JPH07257922A - Hydrophobic antimony containing tin oxide, heat ray shielding coating liquid and each production thereof - Google Patents

Abstract

PURPOSE:To provide an antimony containing tin oxide capable of stably dispersing in an organic solvent, a heat ray shielding coating liquid and heat ray shielding glass and these producing methods. CONSTITUTION:The hydrophobic antimony containing tin oxide fine particle is obtained by adding a cationic surfactant or nonionic surfactant in an aq. sol of the antimony containing tin oxide fine particle to obtain a precipitate and drying the precipitate. And the heat ray shielding coating liquid is obtained by dispersing the hydrophobic antimony containing tin oxide fine particle in a silazane polymer solution. Furthermore, the heat ray shielding glass is obtained by applying the heat ray shielding coating liquid on a glass and burning.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat ray-shielding coating liquid and a heat ray-shielding glass coated with the same.
The present invention relates to a heat ray shielding glass suitable for vehicles and buildings that require high transparency and film hardness.

[0002]

2. Description of the Related Art Conventionally, as a means for obtaining a heat ray shielding coating liquid and a heat ray shielding glass, for example, in Japanese Patent Application No. 5-56021 and Japanese Patent Application No. 5-104526, a heat ray shielding film and a heat ray shielding film using tin oxide fine particles are disclosed. Shielding glass has been proposed by the inventors. According to these inventions, by using tin oxide fine particles and a siloxane compound, a heat ray shielding glass having a high visible light transmittance, an excellent heat ray shielding property, and a low price can be obtained. It is disclosed that it is suitable as a glass for use.

However, a film using a siloxane compound has a high baking temperature, and generally requires a baking temperature of 550 ° C. or higher to obtain the same abrasion resistance as glass, and the glass is deformed or baked during baking. There is a problem that the energy cost of

Therefore, the present inventors have filed Japanese Patent Application No. 5-104.
In No. 526, as a method for producing a heat ray shielding film having high film strength by low temperature firing using tin oxide fine particles and a silazane polymer, first, a heat ray shielding film is formed using an antimony-containing tin oxide (hereinafter referred to as ATO) sol. Then, a method of forming a strong heat ray-shielding film by applying a silazane polymer solution and baking it is disclosed.

However, according to this method, in order to produce a heat ray-shielding film, coating and baking must be repeated twice, which complicates the manufacturing process and the manufacturing cost is lower than that of the method used before. Although the cost is low compared to
It may be relatively expensive.

Therefore, a heat ray-shielding coating liquid which can disperse the ATO sol and the silazane polymer in the same solvent and coat and fire them on the glass at one time is conceivable. However, the ATO sol is a water dispersion system and has low polarity. When an organic solvent is mixed, coagulation occurs and the dispersibility is impaired. On the other hand, the silazane polymer shows remarkable reactivity with water and causes decomposition or gelation. There is a problem that it is impossible to use a heat ray-shielding coating liquid for producing a heat ray-shielding film having excellent shielding properties, transparency and film strength.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of these circumstances, and a heat ray shielding glass capable of easily producing a heat ray shielding glass excellent in heat ray shielding property at low cost. It is intended to provide a coating liquid and a method for producing the same.

[0008]

This object can be solved by using hydrophobic antimony-containing tin oxide fine particles as the antimony-containing tin oxide. The hydrophobic antimony-containing tin oxide fine particles are obtained by adding a cationic surfactant or a nonionic surfactant to an aqueous sol of antimony-containing tin oxide to obtain a precipitate, and then drying the precipitate. Obtainable. At this time, the addition amount of the cationic surfactant or nonionic surfactant is preferably 4 to 26% by weight with respect to the antimony-containing tin oxide.

Further, by dispersing the hydrophobic antimony-containing tin oxide fine particles in a silazane polymer solution, a heat ray shielding coating solution can be prepared. Also,
The particle diameter of the hydrophobic antimony-containing tin oxide fine particles is
It is preferably 100 nm or less. Further, the weight ratio of the hydrophobic antimony-containing tin oxide to the silazane polymer is such that the hydrophobic antimony-containing tin oxide: silazane polymer =
It is preferably 19: 1 to 1: 4.

Further, a heat ray-shielding glass can be produced using the heat ray-shielding coating liquid. Such a heat ray-shielding glass can be produced by applying the heat ray-shielding coating liquid to a part or all of the glass serving as a substrate, and then firing at 300 to 550 ° C.

[0011]

By adding a cationic surfactant or a nonionic surfactant to the aqueous sol-like ATO, the surface of the ATO is converted from hydrophilic to lipophilic and stably dispersed in an organic solvent. .

[0012]

The present invention will be described in detail below. First, the hydrophobic antimony-containing tin oxide fine particles of the present invention will be described. The surface of the hydrophobic antimony-containing tin oxide fine particles (hereinafter abbreviated as organo ATO) has lipophilicity,
Thereby, it is stably dispersed in the organic solvent.

An example of the method for producing such an organo ATO will be described below. First, ATO is made into an aqueous sol state with good dispersibility. A method for producing the ATO sol is disclosed in, for example, JP-A-2-105875, and according to this method, A having a particle size of 5 to 20 nm is used.
Although a sol in which TO particles are almost monodispersed can be obtained, the method for producing the ATO particles and the ATO sol is not limited to this, and any method can be used.

Then, a cationic surfactant or a nonionic surfactant is added to the aqueous ATO sol to obtain a precipitate. This is because by changing the surface of the ATO fine particles to lipophilic and removing 100% of water from the surface,
This is because it is possible to disperse in an organic solvent while maintaining the dispersibility.

As the cationic surfactant and nonionic surfactant, any one can be used as long as it adsorbs ATO fine particles by directing a hydrophilic group to make the particle surface lipophilic. Particularly, the cationic surfactant is preferably a primary amine salt or an alkyl quaternary ammonium salt, and the nonionic surfactant is preferably an alkylamine ethylene oxide condensate.

Examples of the primary amine salt include octylamine, decylamine, dodecylamine, tetradecylamine, octadecylamine, cocoalkylamine, beef tallowamine, hardened beef tallowalkylamine, soybean alkylamine, tetradecylamine acetate, octadecyl. Examples thereof include amine acetate.

As the alkyl quaternary ammonium salt,
Dodecyltrimethylammonium chloride, tetradecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, octadecyltrimethylammonium chloride, methyldodecylbenzyltrimethylammonium chloride, dodecyldimethylbenzylammonium chloride, tetradecyldimethylbenzylammonium chloride, octadecyldimethylbenzylammonium chloride, etc. Is mentioned.

Examples of the alkylamine ethylene oxide condensate include polyoxyethylene dodecylamine, polyoxyethylene octadecylamine, polyoxyethylene cocoalkylamine, polyoxyethylene tallow alkylamine and the like. Such nitrogen-based surfactants are suitable because they are adsorbed on the ATO surface effectively and the precipitation composition is rapid with a small amount of addition to make them lipophilic, and when the formed precipitate is dried, It is presumed that this is because it is possible to obtain the organo ATO that is extremely easy to disperse in the organic solvent without forming a lump having strong aggregation.

The addition amount of the above-mentioned cationic surfactant or nonionic surfactant can be appropriately adjusted depending on the surface area of the ATO fine particles, and is particularly 4 to 26% by weight with respect to the aqueous ATO sol, and further, Is 5 to 20% by weight
Is preferred. This is because if the amount is less than 4% by weight, the amount of the surfactant added is small and the entire surface of the ATO fine particles cannot be made lipophilic, which may result in poor dispersibility in the organic solvent. On the other hand, if it exceeds 26% by weight, not only is the amount of the surfactant added too much to be wasted, but it also causes whitening of the film when the film is formed later.

Then, the precipitate thus obtained is subjected to a treatment such as filtration or compression to remove water. At this time, the filtering and pressing methods are arbitrary, and appropriate means can be used depending on the amount of the obtained precipitate and the like. Then, the precipitate is dried. The drying temperature is preferably 160 ° C or lower. This is because the surfactant may volatilize and decompose at 160 ° C. or higher.

Organo ATO thus obtained
Immediately after production, it is in a lump form, but it can be made into a powder form by lightly crushing it.

In such an organo ATO, the ATO surface is converted from hydrophilic to lipophilic by adding a cationic surfactant or a nonionic surfactant after making ATO into an aqueous sol. Since it is obtained, it can be stably dispersed in an organic solvent.

Next, a heat ray shielding coating solution using the organo ATO will be described. This heat ray-shielding coating liquid is a coating liquid using antimony-containing tin oxide fine particles as a heat ray-shielding material.
O is dispersed in a silazane polymer solution serving as a binder.

The organo ATO has a particle size of 100 nm.
In the following, preferably 3 to 100 nm, further 5 to 50 nm
nm. This is because in order to make the heat ray-shielding film obtained by the heat ray-shielding coating liquid transparent, absorption in the visible region and little scattering are required. Since Organo ATO does not absorb visible light, transparency can be obtained by reducing scattering.
Generally, the scattering of light by particles has a particle size of about 1/2 of the wavelength.
It is known that it becomes maximum at the time of, and when it is smaller, it becomes smaller in proportion to the sixth power of the particle size. Since the wavelength of visible light is 400 to 780 nm, the particle size is about 200 to
Since the scattering becomes maximum at 390 nm and becomes smaller at 390 nm or less, the heat ray shielding film can be made transparent by setting the particle size to 100 nm or less.

The organo ATO preferably has good dispersibility when dispersed in a solvent. This is because when the particle size of the organo ATO aggregated during dispersion is 100 nm or more, a transparent coating film cannot be obtained for the same reason. Therefore, the organo ATO is in a sol state (hereinafter, organo A
It is preferably abbreviated as TO sol).

Further, the silazane polymer has the following (I)
Having a number average molecular weight represented by the structural formula of 100 to 5000
Any inorganic polymer of 0 can be used. These can be obtained, for example, by the methods disclosed in JP-A-60-145903 and JP-A-61-89230. Further, in the above structural formula, at least one of R ₁ , R ₂ , and R ₃ is a hydrogen atom, and the others are hydrogen atoms, alkyl groups, alkenyl groups, cycloalkyl groups, aryl groups, alkylsilyl groups, alkylamino groups, Represents an alkoxy group.

The weight ratio of the organo ATO to the silazane polymer is 19: 1 to 1: 4, preferably 9: 1 to 1: 3, and more preferably 4: 1 to 1: 2. This is because when the hydrophobic antimony-containing tin oxide is more than the ratio in the range of 19: 1 to 1: 4, the strength of the heat ray shielding film becomes insufficient, and conversely, when the organo ATO is small, the heat ray shielding performance deteriorates. Is.

The organic solvent used as the dispersion medium for the organo ATO and the silazane weight compound may be any solvent as long as the silazane polymer can be dissolved therein, such as aromatic hydrocarbons such as benzene, toluene and xylene, and diethyl ether. , Ethers such as dibutyl ether and tetrahydrofuran, and halogenated hydrocarbons such as dichloromethane and tetrachloromethane.

Next, a method for producing the heat ray shielding coating solution of the present invention will be described. First, antimony-containing tin oxide fine particles having a particle size of 100 nm or less are prepared, and the above-mentioned organo ATO
Organo ATO is produced in the same manner as in the production method of 1. At this time, the organo ATO is dried until the residual water content becomes 1% or less. This is because when the residual water content is 1% or more, when the following silazane polymer solution is mixed, the organo AT
This is because O aggregates, the transparency of the heat ray-shielding film produced thereby decreases, and the stability of the silazane polymer is impaired.

Then, the organo ATO is added to an organic solvent and shaken or stirred to obtain an organo ATO sol,
Then, it can be obtained by adding an arbitrary amount of the silazane polymer to the organo ATO sol. Further, in this case, an ultrasonic disperser, a homogenizer, or the like may be used in order to disperse even better.

Since such a heat ray-shielding coating liquid comprises organo ATO dispersed in a silazane polymer solution, when a heat ray-shielding film is produced using this solution,
A heat ray shielding film having excellent film strength, abrasion resistance, and transparency can be produced even with a single layer film.

Next, a heat ray shielding glass using the heat ray shielding coating liquid of the present invention will be described. This has a heat ray-shielding film formed by applying the heat ray-shielding coating liquid on the glass surface and drying it, at least on a part of the glass surface.

As the glass, soda lime glass,
Any material such as E glass, hard glass, and quartz glass can be used. Further, the glass may be transparent or opaque, but since the heat ray-shielding coating liquid of the present invention can produce a transparent heat ray-shielding film, the glass itself is also transparent. The more effective one is, the more effective it is.

In order to obtain the heat ray shielding effect, it is preferable that the difference between the visible light transmittance and the solar radiation transmittance of the heat ray shielding glass (hereinafter referred to as the solar radiation shielding effect) is 8% or more.

The thickness of the heat ray shielding film is 0.1 to
It is preferably 4 μm. This is because when the thickness is 0.1 μm or less, the film strength is reduced and a sufficient heat ray shielding effect cannot be obtained. Furthermore, even if the thickness is 4 μm or more, the heat ray shielding effect is not significantly improved, which is uneconomical. In addition, the intended use of the heat ray-shielding glass and the organo A contained in the heat ray-shielding film.
Depending on the TO amount, it may be outside the above range.

Such a heat ray-shielding glass can be obtained by applying the heat ray-shielding coating liquid to the glass by an arbitrary method such as a spin method, a dipping method, or a spray method, and then firing it. The firing temperature is preferably 300 to 550 ° C. This is because the heat ray shielding film formed at 300 ° C. or lower has poor film strength, and at 550 ° C. or higher, soda lime glass, which is mainly used as a substrate, may be deformed.

Next, a method of using the heat ray shielding glass of the present invention will be described. The heat ray shielding glass of the present invention can be used as vehicle glass. In this case, the visible light transmittance is preferably 70% or more from the viewpoint of safety. This visible light transmittance is equal to that of organo AT contained in the heat ray shielding film.
It can be adjusted by the O amount. Here, the thickness 3.
FIG. 1 shows changes in visible light transmittance and solar radiation transmittance when a heat ray shielding film was formed on 5 mm soda-lime glass. According to FIG. 1, when the amount of the organo ATO in the heat ray shielding film is 7.2 g / m ² or less, the visible light transmittance can be 70% or more. Further, from the viewpoint of the heat ray shielding effect, it can be seen from FIG. 1 that the amount of organo ATO in the heat ray shielding film is 0.7 g / m ² or more in order to make the solar radiation shielding effect 8% or more. Therefore, in order to obtain a heat ray-shielding glass having a visible light transmittance of 70% or more and a solar radiation shielding effect of 8% or more, using soda-lime glass having a thickness of 3.5 mm as the vehicle glass, the organo-glass in the heat ray-shielding film is required. Set the ATO amount to 0.
It may be 7 to 7.2 g / m ² .

It can also be used for building glass. For buildings, it often doubles as an interior,
As the glass to be the substrate, not only transparent glass but also colored transparent glass, opaque glass, glass with a beautiful pattern, etc. can be used. Furthermore, the visible light transmittance and the solar radiation shielding rate of the heat-shielding glass to be obtained are the same as those of the above-mentioned vehicle glass.
It can be arbitrary by adjusting the amount. Further, the use examples of the heat ray shielding glass of the present invention are not limited to these examples.

Such a heat ray shielding glass is manufactured by Organo A
Since it has a heat ray-shielding film formed by a heat ray-shielding coating liquid obtained by dispersing TO in a silazane polymer solution, the heat ray-shielding glass has a high visible light transmittance and a high heat ray-shielding effect. In addition, antimony-containing tin oxide that has a heat-ray shielding effect and the binder of this can be applied at one time to the silazane polymer that imparts film strength, simplifying the manufacturing process and reducing the manufacturing cost. can do. Further, regardless of the low firing temperature, it is possible to have a heat ray-shielding film having high wear resistance and high film strength, and it is possible to obtain glass suitable for vehicle glass and building glass.

(Examples) The effects of the present invention will be clarified below by showing specific examples. 6.2 parts by weight of SbCl ₃ and 6
70 parts by weight of SnCl ₄ .5H ₂ O was dissolved in 3000 parts by weight of 6N hydrochloric acid, and 25% ammonia solution was added to ₂ parts thereof.
000 parts by weight was added and reacted, and the reaction product was filtered and washed until ammonium chloride could not be detected. The reaction product-containing solution is heated to 350 ° C. in a closed container,
After holding for 5 hours, water vapor is released in the cooling process, concentrated to a solid content of 25% by weight, and aqueous ATO having a particle size of 1 to 10 nm
I got a sol.

10 parts by weight of octadecylamine as a cationic surfactant was added to 400 parts by weight of the aqueous ATO sol to obtain a coagulated precipitate. The aggregated precipitate was taken out by filtration and dried at 70 ° C. for 2 hours to obtain a surface-treated organo ATO. 100 parts by weight of the surface-treated organo ATO and 125 parts by weight of xylene were mixed and lightly stirred to give 40 parts of the organo ATO.
% Organoorgano ATO sol was obtained. This Organo A
The TO sol had good dispersibility and did not separate or precipitate even after being left for a long time. 75 parts by weight of the organo ATO sol and 100 parts by weight of a xylene solution containing 20% by weight of a silazane polymer (PHPS-1 manufactured by Tonen Corporation) were mixed with 75 parts by weight of xylene to obtain a solid content of 20% by weight.
A heat ray shielding coating liquid of was obtained.

The heat ray-shielding coating solution was applied by spin coating to soda-lime glass having a thickness of 3.5 mm while changing the number of revolutions so that the amount of organo ATO was 2.0 to 8.0 g / m ^2. Firing was performed for 1 hour at each temperature in the range of ˜550 ° C.

Table 1 shows the visible light transmittance, the solar radiation transmittance and the abrasion resistance of the heat ray shielding glass. Here, the visible light transmittance and the solar radiation transmittance were measured by the method of JIS R3106. Further, the wear resistance was shown by using a Taber wear tester, and using a CS-10F wear wheel, by changing the haze by 1,000 times wear with a load of 500 g.

Example 2 Aqueous ATO sol 4 of Example 1
10 parts by weight of dodecyldimethylbenzylammonium chloride as a cationic surfactant was added to 00 parts by weight to obtain an aggregate precipitate. The aggregated precipitate was taken out by filtration and dried at 70 ° C. for 2 hours to obtain a surface-treated organo ATO. This surface-treated organo AT
100 parts by weight of O and 125 parts by weight of xylene are mixed,
By lightly stirring, an organo ATO sol containing 40% of organo ATO was obtained. Similar to Example 1, this organo ATO sol had good dispersibility and did not separate or precipitate even after being left for a long time. This Organ AT
When a heat ray-shielding coating liquid and a heat ray-shielding glass were produced from O sol in the same manner as in Example 1, the same results as in Example 1 were obtained.

(Example 3) Aqueous ATO sol 4 of Example 1
10 parts by weight of polyoxyethylene dodecylamine as a nonionic surfactant was added to 00 parts by weight to obtain an aggregate precipitate. The aggregated precipitate was filtered off and
It was dried at 0 ° C. for 2 hours to obtain a surface-treated organo ATO. 100 parts by weight of the surface-treated organo ATO and 125 parts by weight of xylene were mixed, and the mixture was lightly stirred to give an organo AT containing 40% of the organo ATO.
O sol was obtained. This organo ATO sol also had good dispersibility as in Example 1, and did not separate or precipitate even after being left for a long time. When a heat ray-shielding coating liquid and a heat ray-shielding glass were produced from this organo ATO sol in the same manner as in Example 1, the same results as in Example 1 were obtained.

Comparative Example Organo ATO obtained in Example 1
75 parts by weight of the sol and 175 parts by weight of a toluene solution containing 11.4% by weight of polysiloxane prepared by hydrolyzing and polycondensing a silicon alkoxide are mixed to obtain a solid content of 20.
A wt% coating solution for heat ray shielding was obtained. This heat ray-shielding coating liquid is spin-coated to a thickness of 3.5 mm.
It is applied to soda lime glass at 500 ℃, 550 ℃, 5
It was baked at 80 ° C. for 1 hour to obtain a heat ray shielding glass. Table 1 shows the visible light transmittance, the solar radiation transmittance, and the abrasion resistance of this heat ray shielding glass.

[0047]

[Table 1]

As is clear from Table 1, the heat ray-shielding glass of the present invention exhibits excellent abrasion resistance even when fired at a low temperature, and further has high visible light transmittance and solar radiation transmittance. Have Further, the solar radiation shielding effect is 8% or more for all the samples of a to j, and it can be seen that the heat ray shielding effect is comparable.

[0049]

As described above, in the hydrophobic antimony-containing tin oxide fine particles of the present invention, the antimony-containing tin oxide fine particles are made into an aqueous sol, and then the cationic surfactant or the nonionic surfactant is added. By doing
Since the surface of the antimony-containing tin oxide fine particles is obtained by converting hydrophilicity to lipophilicity, the particles are stably dispersed in an organic solvent. The heat ray-shielding coating liquid of the present invention is prepared by dispersing hydrophobic antimony-containing tin oxide having a particle diameter of 100 nm or less and a residual water content of 1% or less in a silazane polymer solution. When the heat ray-shielding film is produced, a heat ray-shielding film having excellent film strength, abrasion resistance, and transparency can be produced even with a single layer. Furthermore, since the heat ray-shielding glass of the present invention has the heat ray-shielding film formed by the heat ray-shielding coating liquid, the heat ray-shielding glass has a high visible light transmittance and a high heat ray-shielding effect. In addition, antimony-containing tin oxide that has a heat-ray shielding effect and the binder of this can be applied at one time to the silazane polymer that imparts film strength, simplifying the manufacturing process and reducing the manufacturing cost. can do. Further, regardless of the low firing temperature, it is possible to have a heat ray-shielding film having high wear resistance and high film strength, and it is possible to obtain glass suitable for vehicle glass and building glass.

[Brief description of drawings]

FIG. 1: Organo ATO applied to soda-lime glass,
Organo AT in heat ray shielding glass obtained by firing
It is a graph which shows the relationship between O amount and transmittance.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tsuneo Yanagisawa 585 Tomimachi, Funabashi, Chiba Sumitomo Cement Corporation Central Research Laboratory

Claims (11)

[Claims] 1. Hydrophobic antimony-containing tin oxide fine particles having a hydrophobic particle surface. 2. A hydrophobic antimony characterized in that a cationic surfactant or a nonionic surfactant is added to an aqueous sol of antimony-containing tin oxide fine particles to obtain a precipitate, and the precipitate is dried. Method for producing contained tin oxide fine particles. 3. The hydrophobic antimony according to claim 2, wherein the amount of the cationic surfactant or nonionic surfactant added is 4 to 26% by weight based on the antimony-containing tin oxide fine particles. Method for producing contained tin oxide fine particles. 4. The method for producing tin oxide containing hydrophobic antimony according to claim 3, wherein the cationic surfactant comprises a primary amine salt or an alkyl quaternary ammonium salt. 5. The method for producing tin oxide containing hydrophobic antimony according to claim 3, wherein the nonionic surfactant comprises an alkylamine ethylene oxide condensate. 6. A heat ray-shielding coating liquid comprising hydrophobic antimony-containing tin oxide fine particles dispersed in a silazane polymer solution. 7. The heat ray shielding coating liquid according to claim 6, wherein the hydrophobic antimony-containing tin oxide fine particles have a particle diameter of 100 nm or less. 8. The hydrophobic antimony-containing tin oxide: silazane polymer weight ratio of the hydrophobic antimony-containing tin oxide: silazane polymer = 19: 1 to 1: 4. Heat ray shielding coating liquid. 9. A cationic surfactant or a nonionic surfactant is added to an aqueous sol of antimony-containing tin oxide fine particles having a particle size of 100 nm or less to obtain a precipitate, and the precipitate is dried to make it hydrophobic. Antimony containing tin oxide,
Then, this is dispersed in an organic solvent to obtain a dispersion liquid, and then
A method for producing a heat ray-shielding coating liquid, which comprises mixing a silazane polymer solution with the dispersion liquid. 10. A heat ray-shielding glass, wherein the heat ray-shielding film comprising the heat ray-shielding coating liquid according to claim 6 is formed on at least a part of glass serving as a substrate. 11. A method for producing a heat ray-shielding glass, which comprises applying the heat ray-shielding coating liquid according to claim 6 to a part or all of a glass serving as a substrate and then firing the glass at 300 to 550 ° C.