JPH08283044A - Heat ray cutoff glass - Google Patents

Abstract

PURPOSE: To obtain a heat ray cutoff glass capable of suitably use at a position required high visible ray transmissions and excellent heat ray cutoff performance. CONSTITUTION: This heat ray cutoff glass is provided with a multiple tungsten oxide film 2 incorporating at least one kind metal element selected from the group consisting of group IIIa, IVa, Vb, VIb, and VIIb in periodic table as a first layer from a substrate 1 side on the transparent substrate 1 and a transparent dielectric film 3 as a second layer on the first layer 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat ray-shielding glass suitable as a window glass, and more particularly to a heat ray-shielding glass which can be suitably used in a region where high visible light transmittance and good heat ray-shielding performance are required. .

[0002]

2. Description of the Related Art Conventionally, from the viewpoint of energy saving, a specific wavelength portion of sunlight radiated into a passenger compartment through a window glass is blocked to reduce a temperature rise in the passenger compartment and a load on a cooling device. Therefore, a window glass having a high heat ray shielding property is required.

As a method of blocking heat rays, a transparent conductive film typified by a mixed film of indium oxide and tin oxide (ITO film) or a zinc oxide film added with aluminum is formed on a transparent substrate called a so-called drude mirror. A method of forming a film to block heat rays is known. This type of glass blocks heat rays, but has a wavelength of 1.5 μm or more, which is not very good.

Further, it is known that various metal films are laminated to combine a drude mirror effect with an optical interference effect to reflect or transmit light of a specific wavelength. As this heat ray reflective film, for example, a structure in which a silver film is sandwiched between transparent dielectric films is proposed (Japanese Patent Publication No. 47-6315), and a structure in which a nitride film is sandwiched between transparent dielectric films is proposed. (JP-A-63
-206333 publication).

[0005]

However, the heat ray reflective film described in the above publication has a drawback that it cannot yet exhibit satisfactory performance. Further, when a silver film is used, the silver film has a sheet resistance value of about several Ω−10 Ω / □, and has a high radio wave blocking property. Therefore, when such a conductive film is used as the heat ray blocking glass, the mobile phone is used in a field where it is necessary to transmit the radio wave in order to block the radio wave, for example, in the interior of an automobile or in a building where a radio or TV is installed. However, there was a problem that it was not possible to use radio, television, etc.

When used as architectural glass, it is said that the window glass affects the radio field intensity in the surroundings such as in high-rise buildings. Further, when a conductive heat ray blocking film is formed on the glass surface provided with the antenna wire, a current flows between the antenna wires and the antenna performance is deteriorated, as disclosed in JP-A-3-122032. There was a problem. Further, although depending on the conductivity of the heat ray blocking film, if the conductivity is good, the problem of radio wave transmission will occur in addition to the problem that the antenna performance is deteriorated.

As described above, a heat shield film such as a drew demirror type or a silver film is not preferable. Therefore, an object of the present invention is to provide a heat ray-shielding glass that can shield heat rays with a simple layered structure and can transmit radio waves without problems.

[0008]

SUMMARY OF THE INVENTION The above-mentioned object of the present invention is to provide a transparent substrate on which a first layer from the substrate side is a group IIIa, IVa, Vb, VIb and VII of the periodic table.
A heat ray shield, comprising: a composite tungsten oxide film containing at least one metal element selected from the group consisting of group b; and a transparent dielectric film as a second layer provided on the first layer. Achieved by glass.

The present invention will be described in more detail below. FIG.
Shows the constitution of the heat ray shielding glass of the present invention. In FIG. 1, 1 indicates a transparent substrate. For this transparent substrate,
Appropriately selected from various glass plates such as soda lime glass and aluminosilicate glass, colored glass plates such as gray, blue, bronze and green, or transparent resin substrates such as polymethylmethacrylate (PMMA) and polycarbonate (PC). However, various glass plates and colored plates are preferable, and glass having a green color is more preferable.

The color of glass having a green color can be defined by a chromaticity diagram of Yxy display. Y is 1.00
It is preferable that the range is 1.40, x is 0.24 to 0.32, and y is 0.30 to 0.41. The green glass in this range has a high visible light transmittance and an absorption in the near-infrared region, so that the heat insulating effect is remarkably improved by the combined use with the above-mentioned heat ray blocking film. Further, glass having a greenish tint contains iron ions, and exhibits excellent heat insulating performance due to a synergistic effect with the tungsten oxide heat insulating film of the present invention.

In FIG. 1, 2 is a group IIIa, IVa of the periodic table provided on the transparent substrate 1 as a first layer.
It is a composite tungsten oxide film containing at least one metal element selected from the group consisting of Group Vb, Group VIb and Group VIIb.

Reference numeral 3 is a transparent dielectric film provided as a second layer on the composite tungsten oxide film which is the first layer.
The transparent dielectric film 3 is an oxide film of at least one metal selected from the group consisting of zinc, aluminum and zirconium (hereinafter referred to as a specific oxide film).

The refractive index of the specific oxide film 3 is preferably lower than that of the composite tungsten oxide film 2. When the refractive index is lower, the optical interference effect of the two layers of the composite tungsten oxide film 2 and the specific oxide 3 can be effectively used, and the heat ray blocking effect can be improved.

In the present invention, the function of blocking heat rays is mainly the IIIa group, the IVa group, the Vb group and the VI group of the periodic table.
Due to optical interference caused by the composite tungsten oxide film containing at least one metal element selected from the group consisting of b-group and VIIb-group.

Generally, tungsten has a hexavalent valence in the most oxidized state in the tungsten oxide film.
In this state, the tungsten oxide film is transparent and has no ability to block heat rays. In the presence of pentavalent tungsten which is slightly reduced from the most oxidized state, absorption occurs in the near infrared region. By utilizing this absorption, heat rays can be blocked. Tungsten oxide having this absorption has an oxygen / tungsten atomic ratio in the range of 2.50 to 2.98.
If the ratio is outside this range, infrared absorption cannot be expected.

It is known that the durability of tungsten oxide is generally not sufficient though it depends on the manufacturing method. Further, the conductivity is in the range of several kΩ / □ to several tens of kΩ / □ depending on the film thickness, and is not a sufficiently high resistance film in view of the above-mentioned problems of the antenna and radio wave transparency.

According to the present invention, a group IIIa, a group IVa, a group Vb, a group VIb and a group VI of the periodic table are provided on a transparent substrate.
A composite tungsten oxide film containing at least one metal element selected from the group consisting of Group Ib is used. This composite oxide film essentially has strong light absorption in the infrared region of tungsten oxide.

IIIa group, IVa group, Vb of the periodic table
At least one metal element selected from the group consisting of Group VI, Group VIb and Group VIIb coexists with tungsten oxide as a stable oxide in the composite tungsten oxide film, and improves poor durability of tungsten oxide alone. At the same time, it has a function of increasing the resistance of the tungsten oxide film to several hundreds kΩ / □ to several hundreds MΩ / □.

Preferably, A1 is used as the group IIIa, Si is used as the group IVa, V or Nb is used as the group Vb, Cr is used as the group VIb, and Mn is used as the group VIIb.
The content of these elements is 5 to 15 with respect to tungsten.
It is preferably contained in the range of atomic ratio. This is because it is easy to produce an alloy target for a complex oxide, and is not necessarily limited to the above elements. The refractive index of the composite tungsten oxide film is preferably in the range of 1.9 to 2.8.

These heat ray blocking films can be appropriately selected and used from known film forming methods, for example, sputtering method, vapor deposition method, ion plating method, chemical vapor deposition method (C
The film can be formed by a vacuum film forming method such as a VD method) or a wet film forming method such as a sol-gel method, but it is particularly preferable to form the film by a sputtering method from the viewpoints of increasing the area and productivity.

The complex oxide can be formed by, for example, the following sputtering method. As a sputtering target, tungsten and IIIa group, IVa group, Vb group of the periodic table,
An alloy target containing at least one metal element selected from the group consisting of VIb group and VIIb group at a predetermined concentration is used, and argon (Ar) and oxygen (O ₂ ) are adjusted as a sputtering gas at a predetermined gas ratio. Using a mixed gas of
A complex oxide film can be formed on a glass substrate by a so-called reactive sputtering method.

The refractive index of the composite tungsten oxide film is 1.
Although it is in the range of 9 to 2.8, when a structure in which a transparent dielectric film having a lower refractive index is laminated on this film, an optical interference effect appears, the transmittance in the visible region is increased, and the infrared region is increased. The reflection of is increased and the heat ray can be absorbed and reflected at the same time. With such a structure, the heat ray blocking effect is further enhanced, and the present invention is achieved. In addition, the uppermost transparent dielectric film 3 also has an effect as a protective film against the problem of oxidation and scratch of the composite tungsten oxide film 2.

The film thickness of each layer is not limited as long as it is a thickness at least capable of exhibiting the heat ray blocking function of the composite tungsten oxide film 2, but is particularly 2 to 200 nm.
It is preferably in the range of. When the film thickness of the composite tungsten oxide film 2 is less than 2 nm, the film becomes island-shaped, and conversely, when it exceeds 200 nm, the economy is poor. In addition to both of these, in order to obtain stable and reliable performance in the entire film structure, the range of 5 to 150 nm is preferable.

The specific oxide film 3 is not limited as long as it has a thickness capable of exhibiting an optical interference effect with the composite tungsten oxide film 2, but it is particularly preferably in the range of 2 to 100 nm. If the film thickness of the specific oxide film 3 is less than 2 nm, the film becomes island-shaped, and conversely, if it exceeds 100 nm, the economy is poor. In addition to both of these, in order to obtain stable and reliable performance in the entire film structure, 5 to 80 n is required.
It is preferably in the range of m.

According to the heat ray-shielding glass of the present invention, heat rays can be efficiently shielded with a simple structure, and sufficient radio wave permeability can be obtained. Further, although the heat ray-shielding glass of the present invention can be used as a single plate, it goes without saying that it can be used as a laminated glass or a multi-layer glass.

[0026]

According to the present invention, a transparent substrate is provided with a group IIIa, a group IVa, a group Vb, and a group VIa of the periodic table as a first layer from the side of the substrate.
A composite tungsten oxide film containing at least one metal element selected from the group consisting of b-group and VIIb-group is provided, and a specific oxide film is provided as a second layer on the first layer. By using the heat ray-shielding glass, it is possible to obtain a window glass that effectively shields heat rays with a simple layer structure and has good radio wave transmission.

[0027]

EXAMPLES The present invention will now be described in more detail by way of examples, which should not be construed as limiting the invention.

Example 1 A transparent glass substrate was degreased and washed with isopropyl alcohol, rinsed with pure water, and then dried by nitrogen blowing. This transparent glass substrate was transferred into the sputtering device and transferred to 5 × 10 ^-6
Exhausted to Torr. In the vacuum chamber, a silicon-tungsten alloy target (Si: W = 0.05: 1 atomic ratio) for a silicon oxide-containing tungsten oxide film used as a heat ray blocking film of the composite tungsten oxide film 2 and a specific oxide film A zinc target for zinc oxide used as No. 3 was installed.

First, a mixed gas of argon and oxygen was adjusted as Ar: O ₂ = 30: 4 as a sputtering gas, and the exhaust speed and the gas pressure in the vacuum chamber were adjusted to 5 × 10 ^-3 Torr. Adjusting the gas flow rate, sputtering power 500W
Then, a tungsten oxide film 2 containing silicon was formed to a thickness of 50 nm by reactive sputtering. Next, as a sputtering gas, a mixed gas of argon and oxygen is Ar: O ₂ = 1:
Adjust so that the gas pressure in the vacuum chamber is 5 × 1.
The exhaust rate and the gas flow rate were adjusted so as to be 0 ⁻³ Torr, and a zinc oxide film was formed to a thickness of 70 nm as the specific oxide film 3 by reactive sputtering with a sputtering power of 400 W. The tungsten-containing film containing silicon had a refractive index of 1.9, and the zinc oxide film had a refractive index of 2.0.

The optical characteristics of the heat ray-shielding glass thus formed are: visible light transmittance 79%, sufficient visible light transmittance and visibility, and solar radiation transmittance 58%, sufficient heat ray of sunlight. Was shut off. Furthermore, the membrane resistance value at this time is 3
It was 0 MΩ / □, and when this glass was used as a window glass for buildings, a mobile phone could be used without any problems, and a radio could receive FM and AM radio waves satisfactorily. Further, even when used as a window glass for an automobile, the mobile phone can be used without any trouble, and the radio can receive FM and AM radio waves satisfactorily.

Example 2 Under the same film material and film forming conditions as in Example 1, instead of a transparent glass substrate, Y = 1.27, x = 0.856, y = 0.
A heat ray-shielding glass was prepared in exactly the same manner as in Example 1 except that a green glass having a value of 3176 was used, the thickness of the tungsten oxide film 2 containing silicon was 40 nm, and the thickness of the zinc oxide film 3 was 50 nm. Was deposited.

The optical characteristics of this constitution are a visible light transmittance of 77% and a sufficient visible light transmittance and visibility required for a window glass, and a solar radiation transmittance of 53% is sufficient for heat rays of sunlight. It was shut off. Further, when this glass was used as a window glass for buildings, the mobile phone could be used without any trouble, and the radio could receive FM and AM radio waves satisfactorily. Further, even when it is used as a window glass for automobiles, the mobile phone can be used without any trouble, and the radio can receive FM and AM radio waves satisfactorily.

Example 3 A film material different from those in Examples 1 and 2 will be described.
It The green glass substrate used in Example 2 was
Degreasing and cleaning with pure alcohol, rinsing with pure water, and then nitrogen
-Dry. Use this transparent glass substrate as a sputtering device
Transport, 5 × 10 ^-6Exhausted to Torr. Multiple in the vacuum chamber
Aluminum containing used as tungsten oxide film 2
Of aluminum and tungsten for tungsten oxide film
Alloy target (A1: W = 0.1: 1 atomic ratio), and
An aluminum oxide film used as the specific oxide film 3;
A luminium target was installed.

First, a mixed gas of argon and oxygen was adjusted as a sputtering gas so that Ar: O ₂ = 30: 4, and the exhaust rate and the gas pressure in the vacuum chamber were adjusted to 5 × 10 ⁻³ Torr. Adjusting the gas flow rate, sputtering power 500W
Then, an aluminum-containing tungsten oxide film having a thickness of 90 nm was formed by reactive sputtering. Next, as a sputtering gas, a mixed gas of argon and oxygen is adjusted so that Ar: O ₂ = 1: 1, and the argon gas is supplied at a gas pressure of 5 in the vacuum chamber.
The exhaust rate and the gas flow rate were adjusted so as to be × 10 ^-3 Torr, and an aluminum oxide film was formed to a thickness of 40 nm as the specific oxide film 3 with a sputtering power of 400 W. The aluminum-containing tungsten oxide film thus obtained had a refractive index of 2.1, and the aluminum oxide film had a refractive index of 1.6.

The optical characteristics of this structure are a visible light transmittance of 72%, sufficient visible light transmittance and visibility required for a window glass, and a solar radiation transmittance of 47% to sufficiently block the heat rays of sunlight. Was. Further, when this glass was used as a window glass for buildings, the mobile phone could be used without any trouble, and the radio could receive FM and AM radio waves satisfactorily. Further, even when it is used as a window glass for automobiles, the mobile phone can be used without any trouble, and the radio can receive FM and AM radio waves satisfactorily.

Example 4 As the composite tungsten oxide film 2 in Example 3, instead of the alloy target of aluminum and tungsten, an alloy target of chromium and tungsten (Cr: W = 0.
A heat ray-shielding glass was formed in exactly the same manner as in Example 3 except that a tungsten oxide film containing chromium was formed to a thickness of 80 nm using 1: 1). The refractive index of the chromium-containing tungsten oxide film was 2.4.

The optical characteristics of this constitution are a visible light transmittance of 71%, sufficient visible light transmittance and visibility required for a window glass, and a solar radiation transmittance of 47% to sufficiently block the heat rays of sunlight. Was. Furthermore, when this glass was used as a window glass for buildings, a mobile phone could be used without any trouble, and FM and AM radio waves could be satisfactorily received by a radio. Further, even when used as a window glass for an automobile, the mobile phone can be used without any trouble, and the radio can receive FM and AM radio waves satisfactorily.

Example 5 A 55 nm tungsten oxide film containing manganese was used instead of the silicon-containing tungsten oxide film as the composite tungsten oxide film 2 in Example 1, and a zirconium oxide film was used as the specific oxide film 3 instead of the zinc oxide film. 6
A heat ray-shielding glass was formed in the same manner as in Example 1 except that the thickness was set to 0 nm. The manganese-tungsten alloy target used at this time used Mn: W of 0.2: 1. The refractive index of the manganese-containing tungsten oxide film is 2.3.
And the refractive index of the zirconium oxide film was 1.9.

The optical characteristics of this structure are 77% of visible light transmittance and sufficient visible light transmittance and visibility required for a window glass, and 52% of solar radiation transmittance to sufficiently block heat rays of sunlight. Was. Further, when this glass was used as a window glass for buildings, the mobile phone could be used without any trouble, and the radio could receive FM and AM radio waves satisfactorily. Furthermore, even if it is used as a window glass for automobiles, the mobile phone can be used without any trouble, and the
We were able to receive M and AM radio waves satisfactorily.

Example 6 Instead of the transparent glass substrate in Example 5, Y = 1.3
A green glass having values of 0, x = 0.30, y = 0.38 was used, and a tungsten oxide film containing vanadium was used as the composite tungsten oxide film 2 instead of the tungsten oxide film containing manganese at 65 nm. Is
A heat ray-shielding glass was formed in the same manner as in Example 5.
The V: W of the vanadium-tungsten alloy target used at this time was 0.1: 1. The vanadium-containing tungsten oxide film had a refractive index of 2.2.

The optical characteristics of this structure are as follows: visible light transmittance of 74%, sufficient visible light transmittance and visibility required for a window glass, and solar radiation transmittance of 50% to sufficiently block heat rays of sunlight. Was. Further, when this glass was used as a window glass for buildings, the mobile phone could be used without any trouble, and the radio could receive FM and AM radio waves satisfactorily. Further, even when it is used as a window glass for automobiles, the mobile phone can be used without any trouble, and the radio can receive FM and AM radio waves satisfactorily.

Structure of Example Example 1: Glass / Si-containing tungsten oxide film (50
nm) / zinc oxide film (70 nm) Example 2: Green glass / Si-containing tungsten oxide film (40 nm) / zinc oxide film (50 nm) Example 3: Green glass / Al-containing tungsten oxide film (90 nm) / aluminum oxide film (40 nm) Example 4: Green glass / Cr-containing tungsten oxide film (80 nm) / Aluminum oxide film (40 nm) Example 5: Glass / Mn-containing tungsten oxide film (55)
nm) / zirconium oxide film (60 nm) Example 6: Green glass / V-containing tungsten oxide film (65 nm) / zirconium oxide film (60 nm)

[0043]

As described above, according to the heat ray-shielding glass of the present invention, a group IIIa, a group IVa, a group Vb, a group VIb and a group VIIb of the periodic table are provided as a first layer on the transparent substrate from the substrate side. Providing a composite tungsten oxide film containing at least one metal element selected from the group consisting of
By using a heat ray-shielding glass characterized in that a specific oxide film is provided as a second layer on the first layer, heat rays can be effectively blocked with a simple layer structure, and good radio wave permeability can be obtained. A window glass having is obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a film structure of a heat ray-shielding glass of the present invention.

[Explanation of symbols]

 1 transparent glass substrate 2 composite tungsten oxide film 3 transparent dielectric film

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Shibata 2 Takaracho, Kanagawa-ku, Yokohama, Kanagawa Nissan Motor Co., Ltd. (72) Riichi Nishide 2 Takara-cho, Kanagawa, Yokohama, Kanagawa Nissan Motor Co., Ltd. Within

Claims (5)

[Claims] 1. A transparent substrate on which at least one metal element selected from the group consisting of IIIa group, IVa group, Vb group, VIb group and VIIb group of the periodic table is provided as a first layer from the substrate side. Providing a composite tungsten oxide film containing
A heat ray shielding glass comprising a transparent dielectric film as a second layer provided on the first layer. 2. The heat ray-shielding glass according to claim 1, wherein the transparent dielectric film is an oxide film containing at least one metal selected from the group consisting of zinc, aluminum and zirconium. 3. The composite tungsten oxide film has a refractive index of 1.
The heat ray-shielding glass according to claim 1, which is in a range of 9 to 2.6. 4. The refractive index of the transparent dielectric film is 1.4 to 2.2.
The heat ray-shielding glass according to claim 1 or 2, characterized in that 5. The heat ray-shielding glass according to claim 1, wherein the composite tungsten oxide and the transparent dielectric film are formed by a sputtering method.