KR102207188B1 - Low-emissivity glass - Google Patents

Abstract

The present invention includes a form in which a glass substrate, a first dielectric layer, a first metal protective layer, an infrared reflective metal layer, a second metal protective layer, a second dielectric layer, and an overcoat layer are sequentially stacked, and a* value is -4 to 1 And b* value is -15 or less, and the first metal protective layer and the second metal protective layer have a thickness ratio of 1: 0.5 to 0.6, and relates to a low-emission glass.

Description

Low-emission glass {LOW-EMISSIVITY GLASS}

The present invention relates to a low-emission glass exhibiting excellent durability and a strong blue surface.

Low-emission glass deposits a metal with high reflectivity in the infrared region, such as silver (Ag), on a transparent glass to maintain the transparency of the glass, while preventing the indoor heating heat from leaking out in winter and the sun entering the room in summer. It refers to a functional building material that reflects radiant heat. Low-emission glass has been limitedly used in non-residential buildings with a large glass construction area, but recently, as the need for energy saving has increased, the case of application to residential buildings is increasing, and the demand for low-emission glass with suitable properties is increasing.

In particular, in the case of low-emission glass used in non-residential buildings, superior insulation and shielding performance and excellent appearance are required instead of high visible light transmittance, whereas low-emission glass used in residential buildings preferentially has high visible light transmittance for viewing. Is required. In addition, compared to the low-emission glass used in non-residential buildings, the glass used in residential buildings is used in a large amount, so it is necessary to ensure excellent durability at a level that can be distributed in many places.

On the other hand, the structure of the low-emission glass manufactured by the sputtering method includes an infrared reflective metal layer, and generally includes a dielectric layer above and below the metal layer to protect the infrared reflective metal layer. However, in the case of depositing a dielectric layer on the infrared reflecting metal layer, since the metal is used as a target material in an oxygen or nitrogen atmosphere, the infrared reflecting metal layer is oxidized or nitrided by oxygen or nitrogen injected into the chamber, and the interlayer between the infrared reflecting metal layer and the dielectric layer There is a problem of blurring the boundaries. In addition, due to the ambiguity of the interlayer boundary as described above, there is a problem in that the emissivity value of the manufactured glass increases, thereby losing the characteristics of the low-emission glass.

As an alternative to this, U.S. Patent No. 6,804,048 (Patent Document 1) includes a first undercoat layer including a dielectric material, an infrared reflective layer, and a second undercoat layer including a dielectric material, including a heat treatment capable of having a multilayer structure. Low-emission glass is disclosed. However, since the low-emissivity glass of Patent Document 1 is weak in chemical durability and thus easily damages the coating film, there is a disadvantage in that fogging (haze) occurs in the coating film during a heat treatment or bending process.

In addition, Korean Registered Patent No. 215,380 (Patent Document 2) includes a transparent non-metallic substrate, an antireflective base film containing zinc-tin oxide, a metallic film containing silver (Ag) and reflecting infrared rays, and zinc oxide. A coating product including a crystalline metal contact film portion to reduce fogging during heat treatment is disclosed. However, in the case of the coating product of Patent Document 2, when the coating film is exposed to the outside for a long time due to the weak durability of the zinc-based oxide of the coating layer located above and below the metallic film, the metallic film may be damaged.

Therefore, there is a need for research and development on low-emission glass having excellent chemical and mechanical durability and excellent visible light transmittance.

U.S. Patent No. 6,804,048 (published on November 20, 2003) Korean Patent Registration No. 215,380 (published on October 26, 1998)

Accordingly, the present invention is to provide a low-emissivity glass having a strong blue surface, excellent chemical and mechanical durability, and low emissivity.

The present invention includes a form in which a glass substrate, a first dielectric layer, a first metal protective layer, an infrared reflective metal layer, a second metal protective layer, a second dielectric layer, and an overcoat layer are sequentially stacked, and a* value is -4 to 1 And b* value is -15 or less, and the first metal protective layer and the second metal protective layer have a thickness ratio of 1: 0.5 to 0.6, providing a low-emissivity glass.

The low-emission glass according to the present invention has a strong blue surface, excellent chemical and mechanical durability before and after heat treatment, and low emissivity. For this reason, the low-emission glass is suitable as a building material for residential buildings and non-residential buildings.

Hereinafter, the present invention will be described in detail.

In the present invention, the'a* value' and'b* value' of the glass are measured according to the KS L 2514 standard using a D65 standard light source in a wavelength range of 380 to 780 nm based on an average thickness of a glass substrate of 6 mm. It means the a* value and b* value of the surface.

The low-emission glass according to the present invention includes a glass substrate, a first dielectric layer, a first metal protective layer, an infrared reflective metal layer, a second metal protective layer, a second dielectric layer, and an overcoat layer sequentially stacked, and a* value Is -4 to 1, b* value is -15 or less, and the thickness ratio of the first metal protective layer and the second metal protective layer is 1:0.5 to 0.6.

Glass substrate

As the glass substrate, ordinary glass such as soda-lime glass used for construction or automobiles can be used.

Further, as the glass substrate, glass having an appropriate thickness may be used depending on the purpose of use. For example, as the glass substrate, a transparent soda lime glass having an average thickness of 2 to 12 mm, or 5 to 6 mm may be used.

First dielectric layer and second dielectric layer

Each of the first dielectric layer and the second dielectric layer serves to protect the infrared reflective metal layer from ions or oxygen during heat treatment and to adjust the optical properties of the manufactured glass.

Each of the first dielectric layer and the second dielectric layer may include at least one selected from the group consisting of nitride and nitride oxide. Specifically, each of the first dielectric layer and the second dielectric layer may include silicon-containing nitride. More specifically, the first dielectric layer and the second dielectric layer may each include SiAlN _x or Si _y N _z , wherein x is an integer of 1 to 3, y is 2 or 3, and z is 3 or May be 4.

Furthermore, each of the first dielectric layer and the second dielectric layer may have a refractive index of 1.8 to 2.5 and an absorption coefficient of 0.1 or less. Specifically, each of the first dielectric layer and the second dielectric layer may have a refractive index of 1.8 to 2.2 and an absorption coefficient of 0 to 0.1. When the refractive index and absorption coefficient of each of the first dielectric layer and the second dielectric layer are within the above ranges, it is possible to prevent a problem in that the visible light transmittance of the manufactured glass is decreased.

In addition, each of the first dielectric layer and the second dielectric layer may have an average thickness of 50 to 70 nm. When the average thickness of each of the first dielectric layer and the second dielectric layer is within the above range, it is possible to prevent a problem in that the durability of the manufactured glass is deteriorated and a problem in which the blue color of the surface is decreased.

First metal protective layer and second metal protective layer

The first metal protective layer and the second metal protective layer improve the adhesion between the infrared reflective metal layer and the dielectric layer, prevent the movement of Na diffused from the glass and oxygen (O ₂ ) in the air during heat treatment, and the infrared reflecting metal layer It plays a role in helping the fusion of the infrared reflective metal to enable stable behavior even at high heat treatment temperatures, and helps maintain the low radiation performance of the glass by absorbing oxygen (O ₂ ) penetrating into the infrared reflecting metal layer.

Each of the first metal protective layer and the second metal protective layer may include one or more selected from the group consisting of nickel (Ni), chromium (Cr), and nickel (Ni)-chromium (Cr) alloys. Specifically, each of the first metal protective layer and the second metal protective layer may include a nickel (Ni)-chromium (Cr) alloy. In this case, the nickel (Ni)-chromium (Cr) alloy may include 75 to 85% by weight of nickel and 15 to 25% by weight of chromium based on the total weight of the alloy.

Further, each of the first metal protective layer and the second metal protective layer may have an average thickness of 4 to 20 nm. Specifically, each of the first metal protective layer and the second metal protective layer may have an average thickness of 4 to 10 nm. When the average thickness of each of the first metal protective layer and the second metal protective layer is within the above range, the durability and/or visible light transmittance of the manufactured glass decreases, and the problem of increasing the haze of the coating film after heat treatment and bending process is prevented. can do.

The first metal protective layer and the second metal protective layer have a thickness ratio of 1: 0.5 to 0.6. When the thickness ratio of the first metal protective layer and the second metal protective layer is within the above range, it is possible to prevent a problem of lowering the durability of the manufactured glass and a problem of reducing a blue color of the glass surface. In particular, when the thickness ratio of the first metal protective layer and the second metal protective layer is maintained within the above range, the manufactured glass may have an appropriate absorption rate.

Infrared reflective metal layer

The infrared reflecting metal layer serves to realize low radiation while providing high shielding performance of the glass manufactured by selectively reflecting the sun's radiation.

The infrared reflective metal layer may include a metal having excellent conductivity, and may include, for example, at least one metal selected from the group consisting of gold, silver, platinum, aluminum, and copper. Specifically, the infrared reflecting metal layer may include silver (Ag). More specifically, the infrared reflecting metal layer may be made of silver.

In addition, the average thickness of the infrared reflecting metal layer may be 10 to 15 nm. When the thickness of the infrared reflecting metal layer is within the above range, the problem of insufficient low-emissivity performance of the manufactured glass due to the formation of the infrared reflecting metal layer is not performed normally, and the problem of lowering the blue color of the glass surface due to the high reflectance of the manufactured glass. Can be prevented.

Overcoat layer

The overcoat layer serves to protect the second dielectric layer and the infrared reflecting metal layer.

The overcoat layer may include a material having high mechanical strength, low surface roughness, and high visible light transmittance. For example, the overcoat layer may include silicon (Si), niobium (Nb), titanium (Ti), zirconium (Zr), tantalum (Ta), or an alloy, oxide, nitride, or nitride oxide thereof. Specifically, zirconium-containing oxide or nitride, or titanium-containing oxide or nitride oxide may be included as the overcoat layer. In this case, the titanium-containing nitride oxide may be, for example, TiO _x N _y , where x and y may be a molar ratio of 100:0 to 75:25 based on 100 mol% of the sum of x and y.

In addition, the average thickness of the overcoat layer may be 2 to 15 nm. When the average thickness of the overcoat layer is within the above range, it is possible to prevent a problem in that durability of the manufactured glass is deteriorated, and a problem in which fogging occurs after heat treatment of the manufactured glass.

The low-emission glass according to the present invention has an a* value of -4 to 1, and a b* value of -15 or less. Specifically, the low-emission glass may have an a* value of -3 to 1, and a b* value of -30 to -18.

Furthermore, the low-emissivity glass may have an emissivity of 0.2 or less, or 0.1 or less. Emissivity refers to the ratio of energy that is partially re-emitted after absorbing external light energy or re-radiated when surface reflection occurs.The maximum value is 1, and the smaller the value, the higher the ratio of energy re-emitted or re-radiated. it means.

The low-emission glass according to the present invention as described above has a strong blue surface, and has excellent chemical and mechanical durability both before and after heat treatment. For this reason, the low-emission glass is suitable as a building material for residential buildings and non-residential buildings.

The low-emission glass according to the present invention may be manufactured using a vacuum sputtering method as a thin film forming method for forming each layer. That is, the method of manufacturing a low-emission glass according to the present invention may include forming each layer by a sputtering deposition method.

Hereinafter, the present invention will be described in more detail through examples. However, these examples are only intended to aid understanding of the present invention, and the scope of the present invention is not limited to these examples in any sense.

[Example]

Examples 1 to 11 and Comparative Examples 1 to 13. Preparation of low-emission glass

The thickness of each layer was adjusted and laminated as described in Tables 1 and 2. Specifically, the first dielectric layer was coated on a 6mm-thick transparent glass substrate in a nitrogen and argon atmosphere using a SiAl rotary target. Thereafter, a first metal protective layer was coated on the first dielectric layer using a NiCr Planar target in an argon atmosphere, and an infrared reflective metal layer was coated on the first metal protective layer using an Ag Planar target in an argon atmosphere. Thereafter, a second metal protective layer was coated on the infrared reflective metal layer using a NiCr Planar target in an argon atmosphere. Thereafter, the second dielectric layer was coated on the second metal protective layer using a SiAl rotary target in a nitrogen and argon atmosphere, and finally, an overcoat layer was coated on the second dielectric layer using a Zr rotary target in an argon and nitrogen atmosphere. A low-emission glass was prepared.

(Thickness nm) Overcoat layer Second dielectric layer Second metal protective layer Infrared reflection
Metal layer First metal
Protective layer First dielectric layer Example 1 7 60 4 12 8 60 Example 2 7 60 4.8 12 8 60 Example 3 7 60 5 12 10 60 Example 4 7 60 6 12 10 60 Example 5 10 60 4 12 7 60 Example 6 7 65 4 10 6.7 55 Example 7 8 50 4.4 11 8 50 Example 8 8 70 4.4 14 8 70 Example 9 2 60 4.4 11 8 60 Example 10 8 60 4.4 12 8 60 Example 11 15 60 4.4 13 8 60

(Thickness nm) Overcoat layer Second dielectric layer Second metal
Protective layer Infrared reflective metal layer First metal
Protective layer First dielectric layer Comparative Example 1 7 60 1.4 12 3 60 Comparative Example 2 7 60 1.9 12 3 60 Comparative Example 3 7 60 3 12 3 60 Comparative Example 4 7 40 6 12 10 40 Comparative Example 5 7 45 6 12 10 45 Comparative Example 6 7 48 6 12 10 48 Comparative Example 7 7 72 6 12 10 72 Comparative Example 8 7 75 6 12 10 75 Comparative Example 9 7 80 6 12 10 80 Comparative Example 10 0 60 6 12 12 60 Comparative Example 11 One 60 6 12 14 60 Comparative Example 12 16 60 9 12 20 60 Comparative Example 13 18 60 15 12 20 60

Test Example: Evaluation of properties of glass

The physical properties of the low-emission glasses prepared in Examples 1 to 11 and Comparative Examples 1 to 13 were measured in the following manner, and the results are shown in Table 3.

Specifically, the low-emission glass prepared in Examples and Comparative Examples was heat-treated at 650° C. for 5 minutes and then quenched, and then the physical properties were evaluated.

(1) the color of the glass surface

In a wavelength range of 380 to 780 nm, a 10° reflection color of the glass surface was measured according to the KS L 2514 standard using a D65 standard light source.

(2) sheet resistance

Sheet resistance was measured using a surface resistance meter (non-contact type sheet resistance meter, manufactured by SURAGUS). The sheet resistance of glass is a value measured by a silver (Ag) layer, which is an infrared reflecting metal layer targeting solar rays, and is one of the evaluation properties that can measure its performance as a low-emission glass even after heat treatment.

(3) scratch resistance

After spraying distilled water mixed with quartz powder on the coated surface of the manufactured glass, a 0.5mm-thick nylon brush was moved back and forth horizontally 200 times with the coated surface of the glass, and the number of scratches generated on the coated surface was measured. Evaluated.

Specifically, if there is no scratch, grade 1, if less than 5 scratches less than 1 mm wide are generated, grade 2, if there are 5 or more scratches less than 1 mm wide, grade 3, thicker than 1 mm wide If one or two scratches were generated, it was rated as 4, when three or more thick scratches of 1 mm or more in width were generated, it was rated as 5, and if the coating film was peeled from the glass substrate, it was rated as 6th.

(4) moisture resistance

The prepared low-emission glass was stored at 30° C. and 80% relative humidity for 7 days, and then the number of pinholes generated on the surface of the overcoat layer was measured to evaluate moisture resistance.

(5) haze

Haze was evaluated by visually observing the degree of blurring of the surface of the overcoat layer after heat treatment of the prepared low-emission glass.

(6) Emissivity

The emissivity was calculated based on the KS L 2525 standard by measuring the reflection spectrum in the infrared wavelength region (2,500 to 25,000 nm) using FT-IR after heat treatment of the low-emissivity glass.

(7) visible light transmittance

For the visible light transmittance, after heat treatment of the low-emission glass, the transmission spectrum of the visible light wavelength region (380 to 780 nm) was measured using a spectrophotometer (Spectrophotometer, Rambda950, manufactured by Perkinelmer), and was calculated according to the KS L 2514 standard.

division Color of the glass surface Sheet resistance
(Ω/sq) Nask
Latchability Moisture resistance
(Number of pinholes) Haze Emissivity Visible light
Transmittance
(%) Y L a* b* practice
Example 1 15.8 46.7 -0.2 -20.5 7 Level 2 none none 0.081 54.8 Example 2 17.6 49.0 -0.9 -20.1 7 Level 2 none none 0.081 53 Example 3 18.0 49.5 -1.1 -20.0 7 Level 2 none none 0.081 51 Example 4 20.4 52.3 -1.8 -19.8 7 Level 2 none none 0.081 47 Example 5 15.3 46.0 -0.7 -22.5 7 Level 2 none none 0.081 54.3 Example 6 14.7 45.2 -0.2 -21 8 Level 2 none none 0.095 56 Example 7 15.6 46.4 0.0 -20.5 7.5 Level 2 none none 0.088 54.8 Example 8 18.0 49.5 -1.2 -20.7 6 Level 2 none none 0.068 51 Example 9 13.8 43.9 -0.4 -20.0 7.5 Level 2 none none 0.088 56.5 Example 10 15.6 46.5 -1.3 -20.0 7 Level 2 none none 0.081 54 Example 11 19.2 50.9 -2.9 -19.7 6.5 Level 2 none none 0.075 50.1 compare
Example 1 11.8 40.9 3.1 -18.8 7 Level 6 10 things Occur 0.081 57.5 Comparative Example 2 13.0 43 2.2 -20.5 7 Level 5 5 pieces Occur 0.081 57.3 Comparative Example 3 15.5 46.3 1.1 -21.3 7 Level 3 Three Fine occurrence 0.081 55.1 Comparative Example 4 16.6 47.8 1.4 -0.5 7 Level 3 none Occur 0.081 54.6 Comparative Example 5 17.5 48.9 0.9 -5.0 7 Level 3 none Occur 0.081 53.4 Comparative Example 6 18.4 50.0 0.5 -7.8 7 Level 3 none Occur 0.081 52.4 Comparative Example 7 35.4 66.1 -7.8 -10.3 7 Level 2 none Occur 0.081 40.1 Comparative Example 8 38.6 68.4 -8.6 -7.4 7 Level 2 none Occur 0.081 38.3 Comparative Example 9 42.1 70.9 -8.9 -3.1 7 Level 2 none Occur 0.081 35.8 Comparative Example 10 24.6 56.7 -2.5 -14.2 7 Level 5 10 things Occur 0.081 46.2 Comparative Example 11 25.1 57.2 -2.8 -14.7 7 Level 5 10 things Occur 0.081 46.1 Comparative Example 12 14 44.4 1.5 -14.2 7 Level 2 none Occur 0.081 56.7 compare
Yes 13 17.5 49 1.2 -8.3 7 Level 2 none Occur 0.081 42.3

As shown in Table 3, the low-emission glass of Examples 1 to 11 has a low sheet resistance of 9 Ω/sq or less after heat treatment, excellent durability such as moisture resistance and scratch resistance, and haze of the coating film occurs due to heat treatment. Without doing so, the glass surface had a strong blue color, and showed a high visible light transmittance of 47% or more.

On the other hand, Comparative Examples 1 to 3 in which the thickness of the first metal protective layer and the second metal protective layer were thin were insufficient in moisture resistance, and haze occurred in the coating film after heat treatment. In particular, Comparative Examples 1 and 12 in which the thickness ratio of the first metal protective layer and the second metal protective layer was less than 0.5 had a problem in that red color increased as the a* value of the glass surface was greater than 1.1. In addition, Comparative Examples 2, 3, and 13 in which the thickness ratio exceeded 0.6 did not exhibit strong blue color. In addition, in Comparative Examples 4 to 9 in which the first dielectric layer and/or the second dielectric layer are thin or thick, the b* value of the glass surface is greater than -11, so that strong blue color is reduced. Further, in Comparative Examples 10 to 13 having a thin or thick overcoat layer, haze was generated after heat treatment, and thus durability was insufficient. In particular, Comparative Examples 10 and 11 having a thin or no overcoat layer were remarkably insufficient in scratch resistance and moisture resistance after heat treatment.

Claims (4)

A glass substrate, a first dielectric layer, a first metal protective layer, an infrared reflective metal layer, a second metal protective layer, a second dielectric layer and an overcoat layer are sequentially stacked,
The overcoat layer includes zirconium nitride,
The first dielectric layer has an average thickness of 50 to 70 nm,
The first metal protective layer has an average thickness of 4 to 20 nm,
The infrared reflecting metal layer has an average thickness of 10 to 15 nm,
The second metal protective layer has an average thickness of 4 to 20 nm,
The second dielectric layer has an average thickness of 50 to 70 nm,
The overcoat layer has an average thickness of 2 to 15 nm,
a* value is -4 to 1, b* value is -15 or less, and the first metal protective layer and the second metal protective layer have a thickness ratio of 1: 0.5 to 0.6, low-emission glass. delete The method according to claim 1,
Each of the first dielectric layer and the second dielectric layer includes at least one selected from the group consisting of nitride and nitride oxide, has a refractive index of 1.8 to 2.5, and an absorption coefficient of 0.1 or less. The method according to claim 1,
The first metal protective layer and the second metal protective layer each contain at least one selected from the group consisting of nickel, chromium, and nickel-chromium alloy, low-emission glass.