JP2014196418A - Aqueous resin composition and article obtained by applying the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an aqueous resin composition capable of forming a coating film which is excellent in hot water resistance, corrosion resistance, and chemical resistance and is capable of preventing deterioration of various substrates.SOLUTION: The present invention relates to the aqueous resin composition containing: a urethane resin (A) which has a hydrolyzable silyl group or a silanol group, and a polymerizable unsaturated group; and an aqueous medium (B). The urethane resin (A) is obtained by reacting a polyol (a1) containing a diol (a1-1) having a polymerizable unsaturated group, a polyisocyanate (a2), and an alkoxysilane (a3) having an amino group or an isocyanate group.

Description

  The present invention relates to an aqueous resin composition that can be used for surface coating of various substrates such as plastic substrates and metal substrates.

  The coating agent is generally required to be able to form a coating film having a level of durability that can prevent deterioration of the surface of the substrate. In particular, in recent years, in addition to (warm) water resistance, a coating agent that can form a coating film with chemical resistance and corrosion resistance at a level that can prevent deterioration of the substrate due to adhesion of chemicals such as cleaning agents, acid rain, etc. However, there is a demand from industry.

  The coating agent having the above-mentioned characteristics is often required especially for the surface protection of a plastic base material that easily deteriorates due to adhesion of chemicals or the like and a metal base material that easily generates rust.

  Examples of the coating agent that can be used for surface protection of the plastic substrate include polymer particles, a polyfunctional epoxy compound, and an aqueous medium, and the polymer particles are composed of at least two layers, of which A curable polymer aqueous dispersion in which the A phase is composed of a carboxyl group-containing polymer and the B phase is an ethylenic polymer having a basic nitrogen atom-containing group is known (for example, see Patent Document 1). .

  However, the coating film formed using the aqueous dispersion of the curable polymer can prevent deterioration of the plastic substrate and the metal substrate over a long period of time in terms of hot water resistance, corrosion resistance, and chemical resistance. It wasn't a step further. In particular, there were cases where it was not practically sufficient to prevent the occurrence of rust on the metal substrate.

JP 9-235332 A

  The problem to be solved by the present invention is to provide an aqueous resin composition that is excellent in warm water resistance, corrosion resistance, and chemical resistance and that can form a coating film that can prevent deterioration of various substrates.

  The present inventors have found that the above problem can be solved by using a specific urethane resin having a polymerizable unsaturated group in the side chain.

  That is, the present invention contains a urethane resin (A) having a hydrolyzable silyl group or silanol group and a polymerizable unsaturated group, and an aqueous medium (B), and the urethane resin (A) is polymerized. It is obtained by reacting a polyol (a1) containing a diol (a1-1) having a polymerizable unsaturated group, a polyisocyanate (a2), and an alkoxysilane (a3) having an amino group or an isocyanate group. The present invention relates to an aqueous resin composition.

  Since the aqueous resin composition of the present invention can form a coating film excellent in warm water resistance, corrosion resistance and chemical resistance, it can be used as a surface protective coating agent for metal substrates such as plastic substrates and steel plates. Can be used. Specifically, the aqueous resin composition of the present invention has a plastic group such as acrylonitrile-butadiene-styrene resin (ABS resin), polycarbonate resin (PC resin), ABS / PC resin, polystyrene resin (PS resin), and PMMA resin. Since it can be suitably used for surface protection of materials, it can be used for painting mobile phones, home appliances, OA equipment, automobile interior materials and the like.

  In addition, the aqueous resin composition of the present invention generates rust on metal substrates such as galvanized steel sheets, aluminum-zinc alloy steel sheets, aluminum sheets, aluminum alloy sheets, electromagnetic steel sheets, copper sheets, stainless steel sheets, etc. Because it can form a coating with excellent corrosion resistance that can be prevented, it must be used for coating exterior parts, roofing and other building components, guardrails, soundproof walls, drainage and other civil engineering components, household appliances, industrial machinery, automotive parts, etc. Is possible.

  The aqueous resin composition of the present invention contains a urethane resin (A) having a hydrolyzable silyl group or silanol group and a polymerizable unsaturated group, and an aqueous medium (B), and the urethane resin (A). Is obtained by reacting a polyol (a1) containing a diol (a1-1) having a polymerizable unsaturated group, a polyisocyanate (a2), and an alkoxysilane (a3) having an amino group or an isocyanate group. It is characterized by that.

  The urethane resin (A) used in the present invention has either or both of a hydrolyzable silyl group and a silanol group.

  The hydrolyzable silyl group can be hydrolyzed by contact with water or the like to form a silanol group in which a hydroxyl group is bonded to a silicon atom.

  The hydrolyzable silyl group and silanol group can react with a self-condensation reaction or other functional groups when forming a coating film. Thereby, it becomes possible to form a coating film excellent in hot water resistance, corrosion resistance and chemical resistance.

  The hydrolyzable silyl group and silanol group have a structure derived from an alkoxysilane (a3) having an amino group or an isocyanate group that is used when the urethane resin (A) is produced. The hydrolyzable silyl group and silanol group derived from) may be used.

  It is even better that the urethane resin (A) has a structure derived from the alkoxysilane (a3) in the range of 0.1% by mass to 10% by mass with respect to the entire urethane resin (A). It is preferable for forming a coating film having high water resistance, corrosion resistance and chemical resistance.

  The urethane resin (A) contains an atomic group composed of oxygen atoms and silicon atoms derived from the alkoxysilane (a3) and a polyalkoxysilane (X) described later with respect to the total amount of the urethane resin (A). In order to form a coating film having even more excellent hot water resistance, corrosion resistance, and chemical resistance, it is preferable that the content be in the range of 0.1% by mass to 40% by mass.

  In addition, as the urethane resin (A), a resin having a polymerizable unsaturated group is used for forming a coating film having excellent warm water resistance, corrosion resistance, and chemical resistance. The said polymerizable unsaturated group exists in the side chain with respect to the principal chain of the urethane resin (A) mainly having a urethane bond. Examples of the polymerizable unsaturated group include polymerizable unsaturated double bonds capable of radical polymerization.

  As said urethane resin (A), it is preferable to use what has the said polymerizable unsaturated group in the range of 0.2 mmol / g-3 mmol / g with respect to 1 g of said urethane resin (A). It is more preferable to use those having a content in the range of / g to 2 mmol / g in order to form a coating film that is further excellent in hot water resistance, corrosion resistance, and chemical resistance.

  Moreover, as said urethane resin (A), it is preferable to use what has a hydrophilic group, when melt | dissolving or disperse | distributing stably in an aqueous medium (B).

  Examples of the hydrophilic group include an anionic group, a cationic group, and a nonionic group.

  As the anionic group, for example, a carboxyl group, a sulfonic acid group, a carboxylate group, a sulfonate group, or the like in which part or all of them are neutralized with a basic compound described later can be used. Of these, the use of a carboxyl group or a carboxylate group is preferable for imparting good water dispersibility to the urethane resin (A).

  Examples of the cationic group include a tertiary amino group. The tertiary amino group may be partially or entirely neutralized with an organic acid such as acetic acid or propionic acid; or an inorganic acid such as phosphoric acid.

  Examples of the nonionic group include a polyoxyethylene group and a polyoxyethylene-polyoxypropylene group.

  The hydrophilic group such as the anionic group is present in the range of 50 mmol / kg to 1,000 mmol / kg with respect to 1 kg of the urethane resin (A), so that the urethane resin (A) in the aqueous medium (B) is present. It is preferable for imparting good water dispersion stability.

  The urethane resin (A) has a weight average molecular weight in the range of 10,000 to 500,000 in order to form a coating film excellent in warm water resistance, corrosion resistance and chemical resistance. It is preferable to use those having a weight average molecular weight in the range of 20,000 to 200,000, and it is more preferable to use a weight average molecular weight in the range of 40,000 to 100,000.

  Moreover, as said urethane resin (A), it is preferable to use what has a urea bond in addition to forming the coating film which was further excellent in warm water resistance, corrosion resistance, and chemical resistance.

  As the urethane resin (A), it is possible to use a resin having a urea bond equivalent in the range of 500 to 50,000 to form a coating film having further excellent warm water resistance, corrosion resistance, and chemical resistance. In addition, it is preferable.

  The urethane resin (A) includes a polyol (a1) containing a diol (a1-1) having a polymerizable unsaturated group, a polyisocyanate (a2), and an alkoxysilane (a3) having an amino group or an isocyanate group. If necessary, it can be produced by reacting with a chain extender or the like.

  Specifically, the urethane resin (A) is a step of producing a urethane resin (A ′) having an isocyanate group or a hydroxyl group at a terminal by reacting the polyol (a1) with the polyisocyanate (a2) [ 1] and the step [2] of reacting the urethane resin (A ′) with the alkoxysilane (a3).

  When the alkoxysilane having two or more functional groups selected from the group consisting of an amino group and an isocyanate group is used as the alkoxysilane (a3), the urethane resin (A) contains the polyol (a1), the polyisocyanate ( It can also be produced by mixing and reacting a2) with the alkoxysilane (a3).

  The polyol (a1) that can be used for the production of the urethane resin (A) is a diol (a1) having a polymerizable unsaturated group when a polymerizable unsaturated group is introduced into the side chain of the urethane resin (A). -1) is used.

  Examples of the diol (a1-1) include (meth) acrylic monomers such as pentaerythritol di (meth) acrylate and dipentaerythritol tetra (meth) acrylate; compounds having an epoxy group and (meth) having a carboxyl group Diols obtained by reacting with acrylic monomers can be used.

  Examples of the compound having an epoxy group include diglycidyl ether of bisphenol A, diglycidyl ether of bisphenol F, 1,6-hexanediol diglycidyl ether, 1,4-butanediol diglycidyl ether, neopentyl glycol diglycidyl ether. It is preferable to use a compound having two or more epoxy groups such as.

  As the (meth) acrylic monomer having a carboxyl group, for example, (meth) acrylic acid, itaconic acid, maleic acid, maleic anhydride, fumaric acid and the like can be used.

  The diol (a1-1) is preferably used in the range of 5% by mass to 70% by mass with respect to the total amount of the polyol (a1) in order to form a flexible coating film.

  Moreover, when using the urethane resin which has a hydrophilic group as said urethane resin (A), it is preferable to use the polyol which has a hydrophilic group as said polyol (a1).

  As the polyol having a hydrophilic group, for example, a polyol having an anionic group, a polyol having a cationic group, and a polyol having a nonionic group can be used. Among these, it is preferable to use a polyol having an anionic group.

  As the polyol having an anionic group, for example, a polyol having a carboxyl group or a polyol having a sulfonic acid group can be used.

  Examples of the polyol having a carboxyl group include 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, 2,2-dimethylolvaleric acid, and the like. Preference is given to using methylolpropionic acid. Moreover, the polyester polyol which has a carboxyl group obtained by making the polyol which has the said carboxyl group, and various polycarboxylic acids react can also be used.

  Examples of the polyol having a sulfonic acid group include dicarboxylic acids such as 5-sulfoisophthalic acid, sulfoterephthalic acid, 4-sulfophthalic acid, and 5 [4-sulfophenoxy] isophthalic acid, and salts thereof, and ethylene glycol and propylene glycol. , 1,4-butanediol, 1,6-hexanediol, diethylene glycol, polyester polyol obtained by reacting with a low molecular polyol such as neopentyl glycol, the polyester polyol, and γ-butyrolactone, δ-valerolactone, A polyester polyol obtained by reacting a cyclic ester compound such as ε-caprolactone can be used.

  The anionic groups are preferably partially or wholly neutralized with a basic compound or the like in order to exhibit good water dispersibility.

  Examples of basic compounds that can be used for neutralizing the anionic group include organic amines having a boiling point of 200 ° C. or higher, such as ammonia, triethylamine, morpholine, monoethanolamine, diethylethanolamine; sodium hydroxide, hydroxide A metal hydroxide containing potassium, lithium hydroxide or the like can be used. From the viewpoint of improving the water dispersion stability of the obtained aqueous resin composition, the basic compound is [basic compound / (total amount of acid groups such as carboxyl groups)] = 0.5 to 3 (molar ratio). It is preferable to use in the range which becomes, and it is more preferable to use in the range used as 0.7-1.5 (molar ratio).

  Further, as the polyol having a cationic group, for example, a polyol having a tertiary amino group can be used. Specifically, N-methyl-diethanolamine, a compound having two epoxies in one molecule and a secondary compound can be used. A polyol or the like obtained by reacting with an amine can be used.

  It is preferable that a part or all of the cationic group is neutralized with an acidic compound such as formic acid, acetic acid, propionic acid, succinic acid, glutaric acid, tartaric acid, adipic acid, and phosphoric acid.

  Further, the tertiary amino group as the cationic group is preferably partly or entirely quaternized. As the quaternizing agent, for example, dimethyl sulfate, diethyl sulfate, methyl chloride, ethyl chloride and the like can be used, and dimethyl sulfate is preferably used.

  Moreover, as the polyol having the nonionic group, polyalkylene glycol having a structural unit derived from ethylene oxide can be used.

  The polyol having a hydrophilic group is preferably used in the range of 0.1% by mass to 30% by mass with respect to the total amount of the polyol (a1).

  Moreover, as said polyol (a1), in addition to the above-mentioned diol (a1-1) and the polyol which has a hydrophilic group, the other polyol which can be used as needed can be used in combination.

  As said other polyol, polyester polyol, polyether polyol, polycarbonate polyol etc. can be used, for example, It is preferable to use polyester polyol.

  Examples of the polyester polyol include a polyester polyol obtained by reacting a low molecular weight polyol and a polycarboxylic acid; a polyester polyol obtained by a ring-opening polymerization reaction of a cyclic ester compound such as ε-caprolactone; The polyester polyol obtained by doing this can be used.

  Examples of the low molecular weight polyol include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, diethylene glycol, neopentyl glycol, and 1,3-butanediol having a molecular weight of about 50 to 300. Aliphatic polyols such as cyclohexane dimethanol and the like; polyols having an aromatic structure such as bisphenol compounds such as bisphenol A and bisphenol F can be used. Of these, 1,6-hexanediol and neopentyl glycol are preferably used.

  Examples of the polycarboxylic acid that can be used in the production of the polyester polyol include aliphatic polycarboxylic acids such as succinic acid, adipic acid, sebacic acid, and dodecanedicarboxylic acid; terephthalic acid, isophthalic acid, phthalic acid, naphthalenedicarboxylic acid, and the like. Aromatic polycarboxylic acids of the above; anhydrides or esterified products thereof can be used.

  The other polyol is preferably used in a range of 15% by mass to 80% by mass with respect to the total amount of the polyol (a1), and is preferably used in a range of 20% by mass to 60% by mass. It is preferable for further improvement.

  Examples of the polyisocyanate (a2) used in the production of the urethane resin (A) include polyisocyanates having an aliphatic cyclic structure such as cyclohexane diisocyanate, dicyclohexylmethane diisocyanate, and isophorone diisocyanate; 4,4′-diphenylmethane diisocyanate. , 2,4'-diphenylmethane diisocyanate, carbodiimide modified diphenylmethane diisocyanate, crude diphenylmethane diisocyanate, phenylene diisocyanate, tolylene diisocyanate, naphthalene diisocyanate, etc .; hexamethylene diisocyanate, lysine diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate Aliphatic polyisocyanates such as It can be used over door. Among these, it is preferable to use dicyclohexylmethane diisocyanate or isophorone diisocyanate as the polyisocyanate (a2) in order to form a coating film having excellent warm water resistance, corrosion resistance, and chemical resistance.

  Moreover, as alkoxysilane (a3) used for manufacture of the said urethane resin (A), what has any one or both of an amino group or an isocyanate group is used. Part or all of the hydrolyzable silyl group such as an alkoxysilyl group contained in the alkoxysilane (a3) may be hydrolyzed to form a silanol group.

  Examples of the alkoxysilane (a3) include N-2- (aminoethyl) -3-aminopropyltriethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane, and N-phenyl-γ-. Aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-γ-trimethoxysilylpropyl-m-phenylenediamine, N, N-bis [3- (trimethoxysilyl) propyl] ethylenediamine, N- (2- Alkoxysilanes having amino groups such as aminoethyl) -γ-aminopropylmethyldimethoxysilane, p- [N- (2-aminoethyl) aminomethyl] phenethyltrimethoxysilane; isocyanatopropyltrimethoxysilane, isocyanatopropyltri Ethoxysilane, isocyanatoethyl Triethoxysilane, an alkoxysilane having an isocyanate group such as isocyanatomethyl triethoxysilane can be used.

  Among these, as the alkoxysilane (a3), it is possible to use N-2- (aminoethyl) -3-aminopropyltriethoxysilane, and the coating film has excellent warm water resistance, corrosion resistance, and chemical resistance. Is preferable in forming.

  The alkoxysilane (a3) is used in the range of 0.1% by mass to 10% by mass with respect to the total amount of raw materials used for the production of the urethane resin (A), and has excellent hot water resistance, corrosion resistance, and It is preferable when forming a coating film excellent in chemical resistance.

  The reaction of the polyol (a1) and the polyisocyanate (a2) in the step [1] that can constitute the production step of the urethane resin (A) is performed, for example, in the absence of a solvent or in the presence of an organic solvent. (A1) and the said polyisocyanate (a2) can be mixed and it can carry out in reaction temperature range of about 50 to 150 degreeC.

  In the reaction of the polyol (a1) and the polyisocyanate (a2), for example, the equivalent ratio of the isocyanate group of the polyisocyanate (a2) to the hydroxyl group of the polyol (a1) is in the range of 0.8 to 2.5. Preferably, it is carried out in the range of 0.9 to 1.5.

  Moreover, when manufacturing the urethane resin (A ') which has an isocyanate group at the terminal manufactured at the above-mentioned process [1], in order to improve the durability of the coating film, the polyol (a1) and the polyisocyanate ( In addition to a2), a chain extender can be used as necessary.

  As a chain extender that can be used in producing the urethane resin (A ′), polyamine, hydrazine compounds, other active hydrogen atom-containing compounds, and the like can be used.

  Examples of the polyamine include ethylenediamine, 1,2-propanediamine, 1,6-hexamethylenediamine, piperazine, 2,5-dimethylpiperazine, isophoronediamine, 4,4′-dicyclohexylmethanediamine, and 3,3′-. Diamines such as dimethyl-4,4′-dicyclohexylmethanediamine, 1,4-cyclohexanediamine; N-hydroxymethylaminoethylamine, N-hydroxyethylaminoethylamine, N-hydroxypropylaminopropylamine, N-ethylaminoethylamine, N -Methylaminopropylamine; diethylenetriamine, dipropylenetriamine, triethylenetetramine and the like can be used.

  Examples of the hydrazine compound include hydrazine, N, N′-dimethylhydrazine, 1,6-hexamethylenebishydrazine; succinic acid dihydrazide, adipic acid dihydrazide, glutaric acid dihydrazide, sebacic acid dihydrazide, isophthalic acid dihydrazide; β-semicarbazide propion Acid hydrazide or the like can be used.

  Examples of the other active hydrogen-containing compounds include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, hexamethylene glycol, saccharose, Glycols such as methylene glycol, glycerin and sorbitol; bisphenol A, 4,4′-dihydroxydiphenyl, 4,4′-dihydroxydiphenyl ether, 4,4′-dihydroxydiphenyl sulfone, hydrogenated bisphenol A, phenol such as hydroquinone, and water Etc. can be used alone or in combination of two or more within a range in which the storage stability of the aqueous resin composition of the present invention does not decrease.

  Examples of the organic solvent that can be used in producing the urethane resin (A ′) by the step [1] include ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran and dioxane; acetate esters such as ethyl acetate and butyl acetate; Nitriles such as acetonitrile; amides such as dimethylformamide and N-methylpyrrolidone can be used alone or in combination of two or more. When the organic solvent is used when the urethane resin (A) is produced, from the viewpoint of reducing the environmental load, etc., during or after the production of the urethane resin (A), by a distillation method or the like as necessary. It is preferable to remove the organic solvent.

  Moreover, the said process [2] which can comprise the manufacturing process of the said urethane resin (A) mixes and reacts the urethane resin (A ') obtained by the said process [1], and the said alkoxysilane (a3). It is a process. The step [2] is preferably performed, for example, in a reaction temperature range of 20 ° C to 80 ° C.

  Moreover, as said urethane resin (A), the polyol (a1) containing the diol (a1-1) which has the said polymerizable unsaturated group, the said polyisocyanate (a2), and the alkoxy which has an amino group or an isocyanate group. Urethane resin (A'-1) obtained by reacting with silane (a3), and urethane resin (A-) obtained by reacting polysiloxane (X) having a hydrolyzable silyl group or silanol group 1) can be used. By using the urethane resin (A-1), it becomes possible to form a coating film that is more excellent in terms of coating film hardness and weather resistance. Examples of the urethane resin (A-1) include those in which a segment derived from the polysiloxane (X) is included in a segment derived from the urethane resin (A′-1).

  As said urethane resin (A-1), the hydrolyzable silyl group or silanol group which said urethane resin (A'-1) has, and the hydrolyzable silyl group or silanol group which said polysiloxane (X) has. The urethane resin obtained by making it react can be used.

  As the polysiloxane (X), condensates of various alkoxysilanes can be used.

  Examples of the alkoxysilane include tetramethoxysilane, tetraethoxysilane, tetrapropoxysilane, tetraisopropoxysilane, tetrabutoxysilane, “MEK-ST” and “IPA-ST” (manufactured by Nissan Chemical Industries, Ltd.). Tetraalkoxysilane, methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, n-propyltrimethoxysilane represented by organosilica sol , N-propyltriethoxysilane, isopropyltrimethoxysilane, isopropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropyltriethoxysilane, phenyl It can be used dimethyldimethoxysilane, dimethyldiethoxysilane, diethyl dimethoxysilane, dialkoxysilane such as diethyl diethoxy silane; trimethoxysilane, trialkoxysilane such as phenyltriethoxysilane.

  As the polysiloxane (X), a polymer in which a segment composed of a vinyl polymer and a segment composed of a polysiloxane are bonded can be used.

  Examples of the polymer include vinyl monomers such as methyl (meth) acrylate and ethyl (meth) acrylate, and 3- (meth) acryloxypropyltrimethoxysilane and (meth) acryloxypropyltriethoxysilane. A polymer obtained by polymerizing a vinyl monomer having a siloxane structure, a polymer obtained by condensing the alkoxysilane thereto, and the like can be used.

  A polymer composed of a segment composed of a vinyl polymer and a segment composed of a polysiloxane, for example, sequentially supplies the alkoxysilane under an organic solvent solution of a vinyl polymer having a hydrolyzable silyl group. Alternatively, it is supplied in a lump and is carried out in the range of 20 to 120 ° C. for about 0.5 to 24 hours with stirring to hydrolyze the hydrolyzable silyl group of the vinyl polymer and the hydrolyzable silyl group of alkoxysilane. It can be produced by a decomposition condensation reaction.

  As the polysiloxane (X), the urethane resin (A-1) forms a strong polysiloxane-polyurethane structure having a higher crosslinking density, and forms a coating film having excellent warm water resistance, corrosion resistance, and chemical resistance. In doing so, it is preferable to use one having a polymerizable unsaturated group. When polysiloxane (X) having a polymerizable unsaturated group is used, alkoxy containing 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropyltriethoxysilane or the like is used. Preference is given to using condensates of silane mixtures.

  The polymerizable unsaturated group is preferably present in the range of 0.2 mmol / g to 3 mmol / g with respect to the entire polysiloxane (X).

  In addition, the urethane resin composition of the present invention neutralizes part or all of the hydrophilic group of the urethane resin (A) such as the urethane resin (A-1) obtained by the above method, and then includes It can be produced by mixing the hydrate and the aqueous medium (B).

  Examples of the aqueous medium (B) 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-propanol and isopropanol; ketones such as acetone and methyl ethyl ketone; polyalkylene glycols such as ethylene glycol, diethylene glycol and propylene glycol; alkyl ethers of polyalkylene glycols 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 aqueous resin composition of the present invention obtained by the above method contains the urethane resin (A) in the range of 5% by mass to 85% by mass with respect to the total amount of the aqueous resin composition. Preferably, it is contained in the range of 15% by mass to 50% by mass. In addition, the aqueous resin composition of the present invention obtained by the above method uses the aqueous medium (B) containing the aqueous medium (B) in a range of 10% by mass to 90% by mass with respect to the total amount of the aqueous resin composition. It is preferable that it is contained in the range of 45% by mass to 80% by mass.

  The aqueous resin composition preferably uses a polymerization initiator in order to advance radical polymerization by the polymerizable unsaturated double bond of the urethane resin (A).

  As the polymerization initiator, for example, benzophenone, benzyl, Michler ketone, thioxanthone, anthraquinone, benzoin, dialkoxyacetophenone, acyloxime ester, benzyl ketal, hydroxyalkylphenone, halogenoketone and the like can be used. The photopolymerization initiator may be used in combination with a tertiary amine such as methylamine, diethanolamine, N-methyldiethanolamine, or tributylamine as necessary.

  Examples of the polymerization initiator include 2,2′-azobis (2-methylpropionamidine) dihydrochloride, 4,4′-azobis (4-cyano) valeric acid, 2,2′-azobis (2-amidino). Propane) dihydrochloride, benzoyl peroxide, t-butyl hydroperoxide, thermal polymerization initiators such as peroxides such as hydrogen peroxide can also be used.

  The polymerization initiator is preferably used in the range of 0.5% by mass to 5% by mass with respect to the solid content of the urethane resin (A).

  As said aqueous resin composition, what contains said polysiloxane (X) can be used for the purpose of improving a coating-film hardness and a weather resistance further. In such a case, the polysiloxane (X) may be mixed with the urethane resin (A) in the aqueous medium (B) independently of the urethane resin (A). The polysiloxane (X) may be included in the urethane resin (A) particles.

  When mixing and using the said polysiloxane (X) and the said urethane resin (A), the said polysiloxane (X) is the range of 5 mass%-70 mass% with respect to the whole quantity of the said urethane resin (A). It is preferable that the coating film is hard and brittle while improving the coating film hardness and weather resistance.

  In addition to the above-described ones, the aqueous resin composition may inhibit, for example, a film forming aid, a filler, a thixotropic agent, a tackifier, a pigment, an antibacterial agent, and the like. Can be used in the range not to.

  Examples of the film forming aid include, but are not limited to, an anionic surfactant (dioctyl sulfosuccinate soda salt, etc.), a hydrophobic nonionic surfactant (sorbitan monooleate, etc.), silicone oil, and the like.

  Examples of the thixotropy-imparting agent include fatty acid, fatty acid metal salt, fatty acid ester, paraffin, resin acid, surfactant, polyacrylic acid and the like surface-treated filler, polyvinyl chloride powder, hydrogenated castor oil, Fine powder silica, organic bentonite, sepiolite and the like can be mentioned.

  As the pigment, known and commonly used inorganic pigments and organic pigments can be used.

  As the inorganic pigment, for example, titanium oxide, antimony red, bengara, cadmium red, cadmium yellow, cobalt blue, bitumen, ultramarine, carbon black, graphite and the like can be used.

  Examples of the organic pigment include quinacridone pigment, quinacridone quinone pigment, dioxazine pigment, phthalocyanine pigment, anthrapyrimidine pigment, ansanthrone pigment, indanthrone pigment, flavanthrone pigment, perylene pigment, diketopyrrolopyrrole pigment, perinone pigment, Organic pigments such as quinophthalone pigments, anthraquinone pigments, thioindigo pigments, benzimidazolone pigments, and azo pigments can be used. Two or more kinds of these pigments can be used in combination. These pigments may be surface-treated and have a self-dispersing ability with respect to an aqueous medium.

  As the antibacterial agent, for example, silver chloride, trifuranide, dichlorofluanide, fluorophorpet, zinc pyrithione, methyl 2-benzimidazole carbanate, 2- (4-thiazolyl) benzimidazole and the like can be used.

  Examples of other additives include reaction accelerators (metal reaction accelerators, metal salt reaction accelerators, amine reaction accelerators, etc.), stabilizers (ultraviolet absorbers, antioxidants, heat stabilizers, etc.). , Various additives such as a moisture removing agent (4-paratoluenesulfonyl isocyanate, etc.), an adsorbent (quick lime, slaked lime, zeolite, molecular sieve, etc.), an adhesion-imparting agent, an antifoaming agent, and a leveling agent.

  The aqueous resin composition of the present invention can be suitably used, for example, as a coating agent that can impart surface protection and design properties to various substrates.

  As a base material which can apply | coat the said coating agent and can form a coating film, a glass base material, a metal base material, a plastic base material, paper, a wood base material, a fibrous base material etc. are mentioned, for example. Moreover, the base material of porous body structures, such as a urethane foam, can also be used.

  Examples of plastic base materials include polycarbonate base materials, polyester base materials, acrylonitrile-butadiene-styrene base materials, polyacryl base materials, polystyrene base materials, polyurethane base materials, epoxy resin base materials, polyvinyl chloride base materials, and polyamide base materials. Can be used.

  As said metal base material, galvanized steel plates, such as a galvanized steel plate and an aluminum zinc alloy steel plate, an iron plate, an aluminum plate, an aluminum alloy plate, an electromagnetic steel plate, a copper plate, a stainless steel plate etc. can be used, for example.

  The base material may be a planar material made of the above material or may have a curved portion, or may be a base material made of fibers such as a nonwoven fabric.

  The coating agent of the present invention is, for example, applied directly to the surface of the base material or the surface of the base material on which a primer layer or the like is previously provided, and then dried, and then the polymerization of the urethane resin (A) A coating film can be formed by advancing radical polymerization of a polymerizable unsaturated double bond.

  In addition, a coating film is formed on the surface of the release paper by applying the coating agent on the release paper, then drying and curing, and a non-woven fabric obtained by applying an adhesive or an adhesive on the coating film. A film formed using the coating agent can be laminated on the surface of a desired substrate by laminating the substrate made of such fibers and peeling the release paper.

  Examples of the method for applying the coating agent on the substrate include a spray method, a curtain coater method, a flow coater method, a roll coater method, a brush coating method, and a dipping method.

  Examples of the method for curing the coating agent include a heating method and a method of irradiating active energy rays such as ultraviolet rays.

  The heating method varies depending on the type of radical polymerization initiator to be used, but the radical polymerization can be progressed and cured, for example, by performing it at a temperature of about 100 ° C. to 150 ° C. for about 10 minutes to 30 minutes. .

  Examples of the method of irradiating the active energy ray include a method using a known lamp such as a xenon lamp, a xenon-mercury lamp, a metal halide lamp, a high-pressure mercury lamp, a low-pressure mercury lamp, and an LED lamp in the case of ultraviolet rays. It is done.

The exposure dose of the actinic energy ray ^is preferably in the range of ^{50mJ / cm 2 ~5,000mJ / cm 2} , more preferably in the range of ^{100mJ / cm 2 ~3,000mJ / cm 2} , 100mJ / A range of cm ^{2 to} 1000 mJ / cm ² is particularly preferable. In addition, said ultraviolet irradiation amount is based on the value measured in the wavelength range of 300 nm-390 nm using UV checker UVR-N1 (made by Nippon Battery Co., Ltd.).

  Although the thickness of the coating film that can be formed using the coating agent of the present invention can be appropriately adjusted according to the use of the substrate, it is usually preferably about 0.1 μm to 20 μm.

  As described above, articles provided with a coating formed on the base material using the coating agent are used as metal products such as mobile phones, various plastic products such as home appliances, automobile exteriors, and building materials. Is possible.

  Hereinafter, the present invention will be specifically described by way of examples and comparative examples.

[Preparation Example 1]
In a reaction vessel equipped with a stirrer, a thermometer, a dropping funnel, a cooling pipe, and a nitrogen gas inlet, 200 parts by mass of phenyltrimethoxysilane was charged and heated to 120 ° C.

  Next, a mixture containing 150 parts by weight of methyl methacrylate, 15 parts by weight of 3-methacryloxypropyltrimethoxysilane, and 20 parts by weight of tert-butylperoxy-2-ethylhexanoate was added into the reaction vessel for 4 hours. It was dripped over. Then, it stirred at the same temperature for 16 hours, and prepared the vinyl polymer (Y-1) which has a trimethoxysilyl group.

  Next, the temperature of the reaction vessel was adjusted to 80 ° C., and 970 parts by mass of methyltrimethoxysilane, 416 parts by mass of 3-acryloyloxypropyltrimethoxysilane, and 200 parts by mass of dimethyldimethoxysilane were added to the reaction vessel. .

  Thereafter, a mixture of 20 parts by mass of “A-3” (iso-propyl acid phosphate, manufactured by Sakai Chemical Co., Ltd.) and 300 parts by mass of water is added dropwise over 5 minutes, and stirred at the same temperature for 2 hours. The reaction product was obtained by hydrolysis and condensation reaction.

When the reaction product was analyzed by ¹ H-NMR, almost 100% of the trimethoxysilyl group of the vinyl polymer (Y-1) was hydrolyzed.

  Thereafter, the reaction product was distilled under a reduced pressure of 10 to 300 mmHg for 2 hours under conditions of 40 to 60 ° C. to remove methanol and water, thereby removing vinyl heavy having a non-volatile content of 99.6% by mass. Polysiloxane (X-1) in which the coalesced segment and the polysiloxane segment were bonded was obtained.

[Example 1]
Polyester polyol (number average molecular weight 2,000) obtained by reacting 1,6-hexanediol, neopentyl glycol and adipic acid in a nitrogen-substituted container equipped with a thermometer, a nitrogen gas inlet tube, and a stirrer ) 100 parts by weight, 19 parts by weight of 1,4-cyclohexanedimethanol, 20 parts by weight of 2,2-dimethylolpropionic acid, 65 parts by weight of a reaction product of 1,6-hexanediol diglycidyl ether and acrylic acid, , 174 parts by mass of dicyclohexylmethane diisocyanate is mixed with 126 parts by mass of methyl ethyl ketone, and reacted under conditions of a temperature of 80 ° C. in the reaction vessel, thereby having a polymerizable unsaturated bond in the side chain, An organic solvent solution of urethane resin having an isocyanate group at the terminal was obtained.

  Next, the organic solvent solution, 17 parts by mass of N-2- (aminoethyl) -3-aminopropyltriethoxysilane, and 358 parts by mass of methyl ethyl ketone are mixed, and the temperature in the reaction vessel is adjusted to 50 ° C. By making it react, the organic solvent solution of the urethane resin (A1-1) which has a hydrolysable silyl group or silanol group, and a polymerizable unsaturated group was obtained.

  Next, after mixing the organic solvent solution of the urethane resin (A1-1) and 13 parts by mass of dimethylethanolamine, 1069 parts by mass of water was added and sufficiently stirred, and 71 parts by mass of 10% by mass of piperazine aqueous solution was added. In addition, an aqueous resin composition (1) composed of an aqueous dispersion of a urethane resin (A1) having a nonvolatile content of 30% by mass was obtained by subjecting it to chain elongation reaction and distillation under reduced pressure.

[Example 2]
After mixing the total amount of the organic solvent solution of the urethane resin (A1-1), 396 parts by mass of the polysiloxane (X-1) obtained in Preparation Example 1, and 13 parts by mass of dimethylethanolamine, 1717 parts by mass of water. An aqueous solution comprising an aqueous dispersion of a urethane resin (A2) having a nonvolatile content of 45% by mass is subjected to a chain extension reaction by adding 71 parts by mass of a 10% by mass piperazine aqueous solution and distilled under reduced pressure. A resin composition (2) was obtained.

Example 3
Polyester polyol (number average molecular weight 2,000) obtained by reacting 1,6-hexanediol, neopentyl glycol and adipic acid in a nitrogen-substituted container equipped with a thermometer, a nitrogen gas inlet tube, and a stirrer ) 100 parts by weight, 19 parts by weight of 1,4-cyclohexanedimethanol, 20 parts by weight of 2,2-dimethylolpropionic acid, 65 parts by weight of a reaction product of 1,6-hexanediol diglycidyl ether and acrylic acid, , 174 parts by mass of dicyclohexylmethane diisocyanate is mixed with 126 parts by mass of methyl ethyl ketone, and reacted under conditions of a temperature of 80 ° C. in the reaction vessel, thereby having a polymerizable unsaturated bond in the side chain, An organic solvent solution of urethane resin having an isocyanate group at the terminal was obtained.

  Next, the organic solvent solution was mixed with 17 parts by mass of N-2- (aminoethyl) -3-aminopropyltriethoxysilane, 37 parts by mass of 3-aminopropyltriethoxysilane, and 402 parts by mass of methyl ethyl ketone, By adjusting the temperature in the reaction vessel to 50 ° C. and reacting, an organic solvent solution of urethane resin (A3-1) having a hydrolyzable silyl group or silanol group and a polymerizable unsaturated group was obtained.

  Next, the total amount of the organic solvent solution of the urethane resin (A3-1) and 433 parts by mass of the polysiloxane (X-1) obtained in Preparation Example 1 were mixed, and “A-3” at 70 ° C. [The urethane resin is produced by dripping a mixture of 1 part by mass of iso-propyl acid phosphate manufactured by Sakai Chemical Co., Ltd. and 12.5 parts by mass of water over 5 minutes and further reacting at the same temperature for 3 hours. An organic solvent solution of urethane resin (A3-2) obtained by hydrolytic condensation of (A3-1) and polysiloxane (X-1) was obtained.

  Next, after mixing the total amount of the organic solvent solution of the urethane resin (A3-2) and 13 parts by mass of dimethylethanolamine, 1951 parts by mass of water was added and stirred sufficiently, followed by distillation under reduced pressure. An aqueous resin composition (3) comprising an aqueous dispersion of a urethane resin (A3) having a content of 45% by mass was obtained.

Example 4
In the same manner as in Example 1 except that 51 parts by mass of pentaerythritol diacrylate was used instead of 65 parts by mass of the reaction product of 1,6-hexanediol diglycidyl ether and acrylic acid, a urethane resin (A4- The aqueous resin composition (4) comprising the aqueous dispersion of the urethane resin (A4) having a nonvolatile content of 30% by mass is synthesized by synthesizing the organic solvent solution of 1), water dispersion, chain extension reaction, and distillation under reduced pressure. Obtained.

Example 5
After mixing the total amount of the organic solvent solution of the urethane resin (A4-1), 382 parts by mass of the polysiloxane (X-1) obtained in Preparation Example 1, and 13 parts by mass of dimethylethanolamine, 1655 parts by weight of water. An aqueous solution composed of an aqueous dispersion of a urethane resin (A5) having a nonvolatile content of 45% by mass is subjected to a chain extension reaction by adding 71 parts by mass of a 10% by mass piperazine aqueous solution and distilled under reduced pressure. A resin composition (5) was obtained.

Example 6
In the same manner as in Example 3 except that 51 parts by mass of pentaerythritol diacrylate was used instead of 65 parts by mass of the reaction product of 1,6-hexanediol diglycidyl ether and acrylic acid, a urethane resin (A6- The organic solvent solution of 1) was synthesized.

Next, the total amount of the organic solvent solution of the urethane resin (A6-1) and 419 parts by mass of the polysiloxane (X-1) obtained in Preparation Example 1 were mixed, and “A-3” at 70 ° C. [The urethane resin is produced by dripping a mixture of 1 part by mass of iso-propyl acid phosphate manufactured by Sakai Chemical Co., Ltd. and 12.5 parts by mass of water over 5 minutes and further reacting at the same temperature for 3 hours. An organic solvent solution of urethane resin (A6-2) obtained by hydrolytic condensation of (A6-1) and polysiloxane (X-1) was obtained.
Next, after the total amount of the organic solvent solution of the urethane resin (A6-2) and 13 parts by mass of dimethylethanolamine were mixed, 1888 parts by mass of water was added, and the mixture was sufficiently stirred and distilled under reduced pressure. An aqueous resin composition (6) comprising an aqueous dispersion of a urethane resin (A6) having a content of 45% by mass was obtained.

Example 7
Polyester polyol (number average molecular weight 2,000) obtained by reacting 1,6-hexanediol, neopentyl glycol and adipic acid in a nitrogen-substituted container equipped with a thermometer, a nitrogen gas inlet tube, and a stirrer ) 10 parts by mass, 6 parts by mass of 2,2-dimethylolpropionic acid, 61 parts by mass of pentaerythritol diacrylate, and 72 parts by mass of dicyclohexylmethane diisocyanate are mixed in 50 parts by mass of methyl ethyl ketone, The organic solvent solution of the urethane resin which has a polymerizable unsaturated bond in a side chain and has an isocyanate group at the terminal of the main chain was obtained by reacting at a temperature of 80 ° C.

  Next, the organic solvent solution, 3 parts by mass of N-2- (aminoethyl) -3-aminopropyltriethoxysilane, and 178 parts by mass of methyl ethyl ketone are mixed, and the temperature in the reaction vessel is adjusted to 50 ° C. By making it react, the organic solvent solution of the urethane resin (A7-1) which has a hydrolysable silyl group or a silanol group, and a polymerizable unsaturated group was obtained.

  Next, after mixing the total amount of the organic solvent solution of the urethane resin (A7-1), 15 parts by mass of the polysiloxane (X-1) obtained in Preparation Example 1, and 4 parts by mass of dimethylethanolamine, An aqueous dispersion of a urethane resin (A7) having a nonvolatile content of 35% by mass by adding 448 parts by mass of water, sufficiently stirring, 11 parts by mass of a 10% by mass aqueous piperazine solution, causing chain extension reaction, and distillation under reduced pressure. An aqueous resin composition (7) was obtained.

Example 8
Polyester polyol (number average molecular weight 2,000) obtained by reacting 1,6-hexanediol, neopentyl glycol and adipic acid in a nitrogen-substituted container equipped with a thermometer, a nitrogen gas inlet tube, and a stirrer ) 10 parts by mass, 9 parts by mass of 2,2-dimethylolpropionic acid, 9 parts by mass of pentaerythritol diacrylate, and 35 parts by mass of dicyclohexylmethane diisocyanate are mixed in 21 parts by mass of methyl ethyl ketone, The organic solvent solution of the urethane resin which has a polymerizable unsaturated bond in a side chain and has an isocyanate group at the terminal of the main chain was obtained by reacting at a temperature of 80 ° C.

  Next, the organic solvent solution, 9 parts by mass of N-2- (aminoethyl) -3-aminopropyltriethoxysilane, and 193 parts by mass of methyl ethyl ketone are mixed, and the temperature in the reaction vessel is adjusted to 50 ° C. By making it react, the organic solvent solution of the urethane resin (A8-1) which has a hydrolysable silyl group or a silanol group, and a polymerizable unsaturated group was obtained.

  Next, after mixing the total amount of the organic solvent solution of the urethane resin (A8-1), 286 parts by mass of the polysiloxane (X-1) obtained in Preparation Example 1, and 6 parts by mass of dimethylethanolamine, 907 parts by mass of water was added, and the mixture was sufficiently stirred and distilled under reduced pressure to obtain an aqueous resin composition (8) comprising an aqueous dispersion of a urethane resin (A8) having a nonvolatile content of 45% by mass.

[Comparative Example 1]
Polyester polyol (number average molecular weight 2,000) obtained by reacting 1,6-hexanediol, neopentyl glycol and adipic acid in a nitrogen-substituted container equipped with a thermometer, a nitrogen gas inlet tube, and a stirrer ) 100 parts by weight, 7 parts by weight of 1,4-cyclohexanedimethanol, 5.5 parts by weight of 2,2-dimethylolpropionic acid, 1 part by weight of trimethylolpropane, and 60 parts by weight of dicyclohexylmethane diisocyanate, It mixed with 58 mass parts of methyl ethyl ketone, and was made to react on the conditions of the temperature of 80 degreeC in the said reaction container, and the organic solvent solution of the urethane prepolymer which has an isocyanate group at the terminal was obtained.

  Next, an organic solvent solution of the urethane prepolymer and 3 parts by mass of 2-hydroxyethyl acrylate are mixed and reacted under the condition of a temperature of 80 ° C. in the reaction vessel, whereby a polymerizable chain is not introduced into the side chain. An organic solvent solution of a urethane resin having a saturated bond and having an isocyanate group at the end of the main chain was obtained.

  Next, an organic solvent solution of the urethane resin, 5 parts by mass of N-2- (aminoethyl) -3-aminopropylmethyltriethoxysilane, and 163 parts by mass of methyl ethyl ketone are mixed, and the temperature in the reaction vessel is set to 50. An organic solvent solution of a urethane resin (A1′-1) having a hydrolyzable silyl group or silanol group and a polymerizable unsaturated group was obtained by adjusting the reaction to ° C.

  Next, after mixing the organic solvent solution of the urethane resin (A1′-1) and 4 parts by mass of dimethylethanolamine, 480 parts by mass of water was added and sufficiently stirred, and 46% by mass of 10% by mass of piperazine aqueous solution was added. An aqueous resin composition (1 ′) composed of an aqueous dispersion of a urethane resin (A1 ′) having a nonvolatile content of 30% by mass was obtained by adding a part and subjecting it to chain elongation reaction and distillation under reduced pressure.

[Comparative Example 2]
After mixing the total amount of the organic solvent solution of the urethane resin (A1′-1), 181 parts by mass of the polysiloxane (X-1) obtained in Preparation Example 1, and 4 parts by mass of dimethylethanolamine, water 774 is mixed. From the aqueous dispersion of urethane resin (A2 ′) having a non-volatile content of 45% by mass, adding 46 parts by mass of 10% by mass of piperazine aqueous solution and subjecting it to chain extension reaction by distillation under reduced pressure. An aqueous resin composition (2 ′) was obtained.

[Evaluation of corrosion resistance]
Formulation obtained by blending 4 parts by mass of a photopolymerization initiator (a mixture of 1-hydroxy-cyclohexyl-phenyl-ketone and benzophenone) with respect to 100 parts by mass of the solid content of the aqueous resin compositions obtained in Examples and Comparative Examples. The solution was applied to a 55% by mass aluminum-zinc alloy-plated steel plate degreased with acetone so that the film thickness after drying would be about 1 μm using a bar coater, and placed in a dryer at an ambient temperature of 100 ° C. for 30 seconds. The coated film was prepared by applying and drying 500 mJ / cm ² using a high pressure mercury lamp. Then, what was cured at room temperature for 3 days was used as a test piece.

  The surface of the coating film constituting the test piece is scratched with a cutter knife to a depth reaching the base material (cross cut part), and a salt spray test is carried out with a salt spray tester manufactured by Suga Test Instruments Co., Ltd. The area where rust was generated after 240 hours was visually determined and evaluated. The evaluation was performed separately for a flat portion not damaged by the cutter knife and a peripheral portion of the cross cut portion.

<Plane>
(Double-circle): The area where the generation | occurrence | production of rust and the swelling and peeling of the coating film resulting from rust were less than 5% with respect to the whole plane part.

  ◯: The area where the occurrence of rust and the swelling or peeling of the coating film due to rust occurred was 5% or more and less than 30% with respect to the entire plane portion.

  (Triangle | delta): The area where the generation | occurrence | production of rust and the swelling and peeling of the coating film resulting from rust were 30% or more and less than 60% with respect to the whole plane part.

  X: The area where the occurrence of rust and the swelling and peeling of the coating film due to rust occurred was 60% or more with respect to the entire plane portion.

<The peripheral part of the crosscut part>
(Double-circle): Generation | occurrence | production of rust was not seen in the peripheral part of a crosscut part, and peeling of the coating film etc. resulting from rust was not seen.

  ◯: A very small amount of rust was observed in the periphery of the crosscut part, but no peeling or swelling of the coating film due to it was observed.

  Δ: Rust was widely observed in the periphery of the crosscut portion, and although peeling or swelling of the coating film was observed due to this, no flow rust was observed.

  X: Rust was widely generated in the periphery of the crosscut part, and peeling and swelling of the coating film due to the rust were observed. Further, contamination of the coating film due to flowing rust was observed.

[Method for evaluating hot water resistance]
Formulation obtained by blending 4 parts by mass of a photopolymerization initiator (a mixture of 1-hydroxy-cyclohexyl-phenyl-ketone and benzophenone) with respect to 100 parts by mass of the solid content of the aqueous resin compositions obtained in Examples and Comparative Examples. The solution was applied to a 55% by mass aluminum-zinc alloy-plated steel plate degreased with acetone so that the film thickness after drying would be about 1 μm using a bar coater, and 30% in a dryer having an atmospheric temperature of 100 ° C. The coating film was created by putting in and drying for 2 seconds, and also irradiating 500 mJ / cm < ² > using a high pressure mercury lamp. Then, what was cured at room temperature for 3 days was used as a test piece. The said test piece was immersed in 60 degreeC warm water, and the deterioration state of the coating film 60 minutes after was observed.

  A: There was no change in the coating film.

  ○: Slight discoloration was observed on a very small part of the coating film surface, but it was at a level causing no practical problems.

  Δ: Swelling or the like was observed in the entire coating film.

  X: The coating film peeled and the base material was exposed.

[Chemical resistance (acid resistance) evaluation method]
Formulation obtained by blending 4 parts by mass of a photopolymerization initiator (a mixture of 1-hydroxy-cyclohexyl-phenyl-ketone and benzophenone) with respect to 100 parts by mass of the solid content of the aqueous resin compositions obtained in Examples and Comparative Examples. The solution was applied to a 55% by mass aluminum-zinc alloy-plated steel plate degreased with acetone so that the film thickness after drying would be about 1 μm using a bar coater, and 30% in a dryer having an atmospheric temperature of 100 ° C. The coating film was created by putting in and drying for 2 seconds, and also irradiating 500 mJ / cm < ² > using a high pressure mercury lamp. Then, what was cured at room temperature for 3 days was used as a test piece. 1N hydrochloric acid was spotted on the surface of the coating film constituting the test piece, and the deterioration state of the coating film after standing for 180 minutes was observed.

  A: There was no change on the surface of the coating film.

  A: Some yellowing was observed on the surface of the coating film, but it was at a level where there was no practical problem.

  (Triangle | delta): The surface of the coating film changed remarkably.

  X: The coating film melt | dissolved and the base material was exposed.

[Evaluation method for chemical resistance (alkali resistance)]
Formulation obtained by blending 4 parts by mass of a photopolymerization initiator (a mixture of 1-hydroxy-cyclohexyl-phenyl-ketone and benzophenone) with respect to 100 parts by mass of the solid content of the aqueous resin compositions obtained in Examples and Comparative Examples. The solution was applied to a 55% by mass aluminum-zinc alloy-plated steel plate degreased with acetone so that the film thickness after drying would be about 1 μm using a bar coater, and placed in a dryer at an ambient temperature of 100 ° C. for 30 seconds. The coated film was prepared by applying and drying 500 mJ / cm ² using a high pressure mercury lamp. Then, what was cured at room temperature for 3 days was used as a test piece.

  A 5% by mass aqueous sodium hydroxide solution was spotted on the surface of the coating film constituting the test piece, and the deterioration state of the coating film after standing for 20 minutes was observed.

  A: There was no change on the surface of the coating film.

  ○: Some discoloration was observed on a part of the surface of the coating film, but it was at a level where there was no practical problem.

  Δ: Discoloration was observed on the surface of the coating film.

  X: The coating film melt | dissolved and the base material was exposed.

[Adhesion to substrate (primary adhesion)]
Formulation obtained by blending 4 parts by mass of a photopolymerization initiator (a mixture of 1-hydroxy-cyclohexyl-phenyl-ketone and benzophenone) with respect to 100 parts by mass of the solid content of the aqueous resin compositions obtained in Examples and Comparative Examples. The solution was applied on each substrate shown below using a 3 mil applicator, dried at 60 ° C. for 30 minutes, further irradiated with 500 mJ / cm ² using a high-pressure mercury lamp, and then cured at 25 ° C. for 2 days. A coating film was prepared. On the surface of the obtained coating film, a cellophane (registered trademark) peel test of 100 square 1 mm squares was carried out according to JIS K-5400. The number of grids not peeled was measured and evaluated according to the following criteria. As the substrate, a substrate made of polyethylene terephthalate resin and a glass substrate were used.

  A: The number of grids not peeled is 90 or more.

  ○: The number of grids not peeled is 60 or more and less than 90.

  (Triangle | delta): The number of grids which do not peel is 40 or more and less than 60.

  X: The number of grids which do not peel is less than 40.

[Adhesion to substrate (hot water adhesion)]
The test piece consisting of the same coating film as in the primary adhesion test was immersed in warm water at 50 ° C. for 5 hours, then taken out, and the adhesion of the surface wiped off was determined by the same peel test method as the primary adhesion test. evaluated.

  A: The number of grids not peeled is 90 or more.

  ○: The number of grids not peeled is 60 or more and less than 90.

  (Triangle | delta): The number of grids which do not peel is 40 or more and less than 60.

  X: The number of grids which do not peel is less than 40.

  The “polyester polyol” in Tables 1 and 2 refers to a polyester polyol (number average molecular weight 2,000) obtained by reacting 1,6-hexanediol, neopentyl glycol and adipic acid.

Claims (7)

It contains a urethane resin (A) having a hydrolyzable silyl group or silanol group and a polymerizable unsaturated group, and an aqueous medium (B), and the urethane resin (A) has a polymerizable unsaturated group. It is obtained by reacting a polyol (a1) containing a diol (a1-1), a polyisocyanate (a2), and an alkoxysilane (a3) having an amino group or an isocyanate group. An aqueous resin composition. The aqueous resin composition according to claim 1, wherein the urethane resin (A) has a polymerizable unsaturated group in a range of 0.2 mol / kg to 3 mol / kg with respect to the entire urethane resin (A). . The diol (a1-1) having a polymerizable unsaturated group is a reaction product of a compound having two or more epoxy groups and a (meth) acrylic monomer having a carboxyl group, or pentaerythritol diacrylate. The aqueous resin composition according to claim 1. The urethane resin (A) is a polyol (a1) containing a diol (a1-1) having a polymerizable unsaturated group, a polyisocyanate (a2), and an alkoxysilane (a3) having an amino group or an isocyanate group. The urethane resin (A′-1) obtained by reacting with a polysiloxane (X) having a hydrolyzable silyl group or silanol group is obtained by reacting with the urethane resin (A′-1). An aqueous resin composition. The said urethane resin (A) has the structure derived from the said alkoxysilane (a3) in the range of 0.1 mass%-10 mass% with respect to the whole said urethane resin (A). The aqueous resin composition as described. The said urethane resin (A) has an atomic group comprised by an oxygen atom and a silicon atom with respect to the whole said urethane resin (A) in the range of 0.1 mass%-40 mass%. 2. The aqueous resin composition according to 1. An article coated with the aqueous resin composition according to any one of claims 1 to 6.