JP2009035587A - Aqueous resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aqueous resin composition that has excellent substrate adhesivity of a coating film, coating film hardness and excellent storage stability. <P>SOLUTION: The aqueous resin composition comprises an aqueous resin (A) that is produced by reacting (i) a bisphenol A type epoxy resin with (ii) a poly(oxypropylene/oxyethylene)amine, (iii) TDI and ethylene glycol and (iv) (meth)acrylic acid, has a weight-average molecular weight of 10,000-100,000 and contains a urethane bond and a carboxy group and an aqueous medium (B) as essential components. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an aqueous resin composition that can be suitably used for paints, adhesives, fiber sizing agents, concrete primers, and the like because of excellent substrate adhesion and coating film hardness.

  Epoxy resin compositions are generally used in various fields such as paints, adhesives, laminates, and electrical / electronic parts because they are generally excellent in the mechanical properties, corrosion resistance, adhesion and the like of the cured products obtained. Epoxy resins are often diluted in organic solvents and used as compositions. However, due to recent environmental problems, the amount of organic solvents discharged from the compositions is reduced without impairing the above-mentioned high performance of epoxy resins. Was desired.

  In order to meet such demands, the development of high non-volatile differentiation of paints, powder paints, solvent-free paints, and UV / EV curable paints has been developed. The drying line is expected to be diverted and is being actively developed.

  However, the water-based paint has a problem that the drying property of the coating film is poor, the hardness is insufficient, and the water resistance is inferior.

  In order to solve such a problem, for example, a self-dispersion type emulsion in which a bisphenol A type epoxy resin is modified with a polyoxyalkyleneamine compound is disclosed. (For example, refer to Patent Document 1) However, the emulsion described in the publication is inferior in storage stability due to the presence of a large amount of epoxy groups even after modification with a polyoxyalkyleneamine compound. Furthermore, the molecular weight of the epoxy resin itself is small, and lacquer drying has insufficient substrate adhesion, and the hardness is not sufficiently developed.

Japanese Patent Laid-Open No. 10-183055

  The problem to be solved by the present invention is to provide an aqueous resin composition which is excellent in substrate adhesion and hardness of a coating film and excellent in storage stability.

  As a result of intensive studies to solve the above problems, the present inventor has a molecular structure obtained by reacting a bisphenol type epoxy resin and a polyoxyalkyleneamine as a main skeleton, and a hard segment in the polymer structure. By introducing a urethane bond and further adjusting the weight average molecular weight of the whole polymer to the range of 10,000 to 100,000, adhesion to the substrate, coating film hardness, and further storage stability as an aqueous resin dispersion As a result, the present invention has been completed.

  That is, the present invention provides an aqueous resin composition comprising an aqueous resin (A) and an aqueous medium (B) as essential components, wherein the aqueous resin (A) reacts a bisphenol-type epoxy resin with a polyoxyalkyleneamine. Having a molecular structure, a urethane bond and a carboxyl group in the polymer structure, and the water-based resin (A) has a weight average molecular weight in the range of 10,000 to 100,000. It is related with the water-based resin composition characterized by these.

  ADVANTAGE OF THE INVENTION According to this invention, the aqueous resin composition which is excellent in the base-material adhesiveness of a coating film and coating-film hardness, and is excellent in storage stability can be provided.

  Therefore, the aqueous resin composition of the present invention 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 aqueous resin (A) used in the present invention has a polymer structure whose main structure is a molecular structure obtained by reacting a bisphenol type epoxy resin and a polyoxyalkyleneamine, and a urethane bond and a carboxyl group in the polymer structure. And the weight average molecular weight of the aqueous resin (A) is in the range of 10,000 to 100,000.

  Here, when the weight average molecular weight of the aqueous resin (A) is less than 10,000, stability to the aqueous medium (B) is impaired, storage stability is lowered, and coating film hardness is low. . On the other hand, when it is larger than 100,000, the synthesis control becomes difficult. From the viewpoint of excellent balance, the weight average molecular weight of the aqueous resin (A) is preferably in the range of 25,000 to 50,000.

Here, the weight average molecular weight is a value obtained by GPC measurement, and can be measured under the following conditions.
[GPC measurement conditions]
Measuring device: “HLC-8220 GPC” manufactured by Tosoh Corporation
Column: Guard column “H _XL -L” manufactured by Tosoh Corporation
+ "TSK-GEL G2000HXL" manufactured by Tosoh Corporation
+ "TSK-GEL G2000HXL" manufactured by Tosoh Corporation
+ Tosoh Corporation “TSK-GEL G3000HXL”
+ Tosoh Corporation “TSK-GEL G4000HXL”
Detector: RI (Differential refraction diameter)
Data processing: “GPC-8020 Model II version 4.10” manufactured by Tosoh Corporation
Measurement conditions: Column temperature 40 ° C
Developing solvent Tetrahydrofuran
Flow rate 1.0ml / min

  Standard: The following monodisperse polystyrene having a known molecular weight was used in accordance with the measurement manual of “GPC-8020 Model II version 4.10”.

(Polystyrene used)
“A-500” manufactured by Tosoh Corporation
"A-1000" manufactured by Tosoh Corporation
"A-2500" manufactured by Tosoh Corporation
"A-5000" manufactured by Tosoh Corporation
“F-1” manufactured by Tosoh Corporation
"F-2" manufactured by Tosoh Corporation
“F-4” manufactured by Tosoh Corporation
“F-10” manufactured by Tosoh Corporation
“F-20” manufactured by Tosoh Corporation
“F-40” manufactured by Tosoh Corporation
“F-80” manufactured by Tosoh Corporation
“F-128” manufactured by Tosoh Corporation
Sample: 1 g of trifluoroacetic anhydride added to 0.5 g of resin solids, treated in a sealed stopper at 80 ° C. for 1 hour, then opened and further treated at 80 ° C. for 1 hour, diluted to 10 ml of THF.

  The aqueous resin (A) has a polymer structure having a molecular structure obtained by reacting a bisphenol type epoxy resin and polyoxyalkyleneamine as a main skeleton, and urethane bonds and carboxyls are contained in the polymer structure. And having a group. In the present invention, since it has a soft segment attributed to polyoxyalkyleneamine and a hard segment attributed to the urethane bond, it exhibits excellent dispersibility and storage stability in the aqueous medium (B). The coating film hardness after work can be increased. Moreover, since it has a carboxyl group in the molecular structure, it has both a nonionic hydrophilic group derived from polyoxyalkylene and an anionic hydrophilic group derived from the carboxyl group, and the aqueous resin (A ) Can be dramatically improved in storage stability.

As a method for introducing a molecular structure obtained by reacting a bisphenol-type epoxy resin and a polyoxyalkyleneamine into a polymer structure of the aqueous resin (A), a urethane bond and a carboxyl group, specifically,
(I) bisphenol type epoxy resin,
(Ii) polyoxyalkyleneamine,
(Iii) a reaction product of a polyvalent isocyanate compound and an alkylene glycol, and
(Iv) A method of reacting (meth) acrylic acid as an essential component can be mentioned.

The bisphenol type epoxy resin (i) used here is, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AD type epoxy resin, biscresol F type epoxy resin, bisphenol S type epoxy resin, bisphenol Z type epoxy. Examples thereof include bisphenol-type epoxy resins such as resins, and aromatic nuclei of these epoxy resins substituted with a methylene group, an ethylene group, a bromine atom, and a chlorine atom.
Among these, bisphenol A type epoxy resins are preferred because of the coating film properties of the aqueous dispersion obtained. Further, the epoxy equivalent of the bisphenol type epoxy resin (i) is preferably 180 to 4,000 g / eq, and particularly preferably 300 to 3,000 g / eq from the viewpoint of coating film hardness and coating property. Here, the epoxy equivalent of the bisphenol-type epoxy resin (i) is a value measured according to “JIS K7236 (2001)”.

  Next, as the polyoxyalkyleneamine (ii), ethylene oxide structural unit, alkylene oxide structural unit such as 1,2-propyleneoxy structural unit 1,3-propyleneoxy structural unit in the molecular structure is a repeating unit, Examples thereof include compounds having an amino group at one or both ends of the molecular structure.

  Here, the number of repeating units of the alkylene oxide structural unit is preferably 10 to 100 on average from the viewpoint of the water dispersibility of the resin particles, and the base material adhesion of the coating film, the coating film hardness, and the aqueous resin dispersion From the viewpoint of the balance with the storage stability, it is preferably 13 to 90, particularly preferably 15 to 75.

  Further, when the active hydrogen equivalent of the polyoxyalkyleneamine is 400 g / eq or more, the stability of the resin particles in the aqueous medium (B) becomes good, and when it is 2000 g / eq or less, crystallization of the resin particles can be prevented. it can. Therefore, the active hydrogen equivalent is preferably in the range of 400 to 2000 g / eq.

  Specifically, such polyoxyalkyleneamine (ii) has the following structural formulas (1) to (3).

(In the formula, R ¹ is a hydrogen atom, a methyl group, an ethyl group, a propyl group, or a t-butyl group, and R ² is an ethylene group, 1,2-propylene group, 2,3-propylene group, 1,3. A propylene group, R ³ is a methylene group, an ethylene group, a 1,2-propylene group, a 2,3-propylene group, a 1,3-propylene group, and n is an average of 10 to 100 repeating units. .)

(Wherein R ⁴ is a methylene group, ethylene group, 1,2-propylene group, 2,3-propylene group, 1,3-propylene group, R ² is an ethylene group, 1,2-propylene group, 2 , 3-propylene group, 1,3-propylene group, R ³ is a methylene group, ethylene group, 1,2-propylene group, 2,3-propylene group, 1,3-propylene group, and n is repeating (The average unit is 10 to 100.)

(In the formula, R ² is independently an ethylene group, 1,2-propylene group, 2,3-propylene group, 1,3-propylene group, and R ⁵ is a hydrogen atom, a methyl group, or an ethyl group. , P is an average of 0 to 5 repeating units, and x, y, and z are 1 to 10 on an average of repeating units, respectively.
Is particularly preferred from the viewpoint that the stability of the resin particles in an aqueous medium is improved.

  In the structural formulas (1) to (3), the following structural formula

The polyoxyalkylene moiety represented by the repeating unit is selected from the group consisting of an oxyethylene group, an oxy-1,2-propylene group, an oxy-2,3-propylene group, and an oxy-1,3-propylene group. Or a polyoxyalkylene structure in which two or more types are randomly bonded, or a polyoxyalkylene structure in which two or more types are bonded in a block shape. Also good.

  Among these, monoamines represented by the structural formula (1) are preferable from the viewpoint of excellent reactivity with a bisphenol type epoxy resin and stability of the product. In the structural formula (1) or (2), the value of n is particularly preferably 13 to 90, and particularly preferably 15 to 75.

  Next, the reaction product (iii) of the polyvalent isocyanate compound and alkylene glycol used in the present invention is a urethane bond-containing compound obtained by reacting one molecule of the polyvalent isocyanate compound and alkylene glycol with the latter, Or the oligomer obtained by making a polyvalent isocyanate compound and alkylene glycol react is mentioned. Among these, the latter oligomer is particularly preferable from the viewpoint that the effect of improving the hardness of the coating film due to the hard segment formation becomes remarkable. Moreover, it is preferable from the point of reactivity with another raw material component to make it react so that an isocyanate group may remain | survive at the molecular terminal.

  Specifically, the polyvalent isocyanate compound used here is 2,4-tolylene diisocyanate or 2,6-tolylene diisocyanate, m- or p-phenylene diisocyanate, p-xylene diisocyanate, ethylene diisocyanate, tetramethylene- 1,4-diisocyanate, hexamethylene-1,6-diisocyanate, 3,3′-dichloro-4,4′-biphenylene diisocyanate, 4,4′-biphenylene diisocyanate or 1,5-naphthalene diisocyanate, tolidine diisocyanate, Examples include solon diisocyanate, cyclohexane diisocyanate, toluidine diisocyanate, and diphenylmethane diisocyanate, and triphenylmethane triisocyanate. Among these, 2,4-tolylene diisocyanate or 2,6-tolylene diisocyanate is preferable from the viewpoint of good hardness after the coating film is formed.

  On the other hand, examples of the alkylene glycol to be reacted with the polyvalent isocyanate compound include ethylene glycol, propylene glycol, tetramethylene glycol, and diethylene glycol. Among these, ethylene glycol is particularly preferred in the present invention from the viewpoint of the hardness of the cured coating film.

  The (meth) acrylic acid (iv) is acrylic acid or methacrylic acid. In the present invention, a carboxyl group which is a nonionic hydrophilic group is introduced into the molecular structure of the aqueous resin (A) by the Michael addition reaction of the (meth) acrylic acid (iv) with the amino group in the reaction solution. Thus, the finally obtained aqueous resin (A) has both nonionic / anionic hydrophilic groups, and the dispersibility stability in the aqueous medium (B) has been greatly improved. It will exhibit storage stability.

Above,
(I) bisphenol type epoxy resin,
(Ii) polyoxyalkyleneamine,
(Iii) a reaction product of a polyvalent isocyanate compound and an alkylene glycol, and
(Iv) As a method of reacting (meth) acrylic acid, these may be reacted at once, or the components (i) to (iv) may be reacted in multiple stages. In the latter case, the reactions may be performed in any order, for example
Method 1: Method of reacting bisphenol type epoxy resin (i) and polyoxyalkyleneamine (ii), reacting the reaction product (iii) with this, and then reacting with (meth) acrylic acid (iv) ,
Method 2: A polyoxyalkyleneamine (ii) and the reaction product (iii) are reacted to obtain a polyurethane (a) having a polyoxyalkyleneamino group at the terminal, while the bisphenol type epoxy resin (i) and poly Reacting with oxyalkyleneamine (ii) to produce a polyoxyalkylene group-containing epoxy resin (b);
Bisphenol type epoxy resin (i),
Polyurethane having a polyoxyalkyleneamino group at the terminal (a), and
Reacting the polyoxyalkylene group-containing epoxy resin (b);
A method of reacting (meth) acrylic acid (iv);
Etc.

  Among these, in the present invention, Method 2 is preferable because the obtained polymer has a high molecular weight and is excellent in storage stability.

  The reaction between the bisphenol type epoxy resin (i) and the polyoxyalkyleneamine (ii) can be carried out without solvent or in the presence of a solvent. Here, the solvent is preferably a hydrophilic solvent because it does not require desolvation after the reaction. Specifically, cellosolves, propylene glycols and glymes are preferable, and propyl cellosolve, butyl cellosolve, t -Butyl cellosolve, methoxypropanol, propoxypropanol. The reaction temperature is preferably in the range of 60 to 120 ° C. from the viewpoint of good reactivity.

  As a method for producing a polyurethane (a) having a polyoxyalkyleneamino group at the terminal by reacting the polyoxyalkyleneamine (ii) with the reaction product (iii), specifically, polyoxyalkylene The reaction can be carried out in the presence of the amine (ii), the reaction product (iii), and, if necessary, the bisphenol type epoxy resin (i) in the absence of a solvent or in the presence of a solvent. Here, it is preferable to use a hydrophilic solvent as the solvent, since desolvation after the reaction is unnecessary, specifically, cellosolves, propylene glycols, and glymes are preferable, and more preferably propyl cellosolve, butyl cellosolve, Examples thereof include t-butyl cellosolve, methoxypropanol, and propoxypropanol. The reaction temperature is preferably in the range of 60 to 120 ° C. from the viewpoint of excellent reactivity.

  Under the present circumstances, the reaction ratio of each component is 0.01-5 mass% in all the raw material components which use ratio of the polyvalent isocyanate compound which uses the said reaction product (iii) as a raw material comprises aqueous resin (A). It is preferable to use it so that it may become 0.1-1 mass%, preferably from the point of coating-film hardness and the storage stability of a coating material.

  Furthermore, the method of reacting the bisphenol-type epoxy resin (i), the polyurethane (a) having a polyoxyalkylene amino group at the terminal, and the polyoxyalkylene group-containing epoxy resin (b) is specifically the above-described hydrophilicity. In the presence of a solvent, the bisphenol-type epoxy resin (i), the polyurethane (a) having a polyoxyalkyleneamino group at the terminal, and the polyoxyalkylene group-containing epoxy resin (b) are heated from 60 to 120 ° C. The method of making it react is mentioned.

  Here, as described above, the reaction ratio of each component is such that the use ratio of the polyvalent isocyanate compound in all the raw material components (including the amine compound described later) constituting the aqueous resin (A) is 0.01 to 5. It is used so that it may become the range of the mass%, and polyoxyalkyleneamine (ii) is used in the ratio which will be 5-15 mass% in all the raw material components of coating-film hardness and the storage stability of a coating material. It is preferable from the point. In the present invention, since an anionic hydrophilic group derived from (meth) acrylic acid (iv) is introduced into the aqueous resin (A), the amount of polyoxyalkyleneamine (ii) used can be relatively reduced. The invention dramatically improves the storage stability of the aqueous resin composition.

  Next, the method of reacting the reaction product thus obtained with (meth) acrylic acid (iv) is specifically a Michael addition reaction immediately after the above reaction under a temperature condition of 60 to 120 ° C. Alternatively, after the terminal epoxy group in the reaction product is reacted with an amine compound, the reaction product and (meth) acrylic acid (iv) are subjected to a temperature condition of 60 to 120 ° C. A Michael addition reaction method may be used. The latter method is preferred because the aqueous dispersion of the present invention is excellent in adhesion to a substrate as a coating material.

  Examples of the amine compound used here include primary alkylamines such as butylamine, octylamine, oleylamine and 2-ethylhexylamine, primary alkanolamines such as monoethanolamine, 2-ethoxyethanolamine and 2-hydroxypropanolamine, and diethylenetriamine. , Aliphatic polyamines such as triethylenetetramine, tetraethylenepentamine, m-xylenediamine and p-xylenediamine, alicyclic polyamines such as 1,3-diaminocyclohexane and isophoronediamine, polyamines and aldehyde compounds and 1 Mannich bases composed of polycondensates with polyvalent or polyhydric phenols, aromatic polyamines such as diaminodiphenylmethane, polyamines obtained by reacting polyamines with polycarboxylic acids and dimer acids De polyamines, and the like. Primary alkylamines and primary alkanolamines are preferred from the viewpoint of excellent storage stability when formed into resin particles.

  The reaction between the aqueous resin and the amine compound can be performed by a known method in the presence of a useless solvent. A known solvent can be used as the solvent, but it is preferable to use a hydrophilic solvent because it does not require desolvation after the reaction. The hydrophilic solvent is preferably cellosolves, propylene glycols or glymes, more preferably propyl cellosolve, butyl cellosolve, t-butyl cellosolve, methoxypropanol or propoxypropanol.

  The reaction ratio between the aqueous resin and the amine compound is such that the active hydrogen equivalent of the amine compound is larger than the epoxy equivalent of the aqueous resin from the storage stability of the aqueous resin (A) obtained. Is preferred.

  The reaction between the aqueous resin and (meth) acrylic acid (iv) can be carried out by a known method in the presence of an unnecessary agent and a solvent. A known solvent can be used as the solvent, but it is preferable to use a hydrophilic solvent because it does not require desolvation after the reaction. The hydrophilic solvent is preferably cellosolves, propylene glycols or glymes, more preferably propyl cellosolve, butyl cellosolve, t-butyl cellosolve, methoxypropanol or propoxypropanol.

  The reaction ratio between the aqueous resin and (meth) acrylic acid (iv) is (meth) acrylic acid (iv) because the effect of improving the storage stability of the aqueous resin (A) obtained is remarkable. Is preferably reacted at a ratio of 0.5 to 5% by mass in all raw material components.

  The aqueous resin (A) thus obtained is then subjected to dropwise addition of the aqueous medium (B) to the reaction product to obtain the intended aqueous resin composition.

  Here, examples of the aqueous medium (B) include water, distilled water, ion-exchanged water, and a solution in which a lower alcohol is dissolved therein. In the present invention, water, distilled water, or ion-exchanged water is an environment. From the viewpoint of problems and the dispersibility of the aqueous resin (A), distilled water or ion-exchanged water is particularly preferable.

  Here, as a dropping method of the aqueous medium (B), for example, it can be carried out by continuous dropping or divided addition, and the temperature of the aqueous medium (B) can be 10 to 90 ° C. The temperature of the aqueous medium (B) is more preferably 20 to 80 ° C. in order to maintain uniform mixing of the resin components.

  The aqueous resin composition thus obtained is excellent in storage stability when the resin particles dispersed in the aqueous medium (B) are aqueous resin dispersions having an average particle diameter in the range of 0.01 to 10 μm. To preferred.

  In the present invention, for the purpose of enhancing the water solubility of the aqueous resin (A), it is desirable to use a compound having a quaternary onium moiety in the aqueous resin (A). As a compound which has a quaternary onium part which can be used here, what is represented by following Structural formula (4) or (5) is mentioned, for example.

(In the formula, n is an average of 1 to 5 repeating units of a methylene group.)

  The water-based resin composition of the present invention may be used in combination with other resin components such as other polyester-based water-based resins and acrylic water-based resins, as long as the characteristics of the present invention are not impaired.

  In addition, the aqueous resin composition of the present invention may contain various additives such as repellency inhibitors, anti-sagging agents, spreading agents, antifoaming agents, curing accelerators, ultraviolet absorbers, and light stabilizers as necessary. You may mix | blend.

  Although it does not restrict | limit especially as a use of the aqueous 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 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 mass parts with respect to a total of 100 mass parts of aqueous resin composition and the hardening | curing agent mix | blended as needed, such as coating-film performance, coating workability, etc. It is preferable from the point.

  The coating method when the aqueous resin composition of the present invention is used for coating is not particularly limited, and can be performed by roll coating, spraying, brushing, spatula, bar coater, dip coating, or electrodeposition coating. 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 using the aqueous resin composition of the present invention as an adhesive, it is not particularly limited, and can be performed by matching the adhesive surface of the substrate after application to the substrate with spray, brush, spatula, The bonding portion can form a strong adhesive layer by fixing the surrounding area or pressure bonding. 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.

  In addition, when the aqueous resin composition of the present invention is used as a fiber sizing agent, it can be carried out without any particular limitation. For example, after applying to a fiber immediately after spinning using a roller coater and winding it as a fiber strand And a method of drying. 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 mass as the resin solid content with respect to the fiber.

  Moreover, when using the aqueous 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 mass unless otherwise specified, and the measurement conditions of epoxy equivalent and weight average molecular weight are as follows.
[Epoxy equivalent]
It measured based on "JIS K7236 (2001)".
[Measurement Conditions for Weight Average Molecular Weight (Measurement Conditions for GPC)]
Measuring device: “HLC-8220 GPC” manufactured by Tosoh Corporation
Column: Guard column “H _XL -L” manufactured by Tosoh Corporation
+ "TSK-GEL G2000HXL" manufactured by Tosoh Corporation
+ "TSK-GEL G2000HXL" manufactured by Tosoh Corporation
+ Tosoh Corporation “TSK-GEL G3000HXL”
+ Tosoh Corporation “TSK-GEL G4000HXL”
Detector: RI (Differential refraction diameter)
Data processing: “GPC-8020 Model II version 4.10” manufactured by Tosoh Corporation
Measurement conditions: Column temperature 40 ° C
Developing solvent Tetrahydrofuran
Flow rate: 1.0 ml / min Standard: The following monodisperse polystyrene having a known molecular weight was used in accordance with the measurement manual of “GPC-8020 Model II version 4.10”.

(Polystyrene used)
“A-500” manufactured by Tosoh Corporation
"A-1000" manufactured by Tosoh Corporation
"A-2500" manufactured by Tosoh Corporation
"A-5000" manufactured by Tosoh Corporation
“F-1” manufactured by Tosoh Corporation
"F-2" manufactured by Tosoh Corporation
“F-4” manufactured by Tosoh Corporation
“F-10” manufactured by Tosoh Corporation
“F-20” manufactured by Tosoh Corporation
“F-40” manufactured by Tosoh Corporation
“F-80” manufactured by Tosoh Corporation
“F-128” manufactured by Tosoh Corporation
Sample: 1 g of trifluoroacetic anhydride was added to 0.5 g of resin solid content, treated in an airtight stopper at 80 ° C. for 1 hour, then opened and further treated at 80 ° C. for 1 hour, diluted to 10 ml of THF to obtain a measurement sample. .

Synthesis Example 1 (Intermediate: Synthesis of bisphenol type epoxy resin solution)
In a four-necked flask equipped with a thermometer, a stirrer, and a nitrogen gas inlet tube, 300 parts of bisphenol A type epoxy resin (“Epicron 850” manufactured by Dainippon Ink & Chemicals, Inc.) with an epoxy equivalent of 188 g / eq, .9 parts were charged and heated at 80 ° C. for homogenization. To this, 0.1 part of tetramethylammonium chloride (50% aqueous solution) was added and stirred at 140 ° C. for 3 hours. Thereafter, 129.3 parts of butyl cellosolve was added and the sales were made uniform to obtain an epoxy resin solution having an epoxy equivalent of 480 g / eq and a nonvolatile content of 75%. This is defined as (A-1).

Synthesis Example 2 (Synthesis of aqueous resin intermediate)
Into a four-necked flask equipped with a thermometer, a stirrer, and a nitrogen gas introduction tube, 188 parts of bisphenol A type epoxy resin having an epoxy equivalent of 188 g / eq and tolylene diisocyanate ("Cosmonate" manufactured by Takeda Chemical Co., Ltd.) T-80 ") 17.4 parts are charged. Next, the temperature is raised to 50 ° C., 1.55 parts of ethylene glycol is charged, and the mixture is reacted at 80 ° C. for 2 hours. Next, while cooling, 722 parts of polyoxypropyleneamine (“Jeffamine M-1000” active hydrogen equivalent 505 g / equivalent by Huntsman) is charged. Then, it stirred at 100 degreeC for 5 hours. A resin having a nonvolatile content of 70% was obtained by adding 398 parts of butyl cellosolve and stirring uniformly. This is defined as (A-2).

Synthesis Example 3 (Synthesis of aqueous resin intermediate)
Into a four-necked flask equipped with a thermometer, a stirrer, and a nitrogen gas introduction tube, 188 parts of bisphenol A type epoxy resin having an epoxy equivalent of 188 g / eq and tolylene diisocyanate ("Cosmonate" manufactured by Takeda Chemical Co., Ltd.) T-80 ") 34.8 parts are charged. Next, the temperature is raised to 50 ° C., 3.1 parts of ethylene glycol is charged, and the mixture is reacted at 80 ° C. for 2 hours. Next, 808 parts of polyoxypropyleneamine (“Jeffamine M-1000” active hydrogen equivalent 505 g / equivalent) manufactured by Huntsman Co., Ltd.) is charged while cooling. Then, it stirred at 100 degreeC for 5 hours. By adding 443.1 parts of butyl cellosolve and stirring uniformly, a resin having a nonvolatile content of 70% was obtained. This is defined as (A-3).

Synthesis example 4 (aqueous resin composition)
A four-necked flask equipped with a thermometer, a stirrer, and a nitrogen gas inlet tube is charged with 640 parts of a bisphenol type epoxy resin solution (A-1) and heated to 90 ° C. Next, 71,2 parts of an aqueous resin intermediate (A-2) was charged and stirred at 100 ° C. for 2 hours. Next, 97.6 parts of butyl cellosolve was charged, 36.6 parts of monoethanolamine was added at 70 ° C., and the mixture was stirred at 100 ° C. for 3 hours. Thereafter, 15.5 parts of acrylic acid is added and reacted at 100 ° C. for 2 hours. Cooling was started, and 850.6 parts of ion exchange water was added dropwise over 4 hours. The liquid temperature at the time of dripping water was managed at 40-50 degreeC. Next, 25.7 parts of a styrenated phenol emulsifier (Daiichi Kogyo Co., Ltd., Neugen EA-207D) was added and stirred uniformly to obtain an aqueous resin composition having a nonvolatile content of 34%. This is defined as (B-1).

Synthesis Example 5 (aqueous resin composition)
A four-necked flask equipped with a thermometer stirrer and a nitrogen gas inlet tube is charged with 640 parts of a bisphenol type epoxy resin solution (A-1) and heated to 90 ° C. Next, 118.6 parts of aqueous resin intermediate (A-2) was charged and stirred at 100 ° C. for 2 hours. Next, 99.7 parts of butyl cellosolve was charged, 36.6 parts of monoethanolamine was added at 70 ° C., and the mixture was stirred at 100 ° C. for 3 hours. Thereafter, 5.0 parts of acrylic acid is added and reacted at 100 ° C. for 2 hours. Cooling was started, and 878.3 parts of ion-exchanged water was added dropwise over 4 hours. The liquid temperature at the time of dripping water was managed at 40-50 degreeC. Next, 27.0 parts of a styrenated phenol emulsifier ("Neugen EA-197D" manufactured by Daiichi Kogyo Co., Ltd.) was added and stirred uniformly to obtain an aqueous resin composition having a nonvolatile content of 34%. This is defined as (B-2).

Synthesis Example 6 (aqueous resin composition)
A four-necked flask equipped with a thermometer, a stirrer, and a nitrogen gas inlet tube is charged with 640 parts of a bisphenol type epoxy resin solution (A-1) and heated to 90 ° C. Next, 123.1 parts of aqueous resin intermediate (A-3) was charged and stirred at 100 ° C. for 2 hours. Next, 100 parts of butyl cellosolve was charged, 36.6 parts of monoethanolamine was added at 70 ° C., and the mixture was stirred at 100 ° C. for 3 hours. Thereafter, 4.9 parts of acrylic acid is added and reacted at 100 ° C. for 2 hours. Cooling was started and 882.8 parts of ion-exchanged water was added dropwise over 4 hours. The liquid temperature at the time of dripping water was managed at 40-50 degreeC. Next, 26.8 parts of a styrenated phenol emulsifier ("Neugen EA-207D" manufactured by Daiichi Kogyo Co., Ltd.) was added and stirred uniformly to obtain an aqueous resin composition having a nonvolatile content of 34%. This is defined as (B-3).

Comparative Synthesis Example 1 (Synthesis Example 1 of JP-A-10-183055)
A four-necked flask equipped with a thermometer, a stirrer, and a nitrogen gas inlet tube was charged with 740 parts of a solid bisphenol A type epoxy resin (“Epicron 1050” manufactured by Dainippon Ink and Chemicals, epoxy equivalent 475 g / eq), 100 Homogenized at 0 ° C. To this, 10 parts of monoethanolamine, 250 parts of polyoxypropyleneamine “Jefamine M-1000” and 333 parts of butyl cellosolve were added and stirred at 130 ° C. for 7 hours. After cooling to 100 ° C. or lower, 666 parts of ion-exchanged water was added and stirred uniformly to obtain an aqueous resin composition having a nonvolatile content of 45% by mass. This non-volatile resin is defined as (C-1).

  Table 1 shows the properties of the resins obtained in Synthesis Examples 1 to 9 and Comparative Synthesis Example 1.

  The average particle size was measured using a Nikiso Co., Ltd. grain size measuring device “Micro Trac UPA-150”. For Comparative Example 2, an aqueous resin composition could not be obtained.

Table 1 shows the properties of the resins obtained in Synthesis Examples 1 to 6 and Comparative Synthesis Example 1.
The average particle size was measured using a Nikiso Co., Ltd. grain size measuring device “Micro Trac UPA-150”.

（表１中、「ＶＯＣ」は、各ワニス中に存在する揮発性溶剤の含有率である。）

(In Table 1, “VOC” is the content of the volatile solvent present in each varnish.)

Examples 1 to 3 and Comparative Example 1
Next, an aqueous coating material is prepared using the obtained aqueous resin dispersion at a blending ratio shown in Table 2, and a dull steel plate whose surface is degreased with xylene is made to have a dry film thickness of 15 μm with a bar coater. After coating, the physical properties of the coating film were evaluated. In addition, the physical property of the coating film of Table 2 is a test result after performing 25 degreeC x 5-day curing after drying at 100 degreeC x 20 minutes. In addition, as for the water resistance, as a result of being immersed in a 40 ° C. water bath for 7 and a half days, as for alkali resistance, as a result of being immersed in a 5% aqueous sodium hydroxide solution at 25 ° C. The result after 300 hours.
Moreover, each test method and evaluation criteria which confirmed the presence or absence of isolation | separation in an external appearance by putting the obtained dispersion into a 50 degreeC dryer are as follows.

Tackiness: The tackiness of the coating film surface was determined by touch.
○: No tack, ×: Tack

Scratch hardness (pencil method): Measured according to JIS K-5600-5-4 using Mitsubishi Uni.
Cross cut test: According to JIS K-5600-5-6 (1999), cuts were made at intervals of 1 mm, and the state of the coating film was visually observed after peeling off after applying the tape.
○: No peeling. X: Peeling is seen.

Flexibility: In accordance with JIS K-5600-5-1 (1999), the coating film was observed to be cracked and peeled off from the substrate when bent by a cylindrical mandrel (diameter 2 mm).
○: No cracking or peeling occurred. X: Cracking or peeling occurred.
Water resistance: Performed according to JIS K-5600-2 (1999).

Salt spray test The surface of the paint film was scratched and a 5% NaCl aqueous solution was sprayed continuously at 35 ° C for 1000 hours. It was confirmed. Unit (mm)
(Coating state)
○: No change. ×: Whitening

Storage stability Appearance change at 50 ° C. was confirmed.

表２中の略号は以下の通りである。また、「イオン交換水」は、各ワニスに追加されたイオン交換水の質量部である。
「ＣＲ−９７」 ：石原産業製、酸化チタン「ＴＩＰＡＱＵＥ ＣＲ−９５」
「Ｂ−１５００」 ：白石カルシウム株式会社製、炭酸カルシウム「Ｂ−１５００」
「Ｋ−１０５」 ：テイカ株式会社製、防錆顔料「Ｋ−ホワイト Ｋ−１０５」
「ＭＡ−１」 ：三菱化学製、カーボンブラック「ＭＡ−１」

Abbreviations in Table 2 are as follows. Further, “ion exchange water” is a mass part of ion exchange water added to each varnish.
"CR-97": Ishihara Sangyo, titanium oxide "TIPAQUE CR-95"
“B-1500”: manufactured by Shiraishi Calcium Co., Ltd., calcium carbonate “B-1500”
“K-105”: Anti-corrosion pigment “K-White K-105” manufactured by Teika Co., Ltd.
“MA-1”: Carbon black “MA-1” manufactured by Mitsubishi Chemical

Claims (8)

A water-based resin composition comprising an aqueous resin (A) and an aqueous medium (B) as essential components, wherein the aqueous resin (A) is obtained by reacting a bisphenol-type epoxy resin and a polyoxyalkyleneamine. And a urethane bond and a carboxyl group in the polymer structure, and the aqueous resin (A) has a weight average molecular weight in the range of 10,000 to 100,000. Resin composition. The aqueous resin (A) is
(I) bisphenol type epoxy resin,
(Ii) polyoxyalkyleneamine,
The aqueous resin composition according to claim 1, which is obtained by reacting (iii) a reaction product of a polyvalent isocyanate compound and an alkylene glycol, and (iv) (meth) acrylic acid as essential components. The component (iii), which is a raw material of the aqueous resin (A), is obtained by reacting a polyvalent isocyanate compound and an alkylene glycol, and the use ratio of the polyvalent isocyanate compound is 0 in all raw material components. The aqueous resin composition according to claim 2, which is in a range of 0.01 to 5% by mass. The aqueous resin composition according to claim 2, wherein the aqueous resin (A) is obtained using polyoxyalkyleneamine (ii) in a ratio of 5 to 15% by mass in all raw material components. 5. The aqueous resin composition according to claim 1, wherein the polyoxyalkyleneamine which is a raw material of the aqueous resin (A) is in the range of an active hydrogen equivalent of 400 to 2,000 g / equivalent. . The aqueous resin (A) is obtained by using (meth) acrylic acid (iv) in a ratio of 0.5 to 5% by mass in all raw material components. The water-based resin composition described in 1. The aqueous resin composition according to any one of claims 1 to 6, wherein the aqueous resin (A) is dispersed as resin particles having an average particle diameter of 0.01 to 10 µm in the aqueous medium (B). . The aqueous resin composition according to any one of claims 1 to 7, wherein a non-volatile content is 10 to 60% by mass.