. About the bonded glass substrate which provided the some display cell area | region between the 1st glass substrate and the 2nd glass substrate, the said display cell area | region in each surface of said 1st glass substrate and said 2nd glass substrate is divided. A preliminary step of forming first and second scribe lines at corresponding positions;
A scanning step of scanning a laser beam along a first scribe line formed on the first glass substrate, and dividing the bonded glass substrate along the first and second scribe lines;
Are performed in this order, and the manufacturing method of the glass substrate for flat panel displays which manufactures the glass substrate isolate | separated for every said display cell area | region.   The manufacturing method in any one of Claims 1-3 which provided the grinding | polishing process which contacts the chemical polishing liquid containing a hydrofluoric acid to a said 1st scribe line between the said preliminary | backup process and the said scanning process.   The manufacturing method according to claim 4, wherein in the polishing step, the bonded glass substrate is immersed in a chemical polishing liquid.   The manufacturing method according to claim 1, wherein in the preliminary step, the scribe line is mechanically formed using a cutter blade.   The manufacturing method according to claim 1, wherein in the dividing step, the scribe line is mechanically formed using a cutter blade.   The manufacturing method according to claim 2, wherein in the dividing step, laser light is scanned along the second scribe line.   The manufacturing method according to claim 2, wherein a load is applied along the second scribe line in the dividing step.   The manufacturing method according to claim 1, wherein the first glass substrate is not exposed to a user in a flat panel display, and the second glass substrate is exposed to the user.   The manufacturing method of the flat panel display which goes through the manufacturing process in any one of Claims 1-10.

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