JP2008222771A - Water-based resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a water-based resin composition capable of giving a coating film excellent in adhesion to substrates and hardness and being excellent in storage stability. <P>SOLUTION: The water-based resin composition is a water-based resin composition consisting of an aqueous medium and core/shell resin particles dispersed therein, wherein the resin component (A) which constitutes the core of each resin particles is (a) a bisphenol A derived epoxy resin of an epoxy equivalent of 400-4,000 g/eq or an amine-modified product thereof, and the resin component (B) which constitutes the shell of each resin particle is (b) a resin of a weight-average molecular weight of 3,000-10,000 obtained by reacting a polyoxyalkyleneamine (composed of 10-100, on the average, oxyalkylene units) with a bisphenol-derived epoxy resin. <P>COPYRIGHT: (C)2008,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 the lacquer drying has insufficient adhesion to the substrate, 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 that is excellent in the adhesion of the coating film to the substrate and the hardness of the coating film, and is excellent in storage stability.

  As a result of intensive studies to solve the above problems, the present inventor has a polyoxyalkylene group, but exists only in the shell part of the core-shell structure. Even if the number is small, excellent coating film hardness can be expressed. Since the molecular weight of the core part and the shell part is large, it has been found that the coating film hardness is good, and the present invention has been completed.

  That is, the present invention is an aqueous resin composition in which core-shell resin particles are dispersed in an aqueous medium, and the resin component (A) forming the core portion of the resin particles has an epoxy equivalent of 400-4. 2,000 g / equivalent bisphenol-type epoxy resin or amine-modified product thereof (a), wherein the resin component (B) forming the shell part of the resin particles reacts polyoxyalkyleneamine with a bifunctional epoxy resin. An aqueous resin composition characterized by being a resin (b) having a weight average molecular weight of 3,000 to 10,000 obtained.

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 resin component (A) which forms the core part used in the present invention is a bisphenol type epoxy resin having an epoxy equivalent of 400 to 4,000 g / equivalent or its amine-modified product (a).

  The epoxy equivalent 400-4000 g / equivalent bisphenol type epoxy resin (a) may be an epoxy resin having a phenoxy skeleton derived from the bisphenol skeleton in the main skeleton, 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 resin, those obtained by substituting a methylene group, an ethylene group, a bromine atom and a chlorine atom for the aromatic nucleus of these epoxy resins; Furthermore, aliphatic alcohols such as the above bisphenol type epoxy resin and t-butylcatechol, butanol, aliphatic alcohols having 11 to 12 carbon atoms, phenol, p-ethylphenol, o-cresol, m-cresol, p-cresol, -Aliphatic alcohols such as tertiary butylphenol, s-butylphenol, nonylphenol, xylenol, phenol novolac resin, cresol novolac resin, p-tert-butylphenol novolac resin, nonylphenol novolac resin, t-butylcatechol, butanol, and 11 to 12 carbon atoms A copolymer with a hydroxyl group-containing compound such as aliphatic alcohol, phenol, p-ethylphenol, o-cresol, m-cresol, p-cresol, p-tertiarybutylphenol, s-butylphenol, nonylphenol; and bisphenol A Bisphenols such as bisphenol F, bisphenol AD, biscresol F, bisphenol S, bisphenol Z, the hydroxyl group-containing compounds, and epihalo Reacting a phosphorus include epoxy resins obtained.

  The bisphenol type epoxy resin (a) includes, in addition to the above-mentioned resins, a phenol novolak type epoxy resin, a cresol novolak type epoxy resin, a p-tert-butylphenol novolak type epoxy resin, a nonylphenol novolak type epoxy resin, t A polyvalent epoxy resin such as a butylcatechol type epoxy resin, an aliphatic alcohol such as butanol, an aliphatic alcohol having 11 to 12 carbon atoms, phenol, p-ethylphenol, o-cresol, m-cresol, p-cresol, Contains epoxy groups such as condensates of monovalent phenols such as p-tertiarybutylphenol, s-butylphenol, nonylphenol, xylenol and epihalohydrin, and condensates of monovalent carboxylic acids such as neodecanoic acid and epihalohydrin. Compound, bisphenol A, bisphenol F, bisphenol AD, biscresol F, bisphenol S, and epoxy resins obtained by a bisphenol by reaction of bisphenol Z and the like.

  Among these, bisphenol A type epoxy resins and bisphenol F type epoxy resins are preferable because they have excellent coating film properties when used as paints.

  The epoxy equivalent of the bisphenol type epoxy resin is preferably 400 to 4,000 g / eq. When it is less than 400 g / eq, the coating film at the time of drying is hard and the flexibility is impaired, and when it is more than 4,000 g / eq, a large amount of a hydrophilic solvent is required as a cosolvent, which affects the drying property. Here, the epoxy equivalent of the bisphenol-type epoxy resin is a value measured according to “JIS K7236 (2001)”.

  In the resin component (A), the amine-modified product (a) of bisphenol type epoxy resin having an epoxy equivalent of 400 to 4,000 g / equivalent is the bisphenol type epoxy resin having an epoxy equivalent of 400 to 4,000 g / eq, It is an epoxy resin in which an amine compound skeleton is introduced into a molecular main chain or at a molecular end by reacting with an amine compound having reactivity with an epoxy group.

  The amine compound is not particularly limited as long as it is a compound having at least one amino active hydrogen in the molecular structure. For example, primary alkylamines such as butylamine, octylamine, oleylamine, 2-ethylhexylamine, etc. , Primary alkanolamines such as monoethanolamine, 2-ethoxyethanolamine, 2-hydroxypropanolamine, aliphatic polyamines such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, m-xylenediamine, p-xylenediamine, Alicyclic polyamines such as 1,3-diaminocyclohexane and isophoronediamine, Mannich bases composed of polycondensates of polyamines with aldehyde compounds and mono- or polyhydric phenols, and aromatic compounds such as diaminodiphenylmethane. Family polyamines, polyamides polyamines and the like obtained by reacting the polyamines with polycarboxylic acids or dimer acids. Primary alkylamines and primary alkanolamines are preferable from the viewpoint of excellent storage stability when core-shell resin particles are used.

  The reaction between the bisphenol type epoxy resin and the amine compound can be carried out 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.

  Next, the resin component (B) forming the shell part used in the present invention is a resin (b) having a weight average molecular weight of 3,200 to 100,000 obtained by reacting a polyoxyalkyleneamine and a bifunctional epoxy resin. ).

As the polyoxyalkyleneamine, an alkylene oxide structural unit such as an ethyleneoxy structural unit or a 1,2-propyleneoxy structural unit or a 1,3-propyleneoxy structural unit is used as a repeating unit in the molecular structure, and one end of the molecular structure. Or the compound which has an amino group in both terminal is mentioned.
Here, the number of repeating units of the alkylene oxide structural unit is preferably 10 to 100 on average from the viewpoint of water dispersibility of the core-shell resin particles, and particularly the coating film hardness and the storage stability of the aqueous resin dispersion. From the point of balance with the nature, it is preferably 13 to 90, particularly preferably 15 to 75.

  In addition, when the active hydrogen equivalent of the polyoxyalkyleneamine is 400 g / eq or more, the stability of the core-shell resin particles in the aqueous medium becomes good, and when the polyoxyalkyleneamine is 2000 g / eq or less, the core-shell resin particles Can be prevented from crystallizing. Therefore, the active hydrogen equivalent is preferably in the range of 400 to 2000 g / eq.

  Specifically, such polyoxyalkyleneamines have the following structural formulas (1) to (3).

（式中、Ｒ^１は水素原子、メチル基、エチル基、プロピル基、又はｔ−ブチル基であり、Ｒ^２はエチレン基、１，２−プロピレン基、２，３−プロピレン基、１，３−プロピレン基であり、Ｒ^３はメチレン基、エチレン基、１，２−プロピレン基、２，３−プロピレン基、１，３−プロピレン基であり、ｎは繰り返し単位の平均で１０〜１００である。）

(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. .)

（式中、Ｒ^４はメチレン基、エチレン基、１，２−プロピレン基、２，３−プロピレン基、１，３−プロピレン基であり、Ｒ^２はエチレン基、１，２−プロピレン基、２，３−プロピレン基、１，３−プロピレン基であり、Ｒ^３はメチレン基、エチレン基、１，２−プロピレン基、２，３−プロピレン基、１，３−プロピレン基であり、ｎは繰り返し単位の平均で１０〜１００である。）

(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.)

（式中、Ｒ^２はそれぞれ独立的にエチレン基、１，２−プロピレン基、２，３−プロピレン基、１，３−プロピレン基であり、Ｒ^５は水素原子、メチル基、エチル基であり、ｐは繰り返し単位の平均は０〜５であり、ｘ、ｙ、ｚはそれぞれ繰り返し単位の平均で１〜１０である。）
で表されるものが特にコア・シェル状の樹脂粒子の水性媒体中での安定性が良好となる点から好ましい。
なお、上記構造式（１）〜（３）において下記構造式

(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.
In particular, it is preferable because the stability of the core-shell resin particles in the aqueous medium is improved.
In the structural formulas (1) to (3), the following structural formula

で表される繰り返し単位とするポリオキシアルキレン部分は、オキシエチレン基、オキシ−１，２−プロピレン基、オキシ−２，３−プロピレン基、オキシ−１，３−プロピレン基からなる群から選択される１種からなるポリオキシアルキレン構造を形成してもよいし、又は、２種以上がランダムに結合したポリオキシアルキレン構造、若しくは、２種以上がブロック状に結合したポリオキシアルキレン構造であってもよい。

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 the bifunctional epoxy resin and stability of the product. In the structural formulas (1) to (3), the value of n is particularly preferably 13 to 90, and particularly preferably 15 to 75.

  Examples of the bifunctional epoxy resin used for the production of the resin (b) include 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 type epoxy resins such as bisphenol Z type epoxy resins, biphenol type epoxy resins, dioxynaphthalenes, polycondensates of dihydroxybenzenes and epihalohydrins, glycidyl ethers of divalent diols, glycidyl esters of divalent carboxylic acids, etc. Those having an aromatic ring may be substituted with a hydrocarbon group or halogen. These can be used alone or in combination of two or more. Among these, bisphenol-type epoxy is preferable from the viewpoint of compatibility with the core portion and the coating film properties of the resulting aqueous dispersion.

  The reaction between the polyoxyalkyleneamine and the bifunctional epoxy resin can be carried out without solvent or in the presence of 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 resin (b) obtained by reacting the bifunctional epoxy resin with polyoxyalkyleneamine is characterized in that the weight average molecular weight is in the range of 3,200 to 100,000 as described above. When the weight average molecular weight is less than 3200, it is difficult to obtain stable core-shell resin particles, and when it is greater than 10,000, synthesis control is difficult. From the viewpoint of excellent balance, the weight average molecular weight of the resin (b) is preferably in the range of 4000 to 25000, particularly in the range of 4000 to 20000.

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”.
(Used polystyrene)
“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.

  When the resin (b) is produced, the reaction ratio between the bifunctional epoxy resin and the polyoxyalkyleneamine is such that the active hydrogen equivalent of the polyoxyalkyleneamine is a bifunctional epoxy resin from the storage stability of the resulting resin (b). It is preferable to react both in the range which becomes larger than the epoxy equivalent. In particular, in the present invention,

  Further, the resin (b) contains a polyoxyalkylene group derived from the polyoxyalkyleneamine in a proportion of 25 to 95% by mass in the resin (b), so that the stability of the core-shell resin particles is improved. It is preferable from the viewpoints of excellent adhesion to the substrate and coating film hardness.

  In the present invention, it is desirable to use a compound having a quaternary onium moiety in the resin (b) for the purpose of enhancing the water solubility of the resin component (B). 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.

（式中、ｎはメチレン基の繰り返し単位の平均で１〜５である。）

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

Examples of the method for obtaining the aqueous resin composition of the present invention include the following methods 1) to 3).
Method 1) A method in which water is dropped after the resin component (A) and the resin component (B) are uniformly mixed.
Method 2) A method of adding an aqueous solution of the resin component (B) to a solution obtained by dissolving the resin component (A) in an organic solvent such as butyl cellosolve.
Method 3) A method in which the resin component (A) is dropped into an aqueous solution of the resin component (B).

  Among the above methods, the above method 1) is particularly preferable because the core / shell resin particles can be stably produced. Examples of the homogenizing device used for the uniform mixing in the method 1) include a homodisper, a multi-axial stirring device, a high-pressure homogenizer, and a sonolator.

  It does not restrict | limit especially as a dripping method of water, It can carry out by continuous dripping and division | segmentation addition, and 10-90 degreeC can be used for water temperature. The water temperature is more preferably 20 to 80 ° C. in order to maintain uniform mixing of the resin components.

  The use ratio of the resin component (A) to the resin component (B) is preferably a ratio of (A) / (B) = 5/95 to 60/40. When the abundance ratio of the resin component (A) is less than 5, it becomes difficult to obtain stable core / shell resin particles, and when it is more than 60, the water resistance of the coating film is poor.

  The aqueous resin composition thus obtained is an aqueous resin dispersion in which the core-shell resin particles dispersed in the aqueous medium are in the range of an average particle diameter of 0.01 to 10 μm. It is preferable from an excellent point.

  As the aqueous resin composition of the present invention, resin components such as other polyester-based aqueous resins and acrylic-based aqueous resins may be used in combination within the range not impairing the characteristics of the present invention.

  Furthermore, the aqueous resin composition of the present invention can be used in combination with a curing agent in order to further improve the performance of the processed product, for example, adhesion to the substrate and corrosion resistance.

  Although it does not specifically limit as said hardening | curing agent, It is preferable to use an amino resin and a phenol resin from the point which is easy to obtain industrially, and is excellent in the above-mentioned performance of the hardened | cured material obtained.

  Examples of the amino resins include melamine resins derived from melamine and aldehyde compounds, guanamine resins derived from aldehyde compounds such as benzoguanamine and acetoguanamine, and urea resins derived from aldehyde compounds such as urea and thiourea. Can be mentioned. These can be used alone or in combination of two or more.

  Further, as the amino resin, those in which amino components such as melamine and urea are co-condensed, and those in which methylol groups in the resin are substituted with alcohols such as methanol, propanol, isopropanol, butanol and isobutanol may be used. it can.

  As the use ratio of the amino resin, the solid content in the amino resin is preferably 1 to 40 parts by mass, and more preferably 2 to 30 parts by mass with respect to 100 parts by mass of the resin solid content in the aqueous resin composition. It is.

  The phenol resin is not particularly limited as long as it is a compound in which a phenol and an aldehyde compound are subjected to a condensation reaction in the presence of a catalyst, and can be used alone or in combination of two or more.

  Examples of the phenols include phenol, o-cresol, m-cresol, p-cresol, o-tert-butylphenol, m-tert-butylphenol, p-tert-butylphenol, p-cyclohexylphenol, nonylphenol, and xylenol. Monohydric phenols, bisphenols such as bisphenol A, bisphenol F, tetramethylbisphenol F, bisphenol AD, bisphenol Z, naphthalenediols such as 1,5-dioxynaphthalene, 1,6-dioxynaphthalene, biphenols, Examples thereof include tetramethylbiphenol, and these can be used alone or in combination of two or more.

  As the catalyst, a basic catalyst or an acid catalyst can be used. Examples of the basic catalyst include alkali metal hydroxides such as potassium hydroxide and sodium hydroxide, amines, ammonia and the like, and a resol-type condensate is obtained. Examples of the acid catalyst include hydrochloric acid, phosphoric acid, oxalic acid, and the like, and a novolac type condensate is obtained.

  Although it does not specifically limit as a use ratio of the said phenol resin, It is preferable to use by 1-40 mass parts of solid content in a phenol resin with respect to 100 mass parts of resin solid content of an aqueous resin composition, More preferably, it is 2-2. 30 parts by mass.

  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”.
(Used polystyrene)
“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 (Synthesis of bisphenol type epoxy resin)
In a four-necked flask equipped with a thermometer, a stirrer, and a nitrogen gas introduction tube, 300 parts of a bisphenol A type epoxy resin (“EPICLON 850S” manufactured by Dainippon Ink & Chemicals, Inc.) with an epoxy equivalent of 188 g / eq, bisphenol A 87 .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 to obtain an epoxy resin having an epoxy equivalent of 480 g / eq. This is defined as (A-1).

Synthesis Example 2 (Synthesis of bisphenol type epoxy resin)
300 parts of bisphenol A type epoxy resin “EPICLON 850S” and 156 parts of bisphenol A were charged into a four-necked flask equipped with a thermometer, a stirrer, and a nitrogen gas introduction tube, and heated and homogenized at 100 ° C. To this, 1.4 parts of 4% aqueous sodium hydroxide solution was added, and the mixture was stirred at 160 ° C. for 7 hours. By adding 195.4 parts of butyl cellosolve and stirring uniformly, an epoxy resin having an epoxy equivalent of 2,200 g / eq and a nonvolatile content of 70% was obtained. This is defined as (A-2).

Synthesis Example 3 (Synthesis of amine modified product of bisphenol type epoxy resin)
300 parts of bisphenol A type epoxy resin “EPICLON 850S” and 161.2 parts of bisphenol A were charged into a four-necked flask equipped with a thermometer, a stirrer, and a nitrogen gas introduction tube, and heated and homogenized at 100 ° C. To this, 1.4 parts of 4% aqueous sodium hydroxide solution was added and stirred at 160 ° C. for 7 hours to obtain an epoxy resin having an epoxy equivalent of 2,250 g / eq. After adding 153.7 parts of butyl cellosolve to the reaction solution and stirring and homogenizing, 19.1 parts of diethanolamine was added, and the mixture was further stirred at 140 ° C. for 3 hours. Next, 52 parts of butyl cellosolve was added and stirred uniformly to obtain an amine-modified epoxy resin having a nonvolatile content of 70% by mass. This is defined as (A-3).

Synthesis Example 4 (Synthesis of amine modified product of bisphenol type epoxy resin)
300 parts of bisphenol A type epoxy resin “EPICLON 850S” and 87 parts of bisphenol A are charged into a four-necked flask equipped with a thermometer, a stirrer, and a nitrogen gas introduction tube, and heated and homogenized at 100 ° C. to give an epoxy equivalent of 470 g. An epoxy resin of / eq was obtained. To this, 0.1 part of a 50% by weight aqueous solution of tetramethylammonium chloride was added and stirred at 140 ° C. for 3 hours. After adding 165.8 parts of butyl cellosolve and stirring and homogenizing, 30.7 parts of monoethanolamine was added, and the mixture was further stirred at 140 ° C. for 3 hours. Next, 59.1 parts of butyl cellosolve was added and stirred uniformly to obtain an amine epoxy resin having a nonvolatile content of 65% by mass. This is defined as (A-4).

Comparative Synthesis Example 1 (Synthesis of amine modified product of bisphenol type epoxy resin)
A four-necked flask equipped with a thermometer, a stirrer, and a nitrogen gas inlet tube was charged with 300 parts of bisphenol A type epoxy resin “EPICLON 850S” and 26.9 parts of bisphenol A, and heated and homogenized at 100 ° C. An epoxy resin having an equivalent weight of 240 g / eq was obtained. 0.1 part of 50 mass% tetramethylammonium chloride aqueous solution was added here, and it stirred at 140 degreeC for 2 hours. After adding 81.7 parts of butyl cellosolve and stirring and homogenizing, 143 parts of diethanolamine was added, and the mixture was further stirred at 140 ° C. for 5 hours. Next, 35.7 parts of butyl cellosolve was added and stirred uniformly to obtain an amine-modified epoxy resin having a nonvolatile content of 80% by mass. This is defined as (A-5).

Synthesis Example 5 (Synthesis of resin component (b))
In a four-necked flask equipped with a thermometer, a stirrer, and a nitrogen gas inlet tube, the following structural formula x1

（式中の記号は下記の通りである。
Ｒ^１：メチル基
Ｒ^２：エチレン基、１，２−プロピレン基及び２，３−プロピレン基
Ｒ^３：エチレン基）
ｎ＝２２ （エチレン基／（１，２−プロピレン基及び２，３−プロピレン基の合計）のモル比が１９／３）
Ｒ^３：エチレン基）
で表されるポリオキシプロピレンアミン（ハンツマン社製「ジェファーミンＭ−１０００」活性水素当量５０５ｇ／当量）５００部を仕込み、６０℃に加熱混合した。その後、ビスフェノールＡ型エポキシ樹脂「ＥＰＩＣＬＯＮ ８５０Ｓ」１４５．７部を仕込み、１００℃で更に６ｈｒ加熱撹拌することによって、淡黄色の樹脂を得た。これを（Ｂ−１）とする。（Ｂ−１）の重量平均分子量は約４，７７０であった。（Ｂ−１）のＧＰＣチャート図を図１に示す。

(The symbols in the formula are as follows.
R ¹ : methyl group R ² : ethylene group, 1,2-propylene group and 2,3-propylene group R ³ : ethylene group)
n = 22 (Mole ratio of ethylene group / (total of 1,2-propylene group and 2,3-propylene group) is 19/3)
R ³ : ethylene group)
500 parts of polyoxypropyleneamine ("Jeffamine M-1000" active hydrogen equivalent 505 g / equivalent) manufactured by Huntsman Co., Ltd.) was added and heated to 60 ° C. Thereafter, 145.7 parts of a bisphenol A type epoxy resin “EPICLON 850S” was charged, and the mixture was further heated and stirred at 100 ° C. for 6 hours to obtain a light yellow resin. This is defined as (B-1). The weight average molecular weight of (B-1) was about 4,770. A GPC chart of (B-1) is shown in FIG.

Synthesis Example 6 (Synthesis of resin component (b))
A pale yellow resin was obtained in the same manner as in Synthesis Example 5 except that it was changed to 161.3 parts of bisphenol A type epoxy resin “EPICLON 850S”. This is defined as (B-2). The weight average molecular weight of (B-2) was about 7,500. A GPC chart of (B-1) is shown in FIG.

Synthesis Example 7 (Synthesis of resin component (b))
The same procedure as in Synthesis Example 5 was carried out except that 173.5 parts of bisphenol A type epoxy resin “EPICLON 850S” was obtained, and a short yellow resin was obtained. This is defined as (B-3). The weight average molecular weight of (B-3) was about 16,000.

Synthesis Example 8 (Synthesis of resin component (b))
In a four-necked flask equipped with a thermometer, a stirrer, and a nitrogen gas inlet tube, 500 parts of polyoxypropyleneamine ("Jeffamine M-600" manufactured by Huntsman, active hydrogen equivalent 300 g / equivalent) and bisphenol A type epoxy resin “EPICLON 850S” (243.4 parts) was charged, and the mixture was heated and stirred at 100 ° C. for 6 hours to obtain a pale yellow resin. This is defined as (B-4). The weight average molecular weight of (B-4) was about 3,000.
Comparative Synthesis Example 2 (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 (“EPICLON 1050” manufactured by Dainippon Ink and Chemicals, epoxy equivalent of 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 referred to as (B-5).

Examples 1-6 and Comparative Examples 1-3
Using the resins obtained in Synthesis Examples 1 to 8 and Comparative Synthesis Examples 1 and 2, aqueous resin compositions were prepared according to the formulations shown in Table 1. Table 1 shows the properties of each aqueous resin composition.
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.

（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 volatile solvent present in each varnish.)

Examples 7-12 and Comparative Examples 4, 5
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. Moreover, about water resistance, it is a result after performing a 7 day and a half immersion in a 40 degreeC water tank. Each test method and evaluation criteria 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).

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

FIG. 1 is a GPC chart of the resin (B-1) obtained in Synthesis Example 5. FIG. 2 is a GPC chart of the resin (B-2) obtained in Synthesis Example 6.

Claims (6)

An aqueous resin composition in which core-shell resin particles are dispersed in an aqueous medium, wherein the resin component (A) forming the core part of the resin particles has an epoxy equivalent of 400 to 4,000 g / equivalent. A weight average obtained by reacting a polyoxyalkyleneamine and a bifunctional epoxy resin, wherein the resin component (B), which is a bisphenol type epoxy resin or its amine-modified product (a) and forms the shell part of the resin particles, An aqueous resin composition, which is a resin (b) having a molecular weight of 3,000 to 100,000. The aqueous resin composition according to claim 1, wherein the resin (b) contains a polyoxyalkylene group derived from the polyoxyalkylene amine in a proportion of 25 to 95% by mass in the resin (b). The aqueous resin composition according to claim 1 or 2, wherein the resin (b) is obtained by reacting the polyoxyalkyleneamine having an active hydrogen equivalent of 400 to 2,000 g / equivalent with a bifunctional epoxy resin. . The aqueous resin composition according to claim 1, 2 or 3, wherein the core-shell resin particles dispersed in the aqueous medium have an average particle diameter in the range of 0.01 to 10 µm. The ratio of the resin component (A) and the resin component (B) constituting the core-shell resin particles is a mass ratio of (A) / (B) = 5/95 to 60/40. The aqueous resin composition according to any one of claims 1 to 4. The aqueous resin composition according to claim 5, wherein the nonvolatile content is 10 to 60% by mass.

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