KR20110018069A - Transparent substrate having multilayer coating for anti-reflection and method for preparing the same - Google Patents

Abstract

PURPOSE: A transparent substrate having a multi coasting layer and a manufacturing method thereof, capable of enhancing mechanical property are provided to reduce the defect generation rate of a product. CONSTITUTION: A multi coating layer for anti-reflection includes a first high refractive layer, a first low refractive layer, a second high refractive layer and a second refraction layer. The first high refractive layer and the second high refractive layer include chemical formula AxOyNz. The first low refractive layer and the second low refractive layer include silicon oxide and silicon oxynitride. The high refractive layer includes the titanium oxide(TiO2). The low refractive layer comprises the silicon oxynitride.

Description

Transparent substrate having anti-reflective multilayer coating and its manufacturing method {TRANSPARENT SUBSTRATE HAVING MULTILAYER COATING FOR ANTI-REFLECTION AND METHOD FOR PREPARING THE SAME}

The present invention relates to a transparent substrate having an antireflection multilayer coating and a method of manufacturing the same, and more particularly, a first high refractive layer coated sequentially on a transparent substrate; A first low refractive layer; A second high refractive layer; And a second low refractive index layer, which has excellent mechanical properties such as abrasion resistance and chemical resistance, and has a low reflection transparent substrate and excellent productivity that significantly lowers antireflection even when exposed to harsh conditions. It is about how it can be.

The function of the antireflective coating deposited on a transparent substrate such as glass is to reduce the reflection of light and thus increase the light transmission. Thus, in the case of a substrate to which such an antireflective coating is applied, the transmission / reflection light ratio is increased, thereby improving visibility of an object located behind the substrate. In order to further enhance the antireflection effect, it is desirable to provide antireflective coatings of this function on both sides of the substrate.

In addition, anti-reflective coatings, for example, when applied to a picture-protective glass substrate, make the picture illuminated by the light behind the observer more vivid, and when applied to a store window glass, even when the interior light is darker than the exterior light. It can be used for a variety of purposes, such as to more clearly distinguish what is in the store. (E.g. show window, car showroom, museum, solar cell, etc.)

The performance of the antireflective coating can be measured or evaluated according to several criteria. The first criterion is, of course, optical characteristics. In order for an antireflective coating to be considered 'good', it should be possible to reduce the light reflection of the transparent standard glass substrate to a given value or less, for example 1.5%, or more preferably 1% or less.

Anti-reflective coatings, which are used as windows in buildings and automobiles, consist of a multi-layered structure comprising thin interferential layers deposited on a substrate. In general, a layer having a higher refractive index and a layer having a lower refractive index alternates. It is.

Examples of antireflective coatings are described in EP 0728712 and WO 97/43224. These prior literatures have suggested glass substrates / SnO ₂ / SiO ₂ / Bi ₂ O ₃ / SiO ₂ or glass substrates / SnO ₂ / SiO ₂ / WO ₃ / SiO ₂ film structures as examples of antireflective coatings, and have a high refractive index. SnO ₂ , Bi ₂ O ₃ , WO ₃ , and the like are used as the film, and SiO ₂ is used as the low refractive index film. Meanwhile, Korean Patent Application No. 10-2004-7013717 discloses a glass substrate / Si ₃ N ₄ / SiO ₂ / Si ₃ N ₄ / SiO ₂ or a glass substrate / SnO ₂ / SiO ₂ / SnO ₂ / SiO ₂ film as an antireflective coating. The structure is presented.

However, most of the recent antireflective coatings, including those set forth in the preceding documents, focus only on optimizing to minimize light reflection at normal incidence, and to provide mechanical resistance such as wear resistance and It does not take into account the ability to withstand external conditions that occur in actual use, such as chemical resistance, nor does it take into account productivity. As a result, it exhibits excellent anti-reflective properties equivalent to those of conventional anti-reflective coatings, and at the same time, has excellent mechanical properties and chemical resistance such as wear resistance, so that the anti-reflective coating having a significant decrease in anti-reflective properties even when exposed to severe conditions and glass having the same on the surface The demand for transparent substrates is increasing.

The present invention has been made to solve the problems of the prior art as described above, and exhibits excellent anti-reflective properties and at the same time excellent mechanical properties and chemical resistance, such as abrasion resistance, significantly less antireflection even when exposed to severe conditions antireflection multilayer It is a technical problem to provide a transparent substrate having a coating and a method of manufacturing the same.

The present invention to solve the above technical problem, the first high refractive index layer sequentially coated on a transparent substrate; A first low refractive layer; A second high refractive layer; And a second low refractive index layer comprising at least one surface of an antireflection multilayer coating, wherein the first and second high refractive layers are represented by the formula A _x O _y N _z (A = Ti, Nb, Zn, Sn, Al or alloys thereof; x = 1 to 2; y = 1 to 5; z = 0 to 3) comprising a material independently selected from the group consisting of oxides or nitride oxides of the metal, said first And the second low refractive index layer includes a material independently selected from the group consisting of silicon oxide and silicon nitride oxide, wherein the low refractive index layer comprises silicon nitride oxide when the high refractive index layer includes titanium oxide (TiO ₂ ). It provides a low reflection transparent substrate.

In addition, according to another aspect of the invention, on at least one side of the transparent substrate, the first high refractive layer; A first low refractive layer; A second high refractive layer; And sequentially coating a second low refractive layer by sputtering, wherein the first and second high refractive layers are represented by the formula A _x O _y N _z (A = Ti, Nb, Zn, Sn, Al). Or alloys thereof; x = 1 to 2; y = 1 to 5; z = 0 to 3), and a material independently selected from the group consisting of oxides or nitrides of metals, wherein the first and second The low refractive index layer includes a material independently selected from the group consisting of silicon oxide and silicon nitride oxide, and if the high refractive layer includes titanium oxide (TiO ₂ ), the low refractive layer includes silicon nitride, low reflection transparent A method of manufacturing a substrate is provided.

According to the present invention, it exhibits excellent anti-reflective property by reducing the reflectance of vertical incident visible light to 1.5%, preferably 1.0%, and is significantly superior in mechanical properties and chemical resistance such as abrasion resistance compared to the previously developed film structure. Even if exposed to the bottom, a transparent substrate having an antireflective multilayer coating having a markedly low antireflection can be easily manufactured economically and with excellent productivity. More specifically, according to the present invention has the following effects.

First, productivity can be improved because the deposition rate of the high and low refractive layers can be increased while maintaining or improving the low reflection characteristics.

Second, as the deposition rate of the film increases, the power applied to the sputter to form a predetermined thickness is lowered, thereby reducing the defect occurrence rate of the product.

Third, because the mechanical properties and chemical resistance of the low reflection coating substrate, such as abrasion resistance is remarkably excellent, the low reflection quality can be maintained for a long time even if the coating film is exposed to the outside.

Referring to the features of each component layer included in the low reflection transparent substrate according to the present invention in detail.

First of all, as the transparent substrate, a transparent material such as a glass substrate, an acrylic substrate, a polycarbonate substrate, and the like can be used without limitation as long as the anti-reflective multilayer coating according to the present invention can be formed on the surface thereof, and a glass substrate is preferably used. do. As the glass substrate, conventional glass such as soda-lime glass for construction or automobile can be used without limitation. In addition, the glass having a thickness of 2mm ~ 10mm can be used freely depending on the purpose of use.

The first and second high refractive layers are of the formula A _x O _y N _z (A = Ti, Nb, Zn, Sn, Al or alloys thereof; x = 1 to 2; y = 1 to 5; z = 0 to 3) It includes a material independently selected from the group consisting of an oxide or a nitride oxide of a metal represented by, preferably titanium oxide, titanium nitride oxide or niobium oxide may be used independently.

The high refractive index layer preferably has a refractive index of 2.0 or more and 3.0 or less, more preferably 2.2 or more and 2.5 or less, given the desired level of low reflection properties and the range of refractive indices of the available high refractive layer material.

In order to maintain the low reflection performance at a desired level, the thickness of the first high refractive layer is preferably in the range of 5 to 15 nm, more preferably in the range of 8 to 12 nm, and the thickness of the second high refractive layer is preferably It is the range of 80-120 nm, More preferably, it is the range of 90-110 nm.

The first and second low refractive layers include a material independently selected from the group consisting of silicon oxide (SiO ₂ ) and silicon nitride oxide, and the low refractive layer is nitrided if the high refractive layer includes titanium oxide (TiO ₂ ). Silicon oxide. If the high refractive index layer is a titanium oxide (TiO ₂ ) layer, if the low refractive layer is a silicon oxide layer, as shown in Comparative Example 1 below, productivity, mechanical properties, chemical resistance, etc. are not satisfactory. In addition, silicon with 0 to 20% by weight of Al may be used as a target material for forming a low refractive index in order to increase conductivity.

The low refractive index layer preferably has a refractive index of 1.0 or more and less than 2.0, preferably 1.4 or more and 1.8 or less, given the desired level of low reflection properties and the range of refractive indices of available low refractive layer materials.

In order to maintain the low reflection performance at a desired level, the thickness of the first low refractive index layer is preferably in the range of 20 to 40 nm, more preferably in the range of 25 to 35 nm, and the thickness of the second low refractive layer is preferable. Preferably it is the range of 60-100 nm, More preferably, it is the range of 70-90 nm.

In addition to the above-described functional layers, the low reflection transparent substrate of the present invention may further include functional layers conventionally adopted for the low reflection transparent substrate within a range capable of achieving the object of the present invention. In addition, the low reflection transparent substrate of the present invention may include two or more multi-layered structures including the series of functional layers described above sequentially from the substrate surface. When two or more of the multilayer structures are included, they may be repeatedly stacked on one surface of the substrate, or alternatively, may be laminated on both surfaces of the substrate, respectively. Therefore, according to one embodiment of the present invention, as shown in Fig. 1, a low reflection transparent substrate having the antireflection multilayer coating described above on both sides of the substrate is provided. The low reflection transparent substrate of such a double-sided coating may be prepared by coating both sides of a single substrate, or may be obtained by bonding substrates coated with only one side.

Thus, according to one embodiment of the invention, the low reflection transparent substrate of the present invention is silicon nitride / titanium nitride / silicon nitride / titanium nitride / substrate / titanium nitride / silicon nitride / titanium nitride / nitride It has a film structure of silicon oxide.

According to another embodiment of the present invention, the low reflection transparent substrate of the present invention is a film of silicon oxide / niobium oxide (Nb ₂ O ₅ ) / silicon oxide / niobium oxide / substrate / niobium oxide / silicon oxide / niobium oxide / silicon oxide Has a structure.

According to another embodiment of the present invention, the low reflection transparent substrate of the present invention is a film structure of silicon nitride oxide / titanium oxide / silicon nitride oxide / titanium oxide / substrate / titanium oxide / silicon nitride oxide / titanium oxide / silicon nitride oxide Has

The low-reflective transparent substrate of the present invention exhibits excellent anti-reflective properties, and also has excellent mechanical properties and chemical resistance such as wear resistance, so that the anti-reflective property is significantly lowered even when exposed to harsh conditions. Suitable.

The low reflection transparent substrate of the present invention includes: a first high refractive layer on at least one surface of the transparent substrate; A first low refractive layer; A second high refractive layer; And sequentially coating a second low refractive layer by sputtering, wherein the first and second high refractive layers are represented by the formula A _x O _y N _z (A = Ti, Nb, Zn, Sn, Al or Alloys thereof; x = 1 to 2; y = 1 to 5; z = 0 to 3), a material independently selected from the group consisting of oxides or nitrides of metals, wherein the first and second low The refractive layer includes a material independently selected from the group consisting of silicon oxide and silicon nitride oxide, and if the high refractive layer includes titanium oxide (TiO ₂ ), the low refractive layer includes silicon nitride. Can be prepared.

According to one embodiment of the present invention, the sequential coating described above may be performed on both sides of the transparent substrate to prepare a low reflection transparent substrate.

As a method of coating a material having a high refractive index or a low refractive index on a transparent substrate such as glass, a wet method (sol-gel method), a hard coating method, and a soft coating method are known. In the wet method, there is a disadvantage that the durability and chemical resistance of the coating is weakened, and there is a problem that it is difficult to coat a large area, such as for construction. In the case of the hard coating method, there is a limitation in the applicable materials and a poor reflectance performance. Therefore, the present invention is characterized by coating a high refractive index layer and a low refractive index layer by a soft coating method, that is, sputtering. In the case of coating by the sputtering method, there is an advantage that the coating can be performed with a uniform film thickness over a large area.

According to one embodiment of the invention, the low reflection transparent substrate of the present invention is a magnetron (Cylindrical-Magnetron, C-Mag) sputter coating machine (for example, coating equipment of von ardenn or bekaert Co., Ltd. can be used) according to the vacuum sputtering method. Can be prepared by the following procedure. First, the substrate is placed in a vacuum chamber and evacuated until the degree of vacuum becomes 5 × 10 ⁻⁷ to 9 × 10 ⁻⁵ torr to form a vacuum. When argon (Ar), oxygen (O ₂ ), nitrogen (N ₂ ) gas, etc. are introduced into the vacuum chamber, a discharge occurs when a direct current or an alternating voltage is applied between the two electrodes. As gas ions collide with a cathode provided with a metal target to be stacked, atoms are released from the metal target and stacked on a substrate. An appropriate gas is introduced according to the type of coating film to be laminated, and the thickness of the coating film to be formed is appropriately controlled by appropriately adjusting the moving speed of the substrate, the deposition rate of each coating film, and the time exposed to the sputtering process. The temperature of the substrate is not particularly limited.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the scope of protection of the present invention is not limited by these examples.

[Example]

5 tons of commercially available building soda-lime glass were used to prepare the low-reflective coated glass of Examples and Comparative Examples. Magnetron sputtering equipment commonly used for construction was used to deposit the desired coating film.

Titanium oxide, titanium nitride or niobium oxide was used as a high refractive index coating film, and a target material for coating the coating was Ti or Nb, and the refractive index and deposition rate of the film were adjusted by appropriately adjusting the argon, nitrogen, and oxygen gas atmospheres. Changed.

Silicon oxide or silicon nitride oxide was used as the low refractive index coating film, and Si [Si: Al target with 10wt% Al added to improve conductivity] was used as a target material for coating the film. Argon, nitrogen and oxygen gas were used. The atmosphere was properly adjusted to change the refractive index and deposition rate of the film.

Since the refractive index of the single film is required for the thickness design of the low reflection coating film, first, the characteristics of the single film, that is, the deposition rate and the refractive index according to the gas atmosphere were obtained, and the results are shown in Table 1 below.

Example 1

Coating was performed in a magnetron sputtering coating apparatus with Ti and Si targets under an atmosphere having an Ar / N ₂ / O ₂ ratio of 30/40/30 to prepare a low reflection coating glass having a film structure as follows (coating Thickness: unit nm):

Silicon Nitride (80) / Titanium Nitride (100) / Silicon Nitride (30) / Titanium Nitride (10) / Substrate / Titanium Nitride (10) / Silicon Nitride (30) / Titanium Nitride (100) Silicon Nitride (80)

Example 2

Coating was performed in a magnetron sputtering coating apparatus with Nb and Si targets under an atmosphere having an Ar / O ₂ ratio of 20/80 to prepare a low reflection coating glass having a film structure as follows (coating thickness of each layer is Same as Example 1):

Silicon oxide / niobium oxide / silicon oxide / niobium oxide / substrate / niobium oxide / silicon oxide / niobium oxide / silicon oxide

Example 3

Coating was carried out in a magnetron sputtering coating apparatus with a Ti target under an atmosphere with an Ar / O ₂ ratio of 20/80 and a Si target under an atmosphere with an Ar / N ₂ / O ₂ ratio of 30/40/30. A low reflection coating glass was prepared having the following film structure (coating thickness of each layer was the same as that of Example 1):

Silicon Nitride / Titanium Oxide / Silicon Nitride / Titanium Oxide / Substrate / Titanium Oxide / Silicon Nitride Oxide / Titanium Oxide / Silicon Nitride

Comparative Example 1

Coating was performed in a magnetron sputtering coating apparatus with Ti and Si targets under an atmosphere having an Ar / O ₂ ratio of 20/80 to prepare a low reflection coated glass having a film structure as follows (coating thickness of each layer Is the same as Example 1):

Silicon oxide / titanium oxide / silicon oxide / titanium oxide / substrate / titanium oxide / silicon oxide / titanium oxide / silicon oxide

Comparative Example 2

In the magnetron sputtering coating equipment, silicon oxide (SiO ₂ ) is deposited on an Si target under an atmosphere of 20/80 in an Ar / O ₂ ratio, and a silicon target under an atmosphere in which an Ar / N ₂ ratio is 20/80. Silicon nitride oxide (Si ₃ N ₄ ) was deposited to prepare a low reflection coating glass having the following film structure (coating thickness of each layer is the same as in Example 1):

Silicon Oxide / Silicon Nitride Oxide / Silicon Oxide / Silicon Nitride Oxide / Substrate / Silicon Nitride Oxide / Silicon Oxide / Silicon Nitride Oxide / Silicon Oxide

In preparing the coated glass as in Examples 1 to 3 and Comparative Examples 1 to 2, the line speed required for sample production in order to set the visible light reflectance to 1% or less is shown in Table 2 below.

As can be seen in Table 2, Examples 1 to 3 of the low reflection coating glass according to the present invention increased the line speed by about 70% compared to the comparative example. That is, according to the present invention, it is possible to manufacture a coating glass having an excellent low reflection effect (low visible light reflectance of 1% or less) or more than the equivalent level compared to the prior art (comparative example) with an increased productivity of about 70%.

On the other hand, the wear resistance test, acid / base resistance test and constant temperature and humidity test were performed on the glass samples prepared according to the above Examples and Comparative Examples according to the following method. The results of measuring the transmittance before and after each test are shown in Table 3 below.

Abrasion resistance test: Taber Abraser Model 5150 was used in reference to KS L 2014 Heat Reflective Glass Specification, and two 500g weights were loaded and then rotated 500 times using CS-10F wear wheel. .

Acid Resistance Test: The treatment was performed for 48 hours in 1N HCl solution referring to the KS L 2014 Heat Reflective Glass Specification.

-Base resistance test: treated for 6 hours in 1N NaOH solution referring to the KS L 2014 heat reflecting glass specifications.

Constant temperature and humidity test: Treatment was performed for 3 weeks in a chamber maintained at 50 ° C. 90% RH. This test is an accelerated endurance test that can compare and confirm long-term durability in a short time.

As can be seen in Table 3, it can be seen that the coating glass of Examples 1 to 3 according to the present invention is about two times better in all of the wear resistance, acid resistance, base resistance, and constant temperature and humidity resistance than the comparative example.

1 is a view schematically showing a layer structure of a low reflection transparent substrate having antireflection multilayer coating of the present invention on both sides of a substrate according to one embodiment of the present invention.

[Description of Symbols in Drawing]

A: first high refractive layer

B: first low refractive layer

C: second high refractive layer

D: second low refractive layer

glass: glass substrate

Claims (11)

A first high refractive index layer sequentially coated on the transparent substrate; A first low refractive layer; A second high refractive layer; And a second low refractive index layer comprising at least one surface of an antireflection multilayer coating, wherein the first and second high refractive layers are represented by the formula A _x O _y N _z (A = Ti, Nb, Zn, Sn, Al or alloys thereof; x = 1 to 2; y = 1 to 5; z = 0 to 3) comprising a material independently selected from the group consisting of oxides or nitride oxides of the metal, said first And the second low refractive index layer includes a material independently selected from the group consisting of silicon oxide and silicon nitride oxide, wherein the low refractive index layer comprises silicon nitride oxide when the high refractive index layer includes titanium oxide (TiO ₂ ). Low reflection transparent substrate. The low reflection transparent substrate according to claim 1, wherein the transparent substrate is a glass substrate, an acrylic substrate or a polycarbonate substrate. The low reflection transparent substrate according to claim 1, wherein the high refractive index layer has a refractive index of 2.0 or more and 3.0 or less. The low reflection transparent substrate according to claim 1, wherein the thickness of the first high refractive layer is 5 to 15 nm and the thickness of the second high refractive layer is 80 to 120 nm. The low reflection transparent substrate according to claim 1, wherein the low refractive index layer has a refractive index of 1.0 or more and less than 2.0.        The low reflection transparent substrate according to claim 1, wherein the thickness of the first low refractive index layer is 20 to 40 nm, and the thickness of the second low refractive index layer is 60 to 100 nm. The low reflection transparent substrate according to claim 1, wherein the antireflection multilayer coating is provided on both surfaces of the substrate. 8. The low film according to claim 7, which has a film structure of silicon nitride / titanium nitride / silicon nitride / titanium nitride / substrate / titanium nitride / silicon nitride / titanium nitride / silicon nitride. Reflective transparent substrate. The low reflection transparency according to claim 7, which has a film structure of silicon oxide / niobium oxide (Nb ₂ O ₅ ) / silicon oxide / niobium oxide / substrate / niobium oxide / silicon oxide / niobium oxide / silicon oxide. Board. The low reflection transparent substrate according to claim 7, characterized in that it has a film structure of silicon nitride oxide / titanium oxide / silicon nitride oxide / titanium oxide / substrate / titanium oxide / silicon nitride oxide / titanium oxide / silicon nitride oxide. . A first high refractive index layer on at least one side of the transparent substrate; A first low refractive layer; A second high refractive layer; And sequentially coating a second low refractive layer by sputtering, wherein the first and second high refractive layers are represented by the formula A _x O _y N _z (A = Ti, Nb, Zn, Sn, Al or Alloys thereof; x = 1 to 2; y = 1 to 5; z = 0 to 3), a material independently selected from the group consisting of oxides or nitrides of metals, wherein the first and second low The refractive layer includes a material independently selected from the group consisting of silicon oxide and silicon nitride oxide, wherein the low refractive index layer comprises silicon nitride when the high refractive layer comprises titanium oxide (TiO ₂ ). Manufacturing method.

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