JP2002155238A - Coating liquid for forming transparent heat ray- and ultraviolet-screening film for sponge coating - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain both a coating liquid for forming a film having a high transmittance of light in a visible region and efficiently screening heat rays in a near infrared region and ultraviolet rays in sunlight and having excellent durability in situ by a sponge coating method and a transparent heat ray- and ultraviolet-screening film using the same coating liquid. SOLUTION: This coating liquid is obtained by including >=0.1 and <=1 mass% of ruthenium dioxide particles having <=50 μ average particle diameter, >=1 and <=10 mass% of iron oxyhydroxide and/or cerium dioxide fine particles having <=100 nm average particle diameter and >=1 and <=6 mass% of a benzophenone and/or a benzotriazole organic ultraviolet light absorbing material. The components are dispersed in a diluting solvent and a room temperature curing binder is added to form the coating liquid. The resultant coating liquid has >=2 and <=20 mPa.s (>=2 and <=20 cP) viscosity at normal temperature. A substrate is coated with the coating liquid by the sponge coating method and the coating liquid is then cured at normal temperature or by hot-air drying.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating solution for forming a transparent heat and ultraviolet ray shielding film, and more particularly to a vehicle, a building, an office,
Sponge coat method is applied on glass, plastic, and other transparent base materials such as windows, telephone boxes, show windows, lighting lamps, etc. of ordinary houses by sponge coating method, and it blocks heat rays and ultraviolet rays in sunlight. Coating liquid to obtain
And a transparent heat ray / ultraviolet ray shielding film obtained thereby.

[0002]

2. Description of the Related Art Due to the generation and expansion of an ozone hole, the amount of ultraviolet rays reaching the ground surface has been significantly increased, and adverse effects on the human body such as sunburn and skin cancer have become a problem. Also, housing,
Ultraviolet rays enter through windows of buildings, automobiles, show windows, etc., and discoloration, fading, and deterioration of interior curtains, carpets, furniture such as sofas, paintings, documents, and the like have become problems.

Further, from the viewpoint of energy saving, glass (functional glass) which blocks infrared rays of sunlight to reduce the cooling load in summer or reduces the transmittance in the visible light region to reduce the heat felt on the skin (functional glass) ) Has attracted attention in recent years.

As described above, a thin film is formed on the surface of a transparent plastic or glass to remove harmful ultraviolet rays and unnecessary near-infrared rays as much as possible from sunlight, and to pass only visible light. The demand for ultraviolet shielding films is increasing.

Conventionally, such functional films are mostly produced by a dry method such as a sputtering method or a vapor deposition method, so that large-scale equipment and complicated steps are required, and the cost as a product is also low. Was very expensive. In addition, the dry method is useful for manufacturing and supplying functional glass, but it is difficult to respond to the demand to cut heat rays and ultraviolet rays by installing it on existing window glass on the spot. .

As a method that can be applied to existing window glass on the spot, there are a film sticking method and a coating method using a functional coating solution. Both have the advantage that the apparatus is simpler and less expensive than the dry method, and that the film can be formed on the spot.

However, film sticking has problems in durability, such as generation of air bubbles on the glass bonding surface and discoloration or fading of the film itself under the influence of ultraviolet rays, and seams occur in large glass.

On the other hand, according to the coating method, durability can be easily obtained by selecting a binder, and a seam can be avoided by a coating method such as a flow coat or a sponge coat using a long bar. be able to.

Antimony-containing tin oxide (ATO) and tin-containing indium oxide (ITO) are known as materials for shielding heat rays by using a coating method. These materials are made into a coating solution with a diluting solvent and a room temperature curing binder. The film formed with this coating liquid is effective in shielding heat rays while maintaining transparency, but since the plasma wavelength is on the relatively long wavelength side in the near infrared region, infrared rays included in sunlight The effect of reflection and absorption was not sufficient.

[0010] A coating solution for forming a heat ray shielding film using an organic dye or pigment is also commercially available, but has a serious problem in durability due to remarkable decomposition by sunlight.

[0011] Further, various types of coating liquids for forming an ultraviolet shielding film which are transparent are commercially available, but all of them contain an organic ultraviolet absorbing component in a room temperature curing binder.
In many cases, the durability was poor, and the ultraviolet shielding effect disappeared in about six months.

[0012]

Problems to be Solved by the Invention ATO fine particles and ITO
If the fine particles are added in a large amount to the coating solution, the cost increases, but the solar radiation transmittance can be reduced. Therefore,
The present inventors have prepared a coating solution containing these in an amount of 15 to 30% by mass and tried sponge coating. However, since the viscosity is high, it is very difficult to obtain a uniform coating film, Since there are many components, the strength of the coating film is lowered, and further, the haze of the coating film is large.

The present invention solves the above-mentioned problems of the prior art, has a high light transmittance in the visible light region, efficiently blocks heat rays and ultraviolet rays in the near infrared region of sunlight, and has excellent durability. It is an object of the present invention to provide a coating liquid capable of forming a deposited film in situ by a sponge coating method, and a transparent heat ray ultraviolet shielding film using the same.

[0014]

Means for Solving the Problems The coating liquid for forming a transparent heat ray ultraviolet shielding film for sponge coating according to the present invention has an average particle diameter of 50.
0.1 mass% or more and 1 mass% or less of ruthenium dioxide fine particles having a diameter of 1 nm or less, 1 mass% or more and 10 mass% or less of iron oxide hydroxide and / or cerium dioxide fine particles having an average particle diameter of 100 nm or less, and benzophenone-based and / or 1% by mass or more of benzotriazole-based organic ultraviolet absorbing material
It is characterized by containing not more than mass%. According to the prior art, these components are dispersed in a diluting solvent, and a coating solution is formed by adding a room temperature curing binder. Further, the room temperature viscosity is 2 mPa · s or more and 20 mPa · s or less (2 cP or more,
20 cP or less).

The present invention further provides a transparent ultraviolet ray shielding film obtained by applying these coating solutions to a substrate by a sponge coating method and then curing the coating solution at room temperature or drying with hot air.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention provides a coating solution suitable for the sponge coating method in order to use a sponge coating method suitable for window glass application on site.

The coating solution comprises ruthenium dioxide ultrafine particles,
It is composed mainly of iron oxide hydroxide ultrafine particles, cerium dioxide ultrafine particles, an organic ultraviolet absorber, a cold curing binder, and a dispersing and diluting solvent.

Although ultrafine ruthenium dioxide having a large amount of free electrons is a black powder, when it is highly dispersed in a transparent binder, the coating film becomes transparent,
Further, compared to ITO or ATO, even a very small amount of addition has an effective heat ray shielding effect. Therefore, the viscosity of the coating solution is suppressed to be low, and a uniform thin film without image distortion can be formed by sponge coating. Due to the action of ruthenium dioxide, it has a maximum transmittance in the visible light region and exhibits strong reflection and absorption in the near infrared region near the visible light region, thereby exhibiting a heat ray shielding function. Further, by introducing an appropriate amount of an inorganic or organic ultraviolet absorbing material, a heat ray ultraviolet shielding film can be formed.

It is preferable that the inorganic ultraviolet absorbing material and the organic ultraviolet absorbing material are used in combination.

The coating liquid is adjusted so that the viscosity at room temperature is 2 mPa · s or more and 20 mPa · s or less (2 cP to 20 cP). Room temperature viscosity of coating liquid is 2mPa · s
In the following cases, the wet film thickness after sponge coating is too thin, causing optical interference with the substrate glass after drying, resulting in a rainbow interference color, which is not preferable in appearance. On the other hand, if the room temperature viscosity is 20 mPa · s or more, the wet film thickness after sponge coating becomes large, the leveling of the liquid becomes insufficient, and the film thickness unevenness occurs after drying.

Hereinafter, the components in the coating solution will be described.

Heat ray shielding component Ruthenium dioxide fine particles (Ru) used in the present invention
O ₂ ) is generally commercially available as a black powder. When the ruthenium dioxide is dispersed in a thin film as fine particles having a particle diameter of 100 nm or less, visible light transmittance is generated. However, ruthenium dioxide material has a lot of free electrons and its plasma resonance wavelength is just visible.
Since it is near the near infrared, heat rays in this wavelength range are selectively reflected and absorbed.

According to an experiment, a film in which ruthenium dioxide fine particles are sufficiently finely and uniformly dispersed has a transmittance of 5 wavelengths.
It is observed that it has a local maximum near 70 nm, a local minimum near a wavelength of 1000 nm, and a difference between the maximum value and the minimum value of the transmittance of 15 points or more. The visible light wavelength is 380-780 nm, and the visibility is 550.
Considering that the film has a bell shape having a peak near nm, it is understood that such a film effectively transmits visible light and effectively reflects and absorbs other heat rays.

Since the heat ray shielding effect of ruthenium dioxide depends on the ratio to the binder component and the dry film thickness, it cannot be defined solely by the content alone. However, in ordinary use in the sponge coating method, The content of ruthenium dioxide is preferably used between 0.1% by mass and 1.0% by mass. At a content of 0.1% by mass or less, it is difficult to obtain a sufficient heat ray shielding effect even if the film thickness is increased using a known binder component.
When the content exceeds 0% by mass, the visible light transmittance of the coating film is reduced to 60% or less, and it is difficult to obtain a uniform finish with no unevenness in the transmittance by the sponge coating method.

In the present invention, the particle size of the ruthenium dioxide fine particles in the coating solution needs to be 100 nm or less. 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, light scattering increases, which causes clouding (haze) in the coating film and causes a decrease in visible light transmittance.
In addition, the absorption effect of near-infrared light is reduced. Therefore,
The average particle size of the ruthenium dioxide fine particles is 100 nm.
It is necessary to: The smaller the particle size, the more preferable the transmittance of the coating film is. However, the lowest particle size economically available with the current technology is about 2 nm, so this is the lower limit particle size.

Ultraviolet ray shielding component The inorganic ultraviolet ray shielding component used in the present invention includes iron oxide hydroxide (FeOOH) or cerium oxide (Ce).
O ₂ ) is used. These oxide fine particles have an absorption band in the ultraviolet to visible range and absorb ultraviolet rays. Further, since it is an inorganic substance, it is less deteriorated by ultraviolet rays and moisture, and has stability over time. In general, other inorganic materials that absorb ultraviolet rays include iron oxide (Fe ₂ O ₃ ) and titanium oxide (TiO ₂ ).
₂ ), zinc oxide (ZnO) and the like are also well known.

Although Fe ₂ O ₃ has the highest ultraviolet shielding efficiency, it also absorbs in the visible light region exceeding 380 nm, so that the coating film is colored brown or brown, which is undesirable in appearance.

TiO ₂ has a relatively low shielding effect, has a strong catalytic action on the surface of the fine particles, and deteriorates the resin and binder components coexisting in the coating solution and shortens the pot life of the coating solution. .

ZnO has a strong catalytic action on the surface of fine particles,
It is not preferable because the resin and the binder component coexisting in the coating liquid are deteriorated and the pot life of the coating liquid is shortened.

Therefore, in the present invention, FeOOH and CeO ₂
Was used. The addition amount of these is preferably 1.0% by mass or more and 10% by mass or less in total. If the addition is less than 1.0% by mass, a sufficient ultraviolet shielding effect cannot be obtained. If the addition exceeds 10% by mass, the viscosity of the coating solution is increased and the leveling property of the coating solution is reduced, and the sponge coating is performed. And it becomes difficult to apply uniformly. Also,
An excessively large amount is not preferable because the coating film is colored yellow or orange.

In the present invention, the particle size of the inorganic ultraviolet absorbing oxide fine particles in the coating solution needs to be 100 nm or less. 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, light scattering increases, which causes clouding (haze) in the coating film and causes a decrease in visible light transmittance.

As the organic ultraviolet absorbing component used in the present invention, a benzophenone-based or benzotriazole-based compound having a large absorption effect is preferred, but other commercially available organic compounds such as triazine-based, oxalic anilide-based, cyanoacrylate-based and salicylate-based components can be used. Materials can also be used. Examples of benzophenone-based ultraviolet absorbers include, for example, 2,4.
-Dihydroxybenzophenone, 2-hydroxy-4-
Octyloxybenzophenone is a benzotriazole-based ultraviolet absorber, for example, 5-chloro-
2- (2'-hydroxy-3 ', 5'-di-tert-
Butylphenyl) benzotriazole, 2- (2′-hydroxy-5′-methylphenyl) benzotrizole and the like are known.

These organic ultraviolet absorbing materials have remarkably excellent absorption efficiencies as compared with inorganic ultraviolet absorbing materials, but when added at 1% by mass or less, a sufficient shielding effect cannot be obtained. When a large amount is added, bleeding or precipitation easily occurs due to the influence of heat or moisture in the air. To avoid this, a small amount of about 6% by mass or less is preferable.

Since these organic ultraviolet absorbing components are deteriorated by ultraviolet rays or oxygen in the air, a light stabilizer (HALS), a peroxide decomposer, a quencher and the like may be appropriately added to the coating solution. It is possible.

Room temperature curable binders Room temperature curable binders include, for example, acrylic resins, urethane resins, silane coupling agents, silicates, organocizaranes, etc., which can be cured at 100 ° C. or lower. Have been. These can be diluted and dissolved in a solvent that does not break the dispersion of the fine particles, and mixed to form a coating solution. However, when the viscosity of the coating liquid is 20 mPa · s or more at room temperature, the wet film thickness after sponge coating becomes large, leveling of the coating liquid becomes insufficient, and unevenness in film thickness occurs in the finish. Therefore, when a room temperature curing binder utilizing a polymerization reaction of a polymer is used, it is preferable to avoid a high-molecular-weight binder having a higher degree of polymerization.

Sponge-coated coating films obtained by adding various amounts of isobutyl alcohol to a solvent heat ray ultraviolet ray shielding coating solution and sponge-coating the coating film become thinner according to the dilution ratio, and the transmittance increases sequentially.

The dispersion solvent and dilution solvent for the fine particles in the coating solution are not particularly limited, and can be selected according to the coating conditions, coating environment, binder in the coating solution, and the like. Various organic solvents such as alcohols such as isopropyl alcohol, ether alcohols such as ethylene glycol monomethyl ether and ethylene glycol monoethyl ether, and ketones such as methyl ethyl ketone and diacetone alcohol can be used. However, solvents such as diacetone alcohol and ketones cause deterioration and swelling of the sponge.

Additives If necessary, a small amount of 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 solution, it is possible to add various surfactants, coupling agents and the like. However, components (for example, acids) that cause deterioration or expansion of the sponge need to be minimized.

As described above, according to the present invention, by using a coating solution in which the above-mentioned ruthenium dioxide fine particles and the inorganic and organic ultraviolet absorbing materials are appropriately coexistent, a transparent material for effectively shielding heat rays and ultraviolet rays can be obtained. The film can be manufactured, and the existing window glass can be easily installed on site by the sponge coating method.

[0040]

Hereinafter, examples of the present invention will be described together with comparative examples. The main comparative numerical values of Examples 1 to 6 and Comparative Examples 1 to 4 are summarized in Table 1.

Example 1 Ruthenium dioxide (RuO ₂ )
An ethanol dispersion containing 15% by mass of fine particles (average particle diameter: 20 nm) was mixed and stirred with a strong dispersing machine together with a small amount of a dispersant to prepare a liquid A.

An ethanol dispersion containing 20% by mass of iron oxide hydroxide (FeOOH) fine particles (average particle size: 30 nm)
By mixing and stirring with a strong dispersing machine together with a small amount of a dispersant, a liquid B was prepared.

An ethanol dispersion containing 20% by mass of cerium dioxide (CeO ₂ ) fine particles (average particle size: 15 nm)
Liquid C was prepared by mixing and stirring with a strong dispersing machine with a small amount of dispersant.

5 g of solution A, 8 g of solution B and 40 g of solution C are mixed together with 30 g of propylene glycol monoethyl ether and 23 g of isobutyl alcohol, and a benzotriazole iso-octyl 3 as an organic ultraviolet absorber.
-(3- (2H-benzotriazol-2-yl) -5
-T-butyl-4-hydroxyphenyl) propionate (4 g) and a room temperature-curable binder (1811 manufactured by Showa Technocoat Co., Ltd.) (30 g) were added, and the mixture was sufficiently stirred and mixed.
A coating solution for shielding heat and ultraviolet rays was prepared.

The coating solution contained 0.57% by mass of RuO ₂ , 1.23% by mass of FeOOH, and 6.15% of CeO _2.
% By mass, and 3.07% by mass of an organic ultraviolet absorber.

The viscosity at 25 ° C. measured with a BL type viscometer (manufactured by Tokimec Co., Ltd.) using 20 ml of this coating solution was as follows:
It was 6.8 mPa · s (6.8 cP).

This coating solution was impregnated into a polyurethane foam sponge 4 × 4 × 15 mm bar and 3 × 10 ×
It was applied on a 15 mm soda lime glass and cured at room temperature to obtain a coating film. The time to dry to the touch was 25 minutes. Immediately after the sponge sweep, a streak-like non-uniformity was observed, but the liquid gradually leveled, and the dried film had a uniform finish without thickness unevenness.

The haze H of the coating film was measured at 0.5% using a haze meter (manufactured by Murakami Color Materials Laboratory).

The optical characteristics of the coating film were measured using a spectrophotometer (H-4000 manufactured by Hitachi, Ltd.). JISR31
According 60, the visible light transmittance (τ _v: 380-780n
m) and the solar radiation transmittance (τ _e : 280-1800 nm), and the ultraviolet transmittance (τ _UV : 280-380 nm) was calculated according to ISO9050. The visible light reflectance and the solar reflectance were also measured according to JISR3160, and the solar heat gain η and the solar shading coefficient SC were also determined.

FIG. 1 shows the optical profile of the coating film.

In the above coating film, τ _v = 65%, τ _e = 5
6%, τ _UV = 0.04%, 65% visible light transmission, τ _v -τ _e = 9%, η = 0.67, SC
It was confirmed that there was a near-infrared light shielding capability corresponding to 0.77. That is, through this coating film, 820 nm
The sun's rays are absorbed and reflected to the maximum near infrared rays,
It was found that 23% of the solar energy was blocked and 99.96% of the UV light was blocked.

The coated film was allowed to stand in a room at room temperature, and the surface hardness after one week was measured using a Tabor abrasion wheel CS12f under a load of 250 g and a change ΔT in visible light transmittance τ _v after 50 rotations and a change in haze H. Evaluation was made based on the change ΔH. ΔT = 0.
The values of 7% and ΔH = 2.4% were obtained, and it was confirmed that the coating film had sufficient practical hardness. Further, 30 days after the standing, the surface of the coating film was observed to examine whether or not there was bleed-out of the surface of the organic ultraviolet absorbent. As a result, no bleed-out was observed.

[Example 2] In a coating film using a 1.3-fold diluted solution obtained by adding isobutyl alcohol to the coating solution for shielding heat and ultraviolet rays prepared in Example 1, τ _v =
75%, τ _e = 67%, τ _UV = 0.8%, η = 0.7
5. A numerical value of SC = 0.86 was obtained, and the ability to block heat rays and ultraviolet rays was confirmed. This solution contains 0.43 RuO _2.
% By mass, FeOOH by 0.94% by mass, CeO ₂ by 4.
73% by mass and 2.36% by mass of an organic ultraviolet absorber. The viscosity of the solution at 25 ° C. is 6.4 mPa · s.
(6.4 cP).

FIG. 1 shows the optical profile of the coating film.

[Example 3] The amount of impregnating liquid into the sponge at the time of sponge coating using a solution diluted by adding isobutyl alcohol to the coating solution for heat and ultraviolet shielding prepared in Example 1, In the coating film obtained by changing the sponge pressure and the sponge sweep speed, τ _v = 70%, τ _e
= 62%, τ _UV = 0.1%, SC = 0.82, and the ability to block heat rays and ultraviolet rays was confirmed. The viscosity at 25 ° C. of the solution was 6.6 mPa · s (6.6 cP).

Example 4 A sponge-impregnating liquid amount at the time of sponge coating using a solution obtained by adding isobutyl alcohol to the coating solution for shielding heat and ultraviolet rays prepared in Example 1 and a method for coating the glass surface were used. In the coating film obtained by changing the sponge pressure and the sponge sweep speed, τ _v = 76%, τ _e
= 69%, τ _UV = 1.4%, SC = 0.88, and the ability to block heat rays and ultraviolet rays was confirmed. The viscosity of the solution at 25 ° C. was 6.1 mPa · s (6.1 cP).

Example 5 The amount of the impregnating liquid into the sponge when the sponge was coated by using a solution prepared by diluting the coating solution for heat and ultraviolet rays prepared in Example 1 with the addition of isobutyl alcohol was applied to the glass surface. In the coating film obtained by changing the sponge pressure and the sponge sweep speed, τ _v = 81%, τ _e
= 74%, τ _UV = 4.4%, SC = 0.91, and the ability to block heat rays and ultraviolet rays was confirmed. The viscosity at 25 ° C. of the solution was 5.9 mPa · s (5.9 cP).

[Example 6] 3.5 g of the above-mentioned solution A and 1 of solution B
0.5 g of propylene glycol monoethyl ether 4
0 g and 45 g of isobutyl alcohol, and further mixed with iso-octyl 3- (3
-(2H-benzotriazol-2-yl) -5-t-
Butyl-4-hydroxyphenyl) propionate 1
g and room temperature curing binder (Showa Techno Coat Co., Ltd.)
1811) was added and sufficiently stirred and mixed to prepare a coating solution for shielding heat and ultraviolet rays.

The viscosity of the coating solution at 25 ° C., 5.8 mPa
S (5.9 cP).

When this coating solution was applied by sponge coating in the same manner as in Example 1, good coating properties were obtained.
The coating film obtained by drying has a uniform finish,
The optical properties are: τ _v = 74%, τ _e = 67%, τ _UV = 17
%, SC = 0.86, and the ability to block heat rays and ultraviolet rays was confirmed.

FIG. 1 shows the optical profile of the coating film.

No bleeding was observed after 30 days.

Comparative Example 1 An isobutyl alcohol dispersion containing 40% by mass of cerium dioxide (CeO ₂ ) fine particles (average particle size: 15 nm) was mixed with a small amount of a dispersant by a strong disperser and stirred to prepare a solution D. did.

5 g of Solution A, 8 g of Solution B and 140 g of Solution D were mixed together with 30 g of propylene glycol monoethyl ether and 23 g of isobutyl alcohol, and iso-octyl 3- (3- (2H-benzotriazole-) was used as an organic ultraviolet absorbent. 6 g of 2-yl) -5-t-butyl-4-hydroxyphenyl) propionate and 30 g of a high molecular weight silicate solution as a cold curing binder
In addition, the mixture was sufficiently stirred and mixed to prepare a coating solution for shielding heat and ultraviolet rays.

The high molecular weight silicate solution is obtained by accelerating the hydrolysis and polymerization of ethyl silicate (ethyl silicate 40 manufactured by Tama Chemical Co.) with a small amount of ethanol, water and hydrochloric acid, and reducing the molecular weight in terms of polystyrene measured by gel permeation chromatography. Proceed to 100,000 and ethanol with Si
What was diluted to 15% of O ₂ solid content was used.

The viscosity of this coating solution at 25 ° C. was 25 mPa ·
s (25 cP).

This coating solution was sponge-coated in the same manner as in Example 1. However, because of the high viscosity, unevenness in density in a wet state was remarkably observed, and the unevenness in density was slightly eliminated after drying. However, it did not completely disappear. The haze of the coating film after drying was slightly high, and the Tabor strength was also slightly lowered.

[Comparative Example 2] A coating solution for shielding heat and ultraviolet rays was prepared in the same manner as in Example 1 except that the average particle size of RuO ₂ used was 72 nm. In the coating film prepared with this coating solution, the film strength was reduced and the haze H was increased to 5.2%, resulting in a cloudy film deviating from the practical range.

[Comparative Example 3] A coating solution for shielding heat and ultraviolet rays was prepared in the same manner as in Example 1 except that the average particle size of CeO ₂ used was 110 nm. In the coating film produced with this coating solution, roughness was observed on the film surface, and the haze H increased to 6.3%, resulting in a cloudy film deviating from the practical range.

Comparative Example 4 Amount of iso-octyl 3- (3- (2H-benzotriazol-2-yl) -5-tert-butyl-4-hydroxyphenyl) propionate used as an organic ultraviolet absorber Was changed to 9 g (6.67% by mass in the coating liquid) in the same manner as in Example 1 to prepare a coating liquid for heat and ultraviolet ray shielding. In the coating film prepared with this coating solution, almost 100% of the ultraviolet rays were cut, but after 3 days, the glass surface became whitish and bleeding was observed.

[0071]

[Table 1]

Example 7 In order to observe the effect of strong ultraviolet light on the coating film, an acceleration tester (Super UV tester SUV manufactured by Iwasaki Electric Co., Ltd.) using a metal halide lamp as an irradiation source was used.
-131 W).

Using the glass surface of the coating film prepared in Examples 2 to 5 as an incident surface of ultraviolet light, each sample was irradiated with an irradiation intensity of 100 mW / cm ² , a substrate temperature of 63 ° C., and a humidity of 30%.
% For 300 hours. Meanwhile, 15h, 30
After h, 60 h, 90 h, 150 h, 240 h, and 300 h, sample coupons were taken out and optical characteristics were measured.

The change of each characteristic is shown in Table 2 and FIGS.
Although the correspondence with real time is not enough, as a rough guideline compared with the results of other testing machines, 30h
Is considered about one year in sunlight.

For a test time of 300 h, τ _v of these coating films was reduced by a maximum of 1.58 points, and τ _e was a maximum of 1.
It was confirmed that there was little change in the color tone and heat ray shielding effect of the coating film with a decrease of 56 points. The τ _UV increased by 19.34% for the thin film, but increased only by 7.39% for the thick film. Even after irradiation of strong ultraviolet light for 300 hours, the ultraviolet light shielding effect of 76 to 92% was maintained as a coating film. I found out.

[0076]

[Table 2]

Example 8 In order to observe the effects of ultraviolet light and rainwater on the coating film, six samples were placed on a carbon arc sunshine weatherometer using the glass surface of the coating film prepared in Example 6 as an incident / sprinkling surface. 120 each
h (corresponding to 6 months) to 2521 h (corresponding to 10 years), and thereafter, a sample specimen was taken out, and the optical characteristics and strength were measured.

Table 3 and FIG. 5 show the change of each characteristic by the weatherometer.

For a test time of 2521 h corresponding to 10 years, τ _v decreased by 0.59 points, τ _e decreased by 0.33 points, τ _UV decreased by 0.93 points, indicating that the heat ray shielding ability and the ultraviolet ray shielding ability were reduced. It was found that all of the optical characteristics including the sample hardly changed.

The Tabor abrasion strength is the initial value Δ
In contrast to T = 0.5% and ΔH = 3.8%, ten years later, ΔT = 0.4% and ΔH = 0.0%, indicating that the strength was improved.

[0081]

[Table 3]

[0082]

As described above, according to the present invention, it is possible to apply a sponge coat directly to an existing window glass and uniformly apply the same. It is possible to form a coating film free of heat and bleed and having a long-lasting effect of shielding heat rays and ultraviolet rays in sunlight.

[Brief description of the drawings]

FIG. 1 is a graph showing transmission profiles of coating films of Examples 1, 2, and 6.

FIG. 2 is a graph showing changes in optical properties of the coating films of Examples 2 to 5 after strong UV irradiation.

FIG. 3 is a graph showing changes in optical properties of the coating films of Examples 2 to 5 after strong UV irradiation.

FIG. 4 is a graph showing changes in optical properties of the coating films of Examples 2 to 5 after strong UV irradiation.

FIG. 5 is a graph showing a change in optical characteristics of a coating film of Example 6 after a weatherometer test.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C03C 17/32 C03C 17/32 A C09D 7/12 C09D 7/12 C09K 3/00 C09K 3/00 U 105 105 (72) Inventor Hiroyuki Tanaka 3-18-5 China, Ichikawa City, Chiba Prefecture Sumitomo Metal Mining Co., Ltd. Central Research Laboratory (72) Inventor Yuko Kuno 3-18-5 China, Ichikawa City, Chiba Prefecture Sumitomo Metal Mining Co., Ltd. Central Research Laboratory (72) Inventor Taketoshi Matsuura 2-1-1, Nishi-Shinjuku, Shinjuku-ku, Tokyo NTT Advanced Technology Co., Ltd. F-term (reference) 4D075 AC49 CB07 DB13 DC01 DC12 EC02 EC54 4F100 AA17B AA23B AH02B AH03B AT00A BA02 BA07 CA07B DE01B EH46 EJ08 GB07 GB32 JA06B JL00 JN01 JN08 YY00B 4G059 AA01 AC06 AC07 FA05 FA15 FA17 FA22 FA28 FA29 FA30 FB05 4J038 CG001 DG001 DL031 DL171 HA216 JA33 JB35 JC30 KA12 KA20 MA07 MA08 MA10 MA15 NA19 NA23 NA24 PA01 PA18 PA19 PB05 PB07 PB08 PC03 PC08

Claims (3)

[Claims] 1. Ruthenium dioxide fine particles having an average particle size of 50 nm or less are contained in an amount of 0.1% by mass or more and 1% by mass or less.
1% by mass or more and 10% by mass or less of iron oxide hydroxide and / or cerium dioxide fine particles of 00 nm or less, and 1% by mass or more and 6% by mass or less of a benzophenone-based and / or benzotriazole-based organic ultraviolet absorbing material. A coating liquid for forming a transparent heat ray ultraviolet shielding film for sponge coating, characterized by comprising: 2. A normal temperature viscosity of 2 mPa · s or more and 20 mPa
2. The coating liquid for forming a transparent heat ray ultraviolet ray shielding film for sponge coating according to claim 1, wherein the coating liquid is 2 s or less (2 cP or more and 20 cP or less). 3. A transparent heat ray ultraviolet light shielding film obtained by applying the coating liquid for forming a transparent heat ray ultraviolet ray shielding film according to claim 1 or 2 to a substrate by a sponge coating method and then curing it at room temperature or hot air drying.