WO2018020531A1 - Polishing method and polishing device for glass substrate - Google Patents

Abstract

[Problem] To provide a polishing method and a polishing device for a glass substrate, with which chemical polishing of a glass substrate surface can be performed so as to form the glass substrate into a uniform thin film, tool marks can be suppressed, risk of damage can be reduced, and high polishing efficiency can be achieved. [Solution] This polishing method for a glass substrate is for uniformly polishing the surface of a glass substrate to be used for a liquid crystal display or organic EL display and includes: an arranging step of arranging and securing a vertically-hung glass substrate; a chemical polishing step of continuously spraying and applying a chemical polishing solution on both sides of the glass substrate from a plurality of spray nozzles; and a washing step of washing the melt-polished glass substrate. In the chemical polishing step, to prevent unevenness from occurring and remaining in spray application of the chemical polishing solution due to dripping, the spray nozzles on the upper edge side of the glass substrate are disposed such that the vertical spacing or horizontal spacing therebetween is narrower than on the lower edge side of the glass substrate.

Description

Glass substrate polishing method and polishing apparatus

The present invention relates to a polishing apparatus for polishing and ultra-thinning a glass substrate. In particular, the surface of the glass substrate used for a liquid crystal display or an organic EL display is chemically polished until the glass substrate becomes thin, and the polishing efficiency is improved. The present invention relates to a polishing method and a polishing apparatus for a glass substrate for increasing the height.

Conventionally, many techniques for polishing the surface of a glass substrate to make the glass substrate ultra thin have been developed and used. Generally, polishing techniques include a method of physically polishing an object to be polished by a polishing machine, a method of electrochemically polishing an object to be polished using electricity, and a polishing using a chemical reaction by a chemical substance. There are methods.

Of these, chemical polishing is a method of polishing by using a chemical substance to dissolve the surface of the object to be polished. The object to be processed is placed in a solution tank filled with a hydrofluoric acid solution and immersed in the solution. It is often done to dissolve the surface. During dissolution, bubbling (a method of circulating a solution by applying bubbles to the object to be polished) is taken so that the surface of the object to be polished is uniformly polished. At present, chemical polishing is widely used as a method for polishing glass substrates such as liquid crystal displays and organic EL displays, and thin and light liquid crystal displays and glass substrates for organic EL displays can be manufactured by chemical polishing. It has become.

By the way, at present, liquid crystal displays are widely used as displays used in TVs and personal computers, and high-quality, high-speed, large-capacity, thin-film and light-weight are being achieved. In addition, technologies such as tablet terminals and smartphones have also advanced, and it is required to produce and deliver thin and light liquid crystal display components as displays used for these. In response to such market demands, the current situation is that liquid crystal displays are required to be made thinner.

In addition, the uniformity of the thickness of the display substrate after chemical polishing is required to be uniform in the region of the end of the substrate, and a narrow frame of the display product is also required.

In response to such demands, the chemical polishing technique using bubbling employs a batch processing method in which a plurality of substrates are simultaneously polished, and a mark of a jig for holding the substrate is a region at the end of the substrate. Therefore, there is a problem that it cannot be said that it can sufficiently cope with the demand for a narrow frame. That is, in the case of the batch processing method, in order to immerse a large number of sheets simultaneously in the polishing liquid, it is necessary to increase the speed or to stir the polishing liquid (bubbling process) in order to suppress the variation in the polishing amount depending on the place to be immersed, Although it is necessary to hold the substrate firmly so as not to be displaced or cracked, a situation has arisen in which the thickness of the end portion is not uniform due to the formation of jig marks by the jig. On the other hand, if the number of jigs that hold down the substrate is reduced to reduce the above-mentioned jig traces, or if the holding strength is weakened, the substrate is liable to shift (groove misalignment), cracks, or chipping during the polishing process. The problem was derived at the same time.

As a technique for solving such problems, there is a technique disclosed in JP2013-252984A. Here, a plurality of transport rollers configured to transport the glass substrate in the horizontal direction, and a processing chamber configured to perform a chemical polishing process on the glass substrate transported by the plurality of transport rollers, The processing chamber has at least a processing tank and a recovery tank, and the processing tank is configured such that the chemical polishing liquid overflows at a position higher than the plurality of transport rollers, and the recovery tank is a chemical that overflows from the processing tank. Techniques relating to chemical polishing configured to recover a polishing liquid are disclosed.

According to this technique, it is possible to perform chemical polishing (etching) by spraying a chemical polishing liquid in a shower form from the upper and lower surfaces of the glass substrate while conveying the glass substrate in the horizontal direction. However, in order to arrange the substrate horizontally, it is sufficient to supply the polishing liquid in a paddle form on the upper surface side of the substrate, whereas the lower surface side is placed on the substrate. Since the sprayed polishing liquid is immediately dropped by gravity, there is a problem in that the supply of the polishing liquid that can sufficiently contribute to the chemical reaction of polishing is reduced with respect to the upper surface side. Moreover, since rollers, shafts, and the like for transporting the glass substrate in the horizontal direction are installed on the lower surface side, there is a problem of blocking spraying on the substrate surface.

In addition, when the glass substrate to be formed becomes thinner, the allowable range of uniformity of the plate thickness also decreases, but there may be variations in the plate thickness on the lower surface side where the polishing liquid is blocked by an apparatus such as a roller transport. In order to minimize it, it has been considered to cope with it by optimizing the conveyance speed. However, when the transport speed is increased, the substrate may vibrate due to variations in the feed speed generated during transport and the slippage between the roller and the substrate. As the substrate becomes thinner, the substrate becomes minute around the substrate. There is a possibility that defects such as cracks are likely to occur. In addition, the effect of preventing cracks and the like can be expected by reducing the pitch of the roller conveyance, but since the area where the polishing liquid is blocked increases, the uniformity of the thickness after polishing on the lower surface side of the substrate decreases. There was a point.

Also, Japanese Patent Application Laid-Open No. 2008-13389 exists as a method for arranging the substrates vertically. Here, an etching apparatus capable of etching by discharging a shower-like hydrofluoric acid solution onto a glass substrate and an etching process using the etching apparatus, the spray angle of the shower, the interval between the shower nozzle and the substrate, the substrate By appropriately designing the swing amplitude length of the substrate, it is possible to uniformly supply the shower into the substrate surface, thereby suppressing the adhesion of fine particles (insoluble matter with respect to hydrofluoric acid) to the substrate surface. A technique capable of realizing uniform etching is disclosed.

According to this method, the above problem of blocking the polishing liquid by a conveying device such as a roller is solved, but the polishing liquid flows down while touching the substrate surface set in the vertical direction. The flow rate of the falling surface is slow and the flow rate is constant, but since the polishing liquid dripped by shower spray is added one after another under the substrate, the amount of liquid increases and the flow rate increases. As a result, there has been a problem that the polishing rate in the lower region of the substrate is increased, and the plate thickness varies between the upper and lower sides.

Furthermore, in Japanese Patent No. 3995146, a polishing component having an action of chemically polishing a glass substrate and a thickener having an action of increasing the solution viscosity are both contained at a constant concentration, and the viscosity is 5 × 10 ⁻¹ to 5 ×. A technique of applying a predetermined amount of a polishing liquid in a range of 10 ⁵ Pa · s on a glass substrate to advance a flattening reaction of the glass substrate, and cleaning the polishing liquid subjected to the flattening reaction after a predetermined time has elapsed. Is disclosed.

According to this method, the polishing liquid having a viscosity range of 5 × 10 ⁻¹ to 5 × 10 ⁵ Pa · s prevents dripping, and it is possible to prevent changes in the plate thickness between the upper and lower sides of the substrate. However, from the viewpoint of polishing efficiency and the viewpoint of non-uniform thickness at the end due to the formation of jig marks by the jig, the technique is not necessarily sufficient.

Therefore, it is possible to chemically polish the surface so that the glass substrate used in the liquid crystal display or organic EL display becomes a uniform thin film, increase the polishing efficiency, suppress the occurrence of jig marks, and at the same time reduce the risk of breakage. Development of a method and apparatus for polishing a glass substrate that has been suppressed has been desired.
JP 2013-252984 A JP 2008-13389 Japanese Patent No. 3995146

In order to solve the above problems, the object of the present invention is to enable the surface to be chemically polished so that a glass substrate used in a liquid crystal display or an organic EL display becomes a uniform thin film, and to generate jig traces. An object of the present invention is to provide a glass substrate polishing method and polishing apparatus with high polishing efficiency, which suppresses the risk of breakage at the same time.

In order to achieve the above object, a glass substrate polishing method according to the present invention includes a glass substrate polishing method for uniformly polishing a surface of a glass substrate used for a liquid crystal display or an organic EL display, wherein the glass substrate is suspended vertically. An installation step of lowering and fixing, a chemical polishing step of continuously spraying and applying a chemical polishing liquid for melting and polishing the glass substrate to both side surfaces of the glass substrate from a plurality of spray nozzles, and predetermined melt polishing A cleaning process for cleaning the glass substrate that has been melt-polished after a lapse of time, and the chemical polishing process is performed in order to prevent the occurrence of uneven spraying of the chemical polishing liquid due to dripping and the remaining of the glass substrate. The spray nozzle on the side is arranged so that the vertical interval or the horizontal interval is narrower than the lower end of the glass substrate, a large amount of chemical polishing liquid is injected to the upper end side, and the lower end side is less It is configured to injection.

The glass substrate polishing method according to the present invention is a glass substrate polishing method for uniformly polishing the surface of a glass substrate used in a liquid crystal display or an organic EL display, and the glass substrate is suspended and fixed vertically. An installation process, a chemical polishing process for continuously spraying and applying a chemical polishing liquid for melting and polishing the glass substrate to both side surfaces of the glass substrate from a plurality of spray nozzles, and cleaning the melt-polished glass substrate The chemical polishing step is performed by chemical polishing sprayed from a plurality of spray nozzles arranged at equal intervals in order to prevent the occurrence and non-uniformity of spray coating of chemical polishing liquid due to dripping. The amount of liquid is less than the amount of chemical polishing liquid sprayed from the spray nozzle on the upper end side of the glass substrate, and less than the amount of chemical polishing liquid sprayed from the spray nozzle on the lower end side of the glass substrate. It is also the configuration to Cum.

Further, the glass substrate is composed of a glass substrate for liquid crystal display in which liquid crystal is sealed in a gap between a CF substrate and a TFT substrate, or a glass substrate for organic EL display.
The chemical polishing liquid is configured to contain one or a plurality of melt polishing components selected from the group consisting of hydrofluoric acid, sulfuric acid, and hydrochloric acid.
Furthermore, the glass substrate polishing method is configured to block and remove latent scratches on the glass substrate by spraying and applying a chemical polishing solution containing sulfuric acid.

The glass substrate polishing apparatus according to the present invention is a glass substrate polishing apparatus for uniformly polishing the surface of a glass substrate used for a liquid crystal display or an organic EL display. And a plurality of spray nozzles for continuously spraying and applying a chemical polishing liquid for melt-polishing the glass substrate vertically from the glass substrate, and the melt-polished after the elapse of a predetermined melt-polishing time Cleaning means for cleaning the glass substrate, and the spray nozzle is configured to prevent the occurrence and non-uniformity of spray coating of the chemical polishing liquid due to liquid dripping, in order to prevent vertical or horizontal spacing of the spray nozzle on the upper end side of the glass substrate. Is arranged so as to be narrower than the vertical interval or horizontal interval of the injection nozzle at the lower end of the glass substrate, and a large amount of chemical polishing liquid is injected to the upper end side, and the lower end side It is configured to amount injection.

The glass substrate polishing apparatus according to the present invention is a glass substrate polishing apparatus for uniformly polishing the surface of a glass substrate used for a liquid crystal display or an organic EL display. And a plurality of spray nozzles for continuously spraying and applying a chemical polishing liquid for melt-polishing the glass substrate vertically from the glass substrate, and the melt-polished after the elapse of a predetermined melt-polishing time The spray nozzle is sprayed from a plurality of spray nozzles arranged at equal intervals in order to prevent the occurrence and non-uniformity of spray coating of the chemical polishing liquid due to liquid dripping. The amount of the chemical polishing liquid to be injected from the injection nozzle on the lower end side of the glass substrate is larger than the amount of the chemical polishing liquid injected from the injection nozzle on the upper end side of the glass substrate. It is also configured to reduce injection amount of the liquid.

The installation means includes side fixing means for supporting the left and right edges of the glass substrate, and bottom fixing means for supporting the lower edge of the glass substrate, and the side fixing means covers both surfaces of the glass substrate. The bottom fixing means is formed of a mounting base for mounting the bottom of the glass substrate. It is the composition which becomes.
Furthermore, the spray nozzle has a configuration in which the tip ports of the plurality of spray nozzles installed at equal intervals have a large tip diameter of the top nozzle and a small tip diameter of the bottom nozzle.

Since the glass substrate polishing method and polishing apparatus according to the present invention are configured as described in detail above, they have the following effects.
1. Since the chemical polishing liquid is spray-applied from both sides to the glass substrate suspended in the installation process by a plurality of spray nozzles, the chemical polishing liquid can be uniformly applied to the glass substrate. Further, since the vertical interval or the horizontal interval of the spray nozzles on the upper end side of the glass substrate is arranged so as to be narrower than the lower end of the glass substrate, it is possible to prevent the occurrence and non-uniformity of spray coating of the chemical polishing liquid due to dripping. .
2. The amount of chemical polishing liquid sprayed from a plurality of spray nozzles is configured to spray the upper end side of the glass substrate more than the amount of the lower end side, thereby preventing the occurrence and non-uniformity of spray coating of the chemical polishing liquid due to dripping. It becomes possible.

3. Since the glass substrate is a glass substrate for a liquid crystal display or a glass substrate for an organic EL display, the glass substrate used for various displays can be polished.
4). Since the chemical polishing liquid is configured to contain a melt polishing component such as hydrofluoric acid, sulfuric acid, and hydrochloric acid, it can be used from a hydrochloric acid-based polishing liquid having a small specific gravity to a sulfuric acid-based polishing liquid having a large specific gravity.

5. Since the chemical polishing liquid containing sulfuric acid is applied by spraying, it is possible to enjoy the effect of suppressing polishing in the recesses during polishing against latent scratches and abnormalities (pits) generated on the glass substrate. .
6). Since the plurality of spray nozzles for spraying and applying the chemical polishing liquid from both sides are provided on the glass substrate suspended by the installation means, the chemical polishing liquid can be uniformly applied to the glass substrate. Further, since the vertical interval or the horizontal interval of the spray nozzles on the upper end side of the glass substrate is arranged so as to be narrower than the lower end of the glass substrate, it is possible to prevent the occurrence and non-uniformity of spray coating of the chemical polishing liquid due to dripping. . In addition, space saving of the apparatus can be achieved, and the polishing apparatus can be configured by partial modification or correspondence of the conventional polishing apparatus (batch method).

7). The multiple spray nozzles that spray chemical polishing liquid spray the upper end side of the glass substrate more than the amount on the lower end side, so it is possible to prevent the occurrence of uneven spraying of chemical polishing liquid due to liquid dripping and remaining. It becomes.
8). Since the installation means is composed of side fixing means consisting of a shallow groove having a substantially triangular cross section and bottom fixing means consisting of a mounting base on which the bottom of the glass substrate is placed, jig traces caused by chemical polishing are removed. Occurrence can be suppressed.

9. Since the top ends of the plurality of spray nozzles are made larger at the upper end side and smaller at the lower end side, it is possible to prevent the occurrence and non-uniformity of spray coating of the chemical polishing liquid due to liquid dripping.

Hereinafter, a glass substrate polishing method 100 and a polishing apparatus 200 according to the present invention will be described in detail based on embodiments shown in the drawings.
FIG. 1 is a flow diagram of a glass substrate polishing method according to the present invention, and FIG. 2 is a conceptual diagram of a glass substrate polishing apparatus. FIG. 3 is a cross-sectional view of the side surface of the glass substrate, and FIG. 4 is a side view of the injection nozzle with the installation interval optimized. FIG. 5 is a side view of an injection nozzle that optimizes the injection amount of the polishing liquid, and FIG.

As shown in FIG. 1, a glass substrate polishing method 100 according to the present invention includes a polishing method 100, a chemical polishing step 120, and a cleaning step 130, and the surface of the glass substrate 10 used for a liquid crystal display or an organic EL display. Is a polishing method for polishing at a uniform and uniform thickness.

The glass substrate 10 to be polished is first placed in a state where it can be processed in the installation step 110. The installation step 110 is a step of hanging and fixing the glass substrate 10 vertically. The glass substrate 10 has a thickness of 1 to several mm before polishing. Through this process, the glass substrate 10 to be polished is fixed by a jig until polishing is completed.

The glass substrate 10 fixedly installed in the installation step 10 is then processed in a chemical polishing step 120 as shown in FIG. The chemical polishing step 120 is a step of melting and polishing the glass substrate 10 with the chemical polishing liquid 200, and is directed to the glass substrate 10 installed vertically from the plurality of jet nozzles 220 over the entire surface from both sides. The glass substrate 10 is melt-polished by spraying 20. In the present embodiment, the chemical polishing liquid 20 is continuously spray-applied from a plurality of spray nozzles 220 to both side surfaces of the glass substrate 10 for a predetermined time. The sprayed chemical polishing liquid 20 is applied to the glass substrate 10, then flows through the glass substrate 10 and is accumulated in a waste liquid accumulating means (not shown) installed below. As a result, the chemical polishing liquid 20 is always sprayed onto the glass substrate 10 to continue polishing, and efficient chemical polishing can be performed.

In this embodiment, the chemical polishing process 120 is continuously performed for about 5 to 120 minutes. However, the processing time is not limited to this, and the process is not continuous. Alternatively, it may be configured to perform processing intermittently (intermittently) at regular intervals.

The glass substrate 10 subjected to the chemical polishing process in the chemical polishing process 120 is then processed in the cleaning process 130 shown in FIG. The cleaning step 130 is a step for cleaning and removing the chemical polishing liquid 20 and the reaction product attached to the surface of the glass substrate 10 that has been dissolved and polished. After the elapse of a predetermined melt polishing time in the chemical polishing step 120, the glass substrate 10 that has been melt polished is cleaned. Thereby, the progress of chemical polishing can be interrupted to complete the polishing process.

The chemical polishing step 120 and the cleaning step 130 of the glass substrate 10 can be repeatedly performed. Thereby, it is possible to improve the effect of polishing and cleaning the glass substrate 10. Note that both the chemical polishing liquid 20 used in the chemical polishing process 120 and the cleaning liquid (not shown) of the chemical polishing liquid 20 used in the cleaning process 130 flow to the waste liquid storage means, but both are mixed. In order to suppress this, it is possible to adopt a structure in which the waste liquid piping is switched in each step. With this structure, the waste liquid can be reused efficiently.

As previously described, there is a chemical polishing method that uses a glass substrate in the horizontal direction and conveys the polishing liquid from above and below by applying a shower method, as described above. If the substrate thickness is a glass substrate product having a thickness of, for example, about 0.3 mm, problems such as non-uniformity in plate thickness caused by the difference in polishing characteristics between the upper and lower surfaces, that is, the difference in polishing speed, and the like hardly occur. It was a level.

However, in glass substrate products and the like that are required to be polished thinner than 0.3 mm, for example, when the plate thickness is about 0.25 mm, the thickness of the laminated single plate is about 0.125 mm for each of the upper and lower substrates. However, the strength at the edge of the substrate suddenly decreases. For this reason, there is a problem that a difference occurs in the plate thickness between the upper and lower sides due to the difference in polishing characteristics between the upper and lower substrates of the bonded substrate. Furthermore, even in such a situation, in order to maintain the required standard value of the total thickness of the substrate, it is necessary to finish the substrate that is likely to be thinned further and bring the total thickness within the standard value. There has been a problem of the strength of the substrate, particularly that the strength of the end portion of the substrate is lowered.

By adopting a configuration in which the glass substrate 10 is installed vertically as in the present invention, such a problem is solved, and it is possible to perform chemical polishing uniformly on any surface, in order to meet the required standard. As a result of this polishing, it was possible to solve the problem that the strength of the glass substrate was impaired.

In this embodiment, the chemical polishing step 120 is arranged such that the vertical interval or the horizontal interval of the injection nozzles 220 on the upper end side of the glass substrate 10 is narrower than the lower end of the glass substrate 10, and the chemical polishing liquid is applied to the glass substrate 10. 20 is spray-coated. With this configuration, the chemical polishing liquid 20 can be sprayed in a large amount on the upper end side of the glass substrate 10 and can be sprayed in a small amount on the lower end side of the glass substrate 10.

When the chemical polishing liquid 20 is sprayed and applied with the glass substrate 10 installed vertically, the chemical polishing liquid 20 flows down while touching the surface of the glass substrate 10 set in the vertical direction. In the area above 10, the falling velocity of the surface is slow and the flow rate is constant, but the chemical polishing liquid 20 dripped by spray coating is successively added below the glass substrate 10. For this reason, the flow rate increases as the amount of liquid increases. As a result, since the polishing rate in the lower region of the glass substrate 10 is increased, there has been a problem that the plate thickness becomes uneven between the upper and lower sides of the glass substrate 10.

According to the present embodiment, a large amount of chemical polishing liquid 20 is sprayed and applied to the upper part of the glass substrate 10, and a small amount of chemical polishing liquid 20 is applied to the lower part of the glass substrate 10. The amount of distribution was optimized, it was possible to prevent the occurrence and non-uniformity of spray coating of the chemical polishing liquid 20 due to dripping, and to suppress variations in the polishing thickness.

As another example of the glass substrate polishing method 100 according to the present invention, a plurality of spray nozzles 220 are installed at equal intervals with respect to the glass substrate 10 and then sprayed from the plurality of spray nozzles 220. By controlling the amount of the chemical polishing liquid 20, the amount of the chemical polishing liquid 20 injected from the injection nozzle 222 a positioned on the upper end side of the glass substrate 10 is injected from the injection nozzle 222 b positioned on the lower end side of the glass substrate 10. It is possible to adopt a configuration in which a small amount of the chemical polishing liquid 20 is sprayed.

As described above, when the chemical polishing liquid 20 is sprayed and applied evenly to the upper and lower regions of the glass substrate 10, the polishing rate of the lower region of the glass substrate 10 is higher than that of the upper region of the glass substrate 10. Therefore, there has been a problem that the thickness of the glass substrate 10 is not uniform between the upper and lower sides. By adopting the configuration of the present invention, a large amount of the chemical polishing liquid 20 is sprayed and applied to the upper part of the glass substrate 10 and a small amount of the chemical polishing liquid 20 is applied to the lower part of the glass substrate 10. The amount of application and distribution of the liquid 20 can be optimized, the occurrence and non-uniformity of spray application of the chemical polishing liquid 20 due to liquid dripping can be prevented, and variations in the polishing thickness can be suppressed. .

The glass substrate 10 according to the present embodiment can be a glass substrate for a liquid crystal display in which liquid crystal 16 is sealed in the gap between the CF substrate 12 and the TFT substrate 14 as shown in FIG. It is of course possible to use a glass substrate for an organic EL display.

Thus, it becomes possible to polish and manufacture glass substrates used in various displays, and it is possible to configure a glass substrate polishing method 100 that can meet all requirements.

In addition, in order to form a liquid crystal with a uniform thickness, a liquid crystal display is formed by bonding two substrates, a CF (color filter) substrate and a TFT (thin transistor) substrate, and forming a gap between the substrates. A liquid crystal is sealed in the gap. This is a manufacturing method in which the finally bonded substrates are chemically polished (etched) from both sides to reduce the thickness. The finished thickness after polishing (thickness of the finished product) has been generally about 0.3 to 0.6 mm. However, in response to recent market demands, especially the demand for thinner substrates. The number of products that finish thinner than 0.3 mm is increasing. By thinly polishing the bonded substrate, for example, a touch panel can be built in the substrate, and a product having various functions can be developed.

The chemical polishing liquid 20 can be a liquid material containing one or a plurality of molten polishing components selected from the group consisting of hydrofluoric acid, sulfuric acid, and hydrochloric acid. As a result, it is possible to use a hydrochloric acid-based polishing liquid having a small specific gravity to a sulfuric acid-based polishing liquid having a large specific gravity, and any chemical polishing liquid 20 can be used depending on the situation such as the thickness of the object to be polished and the polishing speed. It is possible to polish the glass substrate efficiently.

In particular, as an embodiment of the glass substrate polishing method 100 according to the present invention, a chemical polishing liquid 20 containing sulfuric acid can be applied by spraying. As a result, it is possible to obtain an effect of additionally closing and closing latent scratches on the glass substrate 10 and to obtain an effect of preventing damage cracks and the like caused by existing slight damage. In addition, it is possible to enjoy the effect of suppressing polishing in the recesses during polishing against latent scratches and abnormalities (pits) generated in the glass substrate 10 during polishing.

Next, the glass substrate polishing apparatus 200 according to the present invention will be described. As shown in FIG. 2, the glass substrate polishing apparatus 200 includes an installation unit 210, an injection nozzle 220, and a cleaning unit 230. The surface of the glass substrate 10 used for a liquid crystal display or an organic EL display is made uniform and uniform. Grind.

The installation means 210 is a member for vertically suspending and fixing the glass substrate 10 to be polished. As shown in FIG. 2, in this embodiment, the installation means 210 provided on the frame 240 is provided. Thus, the upper side surfaces and the bottom of the glass substrate 10 are fixedly installed on the frame 240. The glass substrate 10 has a thickness of 1 to several mm before polishing, and the glass substrate 10 is fixed by the jig of the installation means 210 until polishing is completed. The installation means 210 does not necessarily have to be installed on the frame 240, and a configuration using a dedicated frame jig (not shown) that supports the glass substrate 10 having the same function may be used. Further, it is conceivable that the installation means 210 is provided on the frame jig, and the same effect can be expected by this configuration.

The spray nozzle 220 is a narrow opening for spray-coating the chemical polishing liquid 20 for melting and polishing (chemical polishing) the glass substrate 10 onto the glass substrate 10, and is shown in FIGS. 2, 4, and 5. As described above, a plurality of chemical polishing liquids 20 are installed at positions where the chemical polishing liquids 20 are sprayed perpendicularly to the glass substrate 10, and the chemical polishing liquids 20 are sprayed and applied evenly and continuously on both side surfaces of the glass substrate 10. As a result, the chemical polishing liquid 20 is spray-applied over the entire surface of both surfaces of the glass substrate 10, and melt polishing (chemical polishing) of the glass substrate 10 becomes possible.

In the present embodiment, the plurality of spray nozzles 220 are configured to continuously spray and apply the chemical polishing liquid 20 to both sides of the glass substrate 10 for a certain period of time. The sprayed chemical polishing liquid 20 is applied to the glass substrate 10, then flows through the glass substrate 10 and is accumulated in a waste liquid accumulating means (not shown) installed below. With this configuration, the chemical polishing liquid 20 is always sprayed onto the glass substrate 10 and the glass substrate 10 continues chemical polishing over the entire surface, thereby enabling efficient chemical polishing.

In the present embodiment, the chemical polishing liquid 20 is continuously sprayed and applied from the spray nozzle 220 to the glass substrate 10 for about 5 to 120 minutes, but this processing time is limited. It is also possible to adopt a configuration in which processing is performed intermittently (intermittently) at regular intervals instead of continuously.

The cleaning means 230 is for cleaning the glass substrate 10 melt-polished with the chemical polishing liquid 20 and washing away the chemical polishing liquid 20. The chemical polishing liquid 20 and the reaction adhered to the surface of the glass substrate 10 that has been dissolved and polished. Means for washing away product. After performing chemical polishing for a predetermined time by spraying the chemical polishing liquid 20 from the spray nozzle 220, cleaning is performed by spraying the cleaning liquid toward the glass substrate 10 that has been melt polished. Thereby, the progress of chemical polishing can be interrupted to complete the polishing process.

It is possible to adopt a configuration in which the dissolution polishing processing of the glass substrate 10 by spraying and applying the chemical polishing liquid 20 from the spray nozzle 220 and the cleaning processing of the glass substrate 10 by the cleaning means 230 are repeatedly performed. Thereby, it is possible to improve the effect of polishing and cleaning the glass substrate 10. Both the chemical polishing liquid 20 spray-applied from the spray nozzle 220 and the cleaning liquid (not shown) of the chemical polishing liquid 20 used in the cleaning means 230 flow to the waste liquid storage means (not shown). However, in order to prevent both from being mixed and discarded, it is possible to adopt a structure in which the waste liquid piping is switched. With this structure, the waste liquid can be discarded or reused efficiently.

The cleaning means 230 may be configured to perform a cleaning process by switching the method of supplying the chemical polishing liquid 20 and spraying the cleaning liquid (not shown) from the spray nozzle 220 to spray the glass substrate 10. is there. Further, it is possible to spray and supply the cleaning liquid (not shown) to the glass substrate 10 using a completely different cleaning liquid supply pipe (supply nozzle, not shown), and in particular, the method for spraying and supplying the cleaning liquid is limited. It is not a thing.

In the present embodiment, as shown in FIG. 4, the injection nozzle 220 is configured so that the vertical interval or the horizontal interval of the injection nozzle 222 a located on the upper end side of the glass substrate 10 is the same as that of the injection nozzle 222 b located on the lower end side of the glass substrate 10. It is the structure arrange | positioned so that it may become narrower than a vertical space | interval or a horizontal space | interval. With this configuration, a large amount of the chemical polishing liquid 20 is sprayed to the upper end side of the glass substrate 10 and a small amount is sprayed to the lower end side of the glass substrate 10. As a result, it is possible to prevent the occurrence and non-uniformity of spray coating of the chemical polishing liquid 20 due to liquid dripping and to suppress the variation in the polishing thickness.

That is, when the chemical polishing liquid 20 is sprayed and applied from the side to the glass substrate 10 with the glass substrate 10 installed vertically as in the polishing apparatus according to the present invention, the chemical polishing liquid 20 However, it flows down on the surface of the glass substrate 10 set in the vertical direction. At this time, in the upper region of the glass substrate 10, the falling velocity of the surface is slow and the flow rate is constant, but on the lower side of the glass substrate 10, the glass substrate is combined with the chemical polishing liquid 20 applied directly by spraying. Since the chemical polishing liquid 20 spray-applied on the upper part of the substrate 10 is in a state of being added one after another, the amount of liquid flowing on the surface of the lower part of the glass substrate 10 is increased and the flow velocity is also increased. As a result, since the polishing rate in the lower region of the glass substrate 10 is increased, there has been a problem that the thickness of the glass substrate 10 is not uniform between the upper and lower sides.

According to the present embodiment, a large amount of chemical polishing liquid 20 is sprayed and applied to the upper part of the glass substrate 10, but a small amount of chemical polishing liquid 20 is applied to the lower part of the glass substrate 10. The amount of the polishing liquid 20 applied and distributed is optimized, and the occurrence and non-uniformity of spray coating of the chemical polishing liquid 20 due to liquid dripping can be prevented and variation in the polishing thickness can be suppressed.

As another example of the glass substrate polishing apparatus 200 according to the present invention, as shown in FIG. 5, a plurality of injection nozzles 220 are installed at equal intervals with respect to the glass substrate 10. By controlling the amount of the chemical polishing liquid 20 sprayed by the spray nozzle 220, the spray located on the lower end side of the glass substrate 10 from the amount of the chemical polishing liquid 20 sprayed by the spray nozzle 222a positioned on the upper end side of the glass substrate 10. It is possible to reduce the amount of the chemical polishing liquid 20 ejected by the nozzle 222b.

As described above, when the chemical polishing liquid 20 is sprayed and applied evenly to the upper and lower regions on the glass substrate 10, the glass is higher than the upper region of the glass substrate 10 due to the application amount and flow rate of the chemical polishing liquid 20. Since the polishing rate in the lower region of the substrate 10 is increased, there has been a problem that the plate thickness varies between the upper and lower sides of the glass substrate 10. With the above configuration, a large amount of the chemical polishing liquid 20 is sprayed and applied to the upper part of the glass substrate 10, and a small amount of the chemical polishing liquid 20 is applied to the lower part of the glass substrate 10. It is possible to optimize the amount of application and distribution of the liquid, and to prevent the occurrence and non-uniformity of spray application of the chemical polishing liquid 20 due to liquid dripping and to suppress the variation in the polishing thickness.

As shown in FIG. 6, the installation means 210 can be configured by side fixing means 212 and bottom fixing means 214. The side fixing means 212 is a member for fixing and supporting the glass substrate 10 with the left and right edges sandwiched therebetween. In this embodiment, both sides of the glass substrate 10 are covered to prevent spraying of the chemical polishing liquid 20. The glass substrate 10 is sandwiched from both ends while being in contact with the left and right edge corners of the glass substrate 10 so that the shape is a notch shallow groove having a substantially triangular cross section.

Conventionally, when the glass substrate 10 is fixed when the glass substrate 10 is chemically polished, the glass substrate 10 is fixedly held by a fixing means including a deep groove. According to this configuration, the fixing means partially covers both side surfaces of the glass substrate 10, and spray application of the chemical polishing liquid 20 is hindered, and a mark of a jig for holding the glass substrate 10 is left on the glass substrate 10. There is a problem in that it is formed in the region of the left and right end portions.

As in the present invention, the side fixing means 212 is formed as a notch shallow groove having a substantially triangular cross section and the length of the side fixing means 212 is shortened, so that the spray coating of the chemical polishing liquid 20 is not hindered. It has become possible to configure a glass substrate polishing apparatus 200 in which jig traces are prevented from remaining.

Further, the bottom fixing means 214 is a member for supporting the lower edge of the glass substrate 10, and is configured by a mounting base on which the bottom of the glass substrate 10 is placed.
Conventionally, similarly to the side fixing means 212, the bottom of the glass substrate 10 is fixed by fixing means including deep grooves. By firmly fixing the glass substrate 10 with such a structure, it was possible to prevent the glass substrate 10 from falling off during chemical polishing by bubbling or the like. There was a problem of causing 10 damage.

In the present invention, the bottom fixing means 214 has a mounting base shape, so that the spray coating of the chemical polishing liquid 20 is not hindered, and the glass substrate 10 is prevented from being damaged due to clamping by the fixing means. It becomes possible to constitute the polishing apparatus 200 for a glass substrate.

As still another embodiment of the glass substrate polishing apparatus 200 according to the present invention, the front end ports of the plurality of spray nozzles 220 installed at equal intervals increase the front end diameter of the upper end side spray nozzles 222a, and the lower end side sprays. It is possible to make the tip diameter of the nozzle 222b small. Even in this configuration, as described above, a large amount of the chemical polishing liquid 20 is spray-applied to the upper portion of the glass substrate 10 and a small amount of the chemical polishing liquid 20 is applied to the lower portion of the glass substrate 10. The amount of application and distribution of the polishing liquid 20 can be optimized, the occurrence and non-uniformity of spray application of the chemical polishing liquid 20 due to dripping can be prevented, and the variation in the polishing thickness can be suppressed. It was.

With the above configuration, it is possible to polish the glass substrate 10 more efficiently than the conventional method of bubbling by immersing the glass substrate in a solution.

The variation in the thickness of the glass substrate 10 after chemical polishing needs to be reduced as the finished thickness is reduced. For example, when the plate thickness at the start of polishing is 1 mm, the plate thickness of the finish is 0.4 mm, and the allowable variation of the plate thickness is 10% of the finish thickness, the variation allowable value is plus or minus 0.00. 04 mm or less. On the other hand, the polishing amount is 0.6 mm, and assuming that the variation of the substrate plate thickness before polishing is zero, the tolerance rate for realizing the variation within 0.04 mm over the entire surface of the substrate material is 0.6 mm. 0.067 (allowable variation / polishing amount).

In the case of 0.3 mm finishing, if the allowable range of variation is 10% of the finishing thickness, it will be 0.03 mm or less. Although the polishing amount is 0.7 mm, the allowable variation with respect to the polishing amount is 0.03 mm, and the allowable rate is 0.043 (allowable variation / polishing processing amount). Strict values are required for each stage. Furthermore, when the finished thickness is 0.25 mm, the allowable variation with respect to the polishing amount of 0.75 mm is 0.025, and the allowable rate is 0.033 (allowable variation / polishing processing amount). Even slight variations are ignored. It will not be possible.

Further, when the liquid crystal display is polished, the required error is small even with respect to the difference in thickness between both the CF side substrate and the TFT side substrate. For example, when a 1 mm liquid crystal display is polished, if a difference in the plate thickness is generated by about 1% of the polishing amount, a difference of 6 μ of 1% of the polishing amount of 600 μ is generated in the case of 0.4 mm finishing. . When the total allowable amount is plus or minus 40 μ and the allowable range is 80 μ, the allowable range is actually 74 μ (80−6) in consideration of the difference of 6 μ between the thicknesses of both substrates.

Similarly, in the case of 0.3mm finishing, 7% of 1% of the polishing amount is drawn to 53μ (60-7) with respect to the allowable range 60μ, and when the finishing thickness is 0.25mm, the allowable range However, 7.5%, which is 1% of the polishing amount, is drawn to 50μ to 42.5μ (50-7.5), and as the thickness is reduced, variation must be strictly suppressed.

Furthermore, in the case of 0.25 μ finish, the CF side and TFT side substrates will be finished at 0.125 mm if there is no difference in thickness, but if there is a difference in thickness, there will be variations on the thin side. In some cases, there is a problem that the strength is weakened. When the plate thickness is about 0.1 mm (100 μm), the strength of the end portion of the substrate becomes considerably weak, and the risk of breakage increases.

For example, in the manufacturing process with a finishing thickness of about 0.3 to 0.6 mm, although there was little variation that would not be a problem, products with a thickness of 0.3 mm or less are now produced, especially as demand for thin substrates increases. In this case, it is strictly required to suppress the variation in the polishing amount.

By using the glass substrate polishing method and polishing apparatus according to the present invention, it is possible to suppress the above-described variation, more efficient than the conventional bubbling method and other prior art, It has become possible to provide a glass substrate polishing method and a polishing apparatus that can produce a product with no unevenness in polishing thickness variation.

Flow chart of glass substrate polishing method according to the present invention Conceptual diagram of glass substrate polishing equipment Cross section of side of glass substrate Side view of injection nozzle with optimized installation interval Side view of the injection nozzle with optimized polishing liquid injection amount The perspective view which shows the structure of an installation means

DESCRIPTION OF SYMBOLS 10 Glass substrate 12 CF substrate 14 TFT substrate 16 Liquid crystal 20 Chemical polishing liquid 100 Glass substrate polishing method 110 Installation process 120 Chemical polishing process 130 Cleaning process 200 Glass substrate polishing apparatus 210 Installation means 212 Side fixing means 214 Bottom fixing means 220 Spray nozzle 222a Spray nozzle 222b Spray nozzle 230 Cleaning means 240 Frame

Claims (9)

1. A glass substrate polishing method (100) for uniformly polishing the surface of a glass substrate used for a liquid crystal display or an organic EL display,
   An installation step (110) for vertically suspending and fixing the glass substrate (10), and a chemical polishing liquid (20) for melting and polishing the glass substrate from a plurality of spray nozzles (220). A chemical polishing step (120) for continuously spray-coating on both side surfaces, and a cleaning step (130) for cleaning the glass substrate that has been melt-polished after elapse of a predetermined melt-polishing time,
   In the chemical polishing step (120), in order to prevent unevenness and remaining of the spray coating of the chemical polishing liquid due to liquid dripping, the vertical interval or the horizontal interval of the spray nozzle (220) on the upper end side of the glass substrate (10) is set to glass A method for polishing a glass substrate, wherein the glass substrate is disposed so as to be narrower than a lower end of the substrate, and a large amount of chemical polishing liquid is sprayed to the upper end side and a small amount is sprayed to the lower end side.
2. A glass substrate polishing method (100) for uniformly polishing the surface of a glass substrate used for a liquid crystal display or an organic EL display,
   An installation step (110) in which the glass substrate is suspended and fixed vertically, and a chemical polishing liquid for melting and polishing the glass substrate is continuously applied to both sides of the glass substrate from a plurality of spray nozzles (220). A chemical polishing step (120) for spray coating, and a cleaning step (130) for cleaning the melt-polished glass substrate,
   In the chemical polishing step (120), in order to prevent the occurrence and non-uniformity of spray coating of the chemical polishing liquid due to liquid dripping, the chemical polishing liquid sprayed from a plurality of spray nozzles (220) installed at equal intervals is used. A method for polishing a glass substrate, wherein the amount of chemical polishing liquid sprayed from the spray nozzle on the lower end side of the glass substrate is sprayed less than the amount of chemical polishing liquid sprayed from the spray nozzle on the upper end side of the glass substrate .
3. The glass substrate (10) comprises a glass substrate for liquid crystal display in which liquid crystal is sealed in a gap between a CF substrate (12) and a TFT substrate (14), or a glass substrate for organic EL display. Or the polishing method of the glass substrate of Claim 2.
4. 3. The glass substrate polishing according to claim 1, wherein the chemical polishing liquid (20) contains one or a plurality of molten polishing components selected from the group consisting of hydrofluoric acid, sulfuric acid, and hydrochloric acid. Method.
5. 2. The glass substrate polishing method (100) according to claim 1 or claim 2, wherein the glass substrate is subjected to a chemical polishing solution (20) containing sulfuric acid by spray coating so as to block and remove latent scratches on the glass substrate. 2. The method for polishing a glass substrate according to 2.
6. A glass substrate polishing apparatus (200) for uniformly polishing the surface of a glass substrate used for a liquid crystal display or an organic EL display,
   Installation means (210) for vertically suspending and fixing the glass substrate (10), and chemical polishing liquid (20) for melting and polishing the glass substrate (10) on both side surfaces of the glass substrate (10) A plurality of spray nozzles (220) for continuously spraying and applying vertically, and a cleaning means (230) for cleaning the glass substrate that has been melt-polished after elapse of a predetermined melt-polishing time,
   The spray nozzle (220) has a vertical interval or a horizontal interval between the spray nozzles (222a) on the upper end side of the glass substrate in order to prevent the occurrence and non-uniformity of spray application of the chemical polishing liquid (20) due to dripping. Glass substrate polishing characterized by being arranged so as to be narrower than the vertical interval or horizontal interval of the injection nozzle (222b) at the lower end, and spraying a large amount of chemical polishing liquid on the upper end side and a small amount on the lower end side apparatus.
7. A glass substrate polishing apparatus (200) for uniformly polishing the surface of a glass substrate used for a liquid crystal display or an organic EL display,
   An installation means (210) for vertically suspending and fixing the glass substrate (10), and a chemical polishing liquid for melting and polishing the glass substrate (10) continuously from both side surfaces of the glass substrate. A plurality of spray nozzles (220) for spray coating, and a cleaning means (230) for cleaning the glass substrate that has been melt polished after a predetermined melt polishing time,
   The spray nozzle (220) is a chemical polishing sprayed from a plurality of spray nozzles (220) installed at equal intervals in order to prevent generation and remaining of spray coating unevenness of the chemical polishing liquid (20) due to dripping. The amount of the liquid is sprayed so that the amount of the chemical polishing liquid sprayed from the spray nozzle (222b) on the lower end side of the glass substrate is smaller than the amount of the chemical polishing liquid sprayed from the spray nozzle (222a) on the upper end side of the glass substrate. An apparatus for polishing a glass substrate.
8. The installation means (210) comprises side fixing means (212) for supporting the left and right edges of the glass substrate and bottom fixing means (214) for supporting the lower edge of the glass substrate. ) Is formed of a notch shallow groove having a substantially triangular cross section that is in contact with the left and right edge corners of the glass substrate at positions where both side surfaces of the glass substrate (10) are not covered and is sandwiched from both ends, and the bottom fixing means (214) The glass substrate polishing apparatus according to claim 6 or 7, comprising a mounting base for mounting the bottom of the glass substrate (10).
9. The spray nozzle (220) has a plurality of spray nozzles arranged at equal intervals, the tip opening of the spray nozzle (222a) on the upper end side is increased, and the tip opening diameter of the spray nozzle (222b) on the lower end side is decreased. The glass substrate polishing apparatus according to claim 6 or 7, wherein the glass substrate polishing apparatus is a glass substrate polishing apparatus.
   
   
   

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