JP2004231952A - Composite particle and its preparation process and use - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composite particle which can effectively derive functions possessed by titanium oxide and has little restriction in practicality. <P>SOLUTION: The composite particle is composed of smaller particles and larger particles, wherein the smaller particles are supported on the larger particles, and the smaller particles are titanium oxide-silica composite fine particles having 0.02-0.5 μm of average particle size calculated from the BET specific surface area, and the larger particles have 2-200 μm of average particle size measured by laser diffraction/scattering type particle size analysis. The composite particle is prepared by mixing a raw material including the larger particles and the smaller particles at a specified energy constant k. Organic polymer compositions, coating agents, paints, structures, cosmetics, fibers and films may be manufactured by using the composite particle. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a composite particle, a method for producing the composite particle, and a use thereof, and relates to a technique for effectively exhibiting its function by compounding titanium oxide having photocatalytic ability.

  The photocatalytic ability of titanium oxide will be described. Titanium oxide absorbs ultraviolet light and generates electrons and holes therein. The holes react with the water adsorbed by the titanium oxide to generate hydroxy radicals, and decompose organic substances adsorbed on the surface of the titanium oxide particles into carbon dioxide gas and water (Non-Patent Document 1). This is called a photocatalytic action. Conditions of the titanium oxide having such a strong action include that holes are easily generated and holes easily reach the titanium oxide surface. "All of titanium oxide photocatalysts" (Non-Patent Document 2) mentions titanium oxide having high photocatalytic activity, such as anatase-type titanium oxide, titanium oxide having few lattice defects, and titanium oxide having small particles and large specific surface area. .

  Since this photocatalytic action can decompose most organic substances, by supporting titanium oxide on the surface of tiles, building materials, building structural materials, fibers, films, etc., antibacterial, self-cleaning, deodorizing, antifouling, etc. Functions can be provided.

However, since the photocatalysis occurs on the surface of titanium oxide, it is necessary to arrange titanium oxide on the surface of the member. Usually, as a simple method, a method in which titanium oxide is mixed with a binder and applied to a member is performed. However, when an organic polymer is used as a binder, the binder is oxidized and decomposed by a photocatalytic action. Therefore, it is necessary to use a hardly decomposable binder such as a fluororesin or a silicone resin (Patent Document 1). , 2).
However, when photocatalyst semiconductor particles are used in combination with these resin binders, the binder coats the surface of the titanium oxide, hinders the light and decomposed substances from reaching the photocatalyst particles, and reduces the effect of the photocatalytic action. was there. In addition, it was necessary to cure the resin by heating.
Next, the composite particles will be described. Titanium oxide particles have been combined for various purposes. In many cases, the composite is formed by a combination of large-diameter particles (hereinafter, referred to as base particles) and small-diameter particles (hereinafter, referred to as child particles). The base particles are used to more effectively bring out the functions of the child particles. Used for If there is no significant difference in particle size, fine particles having the expected function will be referred to as child particles, and particles used for effectively expressing them will be referred to as mother particles.

  When complexed with titanium oxide, titanium oxide is mostly used as a child particle. This is because titanium oxide has a wide variety of functions such as concealing ability, photocatalytic ability, and ultraviolet shielding ability, and mother particles are selected in order to effectively exhibit those functions. For example, in order to maximize the ultraviolet shielding ability of the titanium oxide ultrafine particles, a method using base particles defined by a difference in refractive index and a band gap (Patent Documents 3 to 5), imparting transparency for the same purpose. For this purpose, there is a method in which silica particles are used as base particles (Patent Document 6), and a method in which titanium oxide is combined with calcium carbonate particles as base particles in order to suitably express the concealing property of titanium oxide (Patent Document 7). Further, in order to effectively exhibit the photocatalytic ability of titanium oxide, a method of supporting titanium oxide with an organic binder on the surface of an inorganic powder (Patent Document 8), without deteriorating the resin even when the resin contacts the resin. There is a method of using aluminosilicate particles as base particles to exhibit photocatalytic ability (Patent Document 9). In addition, as a method of compounding particles, there are a high-speed airflow impact method in which base particles and child particles are mechanically bonded (Patent Documents 10 to 11), a surface fusion method (Patent Document 12), and the like.

Patent No. 2756474 Japanese Patent No. 3027739 JP-A-11-131048 JP-A-9-100112 JP-A-8-268707 JP 2000-344509 A JP 2002-29739 A Patent No. 3279755 JP-A-11-76835 Japanese Patent Publication No. 3-2009 JP-A-6-210152 Patent No. 2672671 "Light Clean Revolution", Akira Fujishima, Kazuhito Hashimoto, Toshiya Watanabe, CMC Corporation, (1997) "All about titanium oxide photocatalyst" Kazuhito Hashimoto, Akira Fujishima Editing, CMC Corporation, (1998)

  Since titanium oxide has a photocatalytic ability, it has very many restrictions in practical use. That is, when an organic polymer is used as the binder, the binder is oxidized and decomposed by the photocatalytic action. Even if a hardly decomposable binder such as a fluororesin or silicone resin is used, the surface of the titanium oxide is covered, preventing light and the substance to be decomposed from reaching the photocatalyst particles, and reducing the effect of the photocatalysis. I will. In addition, it was necessary to cure the resin by heating. In addition, such a problem was unavoidable even in the case of composite particles in order to sufficiently exhibit the function of titanium oxide. It is an object of the present invention to propose particles that effectively extract the function of titanium oxide and have few practical restrictions.

  As a result of intensive studies by the present inventors, it has been found that the above problem can be solved by using titanium oxide-silica composite fine particles as child particles and forming large particles and composite particles. Reached. That is, the present invention includes the following embodiments.

(1) The small particles are titanium oxide-silica composite fine particles having an average particle size of 0.02 μm to 0.5 μm in terms of BET specific surface area, and these small particles are measured by a laser diffraction / scattering particle size analysis method. Composite particles characterized by being supported by large particles having an average particle size of 2 to 200 µm.
(16) The composite particles according to (1), wherein the large particles are spherical resin particles having a melting point of 150 ° C. or higher.
(3) The composite particles according to (1), wherein the large particles are hydroxides, oxides, or carbonates containing at least one selected from the group consisting of Al, Mg, Ca, and Si.
(17) The composite particles according to any one of (1) to (3), wherein the ratio of silica in the small particles is 0.5% by mass or more and less than 50% by mass.
(18) The composite particles according to any one of (1) to (4), wherein the ratio of the small particles to the large particles is 0.5% by mass or more and less than 40% by mass.
(19) A material containing large particles and small particles is dry-mixed by a ball mill, and the energy constant k of the dry mixing is such that the total mass of the particles to be mixed is wp (g), the mass of the media is wm (g), and the inner diameter of the ball mill container is Is d (m), the number of rotations is n (rpm), and the mixing time is t (minutes).
k = (wm / wp) × d × n × t (1) The composite particle according to any one of (1) to (5), wherein k represented by the relationship represented by the expression is 50 or more and 50,000 or less. Manufacturing method.
(7) In a powder processing apparatus of a type in which a material containing large particles and small particles is mixed, pulverized, and stirred by the rotation of the blade, the rotation speed of the blade is n (rpm), and the mixing time is t (minute). Sometimes
k2 = n × t The method for producing composite particles according to any one of (1) to (5), wherein k2 represented by the relationship represented by the expression (2) is 250 or more and 50,000 or less.
(8) In a powder processing apparatus of a type in which materials containing large particles and small particles are mixed, crushed and stirred by shaking, when the number of shaking (times / minute) is n and the mixing time is t (minutes),
k3 = n × t
The method for producing composite particles according to any one of (1) to (5), wherein k3 represented by the following relationship is 50 or more and 50,000 or less.
(9) An organic polymer composition comprising the composite particles according to any one of (1) to (5) in an amount of 0.01 to 80% by mass based on the total mass of the composition.
(10) The organic polymer according to (9), wherein the organic polymer of the organic polymer composition is at least one resin selected from the group consisting of a synthetic thermoplastic resin, a synthetic thermosetting resin, and a natural resin. Coalescing composition.
(11) The organic polymer composition according to (9) or (10), wherein the organic polymer composition is a compound.
(12) The organic polymer composition according to (9) or (10), wherein the organic polymer composition is a master batch.
(13) A molded article obtained by molding the organic polymer composition according to any one of (9) to (12).
(14) A coating agent comprising the composite particles according to any one of (1) to (5).
(15) A paint containing the composite particles according to any one of (1) to (5).
(16) A structure having on its surface the composite particles according to any one of (1) to (5).
(17) A cosmetic comprising the composite particles according to any one of (1) to (5).
(18) A fiber containing the composite particle according to any one of (1) to (5).
(19) A film containing the composite particles according to any one of (1) to (5).

When the composite particles of the present invention are kneaded with a resin to form a film or fiber, or when a film is formed on the surface of a structure together with a resin binder, particles having photocatalytic ability are exposed from the resin, so-called `` heads ''. Are particles that can be effectively performed. Therefore, the resin used as the composite particle carrier is hardly decomposed while sufficiently exhibiting the photocatalytic ability. As a result, a structure, a film, or the like having excellent weather resistance can be obtained. In addition, it is possible to simultaneously solve the inexpensive loading of the photocatalyst particles and the durability.

  The present invention is characterized in that it is a composite particle using titanium oxide-silica composite fine particles as child particles.

  The reason why the titanium oxide-silica composite fine particles are effective as the child particles is that the titanium oxide component in the particles has a photocatalytic function and the silica component in the particles is strong enough to connect the mother particle and the child particles. It is for expressing the function as a good binder. In particular, it is more preferable to use a substance that strongly binds to the silica component as the base particle. By using the titanium oxide-silica composite fine particles as the child particles as described above, it is possible to produce a structure that exhibits a photocatalytic ability and has excellent durability even when a normal organic polymer binder is used. Was.

  Furthermore, in the present invention, since the titanium oxide-silica composite fine particles as the child particles are compounded with the base particles having an appropriate size, the composite particles of the present invention are mixed into a resin or the like to form a film or a fiber. In the case, when applied to a substrate surface together with a binder, or when introduced into a structural member, a part of the base particles can be exposed on the surface of the film, fiber, coating film or structure. Thus, the titanium oxide component on the surface of the base particles can be exposed. Furthermore, even when an organic polymer is used as the binder, since the surface of the base particles having no photocatalytic ability is in contact with and bonded to the binder, a portion of the organic binder in contact with the titanium oxide is oxidized by the photocatalytic action of the titanium oxide. Even if decomposed, the binding between the organic binder and the composite particles is maintained, so that the titanium oxide-silica composite fine particles on the surface of the base particles do not fall off from the base particles. Therefore, by using the composite particles of the present invention, a structure that can exhibit photocatalytic activity for a long period of time can be obtained. Therefore, it is not necessary to use a hardly decomposable binder such as an expensive fluororesin or silicone resin.

Hereinafter, details of the invention will be described.
The specific titanium oxide-silica composite fine particles referred to in the present invention are preferably composite metal oxides (mixed crystal particles) in which titanium oxide and silicon oxide are primary particles and exhibit a mixed crystal state. The method for producing the ultrafine mixed crystal oxide in which titanium oxide and silicon oxide are in a mixed crystal state in primary particles may be a liquid phase method or a gas phase method, and is not particularly limited. It can be produced by a method as disclosed in WO 01/56930. For example, a mixed gas and an oxidizing gas containing at least one compound selected from titanium chloride, bromide and iodide, and at least one compound selected from silicon chloride, bromide and iodide at 500 ° C. It is manufactured by performing a gas phase reaction after preheating as described above.

The ultrafine composite particles used in the present invention may have a core (nucleus) / shell (shell) structure by a different metal oxide crystal structure when a function other than the photocatalytic ability of titanium oxide is expected. In the titanium oxide-silica composite fine particles including a mixed crystal state in which a titanium-oxygen-silicon bond is present in the primary particles, a structure in which the core is rich in the TiO ₂ phase and the shell is rich in the SiO ₂ phase is also possible. The form in which the silicon oxide phase is present in the shell may be a dense layer, or may be in the form of an island, an island, or a muskmelon.

  However, regardless of the use, it is preferable that the child particles of the present invention are not a simple mixture of titanium oxide powder and silica powder. In addition, any of anatase type, rutile type and brookite type can be preferably used as titanium oxide contained in the composite metal oxide in which titanium oxide and silicon oxide are primary particles and show a mixed crystal state. From the viewpoint of high photocatalytic activity, it is preferable to include anatase-type or brookite-type titanium oxide. From the viewpoint of UV shielding, a rutile type or an anatase type is preferable.

The primary particles of the present invention preferably have a primary particle diameter (in the present invention, a particle diameter calculated from the BET specific surface area) of 0.02 to 0.5 μm (20 to 500 nm), and more preferably 0.1 to 0.5 μm (20 to 500 nm). It is from 0.05 to 0.2 μm, preferably from 0.07 to 0.15 μm. Since the photocatalytic activity of the photocatalyst increases as the particle diameter decreases, that is, as the specific surface area increases, the primary particle diameter is preferably 0.5 μm or less. If the primary particle diameter of the child particles is smaller than 20 nm, the powder containing the child particles may be bulky and difficult to handle, or the productivity may be extremely deteriorated. Even when the primary particle diameter of the secondary particles is larger than 500 nm, the photocatalytic function may be undesirably reduced.
The average particle size calculated from the BET specific surface area can be obtained by converting the particles into a sphere and using the following formula.
D1 = 6 / ρS (where ρ is the specific gravity of the particle, and S is the specific surface area of the particle)

  The silica concentration in the child particles is 0.5 to 50% by mass, preferably 1 to 30% by mass, more preferably 1.5 to 25% by mass. When the composition of silicon oxide is lower than 0.5% by mass, yellowing and reduction in strength of the organic structure containing the same due to light irradiation are observed. This is probably because the contact probability between titanium oxide and the organic component is increased. If the silicon oxide particles are more than 50% by mass, there is a disadvantage that the function of the titanium oxide photocatalyst is hardly exhibited. This is because the proportion of the titanium oxide in the child particles is small.

  As the base particles, particles having an average particle size of 2 to 200 μm, desirably 3 to 100 μm, more preferably 3 to 80 μm as measured by a laser diffraction / scattering particle size analysis method are used. When the particle size is in this range, it is suitable for disposition on the surface of the member. When the particle size is smaller than this range, it is difficult to dispose the particle on the surface of the member. In the present invention, the dimensions of the mother particles (large particles) and the child particles (small particles) of the composite particles are the dimensions after the compounding. Therefore, when the large particles and the small particles are mixed and pulverized to form a composite, the size of the large particles before the treatment may be larger than the average particle diameter of 200 μm measured by the laser diffraction / scattering particle size analysis method. Conversely, if the dimension before processing is 2 μm or more and less than 2 μm after processing, it is outside the scope of the present invention. The same applies to small particles, but generally, the small particles are not substantially refined by the complexing treatment.

  For the base particles, use spherical resin particles having a melting point of 150 ° C. or more and an average particle size measured by a laser diffraction / scattering particle size analysis method of 2 to 200 μm, desirably 3 to 100 μm, and more preferably 3 to 80 μm. Is also possible. Spherical particles are used when performing compounding treatment (ball milling, etc.) when overfilling the compounds to be treated, that is, sticking between the objects to be treated or between the objects to be treated and the processing medium (such as balls). It is not to cause. The reason why the melting point is 150 ° C. or higher is that the composite particles are heated when kneaded and molded with another resin, so that the shape of the mother particles is maintained and the function of the child particles is exhibited.

  In addition, a hydroxide, an oxide, or a carbonate containing at least one selected from the group consisting of Al, Mg, Ca, and Si can be used for the base particles. For example, it is preferable to use hydroxide particles or oxide particles of Al, Mg, or Ca, or carbonate particles of Ca, or silica particles. Aluminum hydroxide, magnesium hydroxide, calcium hydroxide, aluminum oxide, magnesium oxide And particles such as calcium oxide, calcium carbonate, and silica. Further, the base particles may be a composite thereof. The average particle size measured by a laser diffraction / scattering particle size analysis method is 2 to 200 μm, desirably 3 to 100 μm, and more preferably 3 to 80 μm, regardless of the shape. Particles obtained by any method may be used.

  Base particles composed of these substances are mixed, crushed, and agitated by rotating blades when a process in which the energy constant k in dry mixing by a rolling method such as a ball mill is 50 to 50,000 is performed. When the energy constant k2 is 250 or more and 50,000 or less in the powder processing apparatus, the energy constant k3 is 50 or more and 50,000 or less in the type of powder processing apparatus that performs mixing, crushing, and stirring by shaking. In this case, it is possible to strongly bond with the silica component in the child particles.

  The composite of the child particles (small particles) and the base particles (large particles) can be performed by subjecting the small particles and the large particles or the preliminary particles of the large particles to a mixing operation with a predetermined energy constant. During the mixing operation, the powder is activated by energies such as impact, friction, and shear given to the powder by the pulverizing, mixing, and stirring media to activate the powder to form a composite.

The ball mill is the most general-purpose mixing and pulverizing apparatus, but it is also suitable as a compounding apparatus by selecting conditions, since the energy received by the compound can be quantified. The energy consumed for this compounding can be represented by an energy constant k as an index. The energy constant k has been proposed as an index for unifying and evaluating the mixing and crushing effects of a rolling ball mill (LD Hart and LK Hadson, The American Ceramic Society Bulletin, 43, No. 1, ( 1964)), and is represented by the following equation.
k = (wm / wp) × d × n × t Equation (1) (where k is an energy constant, wp is the total mass (g) of the powder to be mixed, wm is the media mass (g), and d is a ball mill container. Inner diameter (m), n indicates rotation speed (rpm), and t indicates mixing time (minute).)
Further, in a powder processing apparatus of a type in which mixing, pulverization, and stirring are performed by rotation of a blade, when the rotation speed of the blade is n (rpm) and the processing time is t (minute),
k2 = n × t Let k2 represented by the relationship of the equation (2) be an energy constant.
In a powder processing apparatus of the type that mixes, grinds, and agitates by shaking, when the number of shakings (times / minute) is n and the mixing time is t (minutes),
k3 = n × t Let k3 represented by the relationship of the equation (3) be an energy constant.

  The higher the energy constants are, the more the collision, friction and shear energy received by the powder increases, and the more easily the particles are bonded to the parent particles.

In the method for producing composite particles according to the present invention, in an apparatus for applying energy to a powder by rolling a pulverizing / mixing medium such as a ball mill, the energy constant k of the mixing operation of large particles and child particles is 50 to 50. 2,000 or less. Preferably it is 750 or more and 20,000 or less, more preferably 1,000 or more and 15,000 or less.
In a device for applying energy to the powder by the rotation of the blade, the energy constant k2 is preferably 250 or more and 50,000 or less. Preferably it is 500 or more and 20,000 or less, more preferably 700 or more and 15,000 or less.
In an apparatus for applying energy to the powder by shaking of the pulverizing / mixing medium, the energy constant k3 is preferably from 50 to 50,000, preferably from 250 to 20,000, more preferably from 700 to 15,000. Is good. When the energy constant is lower than the above lower limit, the activity of the surface of the powder becomes insufficient, and the bonding between particles hardly occurs. If the energy constant is higher than the upper limit, the pulverization proceeds excessively, and not only the particles become fine, but also the active surface relatively increases, which may cause inconveniences such as compaction and coarse particles being generated. Many. Further, it is not preferable because it is bonded to a pulverizing medium, a container, and the like, and causes adhesion of the compound and the medium to the medium and adhesion to the container.
In addition to general-purpose ball mills, the rotary blade type can be exemplified by Kawata's Super Mixer Co., Ltd. for the rotary blade type, and the paint shaker by Asada Tekko Co., Ltd. for the seismic type. And a mesofusion (registered trademark) of Hosokawa Micron Co., Ltd., a fluidized-flow dryer, a gas-flow impact method, a surface fusion method, and the like, but are not particularly limited to these apparatuses.

It is important to appropriately adjust the energy required for compounding also in compounding methods other than those exemplified above. In cases other than the rolling type, the rotary blade type, and the seismic type, the power applied to the processed material per unit mass may be set to be the same as the power range defined from the energy constant of the ball mill.
Various mixing and pulverization methods such as a rolling ball mill, a high-speed rotary pulverizer, a medium stirring type mill, a high-speed air impact method, and a surface fusing method, and a mechanical fusing device can be used as a mixing method capable of compounding particles. . The operating factors include, for example, in the case of a high-speed rotary pulverizer, adjustment of the rotation speed, residence time, and the like, and in the case of a medium stirring type mill, adjustment of the stirring speed, media mass, stirring time, and the like. In the high-speed air impact method pulverizer, the pressure of the carrier gas, the residence time, and the like are adjusted to give appropriate energy to the object to be processed.

  In the compounding process, generally, the ratio of the child particles to the base particles is measured so as to be 0.5% by mass or more and less than 40% by mass, and is then charged into the compounding device.

  The composite particles of the present invention can be used in almost the same applications as conventional titanium oxide, such as resin products, rubber products, paper, cosmetics, paints, printing inks, ceramic products, dye-sensitized solar cells, photocatalysts, and the like. Can be.

  The composite particles of the present invention can be used as a composition by, for example, adding to an organic polymer. Examples of the organic polymer include a synthetic thermoplastic resin, a synthetic thermosetting resin, and a natural resin. Specific examples of such an organic polymer include, for example, polyolefins such as polyethylene, polypropylene, and polystyrene; polyamides such as nylon 6, nylon 66, and aramid; polyesters such as polyethylene terephthalate and unsaturated polyester; polyvinyl chloride; Vinylidene, polyethylene oxide, polyethylene glycol, silicone resin, polyvinyl alcohol, vinyl acetal resin, polyacetate, ABS resin, epoxy resin, vinyl acetate resin, cellulose and rayon and other cellulose derivatives, polyurethane, polycarbonate, urea resin, fluororesin, polyfluoroethylene Examples include vinylidene chloride, phenolic resin, celluloid, chitin, starch sheet, acrylic resin, melamine resin, and alkyd resin.

  These organic polymer compositions containing the composite particle particles of the present invention are used, for example, for paints (coating compositions), compounds (for example, powder-containing resin compositions), and molded articles containing the composite particle particles at a high concentration. It can be used in the form of a master batch or the like. Additives such as an antioxidant, an antistatic agent, and a metal fatty acid salt may be added to the organic polymer composition.

  The concentration of the composite particles of the present invention in the organic polymer composition is preferably from 0.01 to 80% by mass, particularly preferably from 0.01 to 60% by mass, and still more preferably from 1 to 60% by mass, based on the total mass of the composition. It is 50% by mass, but most preferably 1 to 40% by mass.

By molding such a polymer composition, a molded article having ultraviolet shielding ability can be obtained. Examples of such a molded body include a fiber, a film, and a plastic molded body.
The fibers include polyolefin fibers, polyamide fibers, polyester fibers, acrylic fibers, rayon fibers and the like. In addition, these fibers can be used to produce various photocatalytic fiber products. Cloth products such as towels, towels, towels, eyeglass wipes, handkerchiefs, nursing cloth products such as pajamas, diapers, sheets, toilet seat covers, blankets, futons, bedding, underwear such as underwear and socks, masks, white coats, nurses Hospital textile products such as caps, curtains and sheets, sports textile products such as supporters, trainers and jerseys, automobile seats, seat covers, automotive ceiling materials, automotive flooring and other automotive textile products, carpets, curtains and foot wipes Household textile products such as mats, goodwill, chair and sofa fabrics, and clothing textile products such as sweaters. It can also be used for paper products such as wallpaper and shoji using the photocatalytic fibers.
Films include garbage bags, food packaging bags, wrap films, shrink films for PET bottles, and decorative films such as decorative boards. Molded products include resin parts for wash basin units, bath units, sink units, and handrails. Resin parts, TVs, personal computers, air conditioner indoor units, copy machines, washing machines, dehumidifiers, resin bodies for telephones, electric pots, vacuum cleaners, etc., resin covers for lighting fixtures, resin hangers, resin clothes cases, resin garbage And car dashboards.

  The composite particle particles of the present invention are generally blended into an organic polymer composition and molded to obtain the effect that large particles of the composite particles are caught, but the organic polymer composition is molded into fibers or films. In this case, the fiber diameter or the film thickness is not particularly limited, but is preferably 2 times or more and 200 times or less, more preferably 5 times or more and 100 times or less of the base particle diameter.

  Further, the composite particles of the present invention can be made into a coating agent by optionally adding a binder after being dispersed in water or an organic solvent. The binder material is not particularly limited, and may be an organic binder or an inorganic binder.

  As such a binder, for example, polyvinyl alcohol, melamine resin, urethane resin, celluloid, chitin, starch sheet, polyacrylamide, acrylamide, polyester such as unsaturated polyester, polyvinyl chloride, polyvinylidene chloride, polyethylene oxide, polyethylene glycol, Silicone resin, vinyl acetal resin, epoxy resin, vinyl acetate resin, polyurethane, urea resin, fluororesin, polyvinylidene fluoride, phenol resin and the like can be mentioned. Further, as an inorganic binder, for example, zirconium oxychloride, zirconium hydroxychloride, zirconium nitrate, zirconium sulfate, zirconium acetate, zirconium ammonium carbonate, zirconium compounds such as zirconium propionate, silicon compounds such as alkoxysilane, silicate, or aluminum or Titanium metal alkoxide and the like can be mentioned.

  Further, specifically, the addition amount of the binder in the coating agent is preferably from 0.01% by mass to 20% by mass, and particularly preferably from 1% by mass to 10% by mass.

  If the content of the binder is 0.01% by mass or less, sufficient adhesiveness cannot be obtained after coating, and if it exceeds 20% by mass, problems such as thickening occur, and it is economically disadvantageous.

  Further, the composite particles of the present invention may be provided on the surface of the structure. Such a structure is not particularly limited. For example, the structure may be made of an inorganic material such as metal, concrete, glass, and pottery, or may be made of an organic material such as paper, plastic, wood, and leather. Or a combination thereof. Examples of these include, for example, building materials, machinery, vehicles, glass products, home appliances, agricultural materials, electronic devices, tools, tableware, bath products, toilet products, furniture, clothing, cloth products, textiles, leather products, paper products, Examples include sports goods, gauntlets, containers, glasses, signs, plumbing, wiring, metal fittings, sanitary materials, automobile supplies, outdoor goods such as tents, stockings, socks, gloves, and masks.

  The method for providing these on the surface is not particularly limited. For example, the above-described organic polymer composition or coating agent may be directly applied to the structure, or may be already applied to the surface. It may be applied on a structure having a film. In the case of forming a film by applying a coating agent, an effect that the composite particles are caught by the film formation can be obtained. The thickness is not particularly limited, but is preferably 2 times or more and 200 times or less, more preferably 5 times or more and 100 times or less of the mother particle diameter. Further, another coating film may be formed on these. In this case, a film that does not cover the crested portion of the composite particles or that easily transmits a substance involved in a photocatalytic reaction is desirable.

  Further, the composite particles of the present invention can be used for cosmetics and the like. The cosmetic using the composite particles of the present invention is superior in smoothness when applied to the skin as compared with the cosmetic using only the child particles, that is, the titanium oxide-silica composite fine particles. This effect is particularly remarkable when the base particles are spherical nylon particles. Composite particles in which titanium oxide-silica composite fine particles are supported on spherical nylon particles are not only excellent in smoothness and feel when applied to the skin, but also have ultraviolet shielding ability. This cosmetic includes oils, whitening agents, moisturizers, anti-aging agents, emollients, extracts, anti-inflammatory agents, antioxidants, surfactants, chelating agents, antibacterial agents, and preservatives that are commonly used in cosmetics. Various additives such as agents, amino acids, saccharides, organic acids, alcohols, esters, oils and fats, hydrocarbons, UV inhibitors, inorganic powders and the like can be added.

  Specifically, solvents such as ethanol, isopropanol, butyl alcohol and benzyl alcohol, and polyhydric alcohols such as glycerin, propylene glycol, sorbitol, polyethylene glycol, dipropylene glycol, 1,3-butylene glycol, and 1,2-pentanediol , Saccharides such as sorbitol, disaccharides such as trehalose, hyaluronic acid, humectants such as water-soluble collagen, hydrogenated squalane and olive oil, vegetable oils such as jojoba oil, emollients such as ceramides, magnesium ascorbate, Stable ascorbic acid such as ascorbic acid glucoside, arbutin, kojic acid, ellagic acid, rucinol, whitening agent such as camillet extract, anti-inflammatory agent such as allantoin, glycyrrhizic acid or salts thereof, Nonionic surfactants such as glycerin stearate, POE sorbitan fatty acid ester, sorbitan fatty acid ester, POE alkyl ether, POE / POP block polymer, POE hydrogenated castor oil ester, and anionic surfactants such as fatty acid soap and sodium alkyl sulfate , Squalane, liquid paraffin, paraffin, isoparaffin, petrolatum, hydrocarbons such as α-olefin oligomers, almond oil, cacao oil, macadamia nut oil, avocado oil, castor oil, sunflower oil, evening primrose oil, safflower oil, rapeseed oil, horse Oils, fats such as oil, beef tallow, synthetic triglyceride, waxes such as beeswax, lanolin, jojoba oil, lauric acid, atearic acid, oleic acid, isostearic acid, myristyl acid, palmitic acid, beheni Acid, glycolic acid, fatty acids such as tartaric acid, higher alcohols such as cetanol, stearyl alcohol, behenyl alcohol, octyldodecyl alcohol, etc .; synthetic esters such as glycerin triester and pentaerythritol tetraester; dimethylpolysiloxane and methylphenylpolysiloxane. Chelating agents such as silicone oil, EDTA, gluconic acid, phytic acid, sodium polyphosphate, paraben, sorbic acid, isopropylmethylphenol, cresol, benzoic acid, benzoic acid, ethyl, stearyldimethylbenzylammonium chloride, hinokitiol, furfural, and sodium pyrithione Preservatives, bactericides, vitamin E, dibutylhydroxytoluene, sodium hydrogen sulfite, butylhydroxyanisole, etc. Antioxidants, buffering agents such as citric acid, sodium citrate, lactic acid, and sodium lactate; amino acids such as glycine and alanine; esters such as butyl myristate, ethyl oleate, and ethyl stearate; flavors, pigments, animals and plants Extracts, vitamins such as vitamins A, B, and C and derivatives thereof, para-aminobenzoic acid, octyl para-dimethylaminobenzoate, ethyl para-aminobenzoate, phenyl salicylate, benzyl cinnamate, octyl methoxycinnamate, sinoxate, urocanin UV absorbers such as ethyl acid, hydroxymethoxybenzophenone, dihydroxybenzophenone, mica, talc, kaolin, calcium carbonate, silicic acid, aluminum oxide, magnesium carbonate, barium sulfate, cerium oxide, red iron oxide, black oxide Beam can be used ultramarine, black iron oxide, inorganic powders such as yellow iron oxide, nylon powder, resin powder of polymethyl methacrylate powder, etc. and the like.

  The cosmetics referred to in the present invention can be manufactured by using a technique generally used in manufacturing, except for parts relating to the present invention.

Hereinafter, the present invention will be described specifically with reference to Examples, but the present invention is not limited to these Examples.
The following evaluation was performed in the following Examples and Comparative Examples.

(1) Photocatalytic Property of Film 20 parts by mass of the composite particles of the present invention, 2 parts by mass of zinc stearate (Zinc Stearate S, manufactured by NOF Corporation), and low-density polyethylene (manufactured by Nippon Polyolefin Co., Ltd., JELEX) JH607C) was melt-kneaded at 140 ° C (residence time: about 3 minutes) using a twin-screw kneading extruder (KZW15-30MG, manufactured by Technovel) to pelletize. A low-density polyethylene compound having a diameter of 2 to 3 mm, a length of 3 to 5 mm, a mass of 0.01 to 0.02 g, a columnar shape and a composite particle content of 20% is obtained.

4 kg of this low-density polyethylene compound and 16 kg of low-density polyethylene (manufactured by Nippon Polyolefin Co., Ltd., Jerex JH607C) were mixed for 10 minutes in a V-type blender (RKI-40, manufactured by Ikemoto Rika Kogyo Co., Ltd.) to produce mixed pellets. .
Next, an 80 μm film was produced from the obtained mixed pellets at a die temperature of 250 ° C. using a twin-screw kneading extruder (KZW15-30MG, manufactured by Technovel Corporation) having a 200 mm T-die.

The test ink was dripped on the thus obtained film so as to form a circle having a diameter of about 2 cm to obtain an ink decolorization test sample. The test ink used was a solution in which 1 g of a color printer ink (BJI201M-Magenta manufactured by Canon Inc.) was dissolved in 99 g of ethanol.
The ink erasure test sample was placed at a position 5 cm from the glass window, exposed to sunlight through the glass, and observed on the third day of clear weather, and the degree of erasure was visually determined.
(2) Hydrogen sulfide deodorization test A 5 L capacity Tedlar (registered trademark) bag (manufactured by GL Sciences Inc., AAK-5) so that the total area of the photocatalyst surface of the specimen irradiated with light becomes 400 cm ^2. Put in. Then, 5 L of dry air containing 60 ppm by volume of hydrogen sulfide was charged and blown at least once, and 5 L of dry air containing hydrogen sulfide of the same concentration was again filled therein to sufficiently replace the internal gas. Dry air containing 60 ppm by volume of hydrogen sulfide was prepared with a permeator (PD-1B, manufactured by Gastech Co., Ltd.) using commercially available compressed air.

Next, the initial hydrogen sulfide concentration C _0T (volume ppm) was measured using a detector tube (No. 4LL, manufactured by Gastech Co., Ltd.). Thereafter, light irradiation was started from outside the bag such that light having an ultraviolet intensity of 0.5 mW / cm ^{2 at} a wavelength of 365 nm was applied to the photocatalyst surface. The hydrogen sulfide concentration C _1T (volume ppm) in the bag after 4 hours was measured starting from that time. On the other hand, as a control experiment, a test in which the same operation as described above was carried out for 4 hours in a dark place was also performed. The initial concentration of hydrogen sulfide at that time was defined as C _0B (ppm by volume), and the concentration of hydrogen sulfide after 4 hours was defined as C _1B (ppm by volume).

In addition, a black light (FL20S / BL-B, manufactured by National Corporation) was used as a light source, and a UV integrated light meter, UIT-150, manufactured by Ushio Inc. was used to measure the light intensity at 365 nm.
The decomposition rate D _{1 of} hydrogen sulfide excluding adsorption is
D ₁ = {(C _0T −C _1T ) − (C _0B −C _1B )} / C _0T × 100 (%)
Defined by As D ₁ is large, it can be determined that the photocatalytic large.

(3) Weather resistance test (film weather resistance)
A portion of the film produced for the ink decolorization test was used for the weather resistance test. The weather resistance test was performed on the flat plate for 48 hours using a sunshine super long life weather meter WEL-SUN-HCH type manufactured by Suga Test Instruments Co., Ltd. According to JIS K 7350-4 (Plastic-exposure test method using a laboratory light source, open frame carbon arc lamp), using an I-type filter, black panel temperature 63 ± 3 ° C., water spraying time 18 ± 0.5 minutes / 60 minutes The test was performed under the following conditions.

The evaluation of the weather resistance was carried out by measuring the glossiness of the flat plate before and after being subjected to a sunshine super long life weather meter using GLOS CHECKER IG-320 manufactured by Horiba, Ltd., and determining the glossiness. Assuming that the glossiness of the film before the weather resistance test is BL ₀ (%) and the glossiness of the film after the weather resistance test is BL ₁ (%),
Gloss retention _{= BL 1 / BL 0 × 100} (%)
Was calculated by

(4) Evaluation of Mixed Crystal State In the present invention, XPS (X-ray photoelectron spectroscopy) is employed as a method for checking the mixed crystal state of the child particles. For details, see A.I. Yu. Stakheev et al, J. Mol. Phys. Chem. , 97 (21), 5668-5672 (1993).

Example 1
A gas containing 9.4 Nm ³ / hour of gaseous titanium tetrachloride having a concentration of 100% by volume (N means a standard state; the same applies hereinafter) and 0.25 Nm ³ / hour of gaseous silicon tetrachloride having a concentration of 100% by volume. After mixing, a mixed gas of 8 Nm ³ / hour of oxygen and 20 Nm ³ / hour of steam was preheated to 1,000 ° C. at 1,000 ° C., and a flow rate of 49 m / sec. It was introduced into the reaction tube at 60 m / sec.
In the reaction, gas was introduced such that the inner tube side of the coaxial parallel flow nozzle became a mixed gas of titanium tetrachloride and silicon tetrachloride. The inner diameter of the reaction tube was 100 mm, and the flow rate in the tube at a reaction temperature of 1,300 ° C. was a calculated value of 10 m / sec.

  After the reaction, cooling air is introduced into the reaction tube so that the high-temperature residence time in the reaction tube is 0.3 seconds or less, and then the ultrafine powder produced using a polytetrafluoroethylene bag filter is collected. did. The collected powder was heated in an oven in an air atmosphere at 500 ° C. for 1 hour to perform a dechlorination treatment.

The obtained ultrafine-particle mixed crystal oxide has a BET specific surface area of 24 m ² / g, an SiO ₂ content of 2.2 mass%, an average primary particle diameter of 0.06 μm calculated from the BET specific surface area, and a chlorine content of 0.01%. % By mass, and a titanium-oxygen-silicon bond was observed by XPS. This ultrafine mixed crystal oxide was used as a child particle.

On the other hand, 800 g of alumina balls having a diameter of 5 mm were put into a nylon container having a diameter of 12.5 cm. Here, 190 g of aluminum hydroxide (Heidilite (registered trademark) H-10C: average particle size of 85 μm) manufactured by Showa Denko KK and titanium oxide-silica composite fine particles (average particle size calculated from BET specific surface area) obtained by the above method 0.06 μm, SiO ₂ = 2.2% by mass). This was capped and ground and mixed at 50 revolutions per minute for 2 hours. The energy constant at this time is 3,000.

  After the pulverization and mixing, the processed product was observed with a scanning electron microscope. As a result, there were few free particles and most of the particles were composited. The aluminum hydroxide was used as a base particle (measured by laser diffraction / scattering particle size analysis. The average particle diameter to be obtained is about 60 μm and does not change much), and the titanium oxide-silica composite fine particles are formed on the surface of the base particles as child particles (the average particle diameter calculated from the BET specific surface area does not change). It was confirmed that composite particles supported as were obtained.

The composite particles thus obtained were formed into a film by the above-mentioned method, and an ink decoloring test was performed. As a result, the magenta color was almost completely erased. The color erasure test was performed in the dark for the same time, but no color erasure was observed. Therefore, it was confirmed that the decoloration in the above-described ink decolorization test was due to the photocatalytic effect. The gloss retention of the obtained film was as good as 90%. The decomposition rate D ₀ excluding the adsorption of hydrogen sulfide was 40%.

Example 2:
800 g of alumina balls having a diameter of 5 mm were put into a nylon container having a diameter of 12.5 cm. Here, 190 g of aluminum hydroxide manufactured by Showa Denko KK (Heidilite HS-320: average particle diameter 9 μm measured by laser diffraction / scattering particle size analysis) and 10 g of the titanium oxide-silica composite fine particles used in Example 1 were used. I put it in. This was capped and pulverized and mixed at 50 rpm for 30 minutes. The energy constant at this time is 750.

  After the pulverization and mixing, the processed product was observed with a scanning electron microscope. As a result, there were few free particles and most of the particles were composited. The aluminum hydroxide was used as a base particle (measured by laser diffraction / scattering particle size analysis. The average particle size of the composite particles does not change significantly), and the titanium oxide-silica composite fine particles are supported on the surface of the base particles as child particles (the average particle size calculated from the BET specific surface area does not change). It was confirmed that particles were obtained.

The composite particles thus obtained were formed into a film by the above-mentioned method, and an ink decoloring test was performed. As a result, the magenta color was almost completely erased. The color erasure test was performed in the dark for the same time, but no color erasure was observed. Therefore, it was confirmed that the decoloration in the above-described ink decolorization test was due to the photocatalytic effect. The gloss retention of the obtained film was as good as 80%. The decomposition rate D ₀ excluding the adsorption of hydrogen sulfide was 60%.

Example 3
800 g of alumina balls having a diameter of 5 mm were put into a nylon container having a diameter of 12.5 cm. 190 g of spherical nylon powder KG-10 (average diameter 10 μm, melting point 165 ° C.) manufactured by Toray Industries, Inc. and 10 g of the titanium oxide-silica composite fine particles used in Example 1 were added thereto. This was capped and mixed at 50 revolutions per minute for 8 hours. The energy constant k at this time is 12,000.

  After the pulverization and mixing, the processed product was observed with a scanning electron microscope. As a result, there were few free particles, most of the particles were complexed, and nylon was used as a base particle (measured by laser diffraction / scattering particle size analysis. The average particle size does not change significantly), and the composite particles in which the titanium oxide-silica composite fine particles are supported on the surface of the base particles as child particles (the average particle size calculated from the BET specific surface area does not change) are It was confirmed that it was obtained.

The composite particles thus obtained were formed into a film by the above-mentioned method, and an ink decoloring test was performed. As a result, the magenta color was almost completely erased. The color erasure test was performed in the dark for the same time, but no color erasure was observed. Therefore, it was confirmed that the decoloration in the above-described ink decolorization test was due to the photocatalytic effect. The gloss retention of the obtained film was as good as 85%. The decomposition rate D ₀ excluding the adsorption of hydrogen sulfide was 55%.

Example 4:
27 kg of calcium carbonate whiten B (average particle size 14 μm measured by laser diffraction / scattering particle size analysis) manufactured by Shiraishi Calcium Co., Ltd. was charged into Super Mixer SMG-100 (100 L in internal volume) manufactured by Kawata Corporation. Here, 3 kg of the titanium oxide-silica composite fine particles used in Example 1 were charged, and the lid was closed. A complexing treatment was performed at room temperature at 1500 rpm for 3 minutes. At this time, the energy constant k2 is 4500.

    Observation of the processed product with a scanning electron microscope after this complexing treatment revealed that free particles were small and most of the particles were complexed, and calcium carbonate was converted into mother particles (measured by laser diffraction / scattering particle size analysis. The average particle size does not change significantly), and the titanium oxide-silica composite particles are formed as small particles (the average particle size calculated from the BET specific surface area does not change) on the surface of the base particles. It was confirmed that particles were obtained.

The composite particles thus obtained were formed into a film by the above-mentioned method, and an ink decoloring test was performed. As a result, the magenta color was almost completely erased. The color erasure test was performed in the dark for the same time, but no color erasure was observed. Therefore, it was confirmed that the decoloration in the above-described ink decolorization test was due to the photocatalytic effect. The gloss retention of the obtained film was as good as 85%. The decomposition rate D ₀ excluding the adsorption of hydrogen sulfide was 50%.

Example 5:
1.5 kg of calcium carbonate whiten B (average particle diameter 14 μm measured by laser diffraction / scattering particle size analysis) manufactured by Shiraishi Calcium Co., Ltd. was charged into a paint shaker (internal volume 5 L) of Asada Tekko Co., Ltd. Here, 200 g of the titanium oxide-silica composite fine particles used in Example 1 were charged, and the lid was closed. The complexing treatment was performed at room temperature for 5 minutes. The energy constant k3 at this time is about 600.

    Observation of the processed product with a scanning electron microscope after this complexing treatment revealed that free particles were small and most of the particles were complexed, and calcium carbonate was converted into mother particles (measured by laser diffraction / scattering particle size analysis. The average particle size does not change significantly), and the titanium oxide-silica composite particles are formed as small particles (the average particle size calculated from the BET specific surface area does not change) on the surface of the base particles. It was confirmed that particles were obtained.

The composite particles thus obtained were formed into a film by the above-mentioned method, and an ink decoloring test was performed. As a result, the magenta color was almost completely erased. The color erasure test was performed in the dark for the same time, but no color erasure was observed. Therefore, it was confirmed that the decoloration in the above-described ink decolorization test was due to the photocatalytic effect. The gloss retention of the obtained film was as good as 80%. The decomposition rate D ₀ excluding the adsorption of hydrogen sulfide was 65%.

Comparative Example 1:
27 kg of calcium carbonate whiten B (average particle size 14 μm measured by laser diffraction / scattering particle size analysis) manufactured by Shiraishi Calcium Co., Ltd. was charged into Super Mixer SMG-100 (100 L in internal volume) manufactured by Kawata Corporation. Here, 3 kg of the titanium oxide-silica composite fine particles used in Example 1 were charged, and the lid was closed. A composite treatment was performed at room temperature for 200 revolutions / minute for 30 seconds. At this time, the energy constant k2 is 100.

After this treatment, the processed product was observed with a scanning electron microscope, and no difference from a mere mixed powder was observed.

These particles were formed into a film by the above-mentioned method, and an ink decoloring test was performed. As a result, the magenta color was not lost. The gloss retention of the obtained film was 40% or less, which was very poor. It is considered that the titania-silica particles were in direct contact with the resin because the composite was not formed, and the weather resistance was deteriorated by the photocatalytic action.
Comparative Example 2:
27 kg of calcium carbonate whiten B (average particle size 14 μm measured by laser diffraction / scattering particle size analysis) manufactured by Shiraishi Calcium Co., Ltd. was charged into Super Mixer SMG-100 (100 L in internal volume) manufactured by Kawata Corporation. Here, 3 kg of the titanium oxide-silica composite fine particles used in Example 1 were charged, and the lid was closed. A complexing treatment was performed at room temperature at 1500 rpm for 45 minutes. The energy constant k2 at this time is 67500.

After this treatment, the object was firmly fixed on the surface of the supermixer. This is due to the powder being firmly agglomerated by excessive processing. Such powders are difficult to disintegrate and are unsuitable for use.

Claims (19)

The small particles are titanium oxide-silica composite fine particles having an average particle size of 0.02 μm to 0.5 μm in terms of BET specific surface area, and the small particles are average particles measured by a laser diffraction / scattering particle size analysis method. Composite particles supported on large particles having a diameter of 2 to 200 μm. The composite particles according to claim 1, wherein the large particles are spherical resin particles having a melting point of 150 ° C or higher. The composite particles according to claim 1, wherein the large particles are hydroxides, oxides, or carbonates containing at least one selected from the group consisting of Al, Mg, Ca, and Si. The composite particles according to any one of claims 1 to 3, wherein the proportion of silica in the small particles is 0.5% by mass or more and less than 50% by mass. The composite particles according to any one of claims 1 to 4, wherein a ratio of the small particles to the large particles is 0.5% by mass or more and less than 40% by mass. The material containing large particles and small particles is dry-mixed by a ball mill, and the energy constant k of the dry-mixing is such that the total mass of the particles to be mixed is wp (g), the media mass is wm (g), and the inner diameter of the ball mill container is d ( m), the number of rotations is n (rpm), and the mixing time is t (minutes),
k = (wm / wp) × d × n × t k represented by the following formula (1) is 50 or more and 50,000 or less, and the composite particle according to any one of claims 1 to 5 is produced. Method. In a powder processing apparatus of a type that mixes, grinds, and agitates a material containing large particles and small particles by rotation of a blade, when the rotation speed of the blade is n (rpm) and the mixing time is t (minute),
k2 = n × t The method for producing composite particles according to any one of claims 1 to 5, wherein k2 represented by the relationship represented by the expression (2) is 250 or more and 50,000 or less. In a powder processing apparatus of a type in which materials containing large particles and small particles are mixed, crushed and stirred by shaking, when the number of shaking (times / minute) is n and the mixing time is t (minutes),
k3 = n × t
The method for producing composite particles according to any one of claims 1 to 5, wherein k3 represented by the following relationship is 50 or more and 50,000 or less. An organic polymer composition comprising the composite particles according to any one of claims 1 to 5 in an amount of 0.01 to 80% by mass based on the total mass of the composition. The organic polymer composition according to claim 9, wherein the organic polymer of the organic polymer composition is at least one resin selected from the group consisting of a synthetic thermoplastic resin, a synthetic thermosetting resin, and a natural resin. . The organic polymer composition according to claim 9 or 10, wherein the organic polymer composition is a compound. The organic polymer composition according to claim 9 or 10, wherein the organic polymer composition is a masterbatch. A molded article obtained by molding the organic polymer composition according to any one of claims 9 to 12. A coating agent comprising the composite particles according to any one of claims 1 to 5. A paint comprising the composite particles according to claim 1. A structure having on its surface the composite particles according to any one of claims 1 to 5. A cosmetic comprising the composite particles according to any one of claims 1 to 5. A fiber comprising the composite particle according to any one of claims 1 to 5. A film comprising the composite particles according to claim 1.