JPS6071547A - Process for preparing heat ray reflecting glass plate - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a heat ray reflective glass plate, and particularly to a method for manufacturing a heat ray reflective glass plate that has excellent durability.

[Technical background of the invention]

It is well known that heat-reflecting glass plates are used for architectural purposes and the like. ``The gist is as follows.The aim is to save energy in summer cooling loads, and the visible light band (0
, 3 μm to 0.7 μm) and reflects unnecessary infrared light, and its ideal spectral characteristics are shown in FIG. In Fig. 1, m = O, m = 1 and m = 2 indicate the cases where the air mass is 0°1 and 2, respectively, and the air mass is 6000°.
shows the blackbody radiant energy spectrum at 6000. Heat ray reflective glasses that have been proposed in the past are described in detail in Ceramics J 17 (1982) P, 540, etc., and can be broadly classified into the following two types.

(1) A glass plate with a heat-reflecting film formed directly on it.

(11) On plastic film: = something that is pasted onto a glass plate after forming a heat ray reflective film.

[Problems with background technology]

(1) is a method in which a translucent metal film or oxide is formed on a glass plate using a vapor deposition method, a spray method, etc. Since it is a single layer film of a metal film or oxide, it is transparent in the visible light range. The transmittance is not high, and in fact (2 commercially available ones,
It is usually 50% to 60%. In addition, the reflectance in the infrared region is not high, and commercially available products are usually about 10%.

(11) has a high transmittance in the visible light region (approximately 70 to 80
%), and also has a high reflectance in the infrared region (approximately 50-70%)
However, because it uses a plastic film, its mechanical strength is weak and it is easily scratched, so even when it is attached to the interior of a room, there are many problems in terms of longevity.

[Purpose of the invention]

The present invention was made in view of the above-mentioned drawbacks of the prior art, and was made with the purpose of providing a heat ray reflective glass plate that is durable and has good degradation characteristics.

[Summary of the invention]

In the method for manufacturing a glass plate, a heat ray reflecting film consisting of a dielectric multilayer film mainly consisting of alternating layers of a high refractive index material and a low refractive index material is formed on both sides of the glass plate surface. The film is formed by a dipping method using a solution, and at least one type of dielectric film is formed into a predetermined film by repeating the process of [dipping-pulling-heat treatment] two or more times using a solution of a metal compound. This is a method for manufacturing a heat ray reflective glass plate characterized by forming it thickly.

[Embodiments of the invention]

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

As the glass plate, ordinary architectural glass is used. For example, the wall thickness is in order of 5. Since the area is plate glass,
It has a large area.

The case where titanium dioxide is used as the high refractive index dielectric thin film and the case where silicon dioxide is used as the low refractive index dielectric thin film will be described in detail.

For the formation of a thin film of titanium dioxide, titanium alkoxide (T I (OR)4) as solute can be used, for example, titanium isoprooxide (Tt (t-ocH, t-r,)4
A solution of ethanol and ethyl acetate containing 3.4% of (the ratio of ethanol to ethyl acetate is 9:1) is used as the solution.

Furthermore, in order to form a thin film of silicon dioxide, a silicate ester is used as a solute. As the silicate ester, for example, a solution containing 5.9% silicon ethoxide < 5i (QC, n, ) as main components of methanol and ethanol, to which methyl acetate and ethyl acetate are added is used.

The dielectric multilayer film is obtained by repeating the steps of dipping it in a solution, pulling it up from the solution, and heat-treating it. FIG. 3 shows a conceptual diagram of the dipping method.

The thickness of each layer is controlled by the rate of withdrawal from the solution.

the rate of withdrawal from solution and the temperature at which the membrane becomes clear and stable;
For example, the relationship between film thickness after heat treatment at 600°C for 20 minutes is shown in Figure 4 for titanium dioxide, and Figure 5 for silicon dioxide. In both cases, as the pulling speed increases, the film thickness increases. To increase.

The film thickness is Tay/? It was measured using Tali Step ζ2 manufactured by Or Hobson.

[Example 1] Now, the process of forming a dielectric multilayer film for heat ray reflection on both sides of the glass plate (1) is as follows. That is, in order to form the first layer of titanium dioxide, a glass plate (1
) is immersed in the first solution.

Next, as shown in FIG. 3, the glass plate is pulled up by a pulling device (not shown) at a pulling speed of, for example, 14 mm/sec. Then, a thin film of titanium dioxide is formed on both sides of the glass plate (1). Next, heat treatment is performed in the atmosphere at, for example, 600° C. for 20 minutes.

A transparent, stable and strong titanium dioxide thin film (3) is then formed. The thickness of the film formed at this time is 1080A. Next (=, the glass plate (1) on which the titanium dioxide thin film (3) has been formed is immersed in a second solution for forming a silicon dioxide film. Using the same method, the pulling speed is controlled, and for example, 15 mm /see.

Next, heat treatment is performed in the atmosphere for, for example, 600 minutes (20 minutes) to form a transparent, stable, and strong silicon dioxide thin film.The thickness of the film formed at this time is 1700A.

Thereafter, similarly, thin films of titanium dioxide and silicon dioxide are alternately formed to form a dielectric multilayer film.

The number of layers of a dielectric multilayer film having good spectral characteristics as a heat ray reflection filter is usually 6 layers on one side and 9 layers on both sides, totaling 12 layers.

The required thickness of each layer is determined from the fact that the cut-off half-value wavelength for reflecting infrared region is approximately 800 nm.

The center wavelength λ corresponds to the half-value wavelength of 800 mm. Set ・
The film thickness 6 of each layer is determined from the condition 6=5. Here n is the refractive index. Now, the refractive index of titanium dioxide is 2,3
Then, the film thickness of titanium dioxide is 1080X, and if the refractive index of silicon dioxide is 1.47, the film thickness of silicon dioxide is 1700A. From FIGS. 4 and 5, in order to form the titanium dioxide thin film (3), it is sufficient to pull it from the first solution at a pulling speed of 14 mm/sec.
It turns out that it is sufficient to pull at the same pulling speed as that of silicon dioxide. Table 1 shows the composition of the material of the layer on one side of this example, the film thickness,
The relationship between pulling speed is shown. In addition, Fig. 7 (- indicates the spectral characteristics of the corresponding hot ray refractory glass plate. Since the absorption of the dielectric multilayer film is almost negligible in the wavelength range of 0.3 μm to 2.5 μm, the reflectance is This is an inverted version of Figure 7.

Table 1 However, the number of layers increases, and in the case of Tie2 in the fifth layer,
When attempting to form 1080A by one dip-pulling, cracks often occur in the TiO2 film. It has been found that this cranking can be prevented by repeating the C-dip-pulling-heat treatment process twice, once, or multiple times until the desired film thickness is achieved. For example, to form the fifth layer TlO2 of 108OA,
It is sufficient to repeat the process of pulling at a pulling speed of 4 nods/expression and heat-treating at 600° C. for 30 minutes in the atmosphere twice. Through the above steps, it was possible to prevent cracks in the tie and film.

In Table 1, the number of layers is counted from the glass plate (1) side, and it goes without saying that the multilayer film on both sides of the glass plate (13) forms a heat ray reflective filter.

[Example 2] In the case of the above [Example 1] (2 is 0.8 μm to 1
．． Light in the 2 μm wavelength range can be well reflected, but as is clear from Figure 1, the actual radiation spectrum of sunlight also includes infrared rays beyond that range. Sarat
- Of course, it is desirable to be able to reflect even long wavelength infrared rays. In this embodiment, an example will be described in which a broadband heat ray reflective glass plate is manufactured using a dipping method. The method for forming the thin film of titanium dioxide and silicon dioxide is the same as in [Example 1]. That is, after being immersed, the material is pulled up by controlling the pulling speed, and then heat treated.

Table 2 shows the relationship among the material composition, film thickness, and pulling speed of the layer on one side of this example. Moreover, FIG. 8 shows the spectral characteristics of the heat ray reflective glass plate.

As described in [Example 1] and [Example 2], since the manufacturing method of the present invention uses the dipping method, a dielectric thin film is simultaneously applied to both sides of the glass plate (1). It is possible to form a durable heat ray reflective filter at an extremely low cost.

It should be noted that as the dielectric film is thick and the final layer of the multilayer film approaches (for example, when forming the fifth or sixth layer in Table 2), the film often cracks due to heat treatment. In such a case, instead of forming a thick film at once, the same film is formed multiple times with a thin film thickness to form a thick film. Using the corresponding metal compound solution [dip-pulling-heat treatment]
If the desired film thickness is formed by repeating the process twice or more, cranking of the film can be prevented.

Further, in the above embodiment, a heat ray reflective filter using only a high refractive index material and a low refractive index material is described in detail, but a heat ray reflective filter can also be formed using an intermediate refractive index material in a predetermined layer. Of course, this is also true. For example, instead of titanium dioxide, indium oxide (I n2 o, ), yttrium oxide (yt
os) or zirconium oxide (Zr02), etc. may be used. For example, the solute in the solution for forming a thin film of yttrium oxide is yttrium nitrate (Y(Now)s).
) may be used, and indium nitrate (Inoios) a can be used as the solute of the solution for forming a thin film of indium oxide.
) can be used.

Moreover, it is also possible to use one of the heat treatment steps of this example together with the strengthening treatment in the tempered glass plate manufacturing process.

That is, by forming a dielectric film and rapidly cooling the plate glass after heat treatment, tempered glass can be formed.

The heat treatment step that also serves as a strengthening treatment can be performed on any layer during the heat treatment during the formation of the multilayer film, but it is particularly effective if it is performed during the heat treatment step during the formation of the final layer.

〔Effect of the invention〕

As described above, the present invention has a dielectric multilayer film on both sides, and can provide a durable, high-performance heat ray reflection area at a low cost.

[Brief explanation of drawings]

The Zheng 1 diagram is a diagram showing the radiation spectrum from sunlight, the 2nd diagram
The figure shows the spectral characteristics of an ideal heat-reflecting glass plate, Fig. 3 is a conceptual diagram of the dipping method, Fig. 4 is a cross-sectional diagram of a heat-reflecting glass plate, Fig. 7, and Fig. 8 (1)...Glass. plate, (2)... dipping solution, (3)... thin film of high refractive index substance, (4)... thin film of low refractive index substance. Agent: Patent Attorney Noriyuki Chika (and 1 other person) No. 1
Figure wavelength Ot species) Figure 2 His clothes (Monk A) Figure 3 Figure 4 Figure 5 Figure 1 and tg fn da sec

Claims (3)

[Claims] (1) In a method for manufacturing a heat ray reflective glass plate having a dielectric multilayer film mainly consisting of alternating layers of high refractive index material and low refractive index material on both sides of the glass plate surface, the dielectric multilayer film is configured. Production of a heat ray reflective glass plate characterized in that at least one type of dielectric film is formed to a predetermined film thickness by repeating the process of [Dinbu pulling-heat treatment] two or more times using a solution of a metal compound. Method. (2) The method for manufacturing the low plate, wherein the high refractive index substance is titanium dioxide. (3) The method for manufacturing a heat ray reflective glass plate according to claim 1, wherein the heat treatment also serves as a strengthening treatment for the glass plate.