JP2006160880A - Aqueous dispersion, its manufacturing process and water-based stain-resistant coating using the aqueous dispersion - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water-based stain-resistant coating which exhibits a high stain resistance improvement effect from the early stage of the application and maintains the improvement effect for a long period of time. <P>SOLUTION: The water-based stain-resistant coating is of a two pack mixing type and composed of an aqueous dispersion whose constitutional components are a polyorganosiloxane, a condensation product of an organosilane expressed by formula (1), an acrylic polymer and a nonionic water-soluble polymer, an organotin compound expressed by formula (2) or formula (3) and an emulsifier. Formula (1): (R<SP>1</SP>)<SB>4-n</SB>Si(OR<SP>2</SP>)<SB>n</SB>(wherein, R<SP>1</SP>is a hydrogen atom or a monovalent organic group; R<SP>2</SP>is an alkyl grpoup or an acyl group), Formula (2): (R<SP>3</SP>)(R<SP>4</SP>)Sn(R<SP>5</SP>)(R<SP>6</SP>), Formula (3): (R<SP>7</SP>)Sn(R<SP>8</SP>)(R<SP>9</SP>)(R<SP>10</SP>) (wherein, R<SP>3</SP>, R<SP>4</SP>and R<SP>7</SP>are each an alkyl group; R<SP>5</SP>, R<SP>6</SP>, R<SP>8</SP>, R<SP>9</SP>and R<SP>10</SP>are each an organic group having a monovalent ester group). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a water-based antifouling paint capable of forming a coating film excellent in stain resistance, and more specifically, an aqueous dispersion containing a polyorganosiloxane, an acrylic polymer, a nonionic water-soluble polymer, and the like, and an organic The present invention relates to a two-component mixed type antifouling paint composed of an aqueous dispersion containing a tin compound.

  Conventionally, with the background of environmental problems, water-based paints have been used in various fields, and the range of application has been steadily expanding. Along with this situation, a higher performance water-based paint is required. For example, in recent years, when water-based paints are used as exterior wall paints, there is a problem that the paint surface exposed to exhaust gas and dust is stained and becomes ugly, and water-based paints with excellent stain resistance are required. ing.

  As a measure for improving the stain resistance of the water-based paint, for example, a method of adding an organosilicate modified with a polyethylene glycol compound to the water-based paint is disclosed (for example, see Patent Document 1). Such a method is advantageous in that the silanolic hydroxyl group of the phase-separated organosilicate makes the surface of the coating film hydrophilic, thereby lowering the contact angle with water and making it difficult to attach rain stripes. However, this method has a drawback that although the effect of improving the stain resistance at the beginning of coating is high, the effect does not last for a long time.

In addition, the present applicant has already disclosed an aqueous dispersion containing a polyorganosiloxane, an acrylic polymer, and an organic tin compound (see, for example, Patent Document 2). This aqueous dispersion has long-term storage stability and can exhibit excellent stain resistance in a short period after coating, and is useful as an aqueous coating. However, in recent years, there has been a demand for water-based paints that exhibit a higher effect of improving stain resistance from the beginning of painting, and this aqueous dispersion is not sufficient in terms of the effect of improving stain resistance at the beginning of painting. It still left room for improvement.
International Publication No. 99/05228 Pamphlet JP 2004-161782 A

  Thus, at present, as a measure to improve the stain resistance of water-based paints, a higher anti-stain effect is exhibited from the beginning of painting, and it is possible to maintain the anti-stain effect for a long period of time. And what has long-term storage stability has not been disclosed yet. Therefore, the creation of such measures is eagerly desired by the industry.

  The present invention has been made in order to solve the above-described problems of the prior art, and can exhibit a higher antifouling effect from the beginning of coating, and can maintain the antifouling effect for a long period of time. And a water-based antifouling paint having an advantageous effect compared with the prior art that has long-term storage stability, and an aqueous dispersion that can be suitably used for the production thereof and a method for producing the same. Is.

  As a result of intensive studies to solve the problems of the prior art as described above, the present inventors have found that an aqueous dispersion containing a polyorganosiloxane, an acrylic polymer, a nonionic water-soluble polymer, and the like, and an organic tin compound The present invention has been completed by conceiving that the above-mentioned problems can be solved by a two-component mixed aqueous antifouling paint composed of an aqueous dispersion containing an aqueous solution. Specifically, according to the present invention, the following aqueous dispersion, aqueous dispersion manufacturing method, aqueous antifouling paint, painted body manufacturing method, and building material are provided.

[1] In an aqueous medium, a polyorganosiloxane (component A) that is at least one condensate selected from organosilanes (component A ′) represented by the following general formula (1), and a glass transition point of − An acrylic polymer (component B) at 20 ° C. to + 80 ° C. and a nonionic water-soluble polymer and / or an anion group-containing water-soluble polymer (component C) are used as constituent components, and the component A is used as the component A and the component B. 2 to 50 mass% with respect to the total mass of the components, the B component, 50 to 98 mass% with respect to the total mass of the A component and the B component, the C component, the A component and the B component. An aqueous dispersion containing 0.1 to 20 parts by mass with respect to 100 parts by mass in total, in the aqueous medium, a part of the monomer (B ′ component) constituting the component A and the component B, And emulsifier The emulsion is refined to an average particle size of 0.5 μm or less, and then a part of the B ′ component is radical polymerized in the presence of a radical polymerization initiator at pH 4-9. An aqueous dispersion obtained by adding the remainder of the B ′ component to the reaction solution and radical polymerization to form the B component, and then adding and mixing the C component.
(R ¹ ) _4-n Si (OR ² ) _n (1)
(In the formula, R ¹ represents a hydrogen atom or a monovalent organic group, R ² represents an alkyl group or an acyl group, and n is 3 or 4.)

[2] In an aqueous medium, a polyorganosiloxane (component A) which is at least one condensate selected from organosilanes (component A ′) represented by the following general formula (1) and a glass transition point of − An acrylic polymer (component B) at 20 ° C. to + 80 ° C. and a nonionic water-soluble polymer and / or an anion group-containing water-soluble polymer (component C) are used as constituent components, and the component A is used as the component A and the component B. 2 to 50 mass% with respect to the total mass of the components, the B component, 50 to 98 mass% with respect to the total mass of the A component and the B component, the C component, the A component and the B component. A method for producing an aqueous dispersion containing 0.1 to 20 parts by mass with respect to 100 parts by mass of the total mass of the monomer (B ′ component) constituting the A component and the B component in an aqueous medium Mix some and emulsifier After emulsification, the average particle size of the emulsion is refined to 0.5 μm or less, and then obtained by radical polymerization of a part of the B ′ component in the presence of a radical polymerization initiator at pH 4-9. A method for producing an aqueous dispersion in which the remainder of the B ′ component is further added to the reaction liquid to form the B component by radical polymerization, and then the C component is added and mixed.
(R ¹ ) _4-n Si (OR ² ) _n (1)
(In the formula, R ¹ represents a hydrogen atom or a monovalent organic group, R ² represents an alkyl group or an acyl group, and n is 3 or 4.)

[3] An aqueous dispersion containing an organic tin compound (component D) represented by the following general formula (2) or the following general formula (3) and having a molecular weight of 640 or more and an emulsifier in an aqueous medium.
(R ³ ) (R ⁴ ) Sn (R ⁵ ) (R ⁶ ) (2)
(R ⁷ ) Sn (R ⁸ ) (R ⁹ ) (R ¹⁰ ) (3)
(Wherein R ³ , R ⁴ and R ⁷ each represents an alkyl group, and R ⁵ , R ⁶ , R ⁸ , R ⁹ and R ¹⁰ each represents a monovalent organic group having an ester group. Show.)

[4] The aqueous dispersion according to [1] and the aqueous dispersion according to [3], wherein the D component is 100 parts by mass with respect to a total mass of the A component and the B component. A two-component water-based antifouling paint in which the aqueous dispersion described in [1] and the aqueous dispersion described in [3] are mixed so as to be 0.01 to 10 parts by mass.

[5] The aqueous dispersion described in [1] and the aqueous dispersion described in [3] are mixed to produce an aqueous antifouling paint, and the aqueous antifouling paint is applied to the surface of the substrate. The manufacturing method of the coating body which obtains the coating body by which antifouling coating film was formed in the surface of the said base material by doing.

[6] After the aqueous dispersion described in [1] is applied to the surface of the substrate to form a coating layer, the aqueous dispersion described in [3] is further applied to the surface of the coating layer. A method for producing a coated body, wherein a water-based antifouling paint is produced by spraying to obtain a coated body having an antifouling coating film formed on the surface of the substrate.

[7] A building having an antifouling coating film formed on the surface thereof by an aqueous antifouling paint produced from the aqueous dispersion described in [1] and the aqueous dispersion described in [3]. material.

  The water-based antifouling paint of the present invention exhibits a higher effect of improving stain resistance from the beginning of coating, can maintain the effect of improving stain resistance for a long period of time, and has long-term storage stability.

  Hereinafter, the best mode for carrying out the water-based antifouling paint of the present invention will be specifically described. However, the water-based antifouling paint of the present invention is not limited to the following embodiments.

  The water-based antifouling paint of the present invention comprises a water-based dispersion (hereinafter referred to as “first water-based dispersion”) containing polyorganosiloxane, an acrylic polymer, a nonionic water-soluble polymer, and the like, and an organic tin compound. It is a two-component mixed type aqueous antifouling paint composed of an aqueous dispersion (hereinafter referred to as “second aqueous dispersion”).

[1] First aqueous dispersion (main agent)
The first aqueous dispersion is an aqueous dispersion containing polyorganosiloxane, an acrylic polymer, a nonionic water-soluble polymer, and the like. Hereinafter, each component will be described.

Component A: Polyorganosiloxane Component A in the present invention is at least one condensate selected from organosilanes represented by the following general formula (1) (component A ′; hereinafter simply referred to as “organosilane”). is there. The “condensate” mentioned here contains a component in which the silanol group of organosilane produced by hydrolysis is condensed to form a Si—O—Si bond. In other words, the “condensate” here does not need to have all the silanol groups condensed, but also includes a mixture of only a part of the silanol groups or a mixture of those having different degrees of condensation. is there. Moreover, unreacted organosilane may be mixed in the “condensate”.
(R ¹ ) _4-n Si (OR ² ) _n (1)
(In the formula, R ¹ represents a hydrogen atom or a monovalent organic group, R ² represents an alkyl group or an acyl group, and n is 3 or 4.)

In the component A, it is preferable that a part of the OR ² group in the general formula (1) remains without being hydrolyzed. When the OR ² group remains in the component A, the OR ² group is hydrolyzed by rainwater or the like on the surface of the coating film to generate a silanolic hydroxyl group. As a result, the coating film surface is hydrophilized, and the stain resistance is dramatically improved. In this case, the OR ² groups remaining in the component A, other OR ² groups remaining condensate in the formation of Si-O-Si bonds of the OR ² groups not yet hydrolysis in organosilane It is a concept that includes.

The amount of OR ² groups remaining in component A is preferably 50 mol% or more, more preferably 60 mol% or more, based on the theoretical number of moles of OR ² groups possessed by A ′ component (organosilane) before condensation. is there. The amount of the OR ² group remaining in the first aqueous dispersion is preferably 1 to 25 mmol / g, more preferably based on the total mass of the A component and the B component in the first aqueous dispersion. Is 2 to 20 mmol / g. If the amount of OR ² groups remaining in the first aqueous dispersion is less than 1 mmol / g, the stain resistance of the coating film tends to be difficult to improve. On the other hand, when it exceeds 25 mmol / g, the storage stability of the aqueous dispersion tends to decrease.

The amount of the OR ² group remaining in the aqueous dispersion can be adjusted by the amount of the OR ² group in the A component and the quantitative ratio of the A component and the B component. The amount of the OR ² group in the component A or the first aqueous dispersion can be calculated by measuring the amount of alcohol (R ² —OH) generated by hydrolysis with an appropriate catalyst.

In the general formula (1), as the organic group for R ^1, preferably an organic group having 1 to 8 carbon atoms. For example, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, sec-butyl group, t-butyl group, n-hexyl group, n-heptyl group, n- Alkyl groups such as octyl group and 2-ethylhexyl group; acyl groups such as acetyl group, propionyl group, butyryl group, valeryl group, benzoyl group, trioyl group, caproyl group; vinyl group, allyl group, cyclohexyl group, phenyl group, epoxy In addition to a group, a glycidyl group, a (meth) acryloxy group, a ureido group, an amide group, a fluoroacetamide group, an isocyanate group, etc., substituted derivatives of these groups can be exemplified.

Examples of the substituent in the substituted derivative of R ¹ include a halogen atom, a substituted or unsubstituted amino group, a hydroxyl group, a mercapto group, an isocyanate group, a glycidoxy group, a 3,4-epoxycyclohexyl group, and a (meth) acryloyloxy group. Ureido groups, ammonium bases and the like. However, the number of carbon atoms in R ¹ consisting of substituted derivatives thereof is preferably, including carbon atoms in a substituent group is 8 or less.

Moreover, as an alkyl group of R < ² >, a C1-C5 alkyl group is preferable. For example, a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group, a sec-butyl group, a t-butyl group, an n-pentyl group, and the like can be given. On the other hand, the acyl group of R ² is preferably an acyl group having 1 to 6 carbon atoms. For example, an acetyl group, a propionyl group, a butyryl group, a valeryl group, and the like can be given. A plurality of R ² present in the general formula (1) may be the same as or different from each other. N in the general formula (1) needs to be 3 or 4. When this n is 2 or less, the stain resistance of the coating film tends to be hardly improved.

  Specific examples of n = 4 organosilane (tetrasubstituted organosilane) include tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-i-propoxysilane, tetra-n-butoxysilane and the like. Can do.

  Specific examples of n = 3 organosilane (trisubstituted organosilane) include methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, and n-propyl. Triethoxysilane, i-propyltrimethoxysilane, i-propyltriethoxysilane, n-butyltrimethoxysilane, n-butyltriethoxysilane, n-pentyltrimethoxysilane, n-hexyltrimethoxysilane, n-heptyltri Methoxysilane, n-octyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, cyclohexyltrimethoxysilane, cyclohexyltriethoxysilane,

  Phenyltrimethoxysilane, phenyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 3,3,3-trifluoropropyltriethoxy Silane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-hydroxyethyltrimethoxysilane, 2-hydroxyethyltriethoxysilane, 2-hydroxypropyltrimethoxysilane, 2-hydroxypropyltriethoxysilane, 3-hydroxypropyltrimethoxysilane, 3-hydroxypropyltriethoxysilane,

  3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropyl Triethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 3- (meth) acryloxypropyltrimethoxysilane, 3- (meta ) Atacrylyloxypropyltriethoxysilane, 3-ureidopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane and the like.

  When manufacturing A component, organosilane can be used individually or in mixture of 2 or more types. Among the above organosilanes, it is preferable to use a tetrasubstituted organosilane alone. When the tetrasubstituted organosilane is used alone, silanolic hydroxyl groups on the surface of the coating film increase, so that the surface of the coating film is easily hydrophilized and there is an advantage that the effect of improving stain resistance is high. However, it is also possible to use a mixture of tetrasubstituted organosilane and trisubstituted organosilane.

  The structural unit derived from the tetrasubstituted organosilane is usually 2 to 100 mol%, preferably 5 to 80 mol%, more preferably 50 to 80 mol%, based on the total number of moles of all the structural units constituting the component A. The structural unit derived from trisubstituted organosilane is usually 98 to 0 mol%, preferably 95 to 20 mol%, more preferably 50 to 20 mol%. When the n = 4 constitutional unit is less than 2 mol%, the stain resistance tends to decrease. In addition, when the thing comprised only from the structural unit derived from trisubstituted organosilane is used as a condensate of organosilane, the silanol-type hydroxyl group on the coating-film surface will reduce. As a result, the surface of the coating film is hardly hydrophilized, and the stain resistance tends not to be improved.

  The component A can be produced by hydrolyzing the organosilane in advance and then condensing it. In the hydrolysis / condensation reaction, it is preferable to add an appropriate amount of water and a hydrolysis / condensation catalyst described later to the organosilane, and further add an organic solvent as necessary to cause the reaction. In this case, the usage-amount of water is 1.2-3.0 mol normally with respect to 1 mol of organosilane, Preferably it is about 1.3-2.0 mol.

  Examples of the hydrolysis / condensation catalyst include acidic compounds, alkaline compounds, salt compounds, amine compounds, and organometallic compounds. By adding these as a catalyst, the contamination resistance can be expressed earlier. Examples of acidic compounds include acetic acid and dodecylbenzenesulfonic acid; examples of alkaline compounds include sodium hydroxide and potassium hydroxide; examples of salt compounds include alkalis such as naphthenic acid, octylic acid, nitrous acid, sulfurous acid, aluminate, and carbonic acid. Metal salts, etc .; As amine compounds, alkylamines (ethylenediamine, etc.), quaternary ammonium salts, aminoalkylsilanes (3-aminopropyltrimethoxysilane, etc.), etc .; Organometallic compounds, organic zirconium compounds ( Tri-n-butoxyethyl acetoacetate zirconium, etc.), organic titanium compounds (di-i-propoxybis (acetylacetonato) titanium, etc.), organic aluminum compounds (di-i-propoxyethyl acetoacetate aluminum, etc.), etc. are preferred. Can be used for

  The addition amount of the hydrolysis / condensation catalyst is usually 0.01 to 5 parts by mass, preferably 0.1 to 5 parts by mass, and more preferably 0 to 100 parts by mass of the total mass of the component A and the component B. 0.1 to 3 parts by mass. When the addition amount exceeds 5 parts by mass, cracks tend to occur in the coating film.

  The organic solvent used as necessary is not particularly limited as long as it is uniformly compatible with an organosilane condensate and a component B (acrylic polymer) described later. For example, alcohols, aromatic hydrocarbons, ethers, ketones, esters and the like can be mentioned.

  Specific examples of the alcohols include methyl alcohol, ethyl alcohol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, sec-butyl alcohol, t-butyl alcohol, n-hexyl alcohol, n-octyl alcohol, Examples thereof include ethylene glycol, diethylene glycol, triethylene glycol, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene monomethyl ether acetate, diacetone alcohol and the like.

  Specific examples of the aromatic hydrocarbons include benzene, toluene and xylene, specific examples of the ethers include tetrahydrofuran and dioxane, and specific examples of the ketones include acetone, methyl ethyl ketone, and methyl isobutyl. Specific examples of esters such as ketone and diisobutyl ketone include ethyl acetate, n-propyl acetate, butyl acetate, and propylene carbonate.

  These organic solvents can be used alone or in admixture of two or more. When the organosilane condensate contains an organic solvent, it is preferable to remove the organic solvent from the aqueous medium before radical polymerization described later.

  The average condensation degree of A component is 6-1000 mer normally, Preferably it is 8-500 mer. When the average degree of condensation is less than hexamer, the polymerization stability and storage stability tend to decrease. On the other hand, when it exceeds 1000 mer, the transparency of the coating film tends to decrease. In this case, as long as the average condensation degree as the whole component A is within the above range, the component A exceeds organosilane which is not hydrolyzed / condensed, organosilane 2 to 5 mer, 1000 mer. A condensate may be included. In addition, the average condensation degree here shall mean the average condensation degree computed from the weight average molecular weight measured by liquid chromatography. The average condensation degree of A component can be adjusted with the quantity of the water used in the case of hydrolysis and condensation of organosilane.

  As the component A, commercially available products may be used in addition to those synthesized as described above. Examples of commercially available products of polyorganosiloxane include MKC silicate (trade name: manufactured by Mitsubishi Chemical Corporation), ethyl silicate (trade name: manufactured by Tama Chemical Industry Co., Ltd.), ethyl silicate (trade name: manufactured by Colcoat Co.), silicone resin ( Product name: Toray Dow Corning Silicone Co., Ltd., Silicone Resin (Product Name: GE Toshiba Silicone Co., Ltd.), Silicone Resin (Product Name: Shin-Etsu Chemical Co., Ltd.), Silicone Oligomer (Product Name: Nihon Unica Co., Ltd.) Etc. These may be used as they are, or further condensed.

  Moreover, as a commercial product of polyorganosiloxane having an average degree of condensation of organosilane of hexamer or more, silicate 45 and silicate 48 (all trade names: manufactured by Tama Chemical Industry Co., Ltd.) are used as condensates of tetrasubstituted organosilanes. SR2402, DC3037, DC3074 (all trade names: manufactured by Toray Dow Corning Silicone Co., Ltd.); X40-9220, X40; -9225 (all trade names: manufactured by Shin-Etsu Chemical Co., Ltd.); TSR165 (trade name: manufactured by GE Toshiba Silicone) and the like.

  On the other hand, as a commercial product of polyorganosiloxane having an average degree of condensation of organosilane of less than hexamer, silicate 40 and M silicate 51 (all trade names: manufactured by Tama Chemical Industries, Ltd.) ); Ethyl silicate 40, methyl silicate 51 (all trade names: manufactured by Colcoat); MS51 (trade name: manufactured by Mitsubishi Chemical Corporation), and the like.

  In the present invention, the polyorganosiloxane of component A can be used alone or in admixture of two or more. The usage-amount of A component in a 1st aqueous dispersion is 2-50 mass% with respect to the total mass of A component and B component, Preferably it is 10-30 mass%, More preferably, it is 15-25 mass%. . If the amount used is less than 2% by mass, the contamination resistance tends to be difficult to improve. On the other hand, when it exceeds 50 mass%, the storage stability of the aqueous dispersion may be lowered.

B component: Acrylic polymer The B component in the present invention is a polymer obtained by polymerizing the B ′ component (monomer constituting the B component), and the monomer of the B ′ component contains an acrylic monomer. Usually, as the monomer for the B ′ component, a radical polymerizable monomer is used, and the B component: acrylic polymer is formed by radical polymerization of the monomer.

  Examples of the acrylic monomer contained in the B ′ component include (meth) acrylates such as ammonium (meth) acrylate, sodium (meth) acrylate, potassium (meth) acrylate; methyl (meth) acrylate, ethyl (Meth) acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, t-butyl (meth) acrylate, n-pentyl (meta ) Acrylate, i-pentyl (meth) acrylate, n-hexyl (meth) acrylate, n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, cyclohexyl (meth) acrylate, Such as isobonyl (meth) acrylate Meth) acrylate; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) hydroxyl group-containing (meth) acrylic acid esters such as acrylate;

  Ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, Tripropylene glycol di (meth) acrylate, tetrapropylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate Polyfunctional (meth) acrylic esters such as pentaerythritol tetra (meth) acrylate; 2,2,2-trifluoroethyl (meth) acrylate, 1H, 1H-pen Fluorine-containing (meth) acrylic esters such as deca fluoro -n- octyl (meth) acrylate; glycidyl (meth) an epoxy group-containing (meth) acrylic acid esters such as acrylate, and the like.

  Among these acrylic monomers, (meth) acrylic acid esters and hydroxyl group-containing (meth) acrylic acid esters are preferably used, and n-butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, t-butyl methacrylate, More preferably, cyclohexyl methacrylate, 2-hydroxyethyl methacrylate and the like are used. The acrylic monomers can be used alone or in admixture of two or more.

  The B ′ component may contain other radical polymerizable monomer in addition to the acrylic monomer.

  Examples of other radical polymerizable monomers include styrene, α-methyl styrene, 2-methyl styrene, 3-methyl styrene, 4-methyl styrene, 4-ethyl styrene, 4-t-butyl styrene, and 2-hydroxymethyl styrene. 3-hydroxymethylstyrene, 4-hydroxymethylstyrene, 4-methoxystyrene, 4-ethoxystyrene, 3,4-dimethylstyrene, 3,4-diethylstyrene, 2-chlorostyrene, 3-chlorostyrene, 4-chloro Aromatic vinyl monomers such as styrene, 3-methyl-4-chlorostyrene, 2,4-dichlorostyrene, 2,6-dichlorostyrene, 1-vinylnaphthalene; polyfunctional (meth) acrylic acid such as divinylbenzene Multifunctional monomers other than esters;

  Unsaturated amide compounds such as (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, Nn-butoxymethyl (meth) acrylamide, N, N′-methylenebisacrylamide; ) Vinyl cyanide compounds such as acrylonitrile; dicaprolactone, and the like.

  Further, as another radical polymerizable monomer, a monomer having a dialkylamide group or a monomer having a polyoxyethylene chain may be used. Examples of the monomer having a dialkylamide group include N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N, N-di-n-propyl (meth) acrylamide, and N, N-di N, N-dialkyl (meth) acrylamides such as -i-propyl (meth) acrylamide can be mentioned. Among these, it is preferable to use N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide or the like.

  Examples of the monomer having a polyoxyethylene chain include (meth) acrylic acid esters having a polyoxyethylene chain. Among them, a monomer having a polyoxyethylene chain having 2 to 30 oxyethylene units is used. It is preferable. Commercially available products of such monomers include BLEMMER PE-90, PE-200, PE-350, PME-100, PME-200, PME-400, AE-350 (all trade names: manufactured by NOF Corporation); MA-30, MA-50, MA-100, MA-150, RA-1120, RA-2614, RMA-564, RMA-568, RMA-1114, MPG130-MA (all trade names: manufactured by Nippon Emulsifier Co., Ltd.) Etc.

  Furthermore, a radical polymerizable monomer having a formyl group and / or a keto group can also be used as another radical polymerizable monomer. Examples of the radical polymerizable monomer having a formyl group and / or keto group include diacetone (meth) acrylamide; vinyl methyl ketone, vinyl ethyl ketone, vinyl n-propyl ketone, vinyl i-propyl ketone, vinyl n- Vinyl alkyl ketones having 4 to 7 carbon atoms in the alkyl group such as butyl ketone, vinyl-i-butyl ketone, vinyl-t-butyl ketone, and vinyl ketones such as vinyl phenyl ketone, vinyl benzyl ketone, and divinyl ketone;

  Diacetone (meth) acrylylate, acetonitrile (meth) acrylylate, 2-hydroxypropyl (meth) acrylylate-acetyl acetate, 3-hydroxypropyl (meth) acrylylate-acetylacetate, 2-hydroxybutyl (meth) acrylylate- Formyl groups such as acetyl acetate, 3-hydroxybutyl (meth) acrylylate-acetylacetate, 4-hydroxybutyl (meth) acrylylate-acetylacetate, butanediol-1,4- (meth) acrylyllate-acetylacetate, and / or Alternatively, (meth) acrylic acid esters having a keto group can be mentioned.

  Furthermore, as other radical polymerizable monomer, a radical polymerizable compound among a component having an ultraviolet absorbing action, a component having a light stabilizing action, or a silane coupling agent may be used. Details of these components will be described later.

  In addition, as a monomer contained in the B ′ component, when a monomer that exhibits acidity alone or a monomer that exhibits basicity alone is used, it is preferably used after neutralizing these monomers.

  Examples of the “monomer showing acidity alone” include unsaturated carboxylic acids such as (meth) acrylic acid, crotonic acid, maleic acid, fumaric acid and itaconic acid; unsaturated carboxylic acids such as maleic anhydride and itaconic anhydride Anhydrides etc. can be mentioned. These monomers can be neutralized with ammonia, non-radically polymerizable amino compounds, alkaline substances such as metal hydroxides such as sodium hydroxide, etc. It is preferable to use it.

  Examples of the “monomer that exhibits basicity alone” include 2-aminoethyl (meth) acrylate, 2-dimethylaminoethyl (meth) acrylate, 2-diethylaminoethyl (meth) acrylate, and 2-aminopropyl (meth) acrylate. Aminoalkyl group-containing (meth) acrylic acid esters such as 3-aminopropyl (meth) acrylate, 2-dimethylaminopropyl (meth) acrylate, 3-dimethylaminopropyl (meth) acrylate, etc .; Amino group-containing vinyl monomers; 1,1,1-trimethylamine (meth) acrylimide, 1-methyl-1-ethylamine (meth) acrylimide, 1,1-dimethyl-1- (2-hydroxypropyl) amine (meth ) Acrylic imide, 1,1-dimethyl Contains amine imide groups such as ru-1- (2-phenyl-2-hydroxyethyl) amine (meth) acrylimide, 1,1-dimethyl-1- (2-hydroxy-2-phenoxypropyl) amine (meth) acrylimide A vinyl-type monomer etc. can be mentioned. These monomers are preferably used after neutralization with inorganic acids such as hydrochloric acid and sulfuric acid, organic acids such as acetic acid, the above-mentioned “monomer that exhibits acidity alone”, and the like.

  The content of the acrylic monomer in the B ′ component is usually 30 to 100% by mass, preferably 40 to 98% by mass, and more preferably 50 to 95% with respect to the total mass of all the constituent monomers in the B ′ component. % By mass. When the acrylic monomer content is less than 30% by mass, the weather resistance of the coating film tends to decrease.

The glass transition point of B component needs to be -20 degreeC-+80 degreeC, it is preferable that it is 0-60 degreeC, and it is more preferable that it is 10-40 degreeC. When the glass transition point is lower than −20 ° C., the stain resistance tends to be difficult to be improved. On the other hand, when it exceeds 80 degreeC, there exists a tendency for it to become easy to produce a crack in a coating film. Here, the “glass transition point” means a glass transition point (theoretical value) calculated using the Fox formula shown in the following formula (4) for the monomers X, Y, Z,. It shall be. The glass transition point of the B component can be adjusted by appropriately changing the type, combination, or ratio of the constituent monomers. Moreover, the polystyrene conversion weight average molecular weight of B component is 10,000-1 million normally, Preferably it is 100,000-1 million.
1 / TgB = (a / TgX) + (b / TgY) + (c / TgZ) + (4)
(However, TgB: B glass transition point (K), TgX: X homopolymer glass transition point (K), TgY: Y homopolymer glass transition point (K), TgZ: Z homopolymer Glass transition point (K), a: mass fraction of X, b: mass fraction of Y, c: mass fraction of Z)

  In the present invention, the acrylic polymer of component B can be used alone or in admixture of two or more. The usage-amount of B component in a 1st aqueous dispersion is 50-98 mass% with respect to the total mass of A component and B component, Preferably it is 60-90 mass%, More preferably, it is 65-85 mass%. If the usage-amount of B component is less than 50 mass%, the reaction stability at the time of radical polymerization and the storage stability of an aqueous dispersion may fall. On the other hand, when it exceeds 98 mass%, there exists a tendency for contamination resistance to be hard to be improved.

Component C: Nonionic water-soluble polymer and / or anion group-containing water-soluble polymer Component C in the present invention makes the coating film surface hydrophilic and reduces the contact angle between the coating film surface and water, thereby making it resistant to contamination. It is a component for improving.

  Nonionic water-soluble polymers include, for example, polyethylene glycol, polypropylene glycol, polyglycerin, polyethylene glycol fatty acid ester, polyglycols such as polyethylene glycol (mono, di) alkyl ether and derivatives thereof; hydroxyethyl cellulose, hydroxymethyl cellulose, hydroxypropyl cellulose And water-soluble cellulose derivatives such as carboxymethylcellulose; polyvinyl alcohol, and the like. Examples of the anionic group-containing water-soluble polymer include water-soluble polyacrylate, water-soluble polyurethane, and water-soluble polyacrylamide.

  In the present invention, the nonionic water-soluble polymer and / or the anionic group-containing water-soluble polymer of component C can be used alone or in admixture of two or more. The usage-amount of C component in a 1st aqueous dispersion is 0.1-20 mass parts with respect to 100 mass parts of total mass of A component and B component, Preferably it is 1-10 mass parts, More preferably, it is 2-8. Part by mass. If the usage-amount of C component is less than 0.1 mass part, the effect which makes the coating-film surface hydrophilic will be scarce, and there exists a possibility that the contamination-resistant improvement effect may become inadequate. On the other hand, when it exceeds 20% by mass, the surface of the coating film becomes too hydrophilic, the water resistance of the coating film decreases, and it may be difficult to maintain the effect of improving the stain resistance for a long period of time.

  In the aqueous medium, the first aqueous dispersion is emulsified by mixing a component A: polyorganosiloxane, B ′ component: a part of the monomer constituting the B component (acrylic polymer), and an emulsifier, With respect to the reaction liquid obtained by refining the average particle diameter of the emulsion to 0.5 μm or less and then radically polymerizing a part of the B ′ component at pH 4 to 9 in the presence of a radical polymerization initiator, Furthermore, after forming the said B component by adding the remainder of B 'component and carrying out radical polymerization, it adds C component and is obtained by mixing.

When the first aqueous dispersion is prepared by such a method, a relatively high concentration of the component A is obtained as a composite particle which is compatible with the component B. Therefore, hydrolysis of the OR ² group in the component A during storage of the first aqueous dispersion is suppressed, and storage stability can be improved. Further, the transparency and surface gloss of the coating film to be formed are improved, and the stain resistance can be maintained for a long time. Furthermore, since the polymerization stability is good, it has the advantage of being excellent in the warm water resistance of the coating film.

  In addition, radical polymerization of the B ′ component after the refinement of the emulsion employed in this method can be said to be one type of miniemulsion polymerization, and has the following advantages that cannot be obtained by a conventionally known method. .

(I) Since the hydrolysis / condensation reaction of the A component does not proceed during the radical polymerization of the B ′ component, it is a low molecular weight alkoxysilane hydrolyzate or a by-product of the hydrolysis reaction that becomes an inhibitor of the polymerization. Some alcohol is rarely generated. As a result, the dispersion state of the monomer oil droplets in the emulsion is stable, and radical polymerization proceeds stably even if a relatively large amount of component A is contained.

(Ii) Since the radical polymerization of the B ′ component proceeds in the presence of the A component in the emulsion particles, a structure in which the A component is extremely finely dispersed in the B component is formed. As a result, even if methyl polyorganosiloxane having poor compatibility is used as the siloxane component, a coating film having excellent transparency can be formed.

(Iii) In the emulsion particles, since the polymers coexist in a solvent-free state, the degree of freedom of the OR ² group in the siloxane component is limited, and the reaction activity is reduced. As a result, hydrolysis of the highly reactive OR ² group is suppressed, and storage stability is improved.

(Iv) Since a certain amount or more of the OR ² group having a specific structure is contained in the component A, the OR ² group is restrained in a good state in the emulsion particles, while its high reaction activity is preserved. As a result, the hydrolysis proceeds from the surface after the coating film is formed, so that the hydrophilicity is quickly expressed and the hydrophilicity is maintained for a long time. Therefore, an extremely excellent antifouling effect can be exhibited.

  By the way, when manufacturing a polymer emulsion, many are manufactured by emulsion polymerization. In general emulsion polymerization, polymerization proceeds from a large monomer oil droplet having a particle size of several μm to several mm while the monomer molecule moves through an aqueous medium to an emulsifier micelle having a particle size of several nm. Polymer particles with a particle size of several hundred nm are produced. On the other hand, the mini-emulsion polymerization as described above is a method in which monomer oil droplets are finely emulsified in advance to a desired particle size, and the polymerization proceeds and is completed with the particle size. That is, it is a polymerization method that is used particularly when a hydrophobic monomer is polymerized because it does not require movement of monomer molecules in an aqueous medium. By preparing the first aqueous dispersion by miniemulsion polymerization, it is possible to prepare an aqueous dispersion containing many components A with good polymerization stability.

  In addition, radical polymerization in which the B ′ component is added in two stages is a kind of core / shell polymerization. According to this method, the core particles formed from the A component and the B component (derived from the initially added B ′ component) and the B component (derived from the added B ′ component) Polymer particles (core-shell particles) having a two-layer structure composed of a shell portion covering the core are obtained. In such a core-shell particle, since the A component of the core particle is protected by the shell portion formed from the B component, hydrolysis of the A component in the presence of water is more effectively suppressed, and the aqueous dispersion Is further improved in storage stability.

  Under the present circumstances, it is preferable that it is 2: 98-70: 30 as mass ratio of B 'component added initially and B' component added, and it is still more preferable that it is 5: 95-50: 50. . If the mass ratio is less than 2:98, the stain resistance of the coating film tends to be difficult to improve. On the other hand, when it exceeds 70:30, there exists a tendency for the storage stability of an aqueous dispersion to fall.

  The aqueous medium in this method means a medium mainly composed of water. The usage-amount of water is 50-2000 mass parts normally with respect to 100 mass parts of total mass of A component and B 'component, Preferably it is 80-1000 mass parts, More preferably, it is 100-500 mass parts. When the amount of water used is less than 50 parts by mass, emulsification tends to be difficult, and the dispersion stability of the emulsion tends to decrease. On the other hand, if it exceeds 2000 parts by mass, the productivity may decrease.

  Examples of emulsifiers in radical polymerization include anionic surfactants such as alkyl sulfates, alkylaryl sulfates, alkyl phosphates, and fatty acid salts; cationic interfaces such as alkylamines and alkyl quaternary amines. Activators: Nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkyl aryl ethers, block-type polyethers; amphoteric interfaces such as carboxylic acid types (for example, amino acid types, betainic acid types) and sulfonic acid types In addition to the activator, all of the following trade names are latemul S-180A (manufactured by Kao Corporation); Eleminol JS-2 (manufactured by Sanyo Kasei Co., Ltd.); Aqualon KH-10 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.); 10N, SR-10N (above, manufactured by Asahi Denka Kogyo Co., Ltd.); Antox MS-60 (Sun Manufactured Nyukazai); Safuma FP-120 (can be used by Toho Chemical Industry Co., Ltd.) reactivity, such as emulsifiers and the like. Among these, reactive emulsifiers are preferable in that a coating film excellent in weather resistance and water resistance can be obtained.

  An emulsifier can be used individually or in mixture of 2 or more types. The use amount of the emulsifier is usually 0.1 to 5 parts by mass, preferably 0.2 to 4 parts by mass with respect to 100 parts by mass of the total mass of the A and B components during radical polymerization of the B ′ component. More preferably, it is 0.5 to 3 parts by mass. When the amount used is less than 0.1 parts by mass, uniform emulsion formation tends to be difficult, and the reaction stability during radical polymerization tends to decrease. On the other hand, if it exceeds 5 parts by mass, foaming becomes a problem and workability tends to decrease.

  Examples of the radical polymerization initiator used for radical polymerization include water-soluble initiators such as hydrogen peroxide, t-butyl hydroperoxide, and 2,2′-azobis [2-N-benzylamidino] propane hydrochloride; Oil-soluble initiators such as benzoyl peroxide, cumene hydroperoxide, diisopropyl peroxydicarbonate, cumyl peroxyneodecanoate, cumyl peroxy octoate, azobisisobutyronitrile; peroxide initiators and Rongalite And redox initiators that are used in combination with a reducing agent such as sodium ascorbate. Among these, an oil-soluble initiator is preferable from the viewpoint of polymerization stability. On the other hand, it is preferable not to use persulfates such as potassium persulfate, sodium persulfate, ammonium persulfate, t-butyl peroxymaleic acid, succinic acid peroxide and the like that make the pH acidic.

  These radical polymerization initiators can be used alone or in admixture of two or more. The usage-amount of a radical polymerization initiator is 0.01-8 mass parts normally with respect to 100 mass parts of total mass of A component and B component, Preferably it is 0.05-6 mass parts, More preferably, it is 0.1. -5 parts by mass. If the amount used is less than 0.01 parts by mass, the radical polymerization reaction may be deactivated in the middle. On the other hand, when it exceeds 5 mass parts, there exists a possibility that a weather resistance may fall.

  The first aqueous dispersion is preferably blended with a component having an ultraviolet absorption action and / or a light stabilization action (hereinafter referred to as “ultraviolet absorption / light stabilization ingredient”). The ultraviolet light absorbing / stabilizing component is derived from a component that is essentially separated from the B component and a compound used as another monomer in the B ′ component, and is a structural unit of the B component. It is a concept that encompasses both of them.

  Examples of the UV absorption / light stabilization component include organic UV absorbers such as oxalic anilide, salicylic acid, benzophenone, triazine, benzotriazole, and cyanoacrylate; titanium oxide, zinc oxide, cerium oxide, etc. Inorganic UV absorbers; light stabilizers such as organic nickel compounds and hindered amines, etc., and have UV absorption and / or light stabilization that can be used for paints, synthetic rubbers, synthetic resins and synthetic fibers. Any thing can be used.

  Among these UV absorption / light stabilization components, triazine, benzotriazole or cyanoacrylate organic UV absorbers; inorganic UV absorbers consisting of zinc oxide fine particles or cerium oxide fine particles; and hindered amine light stabilization At least one selected from the group of agents is preferred. The average particle size of the zinc oxide fine particles and the cerium oxide fine particles is usually 0.003 to 0.5 μm, preferably 0.005 to 0.2 μm.

  The said ultraviolet absorption and light stabilization component can be used individually or in mixture of 2 or more types. The compounding amount of the ultraviolet absorbing / light stabilizing component is usually 0.1 to 10 parts by mass, preferably 0.2 to 5 parts by mass with respect to 100 parts by mass of the total solid content of the aqueous dispersion. is there.

  The first aqueous dispersion includes a silane cup having both a polymerizable unsaturated group capable of radical copolymerization with the B ′ component and a group capable of forming a siloxane bond such as an alkoxysilyl group capable of cocondensation with the A component. A ring agent can be blended. By adding a silane coupling agent to the aqueous dispersion of the present invention, the hybrid property of the organic component and the inorganic component in the aqueous dispersion is improved, so that the crack resistance, transparency and weather resistance are further improved. Can do.

  Examples of the silane coupling agent include a vinyl group-containing silane coupling agent and a (meth) acryloyloxy group-containing silane coupling agent. These silane coupling agents can be used alone or in admixture of two or more. The compounding amount of the silane coupling agent is usually 20 parts by mass or less, preferably 10 parts by mass or less with respect to 100 parts by mass of the total mass of the A component and the B ′ component (or B component).

  The silane coupling agent may be added before emulsification of the A component and the B ′ component, may be added during radical polymerization, or may be added after the preparation of the aqueous dispersion. When it is added before emulsification, it may be added in advance to the A component or the B ′ component, or may be added to a mixed solution obtained by mixing the A component and the B ′ component. In these, it is preferable to add to the liquid mixture which mixed A component and B 'component before emulsification.

  In the preparation of the first aqueous dispersion, in mixing and emulsifying the respective components, stirring may be performed so that the mixture of the respective components is in a liquid state at a temperature and pressure so as to be in a uniform mixed state visually. . Further, when the emulsion is refined, the average particle size of the emulsion is 0.5 μm or less, preferably 0.05 by treating with mechanical or physical means such as a high-pressure homogenizer, homomixer, or ultrasonic wave. To 0.2 μm. If the average particle size of the emulsion exceeds 0.5 μm, the water resistance may be insufficient.

The reaction temperature in radical polymerization is usually 25 to 100 ° C, preferably 40 to 90 ° C. The reaction time is usually 0.5 to 15 hours, preferably 1 to 8 hours. Moreover, pH at the time of radical polymerization and pH after radical polymerization are 4-9, Preferably it is 5-8. Even if the pH at the time of radical polymerization is lower than 4 or higher than 9, the reaction stability at the time of radical polymerization and the storage stability of the aqueous dispersion may be lowered. Moreover, even if the pH after radical polymerization is lower than 4 or higher than 9, the storage stability of the aqueous dispersion may decrease. Furthermore, during radical polymerization, preferably even after radical polymerization, the pH is adjusted to 4 to 9, preferably 5 to 8, so that the OR ² group in the component A remains without being hydrolyzed. Then, after forming a coating film OR ² group is shifted to the coating surface, the result being hydrolyzed by rainwater, the coating film surface is hydrophilized. Thereby, contamination resistance can be improved drastically.

  When the A component or B ′ component used for the preparation of the first aqueous dispersion has an acidic group such as a carboxyl group or a carboxylic anhydride group, at least one basic compound is added after radical polymerization. Thus, it is preferable to adjust the pH within the above range. Moreover, when each said component has basic groups, such as an amino group and an amine imide group, it is preferable after radical polymerization to add at least 1 sort (s) of acidic compound and to adjust pH in the said range. Further, when each of the components has both an acidic group and a basic group, after radical polymerization, at least one basic compound or acidic compound is added according to the ratio of these groups, and the pH is adjusted. It is preferable to adjust within the said range. In either case, the hydrophilicity of the resulting polymer particles can be increased to improve dispersibility, and hydrolysis of the A component during storage can be prevented.

  Examples of the basic compound include amines such as ammonia, methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, ethanolamine, diethanolamine, and dimethylaminoethanol; alkaline metal water such as potassium hydroxide and sodium hydroxide. An oxide etc. can be mentioned. These basic compounds can be used alone or in admixture of two or more.

  Examples of the acidic compound include inorganic acids such as hydrochloric acid, phosphoric acid, sulfuric acid, and nitric acid; formic acid, acetic acid, propionic acid, lactic acid, oxalic acid, citric acid, adipic acid, (meth) acrylic acid, maleic acid, Examples thereof include organic acids such as fumaric acid and itaconic acid. These acidic compounds can be used alone or in admixture of two or more.

  The dispersion state of the first aqueous dispersion is usually in the form of particles or sol. The average particle size of the polymer particles in the aqueous dispersion is usually 0.01 to 0.5 μm, preferably 0.05 to 0.2 μm. Moreover, the solid content concentration of the aqueous dispersion of the present invention is usually 10 to 60% by mass, preferably 20 to 50% by mass, based on the total mass of the aqueous dispersion. This solid content concentration can be normally adjusted with the quantity of the water used as an aqueous medium.

The aqueous medium in the first aqueous dispersion consists essentially of water, but when the OR ² group in component A is hydrolyzed, it contains alcohol (R ² —OH). If the alcohol content in the aqueous medium becomes too high, the reaction stability at the time of radical polymerization may be lowered, and the contamination resistance may not be sufficiently improved. Therefore, in the present invention, the alcohol content in the aqueous medium during radical polymerization and after radical polymerization is preferably 2% by mass or less with respect to the total mass of the aqueous dispersion. If the alcohol content exceeds 2% by mass, the surface of the coating film may be clouded.

  When the alcohol content in the aqueous medium is too high, for example, after radical polymerization, the pH is adjusted as necessary, and then treatment such as addition of water and separation and removal of alcohol is performed. As a method for separating and removing alcohol in the aqueous medium, for example, a method using an evaporator, a method using a centrifugal thin film evaporator (for example, trade name: EVAPOL, manufactured by Okawara Seisakusho), an external circulation type device (for example, trade name: Examples thereof include a method using a bubbling method (manufactured by Nisso Engineering Co., Ltd.), a method using a falling film type device, a method using a stirring thin film type device (for example, trade name: Wiperene, manufactured by Shinko Pantech Co., Ltd.), and the like.

  Among these methods, the method using an evaporator is preferable in that an additional device is not required, and the method using a centrifugal thin film evaporator and the method using an external circulation device are preferable in terms of industrial production efficiency. In addition, the solid content concentration of the aqueous dispersion can be increased by volatilizing or evaporating the water simultaneously with the separation and removal of the alcohol within a range not impairing the storage stability of the aqueous dispersion. Even when the alcohol content is within a desirable range, the solid content concentration of the aqueous dispersion may be adjusted by adding water, volatilizing or evaporating water, or the like.

[2] Second aqueous dispersion (curing agent)
The second aqueous dispersion is an aqueous dispersion containing an organotin compound and an emulsifier. Hereinafter, each component will be described.

D component: Organotin compound The D component in the present invention is represented by the following general formula (2) or (3), and comprises a compound having a molecular weight of 640 or more, preferably 700 or more.
(R ³ ) (R ⁴ ) Sn (R ⁵ ) (R ⁶ ) (2)
(R ⁷ ) Sn (R ⁸ ) (R ⁹ ) (R ¹⁰ ) (3)
(Wherein R ³ , R ⁴ and R ⁷ each represents an alkyl group, and R ⁵ , R ⁶ , R ⁸ , R ⁹ and R ¹⁰ each represents a monovalent organic group having an ester group. )

When the molecular weight of the D component is less than 640, the storage stability of the D component itself may be inferior, and the storage stability of the aqueous dispersion may be lowered. In addition, the upper limit of the molecular weight of D component is about 5000 normally, Preferably it is about 2000 from viewpoints, such as availability and a handleability. The alkyl group of R ³ , R ⁴ , and R ⁷ is preferably an alkyl group having 4 to 18 carbon atoms, and the ester group that the organic groups of R ⁵ , R ⁶ , R ⁸ , R ^9, and R ¹⁰ have. Is preferably an ester group having 4 to 24 carbon atoms.

Specific examples of the organic tin compound represented by the general formula (2) include (C ₄ H ₉ ) ₂ Sn (OCOCH═CHCOOC ₈ H ₁₇ ) ₂ , (C ₄ H ₉ ) ₂ Sn (OCOCH═CHCOOC ₁₂ H). _{25) 2, (C 8 H} 17) 2 Sn (OCOC 8 H 17) 2, (C 8 H 17) 2 Sn (OCOC 11 H 23) 2, (C 8 H 17) 2 Sn (OCOCH = CHCOOC 4 H _{9) 2, (C 8 H} 17) 2 Sn (OCOCH = CHCOOC 8 H 17) 2, (C 8 H 17) 2 Sn (OCOCH = CHCOOC 13 H 27) 2, (C 8 H 17) 2 Sn (OCOCH = CHCOOC ₁₆ H ₃₃ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (OCOCH═CHCOOC ₁₇ H ₃₅ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (OCOCH═CHCOOC ₁₈ H ₃₇ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (OCOCH = CHCOOC ₂₀ H ₄₁ ) ₂ carboxylic acid type Organotin compounds;

_{(C 4 H 9) 2 Sn} (SCH 2 COOC 8 H 17) 2, (C 4 H 9) 2 Sn (SCH 2 CH 2 COOC 8 H 17) 2, (C 8 H 17) 2 Sn (SCH 2 COOC _{8 H 17) 2, (C} 8 H 17) 2 Sn (SCH 2 CH 2 COOC 8 H 17) 2, (C 8 H 17) 2 Sn (SCH 2 COOC 12 H 25) 2, (C 8 H 17) ₂ Sn (SCH ₂ CH ₂ COOC ₁₂ H ₂₅ ) ₂ , (C ₄ H ₉ ) ₂ Sn (SCOC ₈ H ₁₇ ) ₂ , (C ₄ H ₉ ) ₂ Sn (SCOC ₁₁ H ₂₃ ) ₂ , (C ₄ H ₉ ) ₂ Sn (SCOCH = CHCOOC ₈ H ₁₇ ) ₂ , (C ₄ H ₉ ) ₂ Sn (SCOCH = CHCOOC ₁₂ H ₂₅ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (SCOC ₈ H ₁₇ ) ₂ , (C _{8 H 17) 2 Sn (SCOC} 11 H 23) 2, (C 8 H 17) 2 Sn (SCOCH = CHCOOC 4 H 9) 2, (C 8 H 17) 2 S n (SCOCH = CHCOOC ₈ H ₁₇ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (SCOCH = CHCOOC ₁₃ H ₂₇ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (SCOCH = CHCOOC ₁₆ H ₃₃ ) ₂ , (C _{8 H 17) 2 Sn (SCOCH =} CHCOOC 17 H 35) 2, (C 8 H 17) 2 Sn (SCOCH = CHCOOC 18 H 37) 2, (C 8 H 17) 2 Sn (SCOCH = CHCOOC 20 H 41) 2 And mercaptide-type organic tin compounds.

Specific examples of the organic tin compound represented by the general formula (3) include (C ₄ H ₉ ) Sn (OCOC ₈ H ₁₇ ) ₃ , (C ₄ H ₉ ) Sn (OCOC ₁₁ H ₂₃ ) ₃ , _{(C 4 H 9) Sn (} OCOCH = CHCOOC 8 H 17) 3, (C 4 H 9) Sn (OCOCH = CHCOOC 12 H 25) 3, (C 8 H 17) Sn (OCOC 8 H 17) 3, ( _{C 8 H 17) Sn (OCOC} 11 H 23) 3, (C 8 H 17) Sn (OCOCH = CHCOOC 4 H 9) 3, (C 8 H 17) Sn (OCOCH = CHCOOC 8 H 17) 3, (C _{8 H 17) Sn (OCOCH =} CHCOOC 13 H 27) 3, (C 8 H 17) Sn (OCOCH = CHCOOC 16 H 33) 3, (C 8 H 17) Sn (OCOCH = CHCOOC 17 H 35) 3, ( _{C 8 H 17) Sn (OCOCH} = CHCOOC 18 H 37) 3, (C 8 _{17) Sn (OCOCH = CHCOOC 20} H 41) carboxylic acid type organic tin compounds such as _3;

_{(C 4 H 9) Sn (} SCH 2 COOC 8 H 17) 3, (C 4 H 9) Sn (SCH 2 CH 2 COOC 8 H 17) 3, (C 8 H 17) Sn (SCH 2 COOC 8 H 17 ) ₃ , (C ₈ H ₁₇ ) Sn (SCH ₂ CH ₂ COOC ₈ H ₁₇ ) ₃ , (C ₈ H ₁₇ ) Sn (SCH ₂ COOC ₁₂ H ₂₅ ) ₃ , (C ₈ H ₁₇ ) Sn (SCH ₂ CH ₂ COOC ₁₂ H ₂₅ ) ₃ ,

(C ₄ H ₉ ) Sn (SCOC ₈ H ₁₇ ) ₃ , (C ₄ H ₉ ) Sn (SCOC ₁₁ H ₂₃ ) ₃ , (C ₄ H ₉ ) Sn (SCOCH = CHCOOC ₈ H ₁₇ ) ₃ , (C _{4 H 9) Sn (SCOCH = CHCOOC} 12 H 25) 3, (C 8 H 17) Sn (SCOC 8 H 17) 3, (C 8 H 17) Sn (SCOC 11 H 23) 3, (C 8 H 17) Sn (SCOCH = CHCOOC ₄ H ₉ ) ₃ , (C ₈ H ₁₇ ) Sn (SCOCH = CHCOOC ₈ H ₁₇ ) ₃ , (C ₈ H ₁₇ ) Sn (SCOCH = CHCOOC ₁₃ H ₂₇ ) ₃ , (C ₈ H ₁₇ ) Sn (SCOCH = CHCOOC ₁₆ H ₃₃ ) ₃ , (C ₈ H ₁₇ ) Sn (SCOCH = CHCOOC ₁₇ H ₃₅ ) ₃ , (C ₈ H ₁₇ ) Sn (SCOCH = CHCOOC ₁₈ H ₃₇ ) ₃ , (C ₈ H ₁₇ ) Mercaps such as Sn (SCOCH = CHCOOC ₂₀ H ₄₁ ) ₃ Examples thereof include a tide type organotin compound.

Among these organic tin compounds, (C ₈ H ₁₇ ) ₂ Sn (OCOCH═CHCOOC ₈ H ₁₇ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (OCOCH═CHCOOC ₁₃ H ₂₇ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (OCOCH = CHCOOC ₁₆ H ₃₃ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (OCOCH = CHCOOC ₁₇ H ₃₅ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (OCOCH = CHCOOC ₁₈ H ₃₇ ) ₂ etc. preferable. In the 2nd aqueous dispersion, D component can be used individually or in mixture of 2 or more types.

  As the emulsifier in the second aqueous dispersion, the same emulsifier as used in preparing the first aqueous dispersion described above can be used. Among these, anionic surfactants such as sodium dodecylbenzenesulfonate and nonionic surfactants such as polyoxyethylene lauryl ether (for example, trade name: Emulgen 147, manufactured by Kao Corporation) can be suitably used.

  An emulsifier can be used individually or in mixture of 2 or more types. The usage-amount of an emulsifier is 1-100 mass parts normally with respect to 100 mass parts of D components, Preferably it is 5-80 mass parts, More preferably, it is 10-70 mass parts. If the amount used is less than 1 part by mass, the storage stability of the aqueous dispersion may be reduced. On the other hand, if it exceeds 100 parts by mass, the water resistance of the coating film may be lowered.

  The second aqueous dispersion can be prepared, for example, by the following method. First, D component and water are stirred and mixed. Next, an emulsifier is added to the mixed solution, and after stirring and mixing (preliminary dispersion), an ultrasonic homogenizer (for example, trade name: Ultrasonic Generator ET-30S-7, manufactured by Shimada Rika Kogyo Co., Ltd.) is used. Further dispersion is performed to obtain a second aqueous dispersion.

  The usage-amount of water is 100-2000 mass parts normally with respect to 100 mass parts of D components, Preferably it is 500-1500 mass parts, More preferably, it is 700-1200 mass parts. If the amount used is less than 10 parts by mass, the emulsion stability of the aqueous dispersion may be insufficient. On the other hand, when it exceeds 200 mass parts, the storage stability of an aqueous dispersion may fall. Further, the particle diameter of the dispersion by the ultrasonic homogenizer is usually 0.05 to 10 μm, preferably 0.1 to 1 μm.

  In the first aqueous dispersion described above or the second aqueous dispersion (hereinafter referred to as “aqueous dispersion of the present invention”), depending on the properties required for the coating film, Sol or colloidal inorganic compounds can be added. These average particle diameters are usually about 0.01 to 1000 μm in the case of powder, and are usually about 0.001 to 100 μm in the case of sol or colloid.

Examples of inorganic compounds that can be used as the filler include SiO ₂ , Al ₂ O ₃ , AlGa, and the like, in addition to semiconductors having photocatalytic activity such as TiO ₃ , SrTiO ₃ , and FeTiO ₃ . These inorganic compounds can be used alone or in admixture of two or more. The addition amount of the inorganic compound is usually 500 parts by mass or less, preferably 400 parts by mass or less, in terms of solid content with respect to 100 parts by mass of the total mass of the component A and the component B. These inorganic compounds may be added during the preparation of the aqueous dispersion, or may be added after the preparation of the aqueous dispersion.

  In addition, a filler other than the above-described inorganic compound can be added to the aqueous dispersion of the present invention separately for coloring, thickening, and the like of the resulting coating film. Examples of the filler include water-insoluble organic pigments and inorganic pigments; particulate, fibrous or scale-like ceramics other than pigments; metals, alloys, metal oxides, metal hydroxides, metal carbides, metal nitrides And metal sulfides. These fillers can be used alone or in admixture of two or more. The addition amount of the filler is usually 300 parts by mass or less with respect to 100 parts by mass of the total mass of the A component and the B component.

  Furthermore, a film-forming aid can be added to the aqueous dispersion of the present invention in order to promote the formation of a coating film. Examples of such film-forming aids include alcohols having a boiling point of 100 ° C. or higher such as n-hexyl alcohol; cellosolves such as methyl cellosolve; carbitols such as methyl carbitol; cellosolve acetates such as methyl cellosolve acetate. Carbitol acetates such as butyl carbitol acetate; phosphates such as tri-n-butoxymethyl phosphate;

  These film-forming aids can be used alone or in admixture of two or more. The amount of the film-forming aid added is usually 20% by mass or less, preferably 10% by mass or less, and more preferably 5% by mass or less with respect to 100 parts by mass of the total mass of the two aqueous dispersions. The film-forming aid may be added at the time of preparing the aqueous dispersion, may be added at the stage of forming the coating film, or at the time of preparing the aqueous dispersion and at the time of forming the coating film. You may add by both.

  Furthermore, a leveling agent can be added to the aqueous dispersion of the present invention in order to further improve the coating property. By adding a leveling agent, the finished appearance of the coating film is further improved, and it can be applied uniformly as a thin film.

  As such a leveling agent, a fluorine-based leveling agent (for example, trade name: BM1000, manufactured by BM-CHEMIE), a silicone-based leveling agent (for example, trade name: BYK series, manufactured by Big Chemie), Examples include ether-based or ester-based leveling agents (for example, trade name: Carfinol, manufactured by Nissin Chemical Industry Co., Ltd.).

  These leveling agents can be used alone or in admixture of two or more. The addition amount of the leveling agent is usually 5 parts by mass or less, preferably 3 parts by mass or less with respect to 100 parts by mass of the total solid content of the aqueous dispersion. The leveling agent may be added when preparing the aqueous dispersion, may be added at the stage of forming the coating film, or both when preparing the aqueous dispersion and when forming the coating film. It may be added.

  The aqueous dispersion of the present invention may contain, as desired, dispersants such as polyoxyethylene alkyl ether; celluloses such as methylcellulose; thickeners such as castor oil derivatives; inorganic foaming agents such as ammonium carbonate; azobisisobuty In addition to organic foaming agents such as azo compounds such as ronitrile, other additives such as titanium coupling agents and dyes can also be added.

  The total solid content concentration of the aqueous dispersion of the present invention is usually 10 to 55% by mass, preferably 15 to 50% by mass, and is appropriately adjusted according to the purpose of use. In addition, when the total solid content concentration exceeds 55% by mass, the leveling property tends to be lowered.

  The aqueous antifouling paint of the present invention is a two-component mixed antifouling paint composed of the first aqueous dispersion and the second aqueous dispersion described above. That is, when the first aqueous dispersion and the second aqueous dispersion are mixed, the D component in the second aqueous dispersion: the organotin compound causes the A component in the first aqueous dispersion: organo The reaction of cross-linking siloxane with each other, hydrolysis reaction of ester part, or condensation reaction with C component: nonionic water-soluble polymer and the like are promoted, and performance as an antifouling paint is exhibited. However, depending on the reactivity of the D component in the second aqueous dispersion, the storage stability may be relatively high, and the first aqueous dispersion and the second aqueous dispersion were previously mixed. It can also be used as a one-component water-based antifouling paint.

  In the water-based antifouling paint of the present invention, the D component is 0.01 to 10 parts by mass, preferably 0.1 to 5 parts by mass, and more preferably 0 with respect to 100 parts by mass of the total mass of the A and B components. The first aqueous dispersion and the second aqueous dispersion are mixed so as to be 5 to 3 parts by mass. If the amount of component D used is less than 0.01 parts by mass, the stain resistance may not be sufficiently improved. On the other hand, if it exceeds 10 parts by mass, the storage stability of the aqueous dispersion may decrease.

  The water-based antifouling paint of the present invention can be used alone or mixed with other resins or resin emulsions, and can be used for top coating and undercoating.

  As an embodiment of the water-based antifouling paint of the present invention, for example, a water-based antifouling paint is produced by mixing a first water-based dispersion and a second water-based dispersion, and the water-based antifouling paint is used as a base material. After applying the first aqueous dispersion to the surface of the base material to form a coating layer in addition to the aspect of obtaining a coated body having an antifouling coating film formed on the surface of the base material by applying to the surface of Further, an aspect of producing a water-based antifouling paint by applying or spraying the second aqueous dispersion on the surface of the coating layer to obtain a coated body having an antifouling coating film formed on the surface of the substrate, etc. Can be mentioned.

  And as a particularly preferable application target of the water-based antifouling paint of the present invention, there are building materials that are required to have excellent stain resistance, particularly building materials for outer walls. In such an application, a building material equipped with an antifouling coating film formed by an aqueous antifouling paint produced from the first aqueous dispersion and the second aqueous dispersion is preferably used. Can be used.

  Examples of the substrate to which the water-based antifouling paint of the present invention can be applied include, for example, polyester resins, polyamide resins, polyolefins, poly (meth) acrylate resins, fluorine resins, AN resins, ABS resins, MBS resins, AES resins, In addition to plastic base materials such as polychlorinated biphenyl, polyvinyl alcohol, polycarbonate, polyurethane, and polyimide, organic base materials such as wood and paper; metal base materials such as iron, aluminum, and stainless steel; cement, concrete, ALC, flexible boards, Examples thereof include inorganic ceramic base materials such as mortar, slate, gypsum, ceramics, and bricks.

  For these substrates, for example, blasting, chemical treatment, degreasing, flame treatment, oxidation treatment, steam treatment, for the purpose of adjusting the base, improving adhesion, sealing the porous substrate, smoothing, patterning, etc. Further, a ground treatment such as a corona discharge treatment, an ultraviolet irradiation treatment, a plasma treatment, or an ion treatment may be performed.

  For coating the substrate with the water-based antifouling paint of the present invention, coating means such as brush, roll coater, flow coater, centrifugal coater, ultrasonic coater, (micro) gravure coater, dip coating, flow coating, spray coating, A coating method such as a screen process or electrodeposition coating can be employed.

  The coating thickness of the water-based antifouling paint of the present invention is usually about 0.05 to 200 μm as a dry film thickness. Thereafter, the coating film can be formed by drying at room temperature or by heating for about 1 to 60 minutes at a temperature of about 30 to 200 ° C. for drying.

  In addition, the coating thickness in the case of applying the undercoat using the water-based antifouling paint of the present invention or other paints is about 0.05 to 20 μm by one application as a dry film thickness, and 0.1 to 2 by two application. It is about 40 μm. Thereafter, the undercoat layer can be formed by drying at room temperature or by heating for about 1 to 60 minutes at a temperature of about 30 to 200 ° C. for drying. The total film thickness of the undercoat layer and the topcoat layer of the coated body using the water-based antifouling paint of the present invention is a dry film thickness, usually about 0.1 to 400 μm, preferably about 0.2 to 300 μm.

  The coating specifications with the water-based antifouling paint of the present invention vary depending on the type and state of the substrate, the purpose of coating, the coating method, etc., ensuring adhesion between the substrate and the coating film, preventing rust, preventing erosion, preventing moisture intrusion, etc. For this purpose, an undercoat layer is provided. Examples of the material used for the undercoat layer include a primer not containing a filler and a sealer containing a filler used for the purpose of imparting the design of the appearance of the coating film in addition to the above-described purpose. The kind of primer and sealer is not particularly limited, and can be appropriately selected according to the kind of substrate, purpose of use, and the like.

  In the case of a metal substrate, an undercoat layer such as a primer or sealer is provided if rust prevention is required. In the case of an inorganic ceramic base, the primer or sealer is usually used because the coating concealability varies depending on the properties (surface roughness, impregnation, alkalinity, etc.) of the base. In the case of an organic resin base material, a primer or a sealer is usually used. In the case of recoating a deteriorated coating film, a primer or sealer is used when the old coating film is significantly deteriorated. In the case of other base materials, such as metals that do not require rust prevention, tiles, glass, etc., an undercoat layer may or may not be provided depending on the application.

  Examples of materials used for the undercoat layer include alkyd resins, amino alkyd resins, epoxy resins, polyesters, acrylic resins, urethane resins, fluororesins, acrylic silicone resins, acrylic emulsions, epoxy emulsions, polyurethane emulsions, polyester emulsions, acrylic urethanes. Examples thereof include emulsions, silicone-containing emulsions such as acrylic silicone emulsions and polysiloxanes. These materials can be used alone or in admixture of two or more, and can also be used in admixture with the aqueous dispersion of the present invention.

  As a preferable combination of materials for the undercoat layer when using the water-based antifouling paint of the present invention, for example, acrylic emulsion / water-based dispersion of the present invention, acrylic emulsion / epoxy emulsion, silicone-containing emulsion / epoxy emulsion, epoxy emulsion / Acrylic urethane emulsion, acrylic silicone emulsion / epoxy emulsion / acrylic emulsion and the like can be mentioned.

As a typical structure of the coated body coated with the water-based antifouling paint of the present invention, for example, the following can be mentioned.
(A): Substrate (with or without primer treatment) / clear or enamel of the water-based antifouling paint of the present invention.
(B) Substrate (with or without primer treatment) / enamel (undercoat layer) of the water-based antifouling paint of the present invention / clear (topcoat layer) of the water-based antifouling paint of the present invention.
(C) Base material (with or without primer treatment) / clear or enamel of other resin (undercoat layer) / clear or enamel of the water-based antifouling paint of the present invention (overcoat layer).

  Hereinafter, the embodiment of the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples.

[Measurement / Evaluation]
About the water-system antifouling paint of an Example and a comparative example, the following test was evaluated and the hydrophilic property, the antifouling property improvement effect, the effect sustainability, and the storage stability were evaluated.

(Hydrophilic)
About the test piece which apply | coated the water-system antifouling paint of the Example and the comparative example, the hydrophilic property of the coating-film surface was evaluated by measuring the water contact angle of the coating-film surface. Specifically, the evaluation was performed by the following method. First, a white enamel (pigment concentration: 40%) with a silicone acrylic emulsion (trade name: B7302, manufactured by JSR) as a varnish was applied as a subbing layer to a hard aluminum plate serving as a substrate at a dry weight of 50 g / m ² dry. Then, as an overcoat layer, the water-based antifouling paints of Examples or Comparative Examples were applied at a dry weight of 25 g / m ² dry using a spray gun, and heated at 140 ° C. for 4 minutes using a gear oven, whereby the substrate surface A test piece having a coating film formed thereon was prepared. Next, this test piece was placed on a north surface vertical exposure stand installed in the Yokkaichi factory of JSR Corporation, and left for one month. Thereafter, the water contact angle on the surface of the test piece was measured with an automatic contact angle meter (trade name: CA-V150, manufactured by Kyowa Interface Science Co., Ltd.), and hydrophilicity was evaluated according to the following criteria.
○: Water contact angle is 65 ° or less (good)
Δ: Water contact angle is over 65 ° and 75 ° or less (slightly poor)
×: Water contact angle exceeds 75 ° (defect)

(Contamination resistance improvement effect)
For the test pieces coated with the water-based antifouling paints of Examples and Comparative Examples, the surface of the paint film was forcibly contaminated, and the paint film surface after washing it off was visually observed, whereby the resistance of the water-based antifouling paint was confirmed. Contamination improvement effect was evaluated. Specifically, the evaluation was performed by the following method. First, after immersing a test piece similar to that prepared for the above-described evaluation of the hydrophilization effect in a carbon slurry liquid (trade name: EP-510 Black, manufactured by Dainichi Seika Co., Ltd.), it is immediately taken out, and a gear oven is used. And heated at 140 ° C. for 4 minutes. Next, this was cooled to room temperature, washed with water while gently rubbing the surface of the coating film with a dishwashing sponge, and the carbon slurry was washed away. Thereafter, the surface of the test piece was visually observed, and the contamination resistance improving effect was evaluated according to the following criteria.
○: The whiteness before evaluation is maintained as a whole (good)
Δ: Overall blackened from the whiteness before evaluation (slightly poor)
X: Carbon stains remain and are blackened as a whole (defect)

(Effective durability)
For the test pieces coated with the water-based antifouling paints of Examples and Comparative Examples, the water-based antifouling paints were exposed to the outdoors for several months to contaminate the paint film surface and visually observe the paint film surface. The sustainability of the effect was evaluated. Specifically, the evaluation was performed by the following method. First, a test piece similar to that prepared for evaluating the hydrophilization effect was placed on a north surface vertical exposure table installed in the Yokkaichi factory of JSR Corporation, and left for 8 months. Thereafter, the surface of the test piece was visually observed, and the effect persistence was evaluated according to the following criteria.
○: Rain stripes are not conspicuous and the whole is white before exposure (good)
△: Rain lines are inconspicuous, but the whole is blackened from the whiteness before exposure (somewhat poor)
×: Rain lines are conspicuous (defect)

(Storage stability)
About the water-system antifouling paint of an Example and a comparative example, after leaving it for a certain period on severe conditions, the storage stability of the water-system antifouling paint was evaluated by observing the aspect of a water-system antifouling paint visually. Specifically, the evaluation was performed by the following method. First, the water-based antifouling paints of Examples and Comparative Examples were put in plastic bottles, sealed, and left at 50 ° C. for one month. Thereafter, the state of the water-based antifouling paint was visually evaluated, and the storage stability was evaluated according to the following criteria.
○: none of solidification, formation of aggregates, and increase in viscosity are observed (good)
Δ: Solidification and formation of agglomerates are not observed, but an apparent increase in viscosity is observed (somewhat poor)
X: Solidification and formation of aggregates are observed (poor)

  In addition, as a “tetraethoxysilane condensate” in the table, a tetraethoxysilane decamer (trade name: ethyl silicate 48, manufactured by Colcoat Co.) is used, and as a “methyltrimethoxysilane condensate”, methyltrimethoxy is used. Silane 10-15 mer (trade name: X40-9220, manufactured by Shin-Etsu Chemical Co., Ltd.), “sodium dodecylbenzenesulfonate”, manufactured by Kao Corporation, “polyoxyethylene lauryl ether” Emulgen 147 (trade name) manufactured by Kao Corporation was used.

  In the table, “polyethylene glycol (I)” is polyethylene glycol having a weight average molecular weight of 30,000, “polyethylene glycol (II)” is polyethylene glycol having a weight average molecular weight of 5,000, and “polyethylene glycol (III) ) "Is polyethylene glycol having a weight average molecular weight of 1,000," organic tin compound (I) "is di-n-butyltin dilaurate, and" organotin compound (II) "is dioctyltin dimaleate alkyl. An ester salt (the alkyl group has 13 carbon atoms) was used, and butyltin nonanoate was used as the “organotin compound (III)”.

[Example 1]
(1) 1st aqueous dispersion First, as shown in Table 1, A component: 20 mass parts of tetraethoxysilane condensate, B'-1 component: 10 mass parts of methyl methacrylate, 9 mass parts of cyclohexyl methacrylate, 2- 1 part by mass of hydroxyethyl methacrylate, 9 parts by mass of n-butyl acrylate, 1 part by mass of γ-methacryloxytrimethoxysilane, emulsifier: 1.0 part by mass of anionic surfactant sodium dodecylbenzenesulfonate, nonionic interfacial agent 0.5 mass part of a certain polyoxyethylene lauryl ether and 120 mass parts of water were stirred for 10 minutes at room temperature to emulsify.

  Next, the above emulsion was refined with a high-pressure homogenizer under a pressure of 70 MPa so that the average particle size was 0.5 μm or less. The pH at this time was 6.5. The fact that the average particle size of the emulsion was refined to 0.5 μm or less was confirmed by a particle size measuring device FPAR-1000 (trade name) manufactured by Otsuka Electronics Co., Ltd. As the “high pressure homogenizer”, a microfluidizer M110Y (trade name) manufactured by Mizuho Industry Co., Ltd. was used.

  Thereafter, the above emulsion was put into a four-necked separable flask and purged with nitrogen while stirring. Then, with respect to 100 parts by mass of the total mass of the component A and the component B ′, azobisiso is used as a radical polymerization initiator. 3 parts by weight of butyronitrile was added, and polymerization was carried out at 75 ° C. for 2 hours.

  Further, while maintaining the reaction temperature at 75 ° C., as shown in Table 1, B′-2 component: 15 parts by mass of methyl methacrylate, 19 parts by mass of n-butyl acrylate, 8 parts by mass of cyclohexyl methacrylate, 2-hydroxyethyl methacrylate 1 part by mass, 5 parts by mass of diacetone acrylamide, 1 part by mass of γ-methacryloxytrimethoxysilane, 1 part by mass of ethylene glycol dimethacrylate, emulsifier: 0.6 part by mass of sodium dodecylbenzenesulfonate which is an anionic surfactant, A nonionic interfacial polyoxyethylene lauryl ether 0.5 part by mass and water 70 parts by mass pre-emulsified with a stirrer were added dropwise over 2 hours.

  After completion of the dropping, the reaction temperature was raised to 85 ° C., and polymerization was further performed for 1 hour to form a B component (acrylic polymer) to obtain an aqueous dispersion containing the A component and the B component. The solid concentration at this time was about 35%. The B component obtained here was a core-shell type polymer particle. To this aqueous dispersion, 5 parts by mass of component C: polyethylene glycol (reagent, molecular weight 30,000) shown in Table 1 at the ratio shown in Table 1 was added and stirred to obtain a first aqueous dispersion. .

(2) Second aqueous dispersion First, water was added to component D: di-n-butyltin dilaurate (organotin compound) shown in Table 1, and these were mixed by stirring at room temperature for 10 minutes. At this time, water was added so that the mass ratio of the D component and water was 1: 9.

  Next, an anionic surfactant sodium dodecylbenzenesulfonate and a nonionic surfactant polyoxyethylene lauryl ether were added to the mixture as an emulsifier, and the mixture was stirred and mixed (preliminary dispersion). At this time, the amount ratio of each component was 5 parts by mass of sodium dodecylbenzenesulfonate and 2 parts by mass of polyoxyethylene lauryl ether with respect to 100 parts by mass of the total mass of component D and water.

  Further, the mixture (preliminary dispersion) was dispersed using an ultrasonic homogenizer to obtain a second aqueous dispersion. The solid concentration at this time was about 15%. As the “ultrasonic homogenizer”, Ultrasonic Generator ET-30S-7 (trade name) manufactured by Shimada Rika Kogyo Co., Ltd. was used.

(3) Water-based antifouling paint The first dispersion and the second dispersion prepared as described above were mixed with a 10% aqueous solution of D component di-n-butyltin dilaurate, and A component and B component. The 1st aqueous dispersion and the 2nd aqueous dispersion were mixed so that it might be 5 mass parts in conversion of solid content with respect to 100 mass parts of total mass. Further, adipic acid dihydrazide as a crosslinking agent and a 50% aqueous solution of ethylene glycol monobutyl ether as a film forming aid were added to and mixed with the mixed solution to obtain an aqueous antifouling paint. In this case, the amount ratio of each component was 2 parts by mass of adipic acid dihydrazide and 5 parts by mass of ethylene glycol monobutyl ether in terms of solid content with respect to 100 parts by mass of the total mass of component A and component B. Various evaluations were made on these water-based antifouling paints. The results are shown in Table 1.

[Examples 2-7, Comparative Examples 1-6]
(1) First aqueous dispersion First, dodecylbenzenesulfone which is an anionic surfactant as an emulsifier for the A component (organosiloxane) and B′-1 component (constituent monomer) shown in Tables 1 and 2. Sodium acid, nonionic surfactant polyoxyethylene lauryl ether and water were added, and the mixture was stirred at room temperature for 10 minutes to emulsify. At this time, the amount ratio of each component is 100 parts by mass with respect to the total mass of the A component and the B ′ component (including both “B′-1 component” and “B′-2 component” in the table). 1.0 parts by mass of sodium dodecylbenzenesulfonate, 0.5 parts by mass of polyoxyethylene lauryl ether, and 120 parts by mass of water.

  Next, the above emulsion was refined with a high-pressure homogenizer under a pressure of 70 MPa so that the average particle size was 0.5 μm or less. At this time, the fact that the average particle size of the emulsion was refined to 0.5 μm or less was confirmed by a particle size measuring device FPAR-1000 (trade name) manufactured by Otsuka Electronics Co., Ltd. As the “high pressure homogenizer”, a microfluidizer M110Y (trade name) manufactured by Mizuho Industry Co., Ltd. was used.

  Thereafter, the above emulsion was put into a four-necked separable flask and purged with nitrogen while stirring, and then azobis as a radical polymerization initiator with respect to a total mass of 100 parts by mass of the A component and the B ′ component. 3 parts by mass of isobutyronitrile was added and polymerized at 75 ° C. for 2 hours.

  Furthermore, while maintaining the reaction temperature at 75 ° C., B′-2 components having the compositions shown in Tables 1 and 2, an anionic surfactant sodium dodecylbenzenesulfonate (manufactured by Kao Corporation), and water as emulsifiers were added. What was previously emulsified with a stirrer was added dropwise over 2 hours. After completion of the dropwise addition, the reaction temperature was raised to 85 ° C., and further polymerized for 1 hour to form a B component (acrylic polymer) to obtain an aqueous dispersion containing the A component and the B component. The B component obtained here is a core-shell type polymer particle. C components (nonionic water-soluble polymers) shown in Tables 1 and 2 were added to the aqueous dispersions at the ratios shown in Tables 1 and 2, and mixed to obtain a first aqueous dispersion.

[Comparative Example 7]
Instead of the core / shell polymer, an acrylic emulsion polymer (trade name: B7302, manufactured by JSR, glass transition point 35 ° C. (calculated value)) is used as the B-component acrylic polymer. By mixing with component C, a first aqueous dispersion having the composition described in Table 2 was obtained.

(2) Second Aqueous Dispersion First, water was added to component D (organotin compound) shown in Tables 1 and 2, and these were mixed by stirring at room temperature for 10 minutes. At this time, water was added so that the mass ratio of the D component and water was 1: 9.

  Next, an anionic surfactant sodium dodecylbenzenesulfonate and a nonionic surfactant polyoxyethylene lauryl ether were added to the mixture as an emulsifier, and the mixture was stirred and mixed (preliminary dispersion). At this time, the amount ratio of each component was 5 parts by mass of sodium dodecylbenzenesulfonate and 2 parts by mass of polyoxyethylene lauryl ether with respect to 100 parts by mass of the total mass of component D and water.

  Furthermore, this mixed liquid (preliminary dispersion) was dispersed using an ultrasonic homogenizer to obtain a second aqueous dispersion having a solid content concentration of about 15%. As the “ultrasonic homogenizer”, Ultrasonic Generator ET-30S-7 (trade name) manufactured by Shimada Rika Kogyo Co., Ltd. was used.

(3) Water-based antifouling paint The first dispersion and the second dispersion prepared as described above are prepared as follows. D component (solid content concentration, about 15%) is a total mass of A component and B component of 100. The 1st aqueous dispersion and the 2nd aqueous dispersion were mixed so that it might become 0.01-10 mass parts in conversion of solid content with respect to mass parts. Furthermore, a 50% aqueous solution of adipic acid dihydrazide as a crosslinking agent and 50% aqueous solution of ethylene glycol monobutyl ether as a film forming aid was added to and mixed with this mixed solution to obtain an aqueous antifouling paint. In this case, the amount ratio of each component was 2 parts by mass of adipic acid dihydrazide and 5 parts by mass of ethylene glycol monobutyl ether in terms of solid content with respect to 100 parts by mass of the total mass of component A and component B. Various evaluations were made on these water-based antifouling paints. The results are shown in Tables 1 and 2.

(Evaluation results)
The water-based antifouling paints of Examples 1 to 7 showed good results in all items of hydrophilicity, antifouling improvement effect, effect persistence, and storage stability. That is, the water-based antifouling paints of Examples 1 to 7 were able to exhibit a higher antifouling effect from the beginning of the coating and to maintain the antifouling effect for a long time.

  On the other hand, the water-based antifouling paints of Comparative Examples 1 to 7 showed unsatisfactory results in any of the items of hydrophilicity, antifouling improvement effect, effect persistence, and storage stability. Specifically, the water-based antifouling paint of Comparative Example 1 was slightly poor in storage stability. This was considered due to the fact that the amount of component A used exceeded 50% by mass with respect to the total mass of component A and component B. The water-based antifouling paint of Comparative Example 2 had poor hydrophilicity, and the effect of improving antifouling properties was somewhat poor. This was considered due to the fact that the amount of component A used was less than 2% by mass with respect to the total mass of component A and component B. The water-based antifouling paint of Comparative Example 3 was poor in both hydrophilicity and antifouling effect. This was considered due to the fact that the amount of component C used was less than 0.1 parts by mass relative to 100 parts by mass of the total mass of component A and component B.

  Further, the water-based antifouling paint of Comparative Example 4 was somewhat poor in storage stability. This was thought to be due to the amount of component C used exceeding 20 parts by mass with respect to 100 parts by mass of the total mass of component A and component B. The water-based antifouling paint of Comparative Example 5 had a slightly poor antifouling effect. This was considered due to the fact that the amount of component D used was less than 0.01 parts by mass relative to the total mass of component A and component B. The water-based antifouling paint of Comparative Example 6 had poor storage stability. This was considered to be because the amount of C component used exceeded 10 parts by mass with respect to 100 parts by mass of the total mass of the A and B components. The water-based antifouling paint of Comparative Example 7 had poor storage stability. This was considered due to the fact that the acrylic polymer of component B did not form core-shell particles.

  The antifouling paint of the present invention is suitably used as a water-based antifouling paint capable of forming a coating film excellent in stain resistance.

Claims (7)

In an aqueous medium, polyorganosiloxane (A component) which is at least one condensate selected from organosilane (A ′ component) represented by the following general formula (1), and a glass transition point of −20 ° C. to A + 80 ° C. acrylic polymer (component B), a nonionic water-soluble polymer and / or an anion group-containing water-soluble polymer (component C),
The A component is 2 to 50% by mass with respect to the total mass of the A component and the B component, the B component is 50 to 98% by mass with respect to the total mass of the A component and the B component, and the C An aqueous dispersion containing 0.1 to 20 parts by mass of a component with respect to 100 parts by mass of a total mass of the component A and the component B,
In an aqueous medium, after mixing and emulsifying the A component, a part of the monomer constituting the B component (B ′ component), and an emulsifier, the average particle size of the emulsion is refined to 0.5 μm or less. Then, in the presence of a radical polymerization initiator, at a pH of 4 to 9, radical polymerization is carried out by adding the remainder of the B ′ component to the reaction solution obtained by radical polymerization of a part of the B ′ component. After forming the said B component by this, the said C component is added, and the aqueous dispersion which is mixed.
(R ¹ ) _4-n Si (OR ² ) _n (1)
(In the formula, R ¹ represents a hydrogen atom or a monovalent organic group, R ² represents an alkyl group or an acyl group, and n is 3 or 4.) In an aqueous medium, polyorganosiloxane (A component) which is at least one condensate selected from organosilane (A ′ component) represented by the following general formula (1), and a glass transition point of −20 ° C. to A + 80 ° C. acrylic polymer (component B), a nonionic water-soluble polymer and / or an anion group-containing water-soluble polymer (component C),
The A component is 2 to 50% by mass with respect to the total mass of the A component and the B component, the B component is 50 to 98% by mass with respect to the total mass of the A component and the B component, and the C The component is a method for producing an aqueous dispersion containing 0.1 to 20 parts by mass with respect to 100 parts by mass of the total mass of the component A and the component B,
In an aqueous medium, after mixing and emulsifying the A component, a part of the monomer constituting the B component (B ′ component), and an emulsifier, the average particle size of the emulsion is refined to 0.5 μm or less. Then, in the presence of a radical polymerization initiator, at a pH of 4 to 9, radical polymerization is carried out by adding the remainder of the B ′ component to the reaction solution obtained by radical polymerization of a part of the B ′ component. After forming the said B component by this, the said C component is added and the manufacturing method of the aqueous dispersion which mixes.
(R ¹ ) _4-n Si (OR ² ) _n (1)
(In the formula, R ¹ represents a hydrogen atom or a monovalent organic group, R ² represents an alkyl group or an acyl group, and n is 3 or 4.) An aqueous dispersion containing an organic tin compound (component D) represented by the following general formula (2) or the following general formula (3) and having a molecular weight of 640 or more and an emulsifier in an aqueous medium.
(R ³ ) (R ⁴ ) Sn (R ⁵ ) (R ⁶ ) (2)
(R ⁷ ) Sn (R ⁸ ) (R ⁹ ) (R ¹⁰ ) (3)
(In the formula, R ³ , R ⁴ , and R ⁷ each represents an alkyl group, and R ⁵ , R ⁶ , R ⁸ , R ^9, and R ¹⁰ represent a monovalent organic group each having an ester group. Show.) It is comprised from the aqueous dispersion of Claim 1, and the aqueous dispersion of Claim 3.
The aqueous dispersion according to claim 1 and the aqueous system according to claim 3, wherein the D component is 0.01 to 10 parts by mass with respect to 100 parts by mass of the total mass of the A component and the B component. A two-component water-based antifouling paint that mixes with the dispersion.   The aqueous dispersion according to claim 1 and the aqueous dispersion according to claim 3 are mixed to produce an aqueous antifouling paint, and the aqueous antifouling paint is applied to the surface of a substrate, A method for producing a coated body, wherein a coated body having an antifouling coating film formed on the surface of a substrate is obtained.   The aqueous dispersion according to claim 1 is applied to the surface of a substrate to form a coating layer, and then the aqueous dispersion according to claim 3 is further applied or sprayed onto the surface of the coating layer. A method for producing a coated body, wherein an antifouling paint is produced to obtain a coated body having an antifouling coating film formed on the surface of the substrate.   A building material provided on its surface with an antifouling coating film formed from an aqueous antifouling paint produced from the aqueous dispersion according to claim 1 and the aqueous dispersion according to claim 3.