JPH03187734A - Heat rays barrier glass - Google Patents

Abstract

PURPOSE:To obtain a heat rays barrier glass with neutral transparency and reflected color by laminating a heat rays absorbing film and an oxide film on a transparent substrate and providing an oxide film with a specified refractive index at its outermost layer of the air side. CONSTITUTION:A heat rays barrier glass is prepd. by laminating successively at least two layers consisting of a heat rays absorbing film 2 and an oxide film 3 on a transparent substrate 1 and wherein the oxide film 3 is the outermost layer of the air side and has a refractive index of 2.0 or smaller. If the refractive index of the oxide film exceeds, reflectance of visible light ray becomes large and as the result, transmittance of visible light ray becomes low and the transmittance of visible light ray of 70 % or higher is hardly obtd. The oxide film 3 lowers the reflectance of the heat rays barrier glass because of the refractive index and the thickness and contributes to the improvement of the transmittance of the visible light ray and lowers the stimulating purity of the reflective color and has an action for neutralizing the whole color tone. Furthermore, wear resistance and chem. resistance of the heat rays barrier glass are improved. A heat rays absorbing film 2 performs an action absorbing a solar ray energy and adjusts transmittance of the visible light ray.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to heat-shielding glass.

[Prior Art] Heat ray blocking glass has traditionally been used to block solar energy from flowing into the interior of a building through window glass, suppress the rise in indoor temperature, and reduce the cooling load. Conventional heat-shielding glass is known in which several hundred thin films of oxides such as titanium oxide, tin oxide, etc. are formed on glass by spraying, CVD, dipping, or the like. Recently, only oxides have been produced using sputtering method (,
Thin films of metals, nitrides, etc. can now be formed freely over large areas. For this reason, single-layer film systems of transition metals such as chromium or titanium, metal/oxide films, two-layer film systems of nitride films/oxide films, oxide films/nitride films/oxide films, or Heat-shielding glass having a three-layer structure of oxide film/metal/oxide film, or a multilayer structure of more than that, has also come to be used.

Unlike a single-layer film, a heat-shielding glass having a multi-layer structure of three or more layers allows the reflectance and reflection color tone to be selected quite freely by utilizing interference. For this reason, demand is increasing for architectural applications where design is important.

In addition, heat-reflecting glass called Low-E glass (low-emissivity glass) is also known, which prevents the indoor temperature from dropping by reflecting heat rays from the room and reduces the heating load. .

This is oxide film/Ag/oxide film or oxide film/Ag
It has a laminated film with the following structure: /oxide film/Ag/oxide film, and is mainly used in cold regions. However, since it uses an Ag film, it is inferior in durability.

For this reason, laminated glass or double-glazed glass is used to prevent the laminated film from being exposed to the outside. This Low-
Since E-glass also has the effect of blocking heat rays from sunlight, it is also used in some automobile glasses for this purpose.

[Problem to be solved by the invention] Heat-shielding glass in which a film of oxides such as titanium oxide or tin oxide is formed on glass by conventional spraying, CVD, or dipping methods can be manufactured at low cost and with high productivity. On the other hand, compared to metal or alloy-based single-layer or multi-layer heat-shielding glass formed by recent sputtering methods, its heat-shielding performance is somewhat inferior, and tin oxide is weak against acids (and chemically stable). The problem was that it was not sufficient.

In addition, single-layer heat-shielding glass made of transition metals such as chromium and titanium generally has a high visible light reflectance Rv of 10 to 50%, and the reflective colors are bronze, blue-green, gray gold, silver, etc. from a design perspective. It's colored. Moreover, the visible light transmittance Tv is also as low as 10 to 60%. Therefore, natural colors, i.e. neutral colors and low reflectance,
In addition, it was unsuitable for application to window glasses for automobiles or general households, which require a visible light transmittance of 70% or more. In addition, such single-layer metal films do not have sufficient durability such as scratch resistance and chemical stability, and are not suitable for use in automobiles, etc.
It was impossible to use a single plate in applications where the operating environment was harsh.

In addition, the aforementioned type of Low-E glass has a relatively neutral reflective color and a visible light transmittance of 70% or more, but since it uses an Ag film, it has insufficient scratch resistance. The drawback was that it could not be used as a single sheet and had to be laminated or double-glazed.

In addition, conventional two-layer heat-shielding glasses such as metal/oxide film or nitride film/oxide film have not been able to provide neutral color tone, durability, high transmittance, and low reflectance. There wasn't.

In addition, heat ray blocking glass with a three-layer structure in which a film made of metals such as titanium, zirconium, chromium, or nitrides of these metals is sandwiched between high refractive index oxide films also has sufficiently good heat ray blocking performance. It is possible to adjust the thickness of the oxide film and use light interference to suppress the reflectance of visible light and increase the visible light transmittance to 70% or more, and the outermost layer is an oxide film. Although it is suitable as a single-pane heat-shielding glass because of its excellent durability, it can also cause blue color due to light interference.
The problem is that it takes on a pink or yellow color, making it difficult to obtain a natural and neutral appearance.

In this way, it has high durability that can be used as a veneer,
A heat-shielding glass that has a high visible light transmittance (particularly 70% or more so that it can be used as an automobile window glass) and is neutral in both transmittance and reflective color has not been obtained.

[Means for Solving the Problems] The present invention has been made to solve the above-mentioned problems, and is a heat-shielding glass in which at least two layers, a heat-absorbing film and an oxide film, are sequentially laminated on a transparent substrate. The present invention provides a heat ray blocking glass characterized in that the oxide film is the outermost layer on the air side and has a refractive index of 2.0 or less.

FIG. 1 shows a cross-sectional view of an example of the heat ray blocking glass of the present invention, where 1 is a transparent substrate, 2 is a heat ray absorbing film, and 3 is an oxide film having a refractive index of 2.0 or less.

The most significant feature of the present invention is that an oxide film having a refractive index of 2.0 or less is formed on the outermost layer on the air side. When the refractive index of the oxide film in the outermost layer on the air side exceeds 2.0, the visible light reflectance becomes thick (as a result, the visible light transmittance becomes low, and a visible light transmittance of 70% or more is easily achieved). Therefore, the refractive index of the oxide film 3 is preferably 2.0 or less, preferably 1.8 or less, particularly 1.7 or less.

The film material for the oxide film 3 is not particularly limited as long as it is highly durable and has a refractive index of 2.0 or less, but may include an oxide containing at least one of boron or silicon and zirconium, tin oxide, or A suitable example is silicon oxide.

At least one of boron or silicon, and zirconium, titanium, hafnium, tin, and tantalum.

The oxide film containing at least one kind of indium is
Since it is amorphous, it not only has very good wear resistance, but also has excellent acid and alkali resistance, making it ideal for applications that require particularly high durability.

Table 1 specifically shows the properties of various amorphous oxide films that are optimal for the oxide film of the present invention. Films were formed by reactive sputtering using targets with the compositions listed in the table. Crystallinity was observed by thin film X-ray diffraction. In addition, the scratch resistance is the result of a rubbing test using a sand eraser, where ○ indicates that there were almost no scratches, and × indicates that scratches occurred easily.

As for wear resistance, as a result of a taper test (wearing wheel C5-10F, load 500 g, 1000 rotations), a haze within 4% was rated O, and a haze exceeding 4% was rated x. Acid resistance was determined by immersion in 0.1N ngso4 for 240 hours.
○ indicates that the change rate of T, (visible light transmittance), and Rv (visible light reflectance) from before immersion is within 1%; △ indicates that the film has dissolved and disappeared from 1 to 4%. Marked things as ×. Alkali resistance is 0. As a result of immersion in IN NaOH for 240 hours, the rate of change in Tv and Rv from before immersion was 1%.
Those within 2% were rated as ○, those within 2% were rated as △, and those in which the film had dissolved were rated as ×. The boiling test is 1 atm, 10
After being immersed in water at 0°C for 2 hours, if the rate of change in Tv and Rv from before immersion is within 1%: 0% If over 1%: ×
And so.

An oxide ZrBxOy containing zirconium and boron, an oxide Zr5ixOy containing zirconium and silicon, and an oxide ZrBxSi*O containing zirconium, boron, and silicon.

Regarding the optimum composition of a film consisting of B (boron), Si (silicon), and 0 (oxygen), Z
The atomic ratio to r (zirconium) is
+y, the range is as follows.

As is clear from Table 1, 1.0 for ZrBxOy
It is preferable that ≦X* If x < 1.0, the refractive index of the film will exceed 2.0, and the visible light transmittance will be 7.
This is because it is difficult to obtain heat ray blocking of 0% or more. On the other hand, as X increases, the refractive index of the film decreases (see Figure 2 (a)), so there is no particular restriction on the upper limit of X. But, X
≧2.3 The acid resistance decreases, and when X≧4, the alkali resistance decreases and deterioration occurs in the boiling test.
It is preferable that x<2.3, and y is not particularly limited, but ZrO* and B! 0. Considering it as a complex system of
When expressed as Zr0g+ x BO+, s, y=2+1.
It is preferable that y be about 5x, that is, 2.5≦, y<5.45.

Zr51! Regarding the 011 film, as with the ZrBxOy film, the refractive index decreases as 2 increases (Fig. 2(b)).
), SL has a higher contribution to the refractive index reduction than B, so a smaller amount than B makes n=2.0 or less,
It is preferable that 0.28≦2. The upper limit is not particularly limited, but if it is 22:19, the alkali resistance of the membrane will be insufficient and the advantage of containing Zr will not be recognized so much, so it is preferable that 0.28≦z<19.

Regarding y, considering a composite system of ZrO□ and SiO□, it is preferable that y=2+2Z or so, that is, 2.56≦y<40.

Regarding the ZrBxSixO film, similarly, from the viewpoint of refractive index, it is preferable that 0.28≦X+Z. Similarly, there is no particular upper limit, but since alkali resistance is good if x+z<19, it is preferable that 0.28≦x+z<19 for ZrBmSi, Oy films.

However, as mentioned above, B2O3 is hygroscopic and dissolves when it absorbs moisture in the air, so Z r B * S
It is better not to contain too much in the t x Oy film.

Specifically, in the film, Zr other than 0 (oxygen),
B, Zr<25 atomic% with respect to the total of St, and S
If B is included so much that the remainder is 8 when t<25 atomic %, the chemical durability will be insufficient. That is, ZrBxSizO
, Zr:B:Si (atomic ratio) in the film is 1:x:z
Then, l/(1+x+z) <0.25 and z/
(1+x+z)<0.25, i.e. x+z-3>0,
In addition, the composition of X-3z+1>O has unfavorable chemical durability. For the same reason as mentioned in the case of ZrBxOy, y is the same as ZrO* + BgOs + SiO
Considering the composite system of □, it is preferable that y is approximately 2+1.5x+2z. Therefore, it is preferable that approximately 2.5≦y×40. The higher the content of B and St, the higher the Z
The refractive index of the rBxSixOy film decreases (Fig. 2(e)
reference).

From the above, as the oxide film 3 of the present invention, the oxide film containing at least one of boron and silicon and zirconium is a ZrBxOy film (1,0≦x<2.3.2.5
≦y < 5.45), Zr5ixOy film (0,2
8≦z<19.2.56≦y<40), ZrBxS
izOy film (0,28≦x+z<19.2.5≦y<4
o, except for x+z-3>O and x-3z+1>O) is particularly preferred.

These films were made of ZrB, 0. x>0.10 for membranes;
ZrSi, 0. For membranes Z≧0,05, Zr5ix
Regarding the Oy film, if X+Z≧0.05, the film becomes amorphous and has excellent wear resistance.

An oxide containing at least one of Ti, B, and Sl can also be used as the oxide of the present invention. In this case, from FIG. 2(d), for the T i S 1 z Oy film, the refractive index is 2 or less when 2≧0.56.

The oxide film containing zirconium and at least one of boron or silicon is a mixture of zirconium, boron, and silicon;
Since it is possible to easily coat a large area using a reactive sputtering method using direct current from a sintered target such as zirconium boride or a mixture thereof, it is suitable for applications such as automobiles and architecture.

Although tin oxide has a relatively large refractive index of 1.9 and somewhat insufficient acid resistance, it has excellent performance in other respects, and can be coated using DC sputtering. Therefore, it is suitable for applications that require large areas and low acid resistance.

In addition, silicon oxide has a low refractive index of approximately 1.5, although its alkali resistance is somewhat insufficient (it also has excellent abrasion and scratch resistance, so it requires particularly low reflectivity). It is ideal for applications such as

Above, as the oxide film 3 of the air-side outermost layer of the heat-shielding glass of the present invention, an oxide film containing at least one of boron or silicon and zirconium, a tin oxide film, and a silicon oxide film have been mentioned, but in particular, only these are mentioned. It is not limited to, and
These oxide films may contain other components in order to improve durability, adjust optical constants, improve stability during film formation, or improve film formation speed. Further, the oxide film 3 of the present invention does not necessarily have to be completely transparent, and may be an absorbent film in an oxygen-deficient state, or may partially contain nitrogen or carbon.

The thickness of the oxide layer 3 is not limited, but if it is too thin, sufficient durability cannot be obtained, so it is preferably 50 Å or more, preferably IOO 8 or more, particularly 150 Å or more, although it depends on the application. On the other hand, if it becomes too thick, interference effects will occur and the reflected color will become strong (although it depends on the refractive index).
000 Å or less, preferably 700 Å or less, especially 500 Å
It is preferable that it is below.

The film material of the heat ray absorption film 2 is not particularly limited, and may be metal, carbide, oxide, or
Or selected from these composite membranes. Specifically, a film containing one of titanium, chromium, zirconium, tantalum, hafnium, titanium nitride, chromium nitride, zirconium nitride, tantalum nitride, and hafnium nitride as a main component is preferable because it has good heat ray absorption performance.

The thickness of the heat ray absorbing film 2 should be set to be too thick (as this will reduce the visible light transmittance), the type of substrate 1,
Although it depends on the refractive index and film thickness of the oxide film 3, it is desired that the thickness is 1000 Å or less, preferably 800 Å or less. If the number exceeds 800, the internal stress will increase, especially in the case of a nitride film, and the film will likely peel off. In addition, if it is too thin, sufficient heat ray absorption performance cannot be obtained, so it depends on the thickness and type of the film material and the substrate glass, but it is preferably 20 Å or more, preferably 20 to 1
00 people is preferable.

Furthermore, the method of forming the oxide layer 3 and the heat ray absorbing film 2 is not particularly limited, and vacuum evaporation, ion blasting, sputtering, etc. are possible, but if large area coating is required, , a reactive sputtering method is preferred since it has excellent uniformity.

As the transparent substrate l, glass, plastic, etc. are usually used.

In the present invention, neutral color tone means one having the following characteristics. In other words, when expressed in the CIH color system, the changes in the X and Y points before and after the formation of a heat ray absorbing film, oxide film, etc. on the substrate surface are expressed as ΔX,
Let it be Δy. J((Δx)”+(Δy)2) is the color tone change due to film formation, and a neutral color is defined as a value of this color tone change of 0.008.0.032 for each of the transmitted color and reflected color. The following is more preferable: GEE
It means that it is 0,007,0,028 or less. however,
Regarding the reflected color, since the reflected color is different between the surface on which the coating is formed and the surface on which the coating is not formed, the one with the larger value is used.

When the heat ray absorption film 2 is a nitride film, an oxide film may be formed between the glass substrate and the nitride film in order to reduce internal stress and increase adhesion to the glass substrate. good. Another effective method to increase adhesion to the glass substrate is to first form a base film on the glass substrate, then implant high-energy ions, and then form a heat ray absorbing film. be. For example, if a titanium film is formed as a base film and then a titanium nitride film is formed after high-energy nitrogen ions are implanted, a titanium nitride film with very high adhesion can be obtained as the heat ray absorbing film 2.

"Function" In the heat ray blocking glass of the present invention, the air-side outermost oxide film 3 performs an optical function due to its refractive index, film thickness, etc. That is, it reduces the reflectance of the heat ray blocking glass and contributes to improving the visible light transmittance, and also has the effect of reducing the stimulating purity of the reflected color and neutralizing the overall color tone. Further, the oxide film 3 has the role of a protective film for improving the abrasion resistance and chemical resistance of the heat ray blocking glass.

The heat ray absorbing film 2 functions to absorb sunlight energy and also adjusts visible light transmittance.

In addition, when the oxide film 3 is an oxide film containing at least one of boron or silicon and zirconium, it has the effect of lowering its refractive index, and the zirconium oxide film lacks such boron or silicon. It also has the effect of improving wear resistance. This is thought to be because the addition of boron or silicon, which is a glass component, makes the film amorphous and increases the surface smoothness, which lowers the frictional resistance and improves the wear resistance. Due to such amorphization,
Abrasion resistance can be added to zirconium oxide, which has strong chemical stability against acids and alkalis, creating a highly durable film that has both abrasion resistance and chemical stability. contributes to

[Example] Example 1 A glass substrate was set in a vacuum chamber of a sputtering device.
It was evacuated to X 10-' Torr. A 4 mm thick blue plate was used as the glass substrate. Similar glass substrates were used in Example 2 and subsequent examples. After introducing a mixed gas of argon and nitrogen to set the pressure to 2 X 10-'' Torr, titanium was reactively sputtered to form titanium nitride (first layer) of approximately 2OA.Next, a mixed gas of argon and oxygen The pressure was changed to 2 x 10-'' Torr, and about 200 oxide films (second layer) made of zirconium and boron were formed by reactive sputtering of a ZrB snow target.

Visible light transmittance Tv of the heat ray blocking glass thus obtained
, sunlight transmittance Tts coated surface visible light reflectance Rvr
, glass surface visible light reflectance Rva, color tone change of transmission and reflection J((Δx)”+(Δy)2) is 71.5, respectively.
6.13.12 (%), 0.006g.

It was 0.026.

Furthermore, the transmitted and reflected colors were so neutral that they were almost indistinguishable from the original glass.

To examine the durability of the film, it was immersed in 0.1 N hydrochloric acid or sodium hydroxide at room temperature for 6 hours, or in boiling water for 2 hours, but no change was observed in the optical performance. acid,
When immersion in alkali was further continued and evaluation was made in the same manner after 240 hours had elapsed, TV%Tt had increased by 2 to 3%, indicating deterioration.

Even in a scratch test with a sand eraser, there were almost no scratches, showing extremely excellent scratch resistance.

Example 2 Zirconium nitride (first layer) was deposited on a glass substrate by reactive sputtering in the same manner as in Example 1.
After forming 0 layers, the gas was switched to a mixed gas of argon and oxygen at 2 x 10-'' Torr.Next, a ZrB1 target was reactively sputtered to form an oxide film (second layer) consisting of zirconium and boron for about 200 layers. did.

Optical performance Tv, Tts of the obtained heat ray blocking glass
Rvrs Rva, transmission and reflection color tone changes are each 7
1.55.12.12 (%), 0.0067, 0.02
It was 6.

In order to examine the durability of the example membranes, they were immersed in 0.1 N hydrochloric acid and sodium hydroxide aqueous solutions at room temperature for 6 hours or in boiling water for 2 hours, but no change was observed in the optical performance. A durability test similar to No. 1 was conducted, and similarly excellent performance was shown.

Example 3 After forming about 10 chromium nitrides (first layer) by reactive sputtering of chromium on a glass substrate in the same manner as in Example 1,
Switch to mixed gas of argon and oxygen 2 x 10-”
I set it to Torr. Next, a target containing ZrBz and SiC was reactively sputtered to form zirconium, boron,
Approximately 200 people formed an oxide film (second layer) containing silicon. Optical performance TV, Tg, RvF of the obtained heat ray blocking glass
, Rva, transmission, and reflection color tone changes are each 72. 5
g, 10°9 (%), 0.0074.0.029
Met. The transmitted and reflected colors were almost indistinguishable from the base plate. The durability was also extremely excellent as in Example 1.

Example 4 Chromium was used as the first layer instead of titanium nitride in Example 1.
Approximately 10 people each formed titanium and zirconium. On top of that, a ZrB* target is reactively sputtered to form an oxide film (second layer) containing zirconium and boron with a thickness of approximately 200 mm.
We created three types of heat-shielding glass by forming people. These Tv, Tg, RVF% RVO did not show any big difference in the first layer of chromium, titanium, and zirconium, and each was 7.
It was 2.58.11.10 (%). Transparent color 1
Reflection color has a color tone change of 0.0031 to 0.006, respectively.
5.0.028 to 0.030, which was extremely excellent as in Example 1. Further, the durability was also extremely excellent as in Example 1.

Example 5 As in Example 1, 20 titanium nitride layers were formed, and then 200 layers were formed by reactive sputtering of tin. The thus obtained heat ray blocking glass had TV, TIE, RVF, and Rvo of 70.55.15°13 (%), respectively.

Except for the fact that the membrane dissolved during long-term storage in a 0.1N HCI aqueous solution, it had excellent durability. As for the color tone, except for the slightly higher reflection, the color tone change of the transmitted color and reflected color is 0.
．． 0036.0.030, a neutral color.

Example 6 After 20 layers of titanium nitride were formed in the same manner as in Example 1, 250 layers of silicon oxide were formed by high frequency reactive sputtering. TV, TE, R of the heat ray blocking glass thus obtained
vF%Rvo was 73 and 56.8.6 (%), respectively.

Except for the fact that the film was dissolved in the 0.1N NaOH aqueous solution for a long time, the durability was excellent. Low reflectance, transmission,
The color tone was also extremely excellent, with a color change in reflection of 0.005.0.018.

Example 7 After forming 20 titanium nitrides in the same manner as in Example 1, a zirconium-boron alloy target (composition is 50Zr in atomic concentration) was prepared.
-50B) was reactively sputtered to form an oxide film (second layer) consisting of zirconium and boron.

Optical performance TV, TE, Rv□ of the obtained heat ray blocking glass
Rvo is 72.3.5g for transmission and reflection color tone each.
, 5.10.4.8.8.0.0024.0.0290
Met. The transmitted and reflected colors were almost indistinguishable from the material. To check the durability of the membrane, 0.1N hydrochloric acid,
Although it was immersed in each sodium aquatic solution at room temperature for 240 hours or in boiling water for 2 hours, no change in optical performance was observed. From this, it was found that excellent durability was shown in a more severe durability test than in Example 1. It also showed excellent scratch resistance in a sand eraser rubbing test.

Example 8 After forming 20 titanium nitride layers in the same manner as in Example 1, ZrSi
Approximately 200 people formed an oxide film (second layer) consisting of zirconium and silicon by reactive sputtering using a target.

Optical performance Tv, 1st section, RvF of the obtained heat ray blocking glass
, Rvo is 73.7 for transmission and reflection color tone changes, respectively.
．． 59.3.8.6.7.1.0.0010゜0.01
It was 75. The durability of the film was evaluated under the same conditions as in Example 7, and it showed similarly excellent performance.

Example 9 After forming 20 titanium nitrides in the same manner as in Example 1, a zirconium-silicon alloy target (composition is 1OZr in atomic concentration)
-90Si) was reactively sputtered to form an oxide film (second layer) of zirconium and silicon.

Optical performance TV, TE, RvF of the obtained heat ray blocking glass
%RVQ is 74.3.5 for transmission and reflection color tones, respectively.
9.6.8.0.6.3.0.000g, 0.007
It was 4.

The durability of the film was evaluated under the same conditions as in Example 7, and it showed similarly excellent performance.

[Effects of the Invention] The heat-shielding glass of the present invention has at least a two-layer structure in which a heat-absorbing film and an oxide film with a refractive index of 2.0 or less are laminated on a transparent substrate. It has a good color tone, high visible light transmittance, and high durability.

Therefore, even as a veneer, it can be used satisfactorily in applications with severe operating environments, such as in construction and automobiles.

When an oxide film containing zirconium and at least one of boron or silicon is formed as the oxide film 3, a heat-shielding glass particularly excellent in abrasion resistance and chemical resistance can be obtained.

By increasing the content ratio of boron, silicon, or the total amount thereof, it is possible to reduce the refractive index of the oxide film to 1.7 or less, resulting in low visible light reflection, high transmission,
Heat-shielding glass with a neutral color tone becomes possible.

Furthermore, when an oxide film or a tin oxide film containing at least one of boron or silicon and zirconium is used as the air-side outermost layer 3, a large area is required because the film can be formed by direct current sputtering. It is ideal for automotive, architectural, and other applications.

In addition, when using a silicon oxide film as the outermost layer 3 on the air side, direct current sputtering is difficult, but since the silicon oxide film has a low refractive index, it has a neutral color tone and extremely low visible light reflectance (transmittance is low). It is possible to create a glass that blocks high heat rays.Also, since the visible light reflectance is low, even if it gets scratched, it will not be noticeable.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an example of the heat ray blocking glass of the present invention. FIG. 2(a) is a diagram showing the relationship between the content of B in the ZrBxOy film and the refractive index n of the film. Figure 2(b) shows Zr
Figure 2 (c) shows the relationship between Si, o, Si content in the film and n, Z r B + S 1 ! Si in Oy film
Figure 2(d) shows the relationship between the content of Ti and n.
FIG. 3 is a relationship diagram between the St content and n in a 5xzOy film. 1: Transparent substrate, 2: Heat ray absorption film, 3 Dioxide film No. 1 Fig. 50 00 Fig. (a) Fig. (c) 2rSilOx Moon center cp) 21o2+s. 2(-
Ltv'/a) Figure 2 cb) Figure (cl)

Claims (6)

[Claims] (1) A heat-shielding glass in which at least two layers, a heat-absorbing film and an oxide film, are sequentially laminated on a transparent substrate, and the oxide film is the outermost layer on the air side;
．． A heat ray blocking glass characterized by having a refractive index of 0 or less. (2) The heat ray blocking glass according to claim 1, characterized in that the visible light transmittance is 70% or more. (3) Claim 1 or 2, wherein the oxide film is made of an oxide containing at least one of boron or silicon and at least one of zirconium, titanium, hafnium, tin, tantalum, and indium.
Heat-shielding glass as described. (4) The heat ray blocking glass according to claim 1 or 2, wherein the oxide film is made of an oxide whose main component is tin oxide. (5) The heat ray blocking glass according to claim 1 or 2, wherein the oxide film is made of an oxide whose main component is silicon oxide. (6) The heat ray absorbing film has as a main component one or more selected from the group of titanium, chromium, zirconium, tantalum, hafnium, titanium nitride, chromium nitride, zirconium nitride, tantalum nitride, and hafnium nitride. The heat ray blocking glass according to any one of claims 1 to 5.