JPH01138159A - Heat ray shielding plate having high visible ray transmittance - Google Patents

Abstract

PURPOSE:To form a heat ray shielding plate, having visible ray transmittance and heat ray shielding ability equal to those of conventional products and durability and hardly corroding in the air, by using only a dielectric film as a heat ray reflecting film in place of a film containing silver and combining the film with a plate substrate having high visible ray transmittance and heat ray absorptivity. CONSTITUTION:A heat ray shielding plate, having a high visible ray transmittance and obtained by forming a dielectric film 2 having lambda0/4 optical film thickness (lambda0 is 0.8-1.1mum) and a refractive index as high as 1.9-2.5 on at least one surface of a plate substrate 1 (e.g., commercially available blue float glass) having 1.4-1.7 refractive index, >=75% visible ray transmittance and <=67% sunray transmittance. For example, TiO2, Ta2O5, ZrO2, SnO2, ZnO, etc., can be used as the above-mentioned dielectric film 2 having the high refractive index.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a heat ray shielding plate having high visible light transmittance and used for windows of buildings and automobiles.

[Prior Art] Conventionally, there have been products of this type as shown in FIGS. 9 and 10. The one shown in Figure 9 is a heat ray reflective film (10
3), the clear float glass plate (101) and the clear float glass plate (102) are coated with an intermediate resin film (
104) is a laminated glass (105) bonded together. In addition, the one shown in Fig. 10 is a clear float glass plate (101) with a heat ray reflective film (103) attached and a clear float glass plate (102) separated by a separator (10B) through a space (107). Bonded double glazing (10
8). The clear float glass plate (101) with the heat ray reflective film (103) attached to these laminated glass (105) and double-glazed glass (108) is placed on the float glass plate (101) as shown in Figure 11. Sequential film thickness 30
0-400A ZnO film (109), film thickness 70-150
A+71Agffl (110), film thickness 30o~40
Three layers of ZnO films (111) of 0'A are laminated. In order to prevent the Ag film (110) from being oxidized when forming the ZnO film (111) farther from the substrate (101),
10~2O between the g film (110) and the ZnO film (111)
A Zn film A is normally formed, but this Zn film is later oxidized to become a ZnO film and forms a pair with the ZnO (111), resulting in the film structure shown in FIG. 11.

These conventional products mainly utilize the excellent optical properties of the Ag film (110), that is, high visible light transmittance and low solar transmittance, and use the Z
The nO films (109) and (111) further improve visible light transmittance by acting as an antireflection layer between the Ag film (110) and the glass plate, air, or interlayer film, and at the same time, this ZnO film ( 109) and (111) are Ag films (11
0) was prevented to some extent from corrosion. Furthermore, Ag film (110
) will corrode in a few days to several months in humid outside air despite the ZnO films (109) and (1-11), as shown in Figures 9 and 10. Laminated glass (
105) and double-glazed glass (108), and the Ag film (108) is protected from exposure to humid air even after several years.
10) was devised to prevent corrosion. FIG. 12 shows the spectral transmittance of the product thus produced. In the figure (112) is the product characteristic of laminated glass (105) (1
13) are the characteristics of the product shown in FIG. Table 1 also shows the visible light transmittance and solar transmittance of these two conventional examples.

As can be seen from these data, the conventional one using an Ag film is a heat ray shielding plate having an extremely high visible light transmittance.

[Problems to be Solved by the Invention] However, if this heat ray reflective film (103) is directly exposed to humid outside air, the Ag film (110) will corrode within a few days to several months, causing This results in optical characteristics as shown in the spectral transmittance curve (114) in Fig. 12.

Such a change in optical properties causes a decrease in visible light transmittance and an increase in solar transmittance, and also has the disadvantage that corroded areas appear mottled in appearance. For this reason, products containing the conventional Ag film (110) cannot be used in applications where a glass plate is used on the deck of a car and the film formed on its surface is directly exposed to the outside air.

[Means for Solving the Problems] The present invention has been made to eliminate the drawbacks of the conventional products as described above. Using the following plate-like base material,
By using only a dielectric film instead of a silver-containing heat ray reflective film, and by supplementing the heat ray shielding ability by using a plate-shaped base material with high visible light transmittance and heat ray absorption ability, The purpose of the present invention is to provide a heat ray shielding plate that has visible light transmittance and heat ray shielding ability equivalent to that of the conventional heat ray shielding plate, and is durable enough to be used even in environments where the film is exposed to the outside air. That is, the first aspect of the present invention has a refractive index of 1.
4 to 1.7, and the visible light transmittance (JIS R310
6-1985) is 75% or more, and the solar transmittance (according to JIS R310S-1985) is 67% or less, and the optical film thickness is λ0/4 (however, λO= 0.8-1.1μm1 or more (same)
This is a heat ray shielding plate having a high visible light transmittance formed with a high refractive index dielectric film having a refractive index of 1.9 to 2.5.

Further, the second invention of the present invention provides at least one of the plate-like substrates having a refractive index of 1.4 to 1.7, a visible light transmittance of 75% or more, and a solar transmittance of 67% or less. A refractive index dielectric film with an optical thickness of λO/4 and a refractive index of 1°9 to 2.5 is placed on the surface of the high refractive index dielectric film, and an optical film with an optical thickness of λO
/8, and is a heat ray shielding plate with high visible light transmittance formed with a low refractive index dielectric film with a refractive index of 1.35 to 1.50.

In the first invention, in one of the high refractive index dielectric films,
A low refractive index dielectric film having an optical thickness of λ0/4 and a refractive index of 1.35 to 1.50 is formed on the low refractive index dielectric film, and an optical film having an optical thickness of λ0/4 and a refractive index of 1.35 to 1.50 is formed on the low refractive index dielectric film. It is possible to form a second high refractive index dielectric film having a value of 1.9 to 2.5.

Furthermore, the optical film thickness on the second high refractive index dielectric film is λ.
A low refractive index dielectric film with a refractive index of 1.35 to 1.50 is formed at O/4, and an optical film thickness of λ0 is formed on the low refractive index dielectric film.
/4, a third high refractive index dielectric film having a refractive index of 1.9 to 2.5 can be formed.

On the other hand, in the second invention, between the high refractive index dielectric film and the low refractive index dielectric film having an optical thickness of λ0/8, an optical film having an optical thickness of λ0/4 and a refractive index of 1° is provided. A dielectric film with a low refractive index of 35 to 1.50, an optical film thickness of λO/4, and a refractive index of 1.
9 to 2.5 of the second high refractive index dielectric film can be sequentially formed.

Further, the optical film thickness is λO on the second high refractive index dielectric film.
The optical film thickness is λ0 between the low refractive index dielectric film of /8
/4 and a second low refractive index dielectric film with a refractive index of 1.35 to 1°50 and an optical film thickness of λ0/4 and a refractive index of 1.9 to 2.
．． It is also possible to sequentially form the third high refractive index dielectric film No. 5.

In the present invention, the high refractive index dielectric film is TiO2, T
a205, Z r02 + 5n02, Zl
lo.

ITO (In203+5n02), Pr601[+Ti
Either O2 or ZrO2+TiO2 can be used, and the low refractive index dielectric film can be made of MgF2.5i02.

[Function] Since the present invention has the above-described configuration, the solar transmittance can be suppressed to a certain degree while maintaining high visible light transmittance by the plate-like base material, and furthermore, due to the light interference effect of each dielectric film, , center wavelength λ0: The transmittance decreases in the wavelength range centered on 1°0 μm, so the solar transmittance decreases, and the transmittance does not decrease near the wavelength 0.5 μm, which is half the center wavelength λ0, so visible light is transmitted. The rate will continue to be maintained. Also,
The plate-like base material and dielectric film used in the present invention do not corrode easily in the atmosphere, unlike conventionally used silver thin films, and have excellent wear resistance.

[Example] Hereinafter, embodiments of the present invention shown in the drawings will be described in detail.

Example 1 In FIG. 1, (1) is a substrate, which is commercially available blue float glass (thickness 4u).

(2) is a TiO2 film having an optical thickness of λ0/4 with a center wavelength λo=i and 0 μm, and its refractive index is 2.4 in the visible light range. This film was created by direct current sputtering. Obtained heat ray 31! The visible light transmittance and solar transmittance of the i-shield plate are shown in Table 1, and its spectral reflectance is shown in Figure 5, and it itself has a high visible light transmittance and a certain degree of heat ray shielding performance. are doing. Table 1 also shows the visible light transmittance of conventional example 1 and the conventional example shown in FIGS. 9 and 10 (as shown in FIG. 9 and FIG. Example 2 In FIG. 2, (21) is the same blue float glass (thickness 4m+w) F plate as in the first example.

(22) and (24) are center wavelengths.

The T02 film has an optical thickness of λ0/4 with a=t and O μm, and its refractive index is 2.4 in the visible light range.

(23) is a 5i02 film with an optical thickness of λ0/ with a center wavelength λO = 1.0/1 m, and its refractive index is 1.46 in the optical range.
It is. All of these films were created by flow sputtering. Since the dielectric heat ray reflective layer consists of three layers, the spectral transmittance in Figure 6 and the
The solar transmittance is further reduced compared to the actual example. The durability of the muff is the same as in the first example.

Since it is formed of only a dielectric film, there is no problem at all.

2 Example 3 In FIG. 3, (31) is a blue float glass substrate (thickness: 4 mm). (32
) is the center 〒. A TiO2 film with an optical thickness of λO/4 at a wavelength λO = 1.0 μm, and its refractive index is 2 in the visible light range.
．． There are 4. (33) is the center wavelength λO=1.
5i02 with 0μm λ harm and 0/8 optical thickness
The film has a refractive index λ of 1.46 in the visible light range.

i 1st
Table 1 These films were all produced by direct current sputtering. In this way, compared to the first embodiment, by adding the 5i02 film (33) with an optical thickness of λ0/8 as the outermost layer,
This layer acted as an anti-reflection layer between the remaining parts (32) and (31) and the air, resulting in a significant increase in visible light transmission.

The spectral transmittance obtained in this example is shown in FIG. 7, and the visible light transmittance and solar transmittance are shown in Table 1. Also, the heat ray shielding plate of this example has excellent durability (no problems) as in the other examples.

Example 4 In FIG. 4, (1) is a blue float glass substrate (thickness: 4 cm). (42) and (44) are Ti having an optical thickness of λ0/4 with a center wavelength λO=1.0μ+1.
The O2 film has a refractive index of 2.4 in the visible light range. (43
) is a 5i02 film having an optical thickness of λO/4 with a center wavelength λ0: 1°0 μm, and its refractive index is 1.46 in the visible light range. (45) is a 5i02 film with an optical thickness of λ0/8 with a center wavelength λ0 = 1.0 μm, and its refractive index is 1 in the visible light range.
It is ゜46. All of these films were created by direct current sputtering. In this way, compared to the second embodiment, by adding the 5i02 film (45) with an optical thickness of λ0/8 as the outermost layer, this layer forms the remaining parts (44), (43).
(42) It acted as an antireflection layer between (41) and air, and as a result, the visible light transmittance was significantly improved. In addition, compared to the third embodiment, the number of heat ray reflective layers is two more layers, making it a total of four layers, so the solar transmittance is further increased as shown in the spectral transmittance in Figure 8 and Table 1. reduced. As for durability, there is no problem at all as in the other examples. Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments. For example, in each example, the visible light transmittance is 79.1% and the solar transmittance is 68.6%.
However, in the present invention, even better heat ray shielding performance can be achieved by using glass containing even more iron.

Further, in Examples 1 to 4, T was used as the high refractive index dielectric film.
i 02 was used, but T a205 (refractive index 2
．． 15), ZrO2 (refractive index 2.05), S r102
(refraction $2.0), ZnO (refractive index 2°0), I
TO (I n203 +5n02 , refractive index 2°0) can also be used by forming a film by the direct current spackle method. The above-mentioned high refractive index dielectric film and Pr6O1
1+TiO2 (refractive index 2.1), ZrO2+TiO2 (
A film having a refractive index of 2.1) can be formed by a vacuum evaporation method. In Examples 1 to 4, 5i02 was used as the low refractive index dielectric film, but MgF2 may also be used in addition to 5i02 when forming the film by vacuum evaporation. Furthermore, among the above, TiO2,5n02 can be easily formed by a known thermal decomposition method, and TiO2 *rTo
, Si○2 can be easily formed by a known liquid phase growth method and can be used in the present invention.

In particular, when ITO, 5n02 is used, it has the advantage of being able to block light with a wavelength longer than 2 μm.

[Effects] As described above, according to the present invention, only a dielectric film is used as the heat ray reflecting film instead of one containing silver, and the plate-like base material has high visible light transmittance and heat ray absorption ability. By increasing the heat ray shielding ability using silver, it has the same visible light transmittance and heat ray shielding ability as conventional heat ray shielding plates using silver, and is durable enough to be used even in environments where the film is exposed to the outside air. It is possible to obtain a heat ray shielding plate with properties.

Since the film can be used while exposed to humid air, it can also be used in places where a single glass plate is used, such as in the side windows of automobiles. In addition, when high visible light transmittance and heat shielding ability are required as window materials for buildings, car side windows can be used without using conventional expensive window materials such as laminated glass or double glazing. Similarly, the heat ray shielding plate of the present invention can be used as a single plate.

[Brief explanation of the drawing]

1 to 8 show embodiments of the present invention, and FIGS. 9 to 12 show conventional examples, in which FIG. 1 is a sectional view of a heat ray shielding plate, and FIGS. 5 to 8 are spectral transmittance curves of each aspect of the heat ray shielding plate. FIGS. 9 and 10 are sectional views of a conventional heat ray shielding plate. FIG. 11 is an enlarged sectional view of the glass plate and the heat ray reflective film. 11 1 2L 311 41; Blue float glass 2.22.24, 32.42, 44; High refractive index dielectric film 3.33, 43, 45; Low refractive index dielectric film 101.10
2.107; Clear float glass 103; Heat ray reflective film, 104: Intermediate resin film Fig. 1
Figure 2 Figure 3 Figure 4 Procedural Amendment Document Patent Application No. 1986 (Sho. 6) Cor. Applicant address 4-8 Doshomachi, Higashi-ku, Osaka-shi, Osaka Name (
goo) Representative Nobu Saga of Nippon Sheet Glass Co., Ltd. Agent 7, Contents of the amendment (1) The statement of the scope of claims from page 1, line 5 of the specification to page 3, line 8 of the specification The entire text has been corrected as shown in the attached sheet. Amended Claims (1) At least one of the plate-like base materials having a refractive index of 1.4 to 1.7, a visible light transmittance of 75% or more, and a solar transmittance of 67% or less On the surface, the optical film thickness is λo/4 (
A heat ray shielding plate having a high visible light transmittance formed with a high refractive index dielectric film having a refractive index of 1.9 to 2.5. (2) On the high refractive index dielectric film, the optical film thickness is λ0/
4, a low refractive index dielectric film with a refractive index of 35 to 1.50 is formed, and an optical film thickness of λ0/4 is formed on the low refractive index dielectric film.
A heat ray shielding plate having high visible light transmittance according to claim 1, wherein a second high refractive index dielectric film having a refractive index of 1.9 to 2.5 is formed. (3) The optical film thickness is λ0 on the second high refractive index dielectric film.
/4, a low refractive index dielectric film with a refractive index of 1.35 to 1.50 is formed, and an optical film thickness of λ0/4 is formed on the low refractive index dielectric film.
4. A heat ray shielding plate having high visible light transmittance according to claim 2, wherein a third high refractive index dielectric film having a refractive index of 1.9 to 2.5 is formed. (4) An optical film thickness is applied to at least one surface of a plate-shaped substrate having a refractive index of 1.4 to 1.7, a visible light transmittance of 75% or more, and a solar transmittance of 67% or less. is λ0/4,
A high refractive index dielectric film with a refractive index of 1.9 to 2.5, an optical film thickness of λO/8 on the high refractive index dielectric film, and a refractive index of 1.9 to 2.5.
A heat ray shielding plate with high visible light transmittance formed with a dielectric film with a low refractive index of 35 to 1.50. (5) between the high refractive index dielectric film and the low refractive index dielectric film having an optical thickness of λ0/8, an optical film having an optical thickness of λ0/4;
A low refractive index dielectric film with a refractive index of 1.35 to 1.50 and a second high refractive index dielectric film with an optical thickness of λ0/4 and a refractive index of 1°9 to 2.5 are sequentially formed. A heat ray shielding plate having high visible light transmittance according to claim 4. (6) The optical film thickness on the second high refractive index dielectric film is λ0
The optical film thickness is λ0/8 between the low refractive index dielectric film and the low refractive index dielectric film.
4, a second refractive index dielectric film with a refractive index of 1.35 to 1.50, an optical film thickness of λ0/4, and a refractive index of 1.9 to 2.5.
A heat ray shielding plate having a high visible light transmittance according to claim 5, wherein a third high refractive index dielectric film is sequentially formed.

Claims (6)

[Claims] (1) An optical film thickness is applied to at least one surface of a plate-shaped substrate having a refractive index of 1.4 to 1.7, a visible light transmittance of 75% or more, and a solar transmittance of 67% or less. Heat ray shielding with high visible light transmittance formed with a high refractive index dielectric film with a refractive index of 1.9 to 2.5 and a refractive index of 1.9 to 2.5. Board. (2) Optical film light is applied to the high refractive index dielectric film at λ0/
4, a low refractive index dielectric film having a refractive index of 1.35 to 1.50 is formed, and an optical film thickness of λ0/4 is formed on the low refractive index dielectric film.
A heat ray shielding plate having high visible light transmittance according to claim 1, wherein a second high refractive index dielectric film having a refractive index of 1.9 to 2.5 is formed. (3) The optical film thickness is λ0 on the second high refractive index dielectric film.
/4, a low refractive index dielectric film with a refractive index of 1.35 to 1.50 is formed, and an optical film thickness of λ0/4 is formed on the low refractive index dielectric film.
4. A heat ray shielding plate having high visible light transmittance according to claim 2, wherein a third high refractive index dielectric film having a refractive index of 1.9 to 2.5 is formed. (4) An optical film thickness is applied to at least one surface of a plate-shaped substrate having a refractive index of 1.4 to 1.7, a visible light transmittance of 75% or more, and a solar transmittance of 67% or less. is λ0/4,
A high refractive index dielectric film with a refractive index of 1.9 to 2.5, and an optical film on the high refractive index dielectric film with an optical thickness of λ0/8 and a refractive index of 1.9 to 2.5.
A heat ray shielding plate with high visible light transmittance formed with a dielectric film with a low refractive index of 35 to 1.50. (5) between the high refractive index dielectric film and the low refractive index dielectric film having an optical thickness of λ0/8, an optical film having an optical thickness of λ0/4;
A low refractive index dielectric film with a refractive index of 1.35 to 1.50 and a second high refractive index dielectric film with an optical thickness of λ0/4 and a refractive index of 1.9 to 2.5 are sequentially formed. A heat ray shielding plate having high visible light transmittance according to claim 4. (6) The optical film thickness on the second high refractive index dielectric film is λ0
The optical film thickness is λ0/8 between the low refractive index dielectric film and the low refractive index dielectric film.
4, a second low refractive index dielectric film with a refractive index of 1.35 to 1.50, an optical film thickness of λ0/4, and a refractive index of 1.9 to 2.
5. The heat ray shielding plate having high visible light transmittance according to claim 5, wherein the third high refractive index dielectric film of No. 5 is sequentially formed.