KR101975637B1

KR101975637B1 - Low Emissivity Glass

Info

Publication number: KR101975637B1
Application number: KR1020160088392A
Authority: KR
Inventors: 강현민; 오영훈; 윤윤희
Original assignee: 주식회사 케이씨씨
Priority date: 2016-07-13
Filing date: 2016-07-13
Publication date: 2019-05-07
Also published as: KR20180007424A; WO2018012883A1

Abstract

The present invention relates to a low emissivity glass having a emissivity of 0.01 to 0.03 and a visible light transmittance of 40% or more and realizing a neutral color by including a dual functional reflective metal layer having a specific thickness ratio.

Description

{Low Emissivity Glass}

The present invention relates to a low emissivity glass.

Glass (and window), which has the highest heat loss in buildings, is becoming more prominent in recent times, and energy loss of buildings is expected to increase. However, domestic use of low-cost glass, which is superior in energy-saving effect compared with ordinary glass, is insignificant, and high-performance glass production technology of high performance is not secured. With the recent introduction of institutional devices related to energy saving, Roy Glass is expected to demand explosive demand, and it is urgent to secure domestic high-performance glass production technology to replace foreign technology.

In addition, according to the recent architectural trends, the aesthetic role of exterior facades of buildings has been emphasized, and as a building interior and exterior material, which can best express the visual aspect freely, At the same time, various colors, saturation, brightness and the like can be expressed by composition change or coating, and various appearance can be created. For this reason, the proportion of glass in exterior members is gradually increasing in modern buildings, and in the case of commercial high-rise buildings, the exterior surface is made of glass.

The low-emission glass can be classified into two types according to the manufacturing method. The soft-low-E glass by the sputtering process and the hard furnace by the Atmospheric Pressure Chemical Vapor Deposition (Hard Low-E) glass. Since the coating film is an oxide film formed at a high temperature, it can be post-strengthened and has a merit of being freely handled. On the other hand, there is a decisive disadvantage that insulation and shielding performance are lowered by soft conductive material due to low electric conductivity of the coating film There is a limit to large-scale supply.

On the other hand, since the coating layer is composed of Ag, which is the metal having the highest electrical conductivity, the soft layer has a relatively excellent adiabatic and shielding performance and is composed of a multilayer film including various auxiliary films. Therefore, It has an advantage of being able to supply products of various characteristics.

These low-emission glasses are preferred from the aesthetic point of view, in that they have a color that is almost no color than the color of the eye. Neutral-based colors are preferred, and especially low- .

However, in the case of multi-layer coated glass, since the optical properties such as the refractive index of each layer are different, the color appears due to the interference effect. Therefore, in order to realize a neutral color having no color and only darkness, There are many difficulties.

The present invention provides a low emissivity glass having a emissivity of 0.01 to 0.03 and a visible light transmittance of 40% or more and realizing a neutral color by including a dual functional reflective metal layer having a specific thickness ratio.

The glass of the present invention is a glass coated with a first dielectric layer, a first functional reflective metal layer, a second dielectric layer, a second functional reflective metal layer, and a third dielectric layer sequentially on a glass substrate, And the second functional reflective metal layer is 20 to 35 nm, and the ratio of the thickness of the first functional reflective metal layer to the total thickness of the first and second functional reflective metal layers is 55% to 65%.

In the case of using the low-emission glass of the present invention, it is possible to achieve a neutral color and a high thermal performance with an emissivity of 0.01 to 0.03 and a visible light transmittance of 40% or more.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 shows a schematic view of the low emissivity glass of the present invention.
2 shows a schematic view of a low emissivity glass made in an embodiment of the present invention.
3 is a graph showing a change in hue according to the ratio of the first functional reflective metal layer (Ag layer).

Hereinafter, the present invention will be described in more detail.

The glass of the present invention includes the first and second functional reflective metal layers as shown in Fig. 1, and the functional reflective metal layer has a specific ratio, so that it can have excellent thermal performance and optical properties.

The glass of the present invention may include other coating layers in addition to the functional absorbing metal protective layer and the dielectric layer, and is not limited to the description of the present invention.

In one embodiment, the glass of the present invention may be coated on a glass substrate with a plurality of coating layers, that is, a main dielectric layer, a sub-dielectric layer, a functional absorbing metal protective layer, a functional reflective metal layer and a top protective layer, .

As the glass substrate used in the glass of the present invention, ordinary glass such as soda lime glass used for construction or automobile can be used. Depending on the intended use, glass having a thickness of 2 to 12 mm may be used, but the present invention is not limited thereto.

In the glass of the present invention, the first, second and third dielectric layers each comprise a Si-based nitride containing at least one element selected from Zr, Sn, Nb, Al, Sb, Mo, Cr, Ti and Ni A main dielectric layer; And at least one sub-dielectric layer including a Zn-based oxide containing at least one element selected from Sn, Nb, Al, Sb, Mo, Cr, Ti and Ni, and the main dielectric layer may be thicker than the sub- have. In this specification, the main dielectric layer and the sub-dielectric layer included in the first dielectric layer are referred to as a first main dielectric layer and a first sub-dielectric layer, respectively.

The first to third main dielectric layers intercept Na ⁺ which is diffused from the lower soda lime glass during heat treatment for strengthening and bending, and blocks oxygen or ions transferred to the metal layer.

In the present invention, the first to third main dielectric layers contain at least one Si-based nitride selected from Zr, Sn, Nb, Al, Sb, Mo, Cr, Ti and Ni, .

The first dielectric layer and the third dielectric layer are located on the lower and upper portions of the glass of the present invention, and the thicknesses of the first to third dielectric layers may be 10 to 30 nm. The thickness of the second dielectric layer positioned between the first dielectric layer and the third dielectric layer may be 70 to 90 nm. If the thickness of the second dielectric material is out of the above range, it is deviated from the thickness ratio of the first and second functional reflective metal layers described above, so that it is difficult to realize the neutral color, and the color change depending on the viewing angle is severe.

The glass of the present invention includes first and second functional reflective metal layers each coated between the dielectric layers and reflecting infrared rays or solar heat rays. The material of the functional reflective metal layer may be any one selected from Ag, Au, Cu, Al, Pt, and combinations thereof, such as Ag. Ag best fits high transmittance and good durability in the visible light range. The functional reflective metal layer serves to selectively transmit or reflect the solar radiation (IR) region.

The sum of the thicknesses of the first and second functional reflective metal layers may be 20 to 35 nm and the ratio of the thickness of the first functional reflective metal layer close to the glass substrate may be 55 to 65% Lt; / RTI > When the sum of the thicknesses of the functional reflective metal layers is out of the above range, it is difficult to realize the emissivity of 0.01 to 0.03 required in the present invention. If the thickness ratio is out of the above range, it may be difficult to realize neutral color.

The glass of the present invention is a glass comprising a Ni alloy or a Ni alloy nitride which is located on each of upper and lower surfaces of the first and second functional reflective metal layers and contains at least one element selected from Cr, Ti, Cu, Nb and Zr 1 to 4 < th > functional absorbing metal protective layer. The functional absorbing metal protective layer serves as a barrier to obstruct the movement of O ₂ in the air during the heat treatment for strengthening and bending, and also helps the reflective metal layer to perform stable behavior even under high heat treatment conditions.

As shown in FIG. 2, the first and second functional absorbing metal protective layers are disposed on the top and bottom surfaces of the first functional reflective metal layer, and the third and fourth functional absorbent metal protective layers This location can be. Although not particularly limited, the thickness of each of the functional absorbing metal protective layers may be 0.5 to 5 nm. If the thickness is out of the above range, it may be difficult to realize a visible light transmittance of 40%.

The glass of the present invention is disposed on the upper surface of the first main dielectric, the upper surface and the lower surface of the second main dielectric, and the lower surface of the third main dielectric, and is selected from Sn, Nb, Al, Sb, Mo, Cr, And first to fourth sub-dielectric layers including a Zn-based oxide containing at least one element, for example, a Zn-based oxide containing Al. The sub-dielectric layer is deposited on the bottom of the reflective metal layer to induce crystallization of the reflective metal layer. In addition, when the reflective metal layer is heat-treated, it prevents the oxygen gas from diffusing into the upper and lower dielectric layers, And the like.

As shown in FIG. 2, the first sub-dielectric layer is located on the top surface of the first main dielectric layer, the second sub-dielectric layer and the third sub-dielectric layer are located on the top and bottom surfaces of the second main dielectric layer, The fourth sub-dielectric layer may be located in the second sub-dielectric layer. Although not particularly limited, the thickness of each of the sub-dielectric layers may be 5 to 20 nm. When the thickness is out of the above range, crystallization of the reflective metal layer may not be performed well.

The glass of the present invention may include an uppermost protective layer which is located on the upper surface of the third main dielectric and contains an oxide, a nitride or a nitride oxide containing at least one element selected from Ti, Zr and Si, . Where y / x <1, for example x: y can be from 100 mol% to 0 mol% to 75 mol%: 25 mol% based on 100 mol% of the sum of x and y.

The top protective layer reduces the surface roughness, increases the scratch resistance, and increases the mechanical and chemical durability of the coating film. The thickness of the overcoat layer is 2 to 15 nm, for example 2 to 9 nm. If it is less than 2 nm, the durability may be deteriorated, and if it exceeds 15 nm, the transmittance may be decreased or blur may be caused.

The glass of the present invention may have an a * and b * value of -7 to 1 at an observation angle of 0 to 55 degrees, an emissivity of 0.01 to 0.03, and a visible light transmittance of 40% or more.

The CIE L * a * b * is an index representing the amount of color based on a value measured by a spectrophotometer, and can be expressed in terms of coordinates in a color display system . L * represents the brightness of the color by the amount of light, a * represents red, plus minus green, b * represents plus and yellow, and minus represents blue.

Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. However, the scope of the present invention is not limited thereto.

[ Example 1 to 3]

A 6 mm thick transparent glass was first coated with a 15 nm thick first main dielectric layer under a nitrogen / argon atmosphere. The first sub-dielectric layer was then coated with 10 nm under an argon / oxygen atmosphere. Thereafter, the first functional absorbing metal protective layer was coated to a thickness of 1 nm, and the first functional reflective metal layer Ag was coated to a thickness of 15 nm under an argon atmosphere.

A second functional absorbing metal protective layer was coated on the first functional reflective metallic layer to a thickness of 1 nm, and then the second and the second main dielectric layers were coated to a thickness of 10 nm and 80 nm, respectively.

On the top surface of the second main dielectric layer, the third sub-dielectric layer was coated to 10 nm under an argon / oxygen atmosphere, and the third functionalized absorbing metal protective layer was coated to a thickness of 1 nm. Thereafter, the second functional reflective metal layer was coated to 9 nm and the fourth functionalized absorbent metal protective layer was coated to 1 nm. The fourth sub-dielectric layer was coated to a thickness of 10 nm, the third main dielectric layer was coated to a thickness of 15 nm, and finally the top protective layer was coated to a thickness of 7 nm under an argon nitrogen atmosphere to produce a low-emission glass of Example 1.

[Film structure: first main dielectric layer / first sub-dielectric layer / first functional absorbing metal protective layer / first functional reflective metal layer (Ag) / second functional absorbing metal protective layer / second sub dielectric layer / second main dielectric layer / Third sub-dielectric layer / third functional absorbing metal protective layer / second functional reflective metal layer (Ag) / fourth functional absorbing metal protective layer / fourth sub-dielectric layer / third main dielectric layer /

The same procedure as in Example 1 was carried out except that the total thickness of the first functional reflective metallic layer and the second functional reflective metallic layer was fixed at 31 nm and the ratio of the first and second functional reflective metallic layers was varied as shown in Table 1 Low-emission glasses of Examples 2 and 3 were prepared.

The specific constituents of each layer

1) First, second and third main dielectric layers: Si-based nitride containing Al

2) First, second, third and fourth sub-dielectric layers: Zn-based oxide containing Al

3) First, second, third and fourth functional absorbing metal protective layer: NiCr alloy

4) First and second functional reflective metal layers: Ag

5) Top protective layer: TiOxNy containing TiOx ceramic material

[ Comparative Example 1 to 5]

Except that the total thickness of the first functional reflective metallic layer and the second functional reflective metallic layer was fixed at 31 nm and the ratio of the first and second functional reflective metallic layers was changed as shown in Table 1, Emitting glass.

The glass samples of the above-prepared examples were heat-treated in the following manner. In a general tempering furnace used in the production of tempered glass, the upper and lower temperatures were maintained at a temperature of about 600 to 700 DEG C, and the glass samples were heated for about 5 minutes and quenched. The visible light transmittance and reflection hue were measured according to KS L 2514 standard, and the emissivity was measured by FT-IR. The emissivity is a value measured by Ag, which is a solar radiation reflection metal layer, and shows one of the evaluation properties that can be used to evaluate performance as a low-emission glass even after heat treatment.

The measurement results of the above items are shown in Table 1 below and a graph showing the color change according to the ratio of the first functional reflective metal layer (Ag layer) is shown in FIG.

As can be seen from Table 1, the low-emission glass of the embodiment according to the present invention is excellent in thermal performance and is suitable for use in architectural glass and the like, and exhibits a neutral glass surface color even in front and side observation.

Claims

Sequentially on a glass substrate,
A glass coated with a first dielectric layer, a first functional reflective metal layer, a second dielectric layer, a second functional reflective metal layer, and a third dielectric layer,
The sum of the thicknesses of the first and second functional reflective metal layers reflecting infrared rays or solar rays is 24 to 35 nm,
The ratio of the thickness of the first functional reflective metal layer to the total thickness of the first and second functional reflective metal layers is 55% to 65%
The first dielectric layer, the second dielectric layer, and the third dielectric layer,
A main dielectric layer comprising a Si-based nitride containing at least one element selected from Zr, Sn, Nb, Al, Sb, Mo, Cr, Ti and Ni; And
And at least one sub-dielectric layer comprising a Zn-based oxide containing at least one element selected from Sn, Nb, Al, Sb, Mo, Cr, Ti and Ni,
And a second functional reflective metallic layer disposed on each of the upper and lower surfaces of the first and second functional reflective metal layers and including at least one element selected from the group consisting of Cr, Ti, Cu, Nb, and Zr, And an absorbent metal protective layer.

The glass according to claim 1, wherein the a * and b * values of the glass surface reflection color at an observation angle of 0 ° to 55 ° are -7 to 1.

The method according to claim 1,
Wherein the main dielectric layer is thicker than the sub-dielectric layer.

The glass of claim 1, wherein the second dielectric layer is 70 to 90 nm thick.

delete

The glass according to claim 1, wherein the sub-dielectric layer is located on the upper surface of the first main dielectric layer, the upper surface and the lower surface of the second main dielectric layer, and the lower surface of the third main dielectric layer.

The method of claim 1, further comprising:
A top protective layer containing an oxide, nitride or nitride oxide containing at least one element selected from Ti, Zr and Si.

The glass according to claim 1, wherein the emissivity is 0.01 to 0.03 and the visible light transmittance is 40% or more.