JP5137352B2 - Aqueous pollution control composition and painted product - Google Patents

Description

  The present invention relates to a water-based room temperature curable antifouling composition excellent in weatherability, water resistance and optical properties, and a coated product. The coated article of the present invention is hydrophilic and resistant to contamination for a long period of time, and is useful for outdoor display applications such as marking films, signboards, and displays.

Paints for outdoor display are contaminated by combustion products in exhaust gas of automobiles and the like, and accumulation of soot and dust floating in the atmosphere. In addition, suspended dust is carried by the rain in the rain, and when it flows down the surface of the outdoor display paint, contaminants adhere to the surface along the rainwater path, and when the surface dries, striped dirt is formed. Form. Such dirt on the outdoor display paint makes it difficult to see the display contents and disturbs the aesthetic landscape of the city. In addition, since many outdoor display paintings are at high places, the cleaning work is dangerous and takes time.
In view of the above problem, Patent Document 1 proposes an outdoor display panel having a surface layer portion containing photocatalyst particles and having a surface that is self-cleaned by rain (self-cleaning), and a cleaning method thereof. . By providing a surface layer containing a photocatalyst, the surface of the surface layer portion exhibits hydrophilicity in response to photoexcitation of the photocatalyst, so that deposits and / or contaminants are deposited when the surface of the outdoor display panel is exposed to rainfall. It can be washed away by raindrops. However, this method has a big problem that the base material deteriorates due to the organic substance decomposing action of the photocatalyst in the surface layer portion and the appearance of the outdoor display panel is deteriorated. Thus, for the purpose of preventing the deterioration due to the photocatalyst described above, a method of interposing a protective layer between the photocatalyst-containing surface layer portion has also been proposed, but this method has the disadvantage that workability is poor because the coating process increases. there were. In addition, a solvent-based silicone binder is used as a binder for sufficiently fixing the photocatalyst to the substrate. However, when the base material is a resin, there is a problem that when a silicone binder is used, optical characteristics are not sufficiently lowered and cannot be fixed due to problems of solvent resistance and heat resistance.
With respect to the above problem, Patent Document 2 proposes a method of emulsifying a silicone resin to make it water-based. However, a sufficient baking temperature on the base material requires a baking temperature of about 150 ° C., which is not suitable for a resin base material.
On the other hand, Patent Document 3, Patent Document 4, and Patent Document 5 each propose a method in which hydrophilic colloidal silica and an aqueous binder are used in combination as methods for imparting hydrophilicity to the coating film surface. However, both have problems that the stability of the coating liquid and the water resistance and transparency of the coating film are insufficient.

Japanese Patent Laid-Open No. 09-230810 JP-A-10-316937 Japanese Patent Laid-Open No. 11-001893 Japanese Patent Application Laid-Open No. 07-026165 JP 55-040717 A

  An object of the present invention is to provide a water-based antifouling composition capable of curing at room temperature, which can form a coated material that is excellent in weather resistance, water resistance, and optical properties and is resistant to staining for a long period of time with a small environmental load.

As a result of intensive studies aimed at solving the above problems, the present inventors have reached the present invention. That is, the present invention is as follows.
1) A composition for preventing water pollution comprising silica (A) and a water based binder (B1),
The water-based binder (B1) is a compound (b1) represented by the following formula (1) containing 3-methacryloxypropyltrimethoxysilane in the presence of water and an emulsifier, N-methylacrylamide, N-methylmethacrylamide, N-ethylacrylamide, N, N-dimethylacrylamide, N, N-dimethylmethacrylamide, N, N-diethylacrylamide, N-ethylmethacrylamide, N-methyl-N-ethylacrylamide, N-methyl-N-ethylmethacryl Amide, N-isopropylacrylamide, Nn-propylacrylamide, N-isopropylmethacrylamide, Nn-propylmethacrylamide, N-methyl-Nn-propylacrylamide, N-methyl-N-isopropylacrylamide, N- Vinyl pyrrolide , N- vinylcaprolactam, N- vinylacetamide, N- methacrylonitrile vinyl monomer having one or more secondary and / or tertiary amide group selected from acryloyl morpholine (b2) and copolymerizable therewith other An aqueous contamination-preventing composition comprising polymer emulsion particles (B2) having a number average particle size of 10 to 800 nm obtained by polymerizing a vinyl monomer (b2 ′).
MR _n W _xn (1)
(In the formula, M represents a metal atom. R represents a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, and an unsubstituted or carbon atom. It represents at least one hydrocarbon group selected from an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms substituted with a halogen atom, and W is carbon. At least one selected from an alkoxy group having 1 to 20 carbon atoms, a hydroxyl group, an acetoxy group having 1 to 20 carbon atoms, a halogen atom, a hydrogen atom, an oxime group having 1 to 20 carbon atoms, an enoxy group, an aminoxy group, and an amide group Represents a group, x represents the valence of the metal atom M, and n represents an integer of 1 to x.
2) the composition further above 1 aqueous antifouling composition, wherein the at least one metal oxide selected from metal oxides having photocatalytic activity.
3) The composition for preventing water pollution according to 1 or 2 above, wherein the polymer emulsion particles (B2) have a core / shell structure.
4) The composition for water pollution prevention according to any one of 1 to 3 above, wherein the number average particle diameter of the silica (A) is 1 to 400 nm.
5) A coated product comprising a contamination-preventing layer in which the composition for water-based contamination prevention according to any one of the above 1 to 4 is formed on one surface of a substrate.
6) The coated product as described in 5 above, wherein the surface of the coated product has a contact angle at 23 ° C. of 60 degrees or less.
7) The material according to 5 or 6 above, wherein the substrate is a resin selected from the group consisting of an acrylic resin, a methacrylic resin, a polyester resin, a polyolefin resin, a polystyrene resin, a polyamide resin, and a polyvinyl chloride resin. Paintings.
8) The painted product according to any one of 5 to 7 above, wherein the painted product is used for outdoor display.
9) A marking film comprising a contamination prevention layer formed from the aqueous contamination prevention composition according to any one of 1 to 4 above.
10) A signboard comprising a contamination prevention layer formed by the water-based contamination prevention composition according to any one of 1 to 4 above.
11) A sound insulation wall having a pollution control layer formed of the composition for preventing water pollution according to any one of 1 to 4 above.

  The water-based antifouling composition of the present invention is excellent in weather resistance, water resistance, and optical characteristics with a small environmental load, and can provide a coated product that is resistant to contamination over a long period of time.

Hereinafter, the present invention will be described in detail.
Examples of the metal oxide (A) used in the present invention include silicon dioxide (silica) such as colloidal silica, dry silica, and wet silica, aluminum oxide, antimony oxide, titanium oxide, indium oxide, tin oxide, and zirconium oxide. And lead oxide, iron oxide, calcium silicate, magnesium oxide, niobium oxide, cerium oxide, and complex oxides thereof. Among these, silicon dioxide (silica), aluminum oxide (alumina), antimony oxide, and complex oxides thereof having many surface hydroxyl groups are preferable.
Moreover, in this invention, when photocatalyst (a1) is selected as said metal oxide (A), since photocatalytic activity and / or hydrophilicity are expressed by light irradiation, it is preferable.
Here, the photocatalyst (a1) refers to a substance that causes an oxidation or reduction reaction by light irradiation. That is, when light (excitation light) with an energy larger than the energy gap between the conduction band and the valence band (ie, a short wavelength) is irradiated, excitation (photoexcitation) of electrons in the valence band occurs, resulting in conduction. It is a substance that can generate electrons and holes. At this time, various chemical reactions are performed using the reducing power of electrons generated in the conduction band and / or the oxidizing power of holes generated in the valence band. Can do.

The photocatalytic activity means that an oxidation or reduction reaction is caused by light irradiation. These photocatalytic activities can be determined, for example, by measuring the decomposability of organic substances such as pigments when the material surface is irradiated with light. A surface having photocatalytic activity exhibits excellent decomposition activity and contamination resistance of contaminating organic substances.
Furthermore, in the present invention, the hydrophilicity preferably means a case where the contact angle of water at 23 ° C. is 60 ° or less, and the surface having a hydrophilicity with a contact angle of water of 35 ° or less is particularly suitable for rain or the like. It is preferable because it exhibits stain resistance due to its self-purifying ability (self-cleaning). Further, from the standpoint of developing excellent stain resistance, the contact angle of water on the surface is preferably 10 ° or less, more preferably 5 ° or less.
Examples of the photocatalyst (a1) that can be usefully used as the metal oxide (A) of the present invention include semiconductor compounds having a band gap energy of 1.2 to 5.0 eV, preferably 1.5 to 4.1 eV. . If the band gap energy is smaller than 1.2 eV, the ability to cause oxidation and reduction reaction by light irradiation is weak, which is not preferable. If the band gap energy is greater than 5.0 eV, the energy of light necessary to generate holes and electrons increases, which is not preferable.

Examples of the photocatalyst (a1) include, for example, TiO ₂ , ZnO, SrTiO ₃ , BaTiO ₃ , BaTiO ₄ , BaTi ₄ O ₉ , K ₂ NbO ₃ , Nb ₂ O ₅ , Fe ₂ O ₃ , Ta ₂ O _5. , K ₃ Ta ₃ Si ₂ O ₃ , WO ₃ , SnO ₂ , Bi ₂ O ₃ , BiVO ₄ , NiO, Cu ₂ O, RuO ₂ , CeO ₂ etc., and further selected from Ti, Nb, Ta, V Layered oxides containing at least one element (for example, JP-A-62-074452, JP-A-02-172535, JP-A-07-024329, JP-A-08-089799, JP-A-08-089800 JP, 08-089804, JP 08-198061, JP 09-248465, JP 10-0996. 4 JP, see Publication No. Hei 10-244165) can be mentioned.
Among these photocatalysts (a1), TiO ₂ (titanium oxide) is preferable because it is harmless and has excellent chemical stability. Any of anatase, rutile, and brookite can be used as titanium oxide.
Moreover, as a photocatalyst (a1) used for the metal oxide (A) of the present invention, a visible light response capable of developing photocatalytic activity and / or hydrophilicity by irradiation with visible light (for example, a wavelength of about 400 to 800 nm). When the type photocatalyst is selected, the photocatalyst member treated with the photocatalyst composition of the present invention is preferable because the environmental purification effect and the antifouling effect in a place where ultraviolet rays such as indoors are not sufficiently irradiated are very large. The bandgap energy of these visible light responsive photocatalysts is preferably 1.2 to 3.1 eV, more preferably 1.5 to 2.9 eV, and still more preferably 1.5 to 2.8 eV.

Any visible light responsive photocatalyst can be used as long as it exhibits photocatalytic activity and / or hydrophilicity with visible light. For example, TaON, LaTiO ₂ N, CaNbO ₂ N, LaTaON ₂ , and CaTaO ₂ N can be used. Such as oxysulfide compounds such as Sm ₂ Ti ₂ S ₂ O ₇ (see, for example, JP 2002-233770 A), CaIn ₂ O ₄ , and SrIn _2. Oxides containing metal ions in the d10 electronic state such as O ₄ , ZnGa ₂ O ₄ , Na ₂ Sb ₂ O ₆ (see, for example, JP-A-2002-059008), titanium in the presence of nitrogen-containing compounds such as ammonia and urea. Oxide precursors (titanium oxysulfate, titanium chloride, alkoxy titanium, etc.) and high surface titanium oxide Nitrogen-doped titanium oxide obtained by firing (see, for example, JP-A-2002-029750, JP-A-2002-087818, JP-A-2002-154823, JP-A-2001-207082), sulfur such as thiourea By subjecting the titanium oxide precursor (titanium oxysulfate, titanium chloride, alkoxytitanium, etc.) to the sulfur-doped titanium oxide and titanium oxide obtained by firing in the presence of the compound by hydrogen plasma treatment or heat treatment under vacuum The obtained oxygen-deficient titanium oxide (see, for example, JP-A-2001-098219), further, photocatalyst particles are treated with a halogenated platinum compound (see, for example, JP-A-2002-239353), or treatment with tungsten alkoxide ( (See JP 2001-286755 A). Preferred examples include surface-treated photocatalysts.

Among the visible light responsive photocatalysts, oxynitride compounds and oxysulfide compounds have a large photocatalytic activity by visible light and can be used particularly preferably.
The oxynitride compound that can be particularly preferably used in the present invention is an oxynitride containing a transition metal, and preferably has a high photocatalytic activity, and the transition metal is preferably selected from the group consisting of Ta, Nb, Ti, Zr, and W. The oxynitride is characterized in that it further comprises at least one element selected from the group consisting of alkali, alkaline earth and group IIIB metals. The oxynitride further includes at least one metal element selected from the group consisting of Ca, Sr, Ba, Rb, La, and Nd.
Examples of oxynitride containing the transition _{metal, LaTiO 2 N, La v Ca} w TiO 2 N (v + w = 3), La v Ca w TaO 2 N (v + w = 3), LaTaON 2, CaTaO 2 N, General formula AMO _x N _y such as SrTaO ₂ N, BaTaO ₂ N, CaNbO ₂ N, CaWO ₂ N, SrWO ₂ N (A = alkali metal, alkaline earth metal, group IIIB metal; M = Ta, Nb, Ti, Zr, W; x + y = 3), TaON, NbON, WON, Li ₂ LaTa ₂ O ₆ N and the like. Among these, LaTiO ₂ N, La _v Ca _w TiO ₂ N (v + w = 3), La _v Ca _w TaO ₂ N (v + w = 3), and TaON are preferable because the photocatalytic activity in visible light is very large.

The oxysulfide compound that can be used particularly preferably in the present invention is an oxysulfide containing a transition metal, and has a high photocatalytic activity, and the transition metal is preferably selected from the group consisting of Ta, Nb, Ti, Zr, and W. Oxysulfide, characterized in that it is at least one, more preferably at least one element selected from the group consisting of alkali, alkaline earth and Group IIIB metals More preferably, the oxysulfide is characterized by further containing a rare earth element.
Examples of the oxysulfide containing the transition metal include Sm ₂ Ti ₂ S ₂ O ₅ , Nd ₂ Ti ₂ S ₂ O ₅ , La ₆ Ti ₂ S ₈ O ₅ , Pr ₂ Ti ₂ S ₂ O ₅ , and Sm _3. NbS ₃ O _{4 and the} like can be mentioned. Among these, Sm ₂ Ti ₂ S ₂ O ₅ and Nd ₂ Ti ₂ S ₂ O ₅ are very preferable because of their very high photocatalytic activity under visible light.
Further, the above-mentioned photocatalyst (a1) is preferably added or fixed with a metal such as Pt, Rh, Ru, Nb, Cu, Sn, Ni, Fe and / or an oxide thereof, silica, porous calcium phosphate, etc. (See, for example, JP-A-10-244166).

In the composition for preventing water pollution of the present invention, the number average particle size of the metal oxide (A) is preferably 1 to 400 nm in order to obtain a coated product excellent in weather resistance, water resistance, transparency and the like. Preferably, a metal oxide (A) of 1 to 100 nm, more preferably 5 to 50 nm is suitably selected.
As the form of the metal oxide (A) used in the present invention, any of powder, dispersion, and sol can be used. Here, the metal oxide (A) sol and the metal oxide (A) dispersion used in the present invention are each 0.01 to 80 mass of the metal oxide (A) in water and / or a hydrophilic organic solvent. %, Preferably 0.1 to 50% by mass, dispersed as primary particles and / or secondary particles.
Here, examples of the hydrophilic organic solvent used in the metal oxide (A) sol and the metal oxide (A) dispersion include ethylene glycol, butyl cellosolve, n-propanol, isopropanol, n-butanol, ethanol, Alcohols such as methanol, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, ethers such as tetrahydrofuran and dioxane, amides such as dimethylacetamide and dimethylformamide, dimethyl sulfoxide, nitrobenzene and the like, and two or more of these A mixture is mentioned.

The form of the metal oxide (A) used in the present invention is an important factor for the expression of functions such as the optical characteristics of the coated material to which the composition for preventing water pollution is applied. As the metal oxide (A) suitably used in the present invention, the number average particle diameter of a mixture of primary particles and secondary particles (which may be either primary particles or secondary particles) is 400 nm or less. A metal oxide (A) sol or a metal oxide (A) dispersion is desirable. In particular, when a metal oxide (A) sol or metal oxide (A) dispersion having a number average particle size of 100 nm or less is used, a coated product having excellent transparency is obtained from the composition for preventing water pollution of the present invention. It is very preferable because it can be used. More preferably, a metal oxide (A) sol or metal oxide (A) dispersion having a number average particle diameter of 80 nm or less and 3 nm or more, and more preferably 50 nm or less and 3 nm or more is suitably selected.
Examples of the aqueous binder (B1) used in the present invention include polyvinyl alcohol derivatives such as polyvinyl alcohol, cation-modified polyvinyl alcohol, and silanol-modified polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamides, starch and starch derivatives, carboxymethyl cellulose, hydroxyethyl cellulose, and the like. Cellulose derivatives, casein, gelatin, conventionally known poly (meth) acrylates, polyvinyl acetates, vinyl acetate-acrylic, ethylene vinyl acetates, silicones obtained by radical polymerization, anionic polymerization, cationic polymerization, etc. in aqueous media , Polybutadiene, styrene butadiene, NBR, polyvinyl chloride, chlorinated polypropylene, polyethylene, polystyrene, vinyl chloride Copolymers such as redene-based, polystyrene- (meth) acrylate-based, styrene-maleic anhydride-based, silicone-modified acrylic-based, fluorine-acrylic-based, acrylic-silicone, epoxy-acrylic-based modified copolymers, etc. Is mentioned.

Here, in the composition for preventing water pollution of the present invention, the metal oxide (A) may act as a curing agent by interacting with the binder (B1). This makes it possible to form a coated product that is excellent in weather resistance, water resistance, and optical properties and is not easily soiled from the composition for preventing water pollution of the present invention.
Here, examples of the interaction between the metal oxide (A) and the binder (B1) include a hydrogen bond between a hydroxyl group of silicon dioxide and a hydroxyl group, an amide group, or the like of the binder (B1). Therefore, the polymer emulsion particles (B2) having the secondary and / or tertiary amide groups and the hydrolyzable metal compound (b1) have not only hydrogen bonds but also hydroxyl groups and hydrolyzable metal compounds ( The above effect becomes remarkable due to condensation (chemical bond) with the polymerization product of b1), so that it can be preferably used.
The polymer emulsion particles (B2) used in the composition for preventing water pollution of the present invention are a vinyl monomer having a hydrolyzable metal compound (b1) and a secondary and / or tertiary amide group in the presence of water and an emulsifier. It can be obtained by polymerizing the body (b2).
At this time, the mass ratio [(b1) / (b2)] of the hydrolyzable metal compound (b1) and the vinyl monomer (b2) having a secondary and / or tertiary amide group is 5/95 to 95/5. , Preferably 10/90 to 90/10.
Further, the polymer emulsion particles (B2) obtained in this manner are a vinyl monomer (b2) having a hydroxyl group and a secondary and / or tertiary amide group of the polymerization product of the hydrolyzable metal compound (b1). ) And the polymerization product are combined in the particles by hydrogen bonding.

Examples of the hydrolyzable metal compound (b1) used for producing the polymer emulsion particles (B2) of the present invention include a compound represented by the following formula (1), a condensation product thereof, or a chelated product thereof. can do.
MR _n W _xn (1)
(In the formula, M represents a metal atom. R represents a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, and an unsubstituted or carbon atom. It represents at least one hydrocarbon group selected from an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms substituted with a halogen atom, and W is carbon. At least one selected from an alkoxy group having 1 to 20 carbon atoms, a hydroxyl group, an acetoxy group having 1 to 20 carbon atoms, a halogen atom, a hydrogen atom, an oxime group having 1 to 20 carbon atoms, an enoxy group, an aminoxy group, and an amide group Represents a group, x represents the valence of the metal atom M, and n represents an integer of 1 to x.
Examples of the hydrolyzable metal compound (b1) that can be preferably used in the present invention include silicon alkoxide, silane coupling agent, titanium alkoxide, zirconium from the viewpoints of reinforcing effect of coating film strength, ease of handling, material cost, and the like. Examples thereof include alkoxides and their condensation products, or chelating products thereof.
In this invention, a hydrolysable metal compound (b1) can be used individually or in mixture of 2 or more types or as a composite hydrolysable metal compound.

  Specific examples of the silicon alkoxide and silane coupling agent include tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-i-propoxysilane, and tetra-n-butoxysilane; Methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, i-propyltrimethoxysilane, i-propyltriethoxysilane, n- Butyltrimethoxysilane, n-butyltriethoxysilane, n-pentyltrimethoxysilane, n-hexyltrimethoxysilane, n-heptyltrimethoxysilane, n-octyltrimethoxysilane, vinyltrimethoxysilane Orchid, vinyltriethoxysilane, allyltrimethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 3, 3,3-trifluoropropyltrimethoxysilane, 3,3,3-trifluoropropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-hydroxyethyltrimethoxysilane, 2- Hydroxyethyltriethoxysilane, 2-hydroxypropyltrimethoxysilane, 2-hydroxypropyltriethoxysilane, 3-hydroxypropyltrimethoxysilane, 3-hydroxypropyltrimethoxysilane Toxisilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycid Xylpropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, 3- (Meth) acryloxypropyltriethoxysilane, 3- (meth) acryloyloxypropyltri-n-propoxysilane, 3- (meth) acryloyloxypropyltri-i-propoxysilane, 3-ureidopropi Trialkoxysilanes such as trimethoxysilane and 3-ureidopropyltriethoxysilane; dimethyldimethoxysilane, dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, di-n-propyldimethoxysilane, di-n-propyldi Ethoxysilane, di-i-propyldimethoxysilane, di-i-propyldiethoxysilane, di-n-butyldimethoxysilane, di-n-butyldiethoxysilane, di-n-pentyldimethoxysilane, di-n-pentyl Diethoxysilane, di-n-hexyldimethoxysilane, di-n-hexyldiethoxysilane, di-n-heptyldimethoxysilane, di-n-heptyldiethoxysilane, di-n-octyldimethoxysilane, di-n- Octyldiethoxysilane, di- Dialkoxysilanes such as n-cyclohexyldimethoxysilane, di-n-cyclohexyldiethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane, 3- (meth) acryloyloxypropylmethyldimethoxysilane; trimethylmethoxysilane, trimethylethoxysilane, etc. And monoalkoxysilanes. These silicon alkoxides and silane coupling agents can be used alone or in admixture of two or more.

When the silicon alkoxide or silane coupling agent is used as a condensation product, the condensation product preferably has a polystyrene equivalent weight average molecular weight of 200 to 5,000, more preferably 300 to 1,000.
Among the silicon alkoxides, silicon alkoxides having a phenyl group, for example, phenyltrimethoxysilane, phenyltriethoxysilane, diphenyldimethoxysilane, and the like are very preferable because of excellent polymerization stability in the presence of water and an emulsifier.
Specific examples of the titanium alkoxide include, for example, tetramethoxy titanium, tetraethoxy titanium, tetra-i-propoxy titanium, tetra-n-propoxy titanium, tetra-n-butoxy titanium, tetra-sec-butoxy titanium, tetra -Tert-butoxy titanium etc. are mentioned.
When the titanium alkoxide is used as a condensation product, the weight average molecular weight in terms of polystyrene of the condensation product is preferably 200 to 5,000, more preferably 300 to 1,000.

Specific examples of the zirconium alkoxide include tetramethoxy zirconium, tetraethoxy zirconium, tetra-i-propoxy zirconium, tetra-n-propoxy zirconium, tetra-n-butoxy zirconium, tetra-sec-butoxy zirconium, tetra-tert. -Butoxyzirconium etc. are mentioned.
When the zirconium alkoxide is used as a condensation product, the weight average molecular weight in terms of polystyrene of the condensation product is preferably 200 to 5,000, more preferably 300 to 1,000.
Further, as a preferable chelating agent for coordination with a free metal compound to form a chelate, alkanolamines such as diethanolamine and triethanolamine; glycols such as ethylene glycol, diethylene glycol and propylene glycol; acetylacetone; Examples thereof include ethyl acetoacetate having a molecular weight of 10,000 or less. By using these chelating agents, the polymerization rate of the hydrolyzable metal compound (b1) can be controlled, and this is very preferable in order to make the polymerization stability excellent in the presence of water and an emulsifier. In this case, the chelating agent is preferably used in a ratio of 0.1 mol to 2 mol per mol of the metal atom of the free metal compound that coordinates it.

  Among the hydrolyzable metal compounds (b1) that can be used in the present invention, 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, 3- (meth) acryloyl Oxypropylmethyldimethoxysilane, 3- (meth) acryloyloxypropyltri-n-propoxysilane, 3- (meth) acryloyloxypropyltri-i-propoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, Silane coupling agents having a double bond such as 2-trimethoxysilylethyl vinyl ether, and silane coupling agents having a thiol group such as 3-mercaptopropyltrimethoxysilane and 3-mercaptopropyltriethoxysilane are the above-mentioned 2 And / or copolymerized with a vinyl monomer (b1) having a tertiary amide group, or by a chain transfer reaction it is possible to generate a chemical bond. For this reason, a silane coupling agent having a double bond or a thiol group may be used alone or mixed with the above-mentioned silicon alkoxide, silane coupling agent, titanium alkoxide, zirconium alkoxide, and their condensation products, or their chelating products. When used in combination, the polymerization product of the hydrolyzable metal compound (b1) constituting the polymer emulsion particles (B2) of the present invention and a vinyl monomer having a secondary and / or tertiary amide group ( The polymerization product of b2) can be combined by chemical bonds in addition to hydrogen bonds. Since the water-based antifouling composition of the present invention containing such polymer emulsion particles (B2) can form a coated product having excellent weather resistance, water resistance and optical properties, it is very preferable.

Examples of the vinyl monomer (b2) having secondary and / or tertiary amide groups used for producing the polymer emulsion particles (B2) of the present invention include N-alkyl or N-alkylene substituted (meth) acrylamide. Specifically, for example, N-methylacrylamide, N-methylmethacrylamide, N-ethylacrylamide, N, N-dimethylacrylamide, N, N-dimethylmethacrylamide, N, N-diethylacrylamide N-ethylmethacrylamide, N-methyl-N-ethylacrylamide, N-methyl-N-ethylmethacrylamide, N-isopropylacrylamide, Nn-propylacrylamide, N-isopropylmethacrylamide, Nn-propylmethacrylamide Amido, N-methyl-Nn- Propylacrylamide, N-methyl-N-isopropylacrylamide, N-acryloylpyrrolidine, N-methacryloylpyrrolidine, N-acryloylpiperidine, N-methacryloylpiperidine, N-acryloylhexahydroazepine, N-acryloylmorpholine, N-methacryloylmorpholine, Examples thereof include N-vinylpyrrolidone, N-vinylcaprolactam, N, N′-methylenebisacrylamide, N, N′-methylenebismethacrylamide, N-vinylacetamide, diacetone acrylamide, diacetone methacrylamide and the like.
Among the vinyl monomers (b2) having the secondary and / or tertiary amide groups, N, N-diethylacrylamide is particularly excellent in polymerization stability in the presence of water and an emulsifier, and has been described above. Since it is possible to form a strong hydrogen bond with the hydroxyl group of the polymerization product of the hydrolyzable metal compound (b1) and the hydroxyl group of the metal oxide (A), it is very preferable.

In the present invention, when the polymerization of the vinyl monomer (b2) having the secondary and / or tertiary amide group is carried out together with another vinyl monomer (b2 ′) copolymerizable therewith, it is formed. It is possible to control the properties of the polymerized product (glass transition temperature, molecular weight, hydrogen bonding force, polarity, dispersion stability, weather resistance, compatibility of the hydrolyzable metal compound (b1) with the polymerized product, etc.) It is preferable. At this time, the vinyl monomer (b2) having a secondary and / or tertiary amide group needs to use at least 0.5% by mass of the total vinyl monomer, preferably 5% by mass. %, More preferably 20% by mass or more.
Examples of the vinyl monomer (b2 ′) include acrylic acid ester, methacrylic acid ester, aromatic vinyl compound, vinyl cyanide, carboxyl group-containing vinyl monomer, hydroxyl group-containing vinyl monomer, epoxy group Examples thereof include a monomer containing a functional group such as a vinyl monomer, a carbonyl group-containing vinyl monomer, and an anionic vinyl monomer.

Examples of the (meth) acrylic acid ester include (meth) acrylic acid alkyl ester having 1 to 50 carbon atoms in the alkyl moiety and (poly) oxyethylene di (meth) having 1 to 100 ethylene oxide groups. An acrylate etc. are mentioned. Specific examples of (meth) acrylic acid esters include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and methyl (meth) acrylate. Examples include cyclohexyl, cyclohexyl (meth) acrylate, lauryl (meth) acrylate, dodecyl (meth) acrylate, and the like. Specific examples of (poly) oxyethylene di (meth) acrylate include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, diethylene glycol methoxy (meth) acrylate, tetraethylene glycol di (meth) acrylate Etc.
Here, (meth) acryl is a simple description of methacryl or acrylic.
The amount of the (meth) acrylic acid ester used is preferably 0 to 99.9% by mass, more preferably 5 to 80% by mass in the total vinyl monomer as one or a mixture of two or more.

Examples of the carboxyl group-containing vinyl monomer include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, maleic anhydride, or half of a dibasic acid such as itaconic acid, maleic acid, and fumaric acid. Esters and the like. By using a carboxylic acid group-containing vinyl monomer, a carboxyl group can be introduced into the polymer emulsion particles (B), improving the stability as an emulsion, and having a resistance to dispersion and destruction from the outside. It is possible to have it. At this time, a part or all of the introduced carboxyl group can be neutralized with an amine such as ammonia, triethylamine or dimethylethanolamine, or a base such as NaOH or KOH.
The use amount of the carboxyl group-containing vinyl monomer is preferably 0 to 50% by mass, more preferably 0.1 to 10% by mass, more preferably 1% or a mixture of two or more in all vinyl monomers. Is 0.1-5 mass%. If it exceeds 30% by mass, the water resistance of the coating film may be lowered, which is not preferable.

  Examples of the hydroxyl group-containing vinyl monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 3 -Hydroxyalkyl esters of (meth) acrylic acid such as hydroxybutyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate, di-2-hydroxyethyl fumarate, mono-2-hydroxyethyl monobutyl fumarate, allyl alcohol And (poly) oxyethylene mono (meth) acrylate having 1 to 100 ethylene oxide groups, (poly) oxypropylene mono (meth) acrylate having 1 to 100 propylene oxide groups, FM, F Monomer "[manufactured by Daicel Chemical Co., trade name of caprolactone addition monomer] and other alpha, and the like hydroxyalkyl esters of β- ethylenically unsaturated carboxylic acid. Specific examples of the (poly) oxyethylene (meth) acrylate include ethylene glycol (meth) acrylate, ethylene glycol methoxy (meth) acrylate, diethylene glycol (meth) acrylate, diethylene glycol methoxy (meth) acrylate, (meth ) Tetraethylene glycol acrylate, tetraethylene glycol methoxy (meth) acrylate, and the like. Specific examples of (poly) oxypropylene (meth) acrylate include propylene glycol (meth) acrylate, propylene glycol methoxy (meth) acrylate, dipropylene glycol (meth) acrylate, dimethoxy meth (meth) acrylate. Examples include propylene glycol, tetrapropylene glycol (meth) acrylate, and tetrapropylene glycol methoxy (meth) acrylate. By using a hydroxyl group-containing vinyl monomer, it becomes possible to control the hydrogen bonding force of the polymerization product with the vinyl monomer (b2) having a secondary and / or tertiary amide group, and a polymer. It becomes possible to improve the water dispersion stability of the emulsion particles (B2).

The use amount of the hydroxyl group-containing vinyl monomer described above is preferably 0 to 80% by mass, more preferably 0.1 to 50% by mass, and more preferably 0.1 to 50% by mass in the total vinyl monomer as one or a mixture of two or more. Preferably it is 0.1-10 mass%.
Examples of the glycidyl group-containing vinyl monomer include glycidyl (meth) acrylate, allyl glycidyl ether, and allyl dimethyl glycidyl ether.
Examples of the carbonyl group-containing vinyl monomer include acrolein, diacetone acrylamide, diacetone methacrylamide, formyl styrene, vinyl methyl ketone, vinyl ethyl ketone, vinyl isobutyl ketone, acryloxyalkylpropanals, methacryloxyalkylpropanal. , Diacetone acrylate, diacetone methacrylate, acetonyl acrylate, 2-hydroxypropyl acrylate acetyl acetate, butanediol acrylate acetyl acetate, acetone dicarboxylic acid, dihydroxyacetone, monohydroxyacetone, and dihydroxybenzaldehyde. Vinyl monomers containing carbonyl groups of acids and esters are excluded.

When a glycidyl group-containing vinyl monomer or a carbonyl group-containing vinyl monomer is used, the polymer emulsion particles (B2) are reactive and crosslinked by hydrazine derivatives, carboxylic acid derivatives, isocyanate derivatives, etc. It is possible to form an organic / inorganic composite having excellent properties. The amount of the glycidyl group-containing vinyl monomer or the carbonyl group-containing vinyl monomer used is preferably 0 to 50% by mass in the total vinyl monomers.
Specific examples of the vinyl monomer (b2 ′) other than the above include, for example, (meth) acrylamide, olefins such as ethylene, propylene, and isobutylene, dienes such as butadiene, vinyl chloride, vinylidene chloride, Haloolefins such as tetrafluoroethylene and chlorotrifluoroethylene, vinyl acetate, vinyl propionate, vinyl n-butyrate, vinyl benzoate, vinyl pt-butylbenzoate, vinyl pivalate, vinyl 2-ethylhexanoate, Carboxylic acid vinyl esters such as vinyl versatate and vinyl laurate, isopropenyl acetate, isopropenyl carboxylic acid esters such as isopropenyl propionate, vinyl ethers such as ethyl vinyl ether, isobutyl vinyl ether, cyclohexyl vinyl ether, Aromatic vinyl compounds such as styrene and vinyltoluene, allyl esters such as allyl acetate and allyl benzoate, allyl ethers such as allyl ethyl ether and allyl phenyl ether, and 4- (meth) acryloyloxy-2,2,6 , 6, -tetramethylpiperidine, 4- (meth) acryloyloxy-1,2,2,6,6, -pentamethylpiperidine, perfluoromethyl (meth) acrylate, perfluoropropyl (meth) acrylate, perfluoropro Examples thereof include pyromethyl (meth) acrylate, vinyl pyrrolidone, trimethylolpropane tri (meth) acrylate, allyl (meth) acrylate, and the like and combinations thereof.

In the present invention, a vinyl monomer (b2) having a secondary and / or tertiary amide group (the vinyl monomer (b2 ′) copolymerizable therewith may be used if necessary). A chain transfer agent may be used for the purpose of controlling the molecular weight of the polymerization product.
Examples of such chain transfer agents include alkyl mercaptans such as n-octyl mercaptan, n-dodecyl mercaptan, t-dodecyl mercaptan; aromatic mercaptans such as benzyl mercaptan and dodecyl benzyl mercaptan; thiocarboxylic acids such as thiomalic acid, or Examples thereof include salts thereof, alkyl esters thereof, polythiols, diisopropylxanthogen disulfide, di (methylenetrimethylolpropane) xanthogen disulfide and thioglycol, and allyl compounds such as a dimer of α-methylstyrene. .
The amount of these chain transfer agents used is preferably 0.001 to 30% by mass, more preferably 0.05 to 10% by mass, based on the total vinyl monomer.

In the present invention, examples of the emulsifier that can be used for the synthesis of the polymer emulsion particles (B2) include alkylbenzene sulfonic acid, alkyl sulfonic acid, alkyl sulfosuccinic acid, polyoxyethylene alkyl sulfuric acid, polyoxyethylene alkyl aryl sulfuric acid, Acidic emulsifiers such as oxyethylene distyryl phenyl ether sulfonic acid, alkali metal (Li, Na, K, etc.) salts of acidic emulsifiers, ammonium salts of acidic emulsifiers, anionic surfactants such as fatty acid soaps, for example alkyltrimethylammonium bromide , Quaternary ammonium salts such as alkylpyridinium bromide and imidazolinium laurate, pyridinium salts, imidazolinium salt type cationic surfactants, polyoxyethylene alkylaryl ethers, polyoxy Sorbitan fatty acid esters, polyoxyethylene polyoxypropylene block copolymers can be exemplified reactive emulsifier or the like having a nonionic surface active agent and a radical polymerizable double bond polyoxyethylene distyryl phenyl ether.
Among these emulsifiers, when a reactive emulsifier having a radical polymerizable double bond is selected, the water dispersion stability of the polymer emulsion particles (B2) of the present invention becomes very good, and the polymer emulsion The composition for preventing water-based contamination of the present invention containing the particles (B2) is very preferable because a coated product excellent in weather resistance, water resistance and optical properties can be formed.

Examples of the reactive emulsifier having a radical polymerizable double bond include a vinyl monomer having a sulfonic acid group or a sulfonate group, a vinyl monomer having a sulfate ester group, an alkali metal salt thereof, an ammonium salt, Examples include vinyl monomers having a nonionic group such as oxyethylene, and vinyl monomers having a quaternary ammonium salt.
As a specific example of the reactive emulsifier, a salt of a vinyl monomer having a sulfonic acid group or a sulfonate group will be described as an example. Ammonium salt or sodium salt of a sulfonic acid group having a radical polymerizable double bond. Or an alkyl group having 1 to 20 carbon atoms, an alkyl ether group having 2 to 4 carbon atoms, a polyalkyl ether group having 2 to 4 carbon atoms, a 6 or 10 carbon atom, partially substituted with a group that is a potassium salt It is a compound having a substituent selected from the group consisting of an aryl group and a succinic acid group, or a vinyl sulfonate compound having a vinyl group to which an ammonium salt, sodium salt or potassium salt of a sulfonic acid group is bonded. . The vinyl monomer having a sulfate ester group has a radically polymerizable double bond and is partially substituted by a group that is an ammonium salt, sodium salt or potassium salt of a sulfate ester group, having 1 to 1 carbon atoms. It is a compound having a substituent selected from the group consisting of 20 alkyl groups, alkyl ether groups having 2 to 4 carbon atoms, polyalkyl ether groups having 2 to 4 carbon atoms, and aryl groups having 6 or 10 carbon atoms.

Specific examples of the compound having a succinic acid group partially substituted with a group which is an ammonium salt, sodium salt or potassium salt of the sulfonic acid group include allyl sulfosuccinate. Specific examples thereof include, for example, Eleminol JS-2 (trade name) (manufactured by Sanyo Kasei Co., Ltd.), Latemuru S-120, S-180A or S-180 (trade name) (manufactured by Kao Corporation), and the like. Can be mentioned.
Further, a compound having an alkyl ether group having 2 to 4 carbon atoms or a polyalkyl ether group having 2 to 4 carbon atoms, which is partially substituted by a group which is an ammonium salt, sodium salt or potassium salt of the sulfonic acid group. As specific examples, for example, Aqualon HS-10 or KH-1025 (trade name) (Daiichi Kogyo Seiyaku Co., Ltd.), Adekaria soap SE-1025N or SR-1025 (trade name) (Asahi Denka Kogyo Co., Ltd.) And the like.
Other specific examples of the compound having an aryl group partially substituted with a sulfonate group include ammonium salt, sodium salt and potassium salt of p-styrenesulfonic acid.
Examples of the vinyl sulfonate compound having a vinyl group to which a group of ammonium salt, sodium salt or potassium salt of the sulfonic acid group is bonded include, for example, alkyl sulfonic acid (meth) acrylate such as 2-sulfoethyl acrylate, and methylpropane sulfonic acid. Examples thereof include ammonium salts such as (meth) acrylamide and allylsulfonic acid, sodium salts, and potassium salts.

Examples of the compound having an alkyl ether group having 2 to 4 carbon atoms or a polyalkyl ether group having 2 to 4 carbon atoms partially substituted with the ammonium salt, sodium salt or potassium salt of the sulfate ester group include, for example, Examples include compounds having an alkyl ether group partially substituted with a sulfonate group.
In addition, specific examples of vinyl monomers having a nonionic group include α- [1-[(allyloxy) methyl] -2- (nonylphenoxy) ethyl] -ω-hydroxypolyoxyethylene (trade name: ADEKA rear soap). NE-20, NE-30, NE-40, etc., manufactured by Asahi Denka Kogyo Co., Ltd.), polyoxyethylene alkylpropenyl phenyl ether (trade names: Aqualon RN-10, RN-20, RN-30, RN-50, etc.) , Manufactured by Daiichi Pharmaceutical Co., Ltd.).
As the usage-amount of the said emulsifier, the inside of the range used as 10 mass parts or less is suitable with respect to 100 mass parts of polymer emulsion particles (B2), Especially, within the range used as 0.001-5 mass parts. preferable.

In addition to the above emulsifiers, a dispersion stabilizer may be used for the purpose of improving the water dispersion stability of the polymer emulsion particles (B2) of the present invention. Examples of the dispersion stabilizer include various water-soluble oligomers selected from the group consisting of polycarboxylic acids and sulfonates, polyvinyl alcohol, hydroxyethyl cellulose, starch, maleated polybutadiene, maleated alkyd resin, polyacrylic acid (salt ), Synthetic or natural water-soluble or water-dispersible water-soluble polymer substances such as polyacrylamide, water-soluble or water-dispersible acrylic resin, etc., and one or a mixture of two or more of these are used. be able to.
When these dispersion stabilizers are used, the amount used is suitably within a range of 10 parts by mass or less with respect to 100 parts by mass of the polymer emulsion particles (B2). The range of 5 parts by mass is preferable.
In the present invention, the polymerization of the hydrolyzable metal compound (b1) and the vinyl monomer (b2) having a secondary and / or tertiary amide group is preferably carried out in the presence of a polymerization catalyst.

Here, as a polymerization catalyst for the hydrolyzable metal compound (b1), hydrogen halides such as hydrochloric acid and hydrofluoric acid, carboxylic acids such as acetic acid, trichloroacetic acid, trifluoroacetic acid and lactic acid, sulfuric acid, and p-toluenesulfonic acid Sulfonic acids such as alkylbenzene sulfonic acid, alkyl sulfonic acid, alkyl sulfosuccinic acid, polyoxyethylene alkyl sulfuric acid, polyoxyethylene alkyl aryl sulfuric acid, polyoxyethylene distyryl phenyl ether sulfonic acid, etc., acidic or weakly acidic emulsifier Acidic compounds such as inorganic salts, phthalic acid, phosphoric acid, nitric acid; sodium hydroxide, potassium hydroxide, sodium methylate, sodium acetate, tetramethylammonium chloride, tetramethylammonium hydroxide, tributylamine, diazabicyclo Basic compounds such as decene, ethylenediamine, diethylenetriamine, ethanolamine, γ-aminopropyltrimethoxysilane, γ- (2-aminoethyl) -aminopropyltrimethoxysilane; tin such as dibutyltin octylate, dibutyltin dilaurate A compound etc. can be mentioned.
Among these, as a polymerization catalyst for the hydrolyzable metal compound (b1), acidic emulsifiers having an action as an emulsifier as well as a polymerization catalyst, particularly alkylbenzenesulfonic acid (dodecylbenzenesulfonic acid having 5 to 30 carbon atoms). Etc.) is highly preferred.

On the other hand, the polymerization catalyst for the vinyl monomer (b1) having a secondary and / or tertiary amide group is a radical polymerization catalyst that causes radical polymerization by heat or a reducing substance to cause addition polymerization of the vinyl monomer. And water-soluble or oil-soluble persulfates, peroxides, azobis compounds and the like are used. Examples include potassium persulfate, sodium persulfate, ammonium persulfate, hydrogen peroxide, t-butyl hydroperoxide, t-butyl peroxybenzoate, 2,2-azobisisobutyronitrile, 2,2-azobis. There are (2-diaminopropane) hydrochloride, 2,2-azobis (2,4-dimethylvaleronitrile), and the amount thereof is 0.001 to 5 parts by mass with respect to 100 parts by mass of all vinyl monomers. Is preferable. When acceleration of the polymerization rate and polymerization at a low temperature of 70 ° C. or lower are desired, it is advantageous to use a reducing agent such as sodium bisulfite, ferrous chloride, ascorbate, or longalite in combination with the radical polymerization catalyst. is there.
As described above, the polymer emulsion particles (B2) used in the composition for preventing water pollution of the present invention are composed of a hydrolyzable metal compound (b1) and secondary and / or tertiary amide groups in the presence of water and an emulsifier. The vinyl monomer (b2) having the above-mentioned [other vinyl monomer (b2 ′) copolymerizable with this may be used if necessary] is preferably obtained by polymerization in the presence of a polymerization catalyst. be able to.

Here, the polymerization of the hydrolyzable metal compound (b1) and the vinyl monomer (b2) having a secondary and / or tertiary amide group can be carried out separately, but by carrying out at the same time. This is preferable because microscopic organic / inorganic complexation by hydrogen bonding or the like can be achieved in the particles.
In the present invention, it is important that the number average particle diameter of the polymer emulsion particles (B2) is 10 to 800 nm. By adjusting to such a particle diameter range and combining with a metal oxide (A) having a number average particle diameter of 1 to 400 nm to form a micro organic / inorganic composite due to hydrogen bonds or the like in the particles, It becomes possible to form a coated product that has excellent weather resistance, water resistance, optical properties, and has a characteristic of being difficult to get dirty for a long time. The number average particle diameter of the polymer emulsion particles (B2) is also preferably 10 nm to 800 nm, more preferably 50 to 300 nm.
As a method for obtaining polymer emulsion particles (B2) having such a particle size, the hydrolyzable metal compound (b1) and secondary and / or 3 in the presence of a sufficient amount of water for the emulsifier to form micelles. So-called emulsion polymerization in which the vinyl monomer (b2) having a secondary amide group is polymerized is the most suitable method.

Examples of the emulsion polymerization method include a hydrolyzable metal compound (b1) and a vinyl monomer (b2) having a secondary and / or tertiary amide group [other vinyl copolymerizable with this if necessary. The monomer (b2 ′)] is dropped into the reaction vessel as it is or in an emulsified state at once, in a divided manner or continuously, and in the presence of the polymerization catalyst, preferably the pressure is from atmospheric pressure. The polymerization may be carried out at a temperature of 10 MPa and a reaction temperature of about 30 to 150 ° C. if necessary. In some cases, the polymerization may be carried out even at a higher pressure or lower temperature. The ratio of the total amount of the hydrolyzable metal compound (b1) and all vinyl monomers to water is set so that the final solid content is in the range of 0.1 to 70% by mass, preferably 1 to 55% by mass. Is preferred. In order to grow or control the particle diameter in emulsion polymerization, a seed polymerization method in which emulsion particles are preliminarily present in the aqueous phase for polymerization may be used. The polymerization reaction may be allowed to proceed in the range of pH in the system of preferably 1.0 to 10.0, more preferably 1.0 to 6.0. The pH can be adjusted by using a pH buffer such as disodium phosphate, borax, sodium hydrogen carbonate, or ammonia.
Further, as a method for obtaining the polymer emulsion particles (B2) of the present invention, the hydrolyzable metal compound (b1) and the secondary compound in the presence of water and an emulsifier necessary for polymerizing the hydrolyzable metal compound (b1). And / or a method of adding water until the polymerization product becomes an emulsion after polymerizing the vinyl monomer (b2) having a tertiary amide group, if necessary, in the presence of a solvent. Compared with the method, it is difficult to control the particle diameter of the resulting polymer emulsion particles (B2).

In the present invention, when the polymer emulsion particles (B2) have a core / shell structure, the composition for preventing water-based contamination containing the polymer emulsion particles (B2) has mechanical properties (such as a balance between strength and flexibility). It is possible to form a coated product excellent in the above).
Multi-stage emulsion polymerization is very useful as a method for producing the core / shell structured polymer emulsion particles (B2).
Here, the multi-stage emulsion polymerization means two or more different hydrolyzable metal compounds (b1) and vinyl monomers (b2) having secondary and / or tertiary amide groups [if necessary, this Other vinyl monomers (b2 ′)] that can be copolymerized with the polymer, and polymerizing them in separate stages.
The synthesis of the polymer emulsion particles (B2) by the multistage emulsion polymerization of the present invention will be described below by taking the synthesis of the polymer emulsion particles (B2) by the two-stage emulsion polymerization as the simplest and most useful among the multistage emulsion polymerizations. To do.

In the present invention, as the synthesis of the polymer emulsion particles (B2) by two-stage emulsion polymerization, for example, the vinyl monomer (C) and / or the hydrolyzable metal compound (b1) is polymerized in the presence of water and an emulsifier. A method of polymerizing the hydrolyzable metal compound (b1) and the vinyl monomer (b2) having a secondary and / or tertiary amide group in the presence of the obtained seed particles can be exemplified.
Here, the vinyl monomer (C) means a vinyl monomer (b2) having a secondary and / or tertiary amide group and / or the other vinyl monomer (b2 ′) described above.
In the synthesis of the polymer emulsion particles (B) by the above-mentioned two-stage emulsion polymerization, the first series [the vinyl monomer (C) and / or the hydrolyzable metal compound (b1)] is supplied and emulsion polymerization is performed. And the second series {hydrolyzable metal compound (b1) and vinyl monomer (b2) having secondary and / or tertiary amide group [copolymerized with this if necessary] The other possible vinyl monomer (b2 ′)]} is supplied and obtained by a two-stage polymerization process comprising a second-stage polymerization in which emulsion polymerization is carried out in an aqueous medium. At this time, the mass ratio of the solid content mass (M1) in the first series to the solid content mass (M2) in the second series is preferably (M1) / (M2) = 9/1 to 1/9, More preferably, it is 8/2 to 2/8, and further preferably 7/3 to 3/7.

In the present invention, the preferred core / shell structure polymer is characterized in that the particle size of the seed particles obtained by the first stage polymerization is not greatly changed in the particle size distribution (volume average particle size / number average particle size). (Preferably in a monodispersed state) can be increased by the second stage polymerization (increase in particle diameter).
The core / shell structure can be confirmed by, for example, morphological observation with a transmission electron microscope, analysis by viscoelasticity measurement, or the like.
In the above-described polymer emulsion particles (B2) having a core / shell structure, the glass transition temperature (Tg) of the core phase is 0 ° C. or lower, that is, the glass transition temperature of the seed particles is 0 ° C. or lower. It is possible to form a coated product that is excellent in flexibility at room temperature and hardly causes cracking or the like from the composition for preventing water-based contamination contained therein.
As a method for producing polymer emulsion particles (B2) having a glass transition temperature (Tg) of the core phase of 0 ° C. or less and excellent weather resistance, hydrolyzable silicon compound (b1) and / or cyclic in the presence of water and an emulsifier A method of polymerizing a hydrolyzable metal compound (b1) and a vinyl monomer (b2) having a secondary and / or tertiary amide group in the presence of seed particles obtained by polymerizing a siloxane oligomer can be suitably exemplified. .

Here, as a cyclic siloxane oligomer, the compound represented by following formula (2) can be illustrated.
(R ′ ₂ SiO) _m (2)
(In the formula, R ′ is a hydrogen atom, a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, and an unsubstituted or substituted carbon group having 1 to 30 carbon atoms. It represents at least one selected from an alkyl group having 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms substituted with a halogen atom, where m is an integer and 2 ≦ m ≦ 20. .)
Among the cyclic siloxane oligomers, cyclic dimethylsiloxane oligomers such as octamethylcyclotetrasiloxane are preferable from the viewpoint of reactivity.
As the cyclic siloxane oligomer, those exemplified as the polymerization catalyst for the hydrolyzable metal compound (b1) can be suitably used as the polymerization catalyst.

In the present invention, when carrying out multi-stage emulsion polymerization of three or more stages, the number of series to be polymerized may be increased with reference to the synthesis example of the polymer emulsion particles (B2) by the two-stage polymerization described above.
The composition for preventing water-based contamination of the present invention comprises the above-described metal oxide (A) having a number average particle size of 1 to 400 nm, hydrolyzable metal compound (b1), secondary and / or in the presence of water and an emulsifier. Alternatively, it is characterized by comprising polymer emulsion particles (B2) having a number average particle diameter of 10 to 800 nm obtained by polymerizing a vinyl monomer (b2) having a tertiary amide group.
Here, the mass ratio (A) / (B2) of the metal oxide (A) and the polymer emulsion particles (B2) is 1/99 to 99/1, preferably 5/95 to 90/10, more preferably. 10/90 to 80/20. The solid content in the case of using the composition for preventing water-based contamination as a coating agent is preferably 0.01 to 60% by mass, more preferably 1 to 40% by mass. The viscosity at that time is preferably 0.1 to 100,000 mPa · s, preferably 1 to 10000 mPa · s at 20 ° C.
Moreover, alcohols can also be added to the composition for preventing water pollution of the present invention for the purpose of controlling the interaction such as hydrogen bonding between the metal oxide (A) and the polymer emulsion particles (B2). Addition of alcohol greatly improves storage stability and the like.

Examples of the alcohols include methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, modified ethanol, glycerin, monoalkyl monoglyceryl ether having 3 to 8 carbon atoms in the alkyl chain, and propylene glycol monomethyl. Ether, diethylene glycol monobutyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monobutyl ether or di to tetraethylene glycol monophenyl ether are preferred. Of these, ethanol is most preferable from the environmental viewpoint.
As a base material of this invention, organic base materials, such as a synthetic resin and a natural resin, inorganic base materials, such as a metal, ceramics, glass, stone, cement, concrete, those combinations, etc. can be mentioned, for example.
As the synthetic resin, a thermoplastic resin and a curable resin (thermosetting resin, photocurable resin, moisture curable resin, etc.) can be used. For example, silicone resin, acrylic resin, methacrylic resin, fluororesin, Alkyd resin, amino alkyd resin, vinyl resin, polyester resin, styrene-butadiene resin, polyolefin resin, polystyrene resin, polyketone resin, polyamide resin, polycarbonate resin, polyacetal resin, polyether ether ketone resin, polyphenylene oxide resin, polysulfone resin, Examples thereof include polyphenylene sulfone resin, polyether resin, polyvinyl chloride resin, polyvinylidene chloride resin, urea resin, phenol resin, melamine resin, epoxy resin, urethane resin, and silicone-acrylic resin.
Examples of the natural resin include cellulose resins, isoprene resins such as natural rubber, and protein resins such as casein.
In the present invention, the surface of the resin plate may be subjected to surface treatments such as corona discharge treatment, flame treatment, and plasma treatment, but these surface treatments are not essential.
The type and film thickness of the substrate used in the present invention can be properly used depending on the application. For example, in the case of marking film use, a film made of polyvinyl chloride resin having a film thickness of 20 to 200 μm is preferable from the viewpoint of moldability and economy, and in the case of signboards such as surface light emitting boards and sound insulation walls, the acrylic resin plate is strong and weather resistant. It is preferably used from the viewpoints of properties and transparency.

In addition, the composition for preventing water-based contamination of the present invention includes components that are usually added and blended in paints and molding resins, for example, thickeners, leveling agents, thixotropic agents, depending on the application and method of use. , Antifoaming agent, Freezing stabilizer, Matting agent, Crosslinking reaction catalyst, Pigment, Curing catalyst, Crosslinking agent, Filler, Anti-skinning agent, Dispersant, Wetting agent, Light stabilizer, Antioxidant, UV absorber , Rheology control agent, defoaming agent, film forming aid, rust preventive agent, dye, plasticizer, lubricant, reducing agent, antiseptic, antifungal agent, deodorant, anti-yellowing agent, antistatic agent or A charge adjusting agent or the like can be selected and combined in accordance with each purpose.
The coated article formed with the antifouling layer containing the water-based antifouling composition of the present invention is excellent in weather resistance, water resistance and optical properties, and also has excellent antifouling properties when the water contact angle at 23 ° C. is 60 ° or less. In particular, when a metal oxide (photocatalyst) having photocatalytic activity is used as the metal oxide (A), an excellent pollutant organic substance can be obtained by irradiating light with energy higher than the band gap energy of the photocatalyst contained therein. By decomposing, the water contact angle at 23 ° C. can be maintained over a long period of time.
Here, as a light source of light having energy higher than the band gap energy of the photocatalyst, light such as sunlight, indoor lighting, and light obtained in a general residential environment, light such as black light, xenon lamp, mercury lamp, LED, etc. Is available.

In the present invention, it is preferable that the coated product is formed in a state where the metal oxide (A) such as silicon dioxide effectively works as a curing agent for the polymer emulsion particles (B2). As an example of such a preferable coating film, a metal oxide (A) such as silicon dioxide forms a continuous layer between the particles of the polymer emulsion particles (B2) while interacting with the polymer emulsion particles (B2). Can be mentioned. By forming such a form, it is possible to obtain a coated product particularly excellent in weather resistance, optical characteristics, and the like.
In order to obtain a coated product having a coating film having the above-described form, the mass ratio (A) / (B2) of the metal oxide (A) and the polymer emulsion particles (B2) in the composition for preventing water pollution is set. It is most effective to set the optimum range. The optimum range of the mass ratio (A) / (B2) is, for example, the transparency of a coating film in which the mass ratio (A) / (B2) is changed, and the mass ratio (A ) / (B2). Here, when the metal oxide (A) and the polymer emulsion particles (B2) to be used are the same, the range of the above optimum mass ratio (A) / (B2) is the metal oxide (A ) And the ratio (rA2) / (rB2) of the particle size (rB2) of the polymer emulsion particles (B2).
For example, when (rA) / (rB2) is 0.05 to 0.2, the range of the mass ratio (A) / (B2) is preferably 20/80 to 80/20, more preferably 30 / It is 70-70 / 30, Most preferably, it is 40 / 60-60 / 40.
Moreover, when the silicon oxide (A1) and the metal oxide (A2) having photocatalytic activity are used in combination as the metal oxide (A), the self-cleaning property of the coating film can be maintained for a long period of time. Therefore, the range of the mass ratio (A1) / (A2) between the silicon dioxide (A1) and the metal oxide (A2) having photocatalytic activity is preferably 50/50 to 99/1, more preferably 80/20. It is -97/3, Most preferably, it is 85 / 15-95 / 5.
On the other hand, if the mass ratio (A2) / (B2) of the metal oxide (A2) having photocatalytic activity to the polymer emulsion particles (B2) is too high, light irradiation of the organic / inorganic composite formed on the substrate is performed. Deterioration due to is remarkable, which is not preferable. Therefore, the range of the mass ratio (A2) / (B2) is preferably 1/99 to 50/50, more preferably 3/97 to 20/80, and most preferably 5/95 to 15/85. It is.

In the present invention, the polymer emulsion particles (B2) have a core / shell structure, the shell phase interacts with the metal oxide (A) to form a continuous layer, and the particulate core phase is the continuous layer. The form present therein is most preferred. The coating film having such a form has not only excellent weather resistance, water resistance and optical properties, but also excellent mechanical properties (such as a balance between strength and flexibility).
The coated product of the present invention, for example, after applying the composition for preventing water-based contamination to a substrate and drying at a low temperature of 20 ° C. to 80 ° C., preferably 20 ° C. to 500 ° C., more preferably 40 ° C. to It can be obtained by performing a heat treatment at 250 ° C., ultraviolet irradiation, or the like to form a coating film of a contamination prevention layer on the substrate. Examples of the coating method include spray spraying, flow coating, roll coating, brush coating, dip coating, spin coating, screen printing, casting, gravure printing, flexographic printing, and the like.

When forming the composition for water pollution prevention of this invention as a coating film on a base material, it is preferable that the thickness of this coating film is 0.05-100 micrometers, Preferably it is 0.1-10 micrometers. The thickness is preferably 100 μm or less from the viewpoint of transparency, and in order to exhibit functions such as antifouling properties and photocatalytic activity, the thickness is preferably 0.05 μm or more.
In this specification, the expression “coating film” is used, but it is not necessarily a continuous film, and may be a discontinuous film, an island-shaped dispersion film, or the like.
The method for producing a coated product of the present invention is not limited to the case where the composition for preventing water-based contamination of the present invention is formed on a substrate. The base material and the composition for preventing water pollution of the present invention may be molded at the same time, for example, integrally molded. Moreover, you may shape | mold a base material after shape | molding the organic-inorganic composite of this invention. Alternatively, the coated product and the base material may be individually molded and then manufactured by adhesion, fusion, or the like.

The following examples, reference examples and comparative examples will specifically explain the present invention, but these do not limit the scope of the present invention.
In Examples, Reference Examples and Comparative Examples, various physical properties were measured by the following methods.
1. Number average particle size The sample was diluted with a suitable solvent so that the solid content in the sample was 1 to 20% by mass, and measured using a wet particle size analyzer (Microtrack UPA-9230 manufactured by Nikkiso).
2. Coating film hardness According to JIS-K5400, it was determined as pencil hardness (film scratch).
3. Transparency Using a Nippon Denshoku Industries turbidimeter NDH2000, haze values and total light transmittance were measured according to JIS-K7105.
4). Contact angle of water to the surface of the coating film A drop of deionized water was placed on the surface of the coating film, left at 23 ° C. for 1 minute, and then measured using a CA-X150 contact angle meter manufactured by Kyowa Interface Science.
The smaller the contact angle of water with the coating film, the higher the hydrophilicity of the coating film surface.
5. Water resistance The sample was immersed in 23 ° C. water for 10 days and then dried at 23 ° C. for 1 day, and the transparency was evaluated by the above method 3.

6). Weather resistance An exposure test (black panel temperature 63 ° C., rainfall 18 minutes / 2 hours) was conducted using a sunshine weather meter manufactured by Suga Test Instruments. The transparency after 500 hours of exposure was evaluated by the above method 3, and the contact angle of water was evaluated by the above method 4.
7). Contamination resistance After the test plate was attached to a fence facing a general road (traffic volume of about 500 to 1000 vehicles / day) for 1 month and 6 months, the degree of contamination was visually evaluated.
○: No dirt, △: Some rain streaks, x: Significant rain streaks Photocatalytic activity After a 5% by mass ethanol solution of methylene blue was applied to the surface of the coating film, the light of FL20S BLB type black light manufactured by Toshiba Lighting & Technology was irradiated for 3 days. At this time, UV intensity measured using a UVR-2 type UV intensity meter manufactured by Topcon, Japan (using a UD-36 type light receiving unit manufactured by Topcon, Japan (corresponding to light having a wavelength of 310 to 400 nm) as the light receiving unit). Was adjusted to 1 mW / cm ² .
Thereafter, the activity of the photocatalyst was evaluated in the following three stages based on the degree of decomposition of methylene blue (based on visual evaluation based on the degree of fading of the coating film surface).
○: Methylene blue is completely decomposed.
Δ: Slightly methylene blue blue remains.
X: Methylene blue was hardly decomposed.

[Adjustment Example 1]
Synthesis of Polymer Emulsion Particle (B2-1) Water Dispersion Into a reactor having a reflux condenser, a dropping tank, a thermometer, and a stirring device, 1750 g of ion-exchanged water and 2 g of dodecylbenzenesulfonic acid were added, and then stirred. The temperature was warmed to 80 ° C. To this, a mixed solution of 86 g of butyl acrylate, 133 g of phenyltrimethoxysilane, 1.3 g of 3-methacryloxypropyltrimethoxysilane, 197 g of diethyl acrylamide, 3 g of acrylic acid, a reactive emulsifier (trade name “Adekaria soap SR-1025 "Asahi Denka Co., Ltd., 25% solid content aqueous solution) 13 g, ammonium persulfate 2 mass% aqueous solution 40 g, ion-exchanged water 1950 g mixed liquid, about 2 with the temperature in the reaction vessel maintained at 80 ℃ It was dripped simultaneously over time. Further, stirring was continued for about 2 hours in a state where the temperature in the reaction vessel was 80 ° C., then cooled to room temperature, filtered through a 100-mesh wire mesh, and the solid content was adjusted to 10.0% by mass with ion-exchanged water. A polymer emulsion particle (B2-1) aqueous dispersion having a number average particle diameter of 100 nm was obtained.

[Adjustment Example 2]
Synthesis of Polymer Emulsion Particle (B2-2) Aqueous Dispersion Into a reactor having a reflux condenser, a dropping tank, a thermometer and a stirrer, 1750 g of ion-exchanged water and 4 g of dodecylbenzenesulfonic acid were added and then stirred. The temperature was warmed to 80 ° C. To this, a mixture of 185 g of dimethyldimethoxysilane and 117 g of phenyltrimethoxysilane was dropped over about 2 hours while maintaining the temperature in the reaction vessel at 80 ° C., and then the temperature in the reaction vessel was 80 ° C. And stirring was continued for about 1 hour. Next, a mixed solution of 86 g of butyl acrylate, 133 g of phenyltrimethoxysilane, 13 g of 3-methacryloxypropyltrimethoxysilane, 197 g of diethylacrylamide, 3 g of acrylic acid, a reactive emulsifier (trade name “ADEKA rear soap SR-1025”, Asahi A mixture of 13 g of Denka Co., Ltd. (25% solid content aqueous solution), 40 g of 2 mass% aqueous solution of ammonium persulfate and 1950 g of ion-exchanged water was kept for about 2 hours while maintaining the temperature in the reaction vessel at 80 ° C. It was dripped simultaneously. Further, stirring was continued for about 2 hours in a state where the temperature in the reaction vessel was 80 ° C., then cooled to room temperature, filtered through a 100-mesh wire mesh, and the solid content was adjusted to 10.0% by mass with ion-exchanged water. A polymer emulsion particle (B2-2) aqueous dispersion having a number average particle diameter of 180 nm was obtained.

[Example 1]
To 100 g of the polymer emulsion particles (B2-1) aqueous dispersion synthesized in Preparation Example 1, a water-dispersed colloidal silica having a number average particle size of 12 nm (trade name “Snowtex O”, manufactured by Nissan Chemical Industries, Ltd., solid content) 20 g) 5 g, silica coated titanium oxide hydrosol (trade name “MPT-422”, manufactured by Ishihara Sangyo Co., Ltd., solid content 20%) 5 g with a number average particle size of 10 nm is mixed and stirred to prevent water pollution. A composition (E-1) was obtained.
After bar coating the composition for water-based contamination prevention (E-1) to a film thickness of 2 μm on a 10 cm × 10 cm polyvinyl chloride film and a polyethylene terephthalate film (Lumirror Q100D, manufactured by Toray Industries, Inc.) A coated product (F-1) was obtained by drying for a week. The evaluation results are shown in Table 1.

[Example 2]
To 100 g of the polymer emulsion particles (B2-2) aqueous dispersion synthesized in Preparation Example 2, water-dispersed colloidal silica having a number average particle size of 12 nm (trade name “Snowtex O”, manufactured by Nissan Chemical Industries, Ltd., solid content 20 g) 5 g, silica coated titanium oxide hydrosol (trade name “MPT-422”, manufactured by Ishihara Sangyo Co., Ltd., solid content 20%) 5 g with a number average particle size of 10 nm is mixed and stirred to prevent water pollution. A composition (E-2) was obtained.
A 10 cm × 10 cm polyvinyl chloride film, a polyvinyl chloride film, and a polyethylene terephthalate film (Lumirror Q100D, manufactured by Toray Industries, Inc.) were bar-coated with the composition for preventing water pollution (E-2) so as to have a film thickness of 2 μm. Thereafter, the coated product (F-2) was obtained by drying at room temperature for 1 week. The evaluation results are shown in Table 1.

[Example 3]
To 100 g of the polymer emulsion particles (B2-2) aqueous dispersion synthesized in Preparation Example 2, water-dispersed colloidal silica having a number average particle size of 12 nm (trade name “Snowtex O”, manufactured by Nissan Chemical Industries, Ltd., solid content 20%) By mixing 5 g, an aqueous pollution control composition (E-3) was obtained.
A 10 cm × 10 cm polyvinyl chloride film, a polyvinyl chloride film, and a polyethylene terephthalate film (Lumirror Q100D, manufactured by Toray Industries, Inc.) were bar-coated with the composition for preventing water-based contamination (E-3) to a thickness of 2 μm. Thereafter, the coated product (F-3) was obtained by drying at room temperature for 1 week. The evaluation results are shown in Table 1.
[Example 4]
After bar coating the 10 cm × 10 cm methacrylic resin plate (Asahi Kasei Chemicals Co., Ltd., Delaglass K) with the aqueous pollution control composition (E-1) prepared in Example 1, room temperature was applied. Was dried for 1 week to obtain a coated product (F-6). The evaluation results are shown in Table 1.

[Comparative Example 1]
To 100 g of the polymer emulsion particles (B2-1) aqueous dispersion synthesized in Preparation Example 1, a silica-coated titanium oxide hydrosol having a number average particle diameter of 10 nm (trade name “MPT-422”, manufactured by Ishihara Sangyo Co., Ltd., solid The composition (E-4) for preventing water pollution was obtained by stirring 5 g).
After coating the above water-based antifouling composition (E-4) to a film thickness of 2 μm on a 10 cm × 10 cm polyvinyl chloride film, it is dried at room temperature for 1 week to give a coated product (F-4) Got. The evaluation results are shown in Table 1.

[Comparative Example 2]
After coating the polymer emulsion particle (B2-1) aqueous dispersion synthesized in Reference Example 1 on a 10 cm × 10 cm polyvinyl chloride film so that the film thickness becomes 2 μm, it is coated by drying at room temperature for 1 week. A product (F-5) was obtained. The evaluation results are shown in Table 1.

  The coated material provided by the present invention, which has excellent weather resistance, water resistance, optical properties and develops stain resistance over a long period of time, is used for outdoor display applications such as marking films, signboards such as surface light emitting plates, sound insulation walls, and displays. Useful.

Claims (11)

An aqueous contamination-preventing composition comprising silica (A) and an aqueous binder (B1),
The water-based binder (B1) is a compound (b1) represented by the following formula (1) containing 3-methacryloxypropyltrimethoxysilane in the presence of water and an emulsifier, N-methylacrylamide, N-methylmethacrylamide, N-ethylacrylamide, N, N-dimethylacrylamide, N, N-dimethylmethacrylamide, N, N-diethylacrylamide, N-ethylmethacrylamide, N-methyl-N-ethylacrylamide, N-methyl-N-ethylmethacryl Amide, N-isopropylacrylamide, Nn-propylacrylamide, N-isopropylmethacrylamide, Nn-propylmethacrylamide, N-methyl-Nn-propylacrylamide, N-methyl-N-isopropylacrylamide, N- Vinyl pyrrolide , N- vinylcaprolactam, N- vinylacetamide, N- methacrylonitrile vinyl monomer having one or more secondary and / or tertiary amide group selected from acryloyl morpholine (b2) and copolymerizable therewith other An aqueous contamination-preventing composition comprising polymer emulsion particles (B2) having a number average particle size of 10 to 800 nm obtained by polymerizing a vinyl monomer (b2 ′).
MR _n W _xn (1)
(In the formula, M represents a metal atom. R represents a linear or branched alkyl group having 1 to 30 carbon atoms, a cycloalkyl group having 5 to 20 carbon atoms, and an unsubstituted or carbon atom. It represents at least one hydrocarbon group selected from an alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms substituted with a halogen atom, and W is carbon. At least one selected from an alkoxy group having 1 to 20 carbon atoms, a hydroxyl group, an acetoxy group having 1 to 20 carbon atoms, a halogen atom, a hydrogen atom, an oxime group having 1 to 20 carbon atoms, an enoxy group, an aminoxy group, and an amide group Represents a group, x represents the valence of the metal atom M, and n represents an integer of 1 to x. Said composition further claim 1 aqueous antifouling composition, wherein the at least one metal oxide selected from metal oxides having photocatalytic activity.   The composition for preventing water pollution according to claim 1 or 2, wherein the polymer emulsion particles (B2) have a core / shell structure. The number average particle size of the silica (A) is 1 to 400 nm.
The composition for water system contamination prevention as described in any one of these.   A coated article comprising a contamination prevention layer formed with the composition for preventing aqueous contamination according to any one of claims 1 to 4 on one side of a substrate.   The coated object according to claim 5, wherein a contact angle at 23 ° C. of the surface of the coated object is 60 degrees or less.   The base material is a resin selected from the group consisting of an acrylic resin, a methacrylic resin, a polyester resin, a polyolefin resin, a polystyrene resin, a polyamide resin, and a polyvinyl chloride resin. Painted material.   The coated object according to any one of claims 5 to 7, wherein the painted object is used for outdoor display.   A marking film comprising a contamination prevention layer formed from the aqueous contamination prevention composition according to any one of claims 1 to 4.   A signboard comprising a contamination prevention layer formed by the water-based contamination prevention composition according to any one of claims 1 to 4.   A sound insulation wall comprising a contamination prevention layer formed by the water-based contamination prevention composition according to any one of claims 1 to 4.