JP2017218351A - Production method of glass substrate, and glass substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve production efficiency by uniformly roughening a surface of a large area glass substrate without strength degradation, and conducting treatment necessary for the surface roughening in a short time.SOLUTION: In roughening one main surface Ga of two main surfaces Ga, Gb of a glass substrate G by etching treatment, an atomized etchant E is supplied to the one main surface Ga such that an untreated surface 17 constituting the one main surface Ga just before supply of the atomized etchant E remains between regions to which the atomized etchant E has been adhered.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a glass substrate manufacturing method and a glass substrate, and more particularly to a technique for roughening a glass substrate by etching.

  For example, in a glass substrate made of non-alkali glass, static charging may be a problem. Glass that is an insulator is very easily charged. However, an alkali-free glass that does not substantially contain an alkali metal oxide has a property of being particularly easily charged, and the charged electric charge tends to be held without escaping.

  In the manufacturing process of a liquid crystal display, an organic EL display, and the like, charging of the glass substrate occurs in various processes, which is a problem. In particular, so-called peeling electrification that occurs at the time of contact peeling with a metal or ceramic (insulator) plate in a film forming process or the like is a serious problem. Since the voltage at the time of charging can reach several tens of kV at the maximum, breakdown (dielectric breakdown) of various elements and electrode wires formed on the main surface (the definition will be described later) of the glass substrate by discharge or the glass substrate itself. Or electrostatic breakdown) may occur.

  In addition, a glass substrate having a smooth main surface is likely to stick to a metal or ceramic plate, and problems such as breakage of the glass substrate may occur when the glass substrate is peeled off (peeled). If the glass substrate is charged, there is a risk of promoting sticking to the plate. Therefore, in order to reduce the contact area between the glass substrate and the plate and prevent this kind of breakage as much as possible, various types of main surfaces of the main surface of the glass substrate where various elements and electronic circuits are not formed The roughening process is performed.

  Specifically, a method of forming minute irregularities on the main surface by polishing with a roll brush or the like on the main surface fixed to the stage among the two main surfaces of the glass substrate (for example, Patent Documents) 1), a method of immersing the main surface of the glass substrate using a predetermined chemical solution, and eroding the main surface to roughen the surface (for example, see Patent Document 2), or fluorine. A method of increasing the surface roughness Ra of the main surface by subjecting the main surface of the glass substrate to chemical treatment with a plasma generated under atmospheric pressure using a gas containing gas as a source (for example, Patent Document 2) Have been proposed or actually made.

JP 2001-343632 A Japanese Patent No. 5679513

  However, when performing physical roughening (roughening by polishing) as described in Patent Document 1, fine cracks called latent scratches may occur on the main surface of the treated glass substrate. is there. This type of crack may cause a reduction in strength of the glass substrate.

  If chemical treatment (immersion treatment) using a chemical solution as described in Patent Document 2, fine cracks such as latent scratches do not occur, and therefore surface roughening treatment is performed without causing strength reduction. Can do. However, when immersion treatment is performed on a glass substrate using a chemical solution, the influence of the scattering of the chemical solution on the priority guarantee surface of the glass substrate (here, the main surface opposite to the main surface to be processed) In addition, it is necessary to pay attention to the safety of the work environment, resulting in problems such as a reduction in work efficiency and an increase in cost for safety measures. In addition, considering the recent increase in the size of glass substrates for liquid crystal displays (sizes exceeding 2 m square), the so-called wet process such as the dipping process described above can be performed uniformly on the main surface of a large area glass substrate. It was very difficult to process.

  On the other hand, the chemical treatment by atmospheric pressure plasma using a fluorine-containing gas as a source is suitable for chemically treating the main surface of a glass substrate having a large area as compared with the immersion treatment described above, but the main surface Since the source for treating the gas is a gas, there is a problem that unintentional chemical treatment bias occurs. Further, since the chemical treatment is performed using gas as a source, the time required for the treatment is long, and there is a problem in terms of production efficiency.

  In view of the above circumstances, in the present specification, the glass substrate having a large area is uniformly roughened without causing a reduction in strength, and the processing necessary for the roughening is performed in a short time, thereby improving the production efficiency. Improvement is a technical issue to be solved.

  The solution of the technical problem is achieved by the glass substrate manufacturing method according to the present invention. That is, in this manufacturing method, when one of the two main surfaces of the glass substrate is subjected to etching treatment to roughen the surface, a finely divided etching solution is supplied to one of the main surfaces to form fine particles. It is characterized in that an untreated surface constituting one main surface immediately before supplying the finely divided etching solution remains between the regions where the etched etching solution is adhered. In addition, the “main surface” in the present specification means two surfaces of the surface of the glass substrate that are oriented in opposite directions in the thickness direction of the glass substrate. In addition, the “untreated surface” in the present specification includes a molded surface (also referred to as a fired surface) of a glass substrate, a polished surface in which a trace is left after polishing after forming.

  As a result of earnestly examining the surface roughening technology by the chemical treatment described above, the present inventor has found that even if the entire surface of the glass substrate is not eroded by immersion as in the prior art, the minute corrosion areas are randomly distributed. It has been found that the contact area with a plate or the like can be reduced to such an extent that peeling charge can be effectively suppressed. The present invention has been made on the basis of the above knowledge, and one main surface is etched by supplying finely divided etching solution. Thereby, for example, a large number of corroded surfaces as randomly distributed corroded areas can be formed on one main surface. Accordingly, the entire surface of one main surface can be uniformly roughened with the etching solution. In addition, in the present invention, since the etching solution is supplied so that the untreated surface remains between the regions where the etching solution is adhered, an excessive etching process in which the etching solution adheres to the entire main surface is avoided. Therefore, the etching process can be performed with the minimum necessary for roughening. As a result, the time required for supplying the finely divided etching solution and the time required for forming the corroded surface after the etching solution is attached can be shortened, and the working time can be shortened and thus the production efficiency can be improved. it can. In addition, by supplying finely divided etchant so that the untreated surface remains, the amount of etchant used can be reduced compared to immersion treatment, which improves not only the work cost but also the safety of the work environment. It is also possible to plan. Of course, if the surface is roughened by chemical treatment with an etchant, there is no concern that fine cracks such as latent scratches will be formed on the main surface of the glass substrate as in the case of surface roughening by polishing. It becomes possible to roughen the surface without reducing the strength of the glass substrate.

Moreover, the manufacturing method of the glass substrate which concerns on this invention may leave the untreated surface in the ratio of 10% or more and 90% or less by the area ratio with respect to the whole one main surface. In addition, the area ratio as used in the present specification was obtained by, for example, using VertScan 5300GL-A150-AC manufactured by Ryoko Co., Ltd. and taking an average value of values obtained by measuring an arbitrary position 10 times by bearing analysis.

  Thus, the etching is performed so that the area ratio of the untreated surface to the entire main surface is 90% or less, in other words, the ratio of the surface subjected to chemical treatment with the finely divided etching solution is 10% or more. By performing the treatment, it is possible to effectively reduce the contact area with the mating member that may come into contact with one main surface of the glass substrate in the manufacturing process of the glass substrate such as a plate, and to effectively suppress the peeling charge. Can be enjoyed. Further, by performing an etching process so that the untreated surface remains at 10% or more in the above-mentioned area ratio, new finely divided etching liquid adheres to the area where the finely divided etching liquid has adhered (multiple adhesion). The situation can be suppressed as much as possible, and the corroded surface as a region corroded by the etching solution can be formed evenly distributed without being biased.

  Moreover, the manufacturing method of the glass substrate which concerns on this invention may supply the etching liquid atomized with the center particle diameter of 1 micrometer or more and 100 micrometers or less to one main surface. In addition, the center particle diameter as used in this specification is what is called a 50% particle diameter, for example, measured by the laser diffraction method.

  Thus, by using the finely divided etching solution having a center particle diameter of 1 μm or more, an etching solution having a size (amount) necessary for corrosion can be attached to one main surface. Further, by setting the center particle size of the finely divided etching solution to 100 μm or less, an appropriate number of corroded surfaces can be distributed randomly on one main surface without being biased.

  Moreover, the manufacturing method of the glass substrate which concerns on this invention may supply the atomized etching liquid so that the supply range of the atomized etching liquid with respect to one main surface may not overlap.

  In this way, by defining the supply range of the finely divided etching solution, the finely divided etching solution can be adhered to one main surface without unevenness. Therefore, it is possible to stably form a form in which corroded surfaces are randomly distributed and untreated surfaces remain between these corroded surfaces.

  Further, in the method for producing a glass substrate according to the present invention, a nozzle capable of spraying the finely divided etching solution in a line shape is arranged on one main surface side of the glass substrate, and the nozzle is arranged on one main surface with respect to the glass substrate. The finely divided etching solution may be sprayed and supplied toward one main surface while being relatively moved in a predetermined direction along the surface.

  By injecting and supplying the finely divided etching solution, the line-like etching solution can be attached to one surface over the entire area of one main surface of the glass substrate without overlapping the supply range. Thereby, the corroded surface can be distributed randomly even on a large-area glass substrate by a simple operation, and a uniform roughening treatment can be performed.

  In the method for producing a glass substrate according to the present invention, the finely divided etching solution contains hydrofluoric acid, and the concentration of hydrofluoric acid in the etching solution is set to 0.1 mass% or more and 10 mass% or less. It may be a thing.

  By setting the composition and concentration of the etching solution in this way, for example, when the above etching process is incorporated into a production line, the etching process can be performed in accordance with the speed of the production line, and the roughening at that time can be performed. It becomes possible to carry out at a desired level.

  Moreover, the solution of the said subject is achieved also by the glass substrate which concerns on this invention. That is, this glass substrate is a glass substrate having two main surfaces, and one main surface of the two main surfaces exists between the unprocessed surface and the unprocessed surface, and is a plate of the glass substrate than the unprocessed surface. It is characterized by having a corroded surface that recedes to the center in the thickness direction.

  Thus, the glass substrate according to the present invention was made based on the knowledge of the inventor described above, as in the method for producing a glass substrate according to the present invention, and one main surface is an untreated surface, It has a corroded surface that recedes from the untreated surface to the center side in the plate thickness direction of the glass substrate. Thus, the presence of a corroded surface between untreated surfaces results in a roughened state of one main surface. Further, by forming the corroded surface in such a manner that the corroded surface exists between the untreated surfaces, one main surface can be uniformly roughened. Further, if the corrosion treatment (etching treatment) is performed so that the corrosion surface is distributed as described above, an excessive etching treatment in which an etching solution adheres to the entire area of one main surface is avoided, and the roughening is performed. Therefore, it can be done with the minimum necessary etching process. As a result, the time required for the etching process can be shortened, the working time can be shortened, and the production efficiency can be improved. In addition, if the corroded surface is formed so that there is an untreated surface, for example, the amount of etching solution used can be reduced compared to immersion treatment, which improves not only the work cost but also the safety of the work environment. It is also possible to plan. Of course, if the surface is roughened by a chemical treatment with an etchant, there is no concern that fine cracks such as latent scratches will be formed on the surface of the glass substrate as in the case of a surface roughening treatment by polishing. It becomes possible to roughen the surface without reducing the strength of the substrate.

  Moreover, the glass substrate which concerns on this invention may be 10% or more and 90% or less of the area ratio which occupies for the whole one main surface of an untreated surface.

  Thus, corrosion is performed so that the area ratio of the untreated surface to the whole of one main surface is 90% or less, in other words, the ratio of the surface subjected to chemical treatment with the finely divided etching solution is 10% or more. By forming the surface, it is possible to effectively reduce the contact area with the mating member that may come into contact with one of the main surfaces of the glass substrate in the glass substrate manufacturing process, such as a plate, and to suppress effective peeling charging. It is possible to enjoy the effect. Further, if the area ratio of the untreated surface is 10% or more, for example, the corroded surface can be formed in a properly dispersed state without unevenness by spraying and supplying finely divided etching solution.

  In the glass substrate according to the present invention, the height difference between the untreated surface and the corroded surface may be 1 nm or more and 120 nm or less.

  In view of the purpose of reducing peeling charge by reducing the contact area with a mating member such as a plate, if the height difference between the untreated surface and the corroded surface is at least 1 nm, the contact area with the mating member such as a plate It is possible to reduce the peeling electrification. Further, if the corroded surface is formed by an etching process or the like so that the height difference between the untreated surface and the corroded surface is 120 nm or less, the time required for forming the corroded surface by the etching process can be shortened. Therefore, it is possible to efficiently form a corroded surface, that is, to roughen the surface by incorporating an etching process into the production line.

  The glass substrate according to the present invention may have an untreated surface with an area ratio of 70% or more and 90% or less of the entire main surface, and the corroded surface may be dimple-shaped. In this case, the average value of the inner diameter dimension of the corroded surface having a dimple shape may be not less than 5 μm and not more than 1000 μm. Here, the inner diameter dimension means a circumscribed circle diameter in a plan view of a corroded surface having a dimple shape.

  Thus, if the area ratio of the untreated surface to the entire main surface is 70% or more and 90% or less, a large number of corroded surfaces can be formed in a dimple shape relatively stably. In other words, for example, when the etching solution is atomized and supplied to one main surface, the supply range of the etching solution can be reliably ensured by adjusting the supply mode of the etching solution so that the above-mentioned area ratio is obtained. The finely divided etching solution can be supplied in a randomly dispersed state. Therefore, a large number of corroded surfaces having a certain size can be formed uniformly without unevenness, whereby one main surface can be uniformly roughened. At this time, by forming the corroded surface so that the average inner diameter of the dimple-shaped corroded surface is within the above range, a large number of corroded surfaces are randomly distributed on one main surface. The state can be created stably.

  Alternatively, in the glass substrate according to the present invention, the area ratio of the untreated surface to the entire one main surface may be 10% or more and 30% or less, and the untreated surface may have an island shape. In this case, the glass substrate according to the present invention may have an average value of the outer diameter of the unprocessed surface having an island shape of 5 μm or more and 1000 μm or less. Here, the outer diameter dimension means a circumscribed circle diameter in a state in which an unprocessed surface having an island shape is viewed in a plan view.

  In this way, by setting the area ratio of the untreated surface to 10% or more and 30% or less, the untreated surface is formed into an island shape, and the untreated surface forming this island shape is formed in a state of being moderately dispersed without unevenness. can do. Thereby, one main surface can be made into the state roughened uniformly, reducing the contact area with counterpart members, such as a plate, as much as possible.

  As described above, according to the present invention, a large-area glass substrate is uniformly roughened without causing a reduction in strength, and the processing necessary for the roughening is performed in a short time, thereby producing Efficiency can be improved.

It is a side view of the etching process process of the glass substrate which concerns on one Embodiment of this invention. It is AA sectional drawing of the etching process shown in FIG. FIG. 3 is a view of the etching treatment process shown in FIG. It is a principal part expanded side view which shows the modification of the etching process shown in FIG. It is the C section enlarged view of one main surface of the glass substrate shown in FIG. It is DD sectional drawing of the principal part of one main surface of the glass substrate shown in FIG. It is a principal part enlarged view of one main surface of the glass substrate which concerns on other embodiment of this invention. It is EE sectional drawing of the principal part of one main surface of the glass substrate shown in FIG.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 is a side view of an etching process of a glass substrate G and an etching processing apparatus 10 used in this process according to an embodiment of the present invention. The etching processing apparatus 10 includes an etching liquid supply device 11 that supplies finely divided etching liquid E to one main surface Ga of the glass substrate G, and a predetermined direction of the glass substrate G with respect to the etching liquid supply apparatus 11. And a cleaning device 13 that supplies a cleaning solution W such as water to a region of the one main surface Ga of the glass substrate G to which the etching solution E is supplied.

  Here, the glass substrate G to be subjected to the etching treatment has, for example, the following composition and form.

Glass substrate G, for example, by mass% terms of _{oxide, SiO 2: 60~75%, Al} 2 O 3: 5~20%, B 2 O 3: 0~15%, MgO: 0~10%, CaO: 0 to 15%, SrO 0 to 10%, BaO 0 to 10% glass composition can be taken. At this time, it is also possible to adopt a glass composition that does not substantially contain an alkali metal oxide. Here, “substantially no alkali metal oxide” means that the content of the alkali metal oxide in the glass composition is 3000 ppm or less (preferably 1000 ppm or less).

  The arithmetic average roughness Ra of one main surface Ga (facing downward in FIG. 1) to be subjected to the etching process of the glass substrate G is set to 0.2 nm or less. Also, the arithmetic mean roughness Ra of the other main surface Gb (facing upward in FIG. 1) that is directed in the opposite direction in the thickness direction of one main surface Ga and the glass substrate G and that is not subject to etching processing is also It is set to 0.2 nm or less. If the surface roughness of one main surface Ga is smooth to the above-mentioned level, the adhesion mode of the finely divided etching solution E described later is stabilized. Moreover, since the other main surface Gb is a main surface on the side where various elements, electrode wires, electronic circuits, etc. are formed, the surface roughness (arithmetic average roughness Ra) is set to the above-mentioned range. The above-described elements, electronic circuits, and the like can be formed with high accuracy.

The area of one main surface Ga of the glass substrate G (that is, the area of the other main surface Gb) is set to, for example, 0.2 m ² or more, preferably 0.5 m ² or more, more preferably 0.6 m ² or more. It is set, and particularly preferably set to 1.0 m ² or more. The larger the glass substrate G is, the easier it can be applied to various purposes, and the production efficiency is improved by multi-chamfering. On the other hand, the larger the area of the glass substrate G, the easier it is to store static electricity and easily cause electrification, and the glass substrate G is more likely to be damaged in subsequent lift-up processes when stuck to the plate by adsorption. Although problems are likely to occur, by applying the present invention described later, these problems can be solved and the advantage of increasing the area of the glass substrate G can be exhibited.

  The thickness dimension of the glass substrate G is, for example, set to 1.0 mm or less, preferably set to 0.6 mm or less, more preferably set to 0.5 mm or less, and particularly preferably set to 0.4 mm or less. The smaller the thickness dimension of the glass substrate G, the more likely to cause problems such as the glass substrate G being easily damaged in subsequent steps such as lift-up when adhering to a plate or the like by suction. By applying, these problems can be solved and the glass substrate G can be applied to a wide range of uses.

  The glass substrate G having the above composition and form is formed, for example, by a down draw method, and preferably formed by an overflow down draw method. By molding by this method, the glass substrate G having a large area and good surface accuracy (in other words, the arithmetic average roughness Ra shows a value in the above range) can be efficiently molded. In this case, the main surfaces Ga and Gb of the glass substrate G are both as-formed surfaces (also referred to as molding surfaces and fire-making surfaces). Of course, the above description does not deny the formation of the glass substrate G by a forming means other than the downdraw method. For example, as long as the cleanliness of the priority guarantee surface by molten tin can be ensured, the float method is adopted. Is also possible.

  Hereinafter, each element of the etching processing apparatus 10 will be described in detail.

  As shown in FIG. 1, the etchant supply device 11 is disposed on the one main surface Ga side of the glass substrate G. The etching solution supply device 11 has a nozzle 14 for spraying and supplying the etching solution E in a fine particle state, and has an arrangement mode in which the nozzle 14 is directed to one main surface Ga.

  For example, as shown in FIG. 2, the nozzles 14 are arranged in a state where a plurality of nozzles are arranged in a line. As shown in FIG. 3, each of these nozzles 14 is designed to spray and supply finely divided etching solution E in a line shape. For example, as shown in FIG. It spreads as it goes on (in other words, spreads like a fan). Therefore, as shown in FIG. 2, when the supply ranges of the finely divided etching liquid E with respect to one main surface Ga do not overlap each other, the spray width of each nozzle 14, from the tip of the nozzle 14 to one main surface Ga The distance d and the arrangement interval of the nozzles 14 are preferably set as appropriate.

  Here, as the finely divided etching solution E, for example, one containing a fluorine-containing component such as acidic ammonium fluoride or hydrofluoric acid can be used. For example, when the etching solution containing hydrofluoric acid is used as the finely divided etching solution E, the concentration is set to, for example, 0.1 mass% or more and 10 mass% or less. The central particle size of the etching solution E is set to 1 μm or more and 100 μm or less, preferably 1.5 μm or more and 30 μm or less, more preferably 2 μm or more and 20 μm or less. As an example of the above-described etching solution containing hydrofluoric acid, for example, a solution containing 46% hydrogen fluoride can be given.

  A known nozzle can be used as the nozzle 14 having the above-described configuration. Among them, spray nozzles such as a one-fluid type, a two-fluid type, an ultrasonic type, and the same fluid collision type can be suitably used.

  In this embodiment, the moving device 12 is a transfer device for the glass substrate G, and includes a plurality of rollers 15 that support one main surface Ga of the glass substrate G, for example, as shown in FIG. The conveyance direction f of the glass substrate G by the plurality of rollers 15 is orthogonal to the direction along the line of finely divided etching solution E sprayed and supplied from, for example, the nozzle 14 (see FIG. 3). ing.

  The cleaning device 13 is disposed on the one main surface Ga side of the glass substrate G and on the downstream side (left side in FIG. 1) in the transport direction f of the glass substrate G by the moving device 12. The corrosion time of one main surface Ga is determined after the finely divided etching liquid E adheres to one main surface Ga of the glass substrate G and before the cleaning liquid W reaches this one main surface Ga. In consideration of the above, it is preferable to set the position of the cleaning device 13 (position in the transport direction f).

As shown in FIG. 4, so that the supply position P _E of the etching solution E for one main surface Ga of the glass substrate G is higher than the supply position P _W of the cleaning liquid W to the one main surface Ga, etching It is also possible to set the supply conditions of the liquid E and the cleaning liquid W (in FIG. 4, the upper direction in FIG. 4 coincides with the vertical upper direction). By setting the supply position P _W of the supply position P _E and the cleaning solution W in this manner the etchant E, one of the cleaning liquid W supplied toward the main surface Ga of the glass substrate G from the cleaning device 13, the etching solution The situation of moving toward the supply position PE of _E can be prevented. In this case, since there is no possibility that the etching solution E attached to one main surface Ga of the glass substrate G is diluted, a desired etching effect can be stably obtained.

From the viewpoint of maintaining the shape of the plurality of rollers 15 installed below the glass substrate G when the finely divided etching solution E is attached, from the supply position P _E of the etching solution _E (see FIG. 4). Also, the rollers 15 (15a, 15b) are disposed at a position avoiding the downstream side in the transport direction f and avoiding the upstream side in the transport direction f from the supply position P _{W of the} cleaning liquid W (see FIG. 4). Is good. In other words, the first and second rollers 15a adjacent in the conveying direction f of the glass substrate G, between the 15b, good to set the supply position P _W of the supply position P _E and the cleaning solution W in the etching liquid E . Thus, by providing the first roller 15a closest to the supply position P _E of the etching liquid E and the second roller 15b closest to the supply position P _W of the cleaning liquid W, the fine particle etching liquid is disposed. After E adheres to one main surface Ga, it is possible to reliably avoid the situation of touching the roller 15 until it is washed away with the cleaning liquid W. Therefore, it is possible to perform a desired etching process while maintaining as much as possible the shape of the etching solution E when attached to one main surface Ga.

  Hereinafter, an example of the roughening process of the glass substrate G using the etching processing apparatus 10 having the above configuration will be described. Note that the following description applies not only to the process shown in FIG. 1 but also to the process shown in FIG. 4, for example.

  First, as shown in FIG. 1, the moving device 12 transports a plurality of glass substrates G along a predetermined transport direction f, and the nozzle 14 of the etching solution supply device 11 disposed on one main surface Ga side of the glass substrate G. The finely divided etching solution E is jetted and supplied. At this time, as shown in FIG. 3, the finely divided etching solution E is sprayed and supplied in a line shape, and the finely divided etching solution E is spread over the entire width direction of the glass substrate G (direction perpendicular to both the transport direction f and the thickness direction). Liquid E is supplied. Therefore, by continuously moving the glass substrate G along the transport direction f by the moving device 12, the finely divided etching solution E is sprayed and supplied toward the entire area of the one main surface Ga of the glass substrate G.

  After spraying and supplying the finely divided etching liquid E toward one main surface Ga, the cleaning liquid W such as water is supplied from the cleaning device 13 located on the downstream side in the transport direction f of the glass substrate G on one main surface. The etching liquid E that adheres to one main surface Ga is washed away by supplying to Ga. The adhesion time of the finely divided etching solution E, that is, the etching time for one main surface Ga is set to, for example, 1 second or more and 1 minute or less, preferably 5 seconds or more and 20 seconds or less.

  FIG. 5 is an enlarged view of an essential part showing an example of a region subjected to an etching process in response to the spray supply of the already finely divided etching solution E in one main surface Ga of the glass substrate G. As shown in FIG. 5, a number of corroded surfaces 16 are formed on one main surface Ga as a result of adhesion of finely divided etching solution E, and an etching process is performed between these corroded surfaces 16. The untreated surface 17 (molded surface in the present embodiment) constituting the immediately preceding main surface Ga remains. Here, the area ratio of the untreated surface 17 to the entire one main surface Ga is set to 10% or more and 90% or less. In the present embodiment, an enlarged view of the main part of one main surface Ga when the etching process is performed so that the area ratio of the unprocessed surface 17 to the entire one main surface Ga is approximately 80% is illustrated in FIG. ing. The area ratio of the unprocessed surface 17 described above can be adjusted as appropriate depending on, for example, the distance d between the tip of the nozzle 14 of the etching solution supply device 11 and the glass substrate G, the moving speed of the glass substrate G, and the like.

  In this case, the corroded surface 16 generally has a dimple shape, and the average value of the inner diameter dimension m is not less than 5 μm and not more than 1000 μm. Further, the height difference h (see FIG. 6) between the corroded surface 16 and the untreated surface 17 is, for example, 1 nm or more and 120 nm or less. Thus, the corroded surface 16 obtained by the etching process according to the present invention has a wide and shallow shape as a whole.

  Thus, according to the manufacturing method of the glass substrate G which concerns on this invention, as shown in FIG. 5, the minute corrosion surface 16 distributed at random can be formed in one main surface Ga. Therefore, the uniform roughening treatment with the finely divided etching solution E can be applied to the entire area of one main surface Ga. In addition, in the present invention, the etching solution E is supplied so that the unprocessed surface 17 remains between the regions to which the etching solution E is attached, so that the etching solution E is attached to the entire area of one main surface Ga. Therefore, it is possible to avoid the excessive etching process and perform the minimum etching process necessary for roughening. As a result, it is possible to shorten the time required to supply the finely divided etching solution E and the time required to form the corroded surface 16 after the etching solution E adheres, thereby shortening the working time and thus improving the production efficiency. Can be planned. In addition, by supplying the etching solution E that has been finely divided so that the untreated surface 17 remains, the amount of the etching solution E used can be reduced as compared with the dipping treatment. It is also possible to improve the performance.

In the present embodiment, as shown in FIG. 3, the finely divided etching liquid E is sprayed and supplied in a line shape over the entire width direction of one main surface Ga, and the direction perpendicular to the width direction (transport direction f) In other words, the glass substrate G is moved so that the etching process according to the present invention can be performed over the entire area of one main surface Ga by a single scan in the direction along the conveying direction f of the nozzle 14. This makes it possible to achieve a more uniform roughening and further improve the working efficiency.

  Further, in the present embodiment, as shown in FIG. 1 and the like, the glass substrate G is moved in a horizontal posture, and the fine particles are formed from below the glass substrate G toward one main surface Ga directed downward of the glass substrate G. The etching solution E was sprayed and supplied. By doing in this way, the situation where the etching liquid E adhering to one main surface Ga wraps around the other main surface Gb which becomes a priority guarantee surface can be prevented as much as possible. Further, when the finely divided etching solution E is supplied from below, it is less likely that the fine particles of the etching solution E adhering to one main surface Ga move and overlap along the one main surface Ga. It is easy to disperse and supply the etching solution E evenly.

  As mentioned above, although one Embodiment of this invention was described, the manufacturing method of the glass substrate G which concerns on this invention, or the glass substrate G is not limited to the said embodiment, Various forms are within the scope of the present invention. It is possible to take

  For example, in the above embodiment, the glass substrate G is conveyed in a horizontal posture, and the finely divided etching solution E is supplied to the one main surface Ga directed downward from the glass substrate G. (Refer to FIG. 1) Of course, it is possible to adopt other supply modes. For example, although not shown in the drawing, the etching liquid E finely divided from the upper side of the glass substrate G may be supplied with one main surface Ga to be an etching process on the upper side, or the glass substrate G is placed vertically. The finely divided etching solution E may be supplied toward one main surface Ga oriented in the horizontal direction.

  In the above embodiment, the plurality of nozzles 14 are arranged in a line (see FIG. 2), and the finely divided etching solution E sprayed and supplied from each nozzle 14 is formed in a single line ( (See FIG. 3) The case is illustrated, but it is of course possible to adopt other supply modes. For example, although not shown in the figure, a nozzle that can spray and supply finely divided etching liquid E from a slit-shaped injection port is used and does not diffuse from the tip of the nozzle to the glass substrate G (the injection range because the etching liquid E goes straight). The etching solution E may be sprayed and supplied so as to be constant in the width direction. Of course, it is also possible to spray and supply the finely divided etching solution E using a nozzle having a cross-sectional shape other than the line shape.

  Moreover, in the said embodiment, the glass substrate G is moved with the moving apparatus 12 comprised by the some roller 15, and the finely divided etching liquid E is supplied from the etching liquid supply apparatus 11 of the state fixed to the predetermined position. However, of course, with the glass substrate G fixed at a predetermined position, for example, the nozzle 14 of the etching liquid supply device 11 is moved (scanned) in a predetermined direction, and the etching liquid is atomized on one surface Ga. E may be supplied by injection.

  Moreover, in the said embodiment, the case where the area ratio with respect to one main surface Ga whole of the untreated surface 17 was made larger than the area ratio with respect to one main surface Ga whole of the corrosion surface 16 was illustrated (refer FIG. 5). Of course, other forms are possible.

  FIG. 7 is an enlarged view of a main part of a region subjected to an etching process in response to an injection supply of an already finely divided etching solution E in one main surface Ga of a glass substrate G according to another embodiment of the present invention. is there. As shown in FIG. 7, the corroded surface 16 according to the present embodiment is formed over a wider area of one main surface Ga than in the case shown in FIG. Further, between the corroded surfaces 16, an untreated surface 17 (molded surface in the present embodiment) having an island shape remains in a state of being dispersed on one main surface Ga. In this case, the area ratio of the untreated surface 17 to the entire one main surface Ga is set to 10% or more and 30% or less. In the present embodiment, FIG. 7 illustrates one main surface Ga when the etching process is performed so that the area ratio of the unprocessed surface 17 to the entire one main surface Ga is approximately 20%.

  In this case, the unprocessed surface 17 generally has an island shape, and the average value of the outer diameter dimension n is not less than 5 μm and not more than 1000 μm. Further, the height difference h (see FIG. 8) between the corroded surface 16 and the untreated surface 17 is, for example, 1 nm or more and 120 nm or less.

  Thus, even when the area ratio of the untreated surface 17 to the entire one main surface Ga is smaller than the area ratio of the corroded surface 16 to the entire main surface Ga (see FIG. 7), As long as the surface 16 and the untreated surface 17 exist, the glass substrate G according to the present invention can take any form. In any of the above cases, one main surface Ga of the glass substrate G is uniformly roughened without causing a reduction in strength, and the processing necessary for the roughening is performed in a short time, thereby producing The efficiency can be improved, and the high-quality glass substrate G can be provided at a low cost.

DESCRIPTION OF SYMBOLS 10 Etching processing apparatus 11 Etching liquid supply apparatus 12 Moving apparatus 13 Cleaning apparatus 14 Nozzle 15, 15a, 15b Roller 16 Corrosion surface 17 Untreated surface G Glass substrate Ga One main surface E Fine particle etching liquid W Cleaning liquid

Claims (13)

When roughening the surface of one of the two main surfaces of the glass substrate by etching,
A finely divided etching solution is supplied to the one main surface, and the one main surface immediately before supplying the finely divided etching solution is provided between the regions where the finely divided etching solution is attached. A method for producing a glass substrate, characterized in that a treated surface remains.   The method for producing a glass substrate according to claim 1, wherein the untreated surface is left in a ratio of 10% or more and 90% or less in an area ratio with respect to the entire one main surface.   The method for producing a glass substrate according to claim 1 or 2, wherein the finely divided etching solution having a center particle diameter of 1 µm or more and 100 µm or less is supplied to the one main surface.   The manufacturing method of the glass substrate in any one of Claims 1-3 which supply the said micronized etching liquid so that the supply range of the said micronized etching liquid with respect to said one main surface may not overlap. A nozzle capable of spraying the finely divided etching solution in a line shape is disposed on the one main surface side of the glass substrate,
5. The finely divided etching solution is sprayed and supplied toward the one main surface while the nozzle is moved relative to the glass substrate in a predetermined direction along the one main surface. The manufacturing method of the glass substrate in any one of.   The finely divided etching solution contains hydrofluoric acid, and the concentration of the hydrofluoric acid in the etching solution is set to 0.1% by mass or more and 10% by mass or less. The manufacturing method of the glass substrate of description. In a glass substrate having two main surfaces,
One main surface of the two main surfaces is an untreated surface, and a corroded surface that exists between the untreated surfaces and recedes from the untreated surface to the center side in the plate thickness direction of the glass substrate. A glass substrate characterized by comprising:   The glass substrate according to claim 7, wherein an area ratio of the untreated surface to the entire one main surface is 10% or more and 90% or less.   The glass substrate according to claim 7 or 8, wherein a difference in height between the untreated surface and the corroded surface is 1 nm or more and 120 nm or less.   The glass substrate according to any one of claims 7 to 9, wherein an area ratio of the untreated surface to the entire one main surface is 70% or more and 90% or less, and the corroded surface has a dimple shape.   11. The glass substrate according to claim 10, wherein an average value of an inner diameter dimension of the corroded surface having the dimple shape is 5 μm or more and 1000 μm or less.   The glass substrate according to any one of claims 7 to 9, wherein an area ratio of the untreated surface to the entire one main surface is 10% or more and 30% or less, and the untreated surface has an island shape.   The glass substrate according to claim 12, wherein an average value of outer diameter dimensions of the untreated surface that forms the island shape is 5 μm or more and 1000 μm or less.

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