JPH02225345A - Highly transmissive heat-reflective glass - Google Patents

Abstract

PURPOSE:To obtain the title glass imparted with both high transmittance and reflectance and improved in weatherability by laminating a glass plate with, as the first to fourth layers, respective specific materials at respective specified film thicknesses and by coating, as the outermost layer, another specific material at specified thickness. CONSTITUTION:A glass plate 1 is coated with (A) TiO2 layers consisting of high refractive index material and (B) SiO2 layers consisting of low refractive index material, in the following manner: (1) the first layer: TiO2 layer 16-20nm thick. (2) the second layer: SiO2 168-212nm thick, (3) the third layer: TiO2 layer 79-99nm thick, and (4) the fourth layer: SiO2 layer 29-37nm thick. Furthermore, the resultant laminate is coated with, as the outermost layer, a SnO2 layer 17-21nm thick. As the above-mentioned layers is thin as a whole, time required for the coating operation will be short, enabling the productivity in the coating processes to be improved.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to heat-reflecting glass for automobiles or architecture that has a high visible light transmittance and effectively reflects solar radiant energy. The present invention relates to a heat-reflecting glass having the above visible light transmittance.

[Conventional technology]

Conventionally, heat ray reflective glass made by laminating thin films of high refractive index material and low refractive index material alternately on a glass plate has a structure of a heat ray reflective film (as seen in JP-A-58-202408, for example). board) L/2 HL HL/2 (H:I
A layer of high refractive index material with an optical thickness of /4λ, L: 1/4λ
A layer of a low refractive index material with an optical Jld thickness (λ is the design wavelength) and a structure of (substrate) HT-HL/2 are known. In either case, the structure of these heat ray reflective films is based on an alternating laminate of high refractive index layers and low refractive index layers with an optical thickness of 1/4λ, and this laminate allows The outermost layer, which is made of a low refractive index material p+ and has an optical thickness of ]/8λ, has a heat ray reflecting effect and serves as an antireflection layer against visible light.

[Problem to be solved by the invention]

Therefore, conventional heat-reflective glass has a structure in which a layer with a thickness of 1/8λ as a visible light reflection prevention layer is laminated on a laminate of layers with a thickness of 1/4λ as a heat-ray reflection layer. Therefore, the total nx thickness is thick (and when coating by sputtering method on a substrate that requires a large area such as for automobiles or architecture, it takes a long time), resulting in heat ray reflection. There was a problem in that the cost of stopping production of glass was high.

The present invention has a visible light transmittance of 70% or more, a solar transmittance of 60% or less, and a visible light reflectance of 10% or less, and furthermore, the reflected color and transmitted color are different from the reflected color and transmitted color of the glass itself. The object of the present invention is to provide a heat-ray-reflecting glass that does not change significantly, and requires less time for coating with a heat-ray-reflecting film having the above-mentioned characteristics.

[Means to solve the problem]

The heat ray reflective glass according to the present invention has a TiCh layer which is a layer of a high refractive index material and a SiO□ layer which is a layer of a low refractive index material on a glass plate. The layer is a Tioz layer, the second layer and the fourth layer are SiO□ layers, and the Tj
At least one of the O□ layer and the SiO□ layer has a 1/2
It is coated thinner than the optical film thickness of 4λ, and the outermost layer is S.
An nO2 layer is provided, and the first layer of Ti(l
Z film thickness is 1.6 to 20 layers m, second N 5iO1 film j
7 has a thickness of 168 to 21.2 m, the thickness of the third layer TiO2 is 79 to 99 m, and the thickness of the fourth layer 5i02 is 29 to 37 m.
layer m, and the thickness of the outermost SnO□ layer is 17~
21.nm heat ray reflective glass.

The second aspect of the heat-reflecting glass according to the present invention is a 1N tie counted from the glass plate side on the glass plate.

The film J7 is 95 to 121 layers m, the thickness of the second N-SiO2 is 168 to 214 m, the third layer Tie2 is 34 to 42 m, and the fourth layer 5i02 is 32 m. ~40
Ni, and the outermost layer is SnO, and the film thickness of the layer is 28 to 3
It is a heat ray reflective glass provided with 5 layers, 4 layers m.

A third aspect of the heat-reflecting glass according to the present invention is that the first layer of TiO2 has a thickness of 88 to 110 m, and the second layer of SiO2 has a thickness of 149 to 110 m, counting from the glass plate side.
189 layers m, the thickness of the third layer TiO2 is 87 to 1109 m
This is a heat ray reflective glass provided with five layers, the fourth layer of SiO2 having a thickness of 28 to 34 m, and the outermost layer of SnO□ having a thickness of 27 to 33 m.

In any of the inventions of the heat ray reflective glass according to the present invention, if the thickness of each of the first to fifth layers exceeds the upper limit or falls below the lower limit, the visible light transmittance is less than 70%. This is not preferable because it cannot be used due to restrictions imposed by the JIS standards for automobile window glass. The range of film thickness for each layer described above corresponds to approximately ±12% from the center value of the film thickness, and the film thickness of each layer is less than the visible light transmittance calculated using the total 1γ formula of optical interference theory. The effect of the relative deviation from the center value was determined from FIG. 3, in which a 4 mm'yi- colored glass (manufactured by Nippon Sheet Glass Co., Ltd., trade name: Bronze Vane) was investigated. In Figure 3, mark ○, mark, 0
The marks indicate the first and second heat ray reflective glasses according to the present invention, respectively.
Among the heat ray reflective glasses of the second and third inventions, each layer is determined based on the center value of the above-mentioned film thickness range, and if the thickness deviation is within 12%, the film thickness will exceed 70%. % or more visible light transmittance can be obtained.

Further, the outermost layer of the heat ray reflective glass according to the present invention is a layer of SnO□ in order to ensure acid resistance and alkali resistance.

In carrying out the present invention, a sputtering apparatus having a magnetron cathode can be used, and TiO□
When coating a glass plate with a film, a 5iOz film, or a SnO2 film, either direct current sputtering or high-frequency sputtering can be used depending on the target material used.

[For production]

Ti in the first to fourth layers of the heat ray reflective glass according to the present invention
The alternating layers of O2 and SiO2 provide the heat-reflecting glass with the characteristics of high i3 pass rate in the visible range and high reflectance in the near-infrared range due to optical interference. Furthermore, the outermost Sn02 layer protects the TiO2 and SiO□ laminate and improves weather resistance.

〔Example〕

FIG. 1 is a schematic cross-sectional view showing the film structure of the heat ray reflective glass of the present invention, in which 1 is a glass plate, 2 is a TiO2 layer,
3 is a SiO□ layer, and 4 is an S-0□ layer.

The present invention will be explained below based on examples.

Example 1 FIG. 4 shows an in-line sputtering apparatus used to carry out the present invention, and the coating chamber has three independent planar magnetron cathodes.

Coating the glass plate with a film is done while the glass plate is passing over the cup where sputtering is being performed, and the amount of power input to the cathode or the speed of the glass plate passing over the cathode can be varied. The thickness of the resulting film was adjusted.

9 in Figure 4 is a vacuum chamber (exhaust pump is not shown)
, 10.11 are a preparation room and a take-out room, respectively, and 12.
13 and 14 respectively. They are the second and third coating chambers, and each chamber can be isolated and connected as necessary for moving the glass plate by opening and closing a gate valve 15.1.6.17.18. The glass plate 19 is moved by a conveyor belt 20. 1st 2nd. In the third coating chamber, cathodes 21, 22, 23 are installed, electrically insulated from the vacuum chamber by an insulator 24, and gas vibrators 25, 26, 27 and valves 28, 29, 29, 27, 26, 27, 27, 27, 27, 27, 27, 27, 27, 27, 27, 28, 29, 28, 29, 27, etc. are each installed in the third coating chamber, and cathodes 21, 22, 23 are electrically isolated from the vacuum chamber by an insulator 24. 30 and a power source 31, 32.3 for applying power to the cathode.
3 and switches 34, 35, 36 are installed. 1st
As targets, titanium metal 37 was attached to the cathode 21, quartz glass 38 was attached to the 20th cathode 22, and tin metal 39 was attached to the third cathode 23.

First, oxygen gas is introduced into the gas pipe 25 into the first coating chamber 12, which is attached to the metal titanium 37 as a target.
3, and the orifice valve of the exhaust pump
The pressure was adjusted to mTorr, a sputtering current of 6 A was applied to the cathode 21, and a 4 mm thick glass plate (manufactured by Nippon Sheet Glass Co., Ltd., trade name: Bronze Vane) 19 was heated at 140 Tsuru/m.
While moving over the metal titanium target at a speed of
The membrane was coated. Next, 80% by volume of argon gas and 20% by volume of oxygen gas were introduced into the second coating chamber 13, which was attached with the quartz glass 38 as a target, and the pressure was adjusted to 3mTorr using the same method. Power is applied from the high frequency power source 32, and the glass plate 19 is heated at 26 am/m.
While moving over the SiO□ target at a speed of in,
As the 2nd month of the month, he overturned the s;oJ mo of 190ntt+. Next, under the same sputtering conditions as the first layer TiO□ film, while moving the glass plate 19 over the metal titanium target in the first coating chamber at a speed of 15 mm/min,
A TiO2 film of 89 nm was coated as a third layer film.

Next, under the same sputtering conditions as the second JlSiO□ film,
While moving the glass plate 19 over the 5i02 target in the second coating chamber at a speed of 152 am/1 Ilin, a 33 nm SiO□ film was coated as the fourth layer film. Finally, 20% by volume of argon gas and 80% by volume of oxygen gas were introduced into the third coating chamber 14, which was attached with metal tin 39 as a target, the pressure inside the coating chamber was adjusted to 3 mTorr, and 4A sputtering was performed. applying a current to the cathode 23;
While moving the glass plate 19 over the metal tin target 39 at a speed of 1000/n+in, 19
A SnO□ film of nm thickness was coated. The optical properties of the obtained heat ray reflective glass and the spectral reflection properties of the film surface side were measured.
Curve 5 in Table 1 and Figure 2 was obtained. The time required for coating the membrane was 150 minutes.

Example 2 Using the same equipment as in Example 1, the film thickness of the first and third layers of TiO□ was increased by 1 by changing the moving speed of the glass plate.
．． 08im, 38im, 2nd and 4th layer 5i
(The film thickness of lz is 1.91im, 36im,
A second heat-reflecting glass was obtained in the same manner as in Example 1, except that the thickness of the fifth layer of SnO□ was 31 nm. The optical properties of this glass and the spectral reflection properties on the film surface side were measured, and curve 6 in Table 1 and FIG. 2 was obtained.

The time required for coating was 188 minutes.

Example 3 Using the same equipment as in Example 1, the film thickness of the first and third layers of TiO□ was changed to 99% by changing the moving speed of the glass plate.
im, 98im, the film thickness of the second N and fourth layer Sin□ are respectively 169im and 31im, and the thickness of the fifth layer 5
A third heat-reflecting glass was obtained in the same manner as in Example 1, except that the nOz film thickness was 30 nm. The optical properties of this glass and the spectral reflection properties of the film surface side were measured, and the first
Curve 7 in the table and FIG. 2 was obtained.

The time required for coating was 218 minutes.

Conventional Example A conventional heat-reflecting glass disclosed in Japanese Unexamined Patent Publication No. 58-202408 was manufactured.

Using the same equipment as in Example 1, the film thickness of the first and third Tie2 layers was 105r+m by changing the moving speed of the glass plate.
and the thickness of the second layer and the fourth layer are respectively l 71i
A heat ray reflective glass for comparison was obtained in the same manner as in Example 1, except that the thickness was 86 im and the fifth layer was not provided. The optical properties of this glass and the spectral refraction properties on the film surface side were measured to obtain Curve 8 (dotted line) in Table 1 and Figure 2. The time required for coating was 250 minutes.

〔Effect of the invention〕

Since the heat ray reflective glass of the present invention has a thin total film thickness, the time required for coating is short. Therefore, it is expected that productivity will improve when coating with a heat ray reflective film. Moreover, since the optical performance has the performance required for heat ray reflecting glass for automobiles, it can be used as a window glass having heat ray reflecting performance for automobiles as well as for architecture.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view showing the film structure of the heat-ray reflective glass of the present invention, FIG. 2 is a diagram showing the spectral reflection characteristics of the heat-ray reflective glass of Examples and Comparative Examples of the present invention, and FIG. 3 is a diagram showing visible light NfA.
A diagram showing the relationship between the minimum value of transmittance and the relative deviation from the center value of the film thickness of each layer, and FIG. 4 is a schematic cross-sectional view of the apparatus used to manufacture the heat ray reflective glass of the present invention. . 1...Glass plate, 2...Tie, layer, 3...5i
02 layer, 4...5nOz layer, 9... vacuum chamber, 12.
13. 1.4-...Covering chamber, 19...Glass plate,
20...Transport belt, 21.22°23...Cathode, 37.38.39...Target. Diagram wavelength (nm)

Claims (3)

[Claims] (1) In a heat-reflecting glass in which thin films of a high refractive index material and a low refractive index material that transmit visible light are alternately laminated and coated on a glass plate, the high refractive index material is TiO_2,
The low refractive index material is SiO_2, and the thickness of the first layer of TiO_2 is 16 to 20 nm counting from the glass plate side.
, the thickness of the second layer of SiO_2 is 168 to 212 nm, the thickness of the third layer of TiO_2 is 79 to 99 nm, and the thickness of the fourth layer of S
Heat ray reflective glass with a film thickness of iO_2 of 29 to 37 nm and coated with a 17 to 21 nm SnO_2 layer as the outermost layer. (2) A heat ray reflective glass in which a glass plate is coated with thin films of a high refractive index material and a low refractive index material that transmit visible light, which are alternately laminated and coated, in which the high refractive index material is TiO_2,
The low refractive index material is SiO_2, and the thickness of the first layer of TiO_2 is 95 to 121 nm, counting from the glass plate side.
m, the thickness of the second layer SiO_2 is 168 to 214 nm,
Heat-reflective glass coated with a third layer of TiO_2 having a thickness of 34 to 42 nm, a fourth layer of SiO_2 having a thickness of 32 to 40 nm, and an outermost layer of SnO_2 of 28 to 34 nm. (3) A heat ray reflective glass in which a glass plate is coated with thin films of a high refractive index material and a low refractive index material that transmit visible light, which are alternately laminated and coated, in which the high refractive index material is TiO_2,
The low refractive index material is SiO_2, and the thickness of the first layer of TiO_2 is 88 to 110 nm, counting from the glass plate side.
m, the thickness of the second layer SiO_2 is 149 to 189 nm,
A heat ray reflective glass coated with a third layer of TiO_2 having a thickness of 87 to 109 nm, a fourth layer of SiO_2 having a thickness of 28 to 34 nm, and an outermost layer of SnO_2 of 27 to 33 nm.