JP5099402B2 - Water-based epoxy resin composition - Google Patents

Description

  The present invention relates to an aqueous epoxy resin composition that exhibits good water dispersibility and film-forming properties and can provide a coating film with excellent anticorrosion properties.

  In general, epoxy resin compositions have excellent mechanical and electrical properties, and cured products with good adhesion, solvent resistance, water resistance, heat resistance, etc. can be obtained. Widely used in chemicals, paints, civil engineering and other applications.

  Especially for paint applications, solvent dilution types using various organic solvents were common, but in recent years, volatile organic compounds (VOC) have been used from the viewpoint of global environmental conservation including air pollution prevention and work environment improvement. ) Progress toward the implementation of total volume regulation. For this reason, the water-based epoxy resin composition which does not use an organic solvent attracts attention. The aqueous epoxy resin composition is advantageous in terms of work environment, handling workability, and the like, and development of a curing agent used in the aqueous epoxy resin composition has been actively conducted.

  Conventionally, a modified polyamine obtained by adding an epoxy compound to a polyamine compound is known as a curing agent for an aqueous epoxy resin. However, such a modified polyamine can be dispersed in water when the addition rate of the epoxy compound is small. Although the solubility is relatively good, the resulting cured product has poor anticorrosion properties.On the other hand, increasing the addition rate has the problem that the anticorrosion properties are improved but the dispersibility and solubility in water are insufficient. ing.

  As a means for improving the above problem, for example, a curing agent for an aqueous epoxy resin obtained by modifying a polyamine compound having an oxypropylene chain with a specific polyglycidyl ether compound having an oxypropylene chain has been proposed (for example, Patent Document 1). reference.). However, the cured coating film obtained using the aqueous epoxy resin curing agent proposed in Patent Document 1 still has a water resistance that is not at a practical level, and further improvements are required.

JP-A-9-227658 (pages 3-6)

  Therefore, the present invention is an aqueous epoxy resin composition containing an epoxy resin (A) and an amine curing agent (B), compared with a conventional curing agent for an aqueous epoxy resin modified with a polyamine compound having an oxypropylene chain. Another object of the present invention is to provide an aqueous epoxy resin composition that exhibits good water dispersibility and film-forming properties and that can provide a coating film with excellent anticorrosion properties.

  As a result of intensive studies to solve the above problems, the present inventors have obtained an epoxy adduct compound obtained by reacting a bifunctional epoxy resin having a specific onium salt structure in the side chain with a polyamine compound as an amine curing agent. As a result, it was found that a cured coating film having excellent water dispersibility and film-forming property and good anticorrosion properties was obtained, and the present invention was completed.

That is, the present invention is an aqueous epoxy resin composition containing an epoxy resin (A) and an amine curing agent (B), and the amine curing agent (B) comprises a polyamine compound (b-1), It is a compound obtained by reacting a bifunctional epoxy group-containing resin (b-2) having a structure represented by the general formula (1) and having both molecular terminals as epoxy groups. An aqueous epoxy resin composition is provided. [In Formula (1), R ₁ , R ₂ , R ₃ , R ₄ , R ₅ are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ₆ , R ₇ , R ₈ , Each independently an alkyl group having 1 to 4 carbon atoms, R is a hydrogen atom or a methyl group, X is a single bond or an alkylene chain having 1 to 4 carbon atoms, Q is a nitrogen atom or a phosphorus atom, Y is a chlorine atom, a bromine atom, an iodine atom or a hydroxyl group. ]

  According to the present invention, it is possible to provide a curing agent for an aqueous epoxy resin that exhibits good water dispersibility when mixed with an epoxy resin, and the coating film obtained using the aqueous epoxy resin composition has anticorrosion properties, etc. Therefore, it can be suitably used for paints, adhesives, fiber sizing agents, concrete primers and the like.

Hereinafter, the present invention will be described in detail.
The epoxy resin (A) used in the present invention may be a compound having an epoxy group in the molecule, and the structure thereof is not particularly limited. For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, bisphenol S type epoxy resin, phenol novolac type epoxy resin, cresol novolak type epoxy resin, p-tert-butylphenol novolak type epoxy resin, nonylphenol novolak Type epoxy resins, polyvalent epoxy resins such as t-butylcatechol type epoxy resins, etc., and monovalent epoxy resins include aliphatic alcohols such as butanol, aliphatic alcohols having 11 to 12 carbon atoms, phenol, Monohydric phenols such as p-ethylphenol, o-cresol, m-cresol, p-cresol, p-tertiarybutylphenol, s-butylphenol, nonylphenol, xylenol and the like. A condensate with halohydrin, a condensate of monovalent carboxylic acid such as neodecanoic acid and epihalohydrin, and the like. Examples of glycidylamine include a condensate of diaminodiphenylmethane and epihalohydrin. And polyglycidyl ethers of vegetable oils such as soybean oil and castor oil, and polyvalent alkylene glycol type epoxy resins include ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, glycerin, erythritol , Polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, a condensate of trimethylolpropane and epihalohydrin, and further, an aqueous epoxy resin described in JP-A-2005-239928, and the like. These can be used in one kind, or may be used in combination of two or more.

  Even if the epoxy resin (A) is liquefied and reduced in viscosity by adding an organic solvent or a non-reactive diluent as necessary, a surfactant such as a polyoxyethylene alkylphenyl ether compound is used. An emulsified epoxy resin emulsified in advance may be used.

  Among these, it is preferable to use a bisphenol type epoxy resin or a t-butylcatechol type epoxy resin from the viewpoint of good curability of the aqueous epoxy resin composition and excellent corrosion resistance of the resulting cured coating film. It is preferable to use a bisphenol type epoxy resin.

  The amine-based curing agent (B) used in the present invention is obtained by further reacting the bifunctional epoxy group-containing resin (b-2) having a specific onium salt structure in the side chain with the polyamine compound (b-1). It is an epoxy adduct compound. By using such an amine-based curing agent (B), it is possible to combine the water dispersibility of the composition, which has been a problem with aqueous epoxy resin curing agents, and the corrosion resistance of the cured coating film. It is possible.

  The polyamine compound (b-1) is not particularly limited, and aliphatic polyamines, aromatic polyamines, heterocyclic polyamines, epoxy adducts thereof, Mannich modified products, polyamide modified products, and the like are used. Is possible. For example, methylenediamine, ethylenediamine, 1,2-diaminopropane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1 , 8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, etc., diethylenetriamine, dipropylenetriamine, triethylenetetramine, tripropylenetetramine, tetraethylenepentamine, tetrapropylenepentamine, pentaethylenehexamine, nonaethylene Decamine, trimethylhexamethylenediamine, etc., tetra (aminomethyl) methane, tetrakis (2-aminoethylaminomethyl) methane, 1,3-bis (2′-aminoethylamino) propane, triethylene-bis (trime Len) hexamine, bis (3-aminoethyl) amine, bishexamethylenetriamine, etc., 1,4-cyclohexanediamine, 4,4′-methylenebiscyclohexylamine, 4,4′-isopropylidenebiscyclohexylamine, norbornadiamine Bis (aminomethyl) cyclohexane, diaminodicyclohexylmethane, isophoronediamine, mensendiamine, etc., bis (aminoalkyl) benzene, bis (aminoalkyl) naphthalene, bis (cyanoethyl) diethylenetriamine, o-xylylenediamine, m-xylylenediamine Amine, p-xylylenediamine, phenylenediamine, naphthylenediamine, diaminodiphenylmethane, diaminodiethylphenylmethane, 2,2-bis (4-aminophenyl) propane, 4, '-Diaminodiphenyl ether, 4,4'-diaminobenzophenone, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfone, 2,2'-dimethyl-4,4'-diaminodiphenylmethane, 2,4'- Diaminobiphenyl, 2,3′-dimethyl-4,4′-diaminobiphenyl, 3,3′-dimethoxy-4,4′-diaminobiphenyl, bis (aminomethyl) naphthalene, bis (aminoethyl) naphthalene, etc., N- Methylpiperazine, morpholine, 1,4-bis- (8-aminopropyl) -piperazine, piperazine-1,4-diazacycloheptane, 1- (2′-aminoethylpiperazine), 1- [2 ′-(2 "-Aminoethylamino) ethyl] piperazine, 1,11-diazacycloeicosane, 1,15-di" Azacyclooctacosane and the like can be mentioned, and they can be used alone or as a mixture of two or more.

  Among these, aliphatic polyamines are preferable from the viewpoint of excellent curability, and metaxylylenediamine, isophoronediamine, and triethylenetetramine are preferably used from the viewpoint of excellent mechanical properties of the resulting cured product.

  The onium salt structure at the end of the side chain in the general formula (1) imparts hydrophilicity to the molecule, and the physical properties of the processed product (cured product) obtained by the aromatic skeleton in the main chain, particularly It is possible to prevent a decrease in mechanical properties.

  Although it does not restrict | limit especially as an epoxy equivalent of the said bifunctional epoxy resin (b-1), it is excellent in the corrosion resistance at the time of using for a coating use etc., and the adhesiveness to a base material, and is an aqueous | water-based epoxy resin composition. From the viewpoint of excellent storage stability, it is preferably 200 to 6000 g / eq, and particularly preferably 230 to 5000 g / eq.

Among the structures represented by the general formula (1), when synthesized by the production method described later, the availability of industrial raw materials, the storage stability when an aqueous epoxy resin composition is obtained, and the obtained processed product R ₁ , R ₂ , R ₃ , and R _{4 in the} general formula (1) are hydrogen atoms, and R ₅ , R ₆ , R ₇ , and R ₈ are methyl groups. Q is preferably a nitrogen atom, Y is preferably a chlorine atom or a hydroxyl group, X is preferably an ethylene chain, and R is preferably a hydrogen atom.

  As the bifunctional epoxy group-containing resin (b-2) having the structure represented by the general formula (1), the following general formula (3)

[In Formula (3), R < ₁ > -R < ₈ >, R, X, Q, and Y are the same as the above, p is an average value of the number of repetitions, and is 0-50. ]
Or a compound represented by the following general formula (4)

[In the formula (4), R _{1 to} R ₈ , R, X, Q, and Y are the same as described above, and A is different from the structure represented by the general formula (1). Of the compound having a hydroxyl group or a carboxyl group, q and r are average values of the number of repetitions, and q = 0 to 45 and r = 0 to 55, respectively. In addition, it shows that each repeating unit has couple | bonded at random. ]
The compound represented by these can be mentioned.

In the general formulas (3) and (4), R ₁ , R ₂ , R ₃ and R ₄ are hydrogen atoms, R ₅ , R ₆ , R ₇ and R ₈ are methyl groups, and Q is a nitrogen atom. The compound in which Y is a chlorine atom or a hydroxyl group is preferable from the viewpoint of excellent storage stability, corrosion resistance of the obtained workpiece, and the like, as described above.

  Furthermore, X in the general formulas (3) and (4) is an ethylene chain because it is easy to obtain industrial raw materials when synthesizing the compounds represented by the general formulas (3) and (4). Similarly, R is preferably a hydrogen atom.

  In addition, the q / r ratio q / r in the general formula (4) is 20/80 to 95/5 in terms of storage stability and water dilution when an aqueous epoxy resin composition is used. It is preferable from the point of being excellent, and it is preferable that it is 30 / 70-80 / 20 especially as said ratio.

  A in the general formula (4) is a divalent residue obtained by removing a hydrogen atom from a bifunctional hydroxy compound or a bifunctional carboxylic acid, and the compound represented by the general formula (4) It has a substituent on the aromatic ring from the viewpoint of excellent mechanical properties (strength) of processed products using water-based epoxy resin compositions obtained by using them and adhesion to substrates when used for coatings, etc. It is preferably a residue of bisphenols which may be used, particularly a residue of bisphenol A.

  Although it does not specifically limit as a manufacturing method of bifunctional epoxy group containing resin (b-2) used for the water-based epoxy resin composition of this invention, It is raw material acquisition that it is a manufacturing method of this invention. This is preferable in terms of ease and excellent industrial production.

Hereafter, the manufacturing method of this invention is explained in full detail.
The production method of the present invention preferably starts with synthesizing the novel cationic group-containing bifunctional hydroxy compound (a1) of the present invention represented by the following general formula (5) of the present invention. As the bifunctional hydroxy compound of the present invention, R in the general formula (5) is particularly preferable because the obtained epoxy resin has low viscosity and excellent storage stability when used as an aqueous epoxy resin composition. ₁ , R ₂ , R ₃ , R ₄ are hydrogen atoms, R ₅ , R ₆ , R ₇ , R ₈ are methyl groups, Q is a nitrogen atom, and Y is a chlorine atom or a hydroxyl group preferable.

Wherein _{(5), R 1, R} 2, R 3, R 4, R 5 are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon _{atoms, R 6, R 7, R} 8 Cloudy Each independently an alkyl group having 1 to 4 carbon atoms, R is a hydrogen atom or a methyl group, X is a single bond or an alkylene chain having 1 to 4 carbon atoms, and Q is a nitrogen atom or a phosphorus atom. , Y is a chlorine atom, a bromine atom, an iodine atom or a hydroxyl group. )

  The bifunctional hydroxy compound (a1) represented by the general formula (5) is represented by the following general formula (2)

[In the formula (2), R ₁ , R ₂ , R ₃ , R ₄ and R ₅ may be the same or different, and are a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and X is a single bond or a carbon number. 1 to 4 alkylene chains. ]
It is preferable to manufacture by making the compound (x1) which has a hydroxyl group and a carboxyl group represented by these, and a quaternary onium salt containing epoxy compound (x2) react.

  As the compound (x1) represented by the general formula (2), for example, it has a substituent at an ortho position such as orthocresol, 2,6-xylenol, orthobutylphenol in the presence of no catalyst or a catalyst. It is obtained by reacting a good phenol with a compound containing a carboxyl group and a carbonyl group independent of this in one molecule such as 2-oxopropanoic acid, 3-oxobutanoic acid, 3-acetylpropionic acid, and glyoxylic acid. I can do it. Various catalysts can be used as the catalyst. Examples of the acidic catalyst include inorganic acids such as hydrochloric acid, sulfuric acid and phosphoric acid, organic acids such as methanesulfonic acid, p-toluenesulfonic acid and oxalic acid, and trifluoride. Examples include Lewis acids such as boron, anhydrous aluminum chloride, and zinc chloride. Examples of basic catalysts include alkali (earth) metal hydroxides such as sodium hydroxide, potassium hydroxide, lithium hydroxide, and calcium hydroxide. And alkali metal carbonates such as sodium carbonate and potassium carbonate. Although the usage-amount of these catalysts is not specifically limited, It is preferable to use 0.1-30 weight% with respect to the phenols which may have a substituent in the ortho position used as a raw material. The form of the catalyst is not particularly limited, and may be an aqueous solution or a solid.

  The reaction can be performed in the absence of a solvent or in the presence of an organic solvent. Examples of the organic solvent to be used include methyl cellosolve, ethyl cellosolve, toluene, xylene, methyl isobutyl ketone, and the like. These may be used alone or in combination of two or more. The amount of the organic solvent used is usually 50 to 300% by weight, preferably 100 to 250% by weight, based on the total weight of the raw materials used. The reaction temperature is usually 40 to 180 ° C., and the reaction time is usually 1 to 10 hours. Further, it is preferable to distill off the water produced during the reaction by using a fractionating tube or the like outside the system in order to carry out the reaction quickly.

  Moreover, when the coloring of the compound (x1) obtained by the said reaction is large, in order to suppress it, you may add antioxidant and a reducing agent. Although it does not specifically limit as said antioxidant, For example, hindered phenol type compounds, such as a 2, 6- dialkyl phenol derivative, a bivalent sulfur type compound, a phosphite type compound containing a trivalent phosphorus atom, etc. Can be mentioned. The reducing agent is not particularly limited, and examples thereof include hypophosphorous acid, phosphorous acid, thiosulfuric acid, sulfurous acid, hydrosulfite, and salts thereof.

  After completion of the reaction, the reaction mixture is neutralized or washed with water until the pH value of the reaction mixture becomes 3 to 7, preferably 5 to 7. There are no particular restrictions on the method of neutralization treatment or water washing treatment. For example, when an acidic catalyst is used, basic substances such as sodium hydroxide, potassium hydroxide, sodium carbonate, ammonia, triethylenetetramine, aniline, When a neutral catalyst is used, acidic substances such as hydrochloric acid, sodium hydrogen phosphate, and oxalic acid can be used as a neutralizing agent.

  After the neutralization or washing treatment, the compound (x1) can be obtained by distilling off the solvent and unreacted substances under heating under reduced pressure.

Among the compounds (x1) obtained in this manner, the bifunctional epoxy resin obtained is excellent in water solubility and excellent in storage stability when made into an aqueous epoxy resin composition, and the corrosion resistance / mechanical properties of the resulting compound. From the viewpoint of excellent strength and the like, it is preferable that R ₁ , R ₂ , R ₃ , and R _{4 in the} general formula (2) are hydrogen atoms and R ₅ is a methyl group, and the general formula (2 X is preferably an ethylene chain, and most preferably diphenolic acid. In addition, since diphenolic acid is commercially available from Otsuka Chemical Co., Ltd., the commercially available product can be used as it is.

  Examples of the quaternary onium salt-containing epoxy compound (x2) include, for example, glycidyl acrylate, glycidyl methacrylate, epoxy group-containing vinyl monomers such as alicyclic monoepoxide having a vinyl group, and acrylic acid having a quaternary onium salt. Examples thereof include a copolymer of a monomer and a vinyl monomer having a quaternary onium salt such as a methacrylic acid monomer having a quaternary onium salt, and a compound represented by the following general formula (6).

[In Formula (6), R is a hydrogen atom or a methyl group, Q is a nitrogen atom or a phosphorus atom, Y is a chlorine atom, a bromine atom, or an iodine atom, and R ₆ , R ₇ , and R ₈ are the same. However, it is a C1-C4 alkyl group which may differ. ]

  Examples of the alicyclic monoepoxide having a vinyl group include Celoxide 2000 (trade name: manufactured by Daicel Chemical Industries, Ltd.). Examples of the acrylic acid monomer having a quaternary onium salt include, for example, DMAEA-Q ( Kojin Co., Ltd., N, N-dimethylaminoethyl acrylate-methyl chloride salt, 79% aqueous solution) and DMAPAA-Q (Kojin Co., Ltd., N, N-dimethylaminopropylacrylamide-methyl chloride salt, 75% Aqueous solution) and the like.

  Further, a compound obtained by copolymerizing an epoxy group-containing vinyl monomer with an acrylic monomer having acrylamide or tertiary amine and then quaternized with an alkyl halide can also be used.

Among these, it is preferable to use the compound represented by the general formula (6) from the viewpoint that the obtained bifunctional epoxy resin is excellent in water solubility and excellent in storage stability when used as an aqueous epoxy resin composition. In particular, from the viewpoint of easy availability, a compound in which R ₁ , R ₂ and R _{3 in the} general formula (6) are the same or different linear alkyl groups having 1 to 4 carbon atoms is used. SY-GTA80 [trade name, manufactured by Sakamoto Pharmaceutical Co., Ltd., NV = 80, wherein R is a hydrogen atom, Q is a nitrogen atom, R ₁ , R ₂ , R ₃ are methyl groups, and X is a chlorine atom] % Aqueous solution, epoxy equivalent (solid content): 151 g / eq] is most preferred.

  As a reaction method of the compound (x1) represented by the general formula (2) and the quaternary onium salt-containing epoxy compound (x2), a carboxyl group in the compound (x1) and the quaternary onium salt-containing epoxy are used. Any compound that preferentially reacts with the glycidyl group in the compound (x2) may be used, and the reaction can be carried out in the absence of a catalyst or in the presence of a catalyst. When a catalyst is used, the compound represented by the general formula (2) A side reaction in which the phenolic hydroxyl group in (x1) and the glycidyl group in the quaternary onium salt-containing epoxy compound (x2) react easily occurs, and the polymerization reaction of the quaternary onium salt-containing epoxy compound (x2) occurs. In view of the tendency to proceed, a method of reacting in the absence of a catalyst is preferable.

  However, depending on the combination of the compound (x1) and the epoxy compound (x2), there may be a problem that the reaction does not proceed rapidly, and an appropriate catalyst can be used. Examples of catalysts that can be used include alkali (earth) metal hydroxides such as sodium hydroxide, potassium hydroxide, lithium hydroxide and calcium hydroxide, alkali metal carbonates such as sodium carbonate and potassium carbonate, and butoxy lithium. Metal alcoholates such as methoxysodium, Lewis acids such as lithium chloride and aluminum chloride, and mixtures of Lewis acids and Lewis bases such as triphenylphosphine oxide, chlorides such as tetramethylammonium, tetraethylammonium, tetrabutylammonium and benzyltributylammonium , Bromide, iodide, tetramethylphosphonium, tetraethylphosphonium, tetrabutylphosphonium, benzyltributylphosphonium chloride, bromide, iodide, acetate, etc. Tertiary amines such as quaternary ammonium salts, triethylamine, N, N-dimethylbenzylamine, 1,8-diazabicyclo [5.4.0] undecene-7, 1,4-diazabicyclo [2.2.2] octane And imidazoles such as 2-ethyl-4-methylimidazole and 2-phenylimidazole. Two or more kinds of catalysts may be used in combination. The amount of the catalyst used is usually in the range of 5 ppm (weight basis) to 2 wt%, preferably 20 ppm (weight basis) to 0.5 wt%, relative to the compound (x1). The form of these catalysts is not particularly limited, and the catalyst may be diluted with an appropriate solvent, used in the form of an aqueous solution, or used in a solid form.

  The reaction temperature for carrying out the reaction is preferably in the range of 30 to 70 ° C. from the viewpoint of an appropriate reaction rate and suppression of side reactions.

  The reaction can be performed in the absence of a solvent or in the presence of a solvent. As the solvent, in the general formula (5), the compound (x1) and the epoxy compound (x2) are uniformly dissolved, and the compound (x1), the epoxy compound (x2), and the reaction product are used. It is not particularly limited as long as it is inactive with respect to the difunctional hydroxy compound (a1) represented, for example, water, methanol, ethanol, isopropanol, n-butanol, isobutanol and other alcohols, toluene, Hydrocarbons such as xylene, cyclohexane, decalin, esters such as ethyl acetate, n-butyl acetate, isobutyl acetate, n-amyl acetate, ethoxyethyl propionate, 3-methoxybutyl acetate, methoxypropyl acetate, cellosolve acetate, Methyl cellosolve, ethyl cellosolve, propyl cellosolve, butyl Cellosolves such as rosolve, isobutyl cellosorb, tert-butyl cellosorb, glymes such as monoglyme, diglyme, triglyme, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, propylene glycol monoisobutyl ether, propylene glycol mono Examples include aprotic polar solvents such as -tert-butyl ether, acetonitrile, dimethyl sulfoxide, dimethylformamide, and the like. These can be used either as a single solvent or as a mixed solvent of two or more. Among these, since the reaction product solution obtained can be used as it is as the aqueous epoxy resin composition of the present invention, water alone, alcohols, cellosolves, glymes, aprotic polar solvents, Or it is preferable to use each mixed solvent.

  The reaction ratio between the compound (x1) and the epoxy compound (x2) is not particularly limited, but the ratio of the carboxyl group equivalent in the compound (x1) to the epoxy equivalent in the epoxy compound (x2) (x1) / When (x2) is small, a carboxyl group remains, and this carboxyl group and epihalohydrin (a2) react during the reaction of the resulting bifunctional hydroxy compound (a1) and epihalohydrin (a2), which will be described later. It becomes a trifunctional epoxy resin and tends to form a fragile branched structure in the end, and when the ratio is large, the amount of unreacted epoxy compound (x2) increases, and the resulting bifunctional hydroxy compound to be described later is obtained. During the reaction of the compound (a1) with the epihalohydrin (a2), the phenolic hydroxyl group in the bifunctional hydroxy compound (a1) Side reaction with the xylene compound (x2) occurs, and as a result, a monofunctional epoxy resin in which one end of the molecule is an epoxy group and one is an onium salt structure, or a non-functional structure in which both ends are an onium salt structure The ratio (x1) / (x2) is usually 0 in view of the fact that a resin that does not contribute to three-dimensional crosslinking is likely to be mixed by reaction with the amine-based curing agent (B) described later. .8 or more and 2 or less, preferably 1 or more and 1.5 or less.

  Even if the cation group-containing bifunctional hydroxy compound (a1) obtained by the reaction is used as it is, removal of the solvent, unreacted epoxy compound (x2), by-product (polymerized product, etc.) as necessary. A purification step such as removal may be performed.

  Moreover, when the coloring of the cation group containing bifunctional hydroxy compound (a1) obtained is large, in order to suppress it, you may add antioxidant and a reducing agent. Although it does not specifically limit as antioxidant, For example, a hindered phenol type compound, such as a 2, 6- dialkylphenol derivative, a bivalent sulfur type compound, a phosphite type compound containing a trivalent phosphorus atom, etc. are mentioned. Can do. The reducing agent is not particularly limited, and examples thereof include hypophosphorous acid, phosphorous acid, thiosulfuric acid, sulfurous acid, hydrosulfite, and salts thereof.

  The bifunctional hydroxy compound (a1) obtained by the above reaction is useful as a raw material for the bifunctional epoxy group-containing resin (b-2) used in the present invention (raw raw material for reaction with epihalohydrin and an extender for general-purpose epoxy resins). It is.

  The production method of the bifunctional epoxy group-containing resin (b-2) of the present invention is obtained by reacting the compound (x1), the epoxy compound (x2) and the epihalohydrin (a2). Preferably, a method using the bifunctional hydroxy compound (a1) and epihalohydrin (a2) as raw materials is preferable from the viewpoint of an industrial production method.

Examples of the production method include the following.
First, as a method of obtaining the bifunctional epoxy resin represented by the general formula (3),
(I) a method of reacting the bifunctional hydroxy compound (a1) with an epihalohydrin (a2) (so-called one-step method),
(II) A method (so-called two-stage method) in which the bifunctional epoxy resin obtained in (I) is further subjected to an extension reaction using the bifunctional hydroxy compound (a1),
Is mentioned.

Furthermore, as a method of obtaining the bifunctional epoxy group-containing resin represented by the general formula (4),
(III) A mixture of the bifunctional hydroxy compound (a1) and a compound (a3) having two hydroxyl groups or carboxyl groups in one molecule other than the (a1), and an epihalohydrin (a2). A reaction method (co-condensation reaction),
(IV) A method of subjecting the bifunctional epoxy resin obtained in (I) to an elongation reaction using a compound (a3) having two hydroxyl groups or carboxyl groups in one molecule other than the above (a1),
(V) A method in which a bifunctional epoxy resin other than the bifunctional epoxy resin of the present invention [cationic group-free bifunctional epoxy resin (a4)] is subjected to an extension reaction using the bifunctional hydroxy compound (a1). ,
Is mentioned.

  (I) The reaction method of the said bifunctional hydroxy compound (a1) and epihalohydrin (a2) can use the reaction which obtains an epoxy resin by reaction of phenols and epihalohydrin conventionally. For example, 0.3 to 10 mol of epihalohydrin (a2) is added to 1 mol of the aromatic hydroxy group in the bifunctional hydroxy compound (a1), and further, 0.1 mol to 1 mol of the aromatic hydroxy group. A method of reacting at a temperature of 20 to 120 ° C. for 0.5 to 10 hours while adding or gradually adding 9 to 2.0 mol of a base can be mentioned. As the base, a solid or an aqueous solution thereof may be used. When an aqueous solution is used, it is continuously added, and water and epihalohydrin (a2) are continuously added from the reaction mixture under reduced pressure or normal pressure. The liquid may be further separated to remove water, and the epihalohydrin (a2) may be continuously returned to the reaction mixture.

  In the methods (II) and (IV) described later, that is, when the resulting bifunctional epoxy resin is subjected to an extension reaction, 2 to 10 mol of epihalohydrin (a2) is added to 1 mol of the aromatic hydroxy group. In order to give an appropriate molecular weight for expressing the excellent curability and physical properties of the cured product of the resulting epoxy resin composition, it is preferable to use an epihalohydrin (a2) with respect to 1 mol of the aromatic hydroxy group. ) Is preferably used in an amount of 0.3-1 mol.

  In addition, when industrial production is performed, all of the epihalohydrin (a2) used for preparation is new in the first batch of epoxy resin production. However, in the subsequent batch, the reaction with epihalohydrin recovered from the crude reaction product is performed. It is preferable to use in combination with new epihalohydrins corresponding to the amount consumed and consumed.

  The epihalohydrin (a2) is not particularly limited, and examples thereof include epichlorohydrin, epibromohydrin, β-methylepichlorohydrin, and the like, and it is preferable to use epichlorohydrin because it is easily available industrially.

  The base is not particularly limited, and examples thereof include alkaline earth metal hydroxides, alkali metal carbonates, and alkali metal hydroxides. In particular, alkali metal hydroxides are preferable from the viewpoint of excellent catalytic activity of the epoxy resin synthesis reaction, and examples thereof include sodium hydroxide and potassium hydroxide. In use, these bases may be used in the form of an aqueous solution of about 10 to 55% by weight or in a solid form.

  Moreover, the reaction rate in the synthesis | combination of an epoxy resin can be raised by using an organic solvent together. Examples of such organic solvents include, but are not limited to, ketones such as acetone and methyl ethyl ketone, and alcohols such as water, methanol, ethanol, 1-propyl alcohol, isopropyl alcohol, 1-butanol, secondary butanol, and tertiary butanol. Cellosolves such as methyl cellosolve, ethyl cellosolve, propyl cellosolve, butyl cellosolve, isobutyl cellosolve, tert-butyl cellosolve, glymes such as monoglyme, diglyme, triglyme, tetrahydrofuran, 1,4-dioxane, 1,3-dioxane, di Examples include ethers such as ethoxyethane, aprotic polar solvents such as acetonitrile, dimethyl sulfoxide, and dimethylformamide. These organic solvents may be used alone, or two or more kinds may be used in combination as appropriate in order to adjust the polarity. Among these, since the reaction product solution obtained can be used as it is as the aqueous epoxy resin composition of the present invention, water alone, alcohols, cellosolves, glymes, aprotic polar solvents, Or it is preferable to use each mixed solvent.

After washing the reaction product obtained in the above reaction with water, if necessary, unreacted epihalohydrin (a2) and the organic solvent to be used in combination are distilled off by distillation under heating and reduced pressure. Further, in order to obtain an epoxy resin with less hydrolyzable halogen, the obtained epoxy resin is again dissolved in an organic solvent such as toluene, methyl isobutyl ketone, methyl ethyl ketone, and alkali metal hydroxide such as sodium hydroxide or potassium hydroxide. Further reaction can be carried out by adding an aqueous solution of the product. At this time, a phase transfer catalyst such as a quaternary ammonium salt or crown ether may be present for the purpose of improving the reaction rate. When the phase transfer catalyst is used, the amount used is preferably in the range of 0.1 to 3.0% by weight based on the epoxy resin used. After completion of the reaction, the generated salt is removed by filtration, washing with water, and a high-purity epoxy resin can be obtained by distilling off a solvent such as toluene and methyl isobutyl ketone under heating and reduced pressure. The amount of halogen ions in the epoxy resin obtained in this way is not more than a few ppm regardless of the type of counter ion in the epoxy compound (x2) used as a raw material. It has been found that the counter ion of the quaternary onium salt is OH ⁻ due to the alkali used as the catalyst. That the counter ion is OH ⁻ is useful as an electronic material or an aqueous material, and has high industrial value.

  (II) As a method of subjecting the bifunctional epoxy resin obtained by the above-mentioned method (I) to an extension reaction using the bifunctional hydroxy compound (a1), for example, heating and stirring at 100 to 220 ° C. The method of doing is mentioned. In this reaction, the reaction can be carried out in the presence of an appropriate organic solvent. At this time, a catalyst may be used as necessary. The catalyst is not particularly limited, and examples thereof include onium salts, phosphines, alkali metal hydroxides, and the like. The reaction ratio between the bifunctional epoxy resin used as a raw material and the bifunctional hydroxy compound (a1) is not particularly limited, and may be appropriately set according to the desired epoxy equivalent (molecular weight). preferable.

  The organic solvent that can be used at the time of the reaction is not particularly limited as long as the raw materials and products are uniformly dissolved and inert, and examples thereof include toluene, xylene, cyclohexane, and decalin. Hydrocarbons, ethyl acetate, n-butyl acetate, isobutyl acetate, n-amyl acetate, ethoxyethyl propionate, 3-methoxybutyl acetate, methoxypropyl acetate, cellosolve acetate and other esters, methanol, ethanol, isopropanol, n -Alcohols such as butanol and isobutanol, cellosolves such as methyl cellosolve, ethyl cellosolve, propyl cellosolve, butyl cellosolve, isobutyl cellosolve, tert-butyl cellosolve, and glymes such as monoglyme, diglyme and triglyme Propylene glycol monoalkyl ethers such as propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, propylene glycol monoisobutyl ether, propylene glycol mono tert-butyl ether, polar solvents such as methyl ethyl ketone, acetone, dimethylformamide and dimethylacetamide Etc., water can also be used, and these may be used alone or in combination of two or more.

  (III) A reaction of a mixture of the bifunctional hydroxy compound (a1) with a compound (a3) having two hydroxyl groups or carboxyl groups in one molecule other than the (a1), and an epihalohydrin (a2) About the method to make, it is based on the method of the above-mentioned (I), and it is required according to the solubility, molecular weight, and use of the bifunctional epoxy resin obtained by using the said compound (a3) together. It is possible to adjust the flexibility, adhesion, corrosion resistance, etc. of a simple workpiece. In particular, the bifunctional hydroxy compound (a1) and the compound (a3) having two hydroxyl groups or carboxyl groups in the molecule from the viewpoint of excellent storage stability and water dilution when used as an aqueous epoxy resin composition The molar ratio is preferably 20/80 to 95/5, particularly preferably 30/70 to 80/20.

  The compound (a3) that can be used here is not particularly limited. For example, divalent phenols such as resorcin, hydroquinone, and catechol, which may have a substituent on the aromatic ring, Bisphenols such as bisphenol A, bisphenol F, bisphenol AD, tetrabromobisphenol A, biphenols such as biphenol and tetramethylbiphenol, 2,7-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, etc. Dihydroxynaphthalenes, compounds obtained by hydrogenating aromatic nuclei of the above-mentioned bifunctional phenols, etc., and examples of carboxylic acids include aliphatic compounds such as adipic acid, sebacic acid, azelaic acid, decanoic acid, succinic acid, and glutaric acid. Divalent carboxylic acid, phthalic acid, Sofutaru acid, terephthalic acid, include aromatic dicarboxylic acids or their hydrogenated products such as naphthalene dicarboxylic acid, can also be used as a mixture of two or more in combination.

  Among these, the substituent on the aromatic ring is excellent in terms of mechanical properties (strength) of a processed product using the obtained aqueous epoxy resin composition and excellent adhesion to a base material when used for coatings. It is preferable to use bisphenols which may have bisphenol A, and it is particularly preferable to use bisphenol A.

(IV) A method of subjecting the bifunctional epoxy resin obtained in (I) to an extension reaction using a compound (a3) having two hydroxyl groups or carboxyl groups in one molecule other than the above (a1), This is in accordance with the method (II) described above. The compound (a3) that can be used here and preferred ones thereof are the same as those described in (III) above. The reaction ratio between the bifunctional epoxy resin and the compound (a3) is not particularly limited, and the solubility and molecular weight in water, the flexibility and adhesion of the work piece required depending on the application, It is preferable to select appropriately according to the corrosion resistance and the like. In particular, as a molar ratio of the bifunctional epoxy resin and the compound (a3) having two hydroxyl groups or carboxyl groups in the molecule from the viewpoint of excellent storage stability and water dilution when used as an aqueous epoxy resin composition. Is preferably 20/80 to 95/5, particularly preferably 30/70 to 80/20.

  (V) A bifunctional epoxy resin other than the bifunctional epoxy resin of the present invention [cationic group-free bifunctional epoxy resin (a4)] is also subjected to an extension reaction using the bifunctional hydroxy compound (a1). The method is the same as that described in (II) above.

  The cation group-free bifunctional epoxy resin (a4) that can be used here is not particularly limited, and examples thereof include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, and biscresol. F-type epoxy resin, bisphenol S-type epoxy resin, condensate of diaminodiphenylmethane and epihalohydrin, etc., ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, polyethylene glycol, polypropylene glycol, polytetramethylene Examples include condensates of ether glycol, trimethylolpropane and epihalohydrin, and these may be used alone or in combination of two or more. Among these, it is preferable to use a bisphenol A type epoxy resin or a bisphenol F type epoxy resin from the viewpoint that the reactivity is good and the processed product using the obtained aqueous epoxy resin composition has good corrosion resistance.

  The reaction ratio of these cation group-free bifunctional epoxy resin (a4) and the bifunctional hydroxy compound (a1) is not particularly limited, depending on solubility in water, molecular weight, and use. It is preferable to select appropriately according to the required flexibility, adhesion, corrosion resistance, etc. of the workpiece. In particular, the molar ratio of the bifunctional hydroxy compound (a1) to the cationic functional group-free bifunctional epoxy resin (a4) is 20 from the viewpoint of excellent storage stability and water dilution when used as an aqueous epoxy resin composition. / 80 to 95/5 is preferable, and 30/70 to 80/20 is particularly preferable.

  The products obtained in the above reactions (I) to (V) have high purity by performing purification steps such as deactivation of the catalyst, distillation of the solvent and unreacted raw materials, and drying as necessary. It can be.

  The amine-based curing agent (B) used in the present invention is a so-called epoxy adduct type curing obtained by reacting the polyamine compound (b-1) with the bifunctional epoxy group-containing resin (b-2). Although it is an agent, when this reaction is carried out, an adduct reaction is carried out using a conventionally known epoxy resin in combination with the bifunctional epoxy group-containing resin (b-2) within a range not impairing the effects of the present invention. It is also possible to do this.

  The reaction between the polyamine compound (b-1) and the aforementioned bifunctional epoxy group-containing resin (b-2) can be carried out under conditions conventionally known as addition reactions. At this time, it can be carried out in the absence of a solvent or in an appropriate solvent, and as a solvent that can be used, the compound (b-1) and the bifunctional epoxy group-containing resin (b-2) are further added as necessary. It is not particularly limited as long as it uniformly dissolves other epoxy resins used together and is inactive. For example, alcohols such as water, methanol, ethanol, isopropanol, n-butanol, and isobutanol, Hydrocarbons such as toluene, xylene, cyclohexane and decalin, esters such as ethyl acetate, n-butyl acetate, isobutyl acetate, n-amyl acetate, ethoxyethyl propionate, 3-methoxybutyl acetate, methoxypropyl acetate and cellosolve acetate , Methyl cellosolve, ethyl cellosolve, propyl cellosolve, butyl celloso Cellosolves such as butyl, isobutyl cellosolve, tert-butyl cellosorb, glymes such as monoglyme, diglyme, triglyme, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, propylene glycol monoisobutyl ether, propylene glycol mono A tert-butyl ether etc. are mentioned, It can use also as 1 type, or 2 or more types of mixed solvents. Among these, the solution of the reaction product obtained can be used as it is as the aqueous epoxy resin composition of the present invention, so that water alone or a mixed solvent of water and alcohols, cellosolves and glymes is used. It is preferable to use it.

  The reaction ratio between the polyamine compound (b-1) and the epoxy group-containing resin (b-2) is not particularly limited, but water dispersibility when obtained as an aqueous epoxy resin composition, and Epoxy group-containing resin (b-2) containing other epoxy resin with respect to 1 mol of active hydrogen of the amino group in polyamine compound (b-1) from the point which is excellent in the balance with the anticorrosion property of the cured coating film obtained It is preferable to use it so that the total amount of epoxy groups in it may be 0.02 to 0.30 mol, and it is particularly preferable to use it so as to be 0.05 to 0.20 mol. Although it does not specifically limit as reaction conditions in this reaction, Usually, 40-130 degreeC, Preferably it is 60-120 degreeC, It can carry out by stirring for 1 to 6 hours, Preferably it is 2 to 4 hours.

  The amine-based curing agent (B) obtained by the reaction may be used as it is, or may be subjected to a purification step such as removal of a solvent as necessary, and may be further homogenized by adding water. good. Two or more amine curing agents (B) may be used in combination in the aqueous epoxy resin composition of the present invention.

  The amine-based curing agent (B) obtained by the above reaction exhibits water dispersibility by itself, but an organic acid such as acetic acid may be used as necessary to give better water dispersibility. The amino group may be neutralized by water dispersion.

  The aqueous epoxy resin composition of the present invention is not limited in any way other than using the epoxy resin (A) and the amine-based curing agent (B), and within the range not impairing the effects of the present invention. Epoxy resin curing agents, film-forming aids, other polyester aqueous resins, acrylic aqueous resins, etc., reactive diluents, non-reactive diluents, fillers, reinforcing agents, pigments, plasticizers, thixotropic agents, Additives such as anti-repellent agents, anti-sagging agents, spreading agents, antifoaming agents, curing accelerators, ultraviolet absorbers, and light stabilizers can be used in combination as appropriate.

The other curing agent is not particularly limited, and may be various amine compounds, amide compounds, phenolic compounds as long as they can be cured and reacted with the epoxy group in the epoxy resin (A). Any curing agent such as a compound can be used. Examples of amine compounds include diaminodiphenylmethane, diethylenetriamine, triethylenetetramine, diaminodiphenylsulfone, isophoronediamine, imidazole, BF ₃ -amine complexes, guanidine derivatives, and the like. Examples of amide compounds include dicyandiamide and linolenic acid. Polyamide resins synthesized from ethylenediamine and the like, and phenolic compounds include phenol novolac resins, cresol novolac resins, aromatic hydrocarbon formaldehyde resin-modified phenol resins, dicyclopentadiene phenol addition type resins, Phenol aralkyl resin (commonly known as zylock resin), naphthol aralkyl resin, trimethylol methane resin, tetraphenylol ethane resin, naphthol novolak Fatty, naphthol-phenol co-condensed novolak resin, naphthol-cresol co-condensed novolak resin, biphenyl-modified phenol resin (polyhydric phenol compound in which phenol nucleus is linked by bismethylene group), biphenyl-modified naphthol resin (phenol nucleus is linked by bismethylene group) Polyhydric naphthol compounds), aminotriazine-modified phenol resins (polyhydric phenol compounds in which phenol nuclei are linked with melamine, benzoguanamine, etc.), and modified products thereof.

  The blending amount of the epoxy resin (A) and the amine curing agent (B) in the aqueous epoxy resin composition of the present invention is not particularly limited, but from the point that the properties of the resulting cured product are good. The amount of active groups in the curing agent containing the amine curing agent (B) is preferably 0.7 to 1.2 equivalents relative to 1 equivalent of the total epoxy groups in the epoxy resin (A).

  Examples of the film-forming aid include lower alcohols such as methanol, ethanol and isopropanol, cellosolves such as methyl cellosolve, ethyl cellosolve, n-propyl cellosolve, isopropyl cellosolve, butyl cellosolve, isobutyl cellosolve, and tert-butyl cellosolve, Glymes such as monoglyme, diglyme, triglyme, propylene glycol monomethyl ether, polypropylene glycol monoethyl ether, propylene glycol monopropyl ether, polypropylene glycol mono n-butyl ether, polypropylene glycol monoisobutyl ether, polypropylene glycol mono-tert-butyl ether, and other propylene Examples include glycol monoalkyl ethers and diacetone alcohol It is.

  Various curing accelerators can be used, and examples thereof include phosphorus compounds, tertiary amines, imidazoles, organic acid metal salts, Lewis acids, and amine complex salts.

  The aqueous epoxy resin composition of the present invention can be obtained by emulsifying and / or dispersing in water together with the epoxy resin (A), the amine-based curing agent (B) and additives used as necessary. At this time, after emulsifying and / or dispersing the epoxy resin (A) and the amine-based curing agent (B), respectively, the two are mixed, and one is emulsified and / or dispersed while the other is added to emulsify and Either a method of dispersing and / or a method of emulsifying and / or dispersing both at the same time can be applied.

  The aqueous epoxy resin composition obtained as described above is coated by an appropriate method such as brush coating, roller, spray, spatula coating, press coating, doctor blade coating, electrodeposition coating, dip coating, or the like. It is used as an undercoating or intermediate coating, filler, sealing material, coating material, sealing material, mortar coating material, etc. by applying to materials, and is particularly useful as an anticorrosion coating for metals because of its excellent anticorrosion properties .

  Although it does not restrict | limit especially as a use of the water-based epoxy resin composition of this invention, For example, it can use suitably as a coating material, an adhesive agent, a fiber sizing agent, a concrete primer, etc.

  When the aqueous epoxy resin composition of the present invention is used for coating applications, it is preferable to incorporate various fillers such as rust preventive pigments, colored pigments, extender pigments, various additives, and the like as necessary. Examples of the anticorrosion pigment include zinc powder, aluminum phosphomolybdate, zinc phosphate, aluminum phosphate, barium chromate, aluminum chromate, graphite and other scaly pigments, and the coloring pigment includes carbon black, oxidation pigment, etc. Examples thereof include titanium, zinc sulfide, and bengara. Examples of extender pigments include barium sulfate, calcium carbonate, talc, and kaolin. As a compounding quantity of these fillers, it is 10-70 weight part with respect to a total of 100 weight part of an epoxy resin (A), an amine hardening | curing agent (B), and the other hardening | curing agent mix | blended as needed. Is preferable from the viewpoints of coating film performance, coating workability and the like.

  The method of blending the filler and additive into the aqueous epoxy resin composition of the present invention is not particularly limited. For example, the filler and additive are sufficiently kneaded and uniformly dispersed using an apparatus such as a mixing mixer or a ball mill. Prepared in advance, kneaded and dispersed epoxy resin previously emulsified with the above-mentioned apparatus, prepared with water to a desired concentration, and mixed with an amine curing agent. Can be obtained.

  The coating method in the case of using the aqueous epoxy resin composition of the present invention for coating is not particularly limited, and may be performed by roll coating, spraying, brushing, spatula, bar coater, dip coating, electrodeposition coating method. As the processing method, room temperature drying to heat curing can be performed. In the case of heating, a coating film can be obtained by reacting at 50 to 250 ° C., preferably 60 to 230 ° C. for 2 to 30 minutes, preferably 5 to 20 minutes.

  In addition, when the aqueous epoxy resin composition of the present invention is used as an adhesive, it is not particularly limited, and can be performed by applying the sprayed, brushed, or spatula to the base material, and then matching the adhesive surface of the base material. In addition, the bonding portion can form a strong adhesive layer by fixing or pressing the periphery. Steel plates, concrete, mortar, wood, resin sheets, resin films are suitable as the base material, and various surface treatments such as physical treatment such as polishing, electrical treatment such as corona treatment, and chemical treatment such as chemical conversion treatment are performed as necessary. More preferably, it is applied after application.

  Further, when the aqueous epoxy resin composition of the present invention is used as a fiber sizing agent, it can be carried out without any particular limitation. For example, it is applied to a fiber immediately after spinning using a roller coater and wound as a fiber strand. Thereafter, a method of drying is mentioned. The fiber to be used is not particularly limited. For example, inorganic fibers such as glass fiber, ceramic fiber, asbestos fiber, carbon fiber, and stainless steel fiber, natural fibers such as cotton and hemp, synthetic fibers such as polyester, polyamide, and urethane. Examples of the shape of the base material include short fibers, long fibers, yarns, mats, and sheets. The amount used as the fiber sizing agent is preferably 0.1 to 2% by weight as the resin solid content with respect to the fiber.

  Moreover, when using the water-based epoxy resin composition of this invention as a concrete primer, it is not specifically limited, It can carry out with a roll, a spray, a brush, a spatula, and a scissors.

  Hereinafter, the present invention will be described in more detail with reference to examples. In the examples, “parts” and “%” are based on weight unless otherwise specified.

<Example of epoxy resin emulsion synthesis>
Synthesis example 1
500 g of EPICLON 1055 (manufactured by Dainippon Ink and Chemicals, BPA type solid epoxy resin) was dissolved in 47.5 g of benzyl alcohol and 47.5 g of methoxypropanol at 100 ° C. After dissolution, the temperature was lowered to 50-60 ° C., and 40 g of Newcol 780 (60) (manufactured by Nippon Emulsifier Co., Ltd.) was added and sufficiently dissolved. After dissolution, water was added in portions while stirring at 50-60 ° C. at high speed to obtain an emulsion having a nonvolatile content of 55%. The obtained epoxy resin emulsion (A-1) had an epoxy equivalent (solution value) of 930 g / eq and a viscosity (25 ° C.) of 2350 mPa · s.

<Synthesis example of epoxy group-containing resin for adduct>
Synthesis example 2
A diphenolic acid (hydroxyl equivalent 143 g / eq, carboxyl equivalent 286 g / eq, Otsuka Chemical Co., Ltd.) was added to a four-necked flask equipped with a thermometer, stirring device, dropping funnel, cooling pipe, nitrogen gas introduction pipe, and separation cock at the bottom. Co., Ltd.) 286 parts, SY-GTA80 (glycidyl group-containing quaternary onium salt-80% aqueous solution, Sakamoto Yakuhin Kogyo Co., Ltd.) 227 parts and isopropyl alcohol 120 parts, heated to 50 ° C. and stirred uniformly It was set as the solution. Furthermore, the cation group containing bifunctional hydroxy compound was obtained by making it react at the same temperature for 4 hours. Subsequently, 370 parts (4 moles) of epichlorohydrin were charged and dissolved while heating to 40 ° C. with stirring. Thereafter, 8 parts (0.1 mol) of a 49% aqueous sodium hydroxide solution was added and reacted for 4 hours while purging with nitrogen gas. Subsequently, it heated to 50 degreeC and 100 parts (1.2 mol) of 49% sodium hydroxide aqueous solution was dripped over 5 hours. Thereafter, 157 parts of water was added to dissolve the produced salt, and then the saturated saline was discarded from the lower separation cock. Unreacted epichlorohydrin was distilled off under atmospheric pressure to a flask temperature of 130 ° C., and then the salt remaining in the reaction solution was filtered off. Unreacted epichlorohydrin was further distilled off from the filtrate under reduced pressure at a flask temperature of 130 ° C. to obtain a bifunctional epoxy group-containing resin (b-2-1) having an epoxy equivalent of 403 g / eq.

Synthesis example 3
A diphenolic acid (hydroxyl equivalent 143 g / eq, carboxyl equivalent 286 g / eq, Otsuka Chemical Co., Ltd.) was added to a four-necked flask equipped with a thermometer, stirring device, dropping funnel, cooling pipe, nitrogen gas introduction pipe, and separation cock at the bottom. Co., Ltd.) 286 parts, SY-GTA80 (glycidyl group-containing quaternary onium salt-80% aqueous solution, Sakamoto Yakuhin Kogyo Co., Ltd.) 227 parts and isopropyl alcohol 120 parts, heated to 50 ° C. and stirred uniformly It was set as the solution. Furthermore, the cation group containing bifunctional hydroxy compound was obtained by making it react at the same temperature for 4 hours. Next, 228 parts of bisphenol A and 1480 parts (4 mol) of epichlorohydrin were charged and dissolved while heating and stirring to 40 ° C. Thereafter, 33 parts (0.1 mol) of a 49% aqueous sodium hydroxide solution was added with nitrogen gas purge, and the reaction was allowed to proceed for 4 hours. Subsequently, it heated to 50 degreeC and 400 parts (1.2 mol) of 49% sodium hydroxide aqueous solution was dripped over 5 hours. Thereafter, 564 parts of water was added to dissolve the produced salt, and then the saturated saline was discarded from the lower separation cock. Unreacted epichlorohydrin was distilled off under atmospheric pressure to a flask temperature of 130 ° C., and then the salt remaining in the reaction solution was filtered off. Unreacted epichlorohydrin was further distilled off from the filtrate at a flask temperature of 130 ° C. under reduced pressure to obtain a bifunctional epoxy resin (b-2-2) having an epoxy equivalent of 277 g / eq.

<Synthesis example of amine curing agent>
Synthesis example 4
A four-necked flask equipped with a thermometer, a stirrer, a condenser, and a nitrogen inlet was charged with 146 g of triethylenetetramine and 259 g of propyl cellosolve, and the temperature was raised to 40 ° C., and EPICLON 520 (produced by Dainippon Ink & Chemicals, Inc., alkylphenol) Glycidyl ether) was charged in 317 g in 4 portions while paying attention to heat generation, and stirred at 90 ° C. for 3 hours. Thereafter, 314 g of the epoxy group-containing resin (b-2-1) obtained in Synthesis Example 2 (0.166 mol with respect to 1 mol of active hydrogen of the amine adduct) was gradually charged while paying attention to heat generation, at 100 ° C. Stir for 2 hours. Next, after adding 259 g of water, 19 g of acetic acid was added and dissolved uniformly to obtain an amine curing agent (B-1) having a solid content of 60%.

Synthesis example 5
A four-necked flask equipped with a thermometer, a stirrer, a condenser, and a nitrogen inlet was charged with 146 g of triethylenetetramine and 226 g of propyl cellosolve, heated to 40 ° C., and 317 g of EPICLON 520 was charged in four portions while paying attention to heat generation. , And stirred at 90 ° C. for 3 hours. Thereafter, 216 g of the epoxy group-containing resin (b-2-2) obtained in Synthesis Example 3 (0.166 mol with respect to 1 mol of active hydrogen of the amine adduct) was gradually charged while paying attention to heat generation, at 100 ° C. Stir for 2 hours. Next, after adding 227 g of water, 17 g of acetic acid was added and dissolved uniformly to obtain an amine curing agent (B-2) having a solid content of 60%.

Synthesis Example 6
A four-necked flask equipped with a thermometer, a stirrer, a condenser, and a nitrogen inlet was charged with 136 g of metaxylenediamine and 164 g of propyl cellosolve, heated to 40 ° C., and 211 g of EPICLON 520 was charged in four portions while paying attention to heat generation. The mixture was stirred at 90 ° C. for 3 hours. Thereafter, 144 g of an epoxy group-containing resin (b-2-2) (0.166 mol with respect to 1 mol of active hydrogen of the amine adduct) was gradually charged while being careful of heat generation, and stirred at 100 ° C. for 2 hours. Next, after adding 164 g of water, 12 g of acetic acid was added and dissolved uniformly to obtain an amine curing agent (B-3) having a solid content of 60%.

Synthesis example 7
A four-necked flask equipped with a thermometer, a stirrer, a condenser, and a nitrogen inlet was charged with 170 g of isophoronediamine and 175 g of propyl cellosolve, heated to 40 ° C., and 211 g of EPICLON 520 was charged in four portions while paying attention to heat generation. The mixture was stirred at 90 ° C. for 3 hours. Thereafter, 144 g of an epoxy group-containing resin (b-2-2) (0.167 mol with respect to 1 mol of active hydrogen of the amine adduct) was gradually charged while being careful of heat generation, and stirred at 100 ° C. for 2 hours. Next, after adding 175 g of water, 13 g of acetic acid was added and dissolved uniformly to obtain an amine curing agent (B-4) having a solid content of 60%.

Synthesis Example 8
A four-necked flask equipped with a thermometer, stirrer, condenser, and nitrogen inlet was charged with 146 g of triethylenetetramine and 205 g of propyl cellosolve, heated to 40 ° C., and 288 g of EPICLON 520 was charged in four portions while paying attention to heat generation. , And stirred at 90 ° C. for 3 hours. Thereafter, 180.5 g of EPICLON 850 (BPA type liquid epoxy resin, manufactured by Dainippon Ink & Chemicals, Inc.) (0.2 mol with respect to 1 mol of active hydrogen of amine adduct) was gradually charged while paying attention to heat generation. Stir for 2 hours at ° C. Next, after adding 205 g of water, 15 g of acetic acid was added and dissolved uniformly to obtain an amine curing agent (B′-1) having a solid content of 60%.

Synthesis Example 9 <Synthesis of amine curing agent (B′-2), curing agent described in Patent Document 1>
Polypropylene glycol diamine compound (H ₂ N— (C ₃ H ₆₀ ) ₃ —C ₃ H ₆ —NH ₂ ) 124 g and epoxy equivalent in a four-necked flask equipped with a thermometer, stirrer, condenser, and nitrogen inlet 79 g of diglycidyl ether of 315 bisphenol A propylene oxide 5 mol adduct was charged in four portions and stirred at 80 ° C. for 2 hours. Next, 51 g of water was added and sufficiently stirred to obtain an amine-based curing agent (B′-2) having a solid content of 80%.

Examples 1-4 and Comparative Examples 1-2
The components shown in Table 1 were blended in the emulsions and amine curing agents obtained in Synthesis Example 1 and Synthesis Examples 4 to 9 to prepare water-based paints. These aqueous paints were tested for pencil hardness, impact resistance (DuPont impact test), and corrosion resistance (salt spray, 5% sodium hydroxide immersion test, 5% hydrochloric acid immersion test). The results are shown in Table 2.

<Method for preparing specimen>
The adjusted water-based paint is applied to a cold hot-rolled steel sheet (JIS, G, 3141 SPCC.SB, 0.8 × 70 × 150 mm, sandpaper # 240 surface treated) with a bar coater to a dry film thickness of 60 μm. Then, the test piece was prepared by drying at 25 ° C. for 7 days.

  Each evaluation item test was performed according to the following method.

Pencil hardness It implemented based on JISK5400-6.14.

Impact resistance A DuPont impact test (300 g) was performed in accordance with JIS K5400-7.8.
○: No abnormality up to 50 cm Δ: No abnormality up to 45 cm x: No abnormality up to 40 cm

Corrosion resistance A salt spray test (300 hours) was conducted in accordance with JIS K5400-7.8. The test piece was immersed in a 5% aqueous solution of sodium hydroxide and 5% hydrochloric acid at 25 ° C. for 7 days.
○: No abnormality, no rust △: Dandruff, no rust ×: Significant blister, rust

Footnotes in Table 1 Titanium oxide: CR-97 Ishihara Sangyo Co., Ltd. Talc: Talc No. 1 Takehara Chemical Industry Co., Ltd. Calcium carbonate: Brilliant 1500 Shiraishi Kogyo Co., Ltd.

Claims (11)

An aqueous epoxy resin composition containing an epoxy resin (A) and an amine curing agent (B), the amine curing agent (B) comprising a polyamine compound (b-1) and the following general formula (1) An aqueous epoxy resin composition characterized in that it is a compound obtained by reacting a bifunctional epoxy group-containing resin (b-2) having a structure represented by .

[In Formula (1), R ₁ , R ₂ , R ₃ , R ₄ , R ₅ are each independently a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and R ₆ , R ₇ , R ₈ , Each independently an alkyl group having 1 to 4 carbon atoms, R is a hydrogen atom or a methyl group, X is a single bond or an alkylene chain having 1 to 4 carbon atoms, Q is a nitrogen atom or a phosphorus atom, Y is a chlorine atom, a bromine atom, an iodine atom or a hydroxyl group. ] The amine-based curing agent (B) has 0.02 epoxy group in the bifunctional epoxy group-containing resin (b-2) with respect to 1 mol of active hydrogen of the amino group in the polyamine compound (b-1). The aqueous epoxy resin composition according to claim 1, wherein the aqueous epoxy resin composition is reacted by being used so as to have a concentration of ˜0.30 mol. The bifunctional epoxy resin (b-2) is represented by the following general formula (2)

[In the formula (2), R ₁ , R ₂ , R ₃ , R ₄ , R ₅ and X are the same as described above. ]
2. An epoxy resin obtained by reacting a compound (x1) having a hydroxyl group and a carboxyl group, a quaternary onium salt-containing epoxy compound (x2), and an epihalohydrin (a2) represented by formula (1): An aqueous epoxy resin composition. The bifunctional epoxy resin (b-2) is represented by the following general formula (3)

[In Formula (3), R < ₁ > -R < ₈ >, R, X, Q, and Y are the same as the above, p is an average value of the number of repetitions, and is 0-50. ]
The aqueous epoxy resin composition according to claim 1, which is a compound represented by the formula: The bifunctional epoxy resin (b-2) is represented by the following general formula (4)

[In the formula (4), R _{1 to} R ₈ , R, X, Q, and Y are the same as described above, and A is different from the structure represented by the general formula (1). of a residue of a compound having a hydroxyl group or a carboxyl group, q and r is an average number of repetitions, their respective independently q = 0 to 45, a r = 0 to 55. In addition, it shows that each repeating unit has couple | bonded at random. ]
The aqueous epoxy resin composition according to claim 1, which is a compound represented by the formula: The aqueous epoxy resin composition according to claim 5, wherein a ratio q / r between q and r in the general formula (4) is 20/80 to 95/5. The aqueous epoxy resin composition according to claim 5, wherein A in the general formula (4) is a residue of bisphenols. The quaternary onium salt-containing epoxy compound (x2) is represented by the following general formula (5)

(In the formula, R is a hydrogen atom or a methyl group, Q is a nitrogen atom or a phosphorus atom, Y is a chlorine atom, a bromine atom or an iodine atom, and R ₆ , R ₇ and R ₈ are each independently carbon. (It is an alkyl group of formulas 1 to 4. )
The aqueous epoxy resin composition according to claim 3, which is a compound represented by the formula: The aqueous epoxy resin composition according to claim 8, wherein R ₆ , R ₇ , and R _{8 in the} general formula (5) are the same or different linear alkyl groups having 1 to 4 carbon atoms. The aqueous epoxy resin composition according to any one of claims 1 to 7, wherein the polyamine compound (b-1) is an aliphatic polyamine compound. The aqueous epoxy resin composition according to claim 10, wherein the epoxy resin (A) is a bisphenol type epoxy resin.