JP2005313055A - Functional dispersion - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a functional dispersion capable of exerting a photocatalytic performance of a photocatalyst thoroughly without a deterioration in the base material and functional products in various forms processed with the dispersion, having antibacterial, antifouling and gas-decomposing properties and causing no discoloration or deterioration. <P>SOLUTION: The dispersion contains a compound oxide type niobium-titania photocatalyst of a niobium content of 0.1-25 mass%, described hereafter as titania type photocatalyst. The titania type photocatalyst is porous with an average particle size of 0.05-10 μm, an average pore diameter of 3-80 nm and a diameter of crystals of 5-1,000 nm. The titania type photocatalyst has practically no Lewis acid sites. Functional processed products using the functional dispersion containing the titania type photocatalyst are also provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention includes a functional dispersion containing a photocatalyst that is less likely to be discolored by heat and ultraviolet rays with respect to a substrate, and fibers, nonwoven fabrics, filters, films, paints, papers processed using this functional dispersion, The present invention relates to various functional processed products such as molded products.

In recent years, the demand for comfortable living has increased rapidly, especially photocatalytic processing of wallpaper, fibers, filters, etc. processed with paints and dispersions containing photocatalysts with excellent antibacterial, gas decomposability and antifouling properties. The product has received much attention. However, the coating material in which the titania photocatalyst is dispersed is not suitable for use because it has a defect such as discoloration or deterioration when irradiated with ultraviolet rays after application. In addition, when a functional dispersion containing a photocatalyst is used to process a film, a filter, a non-woven fabric, or the like, or when irradiated with ultraviolet rays or the like, there are disadvantages such as discoloration or deterioration.
The cause of these discoloration and deterioration is the excessive photocatalytic action of titania, and it is the same principle that decomposes various malodorous gases and organic stains in water. It is thought that the action is working.

As a method for improving discoloration and deterioration of a substrate such as a resin by these titania photocatalyst dispersions, a method for improving the titania surface and interface has been proposed. For example, the photocatalyst is supported inside the porous particles such as silica and zeolite or between the layers of the layered compound to reduce the contact area with the base material, thereby reducing poisoning (for example, Patent Document 1 and Patent Document 2). In addition, there is an attempt to devise a method of reducing the contact area with the base material by coating the surface of the photocatalyst particles with porous ceramic (see, for example, Patent Document 4 and Patent Document 5, for example). Various devices that do not deteriorate are proposed.
When functional dispersions containing these photocatalysts are applied to or processed on a substrate, a slight improvement effect of the substrate deterioration is recognized, but a sufficient substrate deterioration suppression effect is not recognized, which is impossible for practical use. was there. Further, the photocatalytic performance was not exhibited without a sufficient amount of light irradiation, and no antifouling effect or gas decomposition was observed in the shade or indoors, but only the progress of deterioration of the substrate was observed.

A rutile or anatase type titania containing 0.1 to 5 wt% of niobium in terms of Nb ₂ O ₅ has been reported (see, for example, Patent Document 6).
A method for producing anatase-type titanium oxide has been reported in the presence of a compound that generates ammonia by thermal hydrolysis in an aqueous solution containing a metal component such as vanadium (see, for example, Patent Document 7). This patent document describes the use of group Vb of the periodic table containing niobium. However, those produced by this production method are used for catalyst carriers and the like.
The effect of adding Nb ₂ O ₅ on the electrical conductivity of a titanium oxide sintered body has been reported (for example, see Non-Patent Document 1). This report does not mention photocatalytic activity.

○ Prior literature
JP-A-11-33100 (Claims) JP 2000-355872 A (Claims) JP 2000-354768 A (Claims) JP 09-225319 A (Claims) JP 2001-286728 A (Claims) JP 09-267037 A (Claims) Japanese Patent Application Laid-Open No. 07-267641 (Claims) Masasuke Takada and three others, “Effects of Al 2 O 3 and Nb 2 O 5 on the electrical conductivity of TiO 2 sintered body”, Journal of Ceramic Industry Association, 1976, Vol. 84, No. 5, p 237-241

  The present invention is a functional dispersion that can fully exhibit the photocatalytic performance of the photocatalyst without degrading the substrate, and antibacterial, antifouling, or gas decomposability processed using this functional dispersion. It is an object of the present invention to provide functional products having various shapes that do not cause discoloration or deterioration.

As a result of intensive studies to solve the above problems, the present inventor has found that a dispersion containing a titania-based photocatalyst composed of a porous composite oxide having a specific composition solves the above problems, and the present invention. It came to complete. That is, the functional dispersion of the present invention is a dispersion containing a composite oxide type niobium-titania photocatalyst (referred to as a titania photocatalyst) having a niobium content of 0.1 to 20% by mass. Further, the titania-based photocatalyst is a porous one having an average particle diameter of 0.05 to 10 μm, an average pore diameter of 3 to 80 nm, and a crystallite diameter of 5 to 1000 nm. This titania-based photocatalyst has substantially no Lewis acid point.
And this invention is a functional processed product using the functional dispersion liquid containing a titania type photocatalyst.

The present invention will be described in detail below. “%” Represents mass%.
O Titania-based photocatalyst The composite oxide type niobium-titania-based photocatalyst contained in the functional dispersion of the present invention is titania containing niobium atoms. Further, it is a titania photocatalyst further containing a trivalent atom.

The niobium content in the titania-based photocatalyst is from 0.1 to 25%, preferably from 2 to 20%, more preferably from 3.5 to 18%, and from 4 to 17% due to excellent resin coloring reduction effect and photocatalytic effect. Is more preferable. This niobium content is the content of niobium atoms with respect to titanium atoms in the titania-based photocatalyst, and is represented by the following formula.
Niobium content = (niobium atom mass / (niobium atom mass + titanium atom mass)) × 100

In order to further improve the photocatalytic effect of the functional dispersion of the present invention, a trivalent atom can be contained in the titania-based photocatalyst in addition to the titanium atom and the niobium atom. Preferred examples of the trivalent atom include an aluminum atom, a cerium atom and an iron atom. More preferred as the trivalent atom are an aluminum atom and a cerium atom, and particularly preferred is an aluminum atom. The ratio of trivalent atoms in the titania photocatalyst is 0.01 to 20 mol%, preferably 0.2 to 19 mol%, more preferably 1 to 18 mol%, relative to the titanium atom in the titania photocatalyst. ˜15 mol% is most preferred. This calculation method of mol% was calculated using the following formula from the molar value of trivalent atoms in the titania photocatalyst.
Mol% of trivalent atoms in titania-based photocatalyst =
(Mole value of trivalent atom / (Mole value of titanium atom + Mole value of trivalent atom)) × 100

  The titania-based photocatalyst used in the functional dispersion of the present invention needs to be a complex oxide, not a mixture of niobium atoms, trivalent atoms, etc. with titanium oxide. Moreover, even if components other than titanium atoms, niobium atoms, and trivalent atoms are contained in the titania-based photocatalyst, they may be in a range that does not greatly affect the effects of the present invention.

  The titania-based photocatalyst contained in the functional dispersion in the present invention is a porous composite oxide, and examples of the shape of the appearance include a disc-like shape in which the central portion is swollen on both sides and an irregular shape.

  The titania-based photocatalyst has an average particle size of 0.05 to 10 μm, preferably 0.15 to 8 μm, and more preferably 0.3 to 5 μm in consideration of dispersibility.

  The confirmation of the porosity in the titania photocatalyst was determined from the hysteresis of the nitrogen adsorption / desorption amount when the nitrogen relative pressure mixed with helium was changed.

In order to obtain an excellent photocatalytic effect in the functional dispersion in which the titania photocatalyst is dispersed, the pore volume of the titania photocatalyst is 0.05 to 10 cm ³ / g, preferably 0.1 to ⁵ cm ^3. / G, more preferably 0.3 to ⁵ cm ³ / g. Moreover, the average pore diameter of the titania photocatalyst is 3 to 80 nm, preferably 5 to 50 nm, and more preferably 6 to 40 nm.

  The crystallite diameter of the titania photocatalyst used in the functional dispersion of the present invention is preferably 5 to 1000 nm, more preferably 7 to 500 nm, and particularly preferably 50 to 300 nm. The crystallite size of the titania photocatalyst can be obtained by precisely separating the powder X-ray diffraction pattern of the titania photocatalyst and calculating by the Rietveld method, or observing with a transmission electron microscope. If the crystallite diameter of the titania-based photocatalyst is too large, the specific surface area may decrease, and the photoreaction efficiency as the functional dispersion may decrease, and the processability may decrease. Even if the crystallite size is too small, the particles are aggregated when the crystals are dispersed in the functional dispersion, and the secondary particle size becomes large, which may cause poor dispersion.

Titania-based photocatalyst used in the functional dispersion of the present invention is the absorption peak be performed pyridine adsorption treatment from 1420 cm ^-1 from 1460 cm ^-1 and 1590 cm ^-1 in a wavelength of 1620 cm ^-1 is not observed. A titania photocatalyst having no absorption peak at a specific wavelength even when such pyridine adsorption treatment is performed is a photocatalyst having a low Lewis acid point that is considered to cause resin degradation. That is, the titania photocatalyst used in the functional dispersion of the present invention has substantially no Lewis acid point. The Lewis acid point in the titania photocatalyst indicates a place that acts as a Lewis acid in the titania photocatalyst. In the present invention such a place, when measuring the infrared absorption spectrum by performing pyridine adsorption treatment, mainly absorption peak and about 1605 ^-1 between 1460 cm ^-1 from 1420 cm ^-1 to around about 1440Cm ^-1 The absorption peak between 1420 cm ^-1 and 1460 cm ^-1 is recognized as compared with that not subjected to pyridine adsorption treatment.

  The crystal form of the titania-based photocatalyst in the present invention is most preferably composed of only brookite-type crystals because it hardly causes discoloration of the substrate, and the brookite-type crystals partially include anatase-type crystals and / or rutile-type crystals. It may be an anatase type crystal and / or a rutile type crystal as long as it does not substantially have a Lewis acid point, and an amorphous material substantially not having a Lewis acid point may be used. It may be included.

○ Manufacturing method of titania-based photocatalyst The manufacturing method of titania-based photocatalyst used in the functional dispersion of the present invention comprises a titanium aqueous solution (for example, titanium sulfate or titanyl sulfate dissolved in water) and a niobium aqueous solution (for example, niobium oxide hydrate). And a mixture solution thereof dissolved in water using oxalic acid or the like) is heated at 200 ° C. or lower. Alternatively, a titania-based photocatalyst can be obtained by subjecting a mixed solution of an aqueous titanium solution, an aqueous niobium solution, and an aqueous solution of a trivalent atomic salt to 200 ° C. or less. At this time, a compound that generates ammonia by heating such as urea or hexamethylenetetramine may be mixed.
The temperature of this heating treatment is more preferably between 50 and 150 ° C, and further preferably between 60 and 105 ° C. When the temperature of the heating treatment is less than 50 ° C., sufficient crystals are difficult to obtain, and the titania photocatalyst of the present invention may not be obtained. When the temperature of the heating treatment exceeds 200 ° C., the titania photocatalyst of the present invention may not be obtained.
The heating time for obtaining the titania photocatalyst may be a time for precipitation of the titania photocatalyst, for example, 0.5 to 300 hours, preferably 1 to 100 hours, and more preferably 1 to 10 hours.

  When a niobium aqueous solution is prepared using oxalic acid, the amount of this compound added to niobium pentoxide is preferably added in an equimolar to 10-fold molar amount with respect to niobium atoms, and more preferably in an excess of equimolar to 5-fold molar amount.

  The aqueous solution of the trivalent atomic salt is obtained by dissolving a salt of a trivalent atom in water. For example, a trivalent atomic salt solution of nitric acid or a trivalent atomic salt solution of sulfuric acid can be used. Specific examples include aluminum nitrate, cerium nitrate, iron nitrate, aluminum sulfate, cerium sulfate, and iron sulfate.

  When producing the titania-based photocatalyst contained in the functional dispersion of the present invention, the pH of a mixed liquid of an aqueous titanium solution and an aqueous niobium solution may be adjusted using an alkali. Further, after the titania photocatalyst is precipitated, the titania photocatalyst may be washed by adjusting the pH of the solution using an alkali.

  Alkali metal hydroxides, alkaline earth metal hydroxides, alkali metal carbonates, alkaline earth metal carbonates, alkali metal hydrogen carbonates, alkaline earth metal hydrogen carbonates are used as alkalis to be used. Examples thereof include a salt, an aqueous ammonia solution, ammonium carbonate, ammonium acetate, and hexamethylenetetramine, and these may be used alone or in combination.

  Among these alkali metals, lithium, sodium, and potassium are preferable, and lithium is particularly preferable. Among the alkaline earth metals, calcium, strontium, and barium are preferable, and calcium is more preferable. Among alkaline earth metals and alkali metals, alkali metals are preferred. Moreover, as other alkalis, ammonium carbonate, hexamethylenetetramine and the like are preferable.

  In order to produce a niobium-containing titania-based photocatalyst (not containing a trivalent atom) used in the functional dispersion of the present invention, it is necessary to heat-treat the obtained crystal at a temperature of 550 ° C. or higher. Moreover, it is preferable that the said heat processing is 1200 degrees C or less. In this heat treatment, the obtained crystals may be precipitated as they are in an aqueous solution, or may be treated by filtering the crystals by filtration or the like, or by drying the filtered crystals. The temperature for this heat treatment is preferably 550 to 1000 ° C, more preferably 600 to 900 ° C, and particularly preferably 700 to 850 ° C. When the temperature of the heat treatment is 550 ° C. or lower, the catalytic performance of the titania-based photocatalyst may be reduced. For this reason, the photocatalytic performance of the functional dispersion may be reduced. The heat treatment temperature should not be directly inserted into a baking furnace or the like having a temperature of 550 ° C. or higher, but gradually heated from room temperature to the heat treatment temperature. The heating rate is preferably 250 ° C. or less per hour.

  In order to produce a titania-based photocatalyst containing a trivalent atom and niobium used in the functional dispersion of the present invention, it is necessary to heat-treat the obtained crystal at a temperature of 300 ° C. or higher. Moreover, it is preferable that the said heat processing is 900 degrees C or less. In this heat treatment, the obtained crystals may be precipitated as they are in an aqueous solution, or may be treated by filtering the crystals by filtration or the like, or by drying the filtered crystals. The temperature for this heat treatment is preferably 300 to 850 ° C, more preferably 330 to 800 ° C, and particularly preferably 350 to 750 ° C. When the temperature of the heat treatment is 300 ° C. or lower, the catalytic performance of the titania photocatalyst may be reduced. For this reason, the photocatalytic performance of the functional dispersion may be reduced. The heat treatment temperature should not be directly inserted into a baking furnace having a temperature of 300 ° C. or higher, but gradually heated from room temperature to the heat treatment temperature. The heating rate is preferably 200 ° C. or less per hour.

  The heat treatment time is 1 to 100 hours, preferably 1 to 40 hours, and more preferably 2 to 20 hours. When this heat treatment time is shorter than 1 hour, sufficient crystallinity cannot be obtained and sufficient photocatalytic performance may not be obtained. As the heat treatment time becomes longer, crystallization and composition homogenization proceed, and higher photocatalytic performance and substrate deterioration suppressing performance can be obtained. However, when the heat treatment time becomes longer than 100 hours, it becomes less economical. In addition, the crystal particles may grow due to the progress of sintering, and the specific surface area may be reduced, which may make it difficult to obtain sufficient photocatalytic performance.

  A functional dispersion can be obtained by dispersing the titania photocatalyst thus obtained in a solvent. There is no restriction | limiting in particular as a method of disperse | distributing a titania type photocatalyst. For example, a functional dispersion can be prepared by blending a dispersion medium or the like with a high-concentration titania-based photocatalyst (making a high-concentration paste). Further, the functional dispersion can be prepared by diluting the functional dispersion with a dispersion medium, a diluent, or a binder component.

About compounding agent The titania photocatalyst contained in the functional dispersion of the present invention decomposes aldehyde gases such as formaldehyde and acetaldehyde in the atmosphere, organic solvent gases such as toluene, etc. The substance can be decomposed. In such a case, it is possible to further enhance the decomposition performance by further blending an adsorbing substance such as activated carbon or silica gel into the functional dispersion or blending another photocatalyst.
Examples of the compounding agent that can be incorporated into the functional dispersion of the present invention include substances that physically adsorb compounds and substances that adsorb compounds chemically. Examples of the substance that physically adsorbs a compound include porous substances such as activated carbon and zeolite, and ultrafine particles such as aerosil. When the specific surface area of the substance that physically adsorbs the compound is small, the specific surface area of 5 m ² / g or more is preferable because the amount of adsorption of the compound decreases. Examples of the substance that is chemically adsorbed include an ion exchanger, a substance that chemically reacts with the compound to be adsorbed, or a substance that carries a substance that chemically reacts with the compound to be adsorbed. Examples of the substance that chemically reacts with the compound to be adsorbed include amine compounds that cause a Schiff reaction with aldehydes such as formaldehyde and acetaldehyde. Examples of the substance carrying the substance that chemically reacts include porous silica and zeolite, and an inorganic substance having a cation exchange property.

  The compounding agent blended in the functional dispersion of the present invention may be a single compounding agent or a plurality of compounding agents. There is no restriction | limiting in particular in each compounding ratio, It can change suitably with the environment to be used.

The decomposition target such as bad odor in the living environment is hardly a single component, and a plurality of gases and a plurality of solutions coexist. Therefore, it is preferable to use a plurality of compounding agents suitable for the decomposition and adsorption of various target components.
The case of malodor is given as an example of one of a plurality of gases to be decomposed. The main gas of sweat odor is said to be ammonia, acetic acid, isovaleric acid and nonenal which is an unsaturated aldehyde. Therefore, as a deodorant for sweat odor, a combination of a deodorant suitable for basic gas, a deodorant suitable for acidic gas, and a deodorant suitable for aldehyde gas should be used in combination. Is preferred. As an example of this compounding agent, at least one compound selected from tetravalent metal phosphates and aluminum silicates which are insoluble or hardly soluble in water, and has a primary amino group in the molecule. At least one selected from a compound carrying a compound, a hydrotalcite compound, a calcined hydrotalcite, a hydrated zirconium oxide, a zirconium oxide, and a hydrated titanium oxide. It is preferable to use together.

  Deodorant suitable for basic gas, deodorant suitable for acidic gas, deodorant suitable for aldehyde gas, deodorant suitable for sulfur gas, and titania It is preferable to use a functional dispersion in combination with a system photocatalyst. For tobacco odor, deodorant suitable for basic gas, deodorant suitable for acid gas, deodorant suitable for aldehyde gas, deodorant suitable for sulfur gas, and titania It is preferable to use a functional dispersion in combination with a system photocatalyst. The sweat odor, excretion odor, and tobacco odor are different in the mixing ratio of basic gas, acid gas, aldehyde gas, and sulfur-based gas. From this, these deodorizers for sweat odor, excretion odor, and tobacco odor are suitable for each odor component mixed at a suitable ratio.

  For example, as a deodorant used in combination with a titania-based photocatalyst, a product carrying a compound having a primary amino group in the molecule; a tetravalent metal phosphate that is insoluble or hardly soluble in water; copper, Tetravalent metal phosphate that is insoluble or sparingly soluble in water carrying at least one metal ion selected from zinc and manganese; aluminum silicate; zinc silicate; zinc oxide; hydrotalcite compound; Site burned product; hydrated zirconium oxide; zirconium oxide and hydrated titanium oxide. As the deodorant used in combination, one kind or a plurality of kinds may be used.

  The solid content of the titania photocatalyst or the mixture of the titania photocatalyst and the blend in the functional dispersion of the present invention is preferably 0.1 to 70%, more preferably 0.5 to 60%, and particularly preferably 1 to 55% is preferred. When the solid content in the functional dispersion is 0.1% or less, the dispersion stability may be deteriorated because the viscosity of the dispersion is low. When the solid content in the functional dispersion exceeds 70%, the viscosity of the dispersion becomes too high, which may be difficult to produce, and the product handleability may be deteriorated. Further, in the mixture of the titania photocatalyst and the blend, the titania photocatalyst is preferably contained in an amount of 10 to 90%, more preferably 20 to 85%, and particularly preferably 30 to 80%. Preferably it is.

Production method of functional dispersion Any of the methods for producing a dispersion of inorganic powder can be used for the production of the functional dispersion of the present invention. For example, the functional dispersion of the present invention may be produced by adding a titania photocatalyst to a dispersion medium such as water and a polymer dispersant, and stirring and dispersing with a sand mill, a disper, or a ball mill. In addition, for example, the functional dispersion of the present invention can be produced by adding a dispersion medium such as water, a polymeric dispersant and a titania photocatalyst, a surfactant, an antifoaming agent, an antiseptic, a viscosity modifier, a leveling agent, Necessary to be selected from binder components, antibacterial agents, fungicides, flame retardants, antioxidants, matting agents, rust inhibitors, coupling agents, metal powders, glass powders, fragrances, deodorants, and pigments And may be stirred and dispersed by a sand mill, a disper, or a ball mill.

-Dispersion medium The dispersion medium in this invention can be used without a restriction | limiting, Preferably it has water solubility and hydrophilicity. Specifically, examples of the protic solvent include water and alcohol, and examples of the aprotic solvent include dimethylformamide, dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, and acetone. Among these, a preferred dispersion medium is water.

Polymeric dispersant The polymeric dispersant used in the present invention preferably contains at least a copolymer (resin) containing an acidic functional group. The basic skeleton of the polymer dispersant is preferably composed of an ester chain, a vinyl chain, an acrylic chain, an ether chain and / or a urethane chain, and a part of hydrogen atoms in the molecule is substituted with a halogen atom. It may be. Among these, acrylic resins, polyester resins, and alkyd resins are preferable, and acrylic resins and polyester resins are particularly preferable. Examples of the acidic functional group include a carboxyl group, a sulfone group, and a phosphoric acid group, and among them, a phosphoric acid group is preferable. The acid value of the copolymer (resin) containing an acidic functional group is preferably 5 to 150 mgKOH / g. If the acid value is less than 5 mgKOH / g, the dispersion stability may be lowered, which is not preferable. When the acid value exceeds 150 mgKOH / g, sufficient dispersion stability of the particles may not be obtained. The acidic functional groups may be arranged at random in the resin molecule, but those having an acidic functional group arranged at the terminal portion of the molecule due to the block or graft structure are likely to have a dispersion-stabilized structure. Therefore, it is preferable. This molecular weight is preferably in the range of 500 to 100,000 in terms of mass average molecular weight, more preferably 750 to 10,000. If the molecular weight is less than 500, the dispersion effect may be lowered, which is not preferable, and if it exceeds 100,000, agglomeration and an increase in viscosity may occur.
The polymer dispersant used in the present invention may be a single type or a plurality of types.

  In the present invention, the preferred amount of addition of the polymeric dispersant is 0.1 to 15 parts by mass, and more preferably 1 to 10 parts by mass with respect to 100 parts by mass of the solid content such as titania photocatalyst and compounding agent. Yes, particularly preferably 2 to 8 mass. If the amount of the polymeric dispersant added is less than 0.1 parts by mass, the dispersion may not be sufficient and reaggregation may occur. On the other hand, when the amount of the polymeric dispersant added is more than 15 parts by mass, the dispersibility may be lowered (a depletion phenomenon) due to the influence of an excessive dispersant, such being undesirable.

Surfactant In the present invention, any of amphoteric surfactants, anionic surfactants, and nonionic surfactants may be used as the surfactant.
Examples of amphoteric surfactants include those having a carboxylate, sulfate, sulfonate, and phosphate ester salt as the anion moiety, and an amine salt and a quaternary ammonium salt as the cation moiety. Examples of alkylbetaines include lauryl betaine, stearyl betaine, cocoamidopropyl betaine, and 2-undecyl-hydroxyethylimidazolium betaine, and amino acid types include lauryl-β-alanine, stearyl-β-alanine, lauryl diamine. Examples include (aminoethyl) glycine, octyldi (aminoethyl) glycine, and dioctyl (aminoethyl) glycine salts.
Examples of anionic surfactants include higher alcohol sulfates, alkylbenzene sulfonates, and aliphatic sulfonic acids.
Examples of nonionic surfactants include polyethylene glycol alkyl ester type, alkyl ether type, and alkylphenyl ether type.
The surfactant used in the present invention may be a single type or a plurality of types.

○ Antifoaming agent In the present invention, the antifoaming agent has a foam-breaking property, a foam-suppressing property, and a defoaming property, but any one may be used. As an example of foam breaking property, a polysiloxane solution can be mentioned.

Preservative In the present invention, any known preservative can be used, and examples thereof include phenol, organic tin, organic iodine, thiazole, imidazole, and nitrile derivatives.

Viscosity modifier Any known viscosity modifier can be used in the present invention. For example, cellulose thickeners such as methylcellulose, carboxymethylcellulose, methylhydroxycellulose, methylhydroxypropylcellulose, hydroxyethylcellulose; natural polysaccharides such as gum arabic, trangan gum, guar gum; various polyacrylamide polymers; polyethylene oxide; polyvinyl alcohol and so on.

○ Leveling agent Any known leveling agent may be used in the present invention. For example, cellosolv type such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether; polypropylene glycol monomethyl ether, polypropylene glycol monoethyl ether, propylene glycol ether type; carbinate type such as diethylene glycol monoethyl ether, diethylene glycol monobutyl ether Triglycol ethers such as triethylene glycol monomethyl ether and tripropylene glycol monomethyl ether; funnel oil; dicyandiamide; urea and the like.

  The functional dispersion of the present invention can be mixed with a binder resin that is usually used for surface treatment of fibers such as acrylic acid and urethane, nonwoven fabrics, and sheets. At this time, the solid content of the titania photocatalyst and the like in the functional dispersion containing the binder resin and the titania photocatalyst is preferably 5 to 50%, more preferably 7 to 45%, and particularly preferably 10 to 40%. The mixing ratio between the solid content of the titania photocatalyst and the binder resin is preferably 10 to 300 parts by mass, and more preferably 15 to 250 parts by mass with respect to 100 parts by mass of the solid content of the titania photocatalyst. Particularly preferred is 20 to 200 mass. If the resin solid content is less than 10 parts by mass, the titania photocatalyst may fall off because there is a fear that the adhesive strength when adhering to a fiber, nonwoven fabric, sheet, etc. using a functional dispersion containing a binder resin may not be sufficient. As a result, the photocatalytic (decomposition) performance may be deteriorated. Moreover, when the resin solid content exceeds 300 parts by mass, the titania photocatalyst may be covered with the resin when processed into a fiber, a nonwoven fabric, a sheet or the like, so that the photocatalytic performance may not be sufficiently exhibited, which is not preferable.

Application The functional dispersion containing a photocatalyst of the present invention can be used for various products that require gas decomposability such as deodorization, antibacterial properties, and antifouling properties.
For example, the titania-based photocatalyst can be attached to the base material by dipping these base materials in a processing liquid obtained by diluting the functional dispersion with water or the like, such as fibers, nonwoven fabrics, and sheets. Alternatively, a fiber produced by a wet spinning method such as an acrylic fiber can be processed into a fiber in which a titania-based photocatalyst is kneaded by adding the functional dispersion of the present invention to a solvent.
Specific applications include underwear, stockings, shirts, socks, futons, futon covers, cushions, blankets, carpets, curtains, sofas, car seats, air filters, wallpaper, various fibers, non-woven fabrics, and paper products. .
In addition, by mixing the functional dispersion of the present invention with a paint, a paint having photocatalytic properties (antifouling properties and gas decomposability) can be obtained, and a photocatalytic function can be easily imparted to the coated material. it can. Applicable objects include building exterior walls, roof exteriors, rooftops, window glass exteriors, window glass interiors, room walls, floors, ceiling surfaces, blinds, curtains, road protection walls and guardrails, tunnel interior walls , A reflecting surface of an illuminating lamp, a cover or an umbrella, an interior surface or an outer surface of a vehicle such as a passenger car, a bus or a train, a glass outer surface, a glass inner surface, and the like. It can also be applied to furniture and household electrical appliances, doors and door knobs, various dishes and utensils, tables, cupboards, walls, inner and outer surfaces and parts of dishwashers, washing machines and vacuum cleaners, pet supplies and animal breeding There are parts that are anxious about odors such as houses and baskets, parts that are anxious about the propagation of germs such as waterways and drains, parts that are anaerobic such as sinks and cutting boards, but odors and waste liquids, It can be used if it is a part of concern about the growth of various bacteria and the adhesion of dirt. In addition, toilets, walls, toilet seats or toilets; bathrooms, bathtubs, walls, or ceilings; storage tools, clogs, closets, chests, floor storage, rice bowls, cooler boxes, or trash cans; exterior materials, Partition, bran, shoji or floor; household appliances such as TV, video, stereo, cooler, stove, vacuum cleaner, washing machine, refrigerator, electric kettle, kotatsu, rice cooker, shaver, waste shaver or dryer; Cups, teacups or bowls as tableware; film or handles for window glass as automobiles, shift knobs; bicycles; hats, bags, watches, fishing rods or shoes as portable items; wastewater treatment equipment, septic tanks as purification equipment; Air purifier, water purifier or garbage disposal device; Pools, ornamental fish tanks, living aquariums or stones around ponds; or pet supplies such as pet kennels, kennels or bird cages as animal supplies, and a coating is formed on the surface or inner surface of these parts Etc.

  Moreover, what processed functional dispersion liquid by attaching to a filter etc. can be applied to an air purifier, an air conditioner, a humidifier, etc., for air purification, sick house measures, a water storage tank, etc. Further, by using it as a paint or a sheet in the drainage groove or the filtration part, it is difficult to get slimy and can be kept clean.

When functional dispersion liquid is attached and processed on fibers, it is difficult to get dirt and odor, and it suppresses the propagation of germs, so clothing such as lab coats and aprons, tents, bandages, swimsuits, fishing lines, Various uses such as fish nets are possible. Examples of clothing include uniforms, suits, socks, underwear, coats, jumpers, sweaters, trainers, shirts, trousers, kimonos, skirts, stockings or tights. Further, the bedding includes a futon, a pillow or a blanket, a curtain, a carpet, a mat, and a carpet.
Furthermore, when a functional dispersion is coated on a sheet or film, various uses such as a wrap, a garbage bag, a plastic house, a garment, a seal attached to the surface of a glass / mirror can be mentioned.

  What was processed using the functional dispersion liquid of this invention may be used by irradiating light with a black light or a fluorescent lamp. In particular, a processed product using the functional dispersion of the present invention may be used by irradiating light with a fluorescent lamp.

<Example>
Examples of the present invention will be described below, but the present invention is not limited thereto.

Preparation of working solution Titanyl sulfate was dissolved in pure water to prepare an aqueous solution having a titanium concentration of 0.5 mol / liter (titanium aqueous solution).
Niobium pentoxide and oxalic acid were dissolved in pure water to prepare an aqueous solution having a niobium concentration of 0.5 mol / liter (niobium aqueous solution).
Aluminum nitrate was dissolved in pure water to prepare an aqueous solution having an aluminum concentration of 0.5 mol / liter (aluminum aqueous solution).
Cerium nitrate was dissolved in pure water to prepare an aqueous solution having a cerium concentration of 0.5 mol / liter (cerium aqueous solution).
Hexamethylenetetramine was dissolved in pure water to prepare a 1 mol / liter aqueous solution (hereinafter referred to as HMT aqueous solution).
Urea was dissolved in pure water to prepare a 2 mol / liter aqueous solution (hereinafter referred to as urea aqueous solution).

Preparation of photocatalyst powder A 800 ml of an aqueous titanium solution and 200 ml of an aqueous niobium solution are placed in a flask and mixed. The mixture is warmed to 80 ° C. and stirred for 4 hours. Thereafter, the mixture was allowed to cool to room temperature, filtered, washed with pure water, dried at 120 ° C., and further heated at 600 ° C. for 4 hours to obtain Powder A.
Preparation of photocatalyst powder B In a flask, 500 ml of an aqueous titanium solution and 100 ml of an aqueous niobium solution are mixed, held at 80 ° C. for 2 hours, and then mixed with 400 ml of an aqueous urea solution. The mixture is warmed to 100 ° C. and stirred for 2 hours. Then, after cooling to room temperature, it filtered. This filtrate was washed with pure water, dried at 120 ° C., and further heated at 800 ° C. for 4 hours to obtain Powder B.
Preparation of photocatalyst powder C In a flask, 500 ml of an aqueous titanium solution, 100 ml of an aqueous niobium solution and 100 ml of an aqueous cerium solution are mixed, held at 80 ° C. for 2 hours, and then mixed with 400 ml of an aqueous HMT solution. The mixture is warmed to 100 ° C. and stirred for 2 hours. Then, after cooling to room temperature, it filtered. This filtrate was washed with pure water, dried at 120 ° C., and further heated at 400 ° C. for 4 hours to obtain powder C.
○ Preparation of photocatalyst powder D A 900 ml titanium aqueous solution and 100 ml niobium aqueous solution were mixed in a flask for 2 hours, and then heated to 80 ° C. for 2 hours. Then, after cooling to room temperature, it filtered. This filtrate was washed with pure water, dried at 120 ° C., and further heated at 800 ° C. for 4 hours to obtain Powder D.
Preparation of photocatalyst powder E In a flask, 500 ml of an aqueous titanium solution, 100 ml of an aqueous niobium solution and 100 ml of an aqueous aluminum solution are mixed and held at 80 ° C. for 2 hours. Then, after cooling to room temperature, it filtered. This filtrate was washed with pure water, dried at 120 ° C., and further heated at 700 ° C. for 4 hours to obtain Powder E.

Preparation of Comparative Photocatalyst Powder Commercially available titania (Ishihara Sangyo Co., Ltd., grade ST-01) was used as comparative powder A for high-purity anatase-type titania.
The ST-01 was held in an ammonia stream at 600 ° C. for 24 hours to obtain a nitrogen-substituted titania and comparative powder B.
As a silica-coated titania, a mask melon type titania (manufactured by Taihei Chemical Industry Co., Ltd.) was used as a comparative powder C.

○ Analysis of crystallinity, niobium content, average particle size, crystallite size Table 1 shows the results of identifying the crystal phase from the powder X-ray diffraction measurement data of powders A to E and comparative powders A to C. Table 1 also shows the niobium content by fluorescent X-ray, the average particle size by laser diffraction particle size distribution measurement, and the crystallite size by scanning electron microscope observation.

Porosity analysis and pore measurement Powder A was subjected to adsorption and desorption tests using a nitrogen gas multipoint BET measurement method using GEMINI (manufactured by Shimadzu Corporation). From the result of this hysteresis, it was found that the powder A was porous. The average pore diameter of the powder A was about 10 nm.
The same results were obtained for the other powders B to E.

○ Measurement of Lewis acid point in photocatalyst 5 mL of 1 mol / L pyridine aqueous solution was added to 0.01 g of powder A, and the mixture was shaken at room temperature for 30 minutes. Thereafter, powder A was filtered and washed with water, dried in the dark, and an infrared (IR) spectrum of 1400 to 1700 cm ⁻¹ was measured (pyr ⁺ ). The same processing was performed on powder B, powder C, comparative powder A, comparative powder B, and comparative powder C, and the IR spectrum was measured. Further, the IR spectrum was similarly measured (pyr ⁻ ) for those not subjected to pyridine adsorption treatment.
The IR spectrum was measured using an infrared absorption device (Impact 400D manufactured by Nicolet) equipped with an ATR accessory called “DuraScope ^™ ” (manufactured by SensIR Technology).
FIG. 1 shows the IR spectrum of the powder A, and FIG. 2 shows the IR spectrum of the comparative powder B.
As a result, the powder A, B, IR spectrum of the pyr ⁺ of C is about centered on 1440Cm ^-1 from 1420 cm ^-1 to around the absorption peak of about 1605 ^-1 1460 cm ^-1 from 1420 cm ^-1 to 1460 cm ^-1 Absorption peak was not recognized compared with the comparative powder. Therefore, titania photocatalyst used in the functional dispersion of the present invention, which does not have a distinct absorption peak at 1620 cm ^-1 be performed pyridine solution processing from 1420 cm ^-1 from 1460 cm ^-1 and 1590 cm ^-1 is there.

Preparation of dispersion containing photocatalyst Powder A was made into dispersant Disperbyk-180 (manufactured by Big Chemie Japan Co., Ltd., alkyl ammonium salt of a block copolymer containing a phosphate group. Acid value 94 mgKOH / g, amine value 94 mgKOH / g average molecular weight 1000). As this dispersion prescription, 2.3 parts by weight of the dispersant with respect to 100 parts by weight of water (4.6 parts by weight with respect to 100 parts by weight of the deodorant solid content), 50 parts by weight of powder A, the best preservative Side # 300 (manufactured by Dainippon Ink & Chemicals, Inc.) 0.3 parts by mass, defoamer Disperbyk-022 (by Big Chemie Japan Co., Ltd.) 0.2 parts by mass, thickener Metroose SH15000 (Shin-Etsu Chemical) 13 parts by mass of a 4% aqueous solution (manufactured by Co., Ltd.) was added and stirred for 20 minutes at 3000 rpm in a sand mill to obtain a titania-based photocatalyst containing dispersion A. The titania-based photocatalyst solid content in this dispersion was 30% by mass. The same operation was performed for powders B to E and comparative powders A to C, and titania-based photocatalyst-containing paste dispersions B to E and comparative dispersions A to C were obtained.

○ Deodorant Evaluation of Cotton Fabric Processed Using Deodorant-Containing Dispersion 10 parts by mass of titania-based photocatalyst-containing paste dispersion A (3 parts by mass as titania-based photocatalyst powder) with respect to 100 parts by mass of pure water ) And an acrylic binder (KB-4900, solid content 45% by mass, manufactured by Toagosei Co., Ltd.) was added to prepare Suspension A. The same operations were performed on the titania-based photocatalyst-containing paste dispersions B to E and comparative dispersions A to C to prepare suspensions.
These suspensions are dipped with 100% cotton fabric (material mass 100 g / m ² ), picked up with a drawing rate of 70%, dried at 150 ° C., and test cloths A to E and comparative test cloths A to C Obtained. This cotton fabric was cut into 20 cm × 20 cm from any three locations and placed in a bag (hereinafter referred to as a Tedlar bag) prepared using a polyvinyl fluoride film (made by US DuPont), and 3 L of air containing an acetaldehyde gas concentration of 14 ppm was injected. And allowed to stand under ultraviolet irradiation for 24 hours. The residual gas concentration in the Tedlar bag was measured using a gas detector tube (No. 92L manufactured by Gastec).
As a standing condition under ultraviolet irradiation, UV was irradiated at an intensity of 1 mW / cm ² . The results are shown in Table 2. “ND” indicates that acetaldehyde could not be detected.

○ Evaluation of discoloration of test cloth processed using deodorant-containing dispersion The discoloration of each test cloth after the deodorization test in Example 2 was examined visually. The results are shown in Table 3.

Deodorant evaluation of cotton fabric processed using deodorant-containing dispersion: Visible light irradiation Test cloths A to E and comparative test cloths A to C prepared in Example 2 are 30 cm × 30 cm from arbitrary three locations. Was put in a Tedlar bag, 3 L of air containing an acetaldehyde gas concentration of 14 ppm was injected, and allowed to stand under visible light irradiation for 24 hours. The residual gas concentration in the Tedlar bag was measured using a gas detector tube (No. 92L manufactured by Gastec). However, a fluorescent lamp (Toshiba Life Tech / illuminance 2000 LUX) was used as the light source.
The results are shown in Table 4. “ND” indicates that acetaldehyde could not be detected.

  From the results of Examples 2 to 4, Dispersions A to E have a photocatalyst and are superior in resistance to discoloration due to ultraviolet irradiation compared to Comparative Dispersions A to C.

Preparation of photocatalyst-containing paint Powder A is added in an amount of 5 parts by mass with respect to 100 parts by mass of a commercially available paint (Sekipe Co., Ltd., Happiouresh, Egg White), stirred at 3000 rpm for 20 minutes in a sand mill, and containing a titania-based photocatalyst. Test paint A was obtained. The powders B to E and the comparative powders A to C were similarly processed to obtain test paints B to E and comparative test paints A to C containing a titania photocatalyst.

○ Antifouling performance of coated plate processed with photocatalyst-containing paint Apply test paint A containing titania photocatalyst to aluminum steel plate (5cm x 15cm) with bar coater (# 20), then air-dry overnight, test coated plate A was obtained. The same operation was performed for the test paints B to E and the comparative test paints A to C to obtain test application plates B to E and comparative test application plates A to C. Moreover, the board which apply | coated the original coating material which does not contain a titania type photocatalyst was similarly produced, and it was set as the blank.
In order to evaluate the antifouling performance of these coated plates, a methylene blue decomposition test was conducted. As a test method, the 2003 version (http://www.photocatalysis.com/index.html) liquid phase film adhesion method defined by the Photocatalyst Products Technical Council was used. However, a fluorescent lamp (Toshiba Life Tech / illuminance 2000 LUX) was used as the light source. The test results are shown in Table 5. When methylene blue was decolored, “decolorization” was displayed, and when methylene blue color remained, “decolorization pear” was displayed.

○ Evaluation of discoloration of coated plate processed with photocatalyst-containing paint The discoloration of the test coated plate and the comparative test coated plate after the antifouling test performed in Example 6 was visually examined. The results are shown in Table 6. The case where the paint on the test coating plate and the comparative test coating plate was colored yellow was indicated as “yellowing”, and the case where it was colored yellow-brown was indicated as “yellow browning”.

  From the results of Examples 6 and 7, it can be determined that the test paints A to E have a photocatalyst and are superior in resistance to discoloration due to ultraviolet irradiation compared to the comparative test paints A to C.

  The functional dispersion containing the titania-based photocatalyst of the present invention exhibits excellent photocatalytic performance under visible light, for example, a commercial fluorescent lamp. The functional dispersion of the present invention can be used as a functional processed product by using it in fibers, non-woven fabrics, filters, films, paints, paper, molded products and the like. By using this functional processed product, it is possible to decompose toxic gases such as antifouling, antibacterial, and aldehyde gas and attached substances in homes where ultraviolet irradiation is extremely low, and can be used for environmental purification. .

Is an IR spectrum of 1400-1700 cm ⁻¹ of powder A and powder A obtained by subjecting powder A to pyridine adsorption treatment (Pyr ⁺ ) Is an IR spectrum of 1400-1700 cm ⁻¹ of comparative powder B and comparative powder B subjected to pyridine adsorption treatment (Pyr ⁺ ).

Explanation of symbols

The horizontal axis in FIGS. 1 and 2 represents the wave number (cm ⁻¹ ) of infrared rays.
The vertical axis | shaft of FIG. 1 and FIG. 2 shows absorptivity.
The solid line in FIG. 1 and FIG. 2 shows the IR spectrum of the pyridine adsorbed treatment (Pyr ⁺ ).
The broken line in FIGS. 1 and 2 shows the IR spectrum of powder A or comparative powder B.

Claims (4)

  A functional dispersion containing a titania photocatalyst having a niobium content of 0.1 to 25% by mass.   2. The functional dispersion containing a titania-based photocatalyst according to claim 1, having an average particle diameter of 0.05 to 10 μm, an average pore diameter of 3 to 80 nm, and a crystallite diameter of 5 to 1000 nm.   The functional dispersion containing the titania-based photocatalyst according to claim 1 or 2, which has substantially no Lewis acid point.   The functional processed product which uses the functional dispersion liquid of each of Claims 1-3.

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