KR20190073284A - Glass substrate for displays - Google Patents

Abstract

The present invention relates to a glass substrate for display in which peeling electrification hardly occurs when peeling off from an adsorption stage. In one glass surface of main surfaces of the glass substrate, the surface properties thereof has a deformation rate, Rsk, of greater than zero, wherein the Rsk represents symmetrical properties between a peak part and a valley part.

Description

[0001] GLASS SUBSTRATE FOR DISPLAYS [0002]

The present invention relates to a glass substrate for a display.

In a flat panel display (FPD), a substrate in which a transparent electrode, a semiconductor element, or the like is formed on a glass substrate is used as a substrate. For example, in a liquid crystal display (LCD), a transparent electrode, a TFT (Thin Film Transistor) or the like is formed on a glass substrate is used as a substrate.

The formation of the transparent electrode, the semiconductor element, and the like on the glass substrate is carried out while the glass surface of the glass substrate opposite to the semiconductor element formation surface is fixed on the absorption stage by vacuum adsorption. However, when the glass substrate on which the transparent electrode, the semiconductor element, or the like is formed is peeled off from the adsorption stage, the glass substrate is charged and electrostatic destruction of semiconductor elements such as TFTs occurs.

Patent Document 1 discloses a glass substrate in which the RSm value defined by the average interval of the irregularities is 0.05 μm or more and the deformation degree Rsk indicating the symmetry of the mountain portion and the valley portion is By the structure smaller than 0, the charge is reduced.

Japanese Patent Application Laid-Open No. 2014-201445

However, as in Patent Document 1, if the deformation degree Rsk is less than 0, there is a possibility that the area of the glass substrate in contact with the metal or the insulator plate is increased, and the static electricity of the glass substrate may become a problem.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and provides a glass substrate for a display in which peeling electrification hardly occurs when peeling off from an adsorption stage.

The present invention provides a glass substrate for a display characterized in that the glass surface of one of the main surfaces of the glass substrate has a degree of deformation Rsk showing a symmetry of a peak and a valley with a surface property thereof being larger than zero.

In the glass substrate for a display of the present invention, peeling electrification hardly occurs when peeling off from the adsorption stage.

Fig. 1 is an explanatory diagram of a manufacturing method of a glass substrate for a display according to an embodiment of the present invention, and is a schematic diagram showing an example of the construction of a heat treatment apparatus. Fig.
Fig. 2 is an explanatory diagram of a manufacturing method of a glass substrate for a display according to an embodiment of the present invention, and is a schematic diagram showing another structural example of the heat treatment apparatus. Fig.
3 is an explanatory diagram of a manufacturing method of a glass substrate for a display according to an embodiment of the present invention, and is a cross-sectional view schematically showing a float glass production apparatus.
Fig. 4 is a diagram showing the relationship between the slit width a, the processing length b, and the processing width c of the injector in the embodiment.
FIG. 5A is a conceptual diagram showing the concept of the root-mean-square roughness Rq, and FIG. 5B is a conceptual diagram showing the concept of the deformation Rsk showing the symmetry of the peak and valley.

[Glass substrate for display]

Hereinafter, a display glass substrate according to an embodiment of the present invention will be described.

The glass substrate for display of the present embodiment is not particularly limited and may be a broad glass composition such as soda lime silicate glass, aluminosilicate glass, borosilicate glass, and alkali-free glass.

The present inventors have focused on the surface properties of the main surface of the glass substrate in order to reduce the charge amount of the glass substrate. The inventors of the present invention have studied extensively and found that a glass substrate having a deformation degree Rsk of greater than 0 showing symmetry of a mountain part and a valley part has excellent properties.

In the glass substrate for a display according to the present embodiment, the glass surface of one of the main surfaces of the glass substrate has a degree of deformation Rsk showing a symmetry of the peak and valleys,

Rsk represents the rank-averaged height of the height Z (x) of the peak and valley on the main surface of the glass substrate at a reference length dimensioned by the square of the root mean square roughness Rq. In other words, Rsk means a degree of distortion (asymmetry) and is an index showing the symmetry of the peak and valley with respect to the average line (see the broken line in FIG. 5 (b)), It is called. 5 (a) is a conceptual diagram showing the concept of a root-mean-square roughness Rq. Rq is obtained by the following equation (1), and the root mean square value Z (x) It is an index indicating the square root. As shown in Fig. 5 (a), 1 represents the reference length of repetition of the crests and valleys along the main surface. 5 (b) is a conceptual diagram showing the concept of Rsk, and Rsk is obtained by the following equation (2).

As shown in Fig. 5 (b), Rsk has the following properties with respect to the average line indicated by the broken line by its value.

Rsk = 0: Symmetric with respect to the average line (normal distribution)

Rsk> 0: offset to the lower side of the average line

Rsk <0: offset toward the average line

As Rsk takes a value larger than 0, the area of contact between the glass substrate and the plate with the metal or the insulator is reduced, as shown in Fig. 5 (b), and the electrostatic charge of the glass substrate can be reduced .

In the glass substrate for a display of the present embodiment, Rsk is preferably larger than 0 and smaller than 1.5.

If Rsk is larger than 0, the contact area is reduced and electrostatic charge can be reduced. If Rsk is less than 1.5, chipping can be prevented from occurring on the surface of the glass substrate.

The arithmetic average roughness Ra of the surface property of the glass substrate for display of the present embodiment is preferably larger than 1 nm and not larger than 3.0 nm. Ra is an index indicating the average of the absolute values of Z (x) at the reference length l.

When Ra is larger than 1 nm, static charge can be reduced.

When Ra is 3.0 nm or less, scattering of light is small, reflected light is reduced, and glass transparency can be maintained.

In the glass substrate for a display of the present embodiment, the square-root-mean-square roughness Rq of the surface property is preferably larger than 1 nm and not larger than 5.0 nm. As described above, Rq is an index representing the root mean square of Z (x) in the reference length l.

If Rq is larger than 1 nm, static charge can be reduced. When Rq is 5.0 nm or less, scattering of light is small, reflected light is reduced, and glass transparency can be maintained.

It is preferable that the maximum height height Rz of the surface property of the glass substrate for display of the present embodiment is 8 to 35 nm. Rz is an index indicating the sum of the maximum value of the peak height Zp of the contour curve and the maximum value of the valley depth Zv at the reference length l. (The X-axis) of the outline curve, and the &quot; bone &quot; is the portion of the outline curve lower than the average line (X-axis) The direction toward the substrate side).

When Rz is 8 nm or more, the transmittance starts to increase. Further, when Rz is 35 nm or less, the scattering of light is small, the reflected light is reduced, and the transparency of the glass can be maintained since it is smaller than? / 4 (75 nm) of visible light.

In the glass substrate for a display of the present embodiment, the maximum peak height Rp of the surface property is preferably 3 to 20 nm. Rp is an index indicating the maximum value of the mountain height Zp of the contour curve at the reference length l.

When Rp is 3 nm or more, the charging of static electricity can be reduced. If Rp is 20 nm or less, chipping can be made less likely to occur on the surface of the glass substrate.

In the glass substrate for a display of the present embodiment, it is preferable that the maximum valley depth Rv of the surface property is 5 to 15 nm. Rv is an index indicating the maximum value of the valley depth Zv of the contour curve at the reference length l.

When Rv is 5 nm or more, the charging of static electricity can be reduced. When the Rv is 15 nm or less, chipping is less likely to occur on the surface of the glass substrate, and contaminants are less likely to adhere.

In the glass substrate for a display of the present embodiment, one glass surface is formed by dispersing a first convex portion having a height of 1.0 nm or more from the center of the surface roughness of the surface concave and convex, and the ratio of the area occupied by the area of the glass surface of the first convex portion Is preferably 15 to 40%.

If the area ratio of the first convex portion is 15% or more, the glass can be easily cut. If the area ratio of the first convex portion is 40% or less, transparency of the glass can be maintained.

In the glass substrate for a display of the present embodiment, one glass surface is formed by dispersing a second convex portion having a height of 1.5 nm or more on the center of the surface roughness of the surface convexo-concave, and the ratio of the area occupied by the area of the glass surface of the second convex portion Is preferably 5 to 30%.

If the area ratio of the second convex portion is 5% or more, the glass can be easily cut. If the area ratio of the second convex portion is 30% or less, transparency of the glass can be maintained.

In the glass substrate for a display of the present embodiment, a semiconductor element is preferably formed on the other glass surface of the main surface of the glass substrate.

The dimensions of the glass substrate for display of the present embodiment are not particularly limited, but they are suitable for a large glass substrate in order to suppress peeling electrification of the glass substrate. Specifically, it is preferable that the substrate size is longer than 2500 mm, shorter side is 2200 mm or longer, more preferably longer side is 3130 mm or longer, and shorter side is 2880 mm or longer.

The thickness of the plate is not particularly limited, but it is suitable for a thin glass substrate because it suppresses peeling electrification of the glass substrate. Specifically, it is preferably 1.0 mm or less, more preferably 0.75 mm or less, and further preferably 0.45 mm or less.

The display glass substrate of the present embodiment is preferably an alkali-free glass.

The alkali-free glass, to a weight percentage display of the oxide basis, 50 to 73%, Al ₂ O ₃ of 10.5 to 24%, B ₂ O ₃ from 0.1 to 12%, the MgO 0 to 8% of SiO _2, CaO (MgO + CaO + SrO + BaO) of 0 to 14.5%, 0 to 24% of SrO, 0 to 13.5% of BaO and 0 to 5% of ZrO ₂ , Is preferably 8 to 29.5%.

Further, the alkali-free glass, in weight percentages shown below oxide basis, 58 to 66% of SiO _2, Al ₂ O ₃ of 15 to 22%, B ₂ O ₃ 5 to 12%, the MgO 0 to 8% , MgO, CaO, SrO and BaO in an amount of 9 to 18% (MgO + CaO + SrO + BaO), CaO in an amount of 0 to 9%, SrO in an amount of 3 to 12.5% and BaO in an amount of 0 to 2% .

The alkali-free glass preferably contains 54 to 73% of SiO ₂ , 10.5 to 22.5% of Al ₂ O ₃ , 0.1 to 5.5% of B ₂ O ₃ , 0 to 8% of MgO, (MgO + CaO + SrO + BaO) of from 0 to 9%, CaO to 0 to 9%, SrO to 0 to 16% and BaO to 0 to 2.5% .

[Manufacturing method of glass substrate for display]

Next, a constitutional example of the manufacturing method of a glass substrate for a display of the present invention will be described.

Fig. 1 is an explanatory diagram of a manufacturing method of a glass substrate for a display according to an embodiment of the present invention, and is a schematic diagram showing an example of the construction of a heat treatment apparatus. Fig.

In the heat treatment apparatus 60 shown in Fig. 1, the plate glass 20 is conveyed in the direction of the arrow. The conveying means is not particularly limited, but is, for example, a conveying roll not shown. The heat treatment apparatus 60 and a heat treatment apparatus 62 described later are provided with a heater (not shown).

Here, the lower surface 22 of the plate glass 20 is the semiconductor element formation surface in the glass substrate for display, the upper surface 24 of the plate glass 20 is the glass surface opposite to the semiconductor element formation surface, , And when the semiconductor element is formed, it is fixed on the adsorption stage by vacuum adsorption.

The heat treatment apparatus 60 shown in FIG. 1 has an injector 70. The gas injected from the supply port 71 of the injector 70 onto the upper surface 24 of the plate glass 20 moves the forward or reverse flow path 74 with respect to the moving direction of the plate glass 20, ).

The injector 70 shown in Fig. 1 is a large-sized injector in which the flow of gas from the supply port 71 to the exhaust port 75 is evenly divided in forward and reverse directions with respect to the moving direction of the plate glass 20.

2 is a schematic diagram showing another example of the structure of the heat treatment apparatus. The heat treatment apparatus 62 shown in FIG. 2 has an injector 80. The injector 80 is an unidirectional-flow-type injector. An unidirectional-flow-type injector is an injector in which the flow of gas from the supply port 81 to the discharge port 85 is fixed to either the forward direction or the reverse direction with respect to the moving direction of the plate glass 20. The injector 80 shown in Fig. 2 has a forward flow path 84 from the supply port 81 to the discharge port 85 with respect to the moving direction of the plate glass 20. However, the present invention is not limited to this, and the flow path 84 from the supply port 81 to the exhaust port 85 may be reversed with respect to the moving direction of the plate glass 20.

In the method of manufacturing a glass substrate for a display of the present invention, a gas containing hydrogen fluoride (HF) is supplied to the upper surface 24 of the plate glass 20 from the supply ports 71 and 81 of the injectors 70 and 80 .

As a result, the fluorine concentration in the vicinity of the glass surface on the opposite side of the semiconductor element formation surface becomes higher than the fluorine concentration in the glass substrate, and the difference in work function between the glass substrate and the absorption stage becomes small, have.

In the method for producing a glass substrate for a display according to the present invention, the glass surface temperature at the time of supplying a gas containing HF, that is, the temperature of the upper surface 24 of the glass plate 20 is 500 to 900 캜. By setting the glass surface temperature at 500 占 폚 or higher, the following effects are exhibited.

Fluorine invades into the vicinity of the glass surface, and the fluorine concentration near the glass surface becomes higher than the fluorine concentration inside the glass substrate. The glass surface temperature is more preferably 550 DEG C or more, and more preferably 600 DEG C or more.

Further, by setting the glass surface temperature to 900 占 폚 or less, the following effects are exhibited.

The surface roughness Ra of the glass surface is prevented from becoming too large, and a uniform surface shape is formed. The glass surface temperature is more preferably 850 DEG C or less, and further preferably 800 DEG C or less.

In the method for producing a glass substrate for a display according to the present invention, the gas containing HF is preferably added with nitrogen (N ₂ ) or the like from the viewpoint of preventing corrosion of facilities such as the injectors 70 and 80 of the heat treatment apparatuses 60 and 62 An inert gas such as a rare gas is used as a carrier gas and supplied to the upper surface 24 of the plate glass 20 as a mixed gas with these carrier gases.

The HF concentration of the HF-containing gas supplied from the supply ports 71 and 81 of the injectors 70 and 80 is 0.5 to 30 vol%. By setting the HF concentration to 0.5 vol% or more, the following effects are exhibited.

Fluorine invades into the vicinity of the glass surface, and the fluorine concentration near the glass surface becomes higher than the fluorine concentration inside the glass substrate.

The HF concentration is more preferably 2 vol% or more, and still more preferably 4 vol% or more.

Further, by setting the HF concentration to 30 vol% or less, the following effects are exhibited.

It is possible to suppress the occurrence of defects on the glass surface formed by the reaction of HF with the glass surface and to suppress the decrease of the strength of the glass substrate. The HF concentration is more preferably 26 vol% or less, and still more preferably 22 vol% or less.

The distance D between the supply openings 71 and 81 of the injectors 70 and 80 and the upper surface 24 of the plate glass 20 is preferably 5 to 50 mm. The distance D is more preferably 8 mm or more. Further, the distance D is more preferably 30 mm or less, further preferably 20 mm or less. By making the distance D 5 mm or more, contact between the upper surface 24 of the plate glass 20 and the injectors 70 and 80 can be avoided even if the plate glass 20 vibrates due to an earthquake or the like. On the other hand, by setting the distance D to 50 mm or less, the gas can be prevented from diffusing into the device, and a sufficient amount of gas can reach the upper surface 24 of the plate glass 20 with respect to a desired amount of gas.

The distance L of the injectors 70 and 80 in the moving direction of the plate glass 20 is preferably 100 to 500 mm. The distance L is more preferably 150 mm or more, and still more preferably 200 mm or more. The distance L is more preferably 450 mm or less, and further preferably 400 mm or less. By setting the distance L to 100 mm or more, the supply ports 71 and 81 and the exhaust ports 75 and 85 can be provided. In particular, the distance L of the injector 70 is preferably 150 mm or more, and the distance L of the injector 80 is preferably 100 mm or more. On the other hand, by setting the distance L to 500 mm or less, it is possible to suppress the heat amount of the plate glass 20 by the injectors 70, 80, and thus the output of a plurality of heaters can be suppressed.

It is preferable that the distance in the width direction of the plate glass 20 of the injectors 70 and 80 is longer than the product area in the corresponding direction of the plate glass 20. [ When the method for producing a glass substrate for a display according to the present invention is carried out as online processing, it is preferably at least 3000 mm, more preferably at least 4000 mm.

The flow rate (linear velocity) of the gas containing HF is preferably 20 to 300 cm / s. By setting the flow velocity (linear velocity) to 20 cm / s or more, the air flow of the gas containing HF is stabilized, and the glass surface can be treated uniformly. The flow velocity (linear velocity) is more preferably 50 cm / s or more, and still more preferably 80 cm / s or more.

As described later, when the method for producing a glass substrate for a display according to the present invention is carried out as on-line treatment, the flow velocity (linear velocity) is set to 300 cm / s or less to suppress diffusion of gas into the inside of the gradual cooling apparatus A sufficient amount of gas can reach the top surface of the glass ribbon. The flow velocity (linear velocity) is more preferably 250 cm / s or less, and still more preferably 200 cm / s or less.

The manufacturing method of the glass substrate for a display of the present invention may be performed as online processing or as offline processing. The &quot; on-line processing &quot; in the present specification refers to a case where the method of the present invention is applied in the slow cooling process in which the glass ribbon formed by the float method or the down-draw method is slowly cooled. On the other hand, &quot; offline processing &quot; refers to a case where the method of the present invention is applied to a plate glass which is formed and cut to a desired size. Therefore, the plate glass in this specification includes a glass ribbon molded by a float method or a down-draw method in addition to a plate glass cut into a desired size.

The process for producing a glass substrate for a display of the present invention is preferably carried out as online processing for the following reasons.

If the process is offline, it is necessary to increase the process. On the other hand, if the process is on-line, there is no need to increase the process, and the process can be performed at low cost. Further, in the case of off-line processing, the gas containing HF is transferred between the glass substrates to the semiconductor element formation surface of the glass substrate. On the other hand, if the on-line treatment of the glass ribbon is carried out, have.

A manufacturing process for a plate glass such as a glass substrate for a display includes a melting process in which a glass raw material is dissolved and made into a molten glass, a molding process in which a molten glass obtained in the melting process is molded into a strip to form a glass ribbon, And a slow cooling step of slowly cooling the obtained glass ribbon. Examples of the forming step include a float forming step by the float method and a down-draw forming step by the down-draw method.

In the case where the process for producing a glass substrate for a display of the present invention is carried out as on-line treatment, a gas containing HF is supplied to the top surface of the glass ribbon in the slow cooling process.

3 is an explanatory diagram of a manufacturing method of a glass substrate for a display according to an embodiment of the present invention, and is a cross-sectional view schematically showing a float glass production apparatus.

A float glass manufacturing apparatus 100 shown in Fig. 3 comprises a dissolving apparatus 200 for dissolving a glass raw material 10 into a molten glass 12 and a molten glass 12 supplied from the dissolving apparatus 200 And a slow cooling device 400 for slowly cooling the glass ribbon 14 formed by the molding device 300. The cooling device 400 is a device for cooling the glass ribbon 14,

The melting apparatus 200 includes a melting vessel 210 for receiving the molten glass 12 and a burner 220 for forming a flame above the molten glass 12 accommodated in the melting vessel 210. The glass raw material 10 charged into the melting vessel 210 gradually fuses into the molten glass 12 by the radiant heat from the flame formed by the burner 220. The molten glass 12 is continuously supplied from the melting tank 210 to the molding apparatus 300.

The molding apparatus 300 has a bath 320 for receiving the molten tin 310. The molding apparatus 300 forms the glass ribbon 14 by forming a molten glass 12 continuously flowing on the molten tin 310 in a strip shape by flowing the molten glass 12 in a predetermined direction on the molten tin 310. The temperature of the atmosphere in the molding apparatus 300 is lowered from the inlet to the outlet of the molding apparatus 300. The atmospheric temperature in the molding apparatus 300 is adjusted by a heater (not shown) or the like installed in the molding apparatus 300. The glass ribbon 14 is cooled while flowing in a predetermined direction and is pulled up from the molten tin 310 in the region downstream of the bath 320. The glass ribbon 14 pulled up from the molten tin 310 is conveyed to the slow cooling device 400 by the lift-out roll 510.

The gradual cooling apparatus 400 slowly softens the glass ribbon 14 formed by the molding apparatus 300. The slow cooling apparatus 400 includes a slow cooling furnace 410 having a heat insulating structure and a plurality of transport rolls 420 disposed in the annealing furnace 410 and transporting the glass ribbon 14 in a predetermined direction . The ambient temperature in the annealing furnace 410 is lowered from the inlet to the outlet of the annealing furnace 410. The ambient temperature in the annealing furnace 410 is adjusted by the heater 440 or the like installed in the annealing furnace 410. The glass ribbon 14 taken out from the outlet of the gradual cooling path 410 is cut to a predetermined size by a cutter and shipped as a product.

At least one of both surfaces of the glass substrate may be polished and the glass substrate may be cleaned before shipment as a product, if necessary. The glass substrate for a display according to the present invention has a glass surface opposite to the semiconductor element formation surface of the glass substrate corresponding to the top surface of the glass ribbon 14, Corresponds to the bottom surface of the glass ribbon 14.

In the method of manufacturing a glass substrate for a display according to the present invention, the fluorine concentration near the glass surface on the opposite side of the semiconductor element formation surface is made higher than the fluorine concentration inside the glass substrate to reduce the difference in work function between the glass substrate and the absorption stage , It is preferable to polish only the bottom surface of the glass ribbon 14 when performing polishing in order to suppress peeling electrification of the glass substrate. The semiconductor element formation surface of the glass substrate is polished by a polishing tool while supplying a cerium oxide aqueous solution. During polishing, a part of the aqueous cerium oxide solution migrates to the glass surface on the side opposite to the semiconductor element formation surface of the glass substrate, and becomes a slurry residue.

The glass substrate is cleaned by, for example, shower cleaning, slurry cleaning using a disc brush, or shower rinsing. The slurry cleaning is carried out by polishing with a disc brush while supplying a slurry (for example, a cerium oxide aqueous solution or an aqueous solution of calcium carbonate) to the glass surface on the side opposite to the semiconductor element formation surface of the glass substrate, Remove the remaining slurry residue from the glass surface.

The float glass manufacturing apparatus 100 shown in Fig. 3 is provided with the injectors 70, 70 disposed above the glass ribbon 14 in the gradual cooling apparatus 400 in order to perform the on- And the gas containing hydrogen fluoride (HF) is supplied to the top surface of the glass ribbon 14 by using the injectors 70 and 80. [ The heat treatment apparatuses 60 and 62 shown in Figs. 1 and 2 correspond to the gradual cooling apparatus 400 shown in Fig. 3 when the method for producing a glass substrate for a display of the present invention is carried out as online processing.

3, the injectors 70 and 80 are provided in the gradual cooling apparatus 400. However, the float glass manufacturing apparatus according to another embodiment of the present invention is not limited to the glass surface temperature at the time of supplying the gas containing HF The injector may be provided in the molding apparatus 300. [

[Example]

Hereinafter, examples and comparative examples of the present invention will be described in detail. The present invention is not limited to these descriptions.

As the on-line treatment, the manufacturing method of the glass substrate for display of the present invention was carried out.

SiO ₂ : 59.5%, Al ₂ O ₃ : 17%, B ₂ O ₃ : 8%, MgO: 3.3%, and the like were measured using the float glass manufacturing apparatus 100 shown in FIG. , CaO: 4%, SrO: 7.6%, BaO: 0.1%, ZrO 2: containing 0.1%, MgO + CaO + SrO + BaO: is 15%, the balance being an inevitable impurities, the content of alkali metal oxide An alkali-free glass plate having a thickness of 0.5 mm and a total content of 0.1% or less was prepared.

The molten glass 12 is melted into the molten glass 12 in the dissolving apparatus 200 and then the molten glass 12 is supplied to the molding apparatus 300 to form the molten glass 12 into a belt shape, The ribbon 14 was obtained. After the glass ribbon 14 is drawn out from the outlet of the molding apparatus 300, the glass ribbon 14 is slowly cooled in the gradual cooling apparatus 400.

An injector 70 having a distance L of 300 mm in the moving direction of the glass ribbon 14 was provided at a position where the temperature of the glass ribbon 14 in the gradual cooling apparatus 400 was 500 ° C.

4 is a graph showing the relationship between the slit width (a), the processing length (b), and the processing width (c) of the injector in Experimental Example 2. The flow rate (L / min), the treatment time (sec), and the linear velocity (mm / sec) of the gas including a (mm), b (mm), c .

a: 5mm

b: 392 mm

c: 1200 mm

Flow rate of gas containing HF: 120 L / min

Processing time: 4 sec

Line speed: 500mm / sec

The distance D between the supply port 71 of the injector 70 and the upper surface of the glass plate 20 was set to 10 mm.

The glass surface temperature (described as temperature in Table 1) and the HF concentration (vol%) at the time of supplying the gas containing HF were set as shown in Table 1 below. In Table 1, Examples 1 to 4 are Examples, and Example 5 is Comparative Example.

The obtained glass plate was evaluated as follows.

[Surface property parameter of glass surface]

The glass substrate obtained by the above procedures was cut into a width of 5 mm and a length of 5 mm and the deformation Rsk, the arithmetic average roughness Ra, the square-average square roughness Rq, the maximum height Rz, the maximum mountain height Rp, Rv (Specification No. JIS B0601: 2013, name of the product Geometrical characteristic means (GPS) -Surface property: Contour curve method -Term, Definition and surface property parameter) were measured by the following methods. The glass surface of the glass substrate was observed using an atomic force microscope (product name: SPI-3800N, manufactured by Seiko Instruments Inc.). The cantilever used SI-DF40P2. Observation was performed at a scan rate of 1 Hz (number of data in the area: 256x256) using a dynamic force mode for a scan area of 5 占 퐉 占 5 占 퐉. Based on this observation, surface property parameters at each measurement point were calculated. The calculation software used software (software name: SPA-400) attached to the atomic force microscope.

[Peeling electrification amount of glass substrate]

The amount of peeling electrification of the glass substrate obtained in the above procedure was measured by the following method. A glass substrate having a width of 410 mm, a length of 520 mm and a thickness of 0.5 mm was brought into contact with a vacuum adsorption stage made of SUS304, and then the adsorption and release of the glass substrate were repeated for 110 cycles. Thereafter, the glass substrate was peeled off from the vacuum adsorption stage using a lift pin. The change in surface potential until the glass substrate rose 5 cm apart from the vacuum adsorption stage was measured with a surface electrometer (product name: MODEL 341B, manufactured by Trek Japan Co.). The peak value of the measurement result was taken as the peeling electrification amount.

With regard to the chargeability, the case where the absolute value of the charge amount was 12 kV or less was rated as &amp; cir &amp; Regarding transparency, those satisfying both of the following A and B were evaluated as &amp; cir &amp; A: 90% or more of spectroscopy at each wavelength of a haze meter of 0.8% or less (Sugashikuchi: touch type haze computer model: HZ-1), B: 420 nm, 440 nm, 500 nm, 630 nm, 700 nm (SHIMADZU: spectrophotometer UV2600) It represents transmittance.

Good results were obtained with respect to the chargeability and transparency of the glass substrates of the examples, but good results were not obtained with respect to the chargeability and transparency of the glass substrates of the comparative examples.

Although the present invention has been described in detail with reference to specific embodiments thereof, it is apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention. The present application is based on Japanese Patent Application 2017-242075 filed on December 18, 2017, the contents of which are incorporated herein by reference.

10: Glass raw material
12: molten glass
14: Glass ribbon
20: Plate glass
22: When you
24: upper surface
60, 62: Heat treatment apparatus
70, 80: injector
71, 81: supply port
74, 84: Euro
75, 85: Exhaust port
100: Float glass manufacturing apparatus
200: dissolution apparatus
210:
220: Burner
300: forming device
310: molten tin
320: Bathtub
400: slow cooling device
410: slow cooling
420: conveying roll
440: Heater
510: Lift-out roll

Claims (10)

Wherein a glass surface of one of the main surfaces of the glass substrate has a deformation Rsk showing a symmetry of a peak and a valley in the surface property thereof is larger than zero. The glass substrate for a display according to claim 1, wherein the deformation Rsk is larger than 0 and smaller than 1.5. The glass substrate for a display according to claim 1 or 2, wherein the arithmetic average roughness Ra of the surface property is larger than 1 nm and smaller than 3.0 nm. The glass substrate for a display according to any one of claims 1 to 3, wherein the square mean square roughness Rq of the surface property is larger than 1 nm and smaller than 5.0 nm. The glass substrate for a display according to any one of claims 1 to 4, wherein a maximum height Rz of the surface property is 8 to 35 nm. The glass substrate for a display according to any one of claims 1 to 5, wherein the maximum peak height Rp of the surface property is 3 to 20 nm. The glass substrate for a display according to any one of claims 1 to 6, wherein a maximum valley depth Rv of the surface property is 5 to 15 nm. The glass sheet according to any one of claims 1 to 7, wherein the one glass surface is provided with a first convex portion having a height of 1.0 nm or more on the surface of the convexo-concave surface, Wherein the ratio of the area occupied by the surface area is 15 to 40%. The glass sheet according to any one of claims 1 to 8, wherein the one glass surface is provided by dispersing a second convex portion having a height of 1.5 nm or more on a surface roughness center plane of the surface convexo-concaves, Wherein the ratio of the area occupied by the surface area is 5 to 30%. The glass substrate for a display according to any one of claims 1 to 9, wherein a semiconductor element is formed on the other glass surface of the main surface of the glass substrate.

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