JP2008308523A - Composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To achieve a composition useful as an aqueous binder of coating material, ink or a viscous adhesive agent, forming a coat film having high hardness, and excellent water resistance and solvent resistance. <P>SOLUTION: This composition contains a water-soluble resin solution (I) obtained by neutralizing a vinyl polymer (A) with a basic compound (B) and a water-insoluble resin dispersion (II), wherein a carboxy group-containing vinyl monomer unit (a) and an epoxy radical-containing vinyl monomer unit (b) are contained as the constitutional unit of the vinyl polymer A, and the molar equivalent ratio of the carboxy group of the carboxy group-containing vinyl monomer unit (a) and the epoxy group of the epoxy radical-containing vinyl monomer unit (b) is carboxy group/epoxy radical=1/30 to 30/1. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a composition, and particularly to a composition suitable as an aqueous binder for paints, inks, adhesives and the like.

  In recent years, water-based paints, inks, and adhesives have been used in the fields of paints, inks, adhesives, etc. due to the growing awareness of the environment, and these binder resins have been developed. Yes.

For example, Patent Document 1 discloses an aqueous vinyl polymer solution obtained by neutralizing an acid group-containing vinyl polymer polymerized by a suspension polymerization method with a basic compound, and an aqueous dispersion represented by an emulsion. An aqueous coating composition containing is disclosed. According to this, the film-forming property and hardness of a coating film are made compatible by combining a vinyl polymer aqueous solution and an aqueous dispersion.
Patent Document 2 discloses an aqueous resin composition containing an aqueous dispersion composed of a specific monomer unit and a water-soluble resin composed of a specific monomer unit.
JP 7-48537 A JP 2006-282808 A

However, the coating film formed from the aqueous coating composition described in Patent Document 1 has water resistance enough to be kept in warm water at 40 ° C. for 2 days, but is kept for several weeks in warm water at 50 ° C. Under more severe conditions, the water resistance was insufficient. Moreover, even near room temperature, it did not have sufficient resistance to solvents such as xylene.
Moreover, in patent document 2, water-soluble resin contained in an aqueous resin composition is manufactured by using a large amount (the same amount as the sum total of the monomer which comprises this water-soluble resin) of hydrophilic organic solvent, and is aqueous. The resin composition was made into an aqueous solution, and the load on the environment could not be reduced sufficiently. Moreover, this water-soluble resin improves adhesiveness with a top coating material and a foundation | substrate, and did not contribute to the improvement of water resistance and solvent resistance of the coating film obtained. Furthermore, the glass transition temperature (Tg) of the water-soluble resin was as low as -20 to -15 ° C, and the hardness of the coating film was not always satisfactory.

  The present invention has been made in view of the above circumstances, and has a composition useful as an aqueous binder for paints, inks, adhesives and the like that can form a coating film having high hardness and excellent water resistance and solvent resistance. It is intended to be realized.

  As a result of intensive studies to solve the above-mentioned object, the present inventors have identified the unit constituting the vinyl polymer used in the water-soluble resin, and without using a large amount of a hydrophilic organic solvent, The present invention has been completed by finding that it is an aqueous binder such as a paint that is high and can form a coating film that is excellent in water resistance and solvent resistance.

That is, the composition of the present invention comprises a water-soluble resin solution (I) obtained by neutralizing a vinyl polymer (A) with a basic compound (B), and a water-insoluble resin dispersion (II). A composition containing, comprising as a constituent unit of the vinyl polymer (A), a carboxyl group-containing vinyl monomer unit (a) and an epoxy group-containing vinyl monomer unit (b). And the molar equivalent ratio of the carboxy group of the carboxyl group-containing vinyl monomer unit (a) and the epoxy group of the epoxy group-containing vinyl monomer unit (b) is carboxyl group / epoxy group = 1. / 30 to 30/1.
The vinyl polymer (A) preferably has a glass transition temperature (Tg) calculated using the following formula (1) of 0 to 150 ° C.
1 / Tg = Σ (w _i / Tg _i ) (1)
Wherein (1), w _i represents the weight fraction of the monomer i which constitutes the polymer, Tg _i represents the glass transition temperature of the homopolymer of the monomer i.
Furthermore, it is preferable that the vinyl polymer (A) is produced by a suspension polymerization method.

  ADVANTAGE OF THE INVENTION According to this invention, a composition useful as aqueous binders, such as a coating material, ink, and an adhesive agent which can form the coating film which is high in hardness and excellent in water resistance and solvent resistance, is realizable.

The present invention will be described in detail below. In the present invention, “cohesiveness, hardness, water resistance, solvent resistance, appearance, initial gloss of the coating film” means paints, inks, adhesives, etc. using the composition of the present invention as an aqueous binder. The adhesion, hardness, water resistance, solvent resistance, appearance, and initial gloss of the coating film formed from
The composition of the present invention contains a water-soluble resin solution (I) obtained by neutralizing a vinyl polymer (A) with a basic compound (B), and a water-insoluble resin dispersion (II). .

[Water-soluble resin solution (I)]
<Vinyl polymer (A)>
The vinyl polymer (A) used in the present invention includes, as a structural unit, a carboxyl group-containing vinyl monomer unit (a) (hereinafter sometimes referred to as “monomer (a)”) and an epoxy. Group-containing vinyl monomer unit (b) (hereinafter sometimes referred to as “monomer (b)”).
Although it does not restrict | limit especially as a monomer (a), For example, (meth) acrylic acid, 2- (meth) acryloyloxyethyl hexahydrophthalic acid, 2- (meth) acryloyloxypropyl hexahydrophthalic acid, 2- (Meth) acryloyloxyethyltetrahydrophthalic acid, 2- (meth) acryloyloxypropyltetrahydrophthalic acid, 5-methyl-2- (meth) acryloyloxyethylhexahydrophthalic acid, 2- (meth) acryloyloxyethylphthalic acid, 2- (meth) acryloyloxypropylphthalic acid, 2- (meth) acryloyloxyethylmaleic acid, 2- (meth) acryloyloxypropylmaleic acid, 2- (meth) acryloyloxyethylsuccinic acid, 2- (meth) acryloyl Oxypropyl succinic acid, 2- Vinyl monomers containing carboxyl groups such as (meth) acryloyloxyethyl oxalic acid, 2- (meth) acryloyloxypropyl oxalic acid, crotonic acid, fumaric acid, maleic acid, itaconic acid, sorbic acid; itaconic anhydride, Examples thereof include carboxylic acid anhydride group-containing vinyl monomers such as maleic anhydride; monoesters of dicarboxylic acids such as monomethyl itaconate. These may be used alone or in combination of two or more. Among these, (meth) acrylic acid is particularly preferable from the viewpoint of good copolymerizability with other vinyl monomers.
“(Meth) acrylic acid” means “acrylic acid and / or methacrylic acid”, and “(meth) acryloyl” means “acryloyl and / or methacryloyl”.

  The content of the monomer (a) is preferably 2 to 40% by mass and more preferably 3 to 30% by mass in 100% by mass of the vinyl polymer (A). When the content is 2% by mass or more, the addition of the basic compound (B) described later improves the water solubility of the vinyl polymer (A), and the adhesion, hardness, and solvent resistance of the coating film. Tend to improve. On the other hand, when the content is 40% by mass or less, when the water-soluble resin solution (I) is obtained, the viscosity tends to be lowered or high solid differentiation tends to occur.

  The monomer (b) is not particularly limited. For example, glycidyl (meth) acrylate, glycidyl α-ethyl acrylate, glycidyl α-n-propyl acrylate, glycidyl α-n-butyl acrylate, (meth ) 3,4-epoxybutyl acrylate, 6,7-epoxyheptyl (meth) acrylate, α-ethyl acrylate 6,7-epoxyheptyl, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinyl benzyl glycidyl ether etc. are mentioned. These may be used alone or in combination of two or more. Among these, glycidyl methacrylate is particularly preferable because it has good copolymerizability with other vinyl monomers.

  The content of the monomer (b) is preferably 0.5 to 50% by mass and more preferably 1 to 40% by mass in 100% by mass of the vinyl polymer (A). If content is 0.5 mass% or more, it exists in the tendency for the hardness of a coating film, water resistance, and solvent resistance to improve. On the other hand, when the content is 50% by mass or less, the appearance and initial gloss of the coating film tend to be improved.

  The mass ratio of the monomer (a) to the monomer (b) is the molar equivalent ratio of the carboxyl group of the monomer (a) to the epoxy group of the monomer (b) (carboxyl group / epoxy group). Is required to be 1/30 to 30/1, and preferably 1/20 to 20/1. When the molar equivalent ratio is 1/30 or more, the adhesion, hardness, water resistance, and solvent resistance of the coating film are improved. On the other hand, when the molar equivalent ratio is 30/1 or less, the appearance and initial gloss of the coating film are improved.

  The vinyl polymer (A) may contain other vinyl monomer units (c) (hereinafter referred to as “monomer (c)”) as necessary, in addition to the monomer units described above. May be included as a constituent component. The monomer (c) is, for example, to relieve the reaction between the carboxyl group of the monomer (a) and the epoxy group of the monomer (b) in the coating film performance modification or polymerization process. It can be used as a purpose.

Although it does not restrict | limit especially as a monomer (c), For example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, i-propyl (meth) acrylate, n-butyl (meth) Acrylate, i-butyl (meth) acrylate, sec-butyl (meth) acrylate, t-butyl (meth) acrylate, n-octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-lauryl (meth) acrylate, n-stearyl (meth) acrylate, cyclohexyl (meth) acrylate, phenyl (meth) acrylate, benzyl (meth) acrylate, isobornyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, Feno Siethyl (meth) acrylate, 2- (2-ethylhexaoxy) ethyl (meth) acrylate, 1-methyl-2-methoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, 3-methyl-3-methoxy Butyl (meth) acrylate, o-methoxyphenyl (meth) acrylate, m-methoxyphenyl (meth) acrylate, p-methoxyphenyl (meth) acrylate, o-methoxyphenylethyl (meth) acrylate, m-methoxyphenylethyl (meta ) Acrylate, p-methoxyphenylethyl (meth) acrylate and other (meth) acrylate monomers; 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate Hydroxyl group-containing (meth) acrylic acid ester monomers such as 2-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and glycerol (meth) acrylate; dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) ) Amino group-containing (meth) acrylic acid ester monomers such as acrylate; Fluorine atom-containing (meth) such as trifluoroethyl (meth) acrylate, pentadecafluorooctyl (meth) acrylate, heptadecafluorodecyl (meth) acrylate Acrylic acid ester monomer; (meth) acrylamide, Nt-butyl (meth) acrylamide, N-methylol (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-butoxymethyl (meth) acrylamide, Amide group-containing monomers such as diacetone acrylamide, maleic acid amide, maleimide; vinyl-based monomers such as styrene, α-methylstyrene, vinyltoluene, (meth) acrylonitrile, vinyl chloride, vinylidene chloride, vinyl acetate, vinyl propionate 3-mer (meth) acryloyloxypropyltrimethoxysilane, 2- (meth) acryloyloxyethyltrimethoxysilane, 3- (meth) acryloyloxypropyltriethoxysilane, 2- (meth) acryloyloxyethyltriethoxysilane Alkoxysilyl group-containing vinyl monomers such as 3-, (meth) acryloyloxypropylmethyldimethoxysilane, styryltrimethoxysilane, styryltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane Divinylbenzene, diallylbenzene, ethylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate , Triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, allyl (meth) acrylate, N, N′-methylenebis ( And polyfunctional monomers such as (meth) acrylamide and triallyl cyanurate. These may be used alone or in combination of two or more. Among these, methyl methacrylate and styrene are particularly preferable as components for improving the hardness and initial gloss of the coating film. In addition, ethyl acrylate, n-butyl acrylate, and n-butyl methacrylate are particularly preferable as components that improve the appearance, flexibility, and adhesion to the substrate.
“(Meth) acrylate” means “acrylate and / or methacrylate”, “(meth) acrylonitrile” means “acrylonitrile and / or methacrylonitrile”, and “(meth) acrylamide” means “acrylamide and / or methacrylamide”. "(Meth) acryloyl" means "acryloyl and / or methacryloyl", respectively.

  The content of the monomer (c) is preferably 10 to 97.5% by mass and more preferably 30 to 96% by mass in 100% by mass of the vinyl polymer (A). When the content is 10% by mass or more, the appearance and initial gloss of the coating film tend to be improved. On the other hand, if the content is 97.5% by mass or less, the hardness, water resistance and solvent resistance of the coating film tend to be improved.

  The method for producing such a vinyl polymer (A) containing each monomer unit is not particularly limited, and known methods such as suspension polymerization, bulk polymerization, solution polymerization, and emulsion polymerization are known. These polymerization methods can be mentioned. Among these, the suspension polymerization method is preferable. When the vinyl polymer (A) is produced by a suspension polymerization method, water can be used as a medium, and the oil droplet viscosity can be increased because it does not contain a solvent. Furthermore, since the monomer concentration in the polymerization reaction field can be set high, polymerization at a relatively low temperature and in a short time becomes possible, and the carboxyl group of the monomer (a) and the epoxy of the monomer (b) during the polymerization It tends to suppress the progress of the reaction with the group. Even if the reaction between the carboxyl group and the epoxy group proceeds during the polymerization, the polymer becomes a crosslinked particle and does not lead to gelation of the entire system. It is preferable to polymerize by a polymerization method.

The method for producing the vinyl polymer (A) by suspension polymerization is not particularly limited. For example, a mixture of monomers constituting the vinyl polymer (A) in an aqueous medium (monomer mixture). (A)), a dispersing agent, a polymerization initiator, a chain transfer agent, etc. are added, and this is stirred and suspended to form a suspension, and then the suspension is heated to proceed polymerization. Is mentioned. Furthermore, the vinyl polymer (A) is obtained by filtering, washing, dehydrating and drying the suspension after polymerization.
In addition, when the glass transition temperature (Tg) of the obtained vinyl polymer (A) is low and handling as a powder is difficult, a basic compound (described later) is added to the suspension after suspension polymerization. The water-soluble resin solution (I) can be directly produced by adding B).

  The polymerization temperature for producing the vinyl polymer (A) is not particularly limited, but is preferably 30 to 130 ° C, more preferably 50 to 100 ° C. When the polymerization temperature is 30 ° C. or higher, the polymerization proceeds in a relatively short time, and the productivity of the vinyl polymer (A) tends to be improved. On the other hand, if the polymerization temperature is 130 ° C. or lower, the reaction between the carboxyl group of the monomer (a) and the epoxy group of the monomer (b) tends to be suppressed.

  Although it does not restrict | limit especially as a dispersing agent, For example, the alkali metal salt of poly (meth) acrylic acid, the copolymer of the alkali metal salt of (meth) acrylic acid and (meth) acrylic acid ester, (meth) acrylic acid sulfone Alkali alkali metal salt and (meth) acrylic acid ester copolymer, polystyrene sulfonic acid alkali metal salt, styrene sulfonic acid alkali metal salt and (meth) acrylic acid ester copolymer, or these monomers Copolymers composed of combinations; polyvinyl alcohol having a saponification degree of 70 to 100%, methyl cellulose and the like. These may be used alone or in combination of two or more. Among these, a copolymer of an alkali metal salt of (alkyl) sulfoalkyl (meth) acrylate and a (meth) acrylic acid ester having good dispersion stability during suspension polymerization is preferable.

Although the compounding quantity of a dispersing agent is not restrict | limited in particular, 0.005-5 mass parts is preferable with respect to 100 mass parts of monomer mixtures (A), and 0.01-1 mass part is more preferable. If the amount of the dispersant is 0.005 parts by mass or more, the dispersion stability during suspension polymerization tends to be improved. On the other hand, when the blending amount of the dispersant is 5 parts by mass or less, the detergency after polymerization, dewaterability, drying property, and water resistance of the coating film tend to be improved.
In addition, you may use together an inorganic electrolyte in order to improve the dispersion stability at the time of suspension polymerization. Although it does not restrict | limit especially as an inorganic electrolyte, For example, sodium carbonate, potassium carbonate, sodium hydrogencarbonate, sodium sulfate, manganese sulfate etc. are mentioned. These may be used alone or in combination of two or more.

  The polymerization initiator is not particularly limited. For example, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2-methylbutyronitrile), 2,2′-azobis (2,4 -Dimethylvaleronitrile), azo compounds such as dimethyl 2,2'-azobisisobutyrate; lauroyl peroxide, stearoyl peroxide, benzoyl peroxide, bis (4-t-butylcyclohexyl) peroxydicarbonate, 1, 1,3,3-tetramethylbutylperoxy 2-ethylhexanoate, t-hexylperoxy 2-ethylhexanoate, t-butylperoxy 2-ethylhexanoate, t-hexylperoxyisopropyl monocarbonate , T-butyl peroxyisopropyl monocarbonate, diisopropyl Organic peroxides such as hydrogen peroxide, cumene hydroperoxide, t-butyl hydroperoxide, t-hexyl hydroperoxide; inorganic peroxides such as hydrogen peroxide, potassium persulfate, sodium persulfate, ammonium persulfate Etc. These may be used alone or in combination of two or more. Among these, lauroyl peroxide is preferable.

  Although the compounding quantity of a polymerization initiator is not restrict | limited in particular, 0.05-10 are preferable with respect to 100 mass parts of monomer mixtures (A), and 0.1-5 mass parts is more preferable. If the blending amount of the polymerization initiator is 0.05 parts by mass or more, the polymerization proceeds in a relatively short time, and the productivity of the vinyl polymer (A) tends to be improved. On the other hand, when the blending amount of the polymerization initiator is 10 parts by mass or less, the heat generated by polymerization tends to be relaxed, and the polymerization temperature tends to be easily controlled.

  The chain transfer agent is blended for the purpose of adjusting the molecular weight of the vinyl polymer (A). The chain transfer agent is not particularly limited, but examples thereof include alkyl mercaptans such as n-butyl mercaptan, sec-butyl mercaptan, n-octyl mercaptan, n-dodecyl mercaptan, n-octadecyl mercaptan; 2-ethylhexyl thioglycolate, Thioglycolic acid esters such as methoxybutyl thioglycolate, trimethylolpropane tris (thioglycolate); 2-ethylhexyl β-mercaptopropionate, 3-methoxybutyl β-mercaptopropionate, trimethylolpropane tris (β-thiol) And mercaptopropionic acid esters such as propionate). These may be used alone or in combination of two or more. Among these, n-octyl mercaptan, n-dodecyl mercaptan, and 2-ethylhexyl thioglycolate are particularly preferable in terms of improving the appearance and initial gloss of the coating film.

  Although the compounding quantity of a chain transfer agent is not restrict | limited in particular, 0.05-10 mass parts is preferable with respect to 100 mass parts of monomer mixtures (A), and 0.1-5 mass parts is more preferable. If the blending amount of the chain transfer agent is 0.05 parts by mass or more, the reaction between the carboxyl group of the monomer (a) and the epoxy group of the monomer (b) is suppressed, and the appearance and initial stage of the coating film are reduced. Gloss tends to improve. On the other hand, if the blending amount of the chain transfer agent is 10 parts by mass or less, the residual amount of unreacted monomer and chain transfer agent is decreased, and the hardness and solvent resistance of the coating film tend to be improved.

  The Tg of the vinyl polymer (A) thus obtained is preferably from 0 to 150 ° C, more preferably from 10 to 120 ° C, particularly preferably from 20 to 100 ° C. When the Tg of the vinyl polymer (A) is 0 ° C. or higher, the hardness, water resistance, and solvent resistance of the coating film tend to be improved. On the other hand, if the Tg of the vinyl polymer (A) is 150 ° C. or less, the adhesion, appearance, and initial gloss of the coating film tend to be improved.

In addition, Tg of the vinyl-type polymer (A) in this invention and the polymer (C) mentioned later is the value computed from following formula (1).
1 / Tg = Σ (w _i / Tg _i ) (1)
In the formula (1), w _i represents the weight fraction of the monomer i which constitutes the polymer, Tg _i represents the glass transition temperature of the homopolymer of the monomer i, Tg and in the formula (1) tg _i is a value expressed in absolute temperature (K). Further, Tg _i is a value in the "POLYMER HANDBOOK, FOURTH EDITION, VI / 193~VI / 253 ".

  Moreover, especially the mass average molecular weight of a vinyl type polymer (A) is although it does not restrict | limit, 5,000-200,000 are preferable and 10,000-100,000 are more preferable. If the weight average molecular weight of the vinyl polymer (A) is 5,000 or more, the water resistance and solvent resistance of the coating film tend to be improved. On the other hand, if the weight average molecular weight of the vinyl polymer (A) is 200,000 or less, the water solubility of the vinyl polymer (A) is improved by the addition of the basic compound (B) to be described later. The appearance and initial gloss of the film tend to be improved.

Further, the mass average molecular weight / number average molecular weight (Mw / Mn) of the vinyl polymer (A) is not particularly limited, but is preferably 4 or less, more preferably 3 or less. If Mw / Mn of the vinyl polymer (A) is 4 or less, the appearance and initial gloss of the coating film tend to be improved.
Furthermore, the acid value of the vinyl polymer (A) is not particularly limited, but is preferably 15 to 250 mgKOH / g, and more preferably 20 to 200 mgKOH / g. If the acid value of the vinyl polymer (A) is 15 mgKOH / g or more, the addition of the basic compound (B) described later improves the water solubility of the vinyl polymer (A) and improves the coating film. Adhesion, hardness, and solvent resistance tend to improve. On the other hand, when the acid value of the vinyl polymer (A) is 250 mgKOH / g or less, the viscosity tends to be lowered or it is likely to be highly solid differentiated when the water-soluble resin solution (I) is obtained.

<Basic compound (B)>
The basic compound (B) neutralizes the vinyl polymer (A) described above.
The basic compound (B) is not particularly limited, and examples thereof include ammonia, triethylamine, propylamine, dibutylamine, amylamine, 1-aminooctane, 2-dimethylaminoethanol, ethylaminoethanol, 2-diethylaminoethanol, 1- Amino-2-propanol, 2-amino-1-propanol, 3-amino-1-propanol, 1-dimethylamino-2-propanol, 3-dimethylamino-1-propanol, 2-propylaminoethanol, ethoxypropylamine, Examples include aminobenzyl alcohol, morpholine, sodium hydroxide, potassium hydroxide, sodium carbonate and the like. These may be used alone or in combination of two or more. Among these, ammonia and amine compounds that tend to improve the appearance, initial gloss, and water resistance of the coating film are preferable.

  Although the usage-amount of a basic compound (B) is not restrict | limited in particular, 0.5-1.5 molar equivalent is preferable with respect to the carboxyl group of a vinyl type polymer (A), 0.8-1.2 mol The equivalent is more preferable. If the usage-amount of a basic compound (B) is 0.5 molar equivalent or more, it exists in the tendency for the water solubility of a vinyl type polymer (A) to improve, and for the external appearance and initial stage glossiness of a coating film to improve. On the other hand, if the usage-amount of a basic compound (B) is 1.5 molar equivalent or less, it exists in the tendency for the water resistance of a coating film to improve.

<Method for producing water-soluble resin solution (I)>
The water-soluble resin solution (I) used in the present invention is obtained by neutralizing the above-described vinyl polymer (A) with the basic compound (B). It is produced by mixing the union (A) and the basic compound (B).
The mixing method of the vinyl polymer (A) and the basic compound (B) is not particularly limited. For example, after the vinyl polymer (A) is dispersed in a solvent (S) containing water, Examples thereof include a method of adding the basic compound (B) and a method of adding the vinyl polymer (A) to the solvent (S) containing the basic compound (B) and water.
In the present invention, “neutralize” means that a part or all of the carboxyl groups in the vinyl polymer (A) are neutralized with the basic compound (B) to form carboxylates. It points to. That is, the usage-amount of a basic compound (B) does not necessarily need to be an equivalent with respect to the carboxyl group of a vinyl type polymer (A), and should just be in the range mentioned above.

The solvent (S) is a solvent containing water, and includes water and, if necessary, a hydrophilic organic solvent.
Although it does not restrict | limit especially as a hydrophilic organic solvent, For example, alcohol, such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, t-butanol; Ethylene glycol, ethylene glycol monomethyl ether, ethylene glycol mono Ethylene glycol derivatives such as acetate, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoacetate, triethylene glycol, triethylene glycol monomethyl ether; propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monobutyl ether propionate, 1 -Butoxyethoxypropanol, dipro Ethers such as tetrahydrofuran; glycol, dipropylene glycol monomethyl ether, propylene glycol derivatives such as tripropylene glycol monomethyl ether, acetone, and the like ketones such as methyl ethyl ketone. These may be used alone or in combination of two or more.

The mass ratio of water to the hydrophilic organic solvent (water / hydrophilic organic solvent) in the solvent (S) is not particularly limited, but water / hydrophilic organic solvent = 70/30 to 99.5 / 0.5 is preferable. 80/20 to 99/1 are more preferable, and 90/10 to 98/2 are particularly preferable. However, the total of water and the hydrophilic organic solvent is 100% by mass.
If the mass ratio of water / hydrophilic organic solvent is 70/30 or more, the solvent odor due to the hydrophilic organic solvent tends to be reduced or ignition is likely to be suppressed. On the other hand, when the mass ratio of water / hydrophilic organic solvent is 99.5 / 0.5 or less, the viscosity increases when the vinyl polymer (A) is water-solubilized by the addition of the basic compound (B). It tends to relax.

  Although the usage-amount of a solvent (S) is not restrict | limited in particular, 100-2000 mass parts is preferable with respect to 100 mass parts of vinyl polymer (A), 150-900 mass parts is more preferable, 200-600 mass parts Is particularly preferred. If the usage-amount of a solvent (S) is 100 mass parts or more, it exists in the tendency for the handleability at the time of setting it as a composition, a coating property, etc. to improve. On the other hand, if the usage-amount of a solvent (S) is 2000 mass parts or less, it exists in the tendency for the drying property at the time of coating-film formation to improve.

The water-soluble resin solution (I) thus obtained does not need to be completely dissolved in the solvent (S) described above, and a part thereof may exist in a dispersed state.
The form of the water-soluble resin solution (I) is not particularly limited, and examples thereof include a transparent aqueous solution, a translucent colloidal dispersion, and a milky white emulsion. Especially, the aqueous solution which accelerates | stimulates the film forming property of the water-insoluble resin dispersion liquid (II) mentioned later, and tends to improve the external appearance of a coating film, initial gloss, and water resistance is preferable.

  Moreover, especially the viscosity of water-soluble resin solution (I) is although it does not restrict | limit, 10-1000 mPa * s is preferable and 20-500 mPa * s is more preferable. When the viscosity of the water-soluble resin solution (I) is 10 mPa · s or more, the storage stability and paintability of the resulting composition tend to be improved. On the other hand, if the viscosity of the water-soluble resin solution (I) is 1000 mPa · s or less, the productivity and the handleability tend to be improved.

[Water-insoluble resin dispersion (II)]
The water-insoluble resin dispersion (II) used in the present invention is a dispersion in which a polymer (C) shown below is dispersed in an aqueous medium using an emulsifier.
Although it does not restrict | limit especially as a polymer (C), For example, acrylic resin, alkyd resin, urethane resin, epoxy resin, diallyl phthalate resin, cellulose resin, vinyl resin, phenol resin, polyolefin resin, polyester resin, melamine resin, urea Resin etc. are mentioned. These may be used alone or in combination of two or more. Among these, acrylic resins and vinyl resins that tend to improve the appearance and initial gloss of the coating film are preferable.

  Although it does not restrict | limit especially as a monomer unit which comprises a polymer (C), For example, when a polymer (C) is an acrylic resin and / or a vinyl resin, it comprises the said vinyl-type polymer (A). Examples of the monomer unit include vinyl monomer units (a), (b), and (c). As each monomer unit, one or more types selected from the vinyl monomer units (a), (b), and (c) exemplified above may be used.

Moreover, especially the mass average molecular weight of a polymer (C) is although it does not restrict | limit, 10,000-2,000,000 are preferable and 50,000-1,000,000 are more preferable. When the mass average molecular weight of the polymer (C) is 10,000 or more, the water resistance and solvent resistance of the coating film tend to be improved. On the other hand, if the mass average molecular weight of the polymer (C) is 2,000,000 or less, the appearance and initial gloss of the coating film tend to be improved.
Furthermore, Tg of a polymer (C) is not specifically limited, However, -20-100 degreeC is preferable and 0-80 degreeC is more preferable. If the Tg of the polymer (C) is −20 ° C. or higher, the hardness, water resistance and solvent resistance of the coating film tend to be improved. On the other hand, when the Tg of the polymer (C) is 100 ° C. or lower, the film forming property, adhesion, appearance, and initial gloss of the coating film tend to be improved.

<Method for producing water-insoluble resin dispersion (II)>
The method for producing the water-insoluble resin dispersion (II) is not particularly limited. For example, a known polymerization method such as an emulsion polymerization method, or a surfactant such as an emulsifier obtained from a resin solution obtained by dissolving a resin in an organic solvent. And a method of dispersing in an aqueous medium containing a high shear force. Among these, an emulsion polymerization method using a small amount of organic solvent is preferable.

The method for producing the water-insoluble resin dispersion (II) by the emulsion polymerization method is not particularly limited. For example, each raw material (mixture of monomers constituting the polymer (C) (single amount) in an aqueous medium is used. Body mixture (C)), an emulsifier, a polymerization initiator, a chain transfer agent, etc.), and emulsifying this to obtain an emulsion, followed by heating and polymerizing the emulsion. A water-insoluble resin dispersion (II) in which the polymer (C) is dispersed in an aqueous medium is obtained.
The method for adding (preparing) each of the above raw materials is not particularly limited. For example, a method of batch charging into the reaction system, a method of charging a part and then charging the remainder continuously or divided, the total amount For example, a method of continuously charging is used. In particular, when a part is charged and then the remainder is continuously or dividedly charged, the resulting polymer (C) has a core-shell structure and is more excellent in film forming properties.

  The polymerization temperature for producing the water-insoluble resin dispersion (II) by the emulsion polymerization method is not particularly limited, but is preferably 30 to 130 ° C, more preferably 50 to 100 ° C. When the polymerization temperature is 30 ° C. or higher, the polymerization proceeds in a relatively short time and the productivity of the water-insoluble resin dispersion (II) tends to be improved. On the other hand, when the polymerization temperature is 130 ° C. or lower, the dispersion stability during emulsion polymerization tends to be improved.

  Although it does not restrict | limit especially as an emulsifier, For example, Nonionic emulsifiers, such as polyoxyethylene nonyl phenyl ether and polyoxyethylene octyl phenyl ether; Higher alcohol sulfuric acid ester sodium salt, alkylbenzenesulfonic acid sodium salt, succinic acid dialkylester sodium sulfonate Salts, anionic emulsifiers such as sodium alkyldiphenyl ether disulfonate; cationic emulsifiers such as alkylpyridinyl chloride and alkylammonium chloride; sodium styrenesulfonate, sodium allylalkylsulfonate, alkylallylsulfosuccinate, polyoxyethylene alkylallyl Glycerin ether sulfate, polyoxyethylene alkylphenol allyl glycerin ether sulfate Such reactive emulsifying agents. These may be used alone or in combination of two or more. Moreover, you may use a commercially available thing.

  Although the compounding quantity of an emulsifier is not restrict | limited in particular, 0.005-5 mass parts is preferable with respect to 100 mass parts of monomer mixtures (C), and 0.01-3 mass parts is more preferable. If the amount of the emulsifier is 0.005 parts by mass or more, the dispersion stability during emulsification tends to be improved. On the other hand, if the amount of the emulsifier is 5 parts by mass or less, the water resistance of the coating film tends to be improved.

Although it does not restrict | limit especially as a polymerization initiator, For example, you may select and use suitably 1 or more types from the polymerization initiator illustrated previously in description of the said vinyl-type polymer (A).
Although the compounding quantity of a polymerization initiator is not restrict | limited in particular, 0.05-10 mass parts is preferable with respect to 100 mass parts of monomer mixtures (C), and 0.1-5 mass parts is more preferable. If the amount of the polymerization initiator is 0.05 parts by mass or more, the polymerization proceeds in a relatively short time, and the productivity of the water-insoluble resin dispersion (II) tends to be improved. On the other hand, when the blending amount of the polymerization initiator is 10 parts by mass or less, the heat generated by polymerization tends to be relaxed, and the polymerization temperature tends to be easily controlled.

  In addition, when using a peroxide-type initiator as a polymerization initiator, you may use a reducing agent together for the purpose of acceleration | stimulation of superposition | polymerization. Although it does not restrict | limit especially as a reducing agent, For example, sodium disulfite, sodium hydrogensulfite, sodium thiosulfate, ferrous sulfate, L-ascorbic acid and its salt, Rongalite etc. are mentioned.

A chain transfer agent is mix | blended in order to adjust the molecular weight of a polymer (C). Although it does not restrict | limit especially as a chain transfer agent, For example, you may select and use suitably 1 or more types from the chain transfer agent illustrated previously in description of the said vinyl-type polymer (A).
Although the compounding quantity of a chain transfer agent is not restrict | limited in particular, 0.05-10 mass parts is preferable with respect to 100 mass parts of monomer mixtures (C), and 0.1-5 mass parts is more preferable. When the amount of the chain transfer agent is 0.05 parts by mass or more, the appearance and initial gloss of the coating film tend to be improved. On the other hand, if the blending amount of the chain transfer agent is 10 parts by mass or less, the residual amount of unreacted monomer and chain transfer agent is decreased, and the hardness and solvent resistance of the coating film tend to be improved.

[Composition]
The composition of the present invention can be obtained by mixing the water-soluble resin solution (I) and the water-insoluble resin dispersion (II).
The mixing method is not particularly limited. For example, the method of adding the water-soluble resin solution (I) to the water-insoluble resin dispersion (II), or the water-insoluble resin dispersion in the presence of the water-soluble resin solution (I). A method for producing the liquid (II), a method for adding the basic compound (B) after dispersing the vinyl polymer (A) in the water-insoluble resin dispersion (II), and containing the basic compound (B) And a method of adding the vinyl polymer (A) to the water-insoluble resin dispersion (II).
The composition of the present invention contains a vinyl polymer (A) containing a carboxyl group-containing vinyl polymer unit (a) and an epoxy group-containing vinyl polymer unit (b). Reacts and cures. Therefore, it is preferable to mix the water-soluble resin solution (I) and the water-insoluble resin dispersion (II) at room temperature.

When mixing the water-soluble resin solution (I) and the water-insoluble resin dispersion (II), the mass ratio (in terms of solid content) of the water-soluble resin solution (I) and the water-insoluble resin dispersion (II) is The water-soluble resin solution (I) / the water-insoluble resin dispersion (II) is preferably mixed so as to be 1/99 to 50/50, more preferably 2/98 to 30/70. Preferably it is 3 / 97-10 / 90. If the mass ratio of the water-soluble resin solution (I) and the water-insoluble resin dispersion (II) is 1/99 or more, the adhesion, hardness, water resistance, and solvent resistance of the coating film tend to be improved. On the other hand, when the mass ratio of the water-soluble resin solution (I) to the water-insoluble resin dispersion (II) is 50/50 or less, the appearance and initial gloss of the coating film tend to be improved.
The mass ratio between the water-soluble resin solution (I) and the water-insoluble resin dispersion (II) is substantially the mass ratio between the vinyl polymer (A) and the polymer (C).

  The composition of this invention may mix | blend a curing catalyst as needed. The curing catalyst is not particularly limited, but examples thereof include tetramethylammonium bromide, tetraethylammonium hydroxide, tetra n-butylammonium chloride, tetra n-butylammonium bromide, tetra n-butylammonium phosphate, tetra n-dodecylammonium chloride, Quaternary ammonium salts such as trimethylbenzylammonium hydroxide and phenyltrimethylammonium bromide; allyltriphenylphosphonium chloride, n-amyltriphenylphosphonium bromide, benzyltriphenylphosphonium chloride, bromomethyltriphenylphosphonium Bromide, ethoxycarbonylphosphonium bromide, n-heptyltriphenylphosphonium bromide, methyltriphe Le phosphonium bromide, etc. phosphonium salts such as tetraphenyl phosphonium bromide. These may be used alone or in combination of two or more.

  The blending amount of the curing catalyst is not particularly limited, but is 0.001 to 0.000 based on 100 parts by mass in total of the solid content of the water-soluble resin solution (I) and the solid content of the water-insoluble resin dispersion (II). 5 mass parts is preferable and 0.005-0.1 mass part is more preferable. If the compounding quantity of a curing catalyst is 0.001 mass part or more, the reactivity of the carboxyl group of a vinyl polymer (A) and an epoxy group will improve, and it exists in the tendency for water resistance and solvent resistance to improve. On the other hand, when the blending amount of the curing catalyst is 0.5 parts by mass or less, coloring and coating film defects due to the curing catalyst tend to decrease.

  Further, the composition of the present invention may include a colorant, a filler, a pigment dispersant, an antigelling agent, an antioxidant, a radical scavenger, an ultraviolet absorber, a leveling agent, a repellency inhibitor, a dripping agent, if necessary. You may mix | blend various additives, such as a stopper, a slip agent, antiseptic | preservative, and a plasticizer.

According to the composition of the present invention thus obtained, a vinyl containing a carboxyl group-containing vinyl polymer unit (a) and an epoxy group-containing vinyl polymer unit (b) as the water-soluble resin solution (I). Since the polymer (A) is used, the amount of the hydrophilic organic solvent used can be suppressed. Therefore, the load on the environment can be reduced.
In addition, when the composition of the present invention is used as an aqueous binder such as a paint, ink, or adhesive, a coating film having high hardness and excellent water resistance and solvent resistance can be formed.

Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited thereto. In the following description, “part” represents “part by mass”.
Here, physical property measurement and evaluation methods are shown below.

(1) Measurement of glass transition temperature (Tg) Tg was calculated from the above formula (1).

(2) Measurement of mass average molecular weight A THF solution in which 0.4% by mass of vinyl polymer (A) was dissolved was prepared. 100 μL of the THF solution was collected and measured at 40 ° C. using gel permeation chromatography (GPC) (“HLC-8120” manufactured by Tosoh Corporation). As the column, a column obtained by connecting “TSKgel G5000HXL” and “GMHXL-L” manufactured by Tosoh Corporation in series was used. The calibration curve was prepared using F288 / F80 / F40 / F10 / F4 / F1 / A5000 / A1000 / A500 (manufactured by Tosoh Corporation, standard polystyrene) and a styrene monomer. From the calibration curve, Mw (mass average molecular weight), Mn (number average molecular weight), and Mw / Mn (mass average molecular weight / number average molecular weight) were calculated in terms of standard polystyrene.

(3) Measurement of Acid Value A vinyl polymer (A) having a solid content of about 1 g was precisely weighed, and 50 g of a solvent (isopropanol / acetone / water = 50/25/25 mass%) was added and dissolved. To this, 0.2N potassium hydroxide (KOH) -ethanol solution was titrated based on the discoloration point of phenolphthalein, and the number of mg of KOH (acid value) required to neutralize 1 g of solid content was determined. It computed from following formula (2).
Acid value (mgKOH / g) = A × 0.2 × f × 56.1 / Sample solid mass (g) (2)
Here, A is the titer (ml), and f is the titer of 0.2 N potassium hydroxide solution.

(4) Measurement of viscosity The viscosity of the water-soluble resin solution (I) maintained at 25 ° C. was measured using a B-type viscometer (manufactured by TOKIMEC, “R100-type viscometer (RB type)”).

(5) Evaluation of coating film appearance The coating film surface of the test plate was visually observed and judged according to the following criteria.
○: There is no abnormality in gloss unevenness, repellency, cracking and leveling.
X: Abnormal glossiness, repellency, cracking, and leveling.

(6) Evaluation of adhesion The adhesion between the Suken middle-coated dull steel sheet and the coating film was measured by a cross-cut method according to JIS K 5600-5-6: 1999.
In addition, the numerical value shown in Table 3 represents the area remaining without peeling in%, and the closer to 100%, the better the adhesion.

(7) Evaluation of coating film hardness The pencil hardness of the coating film was measured by a hand-drawing method according to JIS K 5600-5-4: 1999.
It should be noted that 2B or more is acceptable and 3B or less is unacceptable.

(8) Evaluation of initial gloss The specular gloss (G ₀ ) of the coating film at incident angles of 60 ° and 20 ° was measured using a gloss meter (manufactured by Nippon Denshoku Industries Co., Ltd., “VG-2000”).
The specular gloss at 60 ° was 80.0 or more as acceptable and less than 80.0 as unacceptable. Moreover, the specular glossiness of 20 ° was determined to be 70.0 or more, and less than 70.0 was rejected.

(9) Evaluation of water resistance Gloss retention measurement;
As a water resistance test of the coating film, the test plate was immersed in deionized water and kept in a constant temperature water bath at 50 ° C. for 8 weeks. Thereafter, in the same manner as the evaluation of the initial gloss of (8) above, the specular gloss (G ₁ ) of the coating film at incident angles of 60 ° and 20 ° was measured, and the gloss retention was calculated from the following formula (3). .
In addition, the gloss retention of the 60 ° specular gloss was 95.0% or more as acceptable and less than 95.0% as unacceptable. Further, the gloss retention of the 20 ° specular gloss was 75.0% or more as acceptable and less than 75.0% as unacceptable.
Gloss retention (%) = (G ₁ / G ₀ ) × 100 (3)

Measurement of color difference;
The number of colors of the coating film was measured using a spectroscopic color difference meter (manufactured by Nippon Denshoku Industries Co., Ltd., “SE-2000”). The initial number of colors (L ₀ , a ₀ , b ₀ ) and the number of colors after the water resistance test (L ₁ , a ₁ , b ₁ ) were measured, and the color difference (ΔE) was calculated from the following formula (4).
In addition, (triangle | delta) E made 0.8 or less pass, and made the case where it exceeded 0.8 disqualified.
Color difference (ΔE) = {(L ₁ −L ₀ ) ² + (a ₁ −a ₀ ) ² + (b ₁ −b ₀ ) ² } ^1/2 (4)

(10) Evaluation of solvent resistance The test plate was immersed in xylene at 25 ° C. for 1 minute, the state of the coating film was visually observed, and judged according to the following criteria.
○: No abnormality.
Δ: Gloss slightly decreased.
X: The coating film was whitened or dissolved.

[Production of Dispersant 1]
In a polymerization apparatus equipped with a stirrer, a condenser, and a thermometer, 900 parts of deionized water, 60 parts of sodium 2-sulfoethyl methacrylate, 10 parts of potassium methacrylate, and 12 parts of methyl methacrylate were added and stirred, and the polymerization apparatus While replacing the inside with nitrogen, the temperature was raised to 50 ° C. (polymerization temperature), and 0.08 part of 2,2′-azobis (2-methylpropionamidine) dihydrochloride was added as a polymerization initiator, and the temperature was raised to 60 ° C. Warm up. Simultaneously with the addition of the polymerization initiator, methyl methacrylate was continuously added dropwise at a rate of 0.24 parts / minute for 75 minutes using a dropping pump. After holding at 60 ° C. for 6 hours, the mixture was cooled to room temperature to obtain Dispersant 1 which was a transparent polymer aqueous solution. The dispersant 1 had a solid content of 10% and a viscosity of 950 mPa · s.

[Production of vinyl polymer (A-1)]
In a polymerization apparatus equipped with a stirrer, a condenser, and a thermometer, 170 parts of deionized water, 0.1 part of sodium sulfate, and 0.2 part of dispersant 1 (solid content 10%) are added and stirred. An aqueous solution was obtained. Next, a mixture of monomers having the composition shown in Table 1 (8 parts of methacrylic acid as monomer (a), 1.65 parts of glycidyl methacrylate as monomer (b), and methyl as monomer (c) Methacrylate, 52.35 parts, n-butyl methacrylate 28 parts, n-butyl acrylate 10 parts), lauroyl peroxide 1.5 parts as a polymerization initiator, and 1.9 parts n-dodecyl mercaptan as a chain transfer agent. A suspension was obtained. Next, the inside of the polymerization apparatus was purged with nitrogen, heated to 70 ° C. and reacted for about 1 hour, further heated to 90 ° C. and held for 0.5 hour, then cooled to 40 ° C. An aqueous suspension containing the polymer (A-1) was obtained. This aqueous suspension is filtered through a nylon filter cloth having an opening of 45 μm, and the filtrate is washed with deionized water, dehydrated, and dried at 40 ° C. for 16 hours to obtain a vinyl polymer (A-1). Obtained. Tg of this vinyl polymer (A-1) was 60 ° C., Mw was 25,600, Mw / Mn was 2.12, and the acid value was 51.6 mgKOH / g. The results are shown in Table 1.

[Production of water-soluble resin solution (I-1)]
In a device equipped with a stirrer, a condenser, and a thermometer, 100 parts of vinyl polymer (A-1) and 273.7 parts of deionized water are added and stirred at room temperature, and then 15 parts of isopropanol (IPA). And 11.3 parts of 14 mass% ammonia water was added as a basic compound (B), and stirring was continued for 1 hour, and the water-soluble resin solution (I-1) was obtained. This water-soluble resin solution (I-1) was transparent, the solid content was 25 mass%, and the viscosity was 114 mPa · s. The results are shown in Table 2.
The transparency of the water-soluble resin solution (I-1) was determined visually.

[Production of vinyl polymers (A-2) to (A-4) and (A-7)]
A vinyl polymer (A-) is the same as the vinyl polymer (A-1) except that the amount (parts) of the monomer, chain transfer agent and polymerization initiator is changed as shown in Table 1. 2) to (A-4) and (A-7) were produced. Table 1 shows the characteristics of the vinyl polymers (A-2) to (A-4) and (A-7).

[Production of water-soluble resin solutions (I-2) to (I-4) and (I-7)]
A water-soluble resin solution (I-) was prepared in the same manner as the water-soluble resin solution (I-1) except that the vinyl polymer (A) shown in Table 2 was used and the solid content shown in Table 2 was adjusted. 2) to (I-4) and (I-7) were produced. Table 2 shows the characteristics of the water-soluble resin solutions (I-2) to (I-4) and (I-7).

[Production of vinyl polymer (A-5), (A-6), water-soluble resin solution (I-5), (I-6)]
The same as the vinyl polymer (A-1) except that the amount of deionized water was 250 parts and the blending amount (parts) of monomer, chain transfer agent and polymerization initiator was changed as shown in Table 1. Thus, an aqueous suspension containing each of the vinyl polymers (A-5) and (A-6) was prepared. The properties of the vinyl polymers (A-5) and (A-6) are shown in Table 1. However, when measuring the characteristics, the same operations as for the vinyl polymer (A-1) were performed to produce the dried vinyl polymers (A-5) and (A-6). Each characteristic was measured.
Next, 75.5 parts of deionized water was added to each aqueous suspension containing the obtained vinyl polymers (A-5) and (A-6), and the mixture was stirred at room temperature. 17.7 parts and 11.3 parts of 14% by mass ammonia water as the basic compound (B) were added and stirring was continued for 1 hour to obtain water-soluble resin solutions (I-5) and (I-6). Obtained. Table 2 shows the characteristics of the water-soluble resin solutions (I-5) and (I-6).

Abbreviations in the table are as follows.
MAA: methacrylic acid,
GMA: glycidyl methacrylate,
MMA: methyl methacrylate,
BMA: n-butyl methacrylate,
BA: n-butyl acrylate,
LPO: Lauroyl peroxide
n-DM: n-dodecyl mercaptan.

[Production of water-insoluble resin dispersion (II-1)]
In a polymerization apparatus equipped with a stirrer, a cooling pipe, a thermometer, a dropping pump, and a nitrogen introduction pipe, 50 parts of deionized water, 2 parts of emulsifier (manufactured by ADEKA, "SR-1025"), 2 parts of methyl methacrylate After adding 6 parts of n-butyl methacrylate and 2 parts of t-butyl methacrylate and stirring, the inside of the polymerization apparatus was purged with nitrogen. Next, it heated up to 80 degreeC, 0.05 part of sodium persulfate was added, and it was made to react for 15 minutes. Next, emulsion 1 consisting of 18 parts of deionized water, 2 parts of emulsifier, 6 parts of methyl methacrylate, 18 parts of n-butyl methacrylate, 6 parts of t-butyl methacrylate and 0.05 part of sodium persulfate is added dropwise over 45 minutes. Added for 1 hour. Next, emulsion 2 comprising 36 parts of deionized water, 4 parts of emulsifier, 14 parts of methyl methacrylate, 40 parts of 2-ethylhexyl acrylate, 4 parts of 2-hydroxyethyl methacrylate, 2 parts of methacrylic acid, and 0.1 part of sodium persulfate Was added dropwise over 1.5 hours and held for 30 minutes, then 18.2 parts of deionized water was added and cooled to room temperature to disperse the water-insoluble resin containing the vinyl polymer (C-1). A liquid (II-1) was obtained. The water-insoluble resin dispersion (II-1) had a solid content of 45% by mass, an average particle size of 120 nm, and a viscosity of 600 mPa · s.
This water-insoluble resin dispersion (II-1) has a Tg of 49 ° C. core and a Tg of −20 ° C. shell, and the core / shell mass ratio (core / shell) is 40/60. It was a structural emulsion and had excellent film forming properties.

[Example 1]
20 parts of water-soluble resin solution (I-1) (5 parts in terms of resin solid content), 211.1 parts of water-insoluble resin dispersion (II-1) (95 parts in terms of resin solid content), tetra-n- as a curing catalyst 0.025 part of butylammonium bromide (TBAB) was mixed to obtain a composition.
The obtained composition was used as a paint, and it was applied to a Suken middle-coated dull steel plate (manufactured by Nippon Route Service Co., Ltd., standard test plate). 14 and held at room temperature for 0.5 hour, followed by heating and drying at 90 ° C. for 10 minutes to produce a test plate. The coating film of this test plate was evaluated by the above test.
The obtained results are shown in Table 3.

[Examples 2 to 6, Comparative Example 2]
Except having changed water-soluble resin solution (I) as shown in Table 3, it manufactured the composition and produced the test board like Example 1, and evaluated the coating film. The results are shown in Table 3.

[Comparative Example 1]
Without using a water-soluble resin solution, 222.2 parts of water-insoluble resin dispersion (II-1) (100 parts in terms of resin solid content) and 0.025 part of tetra n-butylammonium bromide (TBAB) as a curing catalyst Except for mixing, the composition was produced and the test plate was produced in the same manner as in Example 1, and the coating film was evaluated. The results are shown in Table 3.

As is apparent from the results shown in Table 3, in Examples 1 to 5, the appearance, adhesion, hardness, initial gloss, water resistance, and solvent resistance of the coating film were good. In Example 6, the glass transition temperature of the vinyl polymer (A-6) was -17 ° C., which was lower than that of the other vinyl polymers (A). Although it was inferior, the performance of other coating films was good.
On the other hand, in the comparative example 1 which does not contain water-soluble resin solution (I), the hardness of the coating film, water resistance, and solvent resistance were inferior compared with the Example.
In Comparative Example 2, the coating film hardness was improved as compared with Comparative Example 1 by containing the water-soluble resin solution (I-7). However, since the water-soluble resin solution (I-7) uses the vinyl polymer (A-7) not containing the epoxy group-containing vinyl monomer unit (b), the water resistance and solvent resistance can be improved. There wasn't. In particular, the solvent resistance was inferior to that of Comparative Example 1 that did not contain a water-soluble resin solution.

The composition of the present invention can be suitably used as an aqueous binder for paints, inks, adhesives and the like that have a low environmental load because the amount of the hydrophilic organic solvent used can be suppressed.
In addition, paints, inks, and adhesives using the composition of the present invention can form a coating film having high hardness and excellent water resistance and solvent resistance.
Furthermore, the composition of the present invention can be widely used in various fields such as resist materials and baking materials in addition to the applications of paints, inks, and adhesives, and is extremely useful industrially. is there.

Claims (3)

A composition comprising a water-soluble resin solution (I) obtained by neutralizing a vinyl polymer (A) with a basic compound (B), and a water-insoluble resin dispersion (II),
As a structural unit of the vinyl polymer (A), a carboxyl group-containing vinyl monomer unit (a) and an epoxy group-containing vinyl monomer unit (b) are included, and the carboxyl group-containing vinyl The molar equivalent ratio of the carboxy group of the monomer unit (a) and the epoxy group of the epoxy group-containing vinyl monomer unit (b) is carboxyl group / epoxy group = 1/30 to 30/1. The composition characterized by the above-mentioned. The composition according to claim 1, wherein the vinyl polymer (A) has a glass transition temperature (Tg) calculated using the following formula (1) of 0 to 150 ° C.
1 / Tg = Σ (w _i / Tg _i ) (1)
Wherein (1), w _i represents the weight fraction of the monomer i which constitutes the polymer, Tg _i represents the glass transition temperature of the homopolymer of the monomer i.   The composition according to claim 1 or 2, wherein the vinyl polymer (A) is produced by a suspension polymerization method.