JP5544515B2 - Method for producing emulsion paint for forming weather and stain resistant film, emulsion paint and weather and stain resistant paint film - Google Patents

Method for producing emulsion paint for forming weather and stain resistant film, emulsion paint and weather and stain resistant paint film Download PDF

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JP5544515B2
JP5544515B2 JP2008331614A JP2008331614A JP5544515B2 JP 5544515 B2 JP5544515 B2 JP 5544515B2 JP 2008331614 A JP2008331614 A JP 2008331614A JP 2008331614 A JP2008331614 A JP 2008331614A JP 5544515 B2 JP5544515 B2 JP 5544515B2
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titanium oxide
coating film
weather
silicate
emulsion paint
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JP2010150434A (en
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文彦 大橋
敦 芝原
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独立行政法人産業技術総合研究所
藤倉化成株式会社
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The present invention relates to an emulsion paint for forming a weather-resistant and stain-resistant coating film comprising composite particles composed of an inorganic silicate-titanium oxide composite material and a resin component, and more particularly, utilizing a hydrothermal reaction. Composite particles and resin components composed of an inorganic silicate-titanium oxide composite material in which the surface of a substrate having a surface composed of titanium oxide is coated with an inorganic silicate with a controlled chemical composition and pore structure. DOO relates weather and stain resistance coating film and the method for producing the emulsion coating material for formation, thereby coating forming emulsion paint obtained and weather resistance, stain resistance coating comprising a composition component.

In the technical field of photocatalyst using titanium oxide as a base material, the present invention relates to composite particles and resin comprising a titanium oxide composite material in which an inorganic silicate film is coated on the surface of titanium oxide using a hydrothermal reaction. how you synthesize weather and stain resistance coating forming emulsion paint comprising a component, there is provided the coating forming emulsion paints and weather resistance and stain resistance coating.

The coating film formed from the weather-resistant and stain-resistant emulsion- forming emulsion paint synthesized by the method of the present invention is resistant to external factors such as ultraviolet rays and rainfall, stain resistance in use environment, corrosion resistance For example, harmful adsorbents, deodorizers that cause sick house syndrome, removal of malodors in living environments such as indoors and cars, and in the air. It can be used as an environmental purification material for decomposing and removing harmful substances or dirt, wastewater treatment and water purification treatment, or water sterilization and algae killing.

The present invention significantly increases the productivity of titanium oxide photocatalyst composite particles coated with a silicate having a controlled chemical composition and pore structure, and improves the weather resistance and stain resistance by incorporating the photocatalyst composite particles into a paint. The present invention provides an emulsion paint for forming a new weather and stain resistant coating film and a weather and stain resistant paint film thereof.

  Paints are usually applied to the surface of various materials, products, and parts with a film thickness of several microns to several hundreds of microns. In addition to protecting them (extending their lives), Their functions are demonstrated by giving them a color, texture, luster and glitter. The main functions of the coating are aesthetics and protection of the object. One of the most important functions is the weather resistance that keeps the aesthetics with a thin film of only a few tens of microns and protects the object to be coated from the harsh environment for a long time.

  The coating is always exposed to some form of contact with the outside world and is subject to attack (chemical / physical) by light (mainly ultraviolet rays), water (rainfall, condensation, etc.), oxygen, heat, chemicals, etc. Is in a state. The performance of the coating will be determined by how well it can withstand various attacks and stimuli of these external environmental factors.

  Therefore, tests to evaluate "weather resistance" are used outdoors, such as automobiles, civil engineering machinery, large steel structures such as bridges and storage tanks, large public buildings such as buildings and gymnasiums, It is one of the most important tests in evaluating the overall performance of all machines and structures.

  With the development of petroleum synthetic chemistry since the 1960s, as the research on resin synthesis and polymer chemistry progressed, materials with better weather resistance and durability have been developed, and technology development competition Due to the intensification of the film, a coating film having more functionality than the conventional coating film performance has been demanded.

  On the other hand, various methods for decomposing and removing organic substances using a titanium oxide photocatalyst have recently been studied. The photodecomposition of water with a titanium oxide photoelectrode is called the Honda-Fujishima effect because of the name of the discoverer. This photocatalytic reaction is expected to be used as a low environmental load chemical process using solar energy. When titanium oxide is irradiated with light, electrons having a strong reducing action and holes having a strong oxidizing action are generated, and the contacting molecular species are decomposed by the redox action.

  By utilizing such action of titanium oxide, that is, photocatalytic action, for example, organic solvents dissolved in water, environmental pollutants such as agricultural chemicals and surfactants, harmful substances and bad odors in the air are decomposed and removed. can do.

  This method can be used repeatedly only by using titanium oxide and light, and the reaction product is harmless carbon dioxide and the like, and the temperature, pH, There are few restrictions on reaction conditions such as gas atmosphere and toxicity.

  In addition, this method has an advantage that even an organic halogen compound or an organic phosphorus compound that is difficult to process by a biological treatment method can be easily decomposed and removed. This method has already been put to practical use in fields such as sterilization, antifouling, and deodorization. Further, removal of nitrogen oxides in combustion exhaust gas, decomposition of volatile harmful organic compounds in houses, purification of wastewater, etc. Application to environmental purification is being studied.

  However, in the research of decomposition and removal of organic substances by the titanium oxide photocatalyst carried out so far, in general, titanium oxide powder is used as it is as a photocatalyst, and it is difficult to recover the photocatalyst after use, There were problems such as difficulty in handling and use, and it was difficult to develop a practical technology with versatility.

  Therefore, for example, attempts have been made to use a titanium oxide photocatalyst by kneading it into a medium such as easily handled fibers or plastics. However, because of its powerful photocatalytic action, not only harmful organic substances and environmental pollutants, but also fibers and plastics themselves are decomposed and they are extremely susceptible to degradation, so titanium oxide photocatalysts are incorporated into fibers and plastics. It was impossible to use it in an oval form.

  In addition, when the titanium oxide photocatalyst is used as an antibacterial or antifungal material, there is a problem that bacteria are difficult to adhere to the photocatalyst under running water or the like, so that the effect is hardly exhibited and the efficiency is poor. At present, attempts have been made to exhibit a photocatalytic function by coating a coating containing titanium oxide, which is a photocatalyst, on a base material such as a wall material. The coating film formed by the paint has the property that dirt (organic matter) adhering to the surface can be decomposed by the photocatalyst and the hydrophilic photocatalyst is exposed on the surface of the coating film, so that the dirt is difficult to adhere. Demonstrate. Therefore, the coating film containing a photocatalyst has a self-cleaning function for removing dirt by itself.

  However, when an organic paint containing a resin component is used as a paint component, the resin component comes into contact with titanium oxide, so that the photocatalytic action causes the resin to be decomposed and the coating film to deteriorate. there were. Therefore, recently, a paint containing photocatalyst composite particles in which calcium phosphate such as apatite is coated with titanium oxide has been proposed (see, for example, Patent Documents 1 to 3).

  In these paints, calcium chloride is added to a dispersion in which titanium oxide is dispersed in a simulated body fluid in which sodium chloride, calcium chloride, potassium dihydrogen phosphate, disodium hydrogen phosphate, and the like are dissolved. Manufactures photocatalyst composite particles.

  In this type of photocatalytic composite particles, apatite does not completely cover the surface of titanium oxide, but is dispersed and deposited on the surface of titanium oxide. That is, in the photocatalyst composite particles, since the surface of titanium oxide is partially exposed, the photocatalytic function is hardly lost. In the photocatalyst composite particles, since the surface of titanium oxide is coated with apatite, the apatite serves as a spacer, and titanium oxide does not directly contact the resin component, so that the decomposition of the resin component is suppressed, and the organic paint Can be used.

  In addition, since apatite is excellent in the ability to adsorb substances such as proteins and aldehydes, the photocatalyst composite particles can adsorb substances without light, and the substances adsorbed at the time of quenching can be absorbed by light. When it is irradiated, it can be decomposed by photocatalysis.

  However, the simulated body fluid used for the production of the photocatalyst composite particles contained in the coating materials described in the prior arts such as Patent Documents 1 to 3 described above has a large excess of ionic species such as sodium ions, potassium ions, calcium ions, and chloride ions. Therefore, when the dispersion liquid in which the photocatalyst composite particles are dispersed is used as it is in the paint, the resin component may aggregate due to the influence of such coexisting ion species, resulting in poor dispersion. In order to prevent agglomeration of the resin component, the dispersion must be decanted many times, and the number of production steps increases, resulting in poor productivity.

  Further, in the method using the pseudo body fluid, the growth of apatite crystals is very slow, and the productivity is low as an industrial product manufacturing technique. Therefore, it is difficult to put it into practical use, and the photocatalyst composite particles manufactured by this method In a coating film formed of a paint containing, the resin components may aggregate and the homogeneity may be lowered. For this reason, this type of paint is not satisfactory in terms of organic matter photodegradation function and weather resistance, and there has been a strong demand in the art to develop new paints and coatings that can solve these problems.

  Further, as other prior art, various combinations of photocatalysts and other inorganic compounds have been performed. For example, a method for producing a copolymer emulsion containing an inorganic compound having photocatalytic activity (Patent Document 4) A building material (Patent Document 5) obtained by coating with a water-based emulsion paint containing a humidity-controlling inorganic powder (siliceous shale etc.) supporting titanium oxide has been proposed.

  Furthermore, titanium oxide-containing colloidal silica copolymer acrylic resin emulsion paint (Patent Document 6), aqueous emulsion paint containing tetravalent metal phosphate, divalent metal hydroxide, and photocatalyst compound as essential components (Patent Document 7). ), A vinyl-based synthetic resin emulsion paint containing titanium oxide particles partially coated with calcium phosphate (Patent Document 8), and the like.

  However, conventionally, using a hydrothermal reaction, a weather resistant / stain resistant emulsion paint containing composite particles made of a titanium oxide composite material coated with inorganic silicate and a coating film formed by the emulsion paint are prepared. The synthesis is not performed, and, for example, using a hydrothermal reaction, the titanium oxide composite particles supporting the allophene or imogolite which is a silicate polymer, and the weather resistance containing the resin component It is not known at all to synthesize a stain-resistant emulsion paint and a coating film formed by the emulsion paint.

In order to efficiently decompose and remove harmful substances in the environment by photocatalytic action, it is desirable to have a reaction in the vicinity of the catalyst surface of pollutants and a high specific surface area. For example, titanium dioxide (P25) manufactured by Degussa has a specific surface area of about 50 m 2 / g although the average particle diameter of the primary particles is about 30 nm. Need time.

  The use of solids with high specific surface area and mesopores is effective for adsorbing and supporting bulky organic molecules that contaminate the environment, and the charge distribution of the solid matrix is also used for trapping polar molecules in the atmospheric system. It is desirable to be able to control. For example, as a weathered mineral of volcanic ejecta, the silicate group produced in the earth's surface layer has a high specific surface area, a high pore volume, and a selective ion exchange capacity due to the fine structure resulting from its unique shape. Is clear.

JP 2000-1631 A Japanese Patent Laid-Open No. 2003-80078 JP 2004-58050 A JP 2002-338897 A JP 2002-235382 A JP 2002-348525 A JP 2003-20438 A JP 2008-88436 A

  Under such circumstances, in view of the above prior art, the present inventors have been able to remove bad odors, decompose and remove harmful substances or dirt in the air, wastewater treatment and water purification treatment, antibacterial and antibacterial effects by photocatalysis. We conducted extensive research with the goal of developing a method for producing emulsion paints with excellent weather resistance and stain resistance that can effectively, economically and safely purify the environment such as fungi.

As a result, the present inventors are inactive as a photocatalyst, have a property of adsorbing germs and the like, are useful as environmentally friendly materials, are porous, and have a porous structure and a controlled chemical composition and pore structure. Without impairing the photocatalytic function of the titanium oxide, the porous inorganic silicate titanium oxide composite material produced by coating the oxalate polymer around the titanium oxide is added to the resin component, The present inventors have found new knowledge that it can be applied as an emulsion paint for forming a weather-resistant and stain-resistant coating film , and have further researched to complete the present invention.

  The present invention relates to a composite particle comprising a novel titanium oxide composite material in which a porous inorganic silicate having a controlled chemical composition and pore structure is coated on the surface of titanium oxide, ie, the surface of a substrate having a titanium oxide surface. The object of the present invention is to provide a weather-resistant / stain-resistant emulsion paint containing a coating film and a coating film formed from the emulsion paint.

  The present invention relates to a composite particle comprising a novel titanium oxide composite material in which a surface of a substrate having a surface made of titanium oxide (titanium oxide surface) is coated with a porous inorganic silicate having a controlled chemical composition and pore structure. The object of the present invention is to provide a weather-resistant / stain-resistant emulsion paint containing a coating film and a coating film formed from the emulsion paint.

The present invention for solving the above-described problems comprises the following technical means.
(1) Emulsion paint for coating film formation comprising composite particles composed of an inorganic silicate-titanium oxide composite material in which a surface of a substrate having a titanium oxide surface is coated with an inorganic silicate and a resin component as composition components A method of manufacturing
1) A silicon compound aqueous solution and an aluminum compound or transition metal compound aqueous solution are mixed to prepare a precursor suspension, 2) the salt by-produced in the above step is removed, and 3) the precursor suspension is mixed. 4) A hydrothermal reaction is performed, and 4) The titanium oxide composite particles coated with the inorganic silicate are synthesized on the surface of the base material according to 1) to 3), and the titanium oxide composite particles are used as resin components. 5) The emulsion paint for weather resistance / stain resistance coating film having both organic matter decomposability and the weather resistance / stain resistance of the paint film is synthesized by mixing with 5). Adjusting to a range of 2 to 30% by mass, and adjusting the solid content ratio of the above-mentioned titanium oxide composite particles in the whole emulsion paint to a range of 1 to 20% by mass, forming a weather and stain resistant coating film, For producing emulsion paint for use.
(2) The method for producing an emulsion paint for forming a weather / stain-resistant coating film according to (1), wherein the base material is titanium oxide particles.
(3) The emulsion paint for weather and stain resistance coating film formation according to (1) above, wherein the inorganic silicate is an allophane or imogolite amorphous or quasicrystalline silicate. Manufacturing method.
(4) The weather resistant / stain resistant coating according to (1) above, wherein composite particles composed of an inorganic silicate-titanium oxide composite material are synthesized on the surface of titanium oxide whose titanium oxide is anatase. A method for producing an emulsion paint for film formation.
(5) Inorganic silicates obtained by mixing a silicon compound solution having a solution concentration of 1 mmol / l to 10000 mol / l and an aluminum compound or transition metal compound solution of 1 mmol / l to 10000 mol / l, respectively The method for producing an emulsion paint for forming a weather and stain resistant coating film according to the above (1), which contains composite particles made of a titanium oxide composite material.
(6) The molar ratio of silicon to aluminum or the transition metal compound is 0.1 to 5.0, and contains composite particles made of an inorganic silicate-titanium oxide composite material. A method for producing an emulsion paint for forming a weather and stain resistant coating film.
(7) An inorganic compound obtained by preparing a precursor suspension by simultaneously mixing an aqueous solution of a silicon compound and an aqueous solution of an aluminum compound or a transition metal compound at a rate of 1 ml to 10000 l / min, or rapidly mixing both solutions. The method for producing an emulsion paint for forming a weather-resistant / stain-resistant coating film according to (1), comprising composite particles made of a silicate-titanium oxide composite material.
(8) The weather resistance according to (6) above, comprising composite particles made of an inorganic silicate-titanium oxide composite material, obtained by adjusting the liquid property of the precursor suspension from pH 3 to pH 8. A method for producing an emulsion paint for forming a stain-resistant coating film.
(9) Composite particles made of an inorganic silicate-titanium oxide composite material obtained by adding a water-soluble or water-insoluble reagent of polyethylene glycol, polyvinyl alcohol or a surfactant as an aggregation inhibitor The manufacturing method of the weather-proof and stain-resistant coating-film formation emulsion as described in said (6) which contains.
(10) Composite particles made of an inorganic silicate-titanium oxide composite material obtained by shaking the prepared precursor suspension for 0.1 to 72 hours and then removing the salt that is a reaction byproduct The manufacturing method of the emulsion paint for weather-proof and pollution-resistant coating film formation as described in said (1) containing.
(11) An inorganic silicate-titanium oxide obtained by adding an acidic solution to the precursor suspension to adjust to a weakly acidic pH of 3 to 6 and controlling the form of the silicate produced The method for producing an emulsion paint for forming a weather resistant / stain resistant coating film according to (1) above, comprising composite particles made of a composite material.
(12) An inorganic silicate-titanium oxide composite material obtained by performing a hydrothermal reaction in a method in which the water content of the suspension does not evaporate under the conditions of a reaction temperature of 20 to 150 ° C. and a reaction time of 12 to 240 hours. The method for producing an emulsion paint for forming a weather and stain resistant coating film according to (1), comprising composite particles comprising:
(13) It is obtained by adding an alkaline aqueous solution to the suspension after completion of the reaction, adjusting the liquidity of the solution to pH 8 to 12, and aggregating and collecting the product as a gel substance. The method for producing an emulsion paint for forming a weather-resistant / stain-resistant coating film according to (1) above, comprising composite particles made of an inorganic silicate-titanium oxide composite material.
(14) Weatherable / stain-resistant coating film formation according to (1) above, comprising composite particles comprising an inorganic silicate-titanium oxide composite material having a specific surface area by nitrogen adsorption of at least 10 m 2 / g For producing emulsion paint for use.
(15) A coating film comprising, as composition components, composite particles composed of an inorganic silicate-titanium oxide composite material in which an inorganic silicate is coated on the surface of a substrate having a titanium oxide surface by a hydrothermal synthesis reaction. A forming emulsion paint,
The composite particles have a surface coated with a silicate film that is inactive as a photocatalyst, and the silicate film has pores on the surface, and the bottom of the pores is active as a photocatalyst. Inorganic silicate-titanium oxide composite particles having a porous structure in which titanium oxide is exposed and having a specific surface area by nitrogen adsorption of at least 10 m 2 / g,
The resin component is a synthetic resin emulsion,
The solid content of the emulsion paint is in the range of 2 to 30% by mass, the solid content ratio of the titanium oxide composite particles in the whole emulsion paint is in the range of 1 to 20% by mass, the organic matter decomposability and the weather resistance of the coating film. -Emulsion paint for forming weather and stain resistant coatings characterized by having both stain resistance.
(16) The weather-resistant / fouling-resistant emulsion coating composition according to (15), wherein the inorganic silicate is an allophane or imogolite amorphous or quasicrystalline silicate. .
(17) A coating film formed from the emulsion coating composition according to (15) or (16), wherein the coating film has a thickness of 1 to 20 μm. film.

Next, the present invention will be described in more detail.
The present invention relates to an emulsion for forming a weather-resistant and stain-resistant coating film containing composite particles composed of an inorganic silicate-titanium oxide composite material in which a surface of a substrate having a titanium oxide surface is coated with an inorganic silicate. a method of manufacturing a paint and weather resistance and stain resistance coating film formed by the coating forming emulsion paint, and a silicon compound solution, an aluminum compound, or a transition metal compound solution was mixed, the precursor suspension Prepare the solution, remove the salt by-produced in the above step, put the base material in the precursor suspension, and perform hydrothermal reaction to oxidize the base material surface coated with inorganic silicate Titanium composite particles are synthesized, and the obtained photocatalyst composite particles are blended in a synthetic resin emulsion as a photocatalyst component.

Further, the present invention is an emulsion paint for forming a coating film , wherein the former is an inorganic silicate on the surface of a substrate having a titanium oxide surface among the photocatalyst composite particles and the resin component constituting the emulsion paint. A composite particle comprising an inorganic silicate-titanium oxide composite material coated with a hydrothermal synthesis reaction, the composite particle having a surface coated with an inert silicate film as a photocatalyst, The acid salt film has pores on the surface, and the bottom of the pores has a porous structure in which active titanium oxide as a photocatalyst is exposed, and the specific surface area due to nitrogen adsorption is at least 10 m 2 / g der is, the latter is characterized in a synthetic resin emulsion der Rukoto. Furthermore, the present invention is a weather and stain resistant coating film formed from the above-mentioned emulsion paint for forming a coating film, wherein the thickness of the coating film is 1 to 20 μm.

The composite particles contained in the emulsion paint for forming a weather-resistant and stain-resistant coating film comprising the composite particles comprising the inorganic silicate-titanium oxide composite material of the present invention and the resin component are the starting materials for coating titanium oxide. As a raw material, a silicon compound, an aluminum compound, or a transition metal compound is used. The reagent used as the silicon source may be monosilicic acid, and specifically, for example, sodium orthosilicate, alkyl orthosilicate, sodium metasilicate, amorphous colloidal silicon dioxide (aerosil, etc.) and the like are suitable. It is mentioned as a thing.

  These silicic acid compounds can be used alone or in combination of two or more. The aluminum source to be bonded to the silicate molecular aggregate may be aluminum ions. Specifically, for example, aluminum such as aluminum chloride, aluminum nitrate, sodium aluminate, aluminum hydroxide, aluminum isopropoxide, etc. Aluminum compounds such as alkyl compounds are preferred.

  Moreover, as a transition metal compound source, those ions may be used, for example, transition metal compounds such as vanadium, iron, tungsten, titanium, cobalt, nickel, copper, zirconium, for example, their chlorides, sulfides, Suitable examples include hydroxides, nitrates, and organic metal salts.

  These aluminum compounds or transition metal compounds can be used alone or in combination of two or more. These silicon source, aluminum source, or transition metal source are not limited to the above-mentioned compounds, and can be used in the same manner as long as they have the same effect.

  In the present invention, titanium oxide or at least a substrate (supported) having a surface made of titanium oxide (titanium oxide surface) is used. The substrate is preferably exemplified by titanium oxide particles, but is not limited thereto, and at least, if it is a substrate having titanium oxide on the surface, it can be used similarly. it can. The titanium oxide particles as the carrier used in the present invention are preferably anatase in the crystal form of titanium oxide from the viewpoint of high performance as a photocatalyst.

  Titanium oxides that are rutile, brookite, or amorphous are less preferred because of their low activity as photocatalysts, but these can also be used. The particle size of the titanium oxide particles may be any size, but if it is premised on kneading into organic fibers, plastics, etc., a particle size of submicron is preferable.

  These starting materials for coating titanium oxide particles are dissolved in water, an aqueous silicon compound solution having a concentration of 1 mmol / l to 10000 mol / l, an aluminum compound having a concentration of 1 mmol / l to 10000 mol / l, or vanadium, One or more aqueous solutions of transition metal compounds such as iron, tungsten, titanium, cobalt, nickel, copper, and zirconium are prepared.

  These solutions are mixed simultaneously at a rate of 1 ml to 10000 l per minute, or both solutions are rapidly mixed to prepare a precursor suspension. At this time, the molar ratio of silicon / aluminum or the transition metal compound is desirably about 0.1 to 5.0, and the pore structure is controlled by controlling the chemical composition. When the molar ratio is less than 0.1, boehmite or gibbsite is produced as a by-product, and when it exceeds 5.0, amorphous silica is produced in a large amount as a by-product.

  Further, the liquid property of the precursor suspension is preferably about weakly acidic to near neutral (pH 3 to pH 8), preferably about pH 6 to 8. For the purpose of controlling the composition, when the pH of the precursor suspension deviates significantly from the above range, hydrochloric acid, nitric acid, and sulfuric acid are calculated in advance in the transition metal compound solution as acid components in order to adjust the liquidity. It is also effective to add an alkali component such as sodium hydroxide, potassium hydroxide, calcium hydroxide or the like to the silicon compound solution in advance as an alkali component.

  At this time, a water-soluble or water-insoluble reagent such as polyethylene glycol, polyvinyl alcohol, or a surfactant may be added as an aggregation inhibitor. Thus, after mixing the silicon compound solution with the aluminum / transition metal solution, if the pH is in a weakly acidic region, the alkaline solution is dropped at a rate of 0.1 to 5 ml / min, and the pH is neutral. It adjusts so that it may become near, and produces | generates a precursor.

  At this time, examples of the alkaline solution dropped in the precursor generation process include sodium hydroxide, potassium hydroxide, calcium hydroxide, and aqueous ammonia. Of course, even when the liquidity of the solution is in the region of pH 6.5 to 8 in the vicinity of neutrality in the mixing stage, the precursor is generated.

  The obtained precursor suspension is shaken at room temperature for about 0.1 to 72 hours, and then the salt as a reaction byproduct is removed. The removal method is not particularly limited, but can be preferably performed by, for example, ultrafiltration, separation with a centrifuge, or the like. After desalting, add the same amount of pure water as the amount removed and disperse well.

  At this time, if necessary, an acidic solution is added to the precursor suspension to control the form of silicate produced, and a weakly acidic solution with a pH of 3 to 6, preferably Adjust to weak acidity so that the pH is around 3.5 to 4.5. At this time, examples of the acidic solution used include hydrochloric acid, sulfuric acid, nitric acid, acetic acid, and perchloric acid.

The manufacturing method of the composite particle which comprises the emulsion paint for coating-film formation of this invention uses the hydrothermal reaction for the base material by which the surface is covered with the titanium oxide, using the said silicate precursor, A porous silicate having a controlled chemical composition and pore structure is formed on the surface.

  Titanium oxide particles are immersed in a precursor suspension prepared from a starting solution of a predetermined concentration and reacted by heating at a predetermined temperature. The reaction temperature range is 20 to 150 ° C., and the reaction time is about 12 to 240 hours. At this time, heat aging may be performed in such a manner that the water content of the suspension does not evaporate. For example, a sealed container such as an autoclave, a mantle heater with a cooling pipe, or the like can be used as the reaction apparatus. The reaction conditions are preferably about 100 ° C. and about 48 hours.

  After completion of the reaction, the obtained product is washed with pure water several times as it is, or dried to synthesize titanium oxide composite particles coated with silicate. Since the obtained product is an inorganic compound, it has high heat resistance and can be dried under relatively severe conditions. As drying conditions, a temperature of 40 to 100 ° C. is suitable under normal pressure.

  In this case, by adding an alkaline aqueous solution to the suspension after completion of the reaction, the liquid property of the solution may be adjusted to about pH 8 to 12, and the product may be aggregated and collected as a gel substance. Examples of the alkaline aqueous solution used at this time include sodium hydroxide, potassium hydroxide, calcium hydroxide, and aqueous ammonia. Furthermore, the gel-like product aggregated with the alkaline solution can be recovered using a centrifuge or a semipermeable membrane.

  When a coagulation inhibitor is added, after completion of drying, it is extracted and removed with an organic solvent such as methanol, ethanol, acetone, toluene, xylene, benzene or the like at a temperature of 200 ° C. or lower, or in air 300 By performing the heat treatment at ˜600 ° C. and holding time of 1 to 8 hours, a titanium oxide composite material coated with silicate can be obtained.

  In the present invention, the inorganic silicate preferably includes amorphous or quasicrystalline materials of allophane, imogolite and the like. Accordingly, titanium oxide composite particles coated with spherical or tubular allophane or imogolite can be synthesized and provided.

By the above method, the specific surface area is 10 m 2 / g or more, and the physical properties of the coating film are changed by controlling the reaction conditions and the ratio of the silicon compound to be coated and other metal element compounds. Titanium oxide composite particles coated with an acid salt can be synthesized.

  As an example of the method and conditions for supporting allophane as the inorganic silicate, for example, a 100 mmol / l sodium orthosilicate solution and a 100 mmol / l aluminum chloride aqueous solution are prepared. Each is weighed so that the Si / Al ratio is 0.75, and the sodium orthosilicate solution is added to the aluminum chloride solution.

  The liquid property of the mixed solution at this time is desirably about pH 4 to 7, and the mixture is sufficiently stirred to produce a precursor suspension. In order to control the liquidity after mixing, an inorganic acid aqueous solution or an inorganic base aqueous solution may be added in advance. When the liquidity shifts to the acidic side, the precursor suspension changes to a transparent solution. Thereafter, the sodium hydroxide solution is slowly added at about 1 ml / min to adjust the liquidity to pH 6-7. When adjusted to near, a precursor is formed.

  Simultaneously with the generation of the precursor, sodium chloride is formed as a by-product, which is removed by centrifugation or the like, and the precursor is washed. Titanium oxide composite particles coated with allophane by adding 0.1 g of titanium oxide powder to 100 ml of a suspension with a precursor concentration of 10 mmol / l and performing a hydrothermal reaction at 100 ° C. for 48 hours using an autoclave. A powder is obtained.

  Next, as an example of a method and conditions for supporting imogolite as an inorganic silicate, for example, a 100 mmol / l sodium orthosilicate solution and a 100 mmol / l aluminum chloride aqueous solution are prepared, and the Si / Al ratio is The sodium orthosilicate solution is added to the aluminum chloride solution. The liquid property of the mixed solution at this time is desirably about pH 4 to 7, and the mixture is sufficiently stirred to produce a precursor suspension.

  In order to control the liquidity after mixing, an inorganic acid aqueous solution or an inorganic base aqueous solution may be added in advance. When the liquidity shifts to the acidic side, the precursor suspension changes to a transparent solution. Thereafter, sodium hydroxide solution is slowly added at about 1 ml / min, and the liquidity is adjusted to around pH 6. When adjusted, a precursor is produced. Simultaneously with the generation of the precursor, sodium chloride is by-produced, and is removed by centrifugation or the like to wash the precursor.

  0.1 g of titanium oxide powder is added to 100 ml of a suspension with a precursor concentration of 20 mmol / l, and then hydrochloric acid is added to adjust the liquidity so that the pH becomes 4. A titanium oxide composite particle powder coated with imogolite is obtained by performing a hydrothermal reaction at 100 ° C. for 48 hours using an autoclave. For both allophane and imogolite, the thickness of the coating film is controlled by the starting inorganic solution concentration and the reaction precursor concentration.

  Inorganic silicate-titanium oxide composite particles (FIG. 1) in which allophane is supported on the surface of titanium oxide and inorganic silicate-titanium oxide in which imogolite is supported on the surface of titanium oxide by the above method and conditions. Composite particles (FIG. 2) are synthesized.

  In the case of allophane, it was confirmed that aggregated spherical allophane particles aggregates were attached to the titanium oxide surface, and in the case of imogolite, a bearded aggregate with aggregated fiber bundles attached to the titanium oxide surface. It is confirmed that it is doing.

The physicochemical properties of these products are shown below. The specific surface area by the BET method and the average pore diameter by the HK method are about 200 m 2 / g and about 1 nm, respectively, and the base material titanium oxide is coated with about 10% by weight of allophane or imogolite. The material that is being produced. In X-ray diffraction, a characteristic peak is observed on the anatase peak, a broad peak in the case of allophane, and a lower angle side in the case of imogolite.

In addition, the composite particles constituting the emulsion paint for forming a weather-resistant / stain-resistant coating film of the present invention may have, for example, platinum, rhodium, ruthenium, inside the skeleton of the silicate film coated with titanium oxide, or on the film surface. It is possible to support metals such as palladium, silver, copper, and zinc, thereby further increasing the oxidative decomposition rate of the chemical substance and increasing the bactericidal and algicidal action.

Titanium oxide composite particles constituting the emulsion paint for forming a weather-resistant / stain-resistant coating film of the present invention, the porous property, film thickness, and shape of the silicate compound on the surface, the composition and temperature of the precursor, It can be controlled by changing the immersion time. When the content of silicon or other metal compounds is lowered, the reaction temperature is lowered, or the time is shortened, domain-like silicate is formed on the surface of the substrate, A thin film is formed. By increasing the content of silicon and other metal compounds or increasing the reaction temperature, the silicate film thickness can be increased.

The titanium oxide composite particles constituting the emulsion paint for weather and stain resistant coating film formation of the present invention thus prepared are coated on the surface with an inert silicate film as a photocatalyst. Since the membrane has an action of adsorbing proteins, amino acids, bacteria, viruses and the like, the surface silicate membrane can adsorb bacteria and the like in water and air. The composite material has a porous structure in which the silicate film has pores on the surface and titanium oxide active as a photocatalyst is exposed at the bottom of the pores. doing.

  Therefore, the exposed portion is irradiated with artificial light, sunlight, or the like from a fluorescent lamp, an incandescent lamp, a black light, a UV lamp, a mercury lamp, a xenon lamp, a halogen lamp, a metal halide lamp, or the like. And, by the redox action of electrons and holes generated in titanium oxide by light irradiation, the silicate film quickly and continuously decomposes adsorbed proteins, amino acids, bacteria, viruses, etc. Can be removed.

In addition, the titanium oxide composite particles constituting the emulsion paint for forming a weather resistant / stain resistant coating film of the present invention are used, for example, as an environmental purification material. When the environmental purification material is used by being kneaded in a medium such as fiber or resin, the portion in contact with the organic compound material is a ceramic that is inactive as a photocatalyst, and therefore the organic compound is decomposed. There is nothing.

  And this environmental purification material is a bad odor substance, harmful substances in the air such as toluene, xylene, ethyl acetate, paradichlorobenzene, nitrogen oxide, sulfur oxide, or organic solvents and agricultural chemicals dissolved in water, Adsorbs organic compounds that pollute the environment, and is formed into titanium oxide by irradiation with artificial light or sunlight from fluorescent lamps, incandescent lamps, black lights, UV lamps, mercury lamps, xenon lamps, xenon lamps, halogen lamps, metal halide lamps, etc. It can be decomposed and removed rapidly and continuously by the redox action of the electrons and holes.

  Moreover, this environmental purification material can be used at low cost, energy saving, and maintenance-free simply by irradiating light. And, when the one that supports platinum or rhodium, ruthenium, palladium, silver, copper, iron, zinc metal is used for the internal skeleton of the silicate coated on the titanium oxide particles, In addition, the effect of purifying the environment such as the effect of decomposing and removing organic compounds and the antibacterial and antifungal effect are further increased.

  Examples of the medium for the environmental purification material according to the present invention include polyethylene, nylon, polyvinyl chloride, polyvinylidene chloride, polyester, polypropylene, polyethylene oxide, polyethylene glycol, polyethylene terephthalate, silicone resin, polyvinyl alcohol, vinyl acetal resin, and polyacetate. , ABS resin, epoxy resin, vinyl acetate resin, cellulose, cellulose derivative, polyamide, polyurethane, polycarbonate, polystyrene, urea resin, fluorine resin, polyvinylidene fluoride, phenol resin, celluloid, chitin, starch sheet, etc. Fibers, plastics, or copolymers thereof are applicable.

Here, the resin component used for the weather-resistant and stain-resistant coating film-forming emulsion paint containing the composite particles composed of the inorganic silicate-titanium oxide composite material and the resin component of the present invention will be described. The resin component used in the present invention is not particularly limited as long as it contains a water-based organic paint. Examples thereof include synthetic resin emulsions such as acrylic resins, silicone resins, acrylic silicone resins, epoxy resins, vinyl acetate resins, polyurethane resins, polystyrene resins, and fluororesins. Of these, an acrylic silicone resin emulsion is preferred.

  In addition, 1-60 mass% is preferable and, as for content of the silicone component in an acrylic silicone resin, 5-40 mass% is more preferable. When the silicone component is small, the resin is easily decomposed by the photocatalyst composite particles described above. On the other hand, when there are too many silicone components, when the obtained emulsion paint is applied repeatedly, the paint hardly adheres to the previously formed coating film, and the newly formed coating film tends to break.

Photocatalyst composite particles, in solid content ratio of the total emulsion paint, Ru 1-20% by mass. More preferably, it is 2-15 mass%, More preferably, it is 3-10 mass%. If it is less than this range, the photocatalyst composite particles in the coating film are reduced, so that the photocatalytic effect is reduced. On the other hand, if it is more than this range, the weather resistance of the coating film is lowered.

Furthermore, the solid content of the emulsion paint, Ru 2-30% by mass. More preferably, it is 2-20 mass%, More preferably, it is 3-10 mass%. By making the solid content of the emulsion paint within the above range, the film thickness of the coating film to be formed becomes uniform, which is desirable.

  In addition, within the range which does not deviate from the meaning of this invention, you may use film forming adjuvants, such as a butyl cellosolve, a butyl carbitol, a triethylene glycol, a texanol, in a coating material as needed. In addition, additives such as antifoaming agents, thickeners, freezing stabilizers, wetting agents, pigments, water-soluble resins, penetration aids, UV absorbers, and antioxidants are blended into the paint as necessary. May be.

  Application of the emulsion paint obtained in this manner to the object to be coated can be performed by usual methods and means such as brushes, rollers, air sprays, airless sprays, and the like. Moreover, it is preferable to make the film thickness of the coating film formed thin so that the expansion and contraction of the material of the coating object may be followed. The thickness of the coating film is preferably 1 to 20 μm, more preferably 1 to 10 μm, and still more preferably 2 to 8 μm. When the film thickness falls within the above range, a mottled coating film is prevented from being formed, and a coating film having a uniform film thickness can be obtained. Furthermore, in order to make the film thickness uniform, it is preferable to apply the emulsion paint a plurality of times.

According to the method for producing an emulsion paint for forming a weather and stain resistant coating film according to the present invention, photocatalyst composite particles can be easily produced. In addition, aggregation of the resin component is suppressed, and the storage stability is excellent. In addition, the coating film formed from the emulsion paint is very unlikely to be yellowed or deteriorated due to adhesion of oil or moisture, and excellent durability and aesthetic retention can be obtained. Furthermore, even if it is an organic coating material, since a resin component prevents direct contact with a titanium oxide, a coating film is stable.

The present invention relates to a method for producing an emulsion paint for forming a weather-resistant and stain-resistant coating film comprising composite particles made of a titanium oxide composite material coated with a silicate and a resin component, and a coating film obtained therefrom. a weather and stain resistant coating film formed from the emulsion paint and the emulsion paints, acid titanium composite particles, the silicate precursor suspension, can be prepared by introducing the substrate Yes, by changing the composition, reaction temperature, and time of the silicate precursor suspension at this time, it is possible to control the size of the surface pore diameter, the density of the pore distribution, and the like . Acid titanium composite silicate Sanshiomaku covering titanium oxide on the surface of the substrate is porous, controlled silicate domain of chemical composition and pore structure, or through voids of the pores, the substrate surface Since the titanium oxide is irradiated with light, the titanium oxide composite material can provide a photocatalytic action almost the same as that not covered with the silicate film.

Further, since the silicate film has a property of adsorbing contaminants such as bacteria, the adsorbed volatile organic compound can be reliably and effectively decomposed and removed by the photocatalytic action. Is possible. INDUSTRIAL APPLICABILITY According to the present invention, the surface of titanium oxide can be coated with silicate in a simple process, and the productivity of photocatalyst composite particles is enhanced and the weather- and stain-resistant coating film forming coating material containing the photocatalyst composite particles is provided. Of emulsion coatings that can improve the organic photodecomposition function and weather resistance / contamination resistance of coatings and coating films, emulsion coating compositions for coating formation obtained therefrom, and weather resistance / stain resistance coatings formed from the emulsion coatings A membrane can be provided.

Since the coating film formed from the emulsion paint for forming a weather and stain resistant coating film according to the present invention has excellent water resistance, heat resistance and corrosion resistance inherent to the inorganic compound of the added titanium oxide composite particles. Decomposing and removing harmful substances in the air, such as bad odors and cigarette smoke, NOx and SOx, decomposing and removing organic compounds dissolved in water and organic compounds such as agricultural chemicals, wastewater treatment and water purification Use humidity control materials that autonomously control the humidity of living environments such as catalyst carriers, living rooms and cars, etc., and its unique shape, such as treatment, prevention of dirt, antibacterial and antifungal, prevention of hospital infection due to MRSA, etc. It can be used in a wide range of industrial fields, such as microcapsules for drugs and filters for water purification.

In addition, the coating film formed from the weather-resistant / stain-resistant coating film-forming emulsion paint of the present invention is extremely effective for environmental purification, and the titanium oxide is also used in paints, cosmetics, toothpastes, etc. It is also recognized as a food additive and is economical because it is non-toxic and safe, inexpensive and excellent in weather resistance and durability.

Furthermore, since the silicate film is inactive as a photocatalyst, even when the titanium oxide composite material is added to a medium such as organic fiber or plastics by kneading or the like, the medium is deteriorated. The photocatalytic effect can be maintained for a long time. In the present invention, since the silicate-supported photocatalyst composite particles can be produced with high productivity by a simple technique, the present invention is an emulsion for forming a weather-resistant / stain-resistant coating film containing the photocatalyst particle composite. The present invention is useful for providing a new technique for producing an emulsion paint for forming a coating film, which can produce a paint with a simple process and high productivity.

The present invention has the following effects.
(1) The surface of a base material having a surface made of titanium oxide contains composite particles made of a novel inorganic silicate-titanium oxide composite material coated with an inorganic silicate such as allophane or imogolite. It is possible to provide an emulsion paint for forming a weather and stain resistant coating film .
(2) Since the silicate covering the surface is porous, the titanium oxide is exposed at the bottom of the pores, and in this part, the weather resistance containing titanium oxide composite particles in which the titanium oxide is irradiated with light. It is possible to provide an emulsion paint for forming a stain- and stain-resistant coating film .
(3) Since the above silicate is inactive as a photocatalyst, the photocatalyst composite particles coated with porous inorganic silicate on the surface of titanium oxide are blended into the paint, thereby making it possible to suppress deterioration of the paint components. In addition, a paint for forming a weather resistant / stain resistant emulsion coating film can be provided.
(4) According to the present invention, the surface of titanium oxide can be coated with silicate in a simple process, and the productivity of the photocatalyst composite particles is enhanced, and the organic matter light of the paint or coating film containing the photocatalyst composite particles It is possible to provide a method for producing an emulsion paint for forming a weather and stain resistant coating film that can improve the decomposition function and weather resistance.
(5) A coating film excellent in weather resistance and stain resistance formed from the emulsion paint obtained from the emulsion paint can be provided.
(6) Due to the redox action of electrons and holes generated by light irradiation, bad odors and harmful substances in the air, or organic compounds that pollute the environment such as organic solvents and agricultural chemicals dissolved in water, It is possible to produce and provide a novel weather and stain resistant emulsion coating composition having a function of easily decomposing and removing.
(7) Since silicate has the property of adsorbing bacteria and the like, the adsorbed bacteria and others are killed and decomposed reliably and efficiently by the strong oxidizing power generated in titanium oxide by light irradiation. be able to.
(8) Since the novel titanium oxide composite particles coated with a porous inorganic silicate serve as a paint filler, the storage stability is good and an excellent photocatalytic activity can be exhibited.

Next, the present invention will be specifically described with reference to examples. However, the present invention is not limited to the following examples. Examples 1 to 13 below show production examples of photocatalyst composite particles constituting the emulsion paint for forming a coating film of the present invention, and Example 14 is an example of the emulsion paint for coating film formation of the present invention. Is shown.

(Production of photocatalytic composite particles 1)
Sodium metasilicate is dissolved in deionized water to prepare 38.46 ml of a 100 mmol / l sodium metasilicate aqueous solution. To this aqueous solution, 7.5 ml of 1 mol / l sodium hydroxide aqueous solution is added, and sodium metasilicate / hydroxide is added. A sodium mixed aqueous solution was prepared. Separately, aluminum chloride was dissolved in deionized water to prepare 50 ml of a 100 mmol / l aluminum chloride aqueous solution.

  Next, the sodium metasilicate / sodium hydroxide mixed aqueous solution was added to the aluminum chloride aqueous solution and stirred at room temperature for 1 hour to obtain a precursor suspension. The silicon / aluminum ratio at this time was 0.75. In order to remove sodium chloride formed as a by-product during the production of this precursor, it was thoroughly washed with deionized water using a centrifuge. The resulting precursor was dispersed in 1000 ml of deionized water.

  To this precursor suspension, 1 g of titanium dioxide (anatase) base material was added, and after sufficient stirring, this suspension was sealed in a Teflon (registered trademark) container and heated at 100 ° C. for 48 hours. The hydrothermal reaction was performed. After completion of the reaction, the substrate was thoroughly washed with a centrifuge. This is to remove the aluminum silicate that could not be bonded to the surface of the base material, and the titanium dioxide base material and the produced aluminum silicate were used by utilizing their specific gravity difference, This is for separation and purification by centrifugation. Thereafter, this was dried in an electric dryer at 40 ° C. and normal pressure to obtain titanium dioxide composite particles coated with silicate.

The titanium dioxide composite particles coated with silicate thus obtained were confirmed to have a substrate anatase peak from the X-ray diffraction pattern, and at the same time, the broad characterization of the amorphous silicate component. A peak was also confirmed around 10 °. This material had a specific surface area of about 200 m 2 / g by nitrogen adsorption, an average pore diameter of about 1 nm, and a pore volume in the meso region of about 0.06 ml / g.

Further, as a result of chemical composition analysis by fluorescent X-ray analysis, this material was TiO 2 : 91.9% by mass, Al 2 O 3 : 3.64% by mass, SiO 2 : 3.51% by mass, and 10% by mass. It was suggested that about% aluminum silicate was coated on the titanium dioxide substrate. Furthermore, observation by a field emission scanning electron microscope (FE-SEM) confirmed that massive spherical allophane particle aggregates adhered to the titanium oxide surface (FIG. 1).

(Production of photocatalyst composite particles 2)
125 ml each of 100 mmol / l sodium orthosilicate aqueous solution and 150 mmol / l aluminum chloride aqueous solution were weighed. A sodium orthosilicate aqueous solution was added to the aluminum chloride aqueous solution, and the mixture was sufficiently stirred at room temperature. While stirring this, 1 mol / l sodium hydroxide was added at a rate of 1 ml / min until the liquid reached pH 6. The produced precursor was washed with deionized water by a centrifuge and dispersed in a 1000 ml autoclave so that the precursor concentration was 20 mmol / l.

  To this precursor suspension, 1.0 g of titanium dioxide (anatase) base material was added, and after sufficiently stirring, a 5 mol / l hydrochloric acid aqueous solution was added until the pH reached about 4. After stirring, the mixture was sealed in a Teflon (registered trademark) container and heated at 100 ° C. for 48 hours to perform a hydrothermal reaction. After completion of the reaction, ammonia was added to increase the liquidity to about pH 10, and the produced imogolite was gelled and aggregated.

  A washing treatment by centrifugation using deionized water was performed to remove imogolite that could not be bonded to the substrate surface. Then, this was dried at 40 ° C. and normal pressure using an electric dryer to obtain titanium dioxide composite particles coated with imogolite. By FE-SEM observation, it was confirmed that a beard-like lump with aggregated imogolite fiber bundles adhered to the titanium oxide surface (FIG. 2).

(Production of photocatalytic composite particles 3)
Sodium orthosilicate is dissolved in deionized water to prepare 50 ml of a 100 mmol / l sodium orthosilicate aqueous solution. To this aqueous solution, 10 ml of a 1 mol / l sodium hydroxide aqueous solution is added, and a sodium orthosilicate / sodium hydroxide mixed aqueous solution is added. Prepared. Separately, aluminum chloride was dissolved in deionized water to prepare 100 ml of a 100 mmol / l aluminum chloride aqueous solution. Next, the sodium orthosilicate / sodium hydroxide mixed aqueous solution was added to this aluminum chloride aqueous solution and stirred at room temperature for 1 hour to obtain a precursor suspension. The silicon / aluminum ratio at this time was 0.50. In order to remove sodium chloride formed as a by-product during the production of this precursor, it was thoroughly washed with deionized water using a centrifuge. The resulting precursor was dispersed in 200 ml deionized water.

  To this precursor suspension, 0.2 g of titanium dioxide (anatase) base material was added, and after sufficient stirring, this suspension was sealed in a Teflon (registered trademark) container, and at 48C, 48 ° C. Hydrothermal reaction was performed by heating for a period of time. After completion of the reaction, the substrate was thoroughly washed with a centrifuge. This is to remove the aluminum silicate that could not be bonded to the surface of the base material, and the titanium dioxide base material and the produced aluminum silicate were used by utilizing their specific gravity difference, This is for separation and purification by centrifugation. Then, this was dried at 40 ° C. and normal pressure in an electric dryer to obtain titanium dioxide composite particles coated with silicate.

In the silicate-coated titanium dioxide composite particles obtained in this manner, the base anatase peak was confirmed from the X-ray diffraction pattern, and at the same time, a broad peak characteristic of the amorphous silicate component was observed. Was also confirmed. This material had a BET specific surface area of 211 m 2 / g by nitrogen adsorption, an average pore diameter of 8.28 nm, and a micro / meso region pore volume of 0.32 cm 3 / g. Further, as a result of chemical composition analysis by fluorescent X-ray analysis, this material has a TiO 2 content of 42.8% by mass, and an aluminum silicate of about 60% by mass is a titanium dioxide base material. It was suggested that it was coated.

(Production of photocatalytic composite particles 4)
Sodium orthosilicate is dissolved in deionized water to prepare 55 ml of a 100 mmol / l sodium orthosilicate aqueous solution. To this aqueous solution, 8 ml of a 1 mol / l sodium hydroxide aqueous solution is added, and a sodium orthosilicate / sodium hydroxide mixed aqueous solution is added. Prepared. Separately, aluminum chloride was dissolved in deionized water to prepare 100 ml of a 100 mmol / l aluminum chloride aqueous solution. Next, the sodium orthosilicate / sodium hydroxide mixed aqueous solution was added to this aluminum chloride aqueous solution and stirred at room temperature for 1 hour to obtain a precursor suspension. The silicon / aluminum ratio at this time was 0.55. In order to remove sodium chloride formed as a by-product during the production of this precursor, it was thoroughly washed with deionized water using a centrifuge. The resulting precursor was dispersed in 200 ml deionized water.

  To this precursor suspension, 0.2 g of titanium dioxide (anatase) base material was added, and after sufficient stirring, this suspension was sealed in a Teflon (registered trademark) container, and at 48C, 48 ° C. Hydrothermal reaction was performed by heating for a period of time. After completion of the reaction, the substrate was thoroughly washed with a centrifuge. This is to remove the aluminum silicate that could not be bonded to the surface of the base material, and the titanium dioxide base material and the produced aluminum silicate were used by utilizing their specific gravity difference, This is for separation and purification by centrifugation. Then, this was dried at 40 ° C. and normal pressure in an electric dryer to obtain titanium dioxide composite particles coated with silicate.

In the silicate-coated titanium dioxide composite particles obtained in this manner, the base anatase peak was confirmed from the X-ray diffraction pattern, and at the same time, a broad peak characteristic of the amorphous silicate component was observed. Was also confirmed. This material had a BET specific surface area of 165 m 2 / g by nitrogen adsorption, an average pore diameter of 11.14 nm, and a micro / meso region pore volume of 0.18 cm 3 / g. Further, as a result of chemical composition analysis by fluorescent X-ray analysis, this material has a TiO 2 content of 55.3% by mass, and an aluminum silicate having a weight ratio of about 45% by mass is a titanium dioxide base material. It was suggested that it was coated.

(Production of photocatalyst composite particles 5)
Sodium orthosilicate is dissolved in deionized water to prepare 60 ml of a 100 mmol / l sodium orthosilicate aqueous solution. To this aqueous solution is added 6 ml of a 1 mol / l sodium hydroxide aqueous solution, and a sodium orthosilicate / sodium hydroxide mixed aqueous solution is added. Prepared. Separately, aluminum chloride was dissolved in deionized water to prepare 100 ml of a 100 mmol / l aluminum chloride aqueous solution. Next, the sodium orthosilicate / sodium hydroxide mixed aqueous solution was added to this aluminum chloride aqueous solution and stirred at room temperature for 1 hour to obtain a precursor suspension. The silicon / aluminum ratio at this time was 0.60. In order to remove sodium chloride formed as a by-product during the production of this precursor, it was thoroughly washed with deionized water using a centrifuge. The resulting precursor was dispersed in 200 ml deionized water.

  To this precursor suspension, 0.2 g of titanium dioxide (anatase) base material was added, and after sufficient stirring, this suspension was sealed in a Teflon (registered trademark) container, and at 48C, 48 ° C. Hydrothermal reaction was performed by heating for a period of time. After completion of the reaction, the substrate was thoroughly washed with a centrifuge. This is to remove the aluminum silicate that could not be bonded to the surface of the base material, and the titanium dioxide base material and the produced aluminum silicate were used by utilizing their specific gravity difference, This is for separation and purification by centrifugation. Then, this was dried at 40 ° C. and normal pressure in an electric dryer to obtain titanium dioxide composite particles coated with silicate.

In the silicate-coated titanium dioxide composite particles obtained in this manner, the base anatase peak was confirmed from the X-ray diffraction pattern, and at the same time, a broad peak characteristic of the amorphous silicate component was observed. Was also confirmed. This material had a BET specific surface area of 158 m 2 / g by nitrogen adsorption, an average pore diameter of 12.58 nm, and a micro / meso region pore volume of 0.13 cm 3 / g. Further, as a result of chemical composition analysis by fluorescent X-ray analysis, this material has a TiO 2 content of 35.8% by mass, and an aluminum silicate having a weight ratio of about 65% by mass is a titanium dioxide base material. It was suggested that it was coated.

(Production of photocatalytic composite particles 6)
Dissolve sodium orthosilicate in deionized water to prepare 65 ml of 100 mmol / l sodium orthosilicate aqueous solution, add 4 ml of 1 mol / l sodium hydroxide aqueous solution to this aqueous solution, and add sodium orthosilicate / sodium hydroxide mixed aqueous solution. Prepared. Separately, aluminum chloride was dissolved in deionized water to prepare 100 ml of a 100 mmol / l aluminum chloride aqueous solution. Next, the sodium orthosilicate / sodium hydroxide mixed aqueous solution was added to this aluminum chloride aqueous solution and stirred at room temperature for 1 hour to obtain a precursor suspension. The silicon / aluminum ratio at this time was 0.65. In order to remove sodium chloride formed as a by-product during the production of this precursor, it was thoroughly washed with deionized water using a centrifuge. The resulting precursor was dispersed in 200 ml deionized water.

  To this precursor suspension, 0.2 g of titanium dioxide (anatase) base material was added, and after sufficient stirring, this suspension was sealed in a Teflon (registered trademark) container, and at 48C, 48 ° C. Hydrothermal reaction was performed by heating for a period of time. After completion of the reaction, the substrate was thoroughly washed with a centrifuge. This is to remove the aluminum silicate that could not be bonded to the surface of the base material, and the titanium dioxide base material and the produced aluminum silicate were used by utilizing their specific gravity difference, This is for separation and purification by centrifugation. Then, this was dried at 40 ° C. and normal pressure in an electric dryer to obtain titanium dioxide composite particles coated with silicate.

In the silicate-coated titanium dioxide composite particles obtained in this manner, the base anatase peak was confirmed from the X-ray diffraction pattern, and at the same time, a broad peak characteristic of the amorphous silicate component was observed. Was also confirmed. This material had a BET specific surface area of 179 m 2 / g by nitrogen adsorption, an average pore diameter of 9.89 nm, and a micro / meso region pore volume of 0.16 cm 3 / g. Further, as a result of chemical composition analysis by fluorescent X-ray analysis, this material has a TiO 2 content of 36.6% by mass, and an aluminum silicate having a weight ratio of about 65% by mass is a titanium dioxide base material. It was suggested that it was coated.

(Production of photocatalyst composite particles 7)
Sodium orthosilicate was dissolved in deionized water to prepare 70 ml of a 100 mmol / l sodium orthosilicate aqueous solution, and 2 ml of a 1 mol / l sodium hydroxide aqueous solution was added to this aqueous solution. Separately, aluminum chloride was dissolved in deionized water to prepare 100 ml of a 100 mmol / l aluminum chloride aqueous solution, and a sodium orthosilicate / sodium hydroxide mixed aqueous solution was prepared. Next, the sodium orthosilicate / sodium hydroxide mixed aqueous solution was added to this aluminum chloride aqueous solution and stirred at room temperature for 1 hour to obtain a precursor suspension. The silicon / aluminum ratio at this time was 0.70. In order to remove sodium chloride formed as a by-product during the production of this precursor, it was thoroughly washed with deionized water using a centrifuge. The resulting precursor was dispersed in 200 ml deionized water.

  After 0.2 g of titanium dioxide (anatase) base material was put into this precursor suspension and sufficiently stirred, this suspension was sealed in a Teflon (registered trademark) container, and then at 100 ° C. for 48 hours. A hydrothermal reaction was performed by heating. After completion of the reaction, the substrate was thoroughly washed with a centrifuge. This is to remove the aluminum silicate that could not be bonded to the surface of the base material, and the titanium dioxide base material and the produced aluminum silicate were used by utilizing their specific gravity difference, This is for separation and purification by centrifugation. Then, this was dried at 40 ° C. and normal pressure in an electric dryer to obtain titanium dioxide composite particles coated with silicate.

The titanium dioxide composite particles coated with the silicate thus obtained have a substrate anatase peak confirmed from the X-ray diffraction pattern, and at the same time, a broad peak characteristic of the amorphous silicate component is also present. confirmed. This material had a BET specific surface area of 198 m 2 / g by nitrogen adsorption, an average pore diameter of 7.76 nm, and a micro / meso region pore volume of 0.14 cm 3 / g. Further, as a result of chemical composition analysis by fluorescent X-ray analysis, this material has a TiO 2 content of 43.2% by mass, and an aluminum silicate having a weight ratio of about 55% by mass is a titanium dioxide base material. It was suggested that it was coated.

(Production of photocatalytic composite particles 8)
Sodium orthosilicate was dissolved in deionized water to prepare 75 ml of a 100 mmol / l sodium orthosilicate aqueous solution. Separately, aluminum chloride was dissolved in deionized water to prepare 100 ml of a 100 mmol / l aluminum chloride aqueous solution. Next, the sodium orthosilicate aqueous solution was added to the aluminum chloride aqueous solution and stirred at room temperature for 1 hour to obtain a precursor suspension. The silicon / aluminum ratio at this time was 0.75. In order to remove sodium chloride formed as a by-product during the production of this precursor, it was thoroughly washed with deionized water using a centrifuge. The resulting precursor was dispersed in 200 ml deionized water.

  To this precursor suspension, 0.2 g of titanium dioxide (anatase) base material was added, and after sufficient stirring, this suspension was sealed in a Teflon (registered trademark) container, and at 48C, 48 ° C. Hydrothermal reaction was performed by heating for a period of time. After completion of the reaction, the substrate was thoroughly washed with a centrifuge. This is to remove the aluminum silicate that could not be bonded to the surface of the base material, and the titanium dioxide base material and the produced aluminum silicate were used by utilizing their specific gravity difference, This is for separation and purification by centrifugation. Then, this was dried at 40 ° C. and normal pressure in an electric dryer to obtain titanium dioxide composite particles coated with silicate.

The titanium dioxide composite particles coated with the silicate thus obtained have a substrate anatase peak confirmed from the X-ray diffraction pattern, and at the same time, a broad peak characteristic of the amorphous silicate component is also present. confirmed. This material had a BET specific surface area of 193 m 2 / g by nitrogen adsorption, an average pore diameter of 9.77 nm, and a micro / meso region pore volume of 0.23 cm 3 / g. Further, as a result of chemical composition analysis by fluorescent X-ray analysis, this material has a TiO 2 content of 46.6% by mass, and an aluminum silicate having a weight ratio of about 55% by mass is a titanium dioxide base material. It was suggested that it was coated.

(Production of photocatalyst composite particles 9)
Sodium orthosilicate was dissolved in deionized water to prepare 80 ml of 100 mmol / l sodium orthosilicate aqueous solution. Separately, aluminum chloride was dissolved in deionized water to prepare 100 ml of a 100 mmol / l aluminum chloride aqueous solution, and 2 ml of 1 mol / l hydrochloric acid was added to this aqueous solution to prepare an aluminum chloride / hydrochloric acid mixed aqueous solution. Next, a sodium orthosilicate aqueous solution was added to the aluminum chloride / hydrochloric acid mixed aqueous solution and stirred at room temperature for 1 hour to obtain a precursor suspension. The silicon / aluminum ratio at this time was 0.80. In order to remove sodium chloride formed as a by-product during the production of this precursor, it was thoroughly washed with deionized water using a centrifuge. The resulting precursor was dispersed in 200 ml deionized water.

  To this precursor suspension, 0.2 g of titanium dioxide (anatase) base material was added, and after sufficient stirring, this suspension was sealed in a Teflon (registered trademark) container, and at 48C, 48 ° C. Hydrothermal reaction was performed by heating for a period of time. After completion of the reaction, the substrate was thoroughly washed with a centrifuge. This is to remove the aluminum silicate that could not be bonded to the surface of the base material, and the titanium dioxide base material and the produced aluminum silicate were used by utilizing their specific gravity difference, This is for separation and purification by centrifugation. Then, this was dried at 40 ° C. and normal pressure in an electric dryer to obtain titanium dioxide composite particles coated with silicate.

The titanium dioxide composite particles coated with the silicate thus obtained have a substrate anatase peak confirmed from the X-ray diffraction pattern, and at the same time, a broad peak characteristic of the amorphous silicate component is also present. confirmed. This material had a BET specific surface area of 200 m 2 / g by nitrogen adsorption, an average pore diameter of 9.51 nm, and a micro / meso region pore volume of 0.29 cm 3 / g. Further, as a result of chemical composition analysis by fluorescent X-ray analysis, this material has a TiO 2 content of 34.7% by mass, and an aluminum silicate of about 65% by mass is a titanium dioxide base material. It was suggested that it was coated.

(Manufacture of photocatalyst composite particle 10)
Sodium orthosilicate was dissolved in deionized water to prepare 85 ml of 100 mmol / l sodium orthosilicate aqueous solution. Separately, aluminum chloride was dissolved in deionized water to prepare 100 ml of a 100 mmol / l aluminum chloride aqueous solution, and 4 ml of 1 mol / l hydrochloric acid was added to this aqueous solution to prepare an aluminum chloride / hydrochloric acid mixed aqueous solution. Next, a sodium orthosilicate aqueous solution was added to the aluminum chloride / hydrochloric acid mixed aqueous solution and stirred at room temperature for 1 hour to obtain a precursor suspension. The silicon / aluminum ratio at this time was 0.85. In order to remove sodium chloride formed as a by-product during the production of this precursor, it was thoroughly washed with deionized water using a centrifuge. The resulting precursor was dispersed in 200 ml deionized water.

  To this precursor suspension, 0.2 g of titanium dioxide (anatase) base material was added, and after sufficient stirring, this suspension was sealed in a Teflon (registered trademark) container, and at 48C, 48 ° C. Hydrothermal reaction was performed by heating for a period of time. After completion of the reaction, the substrate was thoroughly washed with a centrifuge. This is to remove the aluminum silicate that could not be bonded to the surface of the base material, and the titanium dioxide base material and the produced aluminum silicate were used by utilizing their specific gravity difference, This is for separation and purification by centrifugation. Then, this was dried at 40 ° C. and normal pressure in an electric dryer to obtain titanium dioxide composite particles coated with silicate.

The titanium dioxide composite particles coated with the silicate thus obtained have a substrate anatase peak confirmed from the X-ray diffraction pattern, and at the same time, a broad peak characteristic of the amorphous silicate component is also present. confirmed. This material had a BET specific surface area of 201 m 2 / g by nitrogen adsorption, an average pore diameter of 9.66 nm, and a micro / meso region pore volume of 0.24 cm 3 / g. Further, as a result of chemical composition analysis by fluorescent X-ray analysis, this material has a TiO 2 content of 34.6% by mass, and an aluminum silicate having a weight ratio of about 65% by mass is a titanium dioxide base material. It was suggested that it was coated.

(Production of photocatalyst composite particles 11)
Sodium orthosilicate was dissolved in deionized water to prepare 90 ml of a 100 mmol / l sodium orthosilicate aqueous solution. Separately, aluminum chloride was dissolved in deionized water to prepare 100 ml of a 100 mmol / l aluminum chloride aqueous solution, and 6 ml of 1 mol / l hydrochloric acid was added to the aqueous solution to prepare an aluminum chloride / hydrochloric acid mixed aqueous solution. Next, a sodium orthosilicate aqueous solution was added to the aluminum chloride / hydrochloric acid mixed aqueous solution and stirred at room temperature for 1 hour to obtain a precursor suspension. The silicon / aluminum ratio at this time was 0.90. In order to remove sodium chloride formed as a by-product during the production of this precursor, it was thoroughly washed with deionized water using a centrifuge. The resulting precursor was dispersed in 200 ml deionized water.

  To this precursor suspension, 0.2 g of titanium dioxide (anatase) base material was added, and after sufficient stirring, this suspension was sealed in a Teflon (registered trademark) container, and at 48C, 48 ° C. Hydrothermal reaction was performed by heating for a period of time. After completion of the reaction, the substrate was thoroughly washed with a centrifuge. This is to remove the aluminum silicate that could not be bonded to the surface of the base material, and the titanium dioxide base material and the produced aluminum silicate were used by utilizing their specific gravity difference, This is for separation and purification by centrifugation. Then, this was dried at 40 ° C. and normal pressure in an electric dryer to obtain titanium dioxide composite particles coated with silicate.

The titanium dioxide composite particles coated with the silicate thus obtained have a substrate anatase peak confirmed from the X-ray diffraction pattern, and at the same time, a broad peak characteristic of the amorphous silicate component is also present. confirmed. This material had a BET specific surface area of 209 m 2 / g by nitrogen adsorption, an average pore diameter of 10.1 nm, and a micro / meso region pore volume of 0.34 cm 3 / g. Further, as a result of chemical composition analysis by fluorescent X-ray analysis, this material has a TiO 2 content of 34.7% by mass, and an aluminum silicate of about 65% by mass is a titanium dioxide base material. It was suggested that it was coated.

(Production of photocatalyst composite particles 12)
Sodium orthosilicate was dissolved in deionized water to prepare 95 ml of 100 mmol / l sodium orthosilicate aqueous solution. Separately, aluminum chloride was dissolved in deionized water to prepare 100 ml of a 100 mmol / l aluminum chloride aqueous solution, and 8 ml of 1 mol / l hydrochloric acid was added to this aqueous solution to prepare an aluminum chloride / hydrochloric acid mixed aqueous solution. Next, a sodium orthosilicate aqueous solution was added to the aluminum chloride / hydrochloric acid mixed aqueous solution and stirred at room temperature for 1 hour to obtain a precursor suspension. The silicon / aluminum ratio at this time was 0.95. In order to remove sodium chloride formed as a by-product during the production of this precursor, it was thoroughly washed with deionized water using a centrifuge. The resulting precursor was dispersed in 200 ml deionized water.

  To this precursor suspension, 0.2 g of titanium dioxide (anatase) base material was added, and after sufficient stirring, this suspension was sealed in a Teflon (registered trademark) container, and at 48C, 48 ° C. Hydrothermal reaction was performed by heating for a period of time. After completion of the reaction, the substrate was thoroughly washed with a centrifuge. This is to remove the aluminum silicate that could not be bonded to the surface of the base material, and the titanium dioxide base material and the produced aluminum silicate were used by utilizing their specific gravity difference, This is for separation and purification by centrifugation. Then, this was dried at 40 ° C. and normal pressure in an electric dryer to obtain titanium dioxide composite particles coated with silicate.

The titanium dioxide composite particles coated with the silicate thus obtained have a substrate anatase peak confirmed from the X-ray diffraction pattern, and at the same time, a broad peak characteristic of the amorphous silicate component is also present. confirmed. This material had a BET specific surface area of 138 m 2 / g by nitrogen adsorption, an average pore diameter of 13.0 nm, and a micro / meso region pore volume of 0.47 cm 3 / g. Further, as a result of chemical composition analysis by fluorescent X-ray analysis, this material has a TiO 2 content of 46.8% by mass, and an aluminum silicate having a weight ratio of about 65% by mass is a titanium dioxide base material. It was suggested that it was coated.

(Production of photocatalyst composite particles 13)
Sodium orthosilicate was dissolved in deionized water to prepare 100 ml of 100 mmol / l sodium orthosilicate aqueous solution. Separately, aluminum chloride was dissolved in deionized water to prepare 100 ml of a 100 mmol / l aluminum chloride aqueous solution, and 10 ml of 1 mol / l hydrochloric acid was added to this aqueous solution to prepare an aluminum chloride / hydrochloric acid mixed aqueous solution. Next, a sodium orthosilicate aqueous solution was added to the aluminum chloride / hydrochloric acid mixed aqueous solution and stirred at room temperature for 1 hour to obtain a precursor suspension. The silicon / aluminum ratio at this time was 1.00. In order to remove sodium chloride formed as a by-product during the production of this precursor, it was thoroughly washed with deionized water using a centrifuge. The resulting precursor was dispersed in 200 ml deionized water.

  To this precursor suspension, 0.2 g of titanium dioxide (anatase) base material was added, and after sufficient stirring, this suspension was sealed in a Teflon (registered trademark) container, and at 48C, 48 ° C. Hydrothermal reaction was performed by heating for a period of time. After completion of the reaction, the substrate was thoroughly washed with a centrifuge. This is to remove aluminum silicate that could not be bonded to the substrate surface, and to separate and purify the titanium dioxide substrate and the produced aluminum silicate by centrifugation. . Then, this was dried at 40 ° C. and normal pressure in an electric dryer to obtain titanium dioxide composite particles coated with silicate.

In the silicate-coated titanium dioxide composite particles obtained in this manner, the base anatase peak was confirmed from the X-ray diffraction pattern, and at the same time, a broad peak characteristic of the amorphous silicate component was observed. Was also confirmed. This material had a BET specific surface area of 184 m 2 / g by nitrogen adsorption, an average pore diameter of 11.5 nm, and a micro / meso region pore volume of 0.26 cm 3 / g. Further, as a result of chemical composition analysis by fluorescent X-ray analysis, this material has a TiO 2 content of 41.3% by mass, and an aluminum silicate having a weight ratio of about 60% by mass is a titanium dioxide base material. It was suggested that it was coated. Table 1 shows the results of physical property evaluation of titanium dioxide composite particles coated with silicate.

As is apparent from Table 1, this material has a BET specific surface area of about 200 m 2 / g by nitrogen adsorption, an average pore diameter of about 8 to 13 nm, and a micro / meso region pore volume of 0.1. To about 0.4 cm 3 / g, a TiO 2 content of about 35 to 45% by mass, and a silicate in which an aluminum silicate of about 60% by mass is coated with a titanium dioxide substrate. It was confirmed that the titanium dioxide composite particles coated with (1) were synthesized.

(1) Production preparation of emulsion paint The em