KR20150054819A - Glass substrate for display and method for manufacturing glass substrate for display - Google Patents

Abstract

The present invention provides a glass substrate for a display in which the surface of the side in contact with the adsorption stage is sufficiently small in contact area with the adsorption stage and a method of manufacturing the same. A glass substrate for display 1 having a surface 21 on which fine particles 3 are adhered on a glass substrate 2 and an illuminance Ra of 0.5 to 10 nm on the surface 21 is provided. It is preferable that the average particle diameter of the fine particles 3 is 50 nm or less. It is preferable that the fine particles 3 contain a metal oxide.

Description

Technical Field [0001] The present invention relates to a glass substrate for a display,

The present invention relates to a glass substrate for a display and a manufacturing method thereof.

In a flat panel display such as a plasma display panel (PDP), a liquid crystal display (LCD), a light emitting device display (ELD), and a field emission display (FED), a substrate on which a transparent electrode, a semiconductor element, have. For example, in an LCD, a substrate on which a transparent electrode, a thin film transistor (TFT), or the like is formed on a glass substrate is used.

Formation of a transparent electrode, a semiconductor element, and the like on a glass substrate is carried out while the glass substrate is fixed on the adsorption stage by vacuum adsorption.

However, the glass substrate is an insulator, and is easily charged by adhesion or friction with the dissimilar material and strongly adhered to the adsorption stage. Therefore, when the glass substrate on which the semiconductor element or the like is formed is peeled from the adsorption stage, the glass substrate is difficult to peel off from the adsorption stage, and if it is forcibly peeled off, the glass substrate is broken.

In addition, when peeling electrification occurs when the glass substrate is peeled from the adsorption stage, electrostatic destruction of semiconductor elements such as TFTs formed on the glass substrate occurs.

Therefore, the glass substrate surface on the side in contact with the adsorption stage is roughened to reduce the contact area between the glass substrate and the adsorption stage. If the contact area between the glass substrate and the adsorption stage is made small, the amount of charge of the glass substrate is reduced, and it is easy to peel off the adsorption stage and the amount of peeling electrification is reduced.

As a method of roughening treatment, for example, a method of spraying a slurry containing liquid and abrasive grains on one surface of a glass substrate and polishing the surface of the glass substrate with a brush is known (Patent Document 1).

Japanese Patent Application Laid-Open No. 2001-343632

However, in the glass substrate subjected to the roughening treatment by the conventional method, the occurrence of peeling electrification at the time of peeling the glass substrate from the adsorption stage is not sufficiently suppressed, and electrostatic destruction of the semiconductor element occurs in some cases. Further, the conventional glass substrate subjected to the roughening treatment is required to be more easily peeled off from the adsorption stage.

The present invention provides a glass substrate for display having a surface capable of sufficiently reducing the contact area with the adsorption stage and a method of manufacturing the same.

[1] A glass substrate for display having a surface on which fine particles are adhered on a glass substrate, and a surface roughness Ra of 0.5 to 10 nm on the surface.

[2] The glass substrate for display according to [1], wherein the fine particles have an average particle size of 50 nm or less.

[3] The glass substrate for display according to [1] or [2], wherein the fine particles comprise a metal oxide.

[4] The glass substrate for display according to any one of [1] to [3], wherein the fine particles are one or more kinds selected from ceria fine particles, zirconia fine particles, silica fine particles and alumina fine particles.

[5] A production method of a glass substrate for display according to any one of [1] to [4], comprising a coating step of applying a coating liquid containing fine particles on one surface of a glass substrate, A rinsing step of rinsing a part of the glass substrate with pure water, and a drying step of drying the glass substrate.

Since the glass substrate for a display of the present invention has an illuminance Ra of 0.5 to 10 nm on one side, the contact area with the adsorption stage can be made sufficiently small by disposing one surface on the side in contact with the adsorption stage. Therefore, the glass substrate for display of the present invention can easily peel off from the adsorption stage while peeling off is difficult to occur.

According to the method for producing a glass substrate for a display of the present invention, a glass substrate for display can be manufactured which has a surface roughness that can sufficiently reduce the contact area with the adsorption stage.

1 is a cross-sectional view showing an example of a glass substrate for a display of the present invention.
Fig. 2 is a view for explaining a manufacturing method of the glass substrate for display shown in Fig. 1. Fig.
3 is a view for explaining the manufacturing method of the glass substrate for display shown in Fig.
4 is a cross-sectional view showing an example of a glass substrate used for a display glass substrate of the present invention.
5 (a) to 5 (c) are views for explaining another manufacturing method of the glass substrate for display shown in Fig.

≪ Glass substrate for display >

1 is a cross-sectional view showing an example of a glass substrate for a display of the present invention. The display glass substrate 1 shown in Fig. 1 has a back surface 21 (one surface (upper surface in Fig. 1)) on which the fine particles 3 are adhered on a glass substrate 2. Fig.

The back surface 21 of the glass substrate for display 1 is a surface disposed in contact with the adsorption stage when transparent electrodes, semiconductor elements and the like are formed on the glass substrate for display 1.

On the other hand, the surface 2b of the glass substrate 1 for display (the surface opposite to the one surface (lower surface in FIG. 1)) is a surface on which a transparent electrode, a semiconductor element or the like is formed. As shown in Fig. 1, the surface 2b of the glass substrate 1 for display includes the surface of the glass substrate 2. Fig. The surface 2b of the glass substrate for display 1 (the surface of the glass substrate 2) is a smooth surface having an illuminance Ra of about 0.2 to 0.4 nm.

The illuminance Ra of the back surface 21 of the glass substrate for a display 1 shown in Fig. 1 is preferably 0.5 to 10 nm, more preferably 0.7 to 5 nm, and more preferably 1 to 4 nm.

The roughness Ra in the present invention is calculated by measuring the measurement area of 5 占 퐉 占 5 占 퐉 by using an atomic force microscope and calculating the average value of the arithmetic mean height defined in JIS B0601 (2001). It is possible to measure the " roughness " of the glass substrate 2 purely without considering the "bending" of the glass substrate 2 when measuring a minute measurement area of 5 μm × 5 μm using an atomic force microscope have.

When the roughness Ra of the back surface 21 is 0.5 nm or more, when a transparent electrode, a semiconductor element or the like is formed on the front surface 2b of the glass substrate for display 1, the contact area between the back surface 21 and the absorption stage is sufficiently small . As a result, the glass substrate for display 1 can be easily peeled off from the adsorption stage and peeling electrification is less likely to occur. When the illuminance Ra of the back surface 21 is 10 nm or less, occurrence of scattering of visible light is suppressed, and high transmittance of visible light can be maintained.

The attached surface 2a to which the fine particles 3 on the glass substrate 2 are adhered may be a flame polished surface having a roughness Ra of about 0.2 nm, for example, in the glass substrate for a display 1 shown in Fig. 1 And may be a surface having a roughness Ra of about 0.4 nm, which is roughened as shown in Fig.

The contact area between the back surface 21 of the glass substrate 2 and the adsorption stage is further reduced in the glass substrate for display 1 on which the surface 2a to be adhered is roughened. Accordingly, the glass substrate for display 1 can be easily peeled off from the peeling off from the adsorption stage, and the occurrence of peeling electrification can be suppressed more effectively.

Examples of the glass substrate 2 include an alkali-containing glass substrate such as a soda-lime silicate glass substrate, a non-alkali glass substrate such as a borosilicate glass substrate, and the like.

Although the shape and the plane dimension of the glass substrate 2 are not particularly limited, it is preferable that the glass substrate 2 is a rectangular substrate having a length of 100 to 3000 mm both in the vertical and horizontal directions. The thickness of the glass substrate 2 is preferably 0.1 to 3 mm for use as a display substrate.

When the glass substrate 2, the alkali-free glass substrate, the composition of the glass substrate 2 is, for example, SiO ₂ in a molar percentages: 66 to _{70%, Al 2 O 3:} 9 to 14%, B ₂ O ₃ : 6 to 9.5%, MgO: 1 to 5%, CaO: 1 to 6%, SrO: 2 to 8% and MgO + CaO + SrO: 9 to 16% desirable. When the glass substrate 2 is a non-alkali glass substrate, it is particularly preferable that the thickness is 0.3 to 1.0 mm.

The fine particles 3 are preferably those containing a metal oxide. The fine particles 3 containing the metal oxide are preferably at least one selected from ceria (CeO ₂ ) fine particles, zirconia (ZrO ₂ ) fine particles, silica (SiO ₂ ) fine particles and alumina (Al ₂ O ₃ ) fine particles In particular, it is preferable to use ceria microparticles from the viewpoint of the adhesion force due to the difference in surface potential.

The average particle diameter of the fine particles 3 is not particularly limited, but is preferably 50 nm or less, more preferably 5 to 30 nm, and more preferably 5 to 30 nm, as long as the surface 21 having Ra of 0.5 to 10 nm can be formed. More preferably 10 to 20 nm.

In addition, the average particle size of the fine particles (3) is a conversion value from the specific surface area measurement value according to the BET adsorption method (according to JIS Z8830 Established in 1990 (latest revision year 2013)).

When the average particle size of the fine particles 3 is 50 nm or less, when the fine particles 3 are adhered to the glass substrate 2 using the coating liquid containing fine particles, the fine particles 3 in the coating liquid are hardly settled, The fine particles 3 can be favorably dispersed in the liquid, and the handling of the coating liquid is facilitated. If the average particle diameter of the fine particles 3 is 50 nm or less, the fine particles 3 may not be washed out in a rinsing step to be described later or fall off after adhering to the glass substrate 2, .

<Manufacturing Method>

Next, as an example of a manufacturing method of a glass substrate for a display of the present invention, a manufacturing method of a glass substrate for a display shown in Fig. 1 will be described with reference to Figs. 2 and 3. Fig.

In order to manufacture the glass substrate for display 1 shown in Fig. 1, first, a glass substrate 2 is prepared.

Next, as shown in Fig. 2, on the surface 2a of the glass substrate 2 (surface on the back surface 21 of the glass substrate 1 for display), fine particles 3 are contained (Coating step).

The fine particles 3 are supplied onto the adhered surface 2a of the glass substrate 2 and the adhesion force due to the difference in surface energy or surface potential between the glass substrate 2 and the fine particles 3 The fine particles 3 are adhered to the attached surface 2a of the glass substrate 2. [

Examples of the coating liquid 4 containing the fine particles 3 include those in which the fine particles 3 are dispersed in water. The content of the fine particles 3 in the coating liquid varies depending on the density of the fine particles 3 on the rear surface 21 of the glass substrate for display 1, the coating amount of the coating liquid 4, Viscosity, and the like, and is not particularly limited. The coating liquid 4 may contain an additive such as a pH adjuster such as nitric acid or a permittivity adjusting agent such as an alcohol if necessary.

As the coating liquid 4, the fine particles 3 may be dispersed in a mixed solution of water and ethanol or a mixed solution of water and glycerin.

The coating amount of the coating liquid 4 can be appropriately determined depending on the content of the fine particles 3 in the coating liquid and the like so that the Ra on the attached surface 2a of the glass substrate 2 is 0.5 to 10 nm desirable.

The application method of the application liquid 4 is not particularly limited, but it is preferable that the application liquid 4 can be applied only to the side of the glass substrate 2 to which the attachment surface 2a is attached. For example, A method of dropping the coating liquid 4 with the surface 2a of the substrate 2 facing upward and a method of coating the surface with the surface to be attached 2a facing downward using a coating roll or a spray .

Next, as shown in Fig. 3, a rinsing step is performed in which a part of the fine particles 3 on the attached surface 2a is washed with pure water 5. In the rinsing process, for example, a method of supplying pure water 5 using a spray nozzle on the adhered surface 2a of the glass substrate 2 to which the coating liquid 4 is applied can be used.

In this embodiment, even if the rinsing step is performed, fine particles (not shown) adhering to the surface 2a of the glass substrate 2 due to the adhesion force due to the difference in surface energy or surface potential 3 remain unremoved and only the excess fine particles 3 present on the attached surface 2a of the glass substrate 2 are selectively removed.

In the present embodiment, the extra fine particles 3 mean fine particles 3a and 3 which do not directly interact with the attached surface 2a of the glass substrate 2. [

Subsequently, the glass substrate 2 on which the rinsing process has been completed is dried, and the pure water 5 used in the rinsing process is removed (drying step). The drying method is not particularly limited, but an air blow drying method and the like can be used.

In this embodiment, the rinsing step is performed before the drying step to remove the excess fine particles 3a, 3 present on the surface 2a of the glass substrate 2 to be attached. This causes the excess fine particles 3a and 3 remaining not attached on the attached surface 2a to flow on the surface 2b of the glass substrate for display 1 in the drying step, To the surface 2b of the glass substrate 1 for the first time.

The fine particles 3 on the attached surface 2a of the glass substrate 2 are adhered to the adherend surface 2a by the adhering force caused by the difference in surface energy or surface potential, It is difficult to remove. Therefore, the fine particles 3 remain at a sufficient density on the adhered surface 2a after the drying step. Therefore, the illuminance Ra of the rear surface 21 of the glass substrate for display 1 after the drying process is in the range of 0.5 to 10 nm. Further, even if the drying step is carried out, the fine particles 3 on the attached surface 2a are hard to be removed, so that the drying step can be carried out by a method which can be easily and efficiently dried, such as the air blow drying method have.

By the above steps, the glass substrate for display 1 shown in Fig. 1 is obtained.

Thereafter, a transparent electrode, a semiconductor element, or the like is formed on the surface 2b (lower surface in Fig. 1) of the glass substrate for a display 1 shown in Fig. 1 thus obtained. Both surfaces of the glass substrate for display 1 may be scrubbed before forming transparent electrodes, semiconductor elements, and the like. In the display glass substrate 1 shown in Fig. 1, the fine particles 3 are adhered to the adhered surface 2a of the glass substrate 2 by an adhesive force due to difference in surface energy or surface potential Therefore, even if scrubbing is performed, the fine particles 3 are hard to be removed. Therefore, even if a part of the fine particles 3 adhered on the surface 2a to be adhered to the back surface 21 of the display glass substrate 1 is dropped due to scrubbing, the surface roughness Ra of about 1 nm .

The manufacturing method of the glass substrate for a display of the present invention is not limited to the above-described method. For example, the coating step, the rinsing step, and the drying step may be carried out by using a manufacturing apparatus equipped with a transporting means, for example, a glass substrate 2 in the direction of the arrow shown in FIG. 5 (a) / Min. &Lt; / RTI &gt;

The production apparatus used in the present embodiment includes, for example, a conveying means including a plurality of conveyance rolls (not shown). As the conveying roll, for example, those vertically arranged in pairs so as to sandwich the glass substrate 2 can be used.

In the present embodiment, the glass substrate 2 is conveyed by the conveying means with the attached surface 2a facing downward.

As shown in Fig. 5A, the manufacturing apparatus used in the present embodiment is provided with a coating liquid tank 41 disposed below the glass substrate 2 being conveyed, and a coating means having a coating roll 42 Respectively. As shown in Fig. 5 (a), a coating liquid 4 containing fine particles 3 is contained in the coating liquid tank 41. As shown in Fig. The coating roll 42 is longer than the width of the glass substrate 2 in the direction perpendicular to the conveying direction of the glass substrate 2 (the direction perpendicular to the conveying direction of the glass substrate 2). As shown in Fig. 5A, the application roll 42 rotates about the rotation axis extending in the direction orthogonal to the conveying direction of the glass substrate 2, in the direction along the conveying direction of the glass substrate 2 .

As shown in Fig. 5 (a), the lower surface of the application roll 42 is in contact with the application liquid 4 contained in the application liquid tank 41. As shown in Fig. The upper surface of the application roll 42 is arranged so as to be in contact with the attached surface 2a of the glass substrate 2 moving in the carrying direction.

5 (a), the coating roll 42 in contact with the glass substrate 2 is rotated in accordance with the movement of the glass substrate 2 to be conveyed, so that the coating roll 42 is brought into contact with the upper surface of the coating roll 42 The coating liquid 4 is supplied onto the attached surface 2a of the glass substrate 2 being moved. Thus, the coating liquid 4 is applied to the adherend surface 2a of the glass substrate 2 (coating step).

The manufacturing apparatus used in the present embodiment is provided with pure water supplying means for supplying pure water 5 by using spray nozzles (not shown) on both the upper and lower surfaces of the glass substrate 2 conveyed by the conveying means. In the pure water supplying means shown in Fig. 5 (b), a plurality of spray nozzles are arranged so as to face each other on the upper and lower surfaces of the glass substrate 2 to be conveyed therebetween.

In this embodiment, the glass substrate 2 coated with the coating liquid 4 is conveyed by the conveying means so that the area where the pure water 5 of the pure water supplying means is supplied as shown in Fig. 5 (b) . As a result, a part of the fine particles 3 present on the attached surface 2a of the glass substrate 2 being conveyed is washed away with pure water 5 (rinsing step). In this embodiment, even if the rinsing step is carried out as shown in Fig. 5 (b), adhesion on the attached surface 2a of the glass substrate 2 due to the difference in surface energy or surface potential The remaining fine particles 3a and 3 remaining on the attached surface 2a of the glass substrate 2 are selectively removed.

5 (b), the pure water 5 is supplied not only to the adhered surface 2a of the glass substrate 2 during transportation but also to the surface 2b in the rinsing step. Further, in the present embodiment, since the glass substrate 2 is conveyed with the attached surface 2a facing downward, the excess fine particles 3a, 3, which are washed out in the rinsing process, are discharged downward. The reason for this is that in the present embodiment, the extra fine particles 3a (3) not attached on the washed surface 2a to be washed out in the rinsing step are attached to the surface 2b of the glass substrate 2 Is effectively prevented.

The manufacturing apparatus used in the present embodiment is provided with drying means (not shown) disposed on the upper and lower sides of the glass substrate 2, respectively. Examples of the drying means include an air knife for ejecting air in the form of a wall along a direction perpendicular to the conveying direction of the glass substrate 2 toward the glass substrate 2, for example.

In the present embodiment, the glass substrate 2 on which the rinsing process has been completed is transported by the transporting means, and is passed through the region where the air is blown in the form of a wall from the air knife as the drying means. As a result, the pure water 5 used in the rinsing step is removed from both sides of the glass substrate 2 being transported (drying step), as shown in Fig. 5 (c).

Example

Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited to these examples.

&Quot; Example 1 &quot;

A glass substrate for display of Example 1 was produced using the following method.

First, as a glass substrate, the glass substrate is cut and formed by the float process, and then the glass substrate is subjected to a roughing treatment for removing the curvature and a cleaning for removing the residue after polishing in order to obtain a glass substrate having both surfaces roughened (manufactured by Asahi Glass Co., : AN100, length 550 mm × width 440 mm × thickness 0.7 mm) was prepared.

Next, 200 ml of a coating liquid containing fine particles was dropped onto the entire surface of the substrate (coating step) on the surface to be adhered to the glass substrate (surface on the side of the back surface of the glass substrate for display).

As the coating liquid, a solution prepared by diluting CE-20A (trade name: manufactured by Nissan Kagaku Co., Ltd.) containing 20 to 21 mass% of ceria particles having an average particle diameter of 8 to 12 nm with pure water to have a ceria content of 0.01 mass% .

Next, as shown in Fig. 3, a rinsing process was performed in which a part of the fine particles on the surface to be adhered was rinsed with pure water. The rinsing process was performed by supplying pure water for 5 seconds at a flow rate of 2000 ml / min using a spray nozzle on the adhered surface of the glass substrate.

Subsequently, the glass substrate on which the rinsing process was finished was dried by using an air blow drying method to remove pure water used in the rinsing process (drying step).

By the above steps, the glass substrate for display of Example 1 was obtained.

The backside roughness Ra of the glass substrate for display of Example 1 was 2.78 nm.

&Quot; Example 2 &quot;

Except that PL-1 (trade name: manufactured by Fuso Chemical Co., Ltd.) containing 12 mass% of silica fine particles having an average particle diameter of 15 nm as an application liquid was diluted with pure water to make a silica content of 0.01 mass% , A glass substrate for display of Example 2 was obtained.

The backside roughness Ra of the glass substrate for display of Example 2 was 5.37 nm.

&Quot; Example 3 &quot;

Except that COMPOL 20 (trade name: manufactured by Fujimi Inc.) containing 40% by mass of silica fine particles having an average particle diameter of 15 nm was diluted with pure water to make a silica content of 0.01% by mass as a coating liquid, 1, a glass substrate for display of Example 3 was obtained.

The backside roughness Ra of the glass substrate for a display of Example 3 was 1.22 nm.

&Quot; Example 4 &quot;

A glass substrate for display of Example 4 was obtained in the same manner as in Example 1 except that a solution in which CE-20A (trade name: manufactured by Nissan Kagaku Co., Ltd.) was diluted with pure water to make a ceria content of 0.1 mass% .

The backside roughness Ra of the glass substrate for display of Example 4 was 4.29 nm.

&Quot; Example 5 &quot;

A glass substrate for display of Example 5 was prepared in the same manner as in Example 1 except that a solution in which CE-20A (trade name: manufactured by Nissan Kagaku Co., Ltd.) was diluted with pure water and the ceria content was 0.001% .

The backside roughness Ra of the glass substrate for display of Example 5 was 1.16 nm.

&Quot; Example 6 &quot;

As a glass substrate, the glass substrates were formed by the float method and cut, and then the surface to be attached was a flame polishing surface (AN100 manufactured by Asahi Glass Co., Ltd., length 550 mm x width 440 mm x thickness 0.7 mm) Similarly, a glass substrate for display of Example 6 was obtained.

The backside roughness Ra of the glass substrate for display of Example 6 was 2.19 nm.

[Example 7]

A glass substrate for display of Example 7 was prepared in the same manner as in Example 6 except that a solution in which CE-20A (trade name: manufactured by Nissan Kagaku Co., Ltd.) was diluted with pure water to give a ceria content of 0.001% .

The backside roughness Ra of the glass substrate for display of Example 7 was 1.47 nm.

&Quot; Example 8 &quot;

The back surface of the glass substrate of Ra = 2.78 nm prepared in Example 1 was subjected to scrubbing for 5 seconds with 2000 ml / min of running water to obtain a glass substrate for display of Example 8.

The backside roughness Ra of the glass substrate for display of Example 8 was 2.46 nm.

&Quot; Example 9 &quot;

The back surface of the glass substrate of Ra = 2.19 nm prepared in Example 6 was scrubbed for 5 seconds with 2000 mL / min of running water to obtain a glass substrate for display of Example 9.

The backside roughness Ra of the glass substrate for display of Example 9 was 0.96 nm.

&Quot; Example 10 &quot;

As in the case of Example 6, except that a solution in which CE-20A (trade name: manufactured by Nissan Kagaku Co., Ltd.) was diluted with a 1/1 (weight ratio) pure water / ethanol solution to a cerium content of 0.01% Thus, a glass substrate for display of Example 10 was obtained.

The backside roughness Ra of the glass substrate for display of Example 10 was 2.94 nm.

&Quot; Example 11 &quot;

As in the case of Example 6, except that a solution in which CE-20A (trade name: manufactured by Nissan Kagaku Co., Ltd.) was diluted with a solution of pure water / glycerin 1/1 (weight ratio) and a ceria content of 0.01 mass% Thus, a glass substrate for display of Example 11 was obtained.

The backside roughness Ra of the glass substrate for display of Example 11 was 2.56 nm.

&Quot; Example 12 &quot;

The same procedure as in Example 6 was carried out except that Snotex AK (trade name: manufactured by Nissan Kagaku Co., Ltd.) was diluted with pure water and the content of the cationic silica was 0.01 mass% To obtain a substrate.

The backside roughness Ra of the glass substrate for a display of Example 12 was 2.16 nm.

&Quot; Example 13 &quot;

The same procedure as in Example 6 was carried out except that a solution in which ultra-fine particle zirconia sol # 1 (trade name: manufactured by Nissan Kagaku Co., Ltd.) was diluted with pure water and the content of zirconia was 0.01 mass% To obtain a substrate.

The backside roughness Ra of the glass substrate for a display of Example 13 was 1.57 nm.

Comparative Example 1

A glass substrate for display of Comparative Example 1 was produced by the following method.

The glass substrate prepared in Example 6 before the application step was used as the glass substrate for display of Comparative Example 1.

The backside roughness Ra of the glass substrate for display of Comparative Example 1 was 0.20 nm.

Next, the peeling electrification amount of the glass substrate for display of Example 6 and Comparative Example 1 was evaluated by the following method.

(Peeling charge amount)

The glass substrate for display was vacuum-adsorbed onto the adsorption stage for a certain period of time, and then peeled off using a lift pin. The voltage between the glass substrate and the adsorption stage, which is caused by electrification occurring when peeling from the adsorption stage, was measured over time.

D is the distance between the glass substrate and the adsorption stage, S is the glass substrate area, and? Is the dielectric constant in the atmosphere, the following equation (1) is obtained: Lt; / RTI &gt;

Since the distance d between the glass substrate and the adsorption stage is expressed by the product of the lift pin lift speed v and the time t, Equation (1) is expressed by the following Equation (2).

The following equation (3) is obtained by time differentiating the equation (2).

Equation (3) shows that the slope of the data obtained by the measurement is proportional to the charge amount. Since the charge amount Q is reduced by the disturbance with the lapse of time, the maximum value of the slope at the moment of peeling is defined as the peeling charge amount.

The peeling electrification amount thus calculated was as low as "0.66" in the case of the comparative example 1 as "1".

Comparative Example 2

A glass substrate for display of Comparative Example 2 was produced by the following method.

The glass substrate before the application step prepared in Example 6 was treated by a method of spraying the abrasive liquid containing the abrasive material described in Patent Document 1 and rubbing with a brush to obtain a glass substrate for display of Comparative Example 2 Respectively.

The backside roughness Ra of the glass substrate for display of Comparative Example 2 was 0.42 nm.

Next, the peeling electrification amount of the glass substrate for display of Example 11 and Comparative Example 2 was evaluated.

The calculated amount of peeling electrification was as low as "0.64" in Example 11 when "1" was taken in Comparative Example 2.

Although the present invention has been described in detail with reference to specific embodiments, it is apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit and scope of the present invention.

This application is based on Japanese Patent Application No. 2012-198825 filed on September 10, 2012, the contents of which are incorporated herein by reference.

The glass substrate for display of the present invention is useful as a substrate of a display such as PDP, LCD, ELD, FED and the like.

1: glass substrate for display
2: glass substrate
2a: attached surface
2b: Surface
3: Particulate matter
4: Coating liquid
5: pure water
21: Back side (one side)
41:
42:

Claims (5)

A glass substrate for display having one surface on which fine particles are adhered on a glass substrate, and an illuminance Ra of 0.5 to 10 nm on the surface. The method according to claim 1,
Wherein the fine particles have an average particle diameter of 50 nm or less. 3. The method according to claim 1 or 2,
Wherein the particulate comprises a metal oxide. 4. The method according to any one of claims 1 to 3,
Wherein the fine particles are one or more selected from ceria fine particles, zirconia fine particles, silica fine particles and alumina fine particles. A manufacturing method of a glass substrate for a display according to any one of claims 1 to 4, comprising: a coating step of applying a coating liquid containing fine particles on one surface of a glass substrate; A rinsing step of rinsing the glass substrate with pure water, and a drying step of drying the glass substrate.

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