JPH11263639A - Coating liquid for formation of heat ray shielding film, and heat ray shielding film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat ray shielding film having high transmittance and low reflectance for light in a visible ray region and low transmittance and high reflectance for light in a near infrared region, in which the conductivity of the film can be controlled almost to >10<6> Ω/sq., and to provide a coating liquid which can be easily applied to form the film above described. SOLUTION: The coating liquid for a heat ray shielding film has dispersion of at least one kind of titanium nitride fine particles, zirconium nitride fine particles, hafnium nitride fine particles, vanadium nitride fine particles, niobium nitride fine particles and tantalum nitride fine particles having <100 nm average particle size. Further, the coating liquid contains at least one kind of ruthenium oxide fine particles and iridium oxide fine particles having <=100 nm average particle size. The heat ray shielding film is obtd. by applying the coating liquid above described on a base body and heating.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transparent or transparent glass or plastics or any other heat ray shielding function, such as a window for a vehicle, a building, an office or a general house, a telephone box, a show window, a lighting lamp and the like. The present invention relates to a coating liquid for applying to a translucent substrate to form a heat ray shielding film, and a heat ray shielding film obtained by the application liquid.

[0002]

2. Description of the Related Art Conventionally, as a method of removing or reducing a heat component from an external light source such as sunlight or a light bulb, a heat ray reflecting glass using a material which reflects a visible / infrared wavelength on a glass surface is used. Was being done. As a material for heat ray reflection, a metal oxide such as FeO _x , CoO _x , CrO _x , or TiO _x or a metal material having a large amount of free electrons such as Ag, Au, Cu, Ni, or Al is selected. It has been.

However, these materials have the property of simultaneously reflecting or absorbing light in the visible light region in addition to near infrared rays which greatly contribute to the thermal effect, and have a drawback that the visible light transmittance is reduced. Transparent base materials used for building materials, vehicles, telephone boxes, etc., require high transmittance in the visible light region, and when using these materials, the thickness must be extremely thin to increase the visible light transmittance. Must be
Therefore, it has been common practice to form a very thin film having a thickness of 10 nm by using a physical film forming method such as spray baking, a CVD method, or a sputtering method or a vacuum evaporation method.

[0004] These film forming methods require large-scale equipment and vacuum equipment, have problems in productivity and enlargement of the area, and have a high film manufacturing cost.

[0005] In these films, when the film thickness is reduced and the transmittance is increased, the heat ray shielding characteristics are degraded. Conversely, when the film thickness is increased and the heat ray shielding characteristics are increased, the films become dark.
Further, these materials tend to have a high reflectance in the visible light region at the same time when trying to enhance the heat ray shielding properties, giving a glare-like appearance like a mirror and impairing the aesthetic appearance.

In addition, many of these materials have high conductivity of the film, and if the conductivity of the film is high, a cellular phone or a T
V, radio and other radio waves are reflected and become unreceivable,
There were drawbacks such as causing radio interference in the surrounding area.

[0007] In order to improve the above-mentioned drawbacks, the physical properties of the film are such that the reflectance of light in the visible light region is low, the reflectance of light in the near infrared region is high, and the conductivity of the film is low. Generally 1
0 ⁶ Ω / □ has been necessary to form a controllable membrane above. However, conventionally, such a film or a material for forming such a film has not been known.

As a material having a high visible light transmittance and a heat ray shielding function, antimony-containing tin oxide (ATO)
Also, tin-containing indium oxide (ITO) is known.
Although these materials have a relatively low visible light reflectance and do not give a glare-like appearance, the plasma wavelength is relatively long in the near infrared region, and these films have a near-infrared region close to visible light. The reflection and absorption effects were not sufficient. Further, when these films are formed by a physical film forming method, there is a disadvantage that the conductivity of the films is increased and radio waves are reflected.

[0009]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned conventional problems and has a high transmittance of light in the visible light region and a low reflectance, and a low transmittance of light in the near infrared region and a low reflectance. A coating solution that can form a film having a high rate and a film conductivity of approximately 10 ⁶ Ω / □ or more by a simple coating method without using a high-cost physical film forming method; An object is to provide a heat ray shielding film.

[0010]

Means for Solving the Problems In order to achieve the above object, the present inventors have focused on a nitride having a large amount of free electrons as a characteristic of the material itself, and as a result of various studies, have found that the And obtain a highly dispersed film to have a maximum transmittance in the visible light region and a strong plasma reflection in the near infrared region near the visible light region to minimize the transmittance. The present invention was completed, and the present invention was completed.

That is, the coating liquid for a heat ray shielding film of the present invention comprises titanium nitride fine particles having an average particle diameter of 100 nm or less, zirconium nitride fine particles having an average particle diameter of 100 nm or less, hafnium nitride fine particles having an average particle diameter of 100 nm or less, and an average particle diameter of 1 nm.
Vanadium nitride fine particles of not more than 00 nm, average particle diameter 100
nm or less niobium nitride fine particles and an average particle diameter of 100
At least one of tantalum nitride fine particles having a diameter of not more than nm is dispersed.

Further, another coating solution for forming a heat ray shielding film of the present invention comprises titanium nitride fine particles having an average particle diameter of 100 nm or less, zirconium nitride fine particles having an average particle diameter of 100 nm or less, hafnium nitride fine particles having an average particle diameter of 100 nm or less, and Vanadium nitride fine particles having a particle size of 100 nm or less, average particle size of 10
Niobium nitride fine particles of 0 nm or less and an average particle size of 10
At least one of tantalum nitride fine particles having a diameter of 0 nm or less, and ruthenium oxide fine particles having an average particle diameter of 100 nm or less;
Further, it is characterized by containing at least one kind of iridium oxide fine particles having an average particle diameter of 100 nm or less.

[0013] In another aspect of the present invention, the coating solution for forming a heat ray shielding film further comprises a metal alkoxide of silicon, zirconium, titanium or aluminum or a partially hydrolyzed polymer of metal alkoxide. Characterized in that at least one of them is contained.

The coating solution for forming a heat ray shielding film having any one of the above constitutions may contain a resin binder.

Further, the heat ray shielding film of the present invention is a fine particle dispersion film obtained by applying any one of the above-mentioned coating solutions for forming a heat ray shielding film to a substrate and then heating the substrate. , Titanium nitride, zirconium nitride, hafnium nitride,
Vanadium nitride, niobium nitride, tantalum nitride, ruthenium oxide, and at least one kind of fine particles of iridium oxide, the fine particle component is a resin binder,
Alternatively, it is characterized by being dispersed in an oxide binder containing at least one of metal oxides of silicon, zirconium, titanium, and aluminum.

Further, the heat ray shielding film is further coated with an oxide film containing at least one of metal oxides of silicon, zirconium, titanium, and aluminum. A resin film may be further coated on the shielding film to form a multilayer heat ray shielding film.

Any one of the above heat ray shielding films has a transmittance of
A maximum value at a wavelength of 400 to 700 nm and a wavelength of 700 to 18
It has a characteristic that it has a minimum value at 00 nm and the difference between the maximum value and the minimum value is 15 points or more in percentage, and the surface resistance value is 10 ⁶ Ω / □ or more. And

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Nitride fine particles used in the present invention include titanium nitride (TiN), zirconium nitride (ZrN), hafnium nitride (HfN), vanadium nitride (VN), niobium nitride (NbN), and nitrided nitride. Tantalum (T
aN) and the like. Further, the nitride fine particles used in the present invention may be partially or entirely replaced with oxynitride. It is preferable that the surface of these nitride fine particles is not oxidized, but usually the surface is often slightly oxidized, and it is inevitable to some extent that the surface is oxidized in the fine particle dispersion step. However, even in that case, there is no change in the effectiveness of exhibiting the heat ray shielding effect. In addition, these nitride fine particles can obtain a larger heat ray shielding effect as the perfection as a crystal is higher, but even if the crystallinity is low and an X-ray diffraction causes an extremely broad diffraction peak,
If the basic bond inside the fine particles is composed of the bond between each metal and nitrogen, a heat ray shielding effect is exhibited.

The fine particles of ruthenium oxide or iridium oxide used in the present invention include ruthenium dioxide (RuO ₂ ) and lead ruthenate (Pb ₂ Ru).
₂ O _6.5 ), bismuth ruthenate (Bi ₂ Ru ₂ O ₇ ),
Iridium dioxide (IrO ₂ ), bismuth iridate (Bi ₂ Ir ₂ O ₇ ), lead iridate (Pb ₂ Ir)
_Fine particles such as ₂ O _6.5 ) are typical examples. These fine particles are stable as oxides, retain a large amount of free electrons, and have an extremely effective heat ray shielding function.

These nitride fine particles, ruthenium oxide fine particles, and iridium oxide fine particles are powders colored in gray black, brown black, green black or the like. In the dispersed state, the film has visible light transmittance. However, the infrared light shielding ability can be maintained sufficiently strong. Although the reason for this is not understood in detail, the amount of free electrons in these fine particles is large, and the plasma frequency due to free electron plasmons inside and on the fine particles is just in the vicinity of the visible to near-infrared. It is considered that heat rays in the wavelength region are selectively reflected and absorbed.
According to the experiment, the transmittance of a film in which these fine particles are sufficiently fine and uniformly dispersed has a wavelength of 400 to 700 nm.
At the wavelength of 700 to 1800 nm, and the difference between the maximum value and the minimum value of the transmittance is 15 points or more as a percentage. Visible light wavelength is 380-780 nm, visibility is 550 nm
Considering that the film has a bell shape with a peak in the vicinity, it can be understood that such a film effectively transmits visible light and effectively reflects and absorbs other heat rays.

In the present invention, the average particle diameter of the nitride fine particles, ruthenium oxide fine particles, and iridium oxide fine particles in the coating solution is preferably 100 nm or less. Particle size 100
When it is larger than nm, the specific transmittance profile as described above, that is, the transmittance is 400 to 700 wavelengths
nm with a maximum value and a wavelength of 700 to 1800 nm
Further, a profile in which the difference between the maximum value and the minimum value is 15 points or more in percentage cannot be obtained, and a grayish film having a monotonously reduced transmittance is obtained. If the particle diameter is larger than 100 nm, the tendency of the fine particles in the dispersion liquid to agglomerate becomes strong, which causes sedimentation of the fine particles. Fine particles having a size of 100 nm or more or their aggregated coarse particles serve as a light scattering source and cause clouding (haze) on the film.
Or the visible light transmittance is reduced. Therefore, the average particle size of the inorganic fine particles needs to be 100 nm or less. The lowest economically available particle size is 2
Although it is about nm, the lower limit is not limited to this.

The dispersion medium of the fine particles in the coating liquid is not particularly limited, and can be selected according to the coating conditions and coating environment, the alkoxide in the coating liquid, the synthetic resin binder, and the like. Various organic solvents such as ethers, ethers, esters and ketones can be used. Further, if necessary, acid or alkali may be added to adjust the pH. Further, in order to further improve the dispersion stability of the fine particles in the coating liquid, it is possible to add various surfactants, coupling agents and the like. The amount of each addition at that time is 30% by weight or less, preferably 5% by weight or less based on the inorganic fine particles.

When the film is formed by using this coating solution, the conductivity of the film is formed along the conductive path passing through the contact portion of the fine particles. Therefore, for example, the amount of the surfactant or the coupling agent may be adjusted. , The conductive path can be partially cut, and the conductivity of the film can be easily reduced to a surface resistance value of 10 ⁶ Ω / □ or more. The conductivity can also be controlled by adjusting the content of a metal alkoxide of silicon, zirconium, titanium, or aluminum, or a partially hydrolyzed polymer of these metals, or a synthetic resin binder.

The method for dispersing the fine particles can be arbitrarily selected as long as the fine particles are uniformly dispersed in the solution. Examples of the method include a bead mill, a ball mill, a sand mill, and an ultrasonic dispersion method. .

The heat ray shielding film in the present invention is a film in which the fine particles are deposited at high density on a substrate to form a film, and a metal alkoxide of silicon, zirconium, titanium, or aluminum contained in a coating solution or The metal partially hydrolyzed polymer or synthetic resin binder is applied,
After curing, there is an effect of improving the binding property of the fine particles to the base material and further improving the hardness of the film. Further, a film containing a metal alkoxide such as silicon, zirconium, titanium, and aluminum, a hydrolyzed polymer of these metal alkoxides, or a synthetic resin is further coated as a second layer on the film thus obtained. Thus, it becomes possible to further improve the binding force of the film containing fine particles as a main component to the substrate, and the hardness and weather resistance of the film.

Silicon, zirconium, titanium,
When a metal alkoxide of aluminum, or a hydrolyzed polymer of these metals, or a synthetic resin binder is not contained, a film obtained after applying this coating solution to a substrate has a film structure in which only the fine particles are deposited on the substrate. Become. Although it shows a heat ray shielding effect as it is, this film has the same
Further, silicon, zirconium, titanium, metal alkoxide of aluminum, or hydrolyzed polymer of these metals,
Alternatively, a coating liquid containing a synthetic resin binder is applied to form a coating to form a multilayer film, so that the coating liquid component
Since the film is formed so as to fill the gap where the fine particles of the layer are deposited, the haze of the film is reduced, the visible light transmittance is improved, and the binding property of the fine particles to the base material is improved.

As a method of binding a film containing the above fine particles as a main component with a metal alkoxide of silicon, zirconium, titanium, or aluminum, or a film made of a hydrolyzed polymer of these metals, a sputtering method or a vapor deposition method is used. A coating method is also possible, but a coating method is effective because of advantages such as easy film formation process and low cost. This coating solution for coating is
It contains at least one metal alkoxide of silicon, zirconium, titanium, or aluminum in water or alcohol, or a hydrolyzed polymer of these metals, and contains a total solution in terms of oxides obtained after heating. 4 in
It is preferably 0% by weight or less. If necessary, the pH can be adjusted by adding an acid or an alkali. By coating such a liquid as a second layer on a film containing the above fine particles as a main component and heating, an oxide film of silicon, zirconium, titanium, aluminum or the like can be easily formed.

The method of applying the coating liquid and the coating liquid for forming a coating is not particularly limited, and the processing liquid may be applied by spin coating, spray coating, dip coating, screen printing, roll coating, flow coating, or the like. Any method can be appropriately adopted as long as it can be applied flat and thinly and uniformly.

The substrate heating temperature after application of the coating solution containing the metal alkoxide and its hydrolyzed polymer is 100 ° C.
If it is less than 1, the polymerization reaction of the alkoxide or its hydrolyzed polymer contained in the coating film often remains uncompleted, and water or an organic solvent remains in the film, reducing the visible light transmittance of the film after heating. 100 ° C. or higher is preferable,
More preferably, heating can be performed at a temperature equal to or higher than the boiling point of the solvent in the coating solution.

When a synthetic resin binder is used, it may be cured according to the respective curing method. For example, an ultraviolet curable resin may be appropriately irradiated with ultraviolet light, and a room temperature curable resin may be left as it is after application. Since it is sufficient to apply it, it can be applied to an existing window glass or the like on site, and the versatility is expanded.

An organosilazane solution may be used as a binder component used in the coating solution of the present invention or as a coating solution for overcoating. As organosizaran solutions, those having a polymerization curing temperature of 100 ° C. or lower due to modification of a side chain group or addition of an oxidation catalyst are commercially available, and by using these, the film forming temperature can be considerably lowered. As the room temperature curable binder, a commercially available silicate-based binder can be used. Both are cured after SiO
Forming an inorganic film of No. ₂ , it is superior to a resin film in weather resistance and film strength.

Since the film of the present invention is a film in which the ultrafine particles are dispersed, a film having a mirror-like surface in which crystals are densely filled like a thin film of an oxide produced by a physical film-forming method. The reflection in the visible light region is less than that of the above, and it is possible to avoid giving a glare-like appearance. On the other hand, as described above, due to having a plasma frequency in the visible to near-infrared region, the accompanying plasma reflection increases in the near-infrared region,
It has very favorable characteristics. When it is desired to further suppress the reflection in the visible light region, a film having a low refractive index such as SiO ₂ or MgF can be easily formed on the fine particle dispersion film to have a luminous reflectance of 1% or less. Multilayer films can be manufactured.

In order to improve the transmittance, the coating solution of the present invention may further contain ultrafine particles such as ATO, ITO, and aluminum-added zinc oxide. As the amount of these transparent ultrafine particles increases, the absorption in the near infrared region close to visible light increases, so that a heat ray shielding film having high visible light transmittance can be obtained. Conversely, it is also possible to add the coating solution of the present invention to a solution in which ultrafine particles such as ATO, ITO, and aluminum-added zinc oxide are dispersed, to color the film and at the same time assist its heat ray shielding effect. In this case, since the heat ray shielding effect can be assisted with a very small addition amount to ITO or the like as a main component, the required amount of ITO can be greatly reduced, and there is an advantage that the cost of the liquid can be reduced.

The coating solution of the present invention contains inorganic titanium oxide, zinc oxide, and titanium oxide in order to improve the function of shielding ultraviolet rays harmful to the human body at the same time as the ability to shield infrared rays when the coating solution is formed. Fine particles such as cerium and one or more of organic benzophenone and benzotriazole may be added.

The coating liquid according to the present invention is a liquid in which the above-mentioned inorganic fine particles are dispersed, and does not form a desired heat ray shielding film by utilizing decomposition or chemical reaction of coating components due to heat during firing. It is possible to form a permeable film having stable characteristics and a uniform film thickness.

The fine particle-dispersed film of the present invention is a film in which fine particles are deposited at a high density on a substrate to form a film, and a metal alkoxide of silicon, zirconium, titanium, or aluminum contained in a coating solution or The hydrolyzed polymer of (1) or the synthetic resin binder has an effect of improving the binding property of the fine particles to the substrate after the coating film is cured, and further improving the strength of the film.

As described above, according to the present invention, it is possible to produce a film having a heat ray shielding effect by appropriately mixing the above-mentioned inorganic fine particle materials. Weather resistance is very high compared to materials,
For example, even if it is used in the area where sunlight (ultraviolet rays) hits,
Deterioration of color and functions hardly occurs.

[0038]

EXAMPLES Examples of the present invention will be described below together with comparative examples.

Example 1 TiN having an average particle size of 40 nm
8 g of fine particles, 80 g of diacetone alcohol (DAA),
An appropriate amount of water and a dispersant were mixed, and the mixture was ball-milled using zirconia balls having a diameter of 4 mm for 100 hours to prepare 100 g of a TiN dispersion. This is designated as solution A. Next, 6 g of ethyl silicate 40 (manufactured by Tama Chemical Industry Co., Ltd.) having an average degree of polymerization of 4 to pentamer, 31 g of ethanol, 8 g of 5% hydrochloric acid aqueous solution, 50 g of an ethyl silicate solution prepared with 5 g of water, 800 g of water, and 300 g of ethanol was mixed and stirred well to prepare 1150 g of a mixed solution of ethyl silicate. This is designated as solution B.

The solution A and the solution B were mixed at a TiN concentration of 1.0%,
Mix at a ratio such that the TiN / SiO ₂ ratio is 4: 1.
The mixture was stirred to prepare a coating solution. This is designated as liquid C. This C
200 g x 200 x rotating 15 g of liquid at 145 rpm
The solution was dropped on a 3 mm soda lime glass substrate from a beaker, shaken for 3 minutes, and then stopped rotating. This was placed in an electric furnace at 180 ° C. and heated for 30 minutes to obtain a target film.

The spectral characteristics of the formed film were measured using a spectrophotometer manufactured by Hitachi, Ltd. 1 and 2 show the transmission profile and the reflection profile of the film of this example using TiN fine particles. The maximum value of the transmittance is 425 nm,
The minimum value is 745 nm, the maximum value of the reflectance is around 1000 nm, and the difference between the maximum value and the minimum value of the transmittance is 22% in percentage.
At a certain point, the profile is such that the transmittance is high at the wavelength of visible light and the transmittance is low at the wavelength of near infrared.
Based on R-3106, a visible light transmittance of 44% and a solar radiation transmittance of 42% were obtained.

The glass with the film was 100 × 100 × 60
It was set on the upper surface of a small box-shaped box made of vinyl chloride of 1 mm and left for 1 hour under sunlight on a sunny day, and the temperature change in the box was measured. When the glass with the film was arranged, the temperature became constant at 45 ° C., but when a commercially available heat ray absorbing bronze glass (visible light transmittance: 64%) was arranged, the temperature became 55 ° C.
When transparent clear glass is placed, it will be 61 ° C,
A clear shielding effect of heat rays due to solar radiation was observed. As described above, the film according to the present embodiment in which the visible light has the transmittance maximum, the near infrared has the transmittance minimum, and the near infrared has the reflectance maximum, the excellent heat ray shielding effect is obtained. It was confirmed that it had.

The transmission color of the film according to this example was a beautiful deep blue. In addition, while the solar reflectance was as high as 18%, the visible light reflectance was as low as 12%, and the film surface did not feel as glaring as a commercially available heat ray reflective glass.

Further, when the surface resistance of this film was measured using a surface resistance meter manufactured by Mitsubishi Chemical Corporation, it was found to be 8 × 10 ⁸ Ω / □. I found that there was no problem.

Comparative Example 1 A commercially available heat-reflective bronze glass produced by a physical film forming method, which is more expensive than the coating method, was measured for its spectral transmittance at 340 to 1800 nm and was visible according to JIS-R-3106. When the light transmittance and the solar transmittance were determined, they were 45% and 51%, respectively, and the solar transmittance was slightly higher than that of the film of Example 1 described above. The solar reflectance is a good value of 23%,
The visible light reflectance was as high as 30%, and the appearance was a mirror-like appearance. Further, the surface resistance of the film surface is as low as 83 Ω / □, and it is clear that there is a problem in radio wave transmission and reflection.

Example 2 After spin coating the liquid C prepared in Example 1 as the first layer of the sheet glass, the rotation was continued for 3 minutes, and then the liquid B was 0.9% in terms of SiO ₂ solid content. Then, 15 g of a silicate solution diluted with ethanol was dropped from a beaker onto a plate glass, and the rotation was further continued for 3 minutes. Then, the rotation was stopped. The glass substrate of the two-layer film coated in this manner is placed in an electric furnace at 180 ° C.
After heating for 0 minutes, the desired two-layer film was obtained.

The spectral characteristics of the formed film were evaluated in the same manner as in Example 1. While the visible light transmittance increased to 51.8%, the visible light reflectance was 4.6%, and the reflected light was extremely suppressed. Further, when a black tape was stuck on the back surface and the measurement was performed without reflection from the back surface, the visible light reflectance was 1.5%, and the appearance was close to that of non-reflective glass. The positions of the maximum value and the minimum value of the transmittance of this film are almost the same as those of the single-layer film in Example 1, and it is apparent that the film has the same heat ray shielding effect.

The visible light transmittance, the maximum / minimum value of the transmittance, and the surface resistance of the films formed in the following Examples 3 to 16 were evaluated in the same manner as described in Example 1, and Table 1 collectively includes the results of Examples 1 and 2.

Example 3 TiN having an average particle size of 40 nm
8 g of the fine particles, 80 g of isophorone, water and an appropriate amount of a dispersant were mixed, and the mixture was ball-milled using zirconia balls for 100 hours to prepare 100 g of a TiN isophorone dispersion. This is designated as solution D. As a binder, 50% by weight of an epoxy resin was dissolved in isophorone to prepare an epoxy resin binder solution. This is designated as solution E. Liquid D and E
The liquid and ethanol were mixed and stirred vigorously to prepare a coating liquid such that the solid content of TiN and the epoxy resin was 1.4% by weight and the weight ratio of TiN and the epoxy resin was 70:30, A coating solution was prepared in the same manner as in Example 1, and a film was formed and heated to obtain a film.

Example 4 A cold-setting silicate liquid X-40-9740 manufactured by Shin-Etsu Silicone was used as a binder.
Was used in place of the B solution to prepare a coating solution in the same manner as in Example 1, and formed into a film. However, without heating, 2
A film that was dried at room temperature of 5 ° C. for 2 days was evaluated.

Example 5 A low-temperature curing type polyperhydrosilazane solution manufactured by NE Chemcat Co., Ltd. was used as a binder instead of the solution E, and TiN shown in Example 3 was used.
The isophorone dispersion (solution D) and xylene were mixed and stirred to obtain a TiN concentration of 1.0% and a TiN / SiO ₂ ratio of 4:
This was used as a coating liquid so as to be 1. Using this, a film was formed in the same manner as in Example 1, and heated in an electric furnace at 80 ° C. to obtain a film.

Example 6 In the preparation of solution A, TiN
Was used in the same manner as in Example 1 except that ZrN fine particles having an average particle diameter of 35 nm were used instead of the above, and a coating film was prepared and heated to obtain a target film.

Example 7 In the preparation of solution A, TiN
Was used in the same manner as in Example 1 except that HfN fine particles having an average particle diameter of 47 nm were used, and a coating film was prepared and heated to obtain a target film.

Example 8 In the preparation of solution A, TiN
Was used in the same manner as in Example 1 except that VN fine particles having an average particle diameter of 64 nm were used instead of the above, and a coating film was prepared and heated to obtain a target film.

Example 9 In the preparation of solution A, TiN
Was used in the same manner as in Example 1 except that NbN fine particles having an average particle size of 55 nm were used instead of the above, and a coating film was prepared and heated to obtain a target film.

Example 10 In the preparation of solution A, Ti
A coating liquid was prepared in exactly the same manner as in Example 1 except that TaN fine particles having an average particle diameter of 43 nm were used instead of N, and this was formed and heated to obtain a target film.

Example 11 15 g of ruthenium oxide (RuO ₂ ) fine particles having an average particle diameter of 30 nm, N-methyl-2
-Mix 23 g of pyrrolidone (NMP), 57 g of diacetone alcohol (DAA), water and an appropriate amount of dispersant,
Using a zirconia ball having a diameter of 100 mm, ball mill mixing was carried out for 100 hours to prepare 100 g of a RuO ₂ dispersion. This R
In the uO ₂ dispersion, a RuO ₂ concentration of 1%, RuO ₂ : SiO ₂
= 4: 1, and the silicate liquid of the liquid B was mixed and stirred to obtain a RuO ₂ dispersed silicate liquid. This is designated as solution F. The solution A was mixed with the solution F so that the weight ratio of RuO ₂ : TiN = 1.0: 0.01, and the mixture was sufficiently stirred to prepare a coating solution. Using this coating solution, a film was formed and heated in exactly the same manner as in Example 1 to obtain a target film.

Example 12 At the time of mixing the solution F and the solution A,
A coating solution was prepared in exactly the same manner as in Example 11 except that the weight ratio of RuO ₂ : TiN was changed to 1.0: 0.25, and this was formed into a film and heated to obtain a target coating film.

Example 13 At the time of mixing the solution F and the solution A,
A coating solution was prepared in exactly the same manner as in Example 11 except that the weight ratio of RuO ₂ : TiN was changed to 1.0: 0.5, and this was formed into a film and heated to obtain a target coating film.

Example 14 At the time of mixing the solution F and the solution A,
A coating solution was prepared in exactly the same manner as in Example 11 except that the weight ratio of RuO ₂ : TiN was changed to 1.0: 1.0, and this was formed into a film and heated to obtain a target coating film.

Example 15 Ir having an average particle size of 28 nm
An IrO ₂ : TiN mixed and dispersed silicate coating solution was prepared, and the film was formed and heated to obtain a target film in exactly the same manner as in Example 11 except that O ₂ fine particles were used.

Example 16 Ir having an average particle size of 28 nm
An IrO ₂ : TiN mixed and dispersed silicate coating solution was prepared and formed into a film and heated to obtain a target film in exactly the same manner as in Example 12 except that O ₂ fine particles were used.

In the above Examples 1 to 16, for all the films, the maximum of the transmittance is between 400 and 700 nm, the minimum is between 700 and 1800 nm, and the difference between the maximum and the minimum is 15 It was confirmed that these films were useful as a heat-ray shielding film. In addition, all the films of the examples had a reflectance in the visible light region of 14% or less, no mirror-like glare, and had a surface resistance value of 10 ⁷ Ω / □ or more for all films, indicating radio wave transmittance. It was confirmed that there was no problem in.

Comparative Example 2 Ti having an average particle size of 120 nm
Except for using N, a TiN-dispersed silicate coating solution was prepared in exactly the same manner as in Example 1, and this was formed and heated to obtain a target film. However, this film was largely cloudy (hazing value: 14%), lacked transparency, and became bluish-gray, and was judged to be difficult to be practically used as a heat ray shielding film.

Comparative Example 3 ITO having an average particle size of 22 nm
Except for using ultrafine particles, I
A TO-dispersed silicate coating solution was prepared, formed into a film, and heated to obtain a target film. However, this film had a transmittance of 90% or more from the visible light region to the infrared region of 1500 nm, and it was found that this film could not be used at this concentration for the purpose of shielding near infrared light.

[0066]

[Table 1]

[0067]

As shown in the above embodiments, according to the present invention, the transmittance of light in the visible light region is high and the reflectance is low, and the transmittance of light in the near infrared region is low and the reflection is low. A coating solution that can form a film having a high rate and a film conductivity of approximately 10 ⁶ Ω / □ or more by a simple coating method without using a high-cost physical film forming method; A heat ray shielding film could be provided.
The film of the present invention is a heat ray shielding film which has less glare on the surface and is excellent in radio wave permeability as compared with the conventional film. In addition, the use of the coating liquid of the present invention has high industrial utility in terms of cost and large-area film.

[Brief description of the drawings]

FIG. 1 is a graph showing the transmittance of Examples 1, 11, 12, 13, and 14 of the present invention.

FIG. 2 is a graph showing the reflectance of Examples 1, 11, 12, 13, and 14 of the present invention.

Claims (9)

[Claims] 1. A titanium nitride fine particle having an average particle diameter of 100 nm or less, a zirconium nitride fine particle having an average particle diameter of 100 nm or less, a hafnium nitride fine particle having an average particle diameter of 100 nm or less,
A coating liquid for forming a heat ray shielding film, in which at least one of vanadium nitride fine particles having an average particle diameter of 100 nm or less, niobium nitride fine particles having an average particle diameter of 100 nm or less, and tantalum nitride fine particles having an average particle diameter of 100 nm or less is dispersed. 2. Titanium nitride fine particles having an average particle size of 100 nm or less, zirconium nitride fine particles having an average particle size of 100 nm or less, hafnium nitride fine particles having an average particle size of 100 nm or less,
Vanadium nitride fine particles having an average particle size of 100 nm or less, niobium nitride fine particles having an average particle size of 100 nm or less, and at least one of tantalum nitride fine particles having an average particle size of 100 nm or less, and ruthenium oxide fine particles having an average particle size of 100 nm or less, A coating liquid for forming a heat ray shielding film, comprising at least one kind of iridium oxide fine particles having an average particle diameter of 100 nm or less. 3. The coating solution for forming a heat ray shielding film according to claim 1, further comprising a metal alkoxide of silicon, zirconium, titanium, or aluminum, or a partial hydrolysis polymerization of a metal alkoxide. A coating solution for forming a heat ray shielding film, comprising at least one of the following: 4. The coating solution for forming a heat ray shielding film according to claim 1, further comprising a resin binder. 5. A fine particle dispersed film obtained by applying the coating solution for forming a heat ray shielding film according to any one of claims 1 to 4 to a substrate, followed by heating. , Titanium nitride, zirconium nitride, hafnium nitride, vanadium nitride, niobium nitride, tantalum nitride, ruthenium oxide,
And at least one kind of fine particles of iridium oxide, wherein the fine particle component is contained in a resin binder, or
A heat ray shielding film dispersed in an oxide binder containing at least one of metal oxides of silicon, zirconium, titanium, and aluminum. 6. A heat ray shielding film obtained by applying the heat ray shielding film forming coating solution according to any one of claims 1 to 4 to a substrate and then heating, further comprising silicon, zirconium, titanium, and And a multilayer heat ray shielding film coated with an oxide film containing at least one of metal oxides of aluminum. 7. A resin film is further coated on the heat ray shielding film obtained by applying the heat ray shielding film forming coating liquid according to any one of claims 1 to 4 to a substrate and heating the same. Multilayer heat ray shielding film. 8. The transmittance has a maximum value at a wavelength of 400 to 700 nm, a minimum value at a wavelength of 700 to 1800 nm, and a difference between the maximum value and the minimum value is 15 points or more in percentage. The heat ray shielding film according to claim 7. 9. The heat ray shielding film according to claim 5, which has a surface resistance value of 10 ⁶ Ω / □ or more.