KR101194245B1 - Fabricating method of chemical strengthening glass - Google Patents

Abstract

PURPOSE: A manufacturing method of chemically-tempered glass with improved anti-shock strength is provided to prevent manufacturing method of chemically-tempered glass with improved anti-shock strength. CONSTITUTION: A manufacturing method of chemically-tempered glass with improved anti-shock strength previously processes the chemical process before a salt bath strengthening process. The pre-chemical process comprises the following steps: removing foreign materials on the glass surface by processing the glass with an alkaline aqueous solution; removing and performing pre-etching for the residual foreign materials by treating the glass with an acidic aqueous solution; treating the glass with the oxidation acidic aqueous solution; and removing the residual acid. The alkaline degreasing solution composition of the first step comprises 15-30 wt% of alkali metal hydroxide, 1.0-10 wt% of hydrazine or formic acid, 3.0-10 wt% of sorbitol, 1.0-5.0 wt% of gluconic acid, 1.0-5.0wt% of cationic surface active agent, and 50-80 wt% of water. A first etchant composition of the second step comprises 10-30 wt% of sulfuric acid, 20-40 wt% of ammonium fluoride, 1-10 wt% of lead hydrofluoric acid, 15-30 wt% of nitric acid, 0.5-5 wt% of phosphoric acid, 0.1-1.0 wt% of cationic surface active agent and 30-60 wt% of water.

Description

Fabricating method of chemical strengthening glass

The present invention relates to a method for manufacturing chemically strengthened glass, and more particularly, has a higher impact resistance than conventional glass for tempered glass, and even after passing through an etching process, the appearance of glass after tempered glass (Glass) problem It is about how to make glass free.

Along with the rapid spread of smartphones, the demand for touch screen panels is increasing rapidly. In the conventional resistive type using a plastic substrate (Resitive Type) is rapidly switching to a capacitive type smartphone using a tempered glass substrate (tempered glass substrate) is also rapidly increasing demand. Glass for current touch screen panel (Glass) is a chemically strengthened glass is chemically strengthened to increase the mechanical strength to prevent breakage, which is a disadvantage of the glass easily. Chemical strengthening technology performs ion exchange reaction in salt bath (melted potassium nitrate) at 400 ~ 500 ℃ for about 4 ~ 8 hours, so that sodium ion (Na ⁺ ) of glass surface component has large ion radius (K ⁺ It is a technology to improve the glass surface strength by substituting) and it is generalized.

The glass used in the touch screen panel is Corning's aluminosilicate glass "Gorilla Glass" and Soda Lime Glass produced by Ashai Glass, Central, NEG, HOYA and Schott. Corning's "Gorilla Glass", an aluminosilicate glass with more uniform and higher strength properties than soda-lime glass, accounts for more than 70% of the mobile phone cover glass market. Compared with "Gorilla Glass", the application is weak because of the lack of strength characteristics and large quality deviation.

In particular, in order to improve the characteristics of impact strength of soda-lime glass, chemically strengthening the glass after etching a certain thickness of the glass before chemical strengthening (ion exchange), the impact strength of glass, which is a disadvantage of glass, The improvement is widely known as a general technique, but it has not been put to practical use because it does not solve the problem of appearance stain (Tin side stain) that appears in the manufacturing method of soda lime glass.

Due to this problem, the etching process by chemicals before reinforcement is prevented, and instead, it is replaced by primitive mechanical polishing. Mechanical polishing is a manual work performed by manpower, resulting in low productivity and high defect rate, resulting in less than 50% production yield. In addition, because of the mechanical polishing (Polishing) has a problem of deterioration of the work environment due to dust. On the other hand, in terms of quality, when the drop strength of the ball drop is low, the glass is broken by more than 80% when the 130g metal ball is dropped at a height of about 30cm, which has a limit of strength.

Therefore, there is a need for a new technology that can overcome the above problems and limitations.

According to an aspect of the present invention, in the method of manufacturing a tempered glass including a salt bath tempering process, before performing the salt bath tempering process, a chemical pretreatment process is performed, wherein the chemical pretreatment process is performed to remove foreign substances on the glass surface. Alkali degreasing step of treating with an alkaline aqueous solution; A first etching step of treating the glass with an acidic aqueous solution for removing residual impurities and preliminary etching after the alkali degreasing step; A secondary etching step of treating the glass with an oxidizing acidic aqueous solution to etch the glass surface after the first etching step; And a neutralization step for removing residual acid after the secondary etching step.

According to another aspect of the present invention, there is provided an alkali degreasing liquid composition comprising an alkali metal hydroxide, a reducing agent, a degreasing agent, a surfactant and water as the composition used in the above-mentioned alkali degreasing step.

According to another aspect of the present invention, as the composition used in the above-mentioned alkali degreasing step, alkali metal hydroxide 15-30 wt%, hydrazine or formic acid 1.0-10.0 wt%, sorbitol 3.0-10.0 wt%, gluconic acid 1.0-5.0 An alkaline degreasing solution composition is provided comprising wt%, 0.1-1.0 wt% cationic surfactant, and 50-80 wt% water.

According to still another aspect of the present invention, there is provided a composition for use in the above-described first etching step, the composition comprising one or more strong acids selected from the group consisting of sulfuric acid, nitric acid, and phosphoric acid; At least one fluorine-containing acid selected from the group consisting of hydrofluoric acid, boric acid, ammonium fluoride and silicic acid; Surfactants; And water is provided with a primary etchant composition.

According to another aspect of the present invention, the composition used in the above-described primary etching step, 10-30 wt% sulfuric acid, 20-40 wt% ammonium fluoride, 1-10 wt% boric acid, 15-30 wt% nitric acid , A primary etching solution composition comprising 0.5 to 5.0 wt% of phosphoric acid, 0.1 to 1.0 wt% of a cationic surfactant, and 30 to 60 wt% of water is provided.

According to still another aspect of the present invention, there is provided a composition for use in the above-described secondary etching step, the composition comprising one or more strong acids selected from the group consisting of sulfuric acid, nitric acid, and phosphoric acid; At least one fluorine-containing acid selected from the group consisting of hydrofluoric acid, boric acid, ammonium fluoride and silicic acid; Oxidant; Surfactants; And water is provided with a secondary etchant composition.

According to another aspect of the present invention, as the composition used in the above-described secondary etching step, 10-30 wt% sulfuric acid, 1-10 wt% nitric acid, 1-15 wt% ammonium fluoride, 1-15 wt% phosphoric acid, There is provided a secondary etchant composition comprising 1-10 wt% hydrofluoric acid, 1-5 wt% hydrogen peroxide, 0.1-1.0 wt% cationic surfactant, and 40-70 wt% water.

According to another aspect of the invention, the composition used in the above-mentioned neutralization step, potassium hydroxide 1-10 wt%, potassium bicarbonate 10-30 wt%, benzotriazole 1-10 wt%, sodium gluconate 1-10 There is provided a neutralizing liquid composition comprising wt%, 0.1-1.0 wt% cationic surfactant, and 50-80 wt% water.

In order to be used as a substrate for touch screen panels, soda-lime glass with sufficient supply and low original price reduces production quality problems by reducing the quality deviation, which is a problem, and replaces low-productivity mechanical polishing. It is an object of the present invention to develop a chemical having a new pretreatment process and a step-by-step function that does not cause appearance staining problems even by chemical etching.

Soda-lime glass is SiO ₂ (60-75%), Na ₂ O (10-20%), CaO (5-10%) It is composed of components such as Al ₂ O ₃ , K ₂ O and MgO in addition to the main component. Sn) Floating method by floating soda-lime glass on the bed.

The main cause of the appearance stain is contaminated tin (Sn) on the glass side where molten tin is in contact. The surface on which tin (Sn) is contacted contains fluorine, such as hydrofluoric acid (HF), boric acid, ammonium fluoride, and silicic acid, which are commonly used for strong acids such as sulfuric acid, nitric acid, and phosphoric acid, or for free etching. When the acid meets, the stain becomes clear, so that it can be visually identified and the stain remains after chemical strengthening. Of course, if chemical strengthening is performed without etching with hydrofluoric acid (HF) -based chemicals commonly used for strong acid or glass etching, there is no problem of appearance stains, but the strength properties of tempered glass are low, and Due to the wide spread of quality reliability data due to irregular roughness, the yield yield of the desired specification is very low.

According to the present invention there is no problem such as staining of the glass surface without using the hydrofluoric acid (HF) etching solution before the salt bath to improve the impact resistance, it is possible to obtain excellent reinforcing characteristics after the strengthening operation have. To this end, four stages of pretreatment are used before the salt bath is strengthened.

In the conventional window panel fabrication process of portable electronic devices, the original glass uses soda-lime glass to laminate the protective film, cut it to a certain thickness and size, remove (peel) the protective film, clean the surface, and nitric acid. Chemical intensification is carried out by inducing an ion exchange reaction in a salt bath intensifier in which potassium is melted.

In order to achieve the object of the present invention, a new chemical pretreatment process is introduced, unlike the conventional manufacturing process, before the salt bath strengthening (chemical strengthening) as shown in the manufacturing process diagram below.

Conventional Tempered Glass Manufacturing Process Diagram

Tempered glass manufacturing process diagram of the present invention

According to one embodiment of the present invention, a chemical pretreatment process is performed before the salt bath strengthening process of strengthening the glass. The chemical pretreatment process is a core technology of the present invention and may include a four-step chemical treatment process as shown below.

Chemical pretreatment process chart for manufacturing tempered glass of the present invention

In a one-step process, alkaline degreasing is carried out in which the glass is treated with an alkaline aqueous solution to remove foreign matter on the glass surface. In the two step process, after the alkali degreasing step, a primary etching is performed in which the glass is treated with an acidic aqueous solution to remove residual foreign matter and preliminarily etch it. In a three step process, after the first etching step, a second etching is performed to treat the glass with an oxidizing acidic aqueous solution to etch the glass surface. In a four step process, chemical treatment may be performed on the glass surface prior to salt bath strengthening by performing a neutralization step to remove residual acid after the secondary etching step. In some embodiments, a plurality of washing processes may be further included between the steps to prevent mixing of the chemicals between the steps. The alkali degreasing step is performed at 60 to 100 ° C. for at least 10 minutes, and the primary etching step, the secondary etching step, and the neutralization step are preferably performed at 20 to 30 ° C. for 2 to 5 minutes. In the pretreatment process, the composition of the stepwise treatment chemicals for removing the tin-side stain of the soda-lime glass is also different and very important.

The first step is to remove foreign substances remaining on the glass surface while proceeding in an aqueous alkali solution. The alkaline degreasing solution composition (liquid A) used in the alkali degreasing step may include an alkali metal hydroxide, a reducing agent, a degreasing agent, a surfactant, and water. The alkali metal hydroxide may be sodium hydroxide or potassium hydroxide, and the reducing agent may be hydrazine or formic acid. Meanwhile, the degreasing agent may be a saccharide or gluconic acid such as sorbitol.

In a preferred embodiment, the composition of the alkaline degreasing solution (Liquid A) comprises 15-30 wt% of sodium hydroxide (or potassium hydroxide), 1.0-10.0 wt% of hydrazine or formic acid, 3.0-10.0 wt% of sorbitol, 1.0 of gluconic acid. ˜5.0 wt%, 0.1-1.0 wt% of cationic surfactant, and 50-80 wt% of water.

If the sodium hydroxide or potassium hydroxide concentration is less than 15 wt%, it is difficult to remove the tin (Sn) component remaining on the glass surface because the degreasing power is weak, and if it is more than 30 wt%, the surface of the soda lime glass is damaged to improve the transmittance of the glass. Can be reduced.

Hydrazine and other ingredients have a function to help the cleaning effect by improving the wettability of the glass surface, and when used in a large amount, it may cause adverse effects due to foaming and separation of the solution during the cleaning operation.

The degreasing process is carried out at 60-100 ° C. for at least 10 minutes. Effectively, the glass surface was not stained when treated for 30 to 60 minutes at 80 to 100 ° C, and the surface stress and depth of layer, which are the reinforcing properties of the glass, were excellent.

According to one embodiment, three stages of water washing are performed after the first step of alkaline degreasing. In the first washing tank, the first washing tank was impregnated and cleaned for 30 seconds while the pure water was heated to 60 ° C. In the second washing tank, the glass was impregnated and cleaned for 30 seconds in room temperature (20 ~ 30 ℃) and the third was washed at room temperature. (20 ~ 30 ℃) Impregnated and washed with pure water for 30 seconds.

Two-step process is to remove the organic or inorganic, metal oxides on the glass surface that is not removed from the aqueous alkali solution and the alkaline solution. Here, the strong acid solution is also referred to as a primary etching solution, and the primary etching solution composition (B liquid) comprises at least one strong acid selected from the group consisting of sulfuric acid, nitric acid, and phosphoric acid; At least one fluorine-containing acid selected from the group consisting of hydrofluoric acid, boric acid, ammonium fluoride and silicic acid; Surfactants; And water.

In a preferred embodiment, the primary etchant composition (Liquid B) comprises 10-30 wt% sulfuric acid, 20-40 wt% ammonium fluoride, 1-10 wt% boric acid, 15-30 wt% nitric acid, 0.5-5.0 wt% phosphoric acid. It may include 0.1 to 1.0 wt% of cationic surfactant, and 30 to 60 wt% of water.

The primary etching solution composition mainly has a degreasing function rather than an etching function. The thickness etched by the primary etching is adjusted to within 1 μm.

In the primary etching process, the primary etching solution composition (Liquid B) is treated in a dipping state at room temperature (20 to 30 ° C.) for 5 minutes or less. Effectively, the glass surface was not stained when treated at 25 ° C. for 2 minutes, and the longer the treatment time, the lower the transparency of the glass surface.

After the two-stage primary etching process is finished, three stages of water washing are performed. To this end, in the first washing tank of the three-stage washing tank, the glass is impregnated and cleaned for 30 seconds in room temperature (20 ~ 30 ℃) pure water, and in the second washing tank, the pure water is impregnated and washed for 30 seconds while the pure water is heated to 60 ℃ and the third washing tank is In impregnated rinse for 30 seconds at room temperature (20 ~ 30 ℃) pure water.

The three step process is to etch the glass surface with the secondary etching solution. During chemical strengthening, the surface of the glass is etched in order to effectively exchange K ⁺ ions of potassium nitrate with Na ⁺ ions on the glass surface in a potassium nitrate melting tank, and remove contaminants or oxides that have not been removed yet. It is a process to increase the surface area.

The composition (liquid C) of the secondary etching solution includes at least one strong acid selected from the group consisting of sulfuric acid, nitric acid, and phosphoric acid; At least one fluorine-containing acid selected from the group consisting of hydrofluoric acid, boric acid, ammonium fluoride and silicic acid; Oxidant; Surfactants; And water.

In a preferred embodiment, the secondary etchant composition (liquid C) comprises 10-30 wt% sulfuric acid, 1-10 wt% nitric acid, 1-15 wt% ammonium fluoride, 1-15 wt% phosphoric acid, 1-10 wt% hydrofluoric acid, Hydrogen peroxide may include 1 to 5 wt%, cationic surfactant 0.1 to 1.0 wt%, water 40 to 70 wt%.

In the chemical pretreatment step, the secondary etchant composition mainly induces etching of the glass substrate. At this time, the thickness etched by the secondary etching is adjusted to 3 ~ 10㎛. For example, in a secondary etching process, dipping the glass at room temperature 25 ° C. for 2-5 minutes results in 3-10 micron (μm) etching of the glass surface. If the processing time is longer than 5 minutes, the etching amount increases and the surface becomes rough, which causes wave appearance, causing appearance defects. If the etching time is less than 2 minutes, there is no appearance defect, but micro-roughness formation is insufficient, so it is difficult to expect the effect due to the surface area during chemical strengthening.

Immediately after the impregnation operation in the secondary etching tank, the chemicals are cleaned in a three-stage washing tank. In the first washing tank, impregnated and cleaned glass for 30 seconds at room temperature (20 ~ 30 ℃), in the second washing tank, impregnated and cleaned for 30 seconds while heating pure water to 60 ℃, and in the third washing tank, room temperature (20 ~ 30 ℃) ) Impregnated pure water for 30 seconds.

The four step process is a process of neutralizing residual acid (Acid) by the strong acid treatment in three steps. Even traces of residual acid continually corrode the glass surface, causing surface appearance stains. In a preferred embodiment, the composition of the neutralizing nucleus (liquid D) comprises 1-10 wt% of potassium hydroxide, 10-30 wt% of potassium bicarbonate, 1-10 wt% of benzotriazole, 1-10 wt% of sodium gluconate, and cationic surfactant 0.1 to 1.0 wt%, water may include 50 to 80 wt%.

The neutralization process can be carried out by dipping the glass in the neutralizing solution for 2-5 minutes at room temperature. At this time, if the neutralization liquid treatment time is less than 2 minutes, the residual acid treatment may be insufficient to cause secondary contamination of the glass surface. If the treatment time exceeds 5 minutes, staining of the glass surface by the alkaline component may occur. Effectively, 2-3 minutes is appropriate at room temperature.

In order to explain the present invention in detail, examples and comparative examples are given, but the following examples are intended to illustrate the present invention and are not limited to the claims.

Of chemical pretreatment Example  And Comparative example

1) Composition A Example Comparative Example A1 A2 A3 1 2 Sodium hydroxide 25 X X 40 20 Potassium hydroxide X 30 20 X 20 Hydrazine 8 5 10 X X Sorbitol 3 5 10 X X Gluconic Acid 1.5 2 3 X X Cationic Surfactants 0.5 0.5 0.5 0.5 0.5 Pure water (H ₂ O) 62 57.5 56.5 59.5 59.5 Sum 100 100 100 100 100

2) B composition Example Comparative Example B1 B2 B3 Me1 Me2 Sulfuric acid (61.5%) 30 20 30 15 10 Ammonium Fluoride 15 10 5 X X Boric acid 5 2 One 5 10 nitric acid 10 15 10 5 7 Phosphoric Acid 3.5 2 5 X X Cationic Surfactants 0.5 0.5 0.5 0.5 0.5 Pure water (H ₂ O) 36 50.5 48.5 74.5 72.5 Sum 100 100 100 100 100

3) C composition Example Comparative Example C1 C2 C3 C1 2 Sulfuric acid 20 25 15 20 X nitric acid 5 5 10 X 20 Ammonium Fluoride 10 5 15 X 2 Phosphoric Acid 5 3 10 10 5 Foshan 5.5 8.5 3.5 15 10 Hydrogen peroxide 2 1.0 3.0 X X Cationic Surfactants 0.5 0.5 0.5 X Pure water (H ₂ O) 52 52 43 55 63 Sum 100 100 100 100 100

4) D composition Example Comparative Example D1 D2 D3 La1 2 Potassium hydroxide 5 10 3 20 X Potassium bicarbonate 20 15 25 X 35 Benzotriazole 3.5 2.0 7 X X Sodium Gluconate 3 1.5 2 X X Cationic Surfactants 0.5 0.5 0.5 0.5 0.5 Pure water (H ₂ O) 68 71 62.5 79.5 64.5 Sum 100 100 100 100 100

After cutting the soda-lime glass in the 4.3-inch size with a protective film, the edge was processed finely with a 600 ~ 800 mesh grinding wheel. The soda lime glass was chemically pretreated in the following process for final ultrasonic cleaning. Subsequently, the chemical strengthening furnace (KNO ₃ melting tank) was cooled and cleaned after 430 x 4 hours of strengthening, and then physical properties of the tempered glass were checked.

Chemical pretreatment process chart

* Examples and Comparative Examples of Chemical Pretreatment Processes Yes A amount B amount C amount D amount Chemical Pretreatment Process Example 1 A1 B1 C1 D1 Process all steps 1, 2, 3 and 4 Example 2 A2 B2 C2 D2 Process all steps 1, 2, 3 and 4 Example 3 A3 B3 C3 D3 Steps 2, 3, 4 are all processed. Comparative Example 1 A1 B1 X D1 Skip only the 3-step process and proceed with the rest Comparative Example 2 X B2 C2 D2 Skip only the first step and proceed with the rest Comparative Example 3 X X C3 D3 Skip steps 1 and 2 and proceed Comparative Example 4 X X C1 X Only 3-step secondary etching process Comparative Example 5 1 Me1 C1 La1 Process all steps 1, 2, 3 and 4 Comparative Example 6 2 Me2 2 2 Process all steps 1, 2, 3 and 4 Comparative Example 7 X X C1 X Only 3-step secondary etching process Comparative Example 8 X X 2 X Only 3-step secondary etching process

* After hardening work (430 ℃, 4 hours hardening in potassium nitrate melting tank), the result of reinforcing properties (soda lime glass 0.7T thickness, external polishing (700mesh), area: 70X110 mm ² ) Glass surface appearance Surface stress
(Mpa) DOL
(Μm) Bending strength
3-axis breaking load Ball Drop Strength (cm) Tin (sn) side stain Surface wave transparency Example 1 ○ ○ ○ 665.8 11.3 29.5 kgf 80 Example 2 ○ ○ ○ 645.3 12.6 27.8 kgf 90 Example 3 ○ ○ ○ 672.1 9.5 32.1 kgf 70 Comparative Example 1 ○ ○ △ 590.7 10.2 26.5 kgf 40 Comparative Example 2 X ○ △ 570.6 10.6 25.7 kgf 80 Comparative Example 3 X ○ △ 557.3 8.3 29.5 kgf 60 Comparative Example 4 X ○ △ 550.7 9.8 27.8 kgf 50 Comparative Example 5 △ X X 577.2 10.5 24.1 kgf 50 Comparative Example 6 △ △ X 540.9 9.2 26.5 kgf 40 Comparative Example 7 X X X 530.1 7.3 27.1 kgf 30 Comparative Example 8 X △ X 534.5 8.5 24.4 kgf 40

* Experimental Evaluation Standard (Toughened Glass)

  1) Glass surface appearance

    -Visually judge the glass surface (stain, wave, transparency) state in the dark room by the light of 3 wavelength fluorescent light (Appearance: Good, Normal, Bad X)

  2) surface stress

    -Surface stress measurement with tempered glass surface stress meter (Orihara Industrial.co-FSM-6000LE, Japan)

  3) Reinforcement Layer Depth (DOL)

    -Glass surface reinforced layer depth is measured by surface stress measuring instrument (Orihara Industrial.co-FSM-6000LE, Japan)

  4) 3-axis bending strength-UK, LLOYD's LF Plus Bending Tester measures maximum load (kgf) of breaking strength under speed (10 mm / min) and span (40 mm)

  5) Ball Drop Strength

-Fix the glass specimen on the jig and measure the height (cm) that is broken by descending to a steel ball (130g) at a certain height.

(evaluation)

As a result of introducing the four-step chemical pretreatment process according to the present invention before the glass salt strengthening, the problem of staining of the glass surface generated during etching of soda-lime glass, as distinguished from the examples and the comparative examples, was improved and strengthened. The physical properties of the tempered glass was also able to secure excellent values.

Comparative Example 1 From The results of Comparative Example 4 may be omitted, only one step in a pre-processing step 4, even if applied to both the pre-processing step of step 4 from the result of Comparative Example 5 lack the appearance properties of the glass, and Example 6 pre-treatment If the composition of the drug is different, the strengthening properties were insufficient.

In particular, when looking at the height of the ball drop (130g steel ball), which is the property of fracture strength, it is possible to secure excellent properties that do not break even at the height of 70 ~ 80cm than the height of 20 ~ 40cm that conventional tempered glass can withstand. It has the effect of suggesting the possibility of lowering the thickness of tempered glass.

As described above, when another chemical pretreatment process is used in the present invention, tempered glass having excellent mechanical properties without staining problems may be obtained.

Claims (12)

In the manufacturing method of tempered glass comprising a salt bath strengthening step,
Before the salt bath strengthening process is carried out a chemical pretreatment process,
The chemical pretreatment process includes an alkali degreasing step of treating the glass with an alkaline aqueous solution to remove foreign substances on the glass surface;
A first etching step of treating the glass with an acidic aqueous solution for removing residual impurities and preliminary etching after the alkali degreasing step;
A secondary etching step of treating the glass with an oxidizing acidic aqueous solution to etch the glass surface after the first etching step; And
And a neutralization step for removing residual acid after the secondary etching step. The method according to claim 1,
The alkali degreasing step proceeds for at least 10 minutes at 60 ~ 100 ℃, the primary etching step, the secondary etching step, and the neutralizing step is proceeding for 2 to 5 minutes at 20 ~ 30 ℃. The method according to claim 1,
The thickness of the etching by the primary etching method of manufacturing tempered glass is adjusted to within 1㎛. The method according to claim 1,
The thickness of the etching by the secondary etching method of manufacturing a tempered glass is adjusted to 3 ~ 10㎛. 5. The method according to any one of claims 1 to 4,
Method for producing tempered glass further comprises a plurality of washing step between each step. delete delete delete As the composition used in the first etching step of the method of manufacturing a tempered glass according to claim 1,
Sulfuric acid 10-30 wt%, ammonium fluoride 20-40 wt%, boric acid 1-10 wt%, nitric acid 15-30 wt%, phosphoric acid 0.5-5.0 wt%, cationic surfactant 0.1-1.0 wt%, and water 30- A primary etchant composition comprising 60 wt%. delete As a composition used in the secondary etching step of the method of manufacturing a tempered glass according to claim 1,
Sulfuric acid 10-30 wt%, nitric acid 1-10 wt%, ammonium fluoride 1-15 wt%, phosphoric acid 1-15 wt%, hydrofluoric acid 1-10 wt%, hydrogen peroxide 1-5 wt%, cationic surfactant 0.1-1.0 wt%, and a secondary etchant composition comprising 40 to 70 wt% of water. As the composition used in the neutralizing step of the method of manufacturing a tempered glass according to claim 1,
Potassium hydroxide 1-10 wt%, potassium bicarbonate 10-30 wt%, benzotriazole 1-10 wt%, sodium gluconate 1-10 wt%, cationic surfactant 0.1-1.0 wt%, and water 50-80 wt% Neutralizing liquid composition comprising a.