KR101228093B1 - Etching glass - Google Patents

Abstract

The present invention relates to an etching glass in which a porous layer is homogeneously formed on the surface of a substrate while increasing the etching rate and transmittance. The etching glass according to the present invention is a porous layer through etching on a surface of a glass substrate. Wherein, the glass substrate includes silicon oxide (SiO ₂ ) and aluminum oxide (Al ₂ O ₃ ) as a main component, the weight ratio of aluminum (Al) to silicon (Si) is 0.3 or more, 0.8 or less, etching reaction The time is characterized in that less than 10 minutes.

Description

Etching glass

The present invention relates to etched glass, and more particularly, to an etched glass in which a porous layer is homogeneously formed on the surface of a substrate while increasing the etching rate and transmittance.

Recently, development of high efficiency photovoltaic modules has been carried out on a large scale in order to prevent energy resources and environmental pollution. Photovoltaic modules are key elements in photovoltaic power generation that directly convert light energy, such as solar energy, into electricity.

The transmittance of the cover substrate used for the protection of the crystalline photovoltaic module and the superstrate substrate of the thin film photovoltaic module, such as the glass substrate, affects the overall efficiency of the photovoltaic module. Conventionally, many developments have been made to improve transmittance such as forming a porous layer through etching on a glass substrate surface to minimize reflectance to improve transmittance.

Such etched glass is used as cover glass for display to increase the brightness. In general, the transmittance and luminance have a proportional relationship. That is, the transmittance of each wavelength passing through the etching glass is equal to the value obtained by dividing the luminance of each wavelength passed by the bare luminance of each wavelength. In addition, refresh rates must be available from 120Hz to 480Hz, and the development of high-transmittance etched glass at the time of the introduction of 3D TVs will greatly improve the performance of high brightness displays.

However, when forming a porous layer (etched) on the surface of the glass substrate has a problem that takes a long time. In order to solve this problem, if the reaction temperature is raised to about 60 ° C. or more, the reaction time is reduced, but the porous layer is not uniform on the surface of the substrate, and staining occurs, which causes a problem of lowering the transmittance.

The present invention has been proposed in the above background, and an object of the present invention is to provide an etching glass having a high etching rate and a high transmittance and a homogeneous porous layer formed on the substrate surface.

In order to achieve the above object, the etching glass according to an aspect of the present invention is a porous layer (Porous Layer) is formed on the surface of the glass substrate, wherein the glass substrate is silicon oxide (SiO ₂ ) and aluminum oxide ( Al ₂ O ₃ ) as a main component, the weight ratio of aluminum (Al) to silicon (Si) is 0.3 or more, 0.8 or less, characterized in that the etching reaction time is 10 minutes or less.

Etched glass according to an additional aspect of the invention, the glass substrate is at least magnesium oxide (MgO), calcium oxide (CaO), sodium oxide (Na ₂ O), potassium oxide (K ₂ O), or antimony oxide (Sb ₂ O ₃ ) as an auxiliary component, the content of silicon oxide (SiO ₂ ) is more than 53.0 wt.%, 63.0 wt.% Or less, the content of aluminum oxide (Al ₂ O ₃ ) is 10.0 wt.% 20.0 wt.% Or less, magnesium oxide (MgO) content of 0.0 wt.% Or more, 6.50 wt.% Or less, calcium oxide (CaO) content of 6.8 wt.% Or more and 9.81 wt.% Or less , The content of sodium oxide (Na ₂ O) is 13.4 wt.% Or more, 18.23 wt.% Or less, the content of potassium oxide (K ₂ O) is 0.0 wt.% Or more, 0.38 wt.% Or less, and antimony oxide ( Sb ₂ O ₃ ) is characterized in that the content of more than 0.0 wt.%, 0.16 wt.% Or less.

The etched glass according to another additional aspect of the present invention is characterized by having a transmittance of 97% or more, a density of 2.5 or more, 2.6 or less, and a coefficient of thermal expansion (CTE) of 90 or more and 112 or less.

Etching glass of the present invention configured as described above, the silicon oxide (SiO ₂ ) content of the glass substrate used for etching and increase the content of aluminum oxide (Al ₂ O ₃ ), sodium oxide (Na ₂ O), By changing the contents of potassium oxide (K ₂ O), magnesium oxide (MgO), calcium oxide (CaO), and antimony oxide (Sb ₂ O ₃ ), a porous layer is formed on the surface of the glass substrate while increasing the etching rate. It forms a homogeneously and has a useful effect that can satisfy the basic physical properties of the etched glass.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the present embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout.

In the present invention, the glass substrate is mainly composed of silicon oxide (SiO ₂ ) and aluminum oxide (Al ₂ O ₃ ), optionally magnesium oxide (MgO), calcium oxide (CaO), sodium oxide (Na ₂ O), potassium oxide (K ₂ O), and antimony oxide (Sb ₂ O ₃ ) is implemented.

In a glass substrate mainly composed of silicon oxide (SiO ₂ ), the breakdown of the ≡Si-O bond having the strongest bonding force determines the etching rate. That is, when the bonding force of Si-O is reduced, the etching rate of the glass substrate is increased. As the content of silicon oxide (SiO ₂ ) decreases and the content of sodium oxide (Na ₂ O), potassium oxide (K ₂ O), magnesium oxide (MgO) and calcium oxide (CaO) increases, the etching rate increases. . In addition, when Non Bridging Oxygen (NBO) is increased in the glass substrate structure, the ring structure of Si-O-Si is broken, thereby reducing the network connectivity and increasing the etching rate.

In the case of Alkali Silicate glass substrates, sodium oxide (Na ₂ O), potassium oxide (K ₂ O), magnesium oxide (MgO), and calcium oxide (CaO) combine with non-bridging oxide (NBO), but aluminum (Al) in its structure When added, aluminum (Al) has a tetrahedral configuration like silicon (Si) and acts as a structural modifier to generate [AlO ₄ ]-excess electrons. At this time, sodium oxide (Na ₂ O), potassium oxide (K ₂ O), magnesium oxide (MgO) and calcium oxide (CaO) are combined with [AlO ₄ ]-which is stronger than Non Bridging Oxygen (NBO). When one aluminum (Al) is added, one non-bridging oxygen (NBO) is destroyed.

In general basic or neutral conditions, the movement of sodium (Na) or potassium (K), which has the largest mobility among glass substrate components, is prevented, and ≡Si-O is separated by the addition of aluminum (Al). In order to make the structure more dense, the diffusion of the etching solution is disadvantageous and the chemical durability is increased.

However, under acidic conditions, especially under strong acid conditions such as the etching solution of the present invention, aluminum (Al) exhibits a completely different property, and hydrolysis of Al-O-Si is promoted by H + to give ≡Si-O-Si. All components except for VIII are selectively etched to act to increase the etch rate. The increase in the etching rate due to the addition of aluminum oxide (Al ₂ O ₃ ) is because the ring structure is broken and a gap is formed in the structure, which facilitates the diffusion of H + and fluoride, which are the main etching components.

Thus, the present inventors reduce the content of silicon oxide (SiO ₂ ) in the composition of the glass substrate and increase the content of aluminum oxide (Al ₂ O ₃ ), while improving the transmittance and increase the etching rate of the existing soda lime (Soda- lime) A composition range was developed to satisfy the properties of glass substrate level. That is, the content of silicon oxide (SiO ₂ ) is reduced and the content of aluminum oxide (Al ₂ O ₃ ) is increased, but sodium oxide (Na ₂ O), potassium oxide (K ₂ O) and magnesium oxide (MgO), and oxidation The contents of calcium (CaO) and antimony oxide (Sb ₂ O ₃ ) were changed. The content of aluminum oxide (Al ₂ O ₃ ) in the etching glass composition was adjusted to increase the ratio of Si-O-Al and Al-O-Al bonds other than Si-O, which is liable to be selectively etched under etching solution conditions.

In order to determine the degree of etching efficiency increase by the glass substrate composition simulation mainly comprising silicon oxide (SiO ₂ ) and aluminum oxide (Al ₂ O ₃ ) of the present invention, an etching solution immersion experiment was carried out for each composition of the glass substrate. It was confirmed whether the etching rate increased. In the etching method used in the present invention, silicon oxide (SiO ₂ ) and aluminum oxide (Al ₂ O ₃ ) are produced by supersaturating silicon oxide (SiO ₂ ) in a solution of silicic acid fluoride (H ₂ SiF ₆ ) to produce H ₂ SiF ₆ · SiF 4. The method of selectively etching the remaining components except for the strong bonding strength of the glass substrate structure having the main component as ≡Si-O-Si≡ was used.

wt.% Comparative example Example One 2 3 4 5 6 One 2 3 4 SiO ₂ 72.67 68.06 67.06 66.06 65.06 64.06 63.06 62.06 61.06 60.06 Al ₂ O ₃ 0.54 5.00 6.00 7.00 8.00 9.00 10.00 11.00 12.00 13.00 MgO 4.31 5.31 5.21 5.12 6.01 7.84 6.50 5.94 4.62 3.84 CaO 8.86 7.86 7.91 7.82 6.94 7.84 6.86 6.92 7.81 5.43 Na ₂ O 13.23 13.61 13.66 13.84 13.83 14.73 13.42 13.92 14.35 17.51 K ₂ O 0.38 - - - - - - - - - Sb ₂ O ₃ - 0.16 0.16 0.16 0.16 0.16 0.16 0.16 0.16 0.16 Temperature 1358.5 1358.6 1358.5 1358.4 1358.9 1358.7 1358.8 1358.4 1358.2 1358.8 Distortion point 506.3 524.8 527.2 531.1 540.8 543.8 545.7 540.5 540.2 538.8 density 2.489 2.503 2.511 2.519 2.521 2.524 2.526 2.537 2.542 2.548 CTE 85.59 89.79 89.62 90.12 90.45 90.12 90.11 92.58 95.44 100.89 Al / Si 0.015 0.147 0.179 0.212 0.246 0.281 0.317 0.354 0.393 0.433 NBO
The presence or absence ○ ○ ○ ○ ○ ○ ○ ○ ○ ○ Transmittance 97% 97% 97% 97% 97% 97% 97% 97% 97% 97% etching
time
45 minutes
30 minutes
22 minutes
18 minutes
14 minutes
11 minutes
9 minutes
7 minutes
5 minutes
3 minutes wt.% Example 5 6 7 8 9 10 11 SiO ₂ 59.06 58.06 57.06 56.06 55.06 54.06 53.06 Al ₂ O ₃ 14.00 15.00 16.00 17.00 18.00 19.00 20.00 MgO 1.87 0.09 0.05 - - - - CaO 6.90 8.08 8.13 9.12 9.54 9.35 9.81 Na ₂ O 18.01 18.23 18.22 17.28 16.86 17.05 16.59 K ₂ O - 0.38 0.38 0.38 0.38 0.38 0.38 Sb ₂ O ₃ 0.16 0.16 0.16 0.16 0.16 0.16 0.16 Temperature 1358.9 1358.2 1358.5 1358.1 1358.9 1358.7 1358.5 Distortion point 536.4 535.4 530.7 526.2 511.9 503.4 492.7 density 2.552 2.559 2.54 2.534 2.531 2.527 2.523 CTE 105.11 107.18 108.45 109.54 110.81 111.54 111.95 Al / Si 0.474 0.517 0.561 0.606 0.654 0.703 0.754 NBO
The presence or absence ○ ○ ○ ○ ○ ○ ○ Transmittance 97% 97% 97% 97% 97% 97% 97% etching
time
2 minutes
30 seconds
15 seconds
15 seconds
5 seconds
5 seconds
5 seconds

As shown in Examples 1 to 11 of Table 1, the content (wt.%) Of silicon oxide (SiO ₂ ) is reduced by 1.0 wt.%, And the content (wt.%) Of aluminum oxide (Al ₂ O ₃ ). Is increased by 1.0 wt.%, And sodium oxide (Na ₂ O), potassium oxide (K ₂ O), magnesium oxide (MgO), calcium oxide (CaO), The content (wt.%) Of antimony oxide (Sb ₂ O ₃ ) was changed.

As a result, when the content (wt.%) Of aluminum oxide (Al ₂ O ₃ ) in the glass substrate composition is 10 wt.% Or more and the weight ratio of aluminum (Al) to silicon (Si) is 0.317 or more, the reaction is performed under an etching condition of 45 ° C. The results were within 10 minutes. However, when the content of aluminum oxide (Al ₂ O ₃ ) in the glass substrate composition is excessively increased, the high temperature viscosity of the etched glass becomes high, so that melting becomes difficult. Therefore, it is preferable to have a range of 10.0 wt.% Or more and 20.0 wt.% Or less.

As shown in Table 1, preferably, the glass substrate has a silicon oxide (SiO ₂ ) content of at least 53.0 wt.%, 63.0 wt.% Or less, and an aluminum oxide (Al ₂ O ₃ ) content of 10.0 wt.%. 20.0 wt.% Or less, magnesium oxide (MgO) content of 0.0 wt.% Or more, 6.50 wt.% Or less, calcium oxide (CaO) content of 6.8 wt.% Or more and 9.81 wt.% Or less , The content of sodium oxide (Na ₂ O) is 13.4 wt.% Or more, 18.23 wt.% Or less, the content of potassium oxide (K ₂ O) is 0.0 wt.% Or more, 0.38 wt.% Or less, and antimony oxide ( Sb ₂ O ₃ ) is implemented in the range of 0.0 wt.% Or more and 0.16 wt.% Or less.

In addition, in Table 1, the etched glass according to Examples 1 to 11 shows similar ranges of physical properties such as the etched glass according to Comparative Examples 1 to 6, such as transmittance, density, thermal expansion coefficient (CTE), and presence or absence of on bridging oxide (NBO). have.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention as defined by the appended claims. Accordingly, the true scope of the present invention should be determined only by the appended claims.

Claims (5)

An etching glass in which a porous layer is formed on the surface of a glass substrate through etching,
The glass substrate includes silicon oxide (SiO ₂ ) and aluminum oxide (Al ₂ O ₃ ),
The content of the silicon oxide (SiO ₂ ) is 53.0 wt.% Or more, 63.0 wt.% Or less,
The content of the aluminum oxide (Al ₂ O ₃ ) is 10.0 wt.% Or more, 20.0 wt.% Or less,
Etching glass, characterized in that the etching reaction time of the glass substrate is less than 10 minutes. The method of claim 1,
The glass substrate includes at least one of magnesium oxide (MgO), calcium oxide (CaO), sodium oxide (Na ₂ O), potassium oxide (K ₂ O), or antimony oxide (Sb ₂ O ₃ ) as an auxiliary component. But
The content of magnesium oxide (MgO) is 0.0 wt.% Or more, 6.50 wt.% Or less,
The content of calcium oxide (CaO) is 6.8 wt.% Or more, 9.81 wt.% Or less,
The content of sodium oxide (Na ₂ O) is 13.4 wt.% Or more, 18.23 wt.% Or less,
The content of potassium oxide (K ₂ O) is 0.0 wt.% Or more, 0.38 wt.% Or less,
The content of the antimony oxide (Sb ₂ O ₃ ) is 0.0 wt.% Or more, 0.16 wt.% Or less, etching glass. The method of claim 1,
The transmittance | permeability of the said etching glass is 97% or more, The etching glass characterized by the above-mentioned. The method of claim 1,
Density of the said etching glass is 2.5 or more and 2.6 or less, The etching glass characterized by the above-mentioned. The method of claim 1,
The thermal expansion coefficient (CTE) of the said etching glass is 90 * 10 <^-7> / degreeC or more, and 112 * 10 <^-7> / degrees C or less, The etching glass characterized by the above-mentioned.