JPH11258418A - Coating liquid for forming heat-ray-shielding film and heat-ray-shielding film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a coating liquid from which a film having high transmittance and low reflectance in the visible light region and low transmittance and high reflectance in the near infrared region and film conductivity controllable to be about 10<6> Ω/(square) or higher can be formed by a simple coating method without requiring a costly physical film formation method and to provide a heat-ray shielding film produced from the coating liquid. SOLUTION: This coating liquid is a dispersant containing fine particles silicides of one or more metals selected from Cr, Mn, Co, Ni, Re, Mo, W, Ti, Zr, Hf, V, Nb, and Ta with an average particle diameter of 100 nm or smaller and alternatively further containing one or more fine particles of ruthenium oxide and iridium oxide with an average particle diameter of 100 nm or smaller. This heat ray-shielding film is obtained by applying any of such a coating liquid to a substrate and then drying the substrate.

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 materials for heat ray reflection, metal oxides such as FeO _x , CoO _x , CrO _x , and TiO _x and metal materials having a large amount of free electrons such as Ag, Au, Cu, Ni, and Al are 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 generally practiced to form an extremely thin film having a thickness of 10 nm 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 increase in area, and have a high film manufacturing cost.

[0005] Further, when these films are made thinner to increase the transmittance, the heat ray shielding characteristics are degraded. Conversely, when the film thickness is increased to increase the heat ray shielding characteristics, the films become darker. Further, when the heat ray shielding properties of these materials are to be enhanced, the reflectance in the visible light region tends to be increased at the same time, giving a glare-like appearance like a mirror and impairing the aesthetic appearance.

Further, many of these materials have high conductivity of the film. If the conductivity of the film is high, mobile phones and 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 problems of the prior art, and has a high transmittance of light in the visible light region, a low reflectance, and a low transmittance of light in the near infrared region. A coating solution that can form a film having high reflectivity and a film conductivity of approximately 10 ⁶ Ω / □ or more by a simple coating method without using an expensive physical film forming method; It is an object to provide a heat ray shielding film used.

[0010]

Means for Solving the Problems In order to achieve the above object, the present inventors have focused on a silicon compound having a large amount of free electrons as a characteristic of the material itself. By producing a highly dispersed film that has a high transmittance in the visible light region, strong plasma reflection is exhibited in the near infrared region near the visible light region, and the transmittance is minimized. The present invention was completed by finding the phenomenon of becoming "a".

That is, the coating solution for a heat ray shielding film of the present invention comprises Cr, Mn, Co, Ni, Re, Mo, W, Ti,
It is characterized by comprising a dispersion liquid containing fine particles of a silicon compound having an average particle diameter of 100 nm or less of one or more metals selected from the group consisting of Zr, Hf, V, Nb, and Ta.

Further, other coating liquids for forming a heat ray shielding film of the present invention include Cr, Mn, Co, Ni, Re, Mo, W, T
i, Zr, Hf, V, Nb, and one or more metals selected from the group of Ta having an average particle size of 100 nm
It is characterized by comprising a dispersion containing the following silicon compound fine particles, ruthenium oxide fine particles having an average particle diameter of 100 nm or less, and 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 by comprising a dispersion containing at least one of the above.

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. , Cr, Mn, Co, Ni, Re, Mo, W, Ti,
Fine particles of a silicon compound of one or more of Zr, Hf, V, Nb, and Ta, and the fine particles are contained in a resin binder or a metal of silicon, zirconium, titanium, and aluminum. It is characterized by being dispersed in an oxide binder containing at least one of the oxides.

Further, an oxide film containing at least one of metal oxides of silicon, zirconium, titanium and aluminum is coated on the heat ray shielding film, or Further, a multilayer heat ray shielding film may be formed by coating a resin film.

[0017] Any 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 is characterized by having a minimum value at 00 nm, a difference between the maximum value and the minimum value of the transmittance of 15 points or more in percentage, and a surface resistance value of 10 ⁶ Ω / □ or more. And

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Silicon compound fine particles used in the present invention include titanium silicide (TiSi ₂ ), cobalt silicide (CoSi ₂ .CoSi), and tungsten silicide (WSi).
i ₂ ), molybdenum silicide (MoSi ₂ ), niobium silicide (N
bSi ₂ ), vanadium silicide (VSi ₂ ), chromium silicide (CrSi, Cr ₃ Si, CrSi ₂ ), manganese silicide (MnSi, MnSi ₂ ), nickel silicide (NiS
i), fine particles such as rhenium silicide (ReSi ₂ ) are typical examples thereof.

The fine particles of the silicon compound used in the present invention are preferably not oxidized on the surface, but are usually slightly oxidized in many cases. Is inevitable to some extent. However, even in that case, there is no change in the effectiveness of exhibiting the heat ray shielding effect.

Further, these silicon compound fine particles have a higher heat ray shielding effect as the crystal perfection becomes higher, but have a low crystallinity and generate an extremely broad diffraction peak in X-ray diffraction. Also, if the basic bond inside the fine particles is made up of the bond between each metal and silicon, a heat ray shielding effect is exhibited.

The fine particles of ruthenium oxide and iridium oxide used in the present invention include ruthenium dioxide (RuO ₂ ), 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)
Fine particles such as ₂ O ₇ ) and lead iridate (Pb ₂ Ir 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 silicon compound fine particles, ruthenium oxide fine particles, and iridium oxide fine particles are powders colored dark black, brown black, green black, etc., and have a particle size sufficiently smaller than the wavelength of visible light to be dispersed in a thin film. In this state, the film becomes transparent to visible light. 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 an experiment, a film in which these fine particles are sufficiently finely and uniformly dispersed has a transmittance of 400 to 70 wavelength.
It has a maximum value at 0 nm and a wavelength of 700 to 1800 n
It is observed that m has a minimum value, and that the difference between these maximum value and minimum value is sufficiently large as a percentage of 15 points or more. Considering that the visible light wavelength is 380 to 780 nm and that the visibility is a bell-shaped peak with a peak around 550 nm, such a film effectively transmits visible light and effectively reflects and absorbs other heat rays. I can understand.

In the present invention, the average particle diameter of the silicon compound fine particles, ruthenium oxide fine particles, and iridium oxide fine particles in the coating solution is preferably 100 nm or less. Particle size 100nm
If it is larger, the specific transmittance profile as described above, that is, the transmittance is 400 to 700 nm in wavelength
Has a local maximum value, and has a local minimum value at a wavelength of 700 to 1800 nm, and the difference between the local maximum value and the local minimum value is 1% in percentage.
I couldn't get a profile with more than 5 points,
It becomes a grayish film with a monotonous decrease in transmittance. 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. Further, fine particles having a size of 100 nm or more or coarse particles aggregated thereof are not preferable because they act as a light scattering source and cause clouding (haze) of the film or decrease in visible light transmittance. Therefore, the average particle diameter of the inorganic fine particles is 1
It is necessary to be less than 00 nm. Note that the minimum particle size economically available with the current technology is about 2 nm, but the adjustment is not limited to this.

The dispersion medium of the fine particles in the coating solution is not particularly limited, and can be selected according to the coating conditions, coating environment, alkoxide in the coating solution, synthetic resin binder, and the like. For example, various organic solvents such as water, alcohols, ethers, esters, and ketones can be used, and the pH may be adjusted by adding an acid or an alkali as needed.

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 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 the alkoxide of each metal of silicon, zirconium, titanium and aluminum, or the partially hydrolyzed polymer of these metals, or the content of the 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 above-mentioned fine particles are deposited on a substrate at a high density to form a film, and each metal alkoxide of silicon, zirconium, titanium and aluminum contained in the coating solution, or These partially hydrolyzed polymers of metal alkoxides or synthetic resin binders have the effect of improving the binding properties of the fine particles to the base material after coating and curing, and further improving the hardness of the film. Further, a film containing a metal alkoxide such as silicon, zirconium, titanium, or aluminum, a hydrolyzed polymer of these metal alkoxides, or a synthetic resin is further applied 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 each metal alkoxide of aluminum, or a hydrolysis polymer of these metal alkoxides, or a synthetic resin binder is not contained, a film obtained after applying this coating solution to a substrate is a film in which only the fine particles are deposited on the substrate. Structure. Although the heat ray shielding effect is exhibited as it is, the coating liquid containing an alkoxide of each metal of silicon, zirconium, titanium, and aluminum, or a hydrolyzed polymer of these metals, or a synthetic resin binder is applied to the film as described above. By forming a coating film to form a multilayer film, the coating liquid component is formed to fill the gaps where the fine particles of the first layer are deposited, so that the haze of the film is reduced and the visible light transmittance is improved. Of the base material to the base material is improved.

As a method of binding the film containing the fine particles as a main component with a film made of alkoxide of each metal of silicon, zirconium, titanium, and aluminum, or a hydrolyzed polymer of these metals, a sputtering method or a vapor deposition method is used. Although a coating method is also possible, a coating method is effective from advantages such as easiness of a film forming process and low cost. The coating liquid for coating contains at least one alkoxide of each metal of silicon, zirconium, titanium, and aluminum, or a hydrolyzed polymer of these metal alkoxides in water or alcohol. 4 in the total solution in terms of oxides
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 film is not particularly limited, and treatment liquids such as spin coating, spray coating, dip coating, screen printing, roll coating, and flow coating are used. Any method can be used as appropriate as long as it is a method that can be applied uniformly and thinly.

The substrate heating temperature after application of the coating solution containing each of the above metal alkoxides and their hydrolyzed polymers is 100
Below ℃, the polymerization reaction of the alkoxide and the hydrolyzed polymer contained in the coating film often remains uncompleted, and water and organic solvents remain in the film, and the visible light transmittance of the film after heating is reduced. 100 ° C. or higher is preferable because it causes reduction.
More preferably, heating is 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 less due to modification of a side chain group or addition of an oxidation catalyst are commercially available. 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. In both cases, an inorganic film of SiO ₂ is formed after curing, and 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 above-mentioned ultrafine particles are dispersed, a film having a mirror-like surface in which crystals are densely filled like a thin oxide film produced by a physical film formation method is used. By comparison, reflection in the visible light region is small, and it is possible to avoid giving a glaring appearance. On the other hand, in order to have a plasma frequency in the visible to near infrared region as described above,
It has a very favorable characteristic that the plasma reflection accompanying this becomes large in the near infrared region. When it is desired to further suppress the reflection in the visible light region, a low-refractive-index film such as SiO ₂ or MgF is easily formed on the fine particle-dispersed film so that the luminous reflectance is 1% or less. Multilayer films can be manufactured.

In order to improve the transmittance, the coating liquid 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. And ATO and I
It is also possible to add the coating liquid of the present invention to a liquid in which ultrafine particles such as TO or 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 by a very small amount of addition to the main ITO or the like, 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 also contains titanium oxide, zinc oxide, cerium oxide, etc., 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 formed into a film. It is also possible to add one or more of inorganic fine particles and organic benzophenone and benzotriazole.

The coating liquid according to the present invention is a dispersion in which the above-mentioned inorganic fine particles are dispersed, and does not form a target heat ray shielding film by utilizing decomposition or a chemical reaction of coating components due to heat during baking. A permeable film having a stable and uniform film thickness can be formed.

The fine particle-dispersed film of the present invention is a film in which fine particles are deposited on a substrate at a high density to form a film, and the alkoxide of each metal of silicon, zirconium, titanium, and aluminum contained in the coating solution or these alkoxides. The hydrolysis polymer 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 has the effect of 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 particles. 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.

[0042]

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

Example 1 CoS having an average particle diameter of 69 nm
i ₂ particles 8 g, diacetone alcohol (DAA) 80
g, water and an appropriate amount of a dispersant, and ball mill mixing using zirconia balls having a diameter of 4 mm for 100 hours to obtain Co.
100 g of a Si ₂ dispersion was prepared. This is designated as solution A.
6 g of ethyl silicate 40 (manufactured by Tama Chemical Industry Co., Ltd.) having an average degree of polymerization of 4 to 5 and ethanol 31 g, 5%
50 g of an ethyl silicate solution prepared with 8 g of a hydrochloric acid aqueous solution and 5 g of water, 800 g of water, and 300 g of ethanol were thoroughly mixed and stirred, and 1150 g of an ethyl silicate mixed solution was obtained.
Was prepared. This is designated as solution B.

The solution A and the solution B were used when the CoSi ₂ concentration was 1.0
% And a ratio such that the CoSi ₂ / SiO ₂ ratio is 4: 1 to form a coating solution. This is designated as liquid C.
Rotate 15 g of this solution at 145 rpm 200 × 20
The solution was dropped from a beaker onto a 0 × 3 mm soda-lime glass substrate, shaken for 3 minutes, and then stopped rotating.
This was placed in an electric furnace at 240 ° 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. According to the transmission profile of the film of this example using CoSi ₂ fine particles, the maximum value of the transmittance is 507 nm, the minimum value is 1029 nm, the difference between the maximum value and the minimum value is 36 points, which is sufficiently large.
Based on SR-3106, a visible light transmittance of 64.3% was obtained as a net value of the film.

The transmission color of the film according to this example was a beautiful dark green. Further, the visible light reflectance was as low as 7.2%, and no glare on the film surface was felt at all like a commercially available heat ray reflective glass.

Further, the surface resistance value of this film was measured using a surface resistance meter manufactured by Mitsubishi Chemical Corporation to find that it was 5.3 × 10 ¹² Ω /.
□ was obtained, and it was found that there was no problem in radio wave transmission because the film resistance was sufficiently high.

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. The light transmittance was determined to be 38.8%. Further, the visible light reflectance was as high as 34.2%, and the appearance was a mirror-like appearance. The surface resistance of the film surface is 83Ω /
It is clear that there is a problem in radio wave transmission and reflection, as low as □.

(Example 2) The solution C prepared in Example 1 was spin-coated as the first layer of the sheet glass, and the rotation was continued for 3 minutes, and then the solution 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 240 ° 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. Although the visible light transmittance increased to 66.8%, the visible light reflectance was 3.4%, and the reflected light was further suppressed. Further, when a black tape was adhered to the back surface and the measurement was performed without reflection from the back surface, the visible light reflectance was 0.4%, 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 films formed in the following Examples 3 to 13 and Comparative Examples 2 to 3 have the same visible light transmittance, maximum and minimum values of transmittance, and surface resistance as those described in Example 1. Table 1 shows the results of Examples 1 and 2
It was shown to.

Example 3 CoS having an average particle size of 69 nm
i ₂ particles 8 g, isophorone 80 g, water and a dispersing agent suitable amount are mixed, and mixed 100 hours in a ball mill containing zirconia balls to prepare a CoSi ₂ isophorone dispersion 100 g. 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. D
Solution, E solution and ethanol are mixed and stirred vigorously to obtain CoS
i ₂ and the solid content of the epoxy resin are 1.4% by weight of the total, C
A coating liquid was prepared so that the weight ratio of oSi ₂ to the epoxy resin was 70:30, and a coating liquid was prepared in the same manner as in Example 1, and a film was formed and heated to obtain a film.

(Example 4) As a binder, a cold-setting silicate solution X-40-9740 manufactured by Shin-Etsu Silicone Co., Ltd.
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 the CoS shown in Example 3 was used.
The i ₂ isophorone dispersion (solution D) and xylene were mixed and stirred to give a CoSi ₂ concentration of 1.0% and a CoSi ₂ / SiO
This was used as a coating liquid so that the ratio of ₂ was 4: 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, CoS
except that in place of i ₂ with WC particles having an average particle diameter of 81nm, the Example 1 exactly to prepare a coating solution in the same manner to obtain the desired film which was deposited and heating.

Example 7 In the preparation of solution A, CoS
A coating solution was prepared in exactly the same manner as in Example 1, except that TiSi ₂ fine particles having an average particle size of 51 nm were used instead of i ₂ .
This was deposited and heated to obtain a target film.

Example 8 In the preparation of solution A, CoS
A coating solution was prepared in exactly the same manner as in Example 1 except that ZrSi ₂ fine particles having an average particle size of 48 nm were used instead of i ₂ ,
This was deposited and heated to obtain a target film.

Example 9 In the preparation of solution A, CoS
A coating solution was prepared in exactly the same manner as in Example 1 except that NiSi ₂ fine particles having an average particle size of 60 nm were used instead of i ₂ ,
This was deposited and heated to obtain a target film.

Example 10 In the preparation of solution A,
A coating liquid was prepared in exactly the same manner as in Example 1 except that TaSi ₂ fine particles having an average particle diameter of 50 nm were used instead of Si ₂ , and the coating liquid was formed and heated to obtain a target film.

Example 11 In the preparation of solution A,
A coating solution was prepared in exactly the same manner as in Example 1 except that NbSi ₂ fine particles having an average particle size of 83 nm were used instead of Si ₂ , and this was formed and heated to obtain a target film.

(Example 12) 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 : CoSi ₂ = 1.0: 1.0, 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 13 Ir having an average particle size of 28 nm
A mixed dispersion silicate coating liquid of IrO ₂ : CoSi ₂ = 1: 1 was prepared in the same manner as in Example 11 except that the O ₂ fine particles were used, and this was formed and heated to obtain a target film. Was.

In the above Examples 1 to 13, for all the films, the maximum of the transmittance is in the wavelength of 400 to 700 nm, the minimum value is in the wavelength of 700 to 1800 nm, and the difference between the maximum value and the minimum value is It was observed that the percentage was 15% or more, and it was confirmed that these films were useful as heat ray shielding films. In addition, all of the films have a reflectance of 8% or less in the visible light region, have no mirror-like glare, and have a surface resistance of 3.5 × 10 ¹¹ Ω / □ or more. It was confirmed that there was not.

Comparative Example 2 Co having an average particle size of 174 nm
Except that Si ₂ was used, Co
An Si ₂ dispersed silicate coating solution was prepared, and formed into a film and heated to obtain a target film. However, since this film has a too large particle size, it has a large haze (haze value of 33%), lacks transparency, becomes slightly greenish gray, and has a small difference of 9% between the maximum value and the minimum value. Therefore, it was judged that it was difficult to practically use 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 has a transmittance of 90% or more from the visible light region to the infrared region of 1500 nm.
%) Cannot be used.

[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.

Claims (9)

[Claims] 1. Cr, Mn, Co, Ni, Re, Mo,
Average particle size of one or more metals selected from the group consisting of W, Ti, Zr, Hf, V, Nb, and Ta
A coating solution for forming a heat ray shielding film, comprising a dispersion containing silicon compound fine particles of 0 nm or less. 2. Cr, Mn, Co, Ni, Re, Mo,
Average particle size of one or more metals selected from the group consisting of W, Ti, Zr, Hf, V, Nb, and Ta
0 nm or less silicon compound fine particles and an average particle diameter of 100 nm
The following ruthenium oxide fine particles and an average particle diameter of 100
A coating liquid for forming a heat ray shielding film, comprising a dispersion liquid containing at least one of iridium oxide fine particles having a diameter of not more than nm. 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 liquid for forming a heat ray shielding film, comprising a dispersion containing at least one of the following substances. 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. , C
r, Mn, Co, Ni, Re, Mo, W, Ti, Zr,
One or two of Hf, V, Nb, and Ta
Fine particles of a silicon compound of at least one kind of metal, and the fine particles are dispersed in a resin binder or an oxide binder containing one or more of metal oxides of silicon, zirconium, titanium, and aluminum. Heat shielding film. 6. A heat ray shielding 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 and then heating, further comprising silicon, zirconium, titanium, And a multilayer heat ray shielding film coated with an oxide film containing one or more of aluminum metal oxides. 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 method according to claim 1, wherein 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 of the transmittance is 15 points or more as a percentage. The heat ray shielding film according to any one of claims 5 to 7. 9. The heat ray shielding film according to claim 5, which has a surface resistance value of 10 ⁶ Ω / □ or more.