JP2003003030A - Aqueous dispersion - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an aqueous dispersion useful as an aqueous coating agent and excellent in the balance between weatherability and adhesiveness and in the balance between blocking resistance and frost damage resistance which are not obtainable by a conventional known method. SOLUTION: The aqueous dispersion is composed of a composite particle of a polyorganosiloxane/an acrylic polymer dispersed in an aqueous medium. The composite particle contains (A) 5-80 pts.wt. (based on a complete hydrolyzed condensate) of a polyorganosiloxane composed of a hydrolyzed condensate of an organosilane represented by the formula; (R<1> )4-n -(Si)-(OR<2> )n (wherein, R<1> is identical or different, hydrogen, phenyl or a 1-8C monovalent organic group; R<2> is identical or different, hydrogen, a 1-5C alkyl or a 1-6C acyl; n is an integer of 2-4) and (B) 95-20 pts.wt. of an acrylic polymer having a glass transition temperature from -20 deg.C to 80 deg.C (wherein, (A)+(B) is equal to 100 pts.wt.). The pts.wt. x of the component (A) (based on a complete hydrolyzed condensate) and the n in the above general formula which constitutes the component (A) satisfy the following formula: (-0.005x+2.6)<=n<=(-0.005x+3.3).

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a water-based dispersion, and more specifically, a water-based coating excellent in weather resistance / adhesion balance and blocking resistance / freezing damage resistance balance, which have not been obtained by conventionally known methods. The present invention relates to an aqueous dispersion useful as an agent.

[0002]

2. Description of the Related Art Conventionally, water-based coating agents have been used in various fields against the backdrop of environmental problems, and the range of application thereof is steadily expanding.
The performance requirements for coating agents are also becoming more sophisticated. In recent years, weather resistance, adhesion, blocking resistance,
There is a demand for a low-cost coating agent that has excellent performance balance such as frost resistance. As a means for satisfying these demands, polyorganosilocysan composite polymer particles obtained by compositing polyorganosilocysan and an organic polymer component disclosed in JP-A-3-45628 have come to be widely used. However, generally, when the polyorganosiloxane component in the polyorganosilocysan composite polymer particles is increased, the weather resistance is improved, but the adhesion to the base material is decreased, and when the degree of crosslinking in the polyorganosiloxane is increased. However, there is a problem that although the blocking resistance is improved, the frost damage resistance is reduced.

Further, a method of compounding a sufficient amount of polyorganosilocysan in order to obtain sufficient weather resistance is disclosed, for example, in JP-A-10-183064.
There is a method of previously synthesizing a silanol group-containing silicone resin, removing a solvent, and then dissolving the resin in a radically polymerizable monomer to carry out emulsion polymerization. Further, there is a method disclosed in Japanese Patent Application Laid-Open No. 2000-53919, in which a condensate of tetraalkoxysilane is synthesized in advance, the solvent is removed, and then dissolved in a radically polymerizable monomer to carry out miniemulsion polymerization. However, these methods have the drawbacks that the synthesis cost of the organosilane, the removal of the solvent, the dissolution in the monomer, the radical polymerization and the polymerization production process are complicated, and the production cost is high. Further, a method of using a polyorganosiloxane having a radically polymerizable functional group, which is a so-called silicon macromonomer, has not been widely used because the silicon macromonomer is expensive.

[0004]

The present invention provides an aqueous dispersion useful as an aqueous coating agent, which is excellent in weather resistance / adhesiveness balance and blocking resistance / freezing damage resistance balance, which has not been obtained by a conventionally known method. The purpose is to get.

[0005]

According to the present invention, in an aqueous medium, (A) the following general formula (1) (R ¹ ) _4-n- (Si)-(OR ² ) _n (1) ( In the formula, R ¹ is the same or different, a hydrogen atom, a phenyl group or a monovalent organic group having 1 to 8 carbon atoms, and R ² is the same or different, a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a carbon number 1 An acyl group of 6 and n is an integer of 2 to 4.)
5 to 80 parts by weight of a polyorganosiloxane (calculated as a complete hydrolyzed condensate) obtained from at least one selected from the group consisting of organosilanes represented by: , And (B) 95 to 20 parts by weight of an acrylic polymer having a glass transition point of −20 ° C. to 80 ° C. [where (A) + (B) = 1
00 parts by weight], and n of the general formula (1) constituting the component (A) (completely hydrolyzed condensate) and the component (A) satisfies the following formula (2): The present invention relates to an aqueous dispersion in which polyorganosiloxane / acrylic polymer composite particles are dispersed. (−0.005x + 2.6) ≦ n ≦ (−0.005x + 3.3) (2) The aqueous dispersion of the present invention is represented by (A ′) general formula (1) in an aqueous medium. At least one selected from the group consisting of organosilane, its hydrolyzate and its condensate,
(B ') The radical polymerizable monomer component containing the acrylic monomer constituting the acrylic polymer (B) and the emulsifier (C) are mixed to form an emulsion, and the component (A') is hydrolyzed. After proceeding with decomposition and condensation, the average particle size of the emulsion is reduced to 0.5 μm or less, and then (D) a radical polymerization initiator is added to radically polymerize the monomer component (B ′) (hereinafter, “ Also referred to as "mini-emulsion polymerization"). The (B ′) monomer component includes a radical polymerizable monomer having a dialkylamide group, a radical polymerizable monomer having a dialkylamino group, and a radical polymerizable monomer having a polyoxyethylene group. Those containing at least one selected from the group are preferable. The (C) emulsifier preferably contains a reactive emulsifier having a polyoxyethylene chain. Further, in the above emulsification, a (E) substantially water-insoluble light stabilizer may be present. In addition, in the above emulsification, (F)
Polystyrene-equivalent weight average molecular weight of 1,000 to 1
There may be 10,000 poly (meth) acrylates present.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The water-based dispersion of the present invention contains a hydrolyzed condensate of an organosilane having a siloxane cross-linking degree within a limited range as a polyorganosiloxane and having a limited content depending on the siloxane cross-linking degree. By combining with an acrylic polymer, weather resistance / adhesion balance, blocking resistance /
It has the advantage of being excellent in frost damage resistance balance.

As a method for producing the same, a radical polymerizable monomer component containing an acrylic monomer as a main component (hereinafter also referred to as "radical polymerizable monomer") is hydrolyzed / condensed with an organosilane, By carrying out the miniemulsion polymerization in an aqueous medium in the presence of an emulsifier, the following advantages which cannot be obtained by the conventionally known method are obtained. (1) Since the hydrolysis / condensation reaction of the organosiloxane does not proceed during radical polymerization of the radical-polymerizable monomer, there is no change in the concentration of alcohol, which is a by-product of the hydrolysis reaction, during radical polymerization, or There is little change in the concentration of the hydrophobic organosiloxane due to the condensation reaction of the siloxane during the polymerization, and therefore, the reaction stability during the radical polymerization is good even when a relatively large amount of polyorganosiloxane is contained. (2) In the emulsion particles, the radical-polymerizable monomer is polymerized in the presence of the component (A), which is a siloxane component, so that the siloxane component is extremely finely dispersed in the acrylic polymer, or The acrylic polymer forms an interpenetrating network (IPN). As a result, even if a methyl-based silicone resin having poor mutual solubility is used as the siloxane component, a coating film having excellent transparency is formed, and the lack of properties of both resins is complemented. In particular, since a large amount of hardness, chemical resistance, and a silicone resin rich in weather resistance can be contained, the formed film has excellent film-forming properties and good properties such as scratch resistance, weather resistance, and chemical resistance.
It gives a uniform cured coating with good flexibility. (3) In the emulsion particles, the polymers coexist in a solvent-free state, so that the degree of freedom of the silanol groups having high condensation activity in the siloxane component is limited. as a result,
Condensation of silanol groups is suppressed and good storage stability is obtained. (4) Since the silanol group having a specific structure is contained in a certain amount or more in the siloxane component (silicone resin), the silanol group is restrained in a good state in the emulsion particles, while its high curing activity is preserved and relatively high. Excellent curability is ensured even at low temperatures. In addition, by containing a large amount of silanol groups having a specific structure such as dialkoxysilanes as the hydrolyzable silane compound, the number of linear structures increases, and the coating film can have contradictory properties such as flexibility and hardness. . (5) A light stabilizer which is difficult to dissolve in water, which cannot be introduced at the time of ordinary emulsion polymerization, can be introduced into the composite particles of the present invention by miniemulsion polymerization, and as a result, a coating having excellent weather resistance can be obtained. A film can be formed.

Further, it has been found that the following method is particularly effective for improving the weather resistance / adhesiveness balance and the blocking resistance / freezing damage resistance balance in the aqueous dispersion of the present invention. (1) Copolymerizing a radical-polymerizable monomer having a specific functional group as a radical-polymerizable monomer in the composite particle of the present invention, which is excellent in freezing damage resistance without lowering blocking resistance. A coated film can be formed. (2) When a miniemulsion polymerization of the present invention is used, a reactive emulsifier having a polyoxyethylene chain is partially or entirely used as an emulsifier to form a coating film excellent in frost resistance without lowering blocking resistance. Can be formed. (3) By coexisting a poly (meth) acrylate having a specific molecular weight during the mini-emulsion polymerization of the present invention, a coating film excellent in blocking resistance can be formed without lowering the frost damage resistance.

(A) Polyorganosiloxane (A) The polyorganosiloxane that constitutes the aqueous dispersion of the present invention is a hydrolysis / condensation product of the organosilane represented by the general formula (1). The organosilane (hereinafter also referred to as "organosilane (1)") in the component (A) that constitutes the aqueous dispersion of the present invention is generally represented by the following general formula (1). _{^{(R 1) 4-n -}} (Si) - (OR 2) n ·· ... (1) ( In the formula, R ¹ are identical or different, a hydrogen atom, a monovalent organic phenyl or C1-8 The groups and R ² are the same or different and each is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or an acyl group having 1 to 6 carbon atoms, and n is an integer of 2 to 4.)

In the hydrolyzate of the organosilane (1), it is not necessary that all OR ² groups in the above general formula (1) contained in the organosilane of 2 to 4 are hydrolyzed. Only one may be hydrolyzed, two or more may be hydrolyzed, or a mixture thereof. Further, the condensate of the organosilane (1) is one in which silanol groups of a hydrolyzate of organosilane are condensed to form a Si-O-Si bond, but in the present invention, all the silanol groups are condensed. However, it is a concept that also includes a mixture of a small amount of silanol groups, a mixture of those having different degrees of condensation, and the like.

In the general formula (1), R ¹ has 1 to ¹ carbon atoms.
Examples of the monovalent organic group of 8 include a methyl group, an ethyl group, an n-propyl group, an i-propyl group, an n-butyl group,
i-butyl group, sec-butyl group, t-butyl group, n-
Alkyl group such as hexyl group, n-heptyl group, n-octyl group, 2-ethylhexyl group; Acyl group such as acetyl group, propionyl group, butyryl group, valeryl group, benzoyl group, trioyl group, caproyl group; vinyl group,
Examples include allyl group, cyclohexyl group, phenyl group, epoxy group, glycidyl group, (meth) acryloxy group, ureido group, amide group, fluoroacetamide group, and isocyanate group, as well as substituted derivatives of these groups. it can.

The substituent in the substituted derivative of R ¹ is, for example, 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, (meth). An acryloxy group, a ureido group, an ammonium base etc. can be mentioned. However, the carbon number of R ¹ including these substituted derivatives is 8 or less including the carbon atoms in the substituent. When two R ¹ 's are present in the general formula (1), they may be the same or different.

Examples of the alkyl group having 1 to 5 carbon atoms of R ² include, for example, methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, sec-butyl group, t-butyl group. Group, n-pentyl group and the like, and examples of the acyl group having 1 to 6 carbon atoms include acetyl group, propionyl group, butyryl group, valeryl group and caproyl group. A plurality of R ^{2 s} in the general formula (1) may be the same or different from each other.

Specific examples of such organosilanes include tetraalkoxysilanes such as tetramethoxysilane, tetraethoxysilane, tetra-n-propoxysilane, tetra-i-propoxysilane and tetra-n-butoxysilane (above). , N = 4); methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, i-propyltrimethoxysilane, i. -Propyltriethoxysilane, n-butyltrimethoxysilane,
n-butyltriethoxysilane, n-pentyltrimethoxysilane, n-hexyltrimethoxysilane, n-heptyltrimethoxysilane, n-octyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, cyclohexyltrimethoxysilane, Cyclohexyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3-chloropropyltrimethoxysilane, 3-chloropropyltriethoxysilane, 3,3,3-trifluoropropyltrimethoxysilane, 3,3,3- Trifluoropropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 2-hydroxyethyltrimethoxysilane, 2-hydroxyethyltriethoxysilane , 2-hydroxypropyl trimethoxysilane, 2-hydroxypropyl triethoxysilane, 3-hydroxypropyl trimethoxysilane, 3
-Hydroxypropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane , 3-glycidoxypropyltriethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 3- (meth) acryloxypropyltri Trialkoxysilanes such as methoxysilane, 3- (meth) acryloxypropyltriethoxysilane, 3-ureidopropyltrimethoxysilane, and 3-ureidopropyltriethoxysilane (above, when n = 3, ); Dimethyldimethoxysilane,
Dimethyldiethoxysilane, diethyldimethoxysilane, diethyldiethoxysilane, di-n-propyldimethoxysilane, di-n-propyldiethoxysilane, di-i-propyldimethoxysilane, di-i-propyldiethoxysilane, di- n-butyldimethoxysilane, di-n-butyldiethoxysilane, di-n-pentyldimethoxysilane, di-n-pentyldiethoxysilane, di-n-hexyldimethoxysilane, di-n-hexyldiethoxysilane, di -N-heptyldimethoxysilane,
Di-n-heptyldiethoxysilane, di-n-octyldimethoxysilane, di-n-octyldiethoxysilane, di-n-cyclohexyldimethoxysilane, di-n
In addition to dialkoxysilanes such as cyclohexyldiethoxysilane, diphenyldimethoxysilane and diphenyldiethoxysilane (above, when n = 2), methyltriacetyloxysilane, dimethyldiacetyloxysilane and the like can be mentioned.

Of these, preferably used are
Trialkoxysilanes and dialkoxysilanes. Further, as the trialkoxysilanes, methyltrimethoxysilane and methyltriethoxysilane are preferable, and as the dialkoxysilanes, dimethyldimethoxysilane and dimethyldiethoxysilane. Is preferred.

The component (A ') used in the mini-emulsion polymerization of the present invention is at least one selected from organosilane (1), a hydrolyzate of the organosilane and a condensate of the organosilane. That is,
The component (A ′) may be only one of these three types, a mixture of any two types, or a mixture containing all three types. In the present invention,
It is preferable that the organosilane and the condensate of the organosilane are mixed and used. In the aqueous dispersion of the present invention, by co-condensing organosilane and its condensate, a coating having excellent properties such as hardness, chemical resistance, weather resistance, film-forming property, transparency, and crack resistance is formed. To form. Further, there is also an advantage that the polymerization stability when the vinyl compound is polymerized after the emulsification is remarkably improved and the polymerization can be carried out with a high solid content, which facilitates industrialization.

The organosilane condensate is used as the organosilane condensate by preliminarily hydrolyzing and condensing the organosilane. At this time, when the condensate is prepared, the organosilane is hydrolyzed by adding an appropriate amount of water to the organosilane and, if necessary, an organic solvent.
Condensation is preferred. Here, the amount of water used is usually 1.2 to 3.0 mol, preferably 1.3 to 2.0 mol, per 1 mol of organosilane.

At this time, as an organic solvent used as necessary, a condensate of organosilane or the after-mentioned (B) is used.
The components are not particularly limited as long as they can be mixed uniformly, and examples thereof include alcohols, aromatic hydrocarbons, ethers, ketones, and esters. Among these organic solvents, specific examples of alcohols include methanol, ethanol, n-propyl alcohol, i-propyl alcohol, n-butyl alcohol, sec-butyl alcohol, t-butyl alcohol, n-hexyl alcohol, n. -Octyl alcohol, 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 are benzene, toluene, xylene, etc., specific examples of the ethers are tetrahydrofuran, dioxane, etc., specific examples of the ketones are acetone, methyl ethyl ketone, Methyl isobutyl ketone, diisobutyl ketone and the like can be mentioned, and specific examples of the esters include ethyl acetate, propyl acetate, butyl acetate and propylene carbonate. These organic solvents may be used alone or in admixture of two or more. In the case where the condensate contains an organic solvent, the condensation
This organic solvent can be removed from the aqueous dispersion prior to the polymerization reaction.

The polystyrene reduced weight average molecular weight (hereinafter referred to as "Mw") of the condensate used as the component (A ') of the present invention is preferably 800 to 100,000, more preferably 1,000 to 50, It is 000.

Commercial products of (A) polyorganosiloxane [including a hydrolysis / condensation product of organosilane used as the component (A ')] include MKC silicate manufactured by Mitsubishi Chemical Corporation, manufactured by Colcoat Co., Ltd. Ethyl silicate, Toray Dow Corning Silicone resin, Toshiba Silicone Silicone resin, Shin-Etsu Chemical Co., Ltd. Silicone resin, Dow Corning Asia Ltd. hydroxyl group-containing polydimethylsiloxane , Nippon Yunika Co., Ltd. and the like, and these may be used as they are or after being condensed. More specific product names of commercially available products of this polyorganosiloxane include "SX101" and "SR2402" manufactured by Toray Dow Corning Silicone Co., Ltd., and "X40-9220" and "X40 manufactured by Shin-Etsu Chemical Co., Ltd. -922
5 "," KC89 "," DC3037 "," DC3074 "," SH "made by Toray Dow Corning Silicone Co., Ltd.
6018 "," DC6-2230 "and the like can be mentioned, and they can be preferably used.

When organosilane and its condensate are used as the component (A '), the mixing ratio of the two is 95 to 5% by weight, preferably 90 to 100% by weight of the organosilane (completely hydrolyzed condensate). 10% by weight, its condensate (in terms of complete hydrolysis condensate) is 5 to 95% by weight, preferably 1
0 to 90% by weight (however, organosilane + condensate = 1
00% by weight]. If the condensate is less than 5% by weight, (A
It is not preferable because it may be difficult to emulsify the mixture containing the component '), and the polymerization stability of the radically polymerizable monomer component (B') may decrease after emulsification, and the stability of the emulsion after emulsification may decrease. . On the other hand, if it exceeds 95% by weight, the proportion of the organosilane component becomes too small, and the film-forming property of the obtained organic-inorganic composite is deteriorated, which is not preferable.
Here, the above-mentioned completely hydrolyzed condensate, R ² O-group of the organosilane becomes 100% hydrolyzed to SiOH groups, more fully condensed refers to became siloxane structure.

(B) Acrylic Polymer (B) The acrylic monomer used in the acrylic polymer is, for example, (meth) acrylic acid; methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth). Acrylate, n-butyl (meth) acrylate, i-butyl (meth) acrylate, t-butyl (meth) acrylate, amyl (meth) acrylate, i-amyl (meth) acrylate, hexyl (meth) acrylate, 2-ethyl. Esters of (meth) acrylic acid such as hexyl (meth) acrylate, n-octyl (meth) acrylate, lauryl (meth) acrylate, cyclohexyl (meth) acrylate and isobornyl (meth) acrylate; 2-hydroxyethyl (meth) Acrylate, 2-hydroxypropyl Hydroxyl group-containing (meth) acrylic acid esters such as pill (meth) acrylate and 3-hydroxypropyl (meth) 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, butanediol di (meth)
Polyfunctional (meth) acrylic acid esters such as acrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate; trifluoroethyl (meth) acrylate, pentadecafluoro Fluorine atom-containing (meth) acrylic esters such as octyl (meth) acrylate; amino group-containing (such as 2-aminoethyl (meth) acrylate, 2-aminopropyl (meth) acrylate, 3-aminopropyl (meth) acrylate) ( (Meth) acrylic esters; (meth) acrylic compounds such as epoxy group-containing (meth) acrylic acid esters such as glycidyl (meth) acrylate.

Examples of the acrylic monomer include (meth)
Acrylic acid, (meth) acrylic acid ester, and hydroxyl group-containing (meth) acrylic acid ester are particularly preferable. More preferred are methyl methacrylate, cyclohexyl methacrylate, t-butyl methacrylate, butyl acrylate, 2-ethylhexyl acrylate, acrylic acid, methacrylic acid and 2-hydroxyethyl methacrylate.

In addition, the radical polymerizable monomer component (B ') includes styrene, α-methylstyrene, 4-methylstyrene, 2-methylstyrene, 3-methylstyrene,
4-methoxystyrene, 2-hydroxymethylstyrene, 4-ethylstyrene, 4-ethoxystyrene, 3,
4-dimethylstyrene, 3,4-diethylstyrene, 2
-Chlorostyrene, 3-chlorostyrene, 4-chloro-
3-methylstyrene, 4-t-butylstyrene, 2,4
-Dichlorostyrene, 2,6-dichlorostyrene, 1-
Aromatic vinyl monomers such as vinylnaphthalene; polyfunctional monomers other than the above, such as divinylbenzene;

(Meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth)
Acid amide compounds such as acrylamide, N-butoxymethyl (meth) acrylamide, N, N'-methylenebisacrylamide, diacetone acrylamide, maleic acid amide, maleimide; vinyl cyanide compounds such as acrylonitrile and methacrylonitrile; 4- (meth ) Acryloyloxy-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloylamino-2,
A piperidine-based monomer such as 2,6,6-tetramethylpiperidine or 4- (meth) acryloyloxy-1,2,2,6,6-pentamethylpiperidine; and dicaprolactone may be contained.

The above-mentioned (B ') monomer component contains, as a radical-polymerizable monomer having a functional group, unsaturated carboxylic acids other than the above, such as crotonic acid, maleic acid, fumaric acid and itaconic acid. Acids; unsaturated carboxylic acid anhydrides such as maleic anhydride and itaconic anhydride; hydroxyl group-containing vinyl monomers other than the above, such as N-methylol vinyl ether and 2-hydroxyethyl vinyl ether; amino groups such as 2-aminoethyl vinyl ether Containing vinyl-based monomer; 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-1- (2'-phenyl-2'-hydroxyethyl)
Amine (meth) acrylimide, 1,1-dimethyl-1
-(2'-hydroxy-2'-phenoxypropyl) amine (meth) acrylimide and other amine imide group-containing vinyl monomers; allyl glycidyl ether and other epoxy group-containing vinyl monomers You can

Further, the monomer component (B ') includes a radical polymerizable monomer having a dialkylamide group, a radical polymerizable monomer having a dialkylamino group, and a radical polymerizable monomer having a polyoxyethylene group. Those containing at least one selected from the monomers are preferable. (B
′) As a monomer component, a radical-polymerizable monomer having such a specific functional group is copolymerized to form a coating film excellent in frost damage resistance without lowering blocking resistance. be able to.

Here, as the radically polymerizable monomer having a dialkylamide group, N, N-dialkyl (meth) acrylamides such as N, N-dimethylacrylamide, N, N-diethylacrylamide, N, N-
Di (n-propyl) acrylamide, N, N-di (i-
Propyl) acrylamide, N, N-dimethylmethacrylamide, N, N-diethylmethacrylamide, N, N
-Di (n-propyl) methacrylamide, N, N-di (i-propyl) methacrylamide and the like can be mentioned, with preference given to N, N-dimethylacrylamide, N, N-dimethylmethacrylamide and N, N-. They are diethyl acrylamide and N, N-diethyl methacrylamide.

Further, as the radically polymerizable monomer having a dialkylamino group, 2-dimethylaminoethyl (meth) acrylate, 2-diethylaminoethyl (meth) acrylate, 2-dimethylaminopropyl (meth) acrylate, 3- Aminoalkyl group-containing (meth), such as dimethylaminopropyl (meth) acrylate
Examples thereof include acrylates, and preferably 2-dimethylaminoethyl acrylate, 2-dimethylaminoethyl methacrylate, 2-dimethylaminoethyl acrylate, and 2-dimethylaminoethyl methacrylate.

Further, the radical polymerizable monomer having a polyoxyethylene group is preferably an acrylic acid ester or a methacrylic acid ester having a polyoxyethylene chain, and specific examples thereof include Bremmer PE-9.
0, PE-200, PE-350, PME-100, P
ME-200, PME-400, AE-350 [above,
Nippon Oil & Fats Co., Ltd.], MA-30, MA-50, MA-
100, MA-150, RA-1120, RA-261
4, RMA-564, RMA-568, RMA-111
4, MPG130-MA [above, Nippon Emulsifier Co., Ltd.]
And so on. Here, the oxyethylene unit of the polyoxyethylene chain is preferably 2 to 30. Below 2,
If the effect of improving frost resistance is poor, on the other hand, if it exceeds 30, the coating becomes soft and the blocking resistance is poor.

In the monomer component (B '), a radical-polymerizable monomer other than the above acrylic monomer, particularly
The combined use of a radically polymerizable monomer having a specific functional group of improves the mechanical stability of the emulsion, improves the pigment dispersibility, and does not reduce the blocking resistance, and the freeze resistance. An excellent coating film can be formed. The content of the radically polymerizable monomer having the specific functional group in the component (B ′) is usually 10% by weight or less, preferably about 0.5 to 5% by weight.

The glass transition temperature of the acrylic polymer (B) in the aqueous dispersion of the present invention is -20 ° C to 80 ° C.
It is preferably 5 to 60 ° C. When the glass transition temperature is in this range, the effect of excellent balance of blocking resistance / frost resistance is obtained. This glass transition temperature can be easily adjusted by changing the type and ratio of the monomers.

The ratio of the component (A) to the component (B) in the aqueous dispersion of the present invention is 5 to 80 parts by weight, preferably 10 in terms of the total amount of the component (A) (in terms of complete hydrolysis condensate).
To 80 parts by weight, 95 to 20 parts by weight of component (B), preferably 90 to 20 parts by weight [where (A) + (B) = 10]
0 parts by weight]. Here, the weight part x of the component (A) is
Organosilane (1) is part by weight in the state of being completely hydrolyzed and condensed. However, in the composite particles contained in the aqueous dispersion of the present invention, the organosilane (1) does not necessarily have to be completely hydrolyzed and condensed, and normally, an unhydrolyzed alkoxy group or a condensed group is not condensed. Contains no silanol groups. The non-hydrolyzed alkoxy group and the non-condensed silanol group form a coating film having good weather resistance by dealcoholation reaction or dehydration reaction after coating. If the weight part x of the component (A) is less than 5 parts by weight, the weather resistance is poor, and if it exceeds 80 parts by weight, the adhesion is poor.

In the aqueous dispersion of the present invention, n in the organosilane represented by the general formula (1) which constitutes the component (A) is the organosilane 1 which is assumed to be the precursor of the component (A). Indicates the number of alkoxysilyl groups in the molecule. The number of alkoxysilyl groups in one molecule of the polymerizable organosilane can be 2, 3, and 4. When one or more of these organosilanes (1) are combined and hydrolyzed and condensed, the average amount of alkoxysilyl groups per Si atom in component (A) is n. In the aqueous dispersion of the present invention, the weight part x of the component (A) (in terms of complete hydrolysis-condensation product) and n of the general formula (1) constituting the component (A) are the following formula (2), preferably Is the following formula (2)
´ needs to be met. (−0.005x + 2.6) ≦ n ≦ (−0.005x + 3.3) (2) (−0.005x + 2.8) ≦ n ≦ (−0.005x + 3.1) (2) ′ Here As described above, n is the average amount of alkoxysilyl groups per Si atom in the component (A). n
Is less than (-0.005x + 2.6), blocking resistance is poor. On the other hand, if it exceeds (-0.005x + 3.3), frost damage resistance and crack resistance are poor.

Preparation of Aqueous Dispersion The aqueous dispersion of the present invention is
(A ') at least one selected from the group consisting of organosilane represented by the general formula (1), its hydrolyzate and its condensate; (B') the acrylic resin constituting the (B) acrylic polymer. A radical polymerizable monomer component containing a monomer and (C) an emulsifier are mixed to form an emulsion, and hydrolysis and condensation of the (A ′) component are promoted, and then the average particle diameter of the emulsion is adjusted to 0. It is obtained by finely reducing the particle size to 5 μm or less, and then radically polymerizing the monomer component (B ′) by adding the radical polymerization initiator (D).

(C) Emulsifiers Examples of surfactants used as emulsifiers include anionic surfactants such as alkyl sulfate ester salts, alkylaryl sulfate ester salts, alkyl phosphate ester salts and fatty acid salts; alkyl amine salts, alkyl salts. Cationic surfactants such as quaternary amine salts; nonionic surfactants such as polyoxyethylene alkyl ethers, polyoxyethylene alkylaryl ethers, block type polyethers; carboxylic acid type (for example, amino acid type, betaine acid type, etc.) ), Amphoteric surfactants such as sulfonic acid type,
With the trade name, Latemur S-180A [manufactured by Kao Corporation], Eleminol JS-2 [manufactured by Sanyo Kasei Co., Ltd.], Aqualon HS-10 [manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.], Adecaria Soap SE-10N [Made by Asahi Denka Co., Ltd.]], Antox
Any reactive emulsifier such as MS-60 (manufactured by Nippon Emulsifier Co., Ltd.) can be used. In particular, the use of a reactive emulsifier is preferable because it is excellent in weather resistance and water resistance.

As the above reactive emulsifier, a reactive emulsifier having a polyoxyethylene chain is particularly preferable. Here, the reactive emulsifier having a polyoxyethylene chain,
An emulsifier having a hydrophobic group such as an alkyl group having 8 or more carbon atoms in one molecule, a hydrophilic group containing a polyoxyethylene chain, and a radical-polymerizable unsaturated double bond. The end of the polyoxyethylene chain may be esterified with a sulfonate or the like.

Among the reactive emulsifiers having a polyoxyethylene chain, those not esterified at the ends include, for example, ADEKA REASOAP NE-20 and NE-3.
0, NE-40 [product name, manufactured by Asahi Denka Kogyo Co., Ltd.] α- [1-[(allyloxy) methyl] -2- (nonylphenoxy) ethyl] -ω-hydroxypolyoxyethylene, or Aqualon RN -10, RN-20, RN
-30, RN-50 [Product name, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.]
Examples thereof include nonionic surfactants such as polyoxyethylene alkylpropenyl phenyl ether, which are referred to as reactive nonionic surfactants and which are copolymerizable with an ethylenically unsaturated monomer.

Among the reactive emulsifiers having a polyoxyethylene chain, those having an esterified end include, for example, Eleminol JS-2 and JS-5 (product name, manufactured by Sanyo Kasei Co., Ltd.), Latemur S-120, S-1
80A, S-180 [product name, manufactured by Kao Corporation], Aqualon HS-10 [product name, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.], ADEKA REASOAP SE-1025N [product name, Asahi Denka Kogyo Co., Ltd.] Manufactured] and the like. In particular, by using a non-reactive emulsifier such as sodium dodecylbenzenesulfonate together with the reactive emulsifier, the polymerization stability and the weather resistance can be balanced. The above emulsifiers are
These may be used alone or in combination of two or more.

The amount of the emulsifier used is usually 0.1 to 5 parts by weight, preferably 0, based on 100 parts by weight of the total amount of the component (A ') (completely hydrolyzed condensate) and the component (B'). .2
-4 parts by weight, more preferably 0.5-2 parts by weight. If it is less than 0.1 part by weight, the emulsification is not sufficient, and
Stability during hydrolysis / condensation and radical polymerization decreases, which is not preferable. On the other hand, when it exceeds 5 parts by weight, foaming becomes a problem, which is not preferable.

In the production of the aqueous dispersion of the present invention, water is usually used as the aqueous medium. The water may be water present in a water-based mixed solution of the component (A ′) that has been added in advance, or may be water that is further added to the mixture of the component (A ′) together with the (C) emulsifier. May be. The amount of water used is usually 50 to 2,000 parts by weight, preferably 80 to 2,000 parts by weight, based on 100 parts by weight of the total amount of the component (A ′) (completely hydrolyzed condensate) and the component (B ′).
The amount is 1,000 parts by weight, more preferably 100 to 500 parts by weight. If it is less than 50 parts by weight, emulsification is difficult or the stability of the emulsion after emulsification is lowered, which is not preferable. On the other hand, if it exceeds 2,000 parts by weight, the productivity is lowered, which is not preferable.

Hydrolysis Catalyst Incidentally, in order to prepare the aqueous dispersion of the present invention, usually (A
A catalyst that accelerates the hydrolysis / condensation reaction of the component ') is used. By using the hydrolysis catalyst, as described above, the stability during radical polymerization is improved, and the molecular weight of the polysiloxane resin produced by the polycondensation reaction of the component (A ′) used is increased and the strength is increased. In addition, it is possible to obtain a coating film excellent in long-term durability and the like, and it becomes easy to increase the thickness of the coating film and to perform painting work.

As such a hydrolysis catalyst, an acidic compound, an alkaline compound, a salt compound, an amine compound, an organometallic compound and / or a partial hydrolyzate thereof (hereinafter referred to as an organometallic compound and / or a partial hydrolyzate thereof) is used. Collectively referred to as "organometallic compound") is preferred.
Examples of the acidic compound include (meth) acrylic acid, itaconic acid, acetic acid, hydrochloric acid, sulfuric acid, phosphoric acid, alkyltitanic acid, p-toluenesulfonic acid, dodecylbenzenesulfonic acid, and phthalic acid. Of these, acetic acid and dodecylbenzenesulfonic acid are preferable. Examples of the alkaline compound include sodium hydroxide and potassium hydroxide, and sodium hydroxide is preferable. Examples of the salt compound include naphthenic acid, octylic acid, nitrous acid, sulfurous acid, aluminate, carbonic acid, and other alkali metal salts.

Examples of the amine compound include ethylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, piperidine, piperazine, m-phenylenediamine, p-phenylenediamine, ethanolamine, triethylamine, 3 -Aminopropyl trimethoxysilane, 3-aminopropyl triethoxysilane, 3- (2-aminoethyl) -aminopropyl trimethoxysilane, 3- (2-aminoethyl) -aminopropyl triethoxysilane, 3 -(2-aminoethyl) -aminopropyl methyl dimethoxysilane, 3
In addition to anilinopropyl trimethoxysilane, alkylamine salts and quaternary ammonium salts, various modified amines used as a curing agent for epoxy resins can be mentioned, and preferably 3-aminopropyltrimethoxysilane. , 3-aminopropyl triethoxysilane, and 3- (2-aminoethyl) -aminopropyl trimethoxysilane.

Examples of the organometallic compound and the like include, for example, a compound represented by the following general formula (3) (hereinafter referred to as "organometallic compound (3)"), having 1 to 1 carbon atoms bonded to the same tin atom. Examples thereof include tetravalent tin organometallic compounds having 1 to 2 alkyl groups of 10 (hereinafter referred to as "organotin compound"), partial hydrolysates of these compounds, and the like.

[0047] [In the formula, M is zirconium, titanium or aluminum
Indicates R³And R^FourAre the same or different and are ethyl
Group, n-propyl group, i-propyl group, n-butyl group,
sec-butyl group, t-butyl group, n-pentyl group, n
-Hexyl group, cyclohexyl group, phenyl group, etc.
Represents a monovalent hydrocarbon group having a prime number of 1 to 6, R ^FiveIs R³And
And R^FourSimilar to C1-6 monovalent hydrocarbon groups
Or methoxy group, ethoxy group, n-propoxy group, i-
Propoxy group, n-butoxy group, sec-butoxy group,
t-butoxy group, lauryloxy group, stearyloxy
Represents an alkoxyl group having 1 to 16 carbon atoms, such as
And s are integers from 0 to 4, (r + s) = (valence of M)
Is. ]

Specific examples of the organometallic compound (3) include (a) tetra-n-butoxyzirconium and tri-n-
Butoxy / ethylacetoacetate zirconium, di-
n-butoxy bis (ethylacetoacetate) zirconium, n-butoxy tris (ethylacetoacetate) zirconium, tetrakis (n-propylacetoacetate) zirconium, tetrakis (acetylacetoacetate) zirconium, tetrakis (ethylacetoacetate) zirconium, etc. An organic zirconium compound of

(B) Tetra-i-propoxytitanium, di-i-propoxybis (ethylacetoacetate) titanium, di-i-propoxybis (acetylacetate) titanium, di-i-propoxybis (acetylacetone) Organic titanium compounds such as titanium; (C) tri-i-propoxyaluminum, di-i-propoxyethylacetoacetate aluminum, di-
i-propoxy acetylacetonate aluminum,
i-Propoxy bis (ethyl acetoacetate) aluminum, i-propoxy bis (acetyl acetonate) aluminum, tris (ethyl acetoacetate)
Examples thereof include organic aluminum compounds such as aluminum, tris (acetylacetonato) aluminum, monoacetylacetonate / bis (ethylacetoacetate) aluminum, and the like.

Among these organometallic compounds (3) and partial hydrolysates thereof, tri-n-butoxy ethyl acetoacetate zirconium, di-i-propoxy bis (acetylacetonato) titanium, di-i-propoxy.・ Aluminum ethyl acetoacetate, tris (ethyl acetoacetate) aluminum, or
Partial hydrolysates of these compounds are preferred.

Specific examples of the organotin compound include:
_{(C 4 H 9) 2 Sn} (OCOC 11 H 23) 2, (C 4 H 9) 2
_{Sn (OCOCH = CHCOOCH 3) 2} , (C 4 H 9)
₂ Sn (OCOCH = CHCOOC ₄ H ₉ ) 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 (OCOC
H = CHCOOCH ₃ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (OCO
CH = CHCOOC ₄ H ₉ ) ₂ , (C ₈ H ₁₇ ) ₂ Sn (O
COCH = CHCOOC ₈ H ₁₇ ) 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 , _{(C 4 H 9) Sn (} OCOC 11 H 23) 3, (C 4 H 9) S
a carboxylic acid type organic tin compound such as n (OCONa) ₃ ;

(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) Sn (SCOCH = CHCOO
_{C 8 H 17) 3, (} C 8 H 17) Sn (SCOCH = CHC
OOC ₈ H ₁₇ ) ₃ ,

[0053] Mercaptide type organotin compounds such as;

(C ₄ H ₉ ) ₂ Sn = S, (C ₈ H ₁₇ ) ₂ Sn
= S, Sulfide type organotin compounds such as;

(C ₄ H ₉ ) SnCl ₃ , (C ₄ H ₉ ) ₂ Sn
Cl ₂ , (C ₈ H ₁₇ ) ₂ SnCl ₂ , Chloride type organotin compounds such as; (C ₄ H ₉ ) ₂ Sn
O, organotin oxides such as (C ₈ H ₁₇ ) ₂ SnO,
Reaction products of these organic tin oxides with ester compounds such as silicate, dimethyl maleate, diethyl maleate and dioctyl phthalate;

As the hydrolysis catalyst, acrylic acid,
With unsaturated carboxylic acids such as methacrylic acid,
Since the component (B ') is copolymerized, the effect that weather resistance and water resistance are not deteriorated can be obtained.

The amount of the hydrolysis catalyst used is usually 0.01 to 5 parts by weight, based on 100 parts by weight of the above-mentioned component (A ') (calculated as a complete hydrolysis-condensation product) and component (B').
Preferably 0.1 to 5 parts by weight, more preferably 0.1
~ 3 parts by weight. If it is less than 0.01 part by weight, the hydrolysis and condensation reaction of the component (A) may be insufficient, while
If it exceeds 5 parts by weight, the storage stability of the aqueous dispersion tends to deteriorate, and the coating film tends to crack.

(D) Radical Polymerization Initiator A radical polymerization initiator is used in the condensation / polymerization reaction. Examples of the radical polymerization initiator include persulfates such as potassium persulfate, sodium persulfate and ammonium persulfate, hydrogen peroxide, t-butyl hydroperoxide, t-butyl peroxymaleic acid, succinic acid peroxide, 2,2. Water-soluble initiators such as ′ -azobis [2-N-benzylamidino] propane hydrochloride; benzoyl peroxide, cumene hydroperoxide, diisopropyl peroxydicarbonate, cumyl peroxy neodecanoate, cumyl peroxy octoate,
An oil-soluble initiator such as azobisisobutyronitrile; a redox initiator in combination with a reducing agent such as sodium acid sulfite, Rongalit, and ascorbic acid can be used. Among these components (D), a water-soluble initiator is preferable from the viewpoint of polymerization stability. The amount of these radical polymerization initiators used is 100 parts by weight in total of the component (A ′) (in terms of complete hydrolysis condensate) and the component (B ′).
0.01-5 parts by weight, preferably 0.05-4 parts by weight,
More preferably, it is 0.1 to 3 parts by weight. 0.
If it is less than 01 parts by weight, the radical polymerization reaction may be deactivated in the middle of the reaction, while if it exceeds 5 parts by weight, the weather resistance may be poor.

(E) Light Stabilizer In the aqueous dispersion of the present invention, during the above emulsification,
(E) A light stabilizer substantially insoluble in water may be contained. In the present invention, in a normal emulsion polymerization, a light stabilizer which is difficult to dissolve in water, which cannot be introduced at the time of polymerization, can be introduced into the composite particles of the present invention by miniemulsion polymerization, resulting in excellent weather resistance. A coated film can be formed. Here, "substantially insoluble in water" means that the solubility in water is 0.1% by weight or less, preferably 0.01% by weight or less. When such a light stabilizer is exposed outdoors, the light stabilizer is prevented from flowing out due to rain, and the weather resistance is improved.

Examples of the component (E) include hindered amine light stabilizers, and specific examples thereof include bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate and bis (1,2). , 2,6,6-Pentamethyl-
4-piperidyl) sebacate, 4-benzoyloxy-
2,2,6,6-Tetramethylpiperidine, tetraxy (2,2,6,6-tetramethyl-4-piperidyl)-
Examples include hindered amine light stabilizers such as 1,2,3,4-butanetetracarboxylate.

As the hindered amine light stabilizer as the component (E), those having low basicity are preferable, and specifically those having a base constant (pKb) of 8 or more are preferable. Specifically, 1- [2- [3- (3,5-di-te
rt-Butyl-4-hydroxyphenyl) propynyloxy] ethyl] -4- [3- (3,5-di-tert-
Butyl-4-hydroxyphenyl) propynyloxy]
-2,2,6,6-tetramethylpiperidine, bis (1
-Octoxy-2,2,6,6-tetramethyl-4-piperidyl) sebacate [TINUVIN123 (product name, manufactured by Nippon Ciba-Geigy Co., Ltd.), 8-acetyl-3-
Dodecyl-7,7,9,9-tetramethyl-1,3,8
-Triazaspiro [4,5] decane-2,4-dione and the like.

Of these (E) light stabilizers, bis (2,2,6,6-tetramethyl-4-piperidyl) succinate and bis (2,2,6,6-tetramethylpiperidyl) are preferred. Sebacate, screw (1, 2, 2, 6,
6-pentamethyl-4-piperidyl) 2- (3,5-di-tert-butyl-4-hydroxybenzyl) -2-
Butyl malonate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate and methyl-1,
Mixture of 2,2,6,6-pentamethyl-4-piperidyl-sebacate (manufactured by Nippon Ciba Geigy Ltd., product name:
TINUVIN292), bis (1-octoxy-2,
2,6,6-Tetramethyl-4-piperidyl) sebacate, TINUVIN123 (product name, manufactured by Ciba-Geigy Co., Ltd.), 1- [2- [3- (3,5-di-t
-Butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4- [3- (3,5-di-t-butyl-
4-hydroxyphenyl) propionyloxy] -2,
2,6,6-tetramethylpiperidine, 8-acetyl-
3-dodecyl-7,7,9,9-tetramethyl-1,
3,8-Triazaspiro [4,5] decane-2,4-dione may be mentioned.

The light stabilizer (E) is used in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the component (A ') (completely hydrolyzed condensate) and the component (B'). The amount is preferably 0.2 to 5 parts by weight, more preferably 0.5 to 3 parts by weight. If it is less than 0.1 parts by weight, the effect of improving the weather resistance is low, while if it exceeds 10 parts by weight, the surface tends to be tacky and easily soiled, and the blocking resistance may be lowered.

(F) Poly (meth) acrylate In the aqueous dispersion of the present invention, the weight average molecular weight of polystyrene (F) is 100 at the time of the emulsification.
0 to 10,000, preferably 1,000 to 5,000
The poly (meth) acrylate may be included. By allowing a poly (meth) acrylate having a specific molecular weight to coexist during the miniemulsion polymerization of the present invention, a coating film having excellent blocking resistance can be formed without lowering frost resistance. Here, the above (F) poly (meta)
The acrylate can be obtained by solution polymerization of (meth) acrylic acid esters such as methyl methacrylate, ethyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate together with a chain transfer agent such as dodecyl mercaptan, if necessary. (F)
The component may contain a functional group such as hydroxyethyl methacrylate, acrylic acid, methacrylic acid, or (meth) acrylate containing a siloxane group. The component (F) is industrially manufactured by Soken Chemical Co., Ltd.
-300 "(molecular weight 3,800)," Actflow UM
B-1001 "(molecular weight 1,500)," Actflow UME-1001 "(molecular weight 2000)," Actflow CBL-3098 "(molecular weight 4,000) and the like. If the weight average molecular weight of the component (F) in terms of polystyrene is less than 1,000, it is not effective in improving the blocking resistance, while if it exceeds 10,000, the particle size becomes large and the weather resistance and adhesion are poor. There is.

The amount of the (F) poly (meth) acrylate used is 0.1 to 1 with respect to 100 parts by weight of the total of the component (A ′) (completely hydrolyzed condensate) and the component (B ′).
It is 0 part by weight, preferably 0.2 to 5 parts by weight, more preferably 0.5 to 3 parts by weight. Below 0.1 parts by weight,
If it exceeds 10 parts by weight, the particle size becomes large, and the weather resistance and the adhesion may be poor.

By the way, when a polymer emulsion is produced, most are produced by emulsion polymerization. Emulsion polymerization is usually several μm to several mm from large monomer oil droplets, while the monomer molecule moves through an aqueous solvent to an emulsifier micelle of several nm, the polymerization proceeds, and finally several hundred nm. Polymer particles having a particle size of On the other hand, the mini-emulsion polymerization in the present invention is a method in which the monomer oil droplets are finely emulsified in advance to a desired particle size, and the polymerization is advanced / completed with the particle size maintained. This is a polymerization method used particularly when polymerizing a hydrophobic monomer because it does not require transfer. The highly durable emulsion of the present invention can be radically polymerized by miniemulsion polymerization to polymerize an emulsion containing more polyorganosiloxane with good polymerization stability.

That is, the aqueous dispersion of the present invention comprises the above-mentioned components (A ') to (B') and (C), or
After the components (A ′) to (B ′) and the component (C) and the components (E) and / or (F) are mixed to form an emulsion, hydrolysis of the component (A ′) is promoted (hereinafter referred to as “ Also referred to as "emulsification"), and the average particle diameter of the emulsion is reduced to 0.5 μm or less (hereinafter also referred to as "refining"). Then, the radical polymerization initiator (D) is added to perform radical polymerization (miniemulsion polymerization). ) Is obtained.

Here, the conditions for emulsification are:
The components (A ′) to (B ′) and the component (C), or the mixture of the components (A ′) to (B ′) and the component (C) and the components (E) and / or (F) is a liquid. It suffices that the mixture is visually agitated under a uniform temperature and pressure in a uniform mixed state. By this emulsification, the above respective components are homogenized and emulsified, and the hydrolysis of the component (A ′) proceeds. For micronization, a high pressure homogenizer, ultrasonic waves, a mechanical means such as a homomixer is used to make the water system into a miniemulsion. At this time, the average particle diameter of the emulsion is 0.5 μm or less, preferably 0.0
It is set to 5 to 0.2 μm. If it exceeds 0.5 μm, the water resistance is poor, which is not preferable.

Further, in the radical polymerization reaction, (co) condensation of the component (A ′) (preferably a mixture of organosilane and its condensate) and (B ′) the monomer component under a finely emulsified state. Radical polymerization proceeds at the same time. In addition, (A
The reaction when the component ′) is a mixture of organosilane and its condensate includes not only the above-mentioned two types of co-condensation but also the case where the organosilane and the condensate are each independently subjected to a condensation reaction. As a result, the siloxane component composed of the component (A) and the acrylic polymer composed of the component (B) form an interpenetrating network structure. Further, in the emulsion particles, the polymers are entangled in a solventless state, so that the degree of freedom of the silanol group having a high condensation activity in the siloxane component is limited,
The condensation is suppressed and good storage stability is obtained.

The reaction conditions for the radical polymerization reaction at this time are such that the temperature is usually 25 to 100 ° C., preferably 40.
The reaction time is usually 0.5 to 15 hours, preferably 1 to 8 hours.

In the radical polymerization reaction, (A
When the component ') or the component (B') has an acidic group such as a carboxyl group or a carboxylic acid anhydride group, at least one basic compound is added to the pH after the condensation / polymerization reaction.
Is preferably adjusted. On the other hand, when each of the above components has basicity such as an amino group or an amine imide group,
After the condensation / polymerization reaction, it is preferable to add at least one acidic compound to adjust the pH. Furthermore, in the case where each of the above components has an acidic group and a basic group, at least 1 depending on the ratio of these groups after the condensation / polymerization reaction.
Add a basic compound or acidic compound to the pH
In any case, the hydrophilicity of the resulting aqueous dispersion can be increased to improve the dispersibility, and the condensation reaction of silanol groups in the composite particles can be prevented during storage.

Examples of the basic compound include amines such as ammonia, methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, ethanolamine, diethanolamine and dimethylaminoethanol; alkaline metal hydroxides such as caustic potash and caustic soda. The thing etc. are mentioned.
Examples of the acidic compound include inorganic acids such as hydrochloric acid, phosphoric acid, sulfuric acid, nitric acid; formic acid, acetic acid, propionic acid, lactic acid, oxalic acid, citric acid, adipic acid, (meth) acrylic acid, maleic acid, Examples include organic acids such as fumaric acid and itaconic acid. The pH value of the aqueous dispersion during the pH adjustment is usually 5 to 10, preferably 6 to 7.

In the water-based dispersion of the present invention, the organic-inorganic composite is dispersed in the water-based medium, and the dispersed state can be in the form of particles or an aqueous sol. In this case, the average particle size of the organic-inorganic composite of the present invention is usually 0.01
˜0.5 μm, preferably 0.05 to 0.2 μm. The solid content concentration of the aqueous dispersion of the present invention is usually
It is 10 to 60% by weight, preferably 20 to 50% by weight. This solid content concentration is usually adjusted by the amount of water. The aqueous medium in the aqueous dispersion of the present invention consists essentially of water, but may optionally contain an organic solvent such as alcohol up to several wt%.
In addition, when the aqueous dispersion of the present invention contains an organic solvent which is optionally used in the preparation of the component (A),
This organic solvent can also be removed from the aqueous dispersion. Further, in the aqueous dispersion of the present invention, if necessary, various organic solvents as described above used when preparing the component (A) can be added. In addition, it is desirable that the flammable organic solvent is reduced by heating, distillation or the like so as not to have flammability.

(G) Silane Coupling Agent The aqueous dispersion of the present invention may contain (G) a silane coupling agent. The silane coupling agent (G) can form a siloxane bond such as a polymerizable unsaturated group capable of radical polymerization with the monomer component (B ′) and an alkoxysilyl group capable of cocondensation with the component (A). It is a compound having a group. When the (G) silane coupling agent is contained in the water-based dispersion of the present invention, the hybrid property of the organic component and the inorganic component of the water-based dispersion of the present invention is improved, so that crack resistance during film formation and transparency are improved. And weather resistance are improved. To add this (G) silane coupling agent, it may be added to the mixed solution of the above-mentioned (A ′) component and (B ′) component before emulsification, or may be added during the above condensation / polymerization. Well, it may be added after the preparation of the aqueous dispersion of the present invention. Preferably, before emulsification, the above (A ′)
It is preferably added to the mixed liquid of the component and the component (B ').

Specific examples of (G) silane coupling agents include CH ₂ ═CHSi (CH ₃ ) (OCH ₃ ) ₂ , CH
_{2 = CHSi (OCH 3) 3} , CH 2 = CHSi (CH 3)
Cl ₂ , CH ₂ = CHSiCl ₃ , CH ₂ = CHCOO
_{(CH 2) 2 Si (CH} 3) (OCH 3) 2, CH 2 = CHC
_{OO (CH 2) 2 Si (} OCH 3) 3, CH 2 = CHCO
_{O (CH 2) 3 Si (} CH 3) (OCH 3) 2, CH 2 = CH
_{COO (CH 2) 3 Si (} OCH 3) 3, CH 2 = CHCO
_{O (CH 2) 2 Si (} CH 3) Cl 2, CH 2 = CHCOO
_{(CH 2) 2 SiCl 3,} CH 2 = CHCOO (CH 2) 3
_{Si (CH 3) Cl 2,} CH 2 = CHCOO (CH 2) 3 S
iCl ₃ , CH ₂ = C (CH ₃ ) COO (CH ₂ ) ₂ Si
_{(CH 3) (OCH 3)} 2, CH 2 = C (CH 3) COO
_{(CH 2) 2 Si (OCH} 3) 3, CH 2 = C (CH 3) C
_{OO (CH 2) 3 Si (} CH 3) (OCH 3) 2, CH 2 = C
_{(CH 3) COO (CH 2} ) 3 Si (OCH 3) 3, CH 2 =
C (CH ₃ ) COO (CH ₂ ) ₂ Si (CH ₃ ) Cl ₂ , C
H ₂ ═C (CH ₃ ) COO (CH ₂ ) ₂ SiCl ₃ , CH _{2
= C (CH 3) COO (} CH 2) 3 Si (CH 3) Cl 2,
_{CH 2 = C (CH 3)} COO (CH 2) 3 such as SiCl ₃ and the like. (G) The compounding amount of the silane coupling agent is
Component (A ') (in terms of complete hydrolysis condensate) and (B
It is usually 20 parts by weight or less, preferably 10 parts by weight, based on 100 parts by weight of the total of the component '.

Component (H) The powder and / or sol or colloid of the inorganic compound (H) is added to the aqueous dispersion of the present invention according to the desired properties of the coating film. When the component (H) is in the form of a sol or colloid, its average particle size is usually 0.00
It is about 1 to 100 μm.

Specific examples of the compound forming the component (H)
Is TiO₂  , TiO₃  , SrTiO₃, FeTi
O₃, WO₃, SnO₂, Bi₂O₃, In₂O₃  , Zn
O, Fe₂O₃, RuO₂, CdO, CdS, CdSe,
GaP, GaAs, CdFeO₃, MoS₂, LaRhO
₃, GaN, CdP, ZnS, ZnSe, ZnTe, N
b₂O_Five, ZrO₂, InP, GaAsP, InGaAl
P, AlGaAs, PbS, InAs, PbSe, In
In addition to photocatalytic semiconductors such as Sb, SiO₂,
Al₂O₃, AlGa, As, Al (OH)₃, Sb
₂O_Five, Si₃N_Four, Sn-In₂O ₃, Sb-In₂O₃  ,
MgF, CeF₃, CeO₂  3 Al₂O₃・ 2Si
O₂, BeO, SiC, AlN, Fe, Co, Co-F
eOx, CrO₂, Fe_FourN, BaTiO₃, BaO-A
l₂O₃-SiO₂, Ba ferrite, SmCO_Five, YCO
_Five, CeCO_Five  PrCO_Five, Sm₂CO₁₇, Nd₂Fe₁₄
B, Al_FourO₃, Α-Si, SiN_Four, CoO, Sb-S
nO₂, Sb₂O_Five, MnO₂, MnB, Co₃O_Four, Co₃
B, LiTaO₃, MgO, MgAl₂O_Four, BeAl₂O
_Four, ZrSiO_Four, ZnSb, PbTe, GeSi, Fe
Si₂, CrSi₂, CoSi₂, MnSi_{1.7 3}, Mg₂S
i, β-B, BaC, BP, TiB₂, ZrB₂, HfB
₂, Ru₂Si ₃, TiO₂(Rutile type), TiO₃, Pb
TiO₃, Al₂TiO_Five, Zn₂SiO_Four, Zr₂Si
O_Four2MgO₂-Al₂O₃-5 SiO₂, Nb₂O_Five, L
i₂O-Al₂O₃-4 SiO₂, Mg ferrite, Ni foil
Elite, Ni-Zn ferrite, Li ferrite, S
An example is r-ferrite. These (H)
Ingredients may be used alone or in admixture of two or more.
You can

The component (H) is present in the form of powder, an aqueous sol or colloid dispersed in water, a polar solvent such as isopropyl alcohol, or a solvent sol or colloid dispersed in a nonpolar solvent such as toluene. There is. In the case of a solvent-based sol or colloid, depending on the dispersibility of the semiconductor, it may be diluted with water or a solvent and used, or may be surface-treated to improve the dispersibility.
When the component (H) is an aqueous sol or colloid, or a solvent sol or colloid, the solid content concentration is preferably 40% by weight or less.

As a method for blending the component (H) into the aqueous dispersion, the component (H) may be added after the preparation of the aqueous dispersion, or the component (H) may be added at the time of the preparation of the aqueous dispersion.
You may co-hydrolyze and condense with the said (A ') component etc.

The amount of the component (H) used is usually 500 parts by weight in terms of solid content based on 100 parts by weight of the total amount of the above components (A ') (calculated as a complete hydrolysis-condensation product) and the component (B'). Parts or less, preferably 0.1 to 400 parts by weight.

Other Additives Further, in the aqueous dispersion of the present invention, coloring of the obtained coating film,
A filler may be added and dispersed separately to increase the film thickness. Examples of such fillers include water-insoluble organic pigments and inorganic pigments, other than pigments, particulate, fibrous or scaly ceramics, metals or alloys,
In addition, oxides, hydroxides, carbides, nitrides and sulfides of these metals can be mentioned.

Specific examples of the above-mentioned fillers include iron, copper, aluminum, nickel, silver, zinc, ferrite, carbon black, stainless steel, silicon dioxide, titanium oxide for pigments, aluminum oxide, chromium oxide, manganese oxide, and oxidation. Iron, zirconium oxide, cobalt oxide, synthetic mullite, aluminum hydroxide, iron hydroxide, silicon carbide,
Silicon nitride, boron nitride, clay, diatomaceous earth, slaked lime, gypsum, talc, barium carbonate, calcium carbonate, magnesium carbonate, barium sulfate, bentonite, mica,
Zinc green, chrome green, cobalt green, viridian, Guinea green, cobalt chrome green, schele green, green soil, manganese green, pigment green, ultramarine blue, dark blue, pigment green, rock ultramarine blue, cobalt blue, cerulean blue, copper borate, Molybdenum blue, copper sulfide, cobalt purple, mars purple, manganese purple, pigment violet, lead suboxide, calcium leadate, zinc yellow, lead sulfide, chrome yellow, loess, cadmium yellow, strontium yellow, titanium yellow, litharge,
Pigment yellow, cuprous oxide, cadmium red, selenium red, chrome vermillion, red iron oxide, zinc white, antimony white, basic lead sulfate, titanium white, lithopone, lead silicate,
Zircon oxide, tungsten white, lead, zinc white, bunchison white, lead phthalate, manganese white, lead sulfate, graphite, bone black, diamond black, thermatomic black, vegetable black, potassium titanate whiskers, molybdenum disulfide, etc. Can be mentioned. These fillers can be used alone or in admixture of two or more. The amount of the filler used is usually 300 parts by weight or less based on 100 parts by weight of the total amount of the component (A ′) (completely hydrolyzed condensate) and the component (B ′).

Furthermore, if desired, the aqueous dispersion of the present invention contains polyoxyethylene alkyl ether, polyoxyethylene alkylphenyl ether, polyoxyethylene fatty acid ester, polycarboxylic acid type polymer surfactant, and polycarboxylic acid salt. Dispersants such as polyphosphates, polyacrylates, polyamide ester salts, polyethylene glycols; celluloses such as methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, hydroxypropylmethylcellulose, castor oil derivatives, ferrosilicates, etc. Thickeners: inorganic foaming agents such as ammonium carbonate, ammonium hydrogencarbonate, ammonium nitrite, sodium borohydride, calcium azide, and azo compounds such as azobisisobutyronitrile. , 3,3'
In addition to organic blowing agents such as hydrazine compounds such as disulfohydrazine, semicarbazide compounds, triazole compounds and N-nitroso compounds, other additives such as surfactants, titanium coupling agents and dyes can also be added. In particular, when the aqueous dispersion of the present invention is used in the overcoating composition, for the purpose of improving weather resistance and durability adhesion,
You may mix | blend a ultraviolet absorber, an ultraviolet stabilizer, etc. Examples of the UV absorber include inorganic semiconductors such as ZnO, TiO ₂ (which does not exhibit a photocatalytic function) and CeO ₂ ; organic UV absorbers such as salicylic acid-based, benzophenone-based, benzotriazole-based, cyanoacrylate-based and triazine-based Is mentioned. Further, examples of the ultraviolet stabilizer include piperidine-based stabilizers.

Further, a leveling agent may be added in order to further improve the coating property of the aqueous dispersion of the present invention. Among such leveling agents, examples of the fluorine-based leveling agent (trade name; hereinafter the same) include, for example,
BM100 from BM-CHEMIE
0, BM1100; Fuka 77 from Fuka Chemicals
2, Fuka 777; Floren series manufactured by Kyoeisha Chemical Co., Ltd .; FC series manufactured by Sumitomo 3M Limited; Fluoronal TF series manufactured by Toho Chemical Co., Ltd., and the like. Examples of silicone-based leveling agents include: BYK series of Big Chem; Shmego series of Shmegmann; Efka 30, Efka 31, Efka 34, Efka 35, Efka 36, Efka 39, Efka 83, Efka 86, Efka 88, etc. of Efka Chemicals. Examples of the ether-based or ester-based leveling agent include Carfinol manufactured by Nisshin Chemical Industry Co., Ltd .; Emulgen and homogenol manufactured by Kao Corporation.

By blending such a leveling agent, the finished appearance of the coating film is improved and it can be applied uniformly as a thin film. The amount of leveling agent used is
The content is preferably 5% by weight or less, more preferably 3% by weight or less, based on the aqueous dispersion (calculated as solid content).

The leveling agent may be added in preparing the aqueous dispersion of the present invention, or in the aqueous dispersion at the stage of forming a coating film, and further in the aqueous system. It may be added at both the stage of preparing the dispersion and the step of forming the coating film.

The aqueous dispersion of the present invention may be blended with other resins. Examples of other resins include acrylic-urethane resins, epoxy resins, polyesters, acrylic resins, fluororesins, acrylic resin emulsions, epoxy resin emulsions, polyurethane emulsions and polyester emulsions.

The total solid content concentration of the aqueous dispersion of the present invention containing the other components prepared as described above is usually
The amount is 10 to 55% by weight, preferably 15 to 50% by weight, and is appropriately adjusted according to the purpose of use. If the total solid content concentration exceeds 55% by weight, the storage stability tends to decrease.

Coating Material / Painted Body The aqueous dispersion of the present invention is used as a coating material (paint) as it is or by blending the additives after the above (G) silane coupling agent. be able to. In addition, these aqueous dispersions of the present invention can be used as a coating composition for undercoat as well as a coating composition for topcoat.

As the coating material, (B
′) As the component, an aqueous dispersion obtained by using a radically polymerizable monomer containing an aldo group and / or a keto group in an amount of 0.5 to 20% by weight, preferably 1 to 10% by weight,
It is preferable to add a crosslinking agent having two or more hydrazide groups before coating. Here, as the radical polymerizable monomer containing an aldo group and / or keto group, for example, diacetone (meth) acrylamide, vinyl alkyl ketones having 4 to 7 carbon atoms (for example, vinyl methyl ketone, vinyl ethyl ketone, Vinyl-n-propyl ketone, vinyl-i-propyl ketone, vinyl-n-butyl ketone,
Vinyl-i-butyl ketone, vinyl-t-butyl ketone, etc.), vinyl phenyl ketone, vinyl benzyl ketone, divinyl ketone, diacetone (meth) acrylylate, acetonitrile (meth) acrylylate, 2-
Hydroxypropyl (meth) acrylyl acetylacetate, 3-hydroxypropyl (meth) acrylylyl acetylacetate, 2-hydroxybutyl (meth) acrylylyl acetylacetate, 3
-Hydroxybutyl (meth) acrylic acid acetyl acetate, 4-hydroxybutyl (meth) acrylic acid acetyl acetate, butanediol-1,
4- (meth) acrylylate-acetylacetate and the like can be mentioned. Examples of the cross-linking agent having two or more hydrazide groups include oxalic acid dihydrazide, malonic acid dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, sebacine dihydrazide, phthalic acid dihydrazide, isophthalic acid dihydrazide, terephthalic acid dihydrazide. , Maleic acid dihydrazide, fumaric acid dihydrazide, itaconic acid dihydrazide, and the like, dicarboxylic acid dihydrazides having a total carbon number of 2 to 10, especially 4 to 6; citric acid trihydrazide, nitriloacetic acid trihydrazide, cyclohexanetricarboxylic acid trihydrazide, ethylenediamine tetra Trifunctional or higher functional hydrazides such as acetic acid tetrahydrazide; ethylene-1,
2-dihydrazine, propylene-1,2-dihydrazine, propylene-1,3-hydrazine, butylene-1,
3-dihydrazine, butylene-1,4-dihydrazine,
The total carbon number of butylene-2,3-dihydrazine is 2
~ 4 water-soluble dihydrazines such as aliphatic dihydrazines, and at least some of the hydrazino groups of these polyfunctional hydrazine derivatives, acetaldehyde, propionaldehyde, butyraldehyde, acetone, methyl ethyl ketone, diethyl ketone, methyl-n -A compound blocked by reacting with a carbonyl compound such as propyl ketone, methyl-n-butyl ketone and diacetone alcohol (hereinafter referred to as a "blocked polyfunctional hydrazine derivative"), for example, adipic dihydrazide monoacetone hydrazone, adipic acid Examples thereof include dihydrazide diacetone hydrazone. The amount of the crosslinking agent added is equimolar to 0.2 mol based on the total number of moles of the keto group and the aldo group. When such a coating material is used, it has excellent solvent resistance. Further, as the above coating material, it is also preferable to add a metal chelate compound acting as a silanol condensation catalyst before coating. Examples of the metal chelate compound include the organometallic compounds exemplified as the hydrolysis catalyst. The amount of the metal chelate compound added is 0.01 to 5% by weight in the aqueous dispersion (solid content conversion) of the present invention. When such a coating material is used, the curing time can be shortened.

As the constitution of the coated body of the present invention, for example,
On the base material, all those having a constitution in which a coating material containing the aqueous dispersion of the present invention is applied can be mentioned.
The following configurations are included. Base material (with or without primer treatment) / Clear or enamel base material (with or without primer treatment) of the water-based dispersion of the present invention (water-based dispersion alone or blend of water-based dispersion) Enamel of water-based dispersion of the invention (water-based dispersion alone, blend of water-based dispersion and other resin) / clear of water-based dispersion of the present invention (water-based dispersion alone, blend of water-based dispersion and other resin) Base material (with or without primer treatment) / clear other resin, or enamel / clear of water-based dispersion of the present invention (water-based dispersion alone, blend of water-based dispersion and other resin) or enamel

When a coating material (paint) containing the aqueous dispersion of the present invention is applied to a substrate, a brush, a roll coater, a flow coater, a centrifugal coater, an ultrasonic coater is used for any of the aqueous dispersions. , (Micro) gravure coater, etc., and dip coating, flow coating, spraying, screen process, electrodeposition and the like.

The aqueous dispersion of the present invention has a dry film thickness of
A coating film having a thickness of about 0.05 to 200 μm can be formed. Then, it is dried at room temperature or 30 ~
The coating film can be formed by heating at a temperature of about 200 ° C. and usually for about 1 to 60 minutes and drying.

When the undercoating of the aqueous dispersion of the present invention or another coating material is applied in advance, the dry film thickness is about 0.05 to 20 μm per coating,
By coating once, a coating film having a thickness of about 0.1 to 40 μm can be formed. After that, the coating film can be formed on various substrates by drying at room temperature or by heating at a temperature of about 30 to 200 ° C. for about 1 to 60 minutes and drying. The total film thickness of the undercoat and the topcoat is a dry film thickness of usually 0.1 to 400 μm, preferably about 0.2 to 300 μm.

Substrate Coating material (paint) containing the aqueous dispersion of the present invention
As a base material to which can be applied, polyethylene terephthalate (PET), polybutylene terephthalate (PB)
T), polyethylene-2,6-naphthalate (PEN)
Polyester such as: Polyamide such as nylon 6, nylon 6,6; Polyolefin such as polyethylene (PE), polypropylene (PP); Polycarbonate (P
C), polyacryl such as polymethylmethacrylate (PMMA); fluorine such as ABS resin, AES resin, polychlorinated biphenyl, polyvinyl alcohol, polyurethane, polyimide, polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE) In addition to plastic molded products such as resin and plastic films, organic base materials such as wood and paper; metal base materials such as iron, aluminum and stainless steel; cement, concrete, ALC, flexible board, mortar, slate, plaster, ceramics Inorganic ceramic base materials such as bricks.

These base materials may be subjected to surface treatment in advance for the purpose of adjusting the base, improving the adhesion, sealing the porous base material, smoothing, and patterning. For example, blast treatment, chemical treatment, degreasing, flame treatment, oxidation treatment, steam treatment, corona discharge treatment, ultraviolet irradiation treatment, plasma treatment, ion treatment and the like can be mentioned.

The coating specifications include the type and condition of the substrate,
It depends on the coating method. For example, in the case of a metal-based substrate,
If there is a need for rust prevention, an undercoat layer such as a primer or sealer may be provided, and in the case of inorganic ceramic base materials, the hiding property of the coating film may differ depending on the characteristics of the base material (surface roughness, impregnating property, alkalinity, etc.). Usually, a primer or sealer is used. Also in the case of an organic resin base material, a primer or a sealer is usually used. In the case of repainting a deteriorated coating film, if the old coating film is significantly deteriorated, a primer or sealer is used. In the case of other base materials, for example, metals that do not require rust prevention, tiles and glass, an undercoat layer may or may not be provided depending on the application.

As the undercoat layer, a primer not containing a filler, which is used for the purpose of ensuring adhesion with a substrate or a coating composition, rust prevention, eflation prevention, water penetration prevention, etc. And a sealer containing a filler, which is used for the purpose of imparting a design property to the appearance of the coating film. The types of the primer and sealer are not particularly limited, and can be selected according to the type of base material, purpose of use, and the like. The types of polymers used in the undercoat layer include, for example, alkyd resins, aminoalkyd resins,
Epoxy resin, polyester, acrylic resin, urethane resin, fluororesin, acrylic silicone resin, acrylic emulsion, epoxy emulsion, polyurethane emulsion, polyester emulsion, acrylic urethane emulsion, acrylic silicone emulsion, polysiloxane, other silicone-containing emulsion, etc. You can These polymers are preferably used by blending two or more kinds thereof, and the above-mentioned aqueous dispersion may be used as a component to be blended. Preferred primer combinations include acrylic emulsion / water-based dispersion, acrylic emulsion / epoxy emulsion, silicon-containing emulsion / epoxy emulsion, epoxy emulsion / acrylic urethane emulsion, acrylic silicone emulsion / epoxy emulsion / acrylic emulsion, and the like. Further, various functional groups can be added to these polymers when the adhesion between the base material and the coating film under severe conditions is required. As such a functional group,
For example, hydroxyl group, carboxyl group, carbonyl group, amide group, amine group, glycidyl group, alkoxysilyl group,
Examples thereof include an alkylsilyl group, an ether bond and an ester bond. Further, a curing accelerator may be added to the resin used for the undercoat layer. The compounds exemplified as the (E) hydrolysis catalyst (curing accelerator) used as an optional component of the above-mentioned aqueous dispersion may be used for the acrylic resin, urethane resin, etc. Epoxy curing agents such as amines, imidazole derivatives, acid anhydrides and polyamide resins are used.

The surface of a coating film formed from the aqueous dispersion of the present invention may be, for example, US Pat. No. 3,986,99 for the purpose of further enhancing the abrasion resistance and gloss of the coating film.
It is also possible to form a clear layer composed of a siloxane resin-based paint such as a stable dispersion of colloidal silica and a siloxane resin described in US Pat. No. 7, U.S. Pat. No. 4,027,073 and the like. .

[0100]

EXAMPLES The embodiments of the present invention will be described more specifically below with reference to examples. However, the present invention is not limited to these examples. In addition, various measurements and evaluations in Examples and Comparative Examples were performed by the following methods.

(1) Weather resistance According to JIS K5400, an irradiation test was carried out with a sunshine weather meter for 6,000 hours, and the appearance (cracks, peeling, etc.) of the coating film was visually observed. Those that did not change were marked as "○". (2) Adhesiveness Cross-cut test according to JIS K5400 (Measure 100
The tape peeling test was performed 3 times, and based on the average, the case where the number of peeled cells was 1 or less was marked as "○". (3) After coating the coating with a blocking resistance coating, heating and drying, leave it to cool to 45 ° C
After the surface temperature was lowered to 2, the coated bodies were immediately placed in a constant temperature bath at 45 ° C. with the coated surfaces being overlapped with each other and placed horizontally, and a weight was placed on the coated body so that the weight became 3 kg / cm 2 and stored. After 24 hours, take it out and let it cool down to 25
The temperature of the base material was lowered to ℃, and the case where the two coated bodies were peeled off by hand and the surface condition was not changed was rated as "◯". (4) Freezing damage resistance According to JIS A6909, a hot and cold repeated test was carried out, and the appearance (cracks, peeling, etc.) of the coating film was visually observed. Those that did not change were marked as "○"

Examples (1) to (4) Each component shown in Table 1 was emulsified with stirring at room temperature for 10 minutes, an acidic component was added thereto, and hydrolysis / condensation reaction was carried out at 40 ° C. for 2 hours while continuing stirring. After that, the mixture was emulsified with a high pressure homogenizer [Microfluidizer M110Y manufactured by Mizuho Industry Co., Ltd.] at a pressure of 70 MPa. This emulsion was placed in a separable flask and, while stirring, the atmosphere was replaced with nitrogen, then a radical initiator (potassium persulfate aqueous solution) was added, and the mixture was stirred at 4 ° C at 75 ° C.
Polymerized for hours. After the polymerization, the pH of the system was adjusted to 7.0 using an aqueous ammonia solution. The polymerization results are also shown in Table 1.

[0103]

[Table 1]

TINUVIN-123; manufactured by Ciba Geigy, hindered amine light stabilizer LA-82; manufactured by Asahi Denka Co., Ltd., reactive hindered amine light stabilizer X40-9220; manufactured by Shin-Etsu Chemical Co., Ltd., methyltrimethoxy SH6018, a hydrolyzed condensate of 10 to 15 molecules of silane; manufactured by Toray Dow Corning Silicone Co., Ltd., a complete hydrolyzed condensate of methyltrimethoxysilane and phenyltrimethoxysilane PE-200; manufactured by NOF Corporation, Bremmer PE-2
00, polyoxyethylene methacrylate

Using the water-based polymer dispersions (1) to (4) obtained in Examples (1) to (4), 100 parts by weight of this water-based polymer dispersion was used, as shown in Table 1, as necessary. Accordingly, adipic acid dihydrazide (10 wt% aqueous solution) and dibutyltin dilaurate (10 wt% aqueous dispersion) were added and mixed to prepare a coating agent (clear).
Silicon acrylic emulsion B73 manufactured by JSR Corporation
White enamel with 02 as varnish (PWC = 40%) was applied at a dry weight of 50 g / m ² dry to an aluminum plate, and the obtained coating agent was applied at a dry weight of 25 g / m ² dry, and the temperature was adjusted to 4 at 140 ° C.
It heated for a minute and produced the test piece. Various evaluations were performed on the obtained test pieces. The evaluation results are shown in Table 1.

Comparative Example (1) (Example of Polymerization by Normal Emulsion Polymerization Instead of Miniemulsion) The components shown in Table 2 were mixed, and 30% by weight of this monomer mixture was put into a separable flask and stirred. However, after substitution with nitrogen, a radical polymerization initiator (potassium persulfate aqueous solution) was added, and polymerization was carried out at 75 ° C. for 1 hour. Subsequently, the remaining monomer mixture and the component (C ′) shown in Table 1 were made to flow from separate dropping tanks for 2 hours. At 30 minutes after the inflow, aggregates began to be visually generated, and at the end of the inflow, the entire separable flask was solidified into a gel. Comparative Examples (2) to (4) The components shown in Table 2 were mixed and polymerized and evaluated in the same manner as in Examples. The results are shown in Table 2.

[0107]

[Table 2]

[0108]

The water-based dispersion of the present invention is excellent in weather resistance / adhesion balance and blocking resistance / freezing resistance balance, which have not been obtained by a conventionally known method, and is useful as a water-based coating agent.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C08F 290/06 C08F 290/06 299/02 299/02 C08L 83/04 C08L 83/04 C09D 5/02 C09D 5/02 133/00 133/00 151/08 151/08 183/04 183/04 (72) Inventor Kenji Ishizuke 2-11-24 Tsukiji, Chuo-ku, Tokyo J-SR Co., Ltd. F-term (reference) 4J002 BG01W BG04W BG05W BG06W BG07W BG08W CD19W CP03X CP06X CP08X CP09X CP14X HA07 4J011 KA04 KA05 KA09 KA13 KA15 PA99 PC02 4J026 AB44 BA03 BA06 DB02 CB1 CA01 BA06 BA02 BA04 BA14 BA14 BA13 BA14 BA13 BA14 BA13 BA06 BA04 BA13 BA06 BA04 BA06 BA04 BA06 BA04 BA13 CH042 CH051 CH052 CH071 CH072 CH121 CH122 CH201 CH202 CH251 CH252 CJ031 CJ032 CJ041 CJ042 CJ131 CJ132 CJ141 CJ142 DL021 DL022 DL031 DL032 DL051 DL052 DL071 DL 072 DL081 DL082 DL091 DL092 DL121 DL122 KA04 KA08 KA12 LA02 MA13 MA14 NA03 NA04 NA11 NA12 NA26

Claims (6)

[Claims] 1. In an aqueous medium, (A) the following general formula (1) (R ¹ ) _4-n- (Si)-(OR ² ) _n ... (1) (wherein R ¹ is the same. Alternatively, a hydrogen atom, a phenyl group or a monovalent organic group having 1 to 8 carbon atoms, R ² are the same or different, and a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or an acyl group having 1 to 6 carbon atoms, n Is an integer of 2 to 4.)
5 to 80 parts by weight of a polyorganosiloxane (calculated as a complete hydrolyzed condensate) obtained from at least one selected from the group consisting of organosilanes represented by: , And (B) 95 to 20 parts by weight of an acrylic polymer having a glass transition point of −20 ° C. to 80 ° C. [where (A) + (B) = 1
00 parts by weight], and n of the general formula (1) constituting the component (A) (completely hydrolyzed condensate) and the component (A) satisfies the following formula (2): An aqueous dispersion in which polyorganosiloxane / acrylic polymer composite particles are dispersed. (−0.005x + 2.6) ≦ n ≦ (−0.005x + 3.3) (2) 2. In an aqueous medium, at least one selected from the group consisting of (A ′) an organosilane represented by the general formula (1), a hydrolyzate thereof and a condensate thereof, (B ′) above ( B) A radical-polymerizable monomer component containing an acrylic monomer that constitutes an acrylic polymer, and (C) an emulsifier were mixed to form an emulsion, and hydrolysis and condensation of the component (A ′) were promoted. After that, the average particle diameter of the emulsion is refined to 0.5 μm or less, and then (D) a radical polymerization initiator is added, and (B ′) a monomer component is radically polymerized to obtain the emulsion. Aqueous dispersion. 3. The (B ′) monomer component is a radically polymerizable monomer having a dialkylamide group, a radically polymerizable monomer having a dialkylamino group, and a radically polymerizable compound having a polyoxyethylene group. The aqueous dispersion according to claim 2, containing at least one selected from the group of monomers. 4. The aqueous dispersion according to claim 2 or 3, which comprises a reactive emulsifier having a polyoxyethylene chain as the (C) emulsifier. 5. The aqueous dispersion according to any one of claims 2 to 4, wherein (E) a light stabilizer substantially insoluble in water is further present during emulsification. 6. In emulsification, the weight average molecular weight of (F) polystyrene conversion is 1,000 to 10,
000 poly (meth) acrylate is present, The aqueous dispersion according to any one of claims 2 to 5.