JP6585984B2 - Display glass substrate manufacturing method, display glass substrate manufacturing apparatus - Google Patents

Description

  The present invention relates to a method for manufacturing a glass substrate for a display including a surface treatment process for roughening one of the main surfaces of a thin glass plate, and a manufacturing apparatus therefor.

  In the manufacture of a flat panel display using a liquid crystal display panel, a plasma display panel, an organic EL display panel or the like used as a display panel, a finer thin film pattern is formed on a thin glass substrate.

  The display panel used in these flat panel displays is manufactured through a processing process such as conveyance, film formation, photolithography, etching, doping, or wiring after putting a glass substrate into the production line. In each processing step, the panel including the glass substrate is placed in an environment in which it is easily charged due to various factors. For example, when putting a glass substrate into a production line, the interleaving paper is peeled and removed from a plurality of glass substrates stacked with the interleaving paper interposed therebetween, and the glass substrates are taken out one by one. At this time, the glass substrate is easily charged when the interleaf is removed. In addition, when a semiconductor manufacturing apparatus is used for film formation or the like, film formation is performed by placing a glass substrate on a mounting table. At this time, the glass substrate is likely to be charged by airflow, contact charging, or peeling charging.

  Such charging causes various problems. For example, when a TFT (Thin Film Transistor) and a wiring pattern are formed on a glass substrate, foreign matters such as dust and dust adhere to the glass substrate and the wiring pattern due to charging, and the wiring pattern is lost or peeled off or accumulated. In other words, the TFT is destroyed by the discharge of the charges. In addition, the glass substrate may stick to the mounting table due to electrification, and the glass substrate may break when it is peeled off from the mounting table. Therefore, it is preferable that the glass substrate is not charged as much as possible.

  In particular, the surface of the thin glass produced by the fusion method or the downdraw method is much smoother than the thin glass produced by the float method, and therefore, charging problems are likely to occur. For this reason, it is preferable to perform some treatment for preventing charging on the main surface of the thin glass substrate obtained by the fusion method or the downdraw method. As a general method, one of the main surfaces of the thin glass substrate is roughened by a chemical method, and charging of the thin glass substrate can be prevented by appropriate roughening. In addition, a method is known in which a charged glass substrate is neutralized using an ionizer (Patent Document 1). There is also known an exposure apparatus that reduces the amount of electrostatic charge on a processing substrate generated in a process of placing, attaching, and removing a processing substrate on which a photosensitive layer or the like is formed on a stage (Patent Document 2).

JP 2009-64950 A JP 2007-322630 A

  In a thin glass substrate for flat panel displays, the main surface of the main surface on which the TFT and wiring pattern are not formed (hereinafter referred to as the first surface) is roughened by chemical treatment or the like to prevent charging. To do. The main surface (hereinafter referred to as the second surface) on which the TFT and the wiring pattern are formed is not treated, and dirt and foreign matter must be removed.

  According to the surface treatment method using a porous material having a continuous pore structure such as a sponge, and applying an etching solution only to the first surface of the thin glass with a roughening roller having a porous material holding an etching solution on the outer peripheral portion. A plurality of glass substrates can be continuously roughened.

  In such a surface treatment step, the glass substrate is transported while applying the etching solution to the first surface of the glass substrate by the roughening roller holding the etching solution, but the coating of the etching solution is not always constant.

  If the amount of the etching solution retained (absorbed amount) in the porous material of the roughening roller is too small and the coating amount on the glass substrate decreases, uneven coating of the glass substrate occurs. On the other hand, if the amount of the etching solution retained (the amount of liquid absorption) is too large, the etching solution may wrap around the second surface of the glass substrate where dirt and foreign matter are restricted on the end surface side of the glass substrate. If the coating of the etching solution on the glass substrate varies greatly under continuous processing, the quality of the surface shape due to the roughening cannot be achieved, and the efficiency of mass production is reduced.

  Accordingly, the present invention provides an application of an etching solution to a glass substrate in a surface treatment in which a plurality of glass substrates are continuously roughened using a roughening roller having a porous material having a continuous pore structure at an outer peripheral portion. Surface treatment that can control the amount to be almost constant, suppress the wrapping of the etchant to the second surface where foreign matter and dirt are restricted, and can produce high-quality thin glass by roughening it in a continuous process for mass production. A method for manufacturing a glass substrate for display and a glass substrate manufacturing apparatus for display, including the method and its processing apparatus, are provided.

One aspect of the present invention is a method for producing a glass substrate for a display including a surface treatment step of continuously roughening the first surface of the main surface of the glass substrate,
In the surface treatment step, it is contacted with the glass substrate into a plurality of roughened roller having a porous material which holds the etchant to the outer peripheral portion, and conveyance husk is supported to contact the roughened roller to a glass substrate in the between the roughened roller and glass base plate, the first surface of the glass substrate such that the porous material is by supplying a part of the etchant to retain forming the wetted membrane layer etchant Apply the etchant on top,
The wetted film layer formed by applying the etchant is compared with a predetermined reference wetted film layer, and the wetted film layer of the wetted film formed by applying the etchant is in the direction of the rotation axis of the roughening roller. The coating amount of the etching solution is adjusted so that the average value of the liquid widths at a plurality of locations along the reference wetted film layer is approximately equal to the liquid width of the reference wetted film layer, and the first surface of the main surface of the glass substrate is roughened. Turn into.

  In the plurality of roughening rollers, it is preferable that each coating amount is adjusted to be substantially the same amount.

  It is preferable that the application amount is adjusted using a squeeze roller.

  It is preferable that the porous material has a continuous pore structure having a pore diameter of 10 μm to 100 μm and a porosity of 80% or more.

  The arithmetic average roughness Ra of the first surface after the surface treatment step is preferably 0.40 nm or more.

One aspect of the present invention is a glass substrate manufacturing apparatus for a display including a surface treatment apparatus that continuously roughens the first surface of the main surface of the glass substrate,
The surface treatment apparatus is such that a glass substrate is brought into contact with and supported by a plurality of roughening rollers having a porous material holding an etching solution at an outer peripheral portion, and the roughening roller is in contact with the glass substrate. Etching the first surface of the glass substrate so as to form a wetted film layer of the etching solution by supplying a part of the etching solution held by the porous material between the roughening roller and the glass substrate. An etching apparatus for applying a liquid;
Monitoring means for reflecting the form of the wetted film layer formed by application of an etching solution so that it can be compared with a predetermined reference wetted film layer;
The liquid width of the reference wetted film layer is approximately equal to the average value of the liquid widths at a plurality of locations along the rotation axis direction of the roughening roller of the wetted film layer formed by applying the etching liquid. And an adjusting means for adjusting the coating amount of the etching solution.

  In the plurality of roughening rollers, it is preferable that each coating amount is adjusted to be substantially the same amount.

  It is preferable that the adjusting means is a squeeze roller.

  It is preferable that the porous material is made of a porous material having a continuous pore structure having a pore diameter of 10 μm to 100 μm and a porosity of 80% or more.

  According to the present invention, in the surface treatment for continuously roughening the first surface of the main surface of the glass substrate, the amount of the etchant applied to the glass substrate is controlled to be constant, and dirt and foreign matter are restricted. In this way, it is possible to suppress the wrapping of the etching solution to the second surface and to produce a high-quality high-definition thin glass plate that is roughened by continuous processing and mass-produced.

It is a flowchart which shows the outline | summary of an example of the manufacture process of the glass substrate for displays of this embodiment. It is a schematic diagram explaining an example of the glass substrate surface treatment apparatus used at the surface treatment process of this embodiment. It is a figure explaining an etching wetted film layer. It is a schematic top view of the roughening roller of the glass substrate surface treatment apparatus of this embodiment. It is a figure explaining the height adjustment of a contact member. It is a figure explaining the height adjustment of a roughening roller. It is an image figure about a reference | standard wet contact film layer.

  Hereinafter, the manufacturing method and glass substrate surface treatment apparatus of the glass substrate of this embodiment are demonstrated. FIG. 1 is a flowchart showing an outline of the manufacturing process of the glass substrate 100. In FIG. 1, the outline of a process until a glass substrate will be in the state shipped from the state which melts a raw material to a customer etc. is shown.

(1) Manufacturing method of glass substrate Hereinafter, the manufacturing apparatus of the glass substrate of this invention and the manufacturing method of a glass substrate are demonstrated.
Although the glass substrate manufactured in this embodiment is not particularly limited, for example, the vertical dimension and the horizontal dimension are 500 mm to 3500 mm, 1500 mm to 3500 mm, 1800 to 3500 mm, 2000 mm to 3500 mm, etc., and 2000 mm to 3500 mm. Preferably there is.
As for the thickness of a glass substrate, 0.1-1.1 (mm) is mentioned, for example, More preferably, it is a very thin rectangular-shaped board of 0.75 mm or less, for example, 0.55 mm or less, Furthermore, 0.00. A thickness of 45 mm or less is more preferable. As a lower limit of the thickness of a glass substrate, 0.15 mm or more is preferable and 0.25 mm or more is more preferable.

First, the melted glass is formed into a sheet glass, which is a strip glass having a predetermined thickness, by a known method such as a fusion method or a float method (step S1).
Next, the formed sheet glass is sampled on a glass substrate which is a base plate having a predetermined length (step S2). After step 2, the glass substrate obtained by the sampling plate is guided and transported to the heat treatment step while being pinched and held by the transport mechanism, and then the heat treatment step may be performed on the transported glass substrate. .

  The glass substrate after the heat treatment is conveyed to a cutting process, and is cut into a product size to obtain a glass substrate (step S3). The obtained glass substrate is subjected to end face processing including end face grinding, polishing, and corner cutting (step S4). First cleaning for cleaning the glass substrate in order to remove fine foreign matters and dirt on the glass surface of the glass substrate after the end face processing (step S5).

  The surface treatment S6 (roughening step Pr1 and rinsing step Pr2) of this embodiment is performed after the cleaning step S5 immediately after the end face processing. Details of the surface treatment process of this embodiment will be described later.

  After the surface treatment step S7, the second post-cleaning S8 is performed, and thereafter the cleaned glass substrate is optically inspected for scratches, dust, dirt, or scratches including optical defects (step S8). The glass substrate having the quality matched by the inspection is loaded on the pallet and packed as a laminated body alternately laminated with paper protecting the glass substrate (step S9). The packed glass substrate is shipped to a supplier.

As such a glass substrate, the glass substrate of the following glass compositions is illustrated. That is, the raw material of molten glass is prepared so that the glass substrate of the following glass compositions is manufactured.
SiO ₂ 55~80 mol%,
Al ₂ O ₃ 8-20 mol%,
B ₂ O ₃ 0 to 12 mol%,
RO 0 to 17 mol% (RO is the total amount of MgO, CaO, SrO and BaO).

SiO ₂ is preferably 60 to 75 mol%, and more preferably 63 to 72 mol%, from the viewpoint of reducing the heat shrinkage rate.
Among RO, it is preferable that MgO is 0-10 mol%, CaO is 0-15 mol%, SrO is 0-10%, and BaO is 0-10%.

Further, at least SiO ₂ , Al ₂ O ₃ , B ₂ O ₃ , and RO are included, and the molar ratio ((2 × SiO ₂ ) + Al ₂ O ₃ ) / ((2 × B ₂ O ₃ ) + RO) is 4. The glass which is 5 or more may be sufficient. In addition, it is preferable that at least one of MgO, CaO, SrO, and BaO is included, and the molar ratio (BaO + SrO) / RO is 0.1 or more.

The total content of 2-fold and mol% of RO for the content of mol% of B ₂ O ₃ is 30 mol% or less, it is preferred that preferably 10 to 30 mol%.
Moreover, 0 mol% or more and 0.4 mol% or less may be sufficient as the content rate of the alkali metal oxide in the glass substrate of the said glass composition.
Further, it contains 0.05 to 1.5 mol% of metal oxides (tin oxide and iron oxide) whose valence fluctuates in the glass, and substantially contains As ₂ O ₃ , Sb ₂ O ₃ and PbO. It is not essential but optional.

  The glass substrate manufactured by this embodiment is a glass substrate for flat panel displays, or a glass substrate for curved panel displays, and is suitable, for example, as a glass substrate for liquid crystal displays or a glass substrate for organic EL displays. Furthermore, the glass substrate manufactured in the present embodiment is particularly suitable as a glass substrate for LTPS (Low-temperature polysilicon), IGZO (Indium-Gallium-Zinc-Oxide), TFT display used for high-definition displays.

  As a method for forming sheet glass from molten glass in this embodiment, a float method, a fusion method, or the like is used. However, a method for manufacturing a glass substrate including offline heat treatment of the glass substrate in this embodiment is a fusion method (overdown). The draw method is suitable for the fusion method because it is difficult to lengthen the slow cooling device on the production line. The thermal shrinkage rate of the glass substrate of this embodiment is 50 ppm or less, preferably 40 ppm or less, more preferably 30 ppm or less, and even more preferably 20 ppm or less. The range of the heat shrinkage rate of the glass substrate before reducing the heat shrinkage rate is preferably 10 ppm to 40 ppm.

(2) Surface treatment step S6
(2-1) Surface treatment method and surface treatment apparatus The surface treatment process of this embodiment will be described in detail. The surface treatment process of this embodiment includes a roughening process (Pr1) in which one surface (first surface) of the main surface of the glass substrate is surface-treated with an etching solution, and etching of the roughened first surface. A rinsing step (Pr2) is also included in which the liquid is washed again with washing water and then washed again, and the second surface that has not been roughened is washed with pure water. Details of the surface treatment S5 will be described later.

  In the surface treatment step S7, only one surface of the main surface of the glass substrate is roughened. The main surface to be roughened is the main surface opposite to the surface on which the TFT and wiring pattern are formed, and no surface treatment (roughening) is performed on the other main surface.

  By performing the roughening treatment, various problems due to charging as described below can be prevented. For example, when a TFT (Thin Film Transistor) and a wiring pattern are formed on a glass substrate, foreign matters such as dust and dust adhere to the glass substrate and the wiring pattern due to charging, and the wiring pattern is lost or peeled off or accumulated. There is a problem that the TFT is destroyed due to the discharge of the electric charge. In addition, the glass substrate may stick to the mounting table due to electrification, and the glass substrate may break when it is peeled off from the mounting table. In order to prevent these problems caused by charging, it is preferable that one side of the main surface of the glass substrate is roughened to prevent charging as much as possible, especially in the fusion method and the overflow downdraw method. The molded glass sheet is preferably subjected to a roughening treatment.

  FIG. 2 is a schematic diagram illustrating an example of the glass substrate surface treatment apparatus 1 that performs the surface treatment step S7. In the apparatus of the present embodiment (FIG. 2), a method is adopted in which the glass substrate is transported on a roughening roller in a horizontal state to be roughened.

  FIG. 3 is a schematic top view of the roughening roller used in the glass substrate surface treatment apparatus 1. FIG. 4 is a diagram for explaining the roughening of the glass substrate by the roughening roller.

The surface treatment process of the present embodiment will be described with reference to FIG. 2, but the glass substrate surface treatment apparatus 1 (FIGS. 2 to 4) is an example, and the surface treatment process S <b> 6 is the glass substrate surface treatment apparatus 1. It can carry out using the apparatus of composition other than.
The glass substrate surface treatment apparatus 1 roughens one main surface while transporting the glass substrate in the transport direction (specifically, the direction shown by the arrow A1 in FIGS. 2 to 4). Here, the glass substrate surface treatment apparatus 1 makes the first surface 100a a predetermined surface roughness by roughening the first surface 100a (see FIG. 2) which is one main surface of the glass substrate 100. ing. Here, the first surface 100a is a surface on which TFT elements and wiring patterns which are thin films are not formed in the manufacturing process of the display device.

<Apparatus configuration of roughening process Pr1>
As shown in FIGS. 2 to 4, the glass substrate surface treatment apparatus 1 is mainly a roughening step (Pr1) in which a surface treatment is performed, and a rough material having a porous material holding an etchant on an outer peripheral portion including a peripheral surface. An etching apparatus for applying an etching solution to the first surface of the glass substrate so as to form a wetted film layer of the etching solution between the surface roller and the glass substrate;
Monitoring means for displaying the form of the wetted film layer so that it can be compared with a predetermined wetted film layer;
Adjusting means for adjusting the coating amount of the etching solution so that the reference wetted film layer and the wetted film layer have substantially the same form.
Furthermore, it is preferable that the adjusting means is a squeeze roller.
Furthermore, it is preferable that the porous material has a continuous pore structure having a pore diameter of 10 μm to 100 μm and a porosity of 80% or more.

  Further, the roughening step (Pr1) may be further provided with a temperature control means that is surrounded by the housing 2 and that manages the temperature of the space in the housing. In the roughening step, the etching solution in the etching tank 11 is vaporized and stays in the air in the housing. Therefore, the air in the housing is appropriately ventilated and is derived from the etching solution contained in the discharged air in the housing. It is preferable to provide a recovery mechanism for recovering the chemical substances.

A. Embodiment 1. FIG. Surface treatment device including a device for making the coating amount of the etching solution constant The display device of the present embodiment is provided between a roughening roller and a glass substrate having a porous material holding an etching solution in an outer peripheral portion including a peripheral surface. And an etching apparatus for applying an etching solution to the first surface of the glass substrate so as to form a wetted film layer of the etching solution;
Monitoring means for monitoring that the size of the liquid contact film layer seen through from the surface direction of the glass substrate not coated with the etchant is substantially constant compared to a predetermined reference liquid contact film layer; At least.
Furthermore, it is preferable that the etching apparatus includes a squeezing roller that adjusts the coating amount of the roughening roller based on the result monitored by the monitoring unit.
Further, in the etching apparatus, a plurality of the roughening roller and the squeezing roller are provided, and based on the result measured by the monitoring means, the coating amount of each of the roughening rollers is substantially the same amount, It is preferable to further include a control mechanism for adjusting each squeezing roller.
The roughening roller is preferably a porous material having a continuous pore structure having a pore diameter of 10 μm to 100 μm and a porosity of 80% or more.

  An etching apparatus in the display device 1 (FIG. 2) of the present embodiment will be described.

  In the roughening step (Pr1), an etchant tank 16 for adjusting and storing the etchant may be further provided. The etching solution is supplied to the etching tank 11 and circulated by the etching solution tank 16. Further, it is possible to adjust the etching solution while replenishing the etching solution tank 16 with hydrofluoric acid so as to maintain the etching rate in the roughening treatment, and circulate the adjusted etching solution to the etching tank 11 for use. it can. Between the etching tank 11 and the etchant tank, pipes 15a and 15b are provided so that the etchant MS can be circulated.

  The etching solution tank 16 is further connected to a plurality of tanks that supply (acid component of the etching solution) for adjusting the etching solution. For example, a hydrofluoric acid tank that supplies hydrofluoric acid and a phosphoric acid tank that supplies phosphoric acid are connected to the etchant tank 16, and a constituent material (acid component) of the etchant is supplied from these tanks to provide an etchant. The etching solution is adjusted in the tank 16. The installation of a plurality of tanks for supplying etching components is determined according to the type of constituent material. For example, when the etching solution further contains hydrochloric acid, a hydrochloric acid tank is further connected to the etching solution tank 16.

  The etching tank 11 stores an etching solution MS as a processing fluid for processing the surface of the glass substrate 100. In the present embodiment, an etching solution MS that essentially contains hydrofluoric acid and phosphoric acid or an etching solution MS that contains hydrochloric acid in addition to hydrofluoric acid and phosphoric acid is used (the details will be described later). . By etching with the etching liquid MS, the first surface 100a of the glass substrate 100 can obtain a shape having a desired surface roughness, for example, a desired arithmetic average roughness Ra. The arithmetic average roughness Ra is preferably 0.3 nm or more, and more preferably, the arithmetic average roughness Ra is 0.45 nm or more. The upper limit value of the arithmetic average roughness Ra is preferably 0.6 nm or less, and more preferably 0.5 nm or less, from the viewpoint of roughness that prevents the glass substrate from being charged.

  The etching tank 11 is a substantially rectangular parallelepiped container having an open top. In the etching tank 11, an etching solution MS is stored so as to be almost full of the container. The etching tank 11 is arranged at a predetermined interval along the conveyance direction of the glass substrate 100. In the form of FIG. 2, three are arranged. In FIG. 2 of the present embodiment, three etching tanks 11 are arranged, but the number of arrangements may be one, two, or four or more. The number of arrangements is appropriately set based on the number of production, the etching solution and etching rate, the conveyance speed, and the like.

In each etching tank 11, one etching roller 12 is disposed so as to be immersed in the etching solution MS. In the etching solution tank 16, each etching tank 11 is communicated with the etching solution tank 16 by pipes 15a and 15b. The etchant in the etchant tank 16 supplies hydrofluoric acid (HF) and phosphoric acid (H ₃ PO ₄₎ , which are essential components of the etchant MS, and optional hydrochloric acid (HCl). The hydrofluoric acid tank 11 b and the phosphoric acid tank 11 c , And a hydrochloric acid tank 11d through flow rate adjusting valves 11e, 11f, and 11g.

  The roughening roller 12 absorbs (holds) the etching liquid MS and functions as a rotating body that is driven and rotated by a drive motor (not shown). When the roughening roller 12 is rotated by the drive motor, the glass substrate 100 in contact with the roughening roller 12 is transported in the direction in which the plurality of roughening rollers 12 are arranged (that is, the transport direction). . That is, the roughening roller 12 also has a function of conveying the glass substrate 100. A plurality of the roughening rollers 12 are arranged at a predetermined interval along the conveyance direction of the glass substrate 100. The plurality of roughening rollers 12 all rotate in the same direction.

  The roughening roller 12 is fixed in a state in which a part (specifically, the lower part) is immersed in the etching solution MS stored in one etching tank 11. The vertical length of the portion of the roughening roller 12 immersed in the etching solution MS is set as appropriate.

  The roughening roller 12 includes a core member 12a and a roller member 12b that covers the core member 12a. The core member 12a includes a shaft core made of SUS or the like and a columnar member made of a vinyl chloride material. The core member 12a may be a carbon shaft. The diameter of the core member 12a is appropriately set. The core member 12 a is a rotating shaft of the roughening roller 12.

  The roller member 12b is a cylindrical member having an outer diameter larger than that of the core member 12a and having an open center. The roller member 12b is made of a foamed resin that easily absorbs liquid, that is, a sponge. The sponge of the roller member 12b is made of PO, PVA, PU, or the like. The inner surface of the roller member 12b is in contact with the outer surface of the core member 12a.

  Here, the etching roller 12 (roller member 12b) absorbs the etching solution MS by being immersed in the etching solution MS. Then, a part of the etching solution MS absorbed by the roller member 12b is supplied and attached to the first surface 100a of the glass substrate 100 that contacts the etching roller 12 (roller member 12b) that absorbs and holds the etching solution MS. As a result, a wetted film layer of the etching liquid is formed between the glass substrate 100 and the roughening roller 12.

  The wetted film layer formed between the glass substrate 100 and the roughening roller 12 can be seen through from the surface direction of the glass substrate on the 110b side (the side to which no etching solution is attached), and the size of the wetted film layer. Can be observed. The contour of the wetted film layer SL of the etching solution adhering to the first surface 100a can be clearly specified through the glass substrate 100 on the second surface 100b side.

  The monitoring device 21 (see FIG. 5) is a device that observes the form of the wetted film layer SL of the etching solution. The form of the wetted film layer SL of the etchant is, for example, the wetted film layer of the etchant along the transport direction of the glass substrate 100 of the wetted film layer SL of the etchant adhered to the first surface 100a of the glass substrate 100. The length of the SL (liquid width in the transport direction, area, length in the direction perpendicular to the transport direction), etc., and the monitoring device 21 is a means for monitoring by displaying these forms, and further adding a measurement function It may be provided to measure while observing the form. The monitoring device 21 may include storage means for storing an image of the liquid contact film layer SL as necessary.

  The installation location of the monitoring device 21 is not particularly limited as long as it is installed so that a monitoring image can be output to the outside of the surface treatment device. It is installed at any appropriate place in the Pr1 process. The camera part of the monitoring device 21 is disposed above the roughening roller 12 located in the center of the conveying direction among the plurality of roughening rollers 12, and the form of the wetted film layer SL of the etching solution is An image is taken from the second surface 100b side of the glass substrate 100. When such a monitoring device 21 is not particularly provided, the form of the wetted film layer SL of the etching solution may be visually observed from the window frame provided in the housing 2 and monitored.

  Based on the observation of the form of the wetted film layer SL obtained by monitoring in this way, the etching liquid such as a squeeze roller is applied so that the size of the wetted film layer SL becomes constant during the continuous process. The amount of the etching solution applied to the glass substrate 100a can be adjusted using an adjusting means for controlling. Thereby, the application amount can be made constant.

For example, the size range of the liquid contact film layer SL serving as a reference that can achieve the target surface roughness Ra under conditions in which the amount of the etching solution retained by the porous material is appropriately adjusted in advance. Obtained (reference liquid contact film layer A: size, length, liquid width in the transport direction, etc.) and set so that the monitoring device 21 can compare with the form of the liquid contact film layer SL being processed. Can do.
Based on this comparison, the degree of adjustment of the coating amount of the etching solution can be determined. Compared with the reference wetted film layer A, the quality of the surface roughness can be maintained within a certain range by adjusting the coating amount of the etching solution more accurately.

  Further, for example, by setting the size of the reference wetted film layer A to a coating amount at which the etching liquid is unlikely to wrap around the glass substrate 110b, the wraparound management to the glass substrate 110b (to the etching liquid 110b) is set. Can be used to suppress sneaking around. In order to determine the amount of coating to prevent such wraparound, glass substrate (plate thickness, composition), sponge type (material, pore diameter, elasticity), transport speed, and etchant type (viscosity) The conditions can be set and the reference wetted film layer can be specified.

  The size of the wetted film layer SL of the etching solution is appropriately determined. For example, when the liquid width of the wetted film layer SL of the etching liquid varies over the longitudinal direction (axial direction) of the roughening roller 12, the roughened roller is used as the liquid width of the wetted film layer SL of the etching liquid. The average value of the liquid widths at a plurality of twelve longitudinal positions can be used. When measuring the area of the wetted film layer SL of the etchant, the area obtained by analyzing the image taken by the monitoring device 21 can be used.

  Furthermore, the etching apparatus can include a control device 23 (see FIG. 5) that controls the coating amount of the etching solution. The monitoring device 21 generates an output signal based on information (area, liquid width, etc.) on the form of the measured wet-contact film layer SL (see FIG. 5) of the etching solution, and outputs it to the control device 23. .

  The control device 23 receives the output signal from the monitoring device 21 and controls each part to adjust the coating amount of the etching solution MS on the glass substrate 100 based on the information on the form of the wetted film layer SL of the etching solution. Do. For example, the control device 23 may be connected to the squeeze roller 14 and the adjustment of the squeeze roller 14 may be synchronized based on information on the form of the wetted film layer SL of the etchant. Alternatively, the controller 23 is connected to a member that controls the supply and discharge of the etching liquid MS to the etching tank 11, and the liquid level height in the etching tank 11 is based on information on the form of the wetted film layer SL of the etching liquid. You may perform control, such as adjusting. Control of these units may be performed by means other than the control device 23.

  The squeezing roller 14 has a function of adjusting the amount of the etching liquid MS that is pressed against the roughening roller 12 and held by the etching roller 12. The squeeze roller 14 is made of a material having higher rigidity than the roller member 12b, for example, a material such as vinyl chloride or carbon. The squeezing roller 14 is a round bar having a cylindrical shape. The shape of the squeeze roller 14 is not limited to a round bar. As shown in FIG. 3, the squeezing roller 14 is disposed on the upstream side in the transport direction of the glass substrate 100 with respect to the core member 12 a that is the rotation shaft of the roughening roller 12.

  The squeezing roller 14 rotates following the rotation of the etching roller 12. Therefore, it rotates in the opposite direction to the roughening roller 12. Here, it is not necessary to separately use a motor or the like that rotates the squeezing roller 14, and thus the cost can be suppressed.

  As shown in FIG. 4, the squeezing roller 14 is supported by a support member 17 so that the vertical position and the horizontal position of the roughening roller 12 can be adjusted. That is, the squeezing roller 14 can adjust the contact position with the roughening roller 12. Thereby, the contact pressure of the squeeze roller 14 to the roughening roller 12 can be adjusted.

  The roughening roller 12 includes a mechanism that can adjust the relative position with respect to the glass substrate 100. That is, the rotating shaft of the roughening roller 12 can be moved closer to or away from the glass substrate 100 side. The etching tank 11 is provided with a mechanism that can adjust the liquid level of the etching liquid MS. Thereby, the quantity of the etching liquid MS which the roughening roller 12 adheres to the glass substrate 100 can be adjusted.

  Moreover, as above-mentioned, based on the form of the liquid-contacting film layer SL obtained with the monitoring apparatus 21, the quantity of etching liquid can be adjusted using a squeeze roller. The squeeze roller may be operated by being connected to the control device 23.

  The conveyance roller 18 includes a rotation shaft and a plurality of rollers. The roller is a cylindrical member fixed to the rotating shaft and to which an O-ring is attached. When the transport roller 18 is axially rotated by a drive motor (not shown), the glass substrate 100 supported in contact with the upper portion of the transport roller 18 is transported into the housing 2 that performs the roughening process Pr1. A plurality of transport rollers 18 are arranged at predetermined intervals along the transport direction of the glass substrate 100. All the transport rollers 18 rotate in the same direction.

<Roughening process>
A method for producing a glass substrate for a display, comprising a surface treatment step of continuously roughening the first surface of the main surface of the glass substrate,
In the surface treatment step, the glass substrate is transported on the roughening roller having the porous material holding the etching solution in the outer peripheral portion (including the peripheral surface portion), and the surface roughening roller and the glass plate Apply the etchant to the glass substrate to form a wetted film layer of the etchant between,
Etching solution is applied so that the size of the wetted film layer of the etching solution is almost constant while monitoring the size of the wetted film layer seen through from the surface direction of the glass substrate where the etching solution is not applied. The amount is adjusted to roughen the first surface of the main surface of the glass substrate.

  In the plurality of roughening rollers, it is preferable that each coating amount is adjusted to be substantially the same amount.

  It is preferable that adjustment of the coating amount is performed by a squeeze roller.

  It is preferable that the roughening roller has a continuous pore structure having a pore diameter of 10 μm to 100 μm and a porosity of 80% or more.

  The arithmetic average roughness Ra of the first surface after the surface treatment step is preferably 0.40 nm or more.

B. Embodiment 2. FIG. Surface treatment method including a mechanism for making the coating amount of the etching solution constant

  A glass substrate surface treatment apparatus is being transported by the transport roller 18 while the glass substrate 100 that has been subjected to the cleaning step S6 after the end face processing while being transported in a predetermined direction (transport direction) in a horizontal state is maintained in that state. 1 into the housing 2.

  The lower surface of the front end portion of the glass substrate 100 that enters the housing 2 contacts the roughening roller 12 and is supported by the roughening roller 12. The roughening roller 12 (roller member 12b) is immersed in the etching solution MS, thereby absorbing the etching solution MS and the upper portion of the roughening roller 12 (roller member 12b) absorbing the etching solution MS. The first surface 100 a whose surface is roughened comes into contact with the glass substrate 100, and the glass substrate 100 is transported along the transport direction by the rotational driving of the roughening roller 12. At this time, since the roughening roller 12 (roller member 12b) absorbs the etching liquid MS, the first surface 100a of the glass substrate 100 in contact with the roughening roller 12 (roller member 12b) has a rough surface. Etching liquid MS adheres via the activating roller 12 (roller member 12b). Thus, the etching liquid MS adheres to the first surface 100a while the glass substrate 100 is conveyed by the roughening roller 12, whereby the first surface 100a of the glass substrate is roughened. Thus, the etching liquid MS adheres to the first surface 100 a while the glass substrate 100 is conveyed by the roughening roller 12, and a wetted film layer of the etching liquid is formed between the glass substrate 100 and the roughening roller 12. During this time, the first surface 100a is roughened.

  When the glass substrate 100 is transported, the etching liquid is applied to the first surface 100a of the glass substrate by the roughening roller 12 having a porous material that has absorbed the etching liquid MS in the outer peripheral portion including the peripheral surface. While the glass substrate 100 is transported and applied, the size of the wetted film layer is made substantially constant while monitoring the size of the wetted film layer of the etching solution seen from the surface direction of the glass substrate 110b. The coating amount of the etching solution is adjusted, and the first surface of the main surface of the glass substrate is roughened.

  During the continuous treatment, the amount of the etchant in the continuous surface roughening treatment of the glass substrate 110a is adjusted by adjusting the coating amount of the etchant so that the size of the wetted film layer of the etchant is substantially constant. It becomes possible to maintain the coating amount within a certain range.

  The coating amount of the etching liquid MS can be adjusted so that the coating amount of the etching liquid MS is applied by the plurality of roughening rollers 12 and the coating amount of each of the roughening rollers 12 is substantially the same.

  The squeeze roller 14 may be used to adjust the coating amount.

  Since the contact time between the roughening roller 12 and the glass substrate 100 in the period from the time when the etching liquid MS adheres to the first surface 100a to the rinsing step Pr2 is the etching period, a desired period is obtained during this etching period. The rotational speed (conveying speed) of the roughening roller 12 that roughens the surface while conveying the glass substrate 100 can be adjusted so that the etching amount of 1 mm is achieved. For example, the contact time between the roughening roller 12 and the glass substrate 100 is increased by slowing the rotation speed of the roughening roller and increasing the transport time of the glass substrate 100 that transports the surface of the roughening roller 12. Thus, the degree and shape of etching of the glass substrate 100a can be adjusted.

<Apparatus configuration of rinse process Pr2>
In the rinsing step (Pr2), a plurality of transport rollers 18, a distilled water nozzle 25 that applies distilled water to the surface of the glass substrate that is not roughened, a cleaning nozzle 24 that cleans the roughened glass substrate surface, A nozzle 26 that sufficiently rinses the etching solution to be removed, and an ar knife that removes the liquid adhering to both surfaces of the glass substrate from the surface of the glass substrate so as to remain in the housing.

  The rinsing step (Pr2) is a space surrounded by the housing 4, and the temperature management of the space in the housing may or may not be performed. A slit through which the glass substrate 100 can pass is provided in a portion of the housing wall where the roughening step (Pr1) and the rinsing step (Pr2) are in contact.

  The cleaning nozzle 24 is provided along the transport path of the glass substrate 100 so as to wash away the etching solution MS attached to the first surface 100a of the glass substrate 100, and jets cleaning water toward the first surface 100a. The washing water used for the washing nozzle 24 is not necessarily pure water (distilled water). In the washing water tank 24a, the washed water once used for washing can be stored and circulated and reused for washing the first surface 100a of the glass substrate 100.

  The distilled water nozzle 25 is provided along the transport path of the glass substrate 100 from the main surface opposite to the first surface 100a in order to clean the main surface opposite to the first surface 100a of the glass substrate 100. Water is ejected toward the main surface opposite to the first surface 100a.

  The nozzle 26 ejects cleaning water toward the first surface 100 a in order to sufficiently wash away the etching solution remaining on the first surface 100 a of the glass substrate 100. The nozzle 26 is provided on the first surface 100 a side of the glass substrate 100 along the conveyance path of the glass substrate 100. The cleaning water ejected from the nozzle 26 may be the same pure water ejected from the distilled water nozzle 25, or the same washing water ejected from the cleaning nozzle 24.

  After cleaning the first surface a of the glass substrate 100 and the opposite surface, the liquid is blown off from the surface of the glass substrate with an air knife, and the housing 4 is moved by the transport roller 18 to perform the second cleaning step of the next step. It is carried out outside.

<Rinsing process>
After the roughening treatment step (Pr1), the glass substrate 100 moves in the conveying direction during the roughening treatment, so that when the etching liquid MS is attached to a part of the first surface 100a, the tip of the glass substrate 100 is moved. The portion contacts the conveying roller 18 in the housing 4. The glass substrate 100 proceeds to the rinsing process Pr2 by the transport roller 18.

  In the rinsing process Pr2, the first surface 100a is first cleaned with the cleaning water ejected from the cleaning nozzle 24, and the etching liquid MS is almost washed away, and then the first surface 100a is further ejected from the nozzle 26 (reused water). Etc.) At this time, the main surface opposite to the first surface 100 a of the glass substrate 100 is washed with pure water ejected from the distilled water nozzle 25. Thereafter, air is blown with an air knife toward the first surface 100a and the main surface opposite to the first surface 100a to blow the liquid. In this way, the rinsing process Pr2 is completed, and is carried out by the transport roller 18 in order to perform the second cleaning process S8.

(2-2) Etching Solution The etching solution MS in the present invention is an aqueous solution containing at least hydrofluoric acid HF and phosphoric acid H ₃ PO ₄ in pure water (the concentration described below also represents mass%). .
The concentration of phosphoric acid H ₃ PO ₄ in the etching solution MS is 0.3% (mass%) to 10%. If the concentration of phosphoric acid H ₃ PO ₄ exceeds 10%, it is not preferable from the viewpoint of drainage recovery. The concentration of phosphoric acid H ₃ PO ₄ in the etching solution MS is preferably 0.3% to 8%, more preferably 0.5% to 8%, and even more preferably 1%, from the viewpoint of the effect of suppressing the etching rate reduction. ~ 6%. When the etchant MS contains 1% or more of hydrofluoric acid and phosphoric acid H ₃ PO ₄ , hydrofluoric acid, a mixed acid of hydrofluoric acid and hydrochloric acid (same concentration as phosphoric acid), hydrofluoric acid, Compared with sulfuric acid (same concentration as phosphoric acid), the decrease in etching rate can be greatly suppressed under the same temperature condition. That is, the mixed acid of hydrofluoric acid HF and phosphoric acid H ₃ PO ₄ reduces the etching rate. High suppression effect. In the etching solution MS, the concentration of hydrofluoric acid in the mixed acid containing hydrofluoric acid HF and phosphoric acid H ₃ PO ₄ is preferably 0.3% to 10%, preferably 0.3% to 8%, 0 .3% to 6% is more preferable, and 0.3% to 5% is even more preferable. If the concentration of hydrofluoric acid exceeds 5%, the environmental load increases due to the problem of drainage recovery and the like. In the present embodiment, since the hydrofluoric acid concentration of the etching liquid MS can be kept low, the environmental load is small, and the waste liquid treatment cost of hydrofluoric acid can be suppressed.

As the etching solution MS containing hydrofluoric acid HF and phosphoric acid H ₃ PO ₄ is excellent in the etching rate lowering suppression effect, for example, the etching solution MS composed of 5% hydrofluoric acid HF is repeatedly used for 14 hours. The decrease in the etching rate is 45%, and the decrease in the etching rate after 44 hours of repeatedly using the mixed acid etching solution MS of 5% hydrofluoric acid HF and 5% hydrochloric acid HCl is 44%. The decrease in the etching rate after 15 hours of repeated use of the mixed acid etching solution MS of 5% hydrofluoric acid HF and 5% phosphoric acid H ₃ PO ₄ is 15%. Thus, the decrease in the etching rate of the glass substrate 100 in the etching solution MS containing hydrofluoric acid HF and phosphoric acid H ₃ PO ₄ is extremely small. These etching rates are all measured under the same temperature conditions.

Further, when the etching solution MS contains 1% or more of hydrofluoric acid and phosphoric acid H ₃ PO ₄ , compared with hydrofluoric acid, hydrofluoric acid and sulfuric acid (same concentration as phosphoric acid) under the same concentration of hydrofluoric acid. The amount of sludge generated can be kept low, and the mixed acid of hydrofluoric acid HF and phosphoric acid H ₃ PO ₄ also has an effect of suppressing the amount of sludge generated.
The etching liquid MS containing hydrofluoric acid HF and phosphoric acid H ₃ PO ₄ is excellent in the effect of suppressing the amount of sludge generation. For example, in the case of an etching liquid MS made of hydrofluoric acid HF with a sludge generation amount of 5% In contrast, the etching solution MS of a mixed acid of 5% hydrofluoric acid HF and 5% phosphoric acid H ₃ PO ₄ is 20 to 30% less. Thus, the mixed acid of hydrofluoric acid HF and phosphoric acid H ₃ PO ₄ is excellent in the effect of suppressing the amount of sludge.

For etchant MS containing hydrofluoric acid HF and phosphoric acid _H 3 PO _4, hydrofluoric acid HF and the concentration ratio of the phosphoric acid _H 3 PO _4: The (hydrofluoric acid), about 1: 1 to 30: is 1 , Preferably 1: 1 to 10: 1. The etching liquid MS of the present embodiment is a mixed acid containing hydrofluoric acid HF and phosphoric acid H ₃ PO ₄ as essential components. By using hydrofluoric acid and phosphoric acid as essential components, the etching rate is reduced and the effect is reduced. It has two simultaneous effects of suppressing the amount of sludge generated in the surface etching process.

  Conventionally known solutions containing sodium fluoride and phosphoric acid are not suitable as etching solutions for continuous roughening treatment because the etching rate itself is low.

The etching solution MS is mixed with the above combination (two kinds of mixed acids with hydrofluoric acid and phosphoric acid, or three kinds of mixed acids with hydrofluoric acid and phosphoric acid and hydrochloric acid), if necessary, sulfuric acid H ₂ SO ₄ , nitric acid HNO _3, etc. May be combined.

In the present embodiment, the etching solution MS may further contain hydrochloric acid HCl in addition to hydrofluoric acid HF and phosphoric acid H ₃ PO ₄ . In the case of three types of mixed acid in which hydrochloric acid HCl is combined with hydrofluoric acid HF and phosphoric acid H ₃ PO ₄ , generation of sludge can be further suppressed. Therefore, it is preferable that the etching liquid MS of this embodiment further includes hydrochloric acid HCl together with hydrofluoric acid HF and phosphoric acid H ₃ PO _{4. In} this case, the effect of suppressing the amount of sludge can be further enhanced.
In the etching solution MS, when hydrochloric acid HCl is combined with hydrofluoric acid HF and phosphoric acid H ₃ PO ₄ , the concentration of hydrochloric acid HCl is 0.3 mass% to 15 mass%, preferably hydrochloric acid HCl 0.3 mass% to 10 mass%. is there. In this case, the etchant MS, hydrofluoric acid HF is 0.3 wt% to 10 wt%, 0.3% to 10 wt% phosphoric acid _H 3 PO _4, the hydrochloride HCl 0.3% to 15% by weight It is. The concentration ratio of hydrofluoric acid HF and hydrochloric acid HCl (hydrofluoric acid: hydrochloric acid) when hydrochloric acid is used as the etching solution MS is approximately 1:10 to 5: 1.

(Roughening temperature)
The etching rate varies depending on the temperature of the etching solution MS. The temperature of the etching liquid MS is appropriately determined so as to obtain a predetermined etching rate. During the roughening treatment, it is preferable to keep the temperature of the etching solution MS constant so that the etching rate becomes constant. In this embodiment, the temperature of the etching MS is controlled between 20 ° C. and 30 ° C. Since the processing environment is deteriorated when the etching solution is vaporized, the temperature of the etching solution MS preferably does not exceed 40 ° C. Further, when the temperature of the etching MS is lower than 20 ° C., it becomes difficult to obtain a predetermined etching rate.

(Roughening time)
Roughening treatment time determines the surface roughness (arithmetic mean roughness Ra) obtained by roughening, and is used for the roughing treatment speed and roughening treatment based on the tact time of the previous process. It is set together with the number of etching rollers to be performed, the composition of the etching liquid MS used for the roughening treatment, and the etching rate.
The surface roughness obtained by roughening is preferably 0.3 nm or more, and more preferably, the arithmetic average roughness Ra is 0.40 nm or more. The upper limit value of the arithmetic average roughness Ra is preferably 0.60 nm or less, and more preferably 0.50 nm or less.

(2-3) Characteristics of glass substrate <Glass composition>
Examples of the glass composition to which the present embodiment is applied include the following (mass% display).
SiO _2: 50~70% _{(preferably, 57~64%), Al 2 O} 3: 5~25% ( _{preferably, 12~18%), B 2 O} 3: 0~15% ( preferably, 6 ~ 13%), and may optionally contain the following composition. As optional components, MgO: 0 to 10% (preferably 0.5 to 4%), CaO: 0 to 20% (preferably 3 to 7%), SrO: 0 to 20% (preferably, from 0.5 to 8%, more preferably 3~7%), BaO: 0~10% ( preferably 0-3%, more preferably _{0~1%), ZrO 2: 0~10} % ( preferably 0 to 4%, more preferably 0 to 1%). Furthermore, it is more preferable that R ′ ₂ O: more than 0.10% and 2.0% or less (provided that R ′ is at least one selected from Li, Na, and K).
_{Alternatively,} SiO 2: _{50~70% (preferably, 55~65%), B 2 O} 3: 0~10% ( _{preferably, 0~5%, 1.3~5%),} Al 2 O 3: 10-25% (preferably 16-22%), MgO: 0-10% (preferably 0.5-4%), CaO: 0-20% (preferably 2-10%, 2-6 %), SrO: 0 to 20% (preferably 0 to 4%, 0.4 to 3%), BaO: 0 to 15% (preferably 4 to 11%), RO: 5 to 20% (preferably Is preferably 8 to 20%, 14 to 19%) (wherein R is at least one selected from Mg, Ca, Sr and Ba). Furthermore, it is more preferable that R ′ ₂ O contains more than 0.10% and 2.0% or less (provided that R ′ is at least one selected from Li, Na and K).
<Young's modulus>
As a Young's modulus of the glass plate to which this embodiment is applied, for example, 72 (Gpa) or more is preferable, 75 (Gpa) or more is more preferable, and 77 (Gpa) or more is even more preferable.
<Strain point>
As a distortion rate of the glass substrate to which this embodiment is applied, 650 degreeC or more is preferable, for example, 680 degreeC or more is more preferable, 700 degreeC or more and 720 degreeC or more are still more preferable.

  As described above, according to the surface treatment method and the surface treatment apparatus of the present invention, even when the surface treatment is continuously performed on 1700 to 1900 (24 hours continuous treatment) level glass substrates, By controlling the coating amount of etching on one surface to be almost constant, and at the same time, controlling the coating amount to prevent the etching solution from flowing into the second surface of the glass substrate, a high-quality glass substrate can be obtained. Production at an efficiency level can be achieved. Thereby, a glass substrate useful for a high-definition display can be provided by an economically excellent method.

  As mentioned above, although the glass substrate manufacturing apparatus of this invention and the manufacturing method of the glass substrate were demonstrated in detail, this invention is not limited to the said embodiment, In the range which does not deviate from the main point of this invention, various improvement and a change are carried out. May be.

DESCRIPTION OF SYMBOLS 1 Glass substrate surface treatment apparatus 2, 4 Housing 11 Etching tank 16 Etching liquid tank 11b Hydrofluoric acid tank 11c Phosphoric acid tank 11d Hydrochloric acid tank 11e, 11f, 11g Flow rate adjustment valve 12a Core member 12b Roller member 14 Contact member 15 Piping 18 Conveying roller 33 Sensor 24 Washing water nozzle 24a Washing tank 1
25 Distilled water nozzle 25a Distilled water tank 26 Washing water nozzle 26a Washing tank 2
100 Glass substrate 100a First surface 100b Second surface

Claims (9)

A method for producing a glass substrate for a display, comprising a surface treatment step of continuously roughening the first surface of the main surface of the glass substrate,
In the surface treatment step, it is contacted with the glass substrate into a plurality of roughened roller having a porous material which holds the etchant to the outer peripheral portion, and conveyed while being supported, to contact the roughened roller to a glass substrate in the between the roughened roller and glass base plate, the first surface of the glass substrate such that the porous material is by supplying a part of the etchant to retain forming the wetted membrane layer etchant Apply the etchant to
The wetted film layer formed by applying the etchant is compared with a predetermined reference wetted film layer, and the wetted film layer of the wetted film formed by applying the etchant is in the direction of the rotation axis of the roughening roller. A display in which the coating surface of the glass substrate is roughened by adjusting the coating amount of the etching solution so that the average value of the liquid width at a plurality of locations along the reference liquid contact film layer is substantially equal to the liquid width of the reference wetted film layer Method for manufacturing glass substrate.   The manufacturing method of the glass substrate for a display of Claim 1 adjusted so that each coating amount may become substantially the same amount in these roughening rollers.   The manufacturing method of the glass substrate for a display of Claim 1 or 2 with which adjustment of the said coating amount is performed with a squeeze roller.   The method for producing a glass substrate for a display according to any one of claims 1 to 3, wherein the porous material has a continuous pore structure having a pore diameter of 10 µm to 100 µm and a porosity of 80% or more.   The manufacturing of the glass substrate for a display as described in any one of Claims 1-4 whose surface roughness Ra (arithmetic mean roughness) of the 1st surface of the glass substrate after the said surface treatment process is 0.40 nm or more. Method. An apparatus for manufacturing a glass substrate for display, including a surface treatment device for continuously roughening the first surface of the main surface of the glass substrate,
The surface treatment apparatus is such that a glass substrate is brought into contact with and supported by a plurality of roughening rollers having a porous material holding an etching solution at an outer peripheral portion, and the roughening roller is in contact with the glass substrate. Etching the first surface of the glass substrate so as to form a wetted film layer of the etching solution by supplying a part of the etching solution held by the porous material between the roughening roller and the glass substrate. An etching apparatus for applying a liquid;
Monitoring means for reflecting the form of the wetted film layer formed by application of an etching solution so that it can be compared with a predetermined reference wetted film layer;
The liquid width of the reference wetted film layer is approximately equal to the average value of the liquid widths at a plurality of locations along the rotation axis direction of the roughening roller of the wetted film layer formed by applying the etching liquid. An adjusting means for adjusting the coating amount of the etching solution as described above.   The glass substrate manufacturing apparatus for a display according to claim 6, wherein each of the plurality of roughening rollers is adjusted so that each coating amount is substantially the same.   The glass substrate manufacturing apparatus for a display according to claim 6 or 7, wherein the adjusting means is a squeezing roller.   The glass substrate manufacturing apparatus for a display according to any one of claims 6 to 8, wherein the porous material has a continuous pore structure having a pore diameter of 10 µm to 100 µm and a porosity of 80% or more.

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