JPH0859298A - Heat insulating film - Google Patents

Abstract

PURPOSE: To obtain glass having durability, high light transmissivity in visible ray region, low light transmissivity in infrared ray region and excellent in heat insulating effect by forming a complex oxide film comprising one or more kinds of elements selected from a group consisting of groups IVa, IIIa, VIIb, VIb and Vb onto a glass substrate. CONSTITUTION: A glass substrate having 1.0-1.4 Y value, 0.24-0.32 x value and 0.3-0.41 y value on chromaticity diagram is used as the glass substrate. A complex oxide film is formed by the following sputtering method. An alloy target containing one or more kinds of elements selected from tungsten and the above groups from IVa to Vb of the periodic table in a prescribed concentration is used as a sputtering target and a mixed gas of argon with oxygen controlled to a prescribed gas ratio is used as a sputtering gas and the complex oxide film is formed on the glass plate by a reactive sputtering method. The thickness of the film formed thereon is normally limited to <=1μm. A silicon hard film may be formed as a protective film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat insulating film having a heat insulating function and a radio wave transmitting property suitable as a window glass for automobiles and buildings, and particularly, it has sufficient visible light transmittance, good heat insulating performance and durability. In addition, the present invention relates to a heat insulating film that can be suitably used as a window glass for automobiles and buildings as a glass having a better radio wave transmission property.

[0002]

2. Description of the Related Art Conventionally, from the viewpoint of energy saving, a specific wavelength portion of sunlight radiated indoors through a window glass is cut off to reduce the temperature rise in the room and reduce the load on the cooling equipment. The window glass with high heat insulating property is required in order to reduce the solar radiation and further reduce the solar radiation to the human body.

As a method of blocking heat rays, there has been known a method of blocking a specific wavelength portion by utilizing a light interference effect by laminating dielectric films having different refractive indexes in multiple layers. However, in this method, the dielectric film is
By stacking 0 or 20 layers, ideal wavelength selectivity can be imparted, so that it can be used as an optical component or element requiring a large number of layers, but as a window glass. It cannot be used industrially.

Further, as another method for blocking heat rays, an ITO film or Al-doped Z, which is a so-called drude mirror, is used.
A method of blocking heat rays using a transparent conductive film typified by an nO film is known. However, these films block light of 1.5 μm or more in sunlight, but transmit light of wavelengths shorter than that, and are not sufficient as heat insulating performance.

Further, there is known a heat insulating film which utilizes a light interference effect by sandwiching a metal film typified by a silver film between dielectrics as disclosed in Japanese Patent Publication No. 47-6315. However, since this type of insulating glass uses a silver film that easily oxidizes, it is difficult to use it when it is formed on the glass alone, and it is usually necessary to form an insulating film inside the laminated glass before use. Absent. A heat insulating film using a metal nitride instead of the silver screen has also been proposed (JP-A-63-2).
06333).

In recent years, AM and F have been used in automobiles and buildings.
Use of radio waves such as radio waves such as M, television waves such as VHF and UHF, mobile phones, and GPS systems utilizing artificial health is being promoted. Further, in order to transmit and receive this kind of radio wave, a method of forming a dedicated antenna on a window glass is generally used in automobiles. Further, as architectural glass, it is said that window glass affects the surrounding radio field strength in high-rise buildings.

On the other hand, when the above-mentioned conductive film is used as the heat insulating film, when a conductive film is formed on the antenna wire as disclosed in Japanese Patent Laid-Open No. 3-122032, a current flows between the antenna wires and the antenna. There was a drawback that the performance deteriorated. In addition to the drawback that the antenna performance deteriorates if the heat insulating film has good conductivity, there is a problem in radio wave transparency. From these viewpoints, a heat insulating film such as a drew de mirror type or a silver screen is not preferable.

Therefore, an object of the present invention is to solve the drawbacks related to radio waves and to provide a heat insulating film having excellent heat insulating performance and durability.

[0009]

SUMMARY OF THE INVENTION The above objects of the present invention are as follows.
On a glass substrate, tungsten and IVa group of the periodic table,
This is achieved by a heat insulating film characterized in that a complex oxide film comprising at least one element selected from the group consisting of IIIa group, VIIb group, VIb group and Vb group is formed. Hereinafter, the present invention will be described in more detail.

The Y value of the glass substrate is 1.0 to 1.0 on the chromaticity diagram.
It is preferable that the glass substrate has a hue of 1.4, an x value of 0.24 to 0.32, and a y value of 0.3 to 0.41.

It is known that the tungsten oxide film has strong absorption in the infrared region due to pentavalent tungsten, but does not absorb in the hexavalent state as described in WO ₃ . Tungsten oxide having absorption has an oxygen / tungsten ratio of 2.50 to 2.98. Infrared absorption cannot be expected at a ratio exceeding this range.

It is generally known that the tungsten oxide film has insufficient durability, although 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.

The composite oxide film essentially has the strong light absorption of 1 μm that tungsten oxide has. In addition, IVa group, IIIa group, VIIb group, VIb group and Vb of the periodic table
At least one element selected from the group consisting of the group is used to improve the durability which was not sufficiently obtained by the tungsten oxide alone and the conductivity which was difficult to control by the tungsten oxide alone. It exists in the oxide film.

Group IVa, Group IIIa, VII of the Periodic Table
At least one element selected from the group consisting of b-group, VIb-group and Vb-group coexists with tungsten oxide as a stable oxide in the composite 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 / □.

Si is a group IVa, Al is a group IIIa, Mn is a group VIIb, and C is a group VIb.
As the r and Vb groups, V or Nb can be preferably used. These elements are based on the fact that the alloy target for the composite oxide film is easily produced, and are not necessarily limited to the above elements.

The composite oxide film can be formed by the following sputtering method. Tungsten as a sputtering target and IVa group, IIIb group, VIIa of the periodic table
Using an alloy target containing a predetermined concentration of at least one element selected from the group consisting of Group VI, Group VIb and Group Vb, argon (Ar) and oxygen (O ₂ ) adjusted to have a predetermined gas ratio as a sputtering gas. ) A mixed oxide film can be formed on a glass substrate by a so-called reactive sputtering method using a mixed gas.

It is effective to form a transparent dielectric film on one or both sides of the tungsten-based composite oxide film by a sputtering method in order to improve the heat insulation performance by protecting the tungsten-based composite oxide film and the light interference effect. However, after all, the film that can be formed by the sputtering method is usually limited to a film thickness of 1 μm or less for industrial economy. Under severe usage conditions, it was necessary to further improve durability. In the present invention, a silicone hard coat film that can easily be made thicker to meet such requirements is used as the protective film. The silicone hard coat film is cured by a simple dehydration condensation reaction between silanols, and the cured film is a polymer substance having a siloxane bond as a skeleton. A thick film can be easily formed by so-called wet film formation such as dip coating, flow coating and spray coating.

However, when this silicone hard coat film was formed directly on the above-mentioned tungsten-based composite oxide film, there was no problem in optical performance such as heat insulation performance, but under severe conditions of use, There was a phenomenon that the silicone hard coat layer and the tungsten-based composite oxide film were separated. In order to solve this problem, that is, in order to improve the adhesiveness, it was found that an adhesive layer was provided between the two, and the durability could be improved.

[0019]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto.

Example 1 An example in which Si is selected as the IVb group will be described. As a glass substrate, the Y value is 1.27 and the x value is 0.
A glass substrate having a value of 29 and a y value of 0.32 was used. The glass substrate was degreased and washed with isopropyl alcohol, purely washed, and then nitrogen blow dried. This glass substrate was conveyed into the sputtering apparatus and exhausted to 5 × 10 ⁻⁶ Torr. As a sputtering target, W-
A 10 at% Si alloy target is installed.

First, in order to clean the target surface, argon gas was introduced into the vacuum layer as a sputtering gas so that the pressure in the vacuum layer was 5 × 10 ⁻³ Tor.
The flow rate of argon gas and the evacuation rate were adjusted so as to be r. Then, the target surface was cleaned with a sputtering power of 500 W for 3 minutes. Oxygen gas was introduced as the sputtering gas. At this time, the flow rate ratio of the argon gas and the oxygen gas was adjusted to 30: 4, and the pressure was 5 × 10 5.
^It was adjusted to be ^-3 Torr. After a time required for the gas concentration in the vacuum chamber to become uniform, film formation was started with a sputtering power of 500 W to obtain a composite oxide film having a film thickness of 90 nm.

The film resistance of the composite oxide film thus formed was about 40 MΩ / □, and there was no problem in radio wave transmission and antenna transmission / reception performance. In addition, FIG. 1 shows a light transmittance-wavelength spectrum of the tungsten oxide film when silicon is added. As for the spectral performance, as shown in FIG. 1, the transmittance was 70% in the visible light region, and the transmittance in the infrared region was about 22% at a wavelength of 1 μm, which was an excellent heat ray blocking property. This is in the visible light region (wavelength 0.38-0.
High transmittance at 78 μm) and in the infrared region (wavelength 0.7
8 to 2 μm), the transmittance is low. That is, the high transmittance in the visible region indicates good visibility, and the low transmittance in the infrared region indicates infrared rays (that is,
It shows that the heat rays are well blocked.

As for durability, 150 ° C., 10
Spectral performance did not change with time and had excellent durability. On the other hand, when this composite oxide film was analyzed by instrumental analysis, Si was present as a Si oxide and W was also an oxide. The ratio of W and oxygen is 2.7 to 2.9 with respect to W1.
And the ratio of W to Si is Si0.
It was 09, which almost reflected the target composition.

Example 2 An example in which Al is selected as the IIIb group will be described.
The glass substrate, the film forming procedure, and the film thickness were exactly the same as in Example 1, and a W-10 at% Al alloy target was used as the sputtering target. The film resistance of the composite oxide film thus formed was about 30 MΩ / □, and there was no problem in radio wave transmission and antenna transmission / reception performance. FIG. 2 shows a light transmittance-wavelength spectrum of the tungsten oxide film when aluminum is added. As for the spectral performance, as shown in FIG. 2, the transmittance was 70% in the visible light region, and the transmittance in the infrared region was about 21% at a wavelength of 1 μm, which was an excellent heat ray-shielding property. This is a high transmittance in the visible light region (wavelength 0.38 to 0.78 μm) as described in Example 1, and is high in the infrared region (wavelength 0.78 to 2 μm).
Indicates that the transmittance is low. That is, the high transmittance in this visible region shows good visibility,
The low transmittance in the infrared region indicates that the infrared rays (that is, heat rays) are well blocked.

Further, regarding durability, 150 ° C., 10
Spectral performance did not change with time and had excellent durability. On the other hand, when this composite oxide film was analyzed by instrumental analysis, Al was present as an Al oxide, and W was also an oxide. The ratio of W to oxygen is W1 to oxygen of 2.7 to 2.
9 and the ratio of W and Al is A with respect to W1.
It was 0.1 and reflected the target composition.

Example 3 An example in which Mn is selected as the VIIa group will be described.
The glass substrate, the film forming procedure, and the film thickness were exactly the same as in Example 1, and a W-10 at% Mn alloy target was used as the sputtering target. The film resistance of the composite oxide film thus formed was about 40 MΩ / □, and there was no problem in radio wave transmission and antenna transmission / reception performance. Further, the spectral performance was 70% or more in the visible light region, and the transmittance in the infrared region was about 25% at a wavelength of 1 μm, which was an excellent heat ray-shielding property.

Further, regarding durability, 150 ° C., 10
Spectral performance did not change with time and had excellent durability. On the other hand, when the composite oxide film was analyzed by instrumental analysis, Mn was present as Mn oxide, and W was also an oxide. The ratio of W to oxygen is 2.8 to 2.
9 and the ratio of W and Mn is M with respect to W1.
n 0.1, which reflected the target composition.

Example 4 An example in which Cr is selected as the VIa group will be described. The glass substrate, the film forming procedure, and the film thickness were exactly the same as in Example 1, and a W-10 at% Cr alloy target was used as the sputtering target. The film resistance of the composite oxide film thus formed was about 25 MΩ / □, and there was no problem in radio wave transmission and antenna transmission / reception performance. Further, the spectral performance was such that the transmittance was 60% or more in the visible light region, and the transmittance in the infrared region was about 16% at a wavelength of 1 μm, which was an excellent heat ray-shielding property.

Further, with respect to durability, 150 ° C., 10
Spectral performance did not change with time and had excellent durability. On the other hand, when this composite oxide film was analyzed by instrumental analysis, Cr was present as Cr oxide and W was also an oxide. The ratio of W to oxygen is 2.8 to 2.
9 and the ratio of W to Cr is C with respect to W1.
It was r0.08, which almost reflected the target composition.

Example 5 An example in which V is selected as the Va group will be described. The glass substrate, the film forming procedure and the film thickness are exactly the same as in Example 1,
A W-10 at% V alloy target was used as the sputter target. The film resistance of the composite oxide film thus formed was about 40 MΩ / □, and there was no problem in radio wave transmission and antenna transmission / reception performance. Further, the spectral performance was such that the transmittance was 70% or more in the visible light region, and the transmittance in the infrared region was about 27% at a wavelength of 1 μm, which was an excellent heat ray-shielding property.

Further, regarding durability, 150 ° C., 10
Spectral performance did not change with time and had excellent durability. On the other hand, when this composite oxide film was analyzed by instrumental analysis, V was present as V oxide and W was also oxide.
The ratio of W to oxygen is in the range of 2.8 to 2.9 with respect to W1, and the ratio of W to V is V 0.
It was 09, which almost reflected the target composition.

Example 6 An example in which Nb is selected as the Va group will be described. The glass substrate, the film forming procedure, and the film thickness were exactly the same as in Example 1, and a W-10 at% Nb alloy target was used as the sputtering target. The film resistance of the composite oxide film thus formed was about 40 MΩ / □, and there was no problem in radio wave transmission and antenna transmission / reception performance. In addition, the spectral performance was 70% or more in the visible light range, and the transmittance in the infrared range was about 29% at a wavelength of 1 μm, which was an excellent heat ray-shielding property.

Further, regarding durability, 150 ° C., 10
Spectral performance did not change with time and had excellent durability. On the other hand, when this composite oxide film was analyzed by instrumental analysis, Nb was present as an Nb oxide, and W was also an oxide. The ratio of W to oxygen is 2.8 to 2.
9 and the ratio of W and Nb is N with respect to W1.
b was 0.09, which almost reflected the target composition.

Example 7 An example in which Group IVa Si is selected as the tungsten-based composite oxide film and a SiO ₂ film is selected as the second layer will be described. As a glass substrate, Y value is 1.27 on the chromaticity diagram, x
A glass substrate having a value of 0.29 and ay value of 0.32 was used. The glass substrate was degreased and washed with isopropyl alcohol, purely washed, and then nitrogen blow dried. The glass was transferred to the substrate inside the sputtering equipment and transferred to 5 × 10 ^-6 Torr.
Exhausted to. In the sputtering device, W-5 at% was used as a sputtering target for the tungsten-based complex oxide film.
A Si alloy target and a Si target as a sputtering target for the second layer of SiO ₂ film are respectively installed.

In the film forming procedure, first, in order to clean the surface of the Si-W target, argon gas was introduced into the vacuum chamber as a sputtering gas, and the pressure in the vacuum chamber was 5 × 10 5.
^The argon gas flow rate and pumping speed were adjusted so as to be ⁻³ Torr. Next, the target surface was cleaned with a sputtering power of 500 w for 3 minutes. Next, oxygen gas was introduced into the sputtering gas. At this time, the flow rate ratio of the argon gas and the oxygen gas was adjusted to be 30: 4, and the pressure was 5
It was adjusted to be × 10 ⁻³ Torr. After the time required for the gas concentration in the vacuum chamber to become uniform, film formation was started with a sputtering power of 500 w, and the film thickness of the first layer was 4
A 0 nm Si tungsten oxide film was obtained.

Next, on the Si tungsten oxide film, the flow rate ratio of the argon gas and the oxygen gas was adjusted to 20:10 and the pressure was adjusted to 5 × 10 ⁻³ Torr.
After the time required for the gas concentration in the vacuum chamber to become uniform, a Si target was used and a sputtering power of 500 was used.
With w, a SiO ₂ film having a film thickness of 10 nm was obtained as the _second layer. Further, as a hard coat film, a Toshiba silicone hard coat film (trade name: Tosgard 520) is applied by a flow coating method, and then baked at 120 ° C. in the atmosphere for 1 hour.
It was deposited to a thickness of μm.

The heat-insulating glass thus produced has a transmittance of 70% or more in the visible light region, and a transmittance of about 25% at a wavelength of 1 μm in the infrared region, which is an excellent heat ray-shielding property. It was Regarding the durability, the spectral performance did not change under the environment of 50 ° C./95% RH, and the durability was excellent. The film resistance of the Si tungsten oxide film is about 40 MΩ.
It was / □, and there was no problem in radio wave transmission and antenna transmission / reception performance.

Example 8 A Si tungsten oxide film was used as in Example 1 as the tungsten oxide type composite oxide film, and Ti was used as the second layer.
An example in which O ₂ is selected will be described. The glass substrate and the film formation procedure and film thickness of the Si tungsten oxide film are exactly the same as those in the first embodiment. The TiO ₂ film used as the _second layer uses a Ti target and uses a mixed gas of Ar gas and O ₂ gas (A
A film was formed by reactive sputtering using r: O ₂ = 20: 5) to form a TiO ₂ film with a thickness of 5 nm. Further, a hard coat film having a thickness of 1 μm was formed in exactly the same manner as in Example 1.

The heat-insulating glass produced in this manner has a spectroscopic performance of 70% or more in the visible light range, and has an excellent heat ray-shielding property of about 22% in the infrared range at a wavelength of 1 μm. Had. Also regarding durability, 50
There was no change in the spectral performance under the environment of ℃ and 95% RH, and it had excellent durability.

Example 9 A Si tungsten oxide film was used as in Example 1 as the tungsten oxide type composite oxide film, and Zr was used as the second layer.
An example in which O ₂ is selected will be described. The glass substrate and the film formation procedure and film thickness of the Si tungsten oxide film are exactly the same as those in the first embodiment. The ZrO ₂ film used as the _second layer uses a Zr target and uses a mixed gas of Ar gas and O ₂ gas (A
A film was formed by reactive sputtering using r: O ₂ = 20: 5) to form a ZrO ₂ film with a thickness of 5 nm. Further, a hard coat film having a thickness of 1 μm was formed in exactly the same manner as in Example 1.

The heat-insulating glass produced in this manner has a spectral performance of 70% or more in the visible light range, and has an excellent heat ray blocking property of about 23% in the infrared range at a wavelength of 1 μm. Had. Also regarding durability, 50
There was no change in the spectral performance under the environment of ℃ and 95% RH, and it had excellent durability.

Example 10 Same as Example 1 as a tungsten oxide type composite oxide film
Si tungsten oxide film is used for
An example of selecting a chromium film will be described. Glass substrate, tan
The film forming procedure and film thickness of the gustene-based composite oxide are the same as those in Example 1.
Exactly the same. Chromium oxide film used as the second layer
Uses a Cr target and Ar gas and O ₂Mixing with gas
Gas (Ar: O₂= 15: 15) reactive spa
A CrO film was formed to a thickness of 5 nm. More real
The hard coat film was formed to 1 μm in exactly the same manner as in Example 1.
did.

The heat-insulating glass thus produced has a spectral performance of 70% or more in the visible light range, and has an excellent heat ray-shielding property of about 24% in the infrared range at a wavelength of 1 μm. Was. As for durability, 50 ° C, 9
There was no change in spectral performance under a 5% RH environment, and it had excellent durability.

Example 11 A Si tungsten oxide film was used as in Example 1 as the tungsten oxide type composite oxide film, and Si was used as the second layer.
An example of selecting a composite oxide film of Ti and Ti will be described. The procedure for forming the film and the film thickness of the glass substrate and the tungsten-based composite oxide are exactly the same as in Example 1. The SiTi composite oxide film used as the second layer uses a Si-20 at% Ti alloy target and uses a mixed gas (A) of Ar gas and O ₂ gas.
A film was formed by reactive sputtering using r: O ₂ = 20: 10) to form a SiTiO film with a thickness of 10 nm. Further, a hard coat film having a thickness of 1 μm was formed in exactly the same manner as in Example 1.

The heat-insulating glass thus produced has a spectral transmittance of 70% or more in the visible light region, and an excellent heat ray-shielding property of about 24% in the infrared region at a wavelength of 1 μm. Had. Also regarding durability, 50
There was no change in the spectral performance under the environment of ℃ and 95% RH, and it had excellent durability.

Example 12 A structure in which a dielectric layer is provided between a tungsten oxide type composite oxide film and a glass substrate will be described. A SiO ₂ film is formed as a first layer on a glass substrate, a Si tungsten oxide composite oxide layer is formed as a _second layer, and a SiO ₂ film is formed as a third layer by sputtering, and finally a fourth layer is formed. As a result, a hard coat film was sequentially formed. The film forming method is exactly the same as that of the first embodiment, and the film thickness is 30 n for the first layer SiO ₂ film.
m, a second layer of Si-added tungsten oxide film of 90 n
m, the third layer SiO ₂ film was formed to a thickness of 10 nm, and the fourth hard coat film was formed to a thickness of 1 μm.

The heat-insulating glass thus produced has a spectral dispersibility of 70% or more in the visible light range and a transmittance in the infrared range of about 20% at a wavelength of 1 μm, which is an excellent heat ray-shielding property. Had. Also regarding durability, 50
There was no change in the spectral performance under the environment of ℃ and 95% RH, and it had excellent durability.

Comparative Example 1 A case where the Si concentration in the composite oxide film is different from that in Example 1 will be described. W-1 as sputter target
W-2 at% Si instead of 0 at% Si alloy target
A complex oxide film was formed in exactly the same manner as in Example 1 except that the alloy target and the W-20 at% Si alloy target were used. When the W-2 at% Si alloy target is used, the formed composite oxide film has a film resistance value of 90.
It was 0 KΩ / □, and there was no problem in radio wave transparency and antenna transmission / reception performance.

As for the spectral performance, the transmittance in the infrared region has a wavelength of 1 μm.
Although it had an excellent heat ray-shielding property of about 19% in m, the transmittance was 68% in the visible light region, and the light transmittance of visible light was poor. Further, the durability was increased by about 5% at 150 ° C. for 10 hours. On the other hand, when this composite oxide film was analyzed by instrumental analysis, Si was present as a Si oxide and W was also an oxide. The ratio of W and oxygen was in the range of 2.7 to 2.9 with respect to W1, and the ratio of W and Si was Si 0.02 with respect to W1, reflecting the target composition.

When the W-20 at% Si alloy target is used, the formed composite oxide film has a film resistance value of 6
It was 0 MΩ / □, and there was no problem in radio wave transparency and antenna transmission / reception performance. Regarding the spectral performance, the transmittance was 70% in the visible light range, and the visible light transmittance was sufficient, but the transmittance in the infrared region was about 40% at a wavelength of 1 μm, and the heat ray blocking property was poor.

The durability did not change in spectral characteristics at 150 ° C. for 10 hours. When this composite oxide film was analyzed by instrumental analysis, Si was present as a Si oxide and W was also an oxide. The ratio of W and oxygen is in the range of 2.8 to 2.9 with respect to W1, and the ratio of W and Si is W.
Si was 0.18 for 1 and almost reflected the target composition.

From the results of these two examples, Si in the composite oxide was
It can be seen that when the concentration is higher than the predetermined concentration, the heat ray blocking property is deteriorated, and when the concentration is lower than the predetermined concentration, the light transmittance in the visible light region is deteriorated and the durability is insufficient.

Comparative Example 2 A case where the ratio of W and oxygen in the composite oxide film is different from that of Example 1 will be described. A composite oxide film was formed in exactly the same manner as in Example 1 except that the mixing ratio of the argon gas and the oxygen gas of the sputtering gas was changed as the film forming procedure. The case where the film is formed by adjusting the flow rate ratio of the argon gas and the oxygen gas to 30: 1 will be described. The film resistance of the composite oxide film thus formed was about 100 KΩ / □, and the radio wave transparency and the antenna transmission / reception performance deteriorated.

Further, the spectral performance has a transmittance of 3 in the visible light region.
0%, and the transmittance in the infrared region is about 18 at a wavelength of 1 μm.
% And had an excellent heat ray shielding property. Furthermore, durability is 1
The transmittance increased by about 10% at 50 ° C. for 10 hours. on the other hand,
When this composite oxide film was analyzed by instrumental analysis, Si was present as a Si oxide and W was also an oxide. The ratio of W and oxygen was in the range of 2.4 to 2.5 for W1 with respect to W1, and the ratio of W and Si was 0.09 for W1, which almost reflected the target composition.

The flow rate ratio of argon gas and oxygen gas is 30:
The case of adjusting the film thickness to 6 and forming the film will be described. The film resistance of the composite oxide film thus formed is about 1200 MΩ /
□, and there was no problem in radio wave transmission and antenna transmission / reception performance. In addition, the spectral performance has a transmittance of 8 in the visible light range.
It was 0% and had a sufficient light transmittance, but the transmittance in the infrared region was about 35% at a wavelength of 1 μm and the heat ray blocking property was poor.

Further, regarding durability, 150 ° C., 10
Spectral performance did not change with time and had excellent durability. On the other hand, when this composite oxide film was analyzed by instrumental analysis, Si was present as a Si oxide and W was also an oxide. The ratio of W to oxygen is 2.95 to oxygen for W1.
It was in the range of 3.0, and the ratio of W and Si was Si 0.09 with respect to W1, which almost reflected the target composition.

From the results of these two examples, when the ratio of W and oxygen in the composite oxide is more than a predetermined value, the heat ray blocking property is deteriorated, and when it is less than the predetermined ratio, the light transmittance in the visible light region is obtained. Deteriorates and the durability becomes insufficient.

Comparative Example 3 A case where the thickness of the composite oxide film is different from that of Example 1 will be described. Other than adjusting the film formation time and changing the film thickness,
A composite oxide film was formed by the same method as in Example 1. When the film thickness of the composite oxide film was 20 nm, the film resistance of the formed composite oxide film was 80 MΩ / □, and there was no problem in radio wave transmission and antenna transmission / reception performance. Regarding the spectral performance, the transmittance was 75% in the visible light range, and the light transmittance of the visible light was sufficient, but the transmittance in the infrared range was about 33% at a wavelength of 1 μm, and the heat ray blocking property was poor. .

The durability did not change in spectral performance at 150 ° C. for 10 hours. On the other hand, when this composite oxide film was analyzed by instrumental analysis, Si was present as a Si oxide and W was also an oxide. The ratio of W and oxygen was in the range of 2.8 to 2.9 with respect to W1, and the ratio of W and Si was Si 0.09 with respect to W1, reflecting the target composition.

When the film thickness of the composite oxide film is 500 nm, the film resistance value of the formed composite oxide film is 10 MΩ / □.
Therefore, there was no problem in radio wave transparency and antenna transmission / reception performance. Regarding the spectral performance, the transmittance was 65% in the visible light region, and the light transmittance of visible light was poor. The transmittance in the infrared region was about 17% at a wavelength of 1 μm, and the heat ray blocking property was excellent. Moreover, the durability did not change in the spectral performance at 150 ° C. for 10 hours.

On the other hand, when this composite oxide film was analyzed by instrumental analysis, Si was present as a Si oxide and W was also an oxide. The ratio of W to oxygen is 2.
It was in the range of 8 to 2.9, and the ratio of W to Si was Si 0.09 with respect to W1, reflecting the target composition.

Comparative Example 4 The case where silver (Ag) is added as a group Ib will be described. A composite oxide film was formed in exactly the same manner as in Example 1 except that a W-10 at% Ag alloy target was used as the sputtering target. The obtained composite oxide film had no problem with a film resistance value of 8 MΩ / □, but had a low light transmittance of about 30% in the visible light region, which limited its application as a window glass material. Oops.

Comparative Example 5 A case where tellurium (Te) is added as a VIb group will be described. W-10at% T as sputter target
A complex oxide film was formed in exactly the same manner as in Example 1 except that the e-alloy target was used. The obtained composite oxide film had no problem with a film resistance value of 800 KΩ / □, but had a low light transmittance of about 50% in the visible light region, which limited its application as a window glass material. It was As for durability, the transmittance is about 10% at 150 ° C for 10 hours.
It rose and was not enough in terms of durability.

Comparative Example 6 A case will be described in which nickel is used instead of IVb group silicon (Si) and tungsten as an additional element. A composite oxide film was formed in exactly the same manner as in Example 1 except that a Ni-10 at% Si alloy target was used as the sputtering target. The obtained composite oxide film had no problem with a film resistance value of 15 MΩ / □, but the light transmittance in the visible light region was low at about 65%, and the light transmittance in the infrared region was about 45%. And the heat ray blocking property was getting worse.

[0065]

According to the heat insulating film of the present invention, it is possible to obtain a glass which is durable, has a high light transmittance in the visible light region, and has a low light transmittance in the infrared region, and which has an excellent heat insulating effect. Further, by laminating the silicone hard coat film on the outermost layer, the durability can be further improved.

[Brief description of drawings]

FIG. 1 shows a light transmittance-wavelength spectrum of a tungsten oxide film when silicon is added in Example 1.

FIG. 2 shows a light transmittance-wavelength spectrum of a tungsten oxide film when aluminum is added in Example 2.

FIG. 3 is a cross-sectional view showing the configuration of Example 7.

FIG. 4 is a cross-sectional view showing the structure of a twelfth embodiment.

Claims (11)

[Claims] 1. A composite oxide film comprising tungsten and at least one element selected from the group consisting of IVa group, IIIa group, VIIb group, VIb group and Vb group of the periodic table on a glass substrate. A heat insulating film characterized by being formed. 2. The complex oxide film is group IVa or I of the periodic table.
The heat insulating film according to claim 1, which contains at least one element selected from the group consisting of IIa group, VIIb group, VIb group, and Vb group in a range of 3 to 15 atom%. 3. The heat insulating film according to claim 1, wherein the composite oxide film has an oxygen / tungsten ratio of tungsten oxide in the range of 2.50 to 2.98. 4. The film resistance value of the composite oxide film is 500 KΩ /
The heat insulating film according to claim 1, which is in the range of □ to 800 MΩ / □. 5. The glass substrate has a Y value of 1.00 on the chromaticity diagram.
~ 1.40 range, x value is 0.24 to 0.32 range,
The heat insulating film according to claim 1, wherein the y value has a hue of 0.30 to 0.41. 6. The heat insulating film according to claim 1, wherein the composite oxide film is formed by a sputtering method. 7. A composite oxide film having a thickness of 50 to 200 nm.
The heat insulating film according to claim 1, wherein 8. The heat insulation according to claim 1, wherein a transparent dielectric film is provided as a third layer on the complex oxide film, and a silicone hard coat film is laminated as a fourth layer on the three layers. Glass. 9. The transparent dielectric film is made of at least one selected from the group consisting of oxides of silicon, titanium, chromium and zirconium, and has a film thickness in the range of 5 to 100 nm. Item 1. The heat insulating glass according to item 1. 10. The heat insulating glass according to claim 1, wherein the film thickness of the silicone hard coat film is in the range of 0.5 to 10 μm. 11. Between the glass substrate and the composite oxide film,
The heat insulating glass according to claim 8, further comprising a transparent dielectric film.