JP5521306B2 - Curable aqueous composition - Google Patents

Description

  The present invention relates to a curable aqueous composition suitable for a resin for exterior wall coating, having a low low temperature curing rate, a long pot life, and excellent weather resistance and low contamination.

  A water-based resin capable of reducing volatile solvents is used as an outdoor coating resin for building exterior walls in order to reduce the environmental load. In addition, coatings are required to have high weather resistance and low contamination for the purpose of extending the life of buildings. An example of a coating resin that satisfies these requirements is a polysiloxane of a composite resin (AB) in which a polymer segment (A) having a neutralized acid group and a polysiloxane segment (B) are chemically bonded. Composite resin in which segment (B) and polysiloxane segment (C) derived from condensate (c) of alkyltrialkoxysilane having 1 to 3 carbon atoms in the alkyl group are bonded via a silicon-oxygen bond ( An example using an aqueous product of a composite resin (ABC) obtained by dissolving or dispersing (ABC) in an aqueous medium has been proposed (for example, see Patent Document 1).

However, in the above method, a curing agent (for example, 3-glycidoxypropyltrimethoxysilane) is mixed and used for use. However, the epoxy group in the curing agent and the carboxyl group of the composite resin (ABC) A certain time is required for the reaction and the curing speed is slow.
In particular, when used in outdoor coating applications where sufficient heating is not possible, there is a problem of poor water resistance when the coating surface gets wet due to condensation at night when the curing speed is slow. In such a case, the above-described literatures describe a method of using various curing agents for the main resin.
However, in use in outdoor coating as described above, when the construction temperature is low, the curing rate becomes slow and a long time is required for curing, and the above-mentioned difficulties cannot be improved.
In order to improve this, it is considered to use a large amount of a curing agent or to use a highly active curing agent. There is a problem that the life is shortened and workability such as workability is inferior.

JP 2008-106228 A

  The problem to be solved by the present invention is to provide a curable aqueous composition that, when used as a coating agent, has a low low-temperature curing rate, a long pot life, and excellent weather resistance and low contamination.

  The problem to be solved by the present invention is to provide a curable aqueous composition that is excellent in low-temperature curing speed even when used as a coating agent in outdoor coating applications where sufficient heating is not possible. .

  As a result of intensive studies to solve the above problems, the present inventor has obtained a composite resin in which a polymer segment (A) having a neutralized acid group and a polysiloxane segment (B) are chemically bonded. The polysiloxane segment (B) of (AB) and the polysiloxane segment (C) derived from the condensate (c) of alkyltrialkoxysilane having an alkyl group having 1 to 3 carbon atoms are bonded via a silicon-oxygen bond. The present invention has been completed by finding that a composite resin in which the following structure is bonded to the composite resin (ABC) is capable of solving the above-mentioned problems.

  That is, the present invention relates to a polysiloxane segment (B) of a composite resin (AB) formed by chemically bonding a polymer segment (A) having a neutralized acid group and a polysiloxane segment (B), and an alkyl group. A composite resin (ABC) in which a polysiloxane segment (C) derived from a condensate (c) of an alkyltrialkoxysilane having 1 to 3 carbon atoms is bonded via a silicon-oxygen bond is present in an aqueous medium. A curable aqueous composition containing an aqueous solution of a composite resin (ABC) that is dissolved or dispersed, wherein the composite resin (ABC) has the following general formulas (1-1), (1-2), and ( Provided is a curable aqueous composition characterized by containing at least one type of structure represented by 1-3).

(In the formula, m and n each independently represent 1 to 4 repeating units, k represents 4 to 12 repeating units, and X ¹ and X ² each independently represent a hydroxyl group, a methoxy group, or an ethoxy group. Represents a propoxy group and a butoxy group, and X ³ represents a hydroxyl group, a methyl group, a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.)

  When the curable aqueous composition of the present invention is used as a resin for coating building exterior walls, the low-temperature curing rate is high, the pot life is long, and good workability can be obtained.

  Below, the curable aqueous composition of this invention is demonstrated concretely.

  The composite resin (ABC) used in the present invention is, for example, a composite resin (AB) formed by chemically bonding a polymer segment (A) having a neutralized acid group and a polysiloxane segment (B). The polysiloxane segment (B) and the polysiloxane segment (C) derived from the condensate (c) of alkyltrialkoxysilane having 1 to 3 carbon atoms in the alkyl group are bonded via a silicon-oxygen bond. Any composite resin may be used. For example, the composite resin having a graft structure in which the polysiloxane segment (B) is chemically bonded to the side chain of the polymer segment (A) having a neutralized acid group, or the polymer A polysiloxane segment (B) of a composite resin having a block structure in which the polysiloxane segment (B) is chemically bonded to the terminal of the segment (A), and an alkyl group General examples of the composite resin having a structure in which the polysiloxane segment (C) derived from the condensate (c) of alkyltrialkoxysilane having 1 to 3 carbon atoms is chemically bonded through a silicon-oxygen bond are mentioned above. It contains the structures of formulas (1-1), (1-2) and (1-3).

  As a method for introducing the structures of the general formulas (1-1), (1-2), and (1-3), for example, the composite resin (ABC) and an organoalkoxysilane containing an epoxy group are described below. It is obtained by making it react with the manufacturing method to do.

  Examples of the organoalkoxysilane include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropyltributoxysilane, γ-glycidoxypropyltriisopropoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane , Β- (3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, β- (3,4-epoxycyclohexyl) ethylmethyldiethoxysilane, 5,6-epoxyhexyltrimethoxysilane, 9,10-epoxydecyltrimethoxy Syrah Etc., and among these, trialkoxysilanes are preferred.

  The chemical bond between the polymer segment (A) and the polysiloxane segment (B) included in the composite resin (ABC) is not particularly limited. For example, the following structural formula (S-1) or Examples include the bonding mode of the following structural formula (S-2). Among them, the use of a composite resin having the bonding mode of the structural formula (S-1) can form a coating film excellent in weather resistance. preferable. [However, the carbon atom in the structural formula (S-1) constitutes a part of the polymer segment (A), and the silicon atom and the oxygen atom constitute a part of the polysiloxane segment (B). ]

  [However, the carbon atom in the structural formula (S-2) constitutes a part of the polymer segment (A), and the silicon atom constitutes a part of the polysiloxane segment (B). ]

  The polymer segment (A) constituting the composite resin (ABC) may be a polymer segment having a neutralized acid group in order to disperse or dissolve the composite resin (ABC) in an aqueous medium. Essentially, among them, the above structural formula (S-1) is easily hydrolyzed and condensed with a hydroxyl group bonded to a silicon atom or a hydrolyzable group bonded to a silicon atom of the polysiloxane segment (B) or its synthesis raw material. Therefore, a hydroxyl group bonded to a silicon atom and / or a hydrolyzable group bonded to a silicon atom (hereinafter referred to as “hydroxyl group and / or hydrolyzable group of a silicon atom bond”) together with an acid group. It is preferably a polymer segment derived from the polymer (a ′) having abbreviated) or the polymer (a) which is a neutralized product thereof. The polymer (a ′) and the polymer (a) may be any polymer other than polysiloxane having an acid group or a neutralized acid group. Examples of the polymer include an acrylic polymer and a fluoroolefin. Examples thereof include vinyl polymers such as polymers, vinyl ester polymers, aromatic vinyl polymers, and polyolefin polymers, polyurethane polymers, polyester polymers, polyether polymers, among others, vinyl polymers and A polyurethane polymer is preferred, and an acrylic polymer is more preferred.

  Examples of the acid group in the polymer (a ′) include a carboxyl group, a phosphoric acid group, an acidic phosphoric acid ester group, a phosphorous acid group, a sulfonic acid group, and a sulfinic acid group. Among them, a composite resin (ABC) A carboxyl group is preferable because it can be easily introduced into the skeleton.

  Examples of the basic compound used for neutralizing the acid group include organic amines such as methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, 2-aminoethanol, and 2-dimethylaminoethanol. ; Inorganic basic compounds such as ammonia, sodium hydroxide and potassium hydroxide; quaternary ammonium hydroxides such as tetramethylammonium hydroxide, tetra-n-butylammonium hydroxide and trimethylbenzylammonium hydroxide can be used. Of these, organic amines and ammonia (ammonia water may be used) are preferably used.

  From the viewpoint of maintaining good storage stability of an aqueous dispersion or aqueous solution in which the composite resin (ABC) is dispersed or dissolved in an aqueous medium, the neutralized acid group in the polymer (a). It is preferably present at a rate of 0.1 to 20% by weight, more preferably at a rate of 0.2 to 10% by weight, based on 100% by weight of the composite resin (ABC). preferable.

  The hydrolyzable group bonded to the silicon atom in the polymer (a ′) may be a functional group capable of generating a hydroxyl group bonded to the silicon atom (silanol group) by hydrolysis. For example, halogen atoms bonded to silicon atoms, alkoxy groups bonded to silicon atoms, acyloxy groups bonded to silicon atoms, phenoxy groups bonded to silicon atoms, mercapto groups bonded to silicon atoms, bonded to silicon atoms Examples include amino groups, amide groups bonded to silicon atoms, aminooxy groups bonded to silicon atoms, iminooxy groups bonded to silicon atoms, and alkenyloxy groups bonded to silicon atoms, among which hydrolysis proceeds easily. In addition, an alkoxy group bonded to a silicon atom is preferable because a by-product after the reaction can be easily removed.

  The polymer segment (A) has other functional groups excluding neutralized acid groups, hydroxyl groups bonded to silicon atoms, and hydrolyzable groups bonded to silicon atoms, as long as the effects of the present invention are not impaired. You may have. Examples of such other functional groups include unneutralized carboxyl groups, blocked carboxyl groups, carboxylic anhydride groups, hydroxyl groups, blocked hydroxyl groups, cyclocarbonate groups, epoxy groups, carbonyl groups, and primary amide groups. Secondary amide group, carbamate group, polyethylene glycol group, polypropylene glycol group, group shown by following structural formula (S-3), etc. are mentioned.

  Examples of the polysiloxane segment (B) constituting the composite resin (ABC) include a segment derived from a polysiloxane having a silicon atom-bonded hydroxyl group and / or a hydrolyzable group. Examples of the hydrolyzable group bonded to the silicon atom include those similar to the hydrolyzable group bonded to the silicon atom described in the polymer segment (A), and preferred ones are also the same.

  As said polysiloxane segment (B), what has the structure shown by the following general formula (S-4) or (S-5) is preferable. Since the polysiloxane segment having the structure represented by the following general formula (S-4) or (S-5) has a three-dimensional network polysiloxane structure, the resulting coating film is excellent in weather resistance and the like. It is a thing.

[In the general formulas (S-4) and (S-5), R ¹ is an organic group having 4 to 12 carbon atoms bonded to a silicon atom, and R ² and R ³ are each independently a silicon atom. A bonded methyl group or an ethyl group bonded to a silicon atom. R ¹ is preferably a hydrocarbon group having 4 to 12 carbon atoms bonded to a silicon atom, and more preferably a phenyl group or an alkyl group having 4 carbon atoms. R ² and R ³ are each preferably a methyl group bonded to a silicon atom or an ethyl group bonded to a silicon atom, and more preferably a methyl group bonded to a silicon atom. ]

  The polysiloxane segment having the structure represented by the general formula (S-4) or (S-5) is an organoalkoxysilane, preferably an organic group having 4 to 12 carbon atoms bonded to a silicon atom (hereinafter, “ A monoorganotrialkoxysilane having a silicon atom-bonded organic group having 4 to 12 carbon atoms ”) and / or a methyl group bonded to a silicon atom and / or an ethyl group bonded to a silicon atom (hereinafter referred to as an“ organic group ”). And a segment derived from polysiloxane obtained by hydrolytic condensation of a diorganodialkoxysilane having two of “a silicon atom-bonded methyl group and / or ethyl group”. These polysiloxane segments consist of two organic atom-bonded organic groups having 4 to 12 carbon atoms, silicon atom-bonded hydroxyl groups and / or hydrolyzable groups, and / or silicon atom-bonded methyl groups and / or ethyl groups. And a silicon atom-bonded hydroxyl group and / or hydrolyzable group, and may have any structure of linear, branched, and cyclic.

  Examples of the organic group having 4 to 12 carbon atoms bonded to the silicon atom include an alkyl group, a cycloalkyl group, an aryl group, and an aralkyl group each having 4 to 12 carbon atoms bonded to the silicon atom. In addition, these organic groups may have a substituent.

  Such an organic group having 4 to 12 carbon atoms bonded to a silicon atom is preferably a hydrocarbon group bonded to a silicon atom, for example, an n-butyl group, an iso-butyl group, or an n-hexyl bonded to a silicon atom. Group, n-octyl group, n-dodecyl group, alkyl group such as cyclohexylmethyl group; cycloalkyl group such as cyclohexyl group, 4-methylcyclohexyl group; aryl group such as phenyl group, 4-methylphenyl group; benzyl group, etc. Among them, a phenyl group bonded to a silicon atom or an alkyl group having 4 carbon atoms bonded to a silicon atom is more preferable.

  The polysiloxane segment (C) constituting the composite resin (ABC) is a segment derived from a condensate (c) of an alkyltrialkoxysilane having 1 to 3 carbon atoms in the alkyl group, and the alkyl group used here The alkyltrialkoxysilane condensate (c) having 1 to 3 carbon atoms has a hydroxyl group bonded to a silicon atom and / or an alkoxy group bonded to a silicon atom.

  The alkyltrialkoxysilane condensate (c) preferably has a structure represented by the following general formula (S-6). Since the polysiloxane segment derived from the alkyltrialkoxysilane condensate having the structure represented by the following general formula (S-6) has a three-dimensional network-like polysiloxane structure, the resulting coating film has weather resistance. It is an excellent one.

[However, R ⁴ in the general formula (S-6) is an alkyl group having 1 to 3 carbon atoms. ]

  As the composite resin (ABC), since a coating film having excellent weather resistance is obtained, a polysiloxane segment (B) and an alkyltrialkoxysilane condensate (100 parts by weight of the composite resin (ABC)) ( The polysiloxane segment (C) derived from c) and the total amount (B + C) are preferably 15 to 85 parts by weight, more preferably 25 to 85 parts by weight.

  In addition, as the composite resin (ABC), since a coating film having excellent durability and crack resistance is obtained, the alkyltrialkoxysilane condensate (100 parts by weight of the composite resin (ABC)) ( The amount of the polysiloxane segment (C) derived from c) is preferably 15 to 60 parts by weight, and more preferably 30 to 60 parts by weight.

  Although the said composite resin (ABC) can be manufactured with various methods, it is preferable to manufacture in the process which consists of the following manufacturing process (I)-(II) especially.

Step (I)
(I) A polymer (a ′) having both an acid group and a silicon atom-bonded hydroxyl group and / or hydrolyzable group, and an organoalkoxysilane (b) and / or a hydrolysis condensate thereof (b-1). Composite resin (A'B) formed by chemical condensation of polymer segment (A ') derived from polymer (a') and polysiloxane segment (B) derived from organoalkoxysilane (b) by hydrolytic condensation It is the process of obtaining.

Step (II)
(II) Next, the resulting composite resin (A′B) and the alkyltrialkoxysilane condensate (c) having 1 to 3 carbon atoms in the alkyl group are hydrolytically condensed to give the composite resin (A′B). The polysiloxane segment (B) and the polysiloxane segment (C) derived from the condensate (c) of alkyltrialkoxysilane having 1 to 3 carbon atoms in the alkyl group are bonded via a silicon-oxygen bond. A step of obtaining a composite resin (ABC) by neutralizing acid groups in the composite resin (A'BC) with a basic compound after the composite resin (A'BC) is obtained, or the obtained composite resin (A'BC) After the acid group in ′ B) is neutralized with a basic compound to form a composite resin (AB), the condensation product (c) of alkyltrialkoxysilane having 1 to 3 carbon atoms in the alkyl group is hydrolyzed and condensed. Polysiloxane segment of composite resin (AB) Composite resin (B) and a polysiloxane segment (C) derived from a condensate (c) of alkyltrialkoxysilane having 1 to 3 carbon atoms of an alkyl group bonded via a silicon-oxygen bond ( ABC).

  The hydrolysis-condensation reaction in the production process can be progressed by various methods, but a method in which the reaction is advanced by supplying water and a catalyst during the production process is simple and preferable.

  The hydrolysis condensation reaction refers to a condensation reaction in which part of the hydrolyzable group is hydrolyzed under the influence of water or the like to form a hydroxyl group, and then proceeds between the hydroxyl group or hydrolyzable group.

  The polymer (a ′) is a polymer having both an acid group and a silicon atom-bonded hydroxyl group and / or hydrolyzable group, and the neutralized acid except that the acid group is not neutralized. This is exactly the same as the polymer (a) having both a group and a silicon atom-bonded hydroxyl group and / or hydrolyzable group.

  When a vinyl polymer is used as the polymer (a ′), the vinyl polymer may be, for example, an acid group-containing vinyl monomer, a hydroxyl group-containing vinyl monomer bonded to a silicon atom, and / or a silicon atom. The polymer can be produced by polymerizing a hydrolyzable group-containing vinyl monomer bonded to, and if necessary, another vinyl monomer.

  The acid group-containing vinyl monomer contains a vinyl monomer containing a carboxyl group as an essential component, for example, a carboxylic acid anhydride group, a phosphoric acid group, an acidic phosphoric acid ester group, a phosphorous acid group, a sulfonic acid group, Various vinyl monomers containing acid groups such as sulfinic acid groups may be used in combination.

  Examples of the carboxyl group-containing vinyl monomer include (meth) acrylic acid, 2-carboxyethyl (meth) acrylate, crotonic acid, itaconic acid, maleic acid, fumaric acid and other unsaturated carboxylic acids; maleic anhydride, Unsaturated polycarboxylic acid anhydrides such as itaconic anhydride; unsaturated monocarboxylic acid anhydrides such as acrylic acid anhydride and methacrylic anhydride; unsaturated carboxylic acid such as acrylic acid and methacrylic acid; acetic acid and propion Acid, mixed acid anhydride with saturated carboxylic acid such as benzoic acid; monomethyl itaconate, mono-n-butyl itaconate, monomethyl maleate, mono-n-butyl maleate, monomethyl fumarate, mono-n-fumarate Various monoesters (half-esters) of saturated dicarboxylic acids such as butyl and saturated monohydric alcohols; Monovinyl esters of saturated dicarboxylic acids such as monovinyl dipinate and monovinyl succinate; bonded to carbon atoms with anhydrides of saturated polycarboxylic acids such as succinic anhydride, glutaric anhydride, phthalic anhydride and trimellitic anhydride Addition reaction products with vinyl monomers containing hydroxyl groups; and various monomers obtained by addition reaction of the carboxyl group-containing monomers with lactones, among others. Unsaturated carboxylic acids such as (meth) acrylic acid are preferred because they can be easily introduced into the vinyl polymer.

  The carboxyl group may be blocked. Examples of the vinyl monomer having a blocked carboxyl group include trimethylsilyl (meth) acrylate, dimethyl-tert-butylsilyl (meth) acrylate, and trimethylsilylcroto. Silyl ester group-containing vinyl monomers such as nates; hemiacetal ester groups such as 1-ethoxyethyl (meth) acrylate, 2-methoxy-2- (meth) acryloyloxypropane, 2- (meth) acryloyloxytetrahydrofuran Or hemiketal ester group-containing monomers; tert-butyl ester group-containing monomers such as tert-butyl (meth) acrylate and tert-butyl crotonate.

  Examples of the hydroxyl group-containing vinyl monomer bonded to the silicon atom include trihydroxyvinylsilane, ethoxydihydroxyvinylsilane, diethoxyhydroxyvinylsilane, dichlorohydroxyvinylsilane, 3- (meth) acryloyloxypropyltrihydroxysilane, 3 -(Meth) acryloyloxypropylmethyldihydroxysilane and the like.

  As the hydrolyzable group-containing vinyl monomer bonded to the silicon atom, for example, a vinyl monomer having a hydrolyzable group represented by the following general formula (S-7) can be used.

[In the general formula (S-7), R ⁵ represents a monovalent organic group such as an alkyl group, an aryl group or an aralkyl group, and R ⁶ represents a halogen atom, an alkoxy group, an acyloxy group, a phenoxy group or an aryloxy group. , A mercapto group, an amino group, an amide group, an aminooxy group, an iminooxy group, or an alkenyloxy group, and b is an integer of 0-2. ]

  Examples of the vinyl monomer having a hydrolyzable group represented by the general formula (S-7) include vinyltrimethoxysilane, vinyltriethoxysilane, vinylmethyldimethoxysilane, vinyltri (2-methoxyethoxy) silane, and vinyl. Triacetoxysilane, vinyltrichlorosilane, 2-trimethoxysilylethyl vinyl ether, 3- (meth) acryloyloxypropyltrimethoxysilane, 3- (meth) acryloyloxypropyltriethoxysilane, 3- (meth) acryloyloxypropylmethyldimethoxy Silane, 3- (meth) acryloyloxypropyltrichlorosilane, and the like. Among them, the hydrolysis reaction can easily proceed, and by-products after the reaction can be easily removed. Silane, 3 (Meth) acryloyloxy propyl trimethoxy silane is preferred.

  Examples of the other vinyl monomers include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, tert- Alkyl (meth) acrylates having an alkyl group having 1 to 22 carbon atoms such as butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate; benzyl (meth) acrylate, 2-phenylethyl (meta ) Aralkyl (meth) acrylates such as acrylate; Cycloalkyl (meth) acrylates such as cyclohexyl (meth) acrylate and isobornyl (meth) acrylate; 2-methoxyethyl (meth) acrylate, 4-methoxybutyl (meth) acrylic Ω-alkoxyalkyl (meth) acrylates such as carbonates; aromatic vinyl monomers such as styrene, p-tert-butylstyrene, α-methylstyrene, vinyltoluene; vinyl acetate, vinyl propionate, pivalic acid Carboxylic acid vinyl esters such as vinyl and vinyl benzoate; alkyl esters of crotonic acid such as methyl crotonate and ethyl crotonate; Unsaturation such as dimethyl malate, di-n-butyl malate, dimethyl fumarate and dimethyl itaconate Dialkyl esters of dibasic acids; α-olefins such as ethylene and propylene; fluoroolefins such as vinylidene fluoride, tetrafluoroethylene, hexafluoropropylene and chlorotrifluoroethylene; alkyls such as ethyl vinyl ether and n-butyl vinyl ether Nyl ethers; Cycloalkyl vinyl ethers such as cyclopentyl vinyl ether and cyclohexyl vinyl ether; Tertiary amides such as N, N-dimethyl (meth) acrylamide, N- (meth) acryloylmorpholine, N- (meth) acryloylpyrrolidine and N-vinylpyrrolidone Group-containing monomers;

Hydroxyalkyl (meth) acrylates such as 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and 4-hydroxybutyl (meth) acrylate; hydroxyl groups such as 2-hydroxyethyl vinyl ether and 4-hydroxybutyl vinyl ether -Containing vinyl ethers; hydroxyl group-containing allyl ethers such as 2-hydroxyethyl allyl ether and 2-hydroxybutyl allyl ether; vinyl monomers containing hydroxyl groups bonded to these carbon atoms and lactones such as ε-caprolactone; Addition reaction product of

2-dimethylaminoethyl (meth) acrylate, 2-diethylaminoethyl (meth) acrylate, 2-di-n-propylaminoethyl (meth) acrylate, 3-dimethylaminopropyl (meth) acrylate, 4-dimethylaminobutyl (meth) ) Tertiary amino group-containing (meth) acrylic acid esters such as acrylate and N- [2- (meth) acryloyloxy] ethylmorpholine; tertiary amino group-containing vinylpyridine, N-vinylcarbazole, N-vinylquinoline, etc. Aromatic vinyl monomers: N- (2-dimethylamino) ethyl (meth) acrylamide, N- (2-diethylamino) ethyl (meth) acrylamide, N- (2-di-n-propylamino) ethyl ( Tertiary amino group-containing (meth) acrylamides such as (meth) acrylamide; Tertiary amino group-containing crotonic acid amides such as-(2-dimethylamino) ethylcrotonic acid amide, N- (4-dimethylamino) butylcrotonic acid amide; 2-dimethylaminoethyl vinyl ether, 2-diethylaminoethyl vinyl ether, 4 -Tertiary amino group-containing vinyl ethers such as dimethylaminobutyl vinyl ether.

  The type and amount of the other vinyl monomer can be appropriately selected in accordance with the properties imparted to the curable aqueous composition of the present invention as long as the effects exhibited by the present invention are not impaired.

  The polymer (a ′) is selected from the group consisting of an anionic group, a cationic group and a nonionic group for the purpose of improving the solubility or dispersibility of the composite resin (ABC) in an aqueous medium. Those having at least one hydrophilic group can be used.

  Examples of the vinyl polymer usable as the polymer (a ′) include acid group-containing vinyl monomers, hydroxyl group-containing vinyl monomers bonded to silicon atoms, and / or hydrolyzable bonded to silicon atoms. It can be produced by polymerizing a group-containing vinyl monomer and, if necessary, another vinyl monomer by a polymerization method such as a bulk radical polymerization method, a solution radical polymerization method or a non-aqueous dispersion radical polymerization method. Especially, since it is easy to manufacture, it is preferable to apply a so-called solution radical polymerization method in which a vinyl polymer is manufactured by radical polymerization of the vinyl monomer in an organic solvent.

  When the vinyl monomer is polymerized by the radical polymerization method, a polymerization initiator can be used as necessary. Examples of such polymerization initiators include 2,2'-azobis (isobutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2,2'-azobis (2-methylbutyronitrile). Azo compounds such as nitrile); tert-butyl peroxypivalate, tert-butyl peroxybenzoate, tert-butyl peroxy-2-ethylhexanoate, di-tert-butyl peroxide, cumene hydroperoxide, diisopropyl And peroxides such as peroxycarbonate.

  Examples of the organic solvent include aliphatic or alicyclic hydrocarbons such as n-hexane, n-heptane, n-octane, cyclohexane, and cyclopentane; aromatic hydrocarbons such as toluene, xylene, and ethylbenzene. Alcohols such as methanol, ethanol, n-butanol, ethylene glycol monomethyl ether, propylene glycol monomethyl ether; ethyl acetate, n-butyl acetate, n-amyl acetate, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate Esters such as acetone; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl n-amyl ketone, cyclohexanone; diethylene glycol dimethyl ether, diethylene glycol dibutyl ether Polyalkylene glycol dialkyl ethers such as 1, ethers such as 1,2-dimethoxyethane, tetrahydrofuran, and dioxane; N-methylpyrrolidone, dimethylformamide, dimethylacetamide, ethylene carbonate, and the like. These may be used alone or in combination of two or more. Can be used in combination.

  The polymer (a ') preferably has a number average molecular weight in the range of 500 to 200,000, more preferably in the range of 700 to 100,000, and in the range of 1,000 to 50,000. Particularly preferred are those having By using the polymer (a ′) having a number average molecular weight within such a range, it is possible to prevent thickening and gelation when producing the composite resin (ABC), and to provide a coating film excellent in durability. Can be formed.

  Next, the organoalkoxysilane (b) and / or the hydrolysis condensate (b-1) thereof used for constituting the polysiloxane segment (B) in the production step (I) will be described.

  The organoalkoxysilane (b) is not particularly limited, and among them, a composite resin (ABC) having excellent dispersion stability can be produced, and a coating film having excellent durability can be formed. A monoorganotrialkoxysilane having an organic group having 4 to 12 carbon atoms and a diorganodialkoxysilane having two methyl groups and / or ethyl groups are preferred.

  The hydrolysis-condensation product (b-1) of the organoalkoxysilane (b) is not particularly limited as long as it is a hydrolysis-condensation product of the organoalkoxysilane (b). A monoorganotrialkoxysilane having ˜12 organic groups and / or a diorganodialkoxysilane having two silicon atom-bonded methyl and / or ethyl groups is preferably hydrolyzed and condensed.

  Examples of the monoorganotrialkoxysilane having a silicon atom-bonded organic group having 4 to 12 carbon atoms include iso-butyltrimethoxysilane, cyclohexyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, 3- ( And (meth) acryloyloxypropyltrimethoxysilane, 3- (meth) acryloyloxypropyltriethoxysilane, and the like.

  Examples of the diorganodialkoxysilane having two silicon atom-bonded methyl groups and / or ethyl groups include dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldi-n-butoxysilane, dimethyldiacetoxysilane, and diethyldimethoxy. Silane, diethyl diacetoxysilane, etc. are mentioned.

  Among these organoalkoxysilanes (b), the hydrolysis reaction can easily proceed and the by-products after the reaction can be easily removed. Therefore, iso-butyltrimethoxysilane, phenyltrimethoxysilane, and dimethyldimethoxysilane are used. preferable. These organoalkoxysilanes (b) may be used alone or in combination of two or more.

  In addition, in the said manufacturing process (I), although it is also possible to use the hydrolysis-condensation product (b-1) of organoalkoxysilane (b) independently, of composite resin (A'B) by hydrolysis condensation is sufficient. Since it is easy to produce, it is preferable to use an organoalkoxysilane (b) alone or a combination of an organoalkoxysilane (b) and its hydrolysis condensate (b-1), and use an organoalkoxysilane (b) alone. Is particularly preferred. Here, the single use of the organoalkoxysilane (b) is to use only the organoalkoxysilane (b), and includes the case where two or more organoalkoxysilanes (b) are used in combination.

  The hydrolysis condensation reaction in the production step (I) can proceed by various methods, but there is a method in which the reaction is advanced by supplying water and a catalyst during the production step (I). Simple and preferred.

  Examples of the catalyst include inorganic acids such as hydrochloric acid, sulfuric acid, and phosphoric acid; organic acids such as p-toluenesulfonic acid, monoisopropyl phosphate, and acetic acid; inorganic bases such as sodium hydroxide and potassium hydroxide; tetraisopropyl titanate, tetra Titanate esters such as butyl titanate; 1,8-diazabicyclo [5.4.0] undecene-7 (DBU), 1,5-diazabicyclo [4.3.0] nonene-5 (DBN), 1,4 -Compounds containing basic nitrogen atoms such as diazabicyclo [2.2.2] octane (DABCO), tri-n-butylamine, dimethylbenzylamine, monoethanolamine, imidazole, 1-methylimidazole; tetramethylammonium salts , Quaternary anions such as tetrabutylammonium salt and dilauryldimethylammonium salt Quaternary ammonium salts having chloride, bromide, carboxylate, hydroxide, etc. as counter anions; dibutyltin diacetate, dibutyltin dioctoate, dibutyltin dilaurate, dibutyltin diacetylacetonate, tin octylate, Tin carboxylates such as tin stearate can be used alone or in combination of two or more.

  The catalyst is preferably used in an amount of 0.0001 to 10 parts by weight with respect to 100 parts by weight of the organoalkoxysilane (b) and / or its hydrolysis condensate (b-1). More preferably, it is used in the range of ˜3 parts by weight, and particularly preferably in the range of 0.001 to 1 part by weight.

  The water used when the hydrolysis condensation reaction proceeds is based on 1 mol of the hydrolyzable group and hydroxyl group of the organoalkoxysilane (b) and / or the hydrolysis condensate (b-1) thereof. 0.05 mol or more is appropriate, preferably 0.1 mol or more, particularly preferably 0.5 to 3.0 mol.

  The catalyst and water may be supplied collectively or sequentially, or a mixture of the catalyst and water previously supplied may be supplied.

  The reaction temperature of the hydrolysis condensation reaction is suitably in the range of 0 to 150 ° C, and preferably in the range of 20 to 100 ° C. The reaction can be carried out under any conditions of normal pressure, increased pressure, or reduced pressure.

  Alcohol and water, which are by-products that can be generated in the hydrolysis-condensation reaction, may be removed by a method such as distillation when the stability of the resulting aqueous curable coating composition is reduced.

  Next, the alkyltrialkoxysilane condensate (c) having 1 to 3 carbon atoms in the alkyl group used for constituting the polysiloxane segment (C) in the production step (II) will be described in detail.

  Examples of the alkyltrialkoxysilane having 1 to 3 carbon atoms in the alkyl group include, for example, methyltrimethoxysilane, methyltriethoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane, and iso-propyl. Trimethoxysilane and the like can be mentioned. Among them, methyltrimethoxysilane and ethyltrimethoxysilane are preferable because the hydrolysis reaction can easily proceed and by-products after the reaction can be easily removed. These alkyltrialkoxysilanes may be used alone or in combination of two or more.

  The method for obtaining the condensate (c) from the alkyltrialkoxysilane is not particularly limited, and various methods may be mentioned, but a method of proceeding the hydrolysis condensation reaction by supplying water and a catalyst is simple. Is preferable.

  About the water and catalyst used in that case, it can be used on the same conditions as the hydrolysis-condensation reaction in the said manufacturing process (I).

  Moreover, in the said manufacturing process (II), in addition to the condensate (c) of alkyl trialkoxysilane whose alkyl group has 1 to 3 carbon atoms, other silane compounds and hydrolysis condensates thereof may be used in combination. it can.

  Examples of the other silane compounds include tetrafunctional alkoxysilane compounds such as tetramethoxysilane, tetraethoxysilane, and tetra n-propoxysilane; hydrolysis condensates of the tetrafunctional alkoxysilane compounds, and the like. These can be used in combination as long as the effects of the present invention are not impaired.

  When the tetrafunctional alkoxysilane compound or a hydrolysis condensate thereof is used in combination, the tetrafunctional alkoxy is used with respect to 100 mol% of all silicon atoms constituting the polysiloxane segment (B) and the polysiloxane segment (C). It is preferable to use together in the range which the silicon atom which a silane compound and its hydrolysis condensate does not exceed 20 mol%.

  At least one of the structures represented by the general formulas (1-1), (1-2), and (1-3) is introduced into the composite resin (ABC) obtained as described above. As a method, it is preferable to adopt the step (III) described later.

Process (III)
(III) After the composite resin (ABC) obtained in the production step (II) is mixed with an aqueous medium to disperse or dissolve the composite resin (ABC), an aqueous product of the obtained composite resin (ABC) A step of reacting the organoalkoxysilane containing the epoxy group (that is, at least one structure among the structures represented by the general formulas (1-1), (1-2) and (1-3)). And a step of obtaining a composite resin (ABC) contained therein.

  The reaction of the aqueous composite resin (ABC) with an epoxy group-containing organoalkoxysilane is preferably, for example, at 10 to 80 ° C. for 3 to 200 hours. Moreover, you may make both react in a pressurized container as needed.

  The weight ratio of the composite resin (ABC) hydrated product to the epoxy group-containing organoalkoxysilane is such that an epoxy group is contained per 100 parts by weight of the solid content of the composite resin (ABC). The organoalkoxysilane is preferably 0.01 to 100 parts by weight, more preferably 0.05 to 50 parts by weight, and particularly preferably 0.1 to 30 parts by weight.

  Examples of the aqueous medium used in the present invention include water, organic solvents miscible with water, and mixtures thereof. Examples of the organic solvent miscible with water include alcohols such as methanol, ethanol, n- and isopropanol; ketones such as acetone and methyl ethyl ketone; polyalkylene glycols such as ethylene glycol, diethylene glycol and propylene glycol; Alkyl ethers; and lactams such as N-methyl-2-pyrrolidone. In the present invention, only water may be used, a mixture of water and an organic solvent miscible with water may be used, or only an organic solvent miscible with water may be used. From the viewpoint of safety and load on the environment, water alone or a mixture of water and an organic solvent miscible with water is preferable, and only water is particularly preferable.

  The curable aqueous composition of the present invention contains at least one structure among the structures represented by the general formulas (1-1), (1-2), and (1-3) in an aqueous medium. An aqueous product obtained by dispersing or dissolving the composite resin (ABC), preferably containing an aqueous dispersion of the composite resin as an essential component, and optionally containing a curing agent (D) for the composite resin The production method is not limited and can be produced by various methods. Among them, general formulas (1-1), (1-2), and (1-3) can be produced by the production steps (I) to (III). ), A composite resin (ABC) containing at least one type of structure represented by the following formula may be mixed with a curing agent (D) described later.

  Next, the composite resin (ABC) containing at least one kind of the structure represented by the general formulas (1-1), (1-2) and (1-3) used in the present invention is used as necessary. Examples of the curing agent (D) to be used include the following compounds. As a hardening | curing agent (D), the acid group which the composite resin (ABC) containing at least 1 type has the structure represented by the said general formula (1-1), (1-2) and (1-3), and Any compound can be used as long as it has a functional group that reacts with a hydroxyl group bonded to a silicon atom. Examples of the functional group that reacts with a hydroxyl group bonded to an acid group and / or a silicon atom reacts with a carboxyl group such as an isocyanate group or a blocked isocyanate group, but also reacts with a hydroxyl group bonded to a silicon atom; epoxy Group, cyclocarbonate group, amide group, hydroxyl group, oxazoline group, carbodiimide group, hydrazino group and other functional groups that react with carboxyl groups; hydroxyl groups bonded to silicon atoms such as N-hydroxymethylamino groups and N-alkoxymethylamino groups A functional group that reacts with a carboxyl group; a hydroxyl group bonded to a silicon atom; a hydrolyzable group bonded to a silicon atom; a functional group that reacts with a hydroxyl group bonded to a silicon atom such as a carboxyl group;

  Examples of the curing agent (D) include a compound having a silicon atom-bonded hydroxyl group and / or a hydrolyzable group, a compound having an isocyanate group and a silicon atom-bonded hydroxyl group and / or a hydrolyzable group, an epoxy group and a silicon atom bond. Compound having a hydroxyl group and / or hydrolyzable group, polyisocyanate compound, block polyisocyanate compound, polyepoxy compound, polycyclocarbonate compound, amino resin, primary or secondary amide group-containing compound, polycarboxy compound, polyhydroxy Compounds, polyoxazoline compounds, polycarbodiimide compounds, polyhydrazide compounds, etc., among others, compounds having silicon atom-bonded hydroxyl groups and / or hydrolyzable groups, epoxy groups and silicon atom-bonded hydroxyl groups and / or hydrolysis Compound having a functional group, polyisocyanate DOO compounds, blocked polyisocyanate compounds, polyepoxy compounds are preferred. These can be used alone or in combination of two or more.

  The composite resin (ABC) composite resin containing at least one of the structures represented by the general formulas (1-1), (1-2) and (1-3) is a carboxyl group or a neutralized carboxyl. When it has a group, it is preferable that the curing agent (D) is a combination using an epoxy group, a compound having a silicon atom-bonded hydroxyl group and / or a hydrolyzable group, and a polyepoxy compound.

  Examples of the compound having a silicon atom-bonded hydroxyl group and / or a hydrolyzable group include the same silicon atom-bonded hydroxyl groups and / or compounds exemplified as those usable when the composite resin (ABC) is produced. Or the compound which has a hydrolysable group, or these hydrolysis-condensation products etc. are mentioned.

  Examples of the epoxy group and a hydroxyl group having a silicon atom bond and / or a hydrolyzable compound include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3-glycidoxypropyltrimethyl. Ethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, etc., their hydrolysis condensates, vinyl groups having epoxy groups and hydrolyzable silyl groups And copolymers.

  Examples of the polyisocyanate compound include aromatic diisocyanates such as tolylene diisocyanate and diphenylmethane-4,4′-diisocyanate; meta-xylylene diisocyanate, α, α, α ′, α′-tetramethyl-meta-xylyl Aralkyl diisocyanates such as range isocyanate; hexamethylene diisocyanate, lysine diisocyanate, 1,3-bisisocyanate methylcyclohexane, 2-methyl-1,3-diisocyanate cyclohexane, 2-methyl-1,5-diisocyanate cyclohexane Aliphatic or cycloaliphatic diisocyanates such as isophorone diisocyanate:

Various prepolymers having an isocyanate group, obtained by addition reaction of the polyisocyanate compound with polyhydric alcohols; prepolymers having an isocyanurate ring obtained by cyclization and trimerization of the polyisocyanate compound A polyisocyanate having a biuret structure obtained by reacting the polyisocyanate compound with water; 2-isocyanatoethyl (meth) acrylate, 3-isopropenyl-α, α-dimethylbenzyl isocyanate, (meth) Examples thereof include vinyl copolymers containing isocyanate groups obtained from vinyl monomers containing as an essential component a vinyl monomer having an isocyanate group such as acryloyl isocyanate.

  Examples of the block polyisocyanate compound include those obtained by blocking the polyisocyanate compound with various blocking agents. Examples of the blocking agent include alcohols such as methanol, ethanol, and lactic acid esters; phenolic hydroxyl group-containing compounds such as phenol and salicylic acid ester; amides such as ε-caprolactam and 2-pyrrolidone; acetone oxime, methyl ethyl ketoxime, and the like And active methylene compounds such as methyl acetoacetate, ethyl acetoacetate, and acetylacetone.

  Examples of the polyepoxy compound include polyglycidyl ethers of aliphatic or alicyclic polyols such as ethylene glycol, hexanediol, neopentyl glycol, trimethylolpropane, pentaerythritol, sorbitol, and hydrogenated bisphenol A; bisphenol A Polyglycidyl ethers of aromatic diols such as bisphenol S and bisphenol F; polyglycidyl ethers of polyether polyols such as polyethylene glycol, polypropylene glycol and polytetramethylene glycol; tris (2-hydroxyethyl) isocyanurate Polyglycidyl ethers; polyglycidyl esters of aliphatic or aromatic polycarboxylic acids such as adipic acid, butanetetracarboxylic acid, phthalic acid, terephthalic acid; Bisepoxides of hydrocarbon dienes such as crooctadiene and vinylcyclohexene; Alicyclic rings such as bis (3,4-epoxycyclohexylmethyl) adipate and 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexylcarboxylate Formula polyepoxy compounds; vinyl copolymers containing two or more epoxy groups.

  Examples of the polyoxazoline compound include 2,2′-p-phenylene-bis (1,3-oxazoline), 2,2′-tetramethylene-bis (1,3-oxazoline), 2,2′-octa Low molecular weight poly (1,3-oxazoline) compound such as methylene-bis (2-oxazoline); single weight of 1,3-oxazoline group-containing vinyl monomer such as 2-isopropenyl-1,3-oxazoline Examples thereof include vinyl polymers containing 1,3-oxazoline groups obtained by copolymerization or copolymerization with a vinyl monomer copolymerizable therewith.

  Examples of the polyhydrazide compound include dihydrazide compounds of organic acids such as oxalic acid dihydrazide, malonic acid dihydrazide, and succinic acid dihydrazide.

  Examples of the amino resin include alkylol groups obtained by reacting amino group-containing compounds such as melamine, benzoguanamine, acetoguanamine, urea, and glycouril with aldehyde compounds (or aldehyde supply substances) such as formaldehyde and acetaldehyde. Examples of the amino resin having an alkylol group include alkoxyalkyl group-containing amino resins obtained by reacting the amino resin having an alkylol group with a lower alcohol such as methanol, ethanol, n-butanol, and iso-butanol.

  The amount of the curing agent (D) used is, for example, a compound in which the curing agent (D) has a silicon atom-bonded hydroxyl group and / or hydrolyzable group, a block polyisocyanate compound, an amino resin, or a polycarboxy compound. In this case, the solid content of the curing agent (D) is preferably in the range of 0.1 to 200 parts by weight, and 0.5 to 150 parts by weight with respect to 100 parts by weight of the composite resin (ABC). More preferably, it is in the range of 1 part by weight, and particularly preferably in the range of 1 to 100 parts by weight.

  Further, for example, the curing agent (D) is a compound having an epoxy group and a silicon atom-bonded hydroxyl group and / or a hydrolyzable group, a polyepoxy compound, a polycyclocarbonate compound, a primary or secondary amide group-containing compound, poly When it is a compound having a group that reacts with a carboxyl group such as a hydroxy compound, a polyoxazoline compound, a polycarbodiimide compound, a polyhydrazide compound, and the composite resin (ABC) is a composite resin containing a carboxyl group, Groups (epoxy group, cyclocarbonate group, amide group, hydroxyl group, oxazoline group carbodiimide group, hydrazino group) that react with the carboxyl group in the curing agent (D) with respect to 1 equivalent of the carboxyl group in the composite resin (ABC). Etc.) is preferably in the range of 0.2 to 5.0 equivalents, 0 5 to 3.0, more preferably in the range of equivalents, and particularly preferably in the range of 0.7 to 2.0 equivalents.

  Moreover, as a specific example of the said hardening | curing agent (D), the composite resin (ABC) which contains at least 1 type of structure represented by the said General formula (1-1), (1-2), and (1-3). Are not easily separated when mixed with an aqueous dispersion in which the aqueous solution is dissolved or dispersed, for example, has a level of hydrophilicity that can be dispersed or dissolved in the aqueous medium. Those that are uniformly dispersed or dissolved, cannot be dispersed or dissolved alone in the aqueous medium, but when mixed with the aqueous dispersion, intrusion, fusion, adsorption, etc. into the composite resin (ABC) particles occur, and as particles What is integrated is mentioned. Examples of those that are uniformly dispersed or dissolved in the aqueous dispersion include, for example, non-volatile content of 80% by weight, “Elastolon BN-77” manufactured by Daiichi Kogyo Seiyaku Co., Ltd. In addition, examples of those integrated with composite resin (ABC) particles upon mixing with the aqueous dispersion include, for example, Examples 1-4, 8, and 9 described later. 3-glycidoxypropyltrimethoxysilane (3GPTMS) used, “MKC silicate MS-51” (polymethoxysiloxane having a condensation degree of 2 to 9) manufactured by Mitsubishi Chemical Corporation, “Denacol manufactured by Nagase ChemteX Corporation” EX-614B "(epoxy compound having an epoxy equivalent of 173 g / eq) and the like.

  In addition, an isocyanate group-containing compound such as “Bernock DNW-5000” (an aqueous dispersion of a polyisocyanate compound having an isocyanate group content of 13.5% by weight) manufactured by DIC Corporation, as long as the effects of the present invention are not impaired. Oxazoline group-containing compound names such as “Epocross WS-500” manufactured by Nippon Shokubai Co., Ltd. (an aqueous solution of a 1,3-oxazoline group-containing water-soluble resin having an oxazoline group equivalent of 220 g / eq) May be used as the curing agent (D).

  The curable aqueous composition of the present invention may contain a thermosetting resin as necessary. Examples of such thermosetting resins include vinyl resins, polyester resins, polyurethane resins, epoxy resins, epoxy ester resins, acrylic resins, phenol resins, petroleum resins, ketone resins, silicon resins, or modified resins thereof.

  Although various inorganic particles, such as a clay mineral, a metal, a metal oxide, or glass, can be used for the curable aqueous composition of this invention as needed, it is preferable not to use normally. Gold, silver, copper, platinum, titanium, zinc, nickel, aluminum, iron, silicon, germanium, antimony, etc. can be used as the kind of metal, and those metal oxides can also be used. It is.

  In the curable aqueous composition of the present invention, an inorganic pigment, an organic pigment, an extender pigment, a dye, a wax, a surfactant, a stabilizer, a flow regulator, an antifoaming agent, a leveling agent, a rheology control agent, if necessary Known and commonly used additives such as ultraviolet absorbers, antioxidants, and plasticizers can be used.

  Such a curable aqueous composition of the present invention can be used as a resin for coating architectural outer walls, has a high low-temperature curing rate, a long pot life, and good workability.

  Although there is no restriction | limiting in particular in the film thickness of the coating film formed using the curable aqueous composition of this invention as resin for building exterior wall coating, It is preferable that it is 0.1-100 micrometers, and it is 1-50 micrometers. Is more preferable, and it is most preferable that it is 3-30 micrometers. If it is the film thickness in the said range, the crack which may arise in a cured coating film can be suppressed and the cured coating film which has the outstanding weather resistance can be formed.

  As a method of applying the curable aqueous composition to the building outer wall, for example, various coating methods such as a roller coating method, a spray coating method, and a brush coating method can be applied.

  After applying the curable aqueous composition of the present invention to the building outer wall by the coating method, it is allowed to stand at room temperature for about 1 to 10 days, whereby a coating film excellent in weather resistance, low contamination and the like can be obtained.

  Next, the present invention will be specifically described with reference to examples and comparative examples. In the examples, all parts and% are based on weight.

Example 1
Into a reaction vessel equipped with a stirrer, a thermometer, a dropping funnel, a condenser tube and a nitrogen gas inlet, 1421 parts of methyltrimethoxysilane (MTMS) was charged and heated to 60 ° C. Subsequently, a mixture of 0.17 part of “A-3” (iso-propyl acid phosphate manufactured by Sakai Chemical Co., Ltd.) and 207 parts of deionized water was added dropwise over 5 minutes. After completion of the dropwise addition, the temperature in the reaction vessel was raised to 80 ° C. and stirred for 4 hours to conduct a hydrolysis condensation reaction. Subsequently, the obtained condensate is reduced under a reduced pressure of 300 to 10 mmHg (note that the reduced pressure condition at the start of the distillation of methanol is 300 mmHg and finally reduced to 10 mmHg. The same applies hereinafter). By removing the generated methanol and water within a temperature range of 40 to 60 ° C., a condensate of methyltrimethoxysilane having a number average molecular weight of 1,000 and an active ingredient of 70.0% in the reaction solution ( c-1) 1,000 parts were obtained.
Next, 111 parts of isopropanol (IPA) and 54 parts of phenyltrimethoxysilane (PTMS) were charged into the same reaction vessel as described above, and the temperature was raised to 80 ° C. Next, 112 parts of methyl methacrylate (MMA), 92 parts of butyl methacrylate (BMA), 52 parts of butyl acrylate (BA), 16 parts of acrylic acid (AA), 3-methacryloxypropyltrimethoxysilane (MPTS) at the same temperature. 4 parts, a mixture containing 50.9 parts of IPA and 14 parts of tert-butylperoxy-2-ethylhexanoate (TBPEH) was dropped into the reaction vessel over 4 hours. By reacting for 2 hours, a polymer (a′-1) having a number average molecular weight of 10,000 having both a carboxyl group and a hydrolyzable group bonded to a silicon atom is obtained. Next, 32.5 parts of dimethyldimethoxysilane (DMDMS) was charged therein at the same temperature, and then a mixture of 0.88 part of “A-3” and 24 parts of deionized water was added dropwise over 5 minutes. And a hydrolytic condensation reaction by stirring for 3 hours, and a composite resin (A′B-1) comprising a polymer segment having both a carboxyl group and a hydrolyzable group bonded to a silicon atom, and a polysiloxane segment derived from PTMS and DMDMS. ) Next, the obtained reaction liquid was cooled to 60 ° C., and 15 parts of butyl carbitol, 9.9 parts of 2-dimethylaminoethanol, and 93 parts of a condensate of methyltrimethoxysilane (c-1) were added at the same temperature. In the composite resin (A'BC-1) in which the polysiloxane segment (C-1) derived from the condensate (c-1) of the composite resin (A'B-1) and methyltrimethoxysilane is bonded The composite resin (ABC-1) was obtained by neutralizing the carboxyl group, and then dispersed in an aqueous medium by adding 570 parts of deionized water. Next, the resulting reaction solution was distilled under reduced pressure of 300 to 10 mmHg for 2 hours under the conditions of 40 to 60 ° C. to remove the generated methanol and water, and a composite resin (non-volatile content: 40.0%) 1,000 parts of an aqueous dispersion of ABC-1) were obtained. Next, a mixed solution in which 1.0 part of 3-glycidoxypropyltrimethoxysilane (3GPTMS) was mixed with 100 parts of the aqueous dispersion of the composite resin (ABC-1) was placed in a sealed container and placed in a thermostatic bath at 50 ° C. For 24 hours to obtain a curable aqueous composition of the present invention.

  Next, a mixed solution (p-1) obtained by mixing 4.0 parts of 3GPTMS with the obtained low-temperature curable aqueous composition was applied on a glass plate so that the dry film thickness was 10 μm, and dried at 5 ° C. for 6 hours. And a coating film (P-1) was obtained. Subsequently, the water resistance of the obtained coating film (P-1) was evaluated. In addition, the water resistance is left for 60 minutes with a water drop on the coated surface. Then remove the water droplets and observe the appearance. At that time, it was determined that the smaller the change in appearance, the faster the curing. As an evaluation result of water resistance of the coating film (P-1), there was no coating film peeling. In addition, it was confirmed that the mixed solution (p-1) could be used after 6 hours and the pot life was long.

Example 2
A mixed solution prepared by mixing 1.2 parts of 3-glycidoxypropyltriethoxysilane (3GPTES) with 100 parts of the aqueous dispersion of the composite resin (ABC-1) produced in Example 1 was put in a sealed container, and 50 ° C. The curable aqueous composition of the present invention was obtained by leaving it in a constant temperature bath for 24 hours.

  Next, a mixed solution (p-2) prepared by mixing 4.8 parts of 3GPTES with the obtained curable aqueous composition was applied on a glass plate so that the dry film thickness was 10 μm, and dried at 5 ° C. for 6 hours. A coating film (P-2) was obtained. Subsequently, the water resistance of the obtained coating film (P-2) was evaluated in the same manner as in Example 1. As a result of evaluating the water resistance of the coating film (P-2), there was no peeling of the coating film. Moreover, after preparing the said liquid mixture (p-2), it can be used 6 hours later, and it confirmed that the pot life was long.

Example 3
A mixed solution prepared by mixing 2.5 parts of 3GPTMS and 100 parts of deionized water with 100 parts of the aqueous dispersion of the composite resin (ABC-1) produced in Example 1 was placed in a sealed container and placed in a thermostatic bath at 50 ° C. The curable aqueous composition of the present invention was obtained by allowing to stand for 24 hours.

  Next, a mixed solution (p-3) obtained by mixing 2.5 parts of 3GPTMS with the obtained curable aqueous composition was applied on a glass plate so that the dry film thickness was 10 μm, and dried at 5 ° C. for 6 hours. A coating film (P-3) was obtained. Subsequently, the water resistance of the obtained coating film (P-3) was evaluated in the same manner as in Example 1. As a result of evaluating the water resistance of the coating film (P-3), there was no coating film peeling. Moreover, the said liquid mixture (p-3) was prepared, and it could be used even 6 hours afterward, and this formulation had a long pot life.

Example 4
Aqueous dispersion of composite resin (ABC-2) having a nonvolatile content of 40.0% in the same manner as in Example 1 except that 87 parts of MMA, 85 parts of BMA, 48 parts of AA, and 29.7 parts of 2-dimethylaminoethanol were used. 1,050 parts of body were obtained. Next, a mixed solution prepared by mixing 12.6 parts of 3GPTES and 300 parts of deionized water with 100 parts of the aqueous dispersion of the composite resin (ABC-2) is placed in a sealed container and left in a thermostatic bath at 50 ° C. for 24 hours. Thus, a curable aqueous composition of the present invention was obtained.

  Next, a mixed solution (p-4) obtained by mixing 5.4 parts of 3GPTS with the obtained curable aqueous composition was applied on a glass plate so that the dry film thickness was 5 μm, and dried at 5 ° C. for 6 hours. A coating film (P-4) was obtained. Subsequently, the water resistance of the obtained coating film (P-4) was evaluated in the same manner as in Example 1. As a result of evaluating the water resistance of the coating film (P-4), there was no peeling of the coating film. Further, the mixture (p-4) was prepared and could be used after 6 hours, and the blend had a long pot life.

Comparative Example 1
A mixed liquid (r-1) in which 5 parts of 3GPTMS was mixed with 100 parts of the aqueous dispersion of the composite resin (ABC-1) produced in Example 1 was obtained. Subsequently, the obtained mixed liquid (r-1) was applied onto a glass plate so that the dry film thickness was 20 μm, and dried at 5 ° C. for 6 hours to obtain a coating film (R-1). Subsequently, the water resistance of the obtained coating film (R-1) was evaluated in the same manner as in Example 1. The coating film (R-1) was insufficiently cured, peeled off from the coating film, and lacked water resistance. Moreover, the said liquid mixture (r-1) can be used even 6 hours after preparing, and this formulation had a long pot life.

Comparative Example 2
A mixed liquid (r-2) in which 6 parts of 3-glycidoxypropyltriethoxysilane (3GPTES) was mixed with 100 parts of the aqueous dispersion of composite resin (ABC-1) produced in Example 1 was obtained. Next, the obtained (r-2) was applied onto a glass plate so that the dry film thickness was 20 μm, and dried at 5 ° C. for 6 hours to obtain a coating film (R-2). Subsequently, the water resistance of the obtained coating film (R-2) was evaluated in the same manner as in Example 1. The coating film (R-2) was insufficiently cured, peeled off from the coating film, and lacked water resistance. Moreover, the said liquid mixture (r-2) can be used even 6 hours after preparing, and this formulation had a long pot life.

Comparative Example 3
A mixed liquid (r-3) in which 18 parts of 3GPTES was mixed with 100 parts of the aqueous dispersion of composite resin (ABC-2) produced in Example 4 was obtained. Next, the obtained (r-3) was applied onto a glass plate so that the dry film thickness was 5 μm, and dried at 5 ° C. for 6 hours to obtain a coating film (R-3). Subsequently, the water resistance of the obtained coating film (R-3) was evaluated in the same manner as in Example 1. The coating film (R-3) was insufficiently cured, peeled off from the coating film, and lacked water resistance. Moreover, the said liquid mixture (r-3) can be used even 6 hours after preparing, and this formulation had a long pot life.

Comparative Example 4
“Bernock DNW-5000” (made by DIC Corporation) (polyisocyanate compound having an isocyanate group content of 13.5% by weight) was added to 100 parts of the aqueous dispersion of composite resin (ABC-1) produced in Example 1 above. A mixed liquid (r-5) was obtained by mixing 10 parts of a dispersion (non-volatile content: 80% by weight). Next, the obtained (r-5) was applied on a glass plate so that the dry film thickness was 20 μm, and dried at 5 ° C. for 6 hours to obtain a coating film (R-5). Subsequently, the water resistance of the obtained coating film (R-1) was evaluated in the same manner as in Example 1. As an evaluation result of the coating film (R-1), there was no peeling of the coating film. However, since the mixed solution (r-5) was prepared and gelled after 3 hours and became unusable, the pot life was short.

Claims (11)

The polysiloxane segment (B) of the composite resin (AB) in which the polymer segment (A) having a neutralized acid group and the polysiloxane segment (B) are chemically bonded, and the alkyl group has 1 carbon atom. A composite resin (ABC) in which the polysiloxane segment (C) derived from the condensate of alkyl trialkoxysilane (c) to 3 is bonded via a silicon-oxygen bond is dissolved or dispersed in an aqueous medium. A curable aqueous composition containing an aqueous product of a composite resin (ABC), wherein the composite resin (ABC) is represented by the following general formulas (1-1), (1-2), and (1-3). Among the structures, the polysiloxane segment (B) has a structure represented by the following general formula (S-4) and / or (S-5). Curing characterized by Aqueous composition.

(In the formula, m and n each independently represent 1 to 4 repeating units, k represents 4 to 12 repeating units, and X ¹ and X ² each independently represent a hydroxyl group, a methoxy group, or an ethoxy group. X ³ represents a hydroxyl group, a methyl group, a methoxy group, an ethoxy group, a propoxy group, or a butoxy group, R ¹ represents an organic group having 4 to 12 carbon atoms bonded to a silicon atom, R ² and R ³ each independently represent a methyl group bonded to a silicon atom or an ethyl group bonded to a silicon atom.
2. The curable aqueous composition according to claim 1, wherein the composite resin (ABC) is a composite resin containing 25 to 85 wt% of the polysiloxane segment (B) and the polysiloxane segment (C) in total. The curable aqueous composition according to claim 2, wherein the composite resin (ABC) is a composite resin containing 15 to 60% by weight of the polysiloxane segment (C). In the composite resin (ABC), the polymer segment (A) and the polysiloxane segment (B) are represented by the following structural formula (S-1).

[However, the carbon atom in the structural formula (S-1) constitutes a part of the polymer segment (A), and the silicon atom and the oxygen atom constitute a part of the polysiloxane segment (B). ]
The curable aqueous composition according to claim 1, 2 or 3, which is a composite resin bonded through a bond represented by: The curable aqueous composition according to claim 4, wherein the polymer segment (A) is a segment derived from a vinyl polymer. The curable aqueous composition according to claim 1, 2 or 3, wherein the alkyltrialkoxysilane condensate (c) is a condensate obtained by hydrolytic condensation of methyltrimethoxysilane and / or methyltriethoxysilane. object. Further, a compound having a hydroxyl group bonded to a silicon atom and / or a hydrolyzable group bonded to a silicon atom, a compound having an isocyanate group and a hydrolyzable group bonded to a silicon atom in one molecule, an epoxy group in one molecule And a compound having a hydrolyzable group bonded to a silicon atom, a polyisocyanate compound, a blocked isocyanate compound, a polyepoxy compound, a polycyclocarbonate compound, an amino resin, a primary or secondary amide group-containing compound, a polycarboxy compound, and a polyhydroxy The curable aqueous composition according to claim 1, comprising a curing agent (D) which is at least one compound selected from the group consisting of compounds. The following steps (I) to (III),
(I) a polymer (a ′) having both an acid group and a hydroxyl group bonded to a silicon atom and / or a hydrolyzable group bonded to a silicon atom, an organoalkoxysilane (b) and / or a hydrolysis condensate thereof ( b-1) is hydrolyzed and condensed, and the polymer segment (A ′) derived from the polymer (a ′) and the polysiloxane segment (B) derived from the organoalkoxysilane (b) are chemically bonded. Obtaining a resin (A′B);
(II) Next, the resulting composite resin (A′B) and the alkyltrialkoxysilane condensate (c) having 1 to 3 carbon atoms in the alkyl group are hydrolytically condensed to give the composite resin (A′B). The polysiloxane segment (B) and the polysiloxane segment (C) derived from the condensate (c) of alkyltrialkoxysilane having 1 to 3 carbon atoms in the alkyl group are bonded via a silicon-oxygen bond. A step of obtaining a composite resin (ABC) by neutralizing acid groups in the composite resin (A'BC) with a basic compound after the composite resin (A'BC) is obtained, or the obtained composite resin (A'BC) After the acid group in ′ B) is neutralized with a basic compound to form a composite resin (AB), the condensation product (c) of alkyltrialkoxysilane having 1 to 3 carbon atoms in the alkyl group is hydrolyzed and condensed. Polysiloxane segment of composite resin (AB) Composite resin (B) and a polysiloxane segment (C) derived from a condensate (c) of alkyltrialkoxysilane having 1 to 3 carbon atoms of an alkyl group bonded via a silicon-oxygen bond ( ABC)
(III) Next, the obtained composite resin (ABC) is mixed with an aqueous medium to disperse or dissolve the composite resin (ABC) to obtain an aqueous product of the composite resin (ABC), and then the composite resin (ABC). The curable aqueous composition according to claim 1, 2 or 3, which is an aqueous composition obtained by a production method comprising the step of reacting the above aqueous product with an organoalkoxysilane containing an epoxy group. The organoalkoxysilane (b) is a monoorganotrialkoxysilane having a C 4-12 organic group bonded to a silicon atom and / or a methyl group bonded to a silicon atom and / or an ethyl group bonded to a silicon atom. The curable aqueous composition according to claim 8, which is a diorganodialkoxysilane having two. The curable aqueous composition according to claim 9, wherein the organic group having 4 to 12 carbon atoms is an alkyl group, a cycloalkyl group, an aryl group, or an aralkyl group. The curable aqueous composition according to claim 8, wherein the polymer (a ') is a vinyl polymer.