KR100938432B1 - Water-soluble epoxy reisn, method of preparing the same, aqueous epoxy resin composition and method of forming a coating layer using the same - Google Patents

Abstract

In an aqueous epoxy resin having excellent coating properties and water resistance, a method of preparing the same, an aqueous epoxy coating composition, and a method of forming a coating film using the same, the aqueous epoxy resin reacts a bisphenol epoxy compound with a polyether glycol having a number average molecular weight of 200 to 3,000. Are manufactured. The aqueous epoxy resin is excellent in coating film properties such as adhesion, gloss, natural dryness, and water resistance, and can be usefully used for preparing an aqueous coating because it forms a transparent aqueous solution or an emulsion without using an emulsifier.

Description

WATER-SOLUBLE EPOXY REISN, METHOD OF PREPARING THE SAME, AQUEOUS EPOXY RESIN COMPOSITION AND METHOD OF FORMING A COATING LAYER USING THE SAME}

The present invention relates to an aqueous epoxy resin, a method for producing the same, an aqueous epoxy coating composition and a method for forming a coating film using the same. More specifically, the present invention relates to an aqueous epoxy resin having improved adhesion and gloss, a method of preparing the same, an aqueous epoxy coating composition, and a method of forming a coating film using the same.

Epoxy resin compositions are widely used in civil engineering and building resins. For example, the demand for the epoxy resin composition is increased as an inner wall, an outer wall, and a floor waterproofing material for preventing the ground cracking of a building. In addition, the epoxy resin composition is used as a special coating agent in a variety of industries, such as fiber, paper, automobile, sports, wood, construction, marine and the like.

Conventional commercialized epoxy resins include those prepared by condensation polymerization of bisphenol A type epoxy compounds (BPA) and epichlorohydrin (ECH) at various molecular weights in the presence of a base. The epoxy resin thus prepared is commonly referred to as diglycidyl bisphenol A epoxy. Examples of diglycidyl bisphenol A epoxy resins have been developed such as epoxy resin compositions having two epoxy groups in an epoxy chain and an epoxy equivalent of about 180 to 3,000.

The epoxy resin composition as described above contains a volatile organic substance harmful to the environment and the human body by using an organic solvent to lower the viscosity depending on the working method. Efforts have been made to reduce the use of organic solvents as health and environmental concern and legal restrictions on the use of organic solvents have increased. However, these reductions are not a fundamental solution.

There is an aqueous epoxy resin which is partially produced in the form of emulsion particles by forcibly dispersing the oil-based epoxy resin using an emulsifier, but in this case, a special equipment for dispersing and rotating at high speed such as a homo mixer is used as well as used for emulsifying. Since emulsifiers remain in the coating film, they have a negative effect on physical properties such as adhesion and water resistance, and thus are restricted in spreading the aqueous epoxy resin throughout the industry.

In order to solve the above problems, by introducing a hydrophilic monomer into the epoxy molecule without using an emulsifier, it is required to develop an aqueous epoxy resin capable of water solubility and excellent physical properties.

Accordingly, an object of the present invention is to provide an aqueous epoxy resin having improved coating film properties.

Another object of the present invention is to provide a method for producing an aqueous epoxy resin which is particularly suitable for producing the above-mentioned aqueous epoxy resin.

It is another object of the present invention to provide an aqueous epoxy coating composition comprising the above-mentioned aqueous epoxy resin.

Further, another object of the present invention is to provide a method for forming a coating film using the above-mentioned aqueous epoxy coating composition.

An aqueous epoxy resin according to an embodiment for achieving the above object of the present invention is a polyether having a number average molecular weight of 200 to 3,000 represented by 30 to 95% by weight of an epoxy compound containing at least a bisphenol epoxy compound and the following structural formula 1 Epoxy resin prepared by reacting 5 to 70% by weight of glycol.

...... (1)

...... (One)

(In Formula 1, m is an integer of 2 to 4, x is an integer satisfying the number average molecular weight range)

In one embodiment of the present invention, the epoxy compound and the polyether glycol may be prepared by reacting in a molar ratio of 1: 1 to 12: 1.

In one embodiment of the present invention, the aqueous epoxy resin may be prepared by further reacting the silane compound represented by the following Structural Formula 2.

...... (2)

...... (2)

(In formula 2, R ₁ represents a vinyl group, a halogen atom, a thiol group, an epoxy group, an acryl group, or an amino group, R ₂ represents an alkyl group having 1 to 4 carbon atoms, R ₃ represents an alkoxy group, n is from 0 to 0 Is an integer of 3 and y represents 0 or 1)

In the method for producing an aqueous epoxy resin according to an embodiment for achieving the above object of the present invention, the number average molecular weight represented by 30 to 95% by weight of the epoxy compound containing at least a bisphenol epoxy compound and the structural formula 1 is 200 An aqueous epoxy resin is prepared by reacting 5 to 70% by weight of polyether glycol, which is from 3,000 to 3,000.

An aqueous epoxy paint composition according to an embodiment of the present invention for achieving another object of the present invention described above is 30 to 95% by weight of an epoxy compound containing at least a bisphenol epoxy compound and the number average molecular weight represented by the formula (1) An aqueous epoxy resin prepared by reacting 5 to 70 wt% of a polyether glycol of 200 to 3,000; Water-soluble amine curing agents; Sieving pigments; At least one additive selected from the group consisting of antifoaming agents, leveling agents, viscosity modifiers, plasticizers and antioxidants; And water.

In addition, in the method for forming a coating film according to an embodiment for achieving another object of the present invention described above, 30 to 95% by weight of the epoxy compound containing at least a bisphenol epoxy compound and the number average molecular weight represented by the formula (1) An aqueous epoxy resin prepared by reacting 5 to 70 wt% of a polyether glycol of 200 to 3,000; Water-soluble amine curing agents; Sieving pigments; At least one additive selected from the group consisting of antifoaming agents, leveling agents, viscosity modifiers, plasticizers and antioxidants; And water is mixed to prepare an aqueous epoxy paint composition. The prepared aqueous epoxy coating composition is then applied onto the object to form a coating film.

The above-mentioned aqueous epoxy resin of the present invention is excellent in adhesion, gloss and natural drying properties, and in terms of physical properties, manufacturing method, and usability in comparison with emulsion-type aqueous epoxy by forced emulsification which can be produced only by using a conventional emulsifier. It has excellent characteristics. In addition, the aqueous epoxy resin of the present invention can be produced not only in an emulsion state but also transparently. Therefore, the water-based epoxy resin and the water-based epoxy resin composition according to the present invention can be usefully applied to various industrial coatings such as modifiers, fibers, automobiles, sports, wood, construction, and marine.

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to the aqueous epoxy resin, a manufacturing method thereof, an aqueous epoxy coating composition and a method of forming a coating film using the same according to the preferred embodiments of the present invention. However, the present invention is not limited to the following embodiments, and a person of ordinary skill in the art may implement the present invention in various other forms without departing from the technical spirit of the present invention.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise, and the terms "comprises" or "consists of" include, but are not limited to, features, numbers, steps, operations, components, parts, or parts described in the specification. It is to be understood that the combination is intended to be present, but not to exclude in advance the possibility of the presence or addition of one or more other features or numbers, steps, operations, components, parts or combinations thereof. Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art, and are not construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Aqueous epoxy resin and its manufacturing method

The aqueous epoxy resin according to the embodiments of the present invention comprises at least 30 to 95% by weight of an epoxy compound including at least a bisphenol epoxy compound and 5 to 70% by weight of polyether glycol having a number average molecular weight of 200 to 3,000 represented by the following Structural Formula 1. It is an epoxy resin manufactured by making it react.

...... (1)

...... (One)

In Formula 1, m is an integer of 2 to 4, x is an integer satisfying the number average molecular weight range.

Examples of polyether glycols that can be used in the preparation of the aqueous epoxy resin of the present invention include polyethylene glycols, polypropylene glycols, polybutylene glycols, and the like having a number average molecular weight in the range of 200 to 3,000. These may be used alone or in combination.

If the number average molecular weight of the polyether glycol is less than 200, the content of the polyether glycol is excessively increased and the number of the epoxy functional groups is relatively increased in order to ensure the water solubility of the epoxy resin, thereby decreasing the reactivity in forming the coating film and may be vulnerable to water resistance. . In addition, when the number average molecular weight of the polyether glycol exceeds 3,000, the viscosity of the coating composition may be excessively increased, and the coating film may be very soft, thereby lowering the mechanical properties of the coating film. Thus, the polyether glycols used in the preparation of the aqueous epoxy resin of the present invention preferably have a number average molecular weight in the range of about 200 to about 3,000.

In the aqueous epoxy resin of the present invention, when the content of the polyether glycol is less than 5% by weight, the water solubility of the epoxy resin may be lowered. In addition, when the content of the polyether glycol exceeds 70% by weight, the water resistance and hardness of the formed coating film may be lowered. Therefore, the content of the polyether glycol used in the preparation of the aqueous epoxy resin according to the embodiments of the present invention is about 5 to 70% by weight, preferably 20 to 50% by weight.

The epoxy compound used in the preparation of the aqueous epoxy resin of the present invention contains at least a bisphenol epoxy compound. Examples of bisphenol epoxy compounds include bisphenol A diglycidyl ether oligomer having a weight average molecular weight of 300 to 1,000, bisphenol F diglycidyl ether oligomer having a weight average molecular weight of 300 to 1,000, bisphenol AF having a weight average molecular weight of 300 to 1,000. Diglycidyl ether oligomer, and the like.

According to one embodiment of the present invention, the epoxy compound used in the preparation of the epoxy resin may further include a monoepoxy compound, a diepoxy compound, or a mixture thereof in addition to the bisphenol epoxy compound.

As the monoepoxy compound, aliphatic glycidyl ether, carboxyl glycidyl ester, aromatic glycidyl ether, cyclic aliphatic glycidyl ether and the like can be used. Specific examples of monoepoxy compounds include butyl glycidyl ether, phenyl glycidyl ether, ethylhexyl glycidyl ether, and allyl glycidyl ether. ), Cresyl glycidyl ether, and the like. These can be used individually or in mixture.

The diepoxy compound includes a diglycidyl ether compound or a modified diglycidyl ether compound. Specific examples of diepoxy compounds include hexanediol diglycidyl ether, butanediol diglycidyl ether, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, bisphenol AF diglycidyl ether, ethylene glycol diglycidyl ether, etc. are mentioned. In addition, specific examples of the modified diglycidyl ether compound include fatty acid modified diglycidyl ether, rubber modified diglycidyl ether, acrylic modified diglycidyl ether, and the like. These can be used individually or in mixture.

When using a modified epoxy compound together with a bisphenol epoxy compound as an epoxy compound according to one embodiment of the present invention, it is preferable to include 10% to 50% of the modified epoxy compound with respect to the total epoxy equivalent. When the modified epoxy compound contains less than 10% of the epoxy equivalent, the hardness of the coating film may be weak when forming the coating film. In addition, when more than 50% of the modified epoxy compound is included in the epoxy equivalent, the mechanical properties may be lowered and the curing rate may be delayed. Therefore, the epoxy compound used in the production of the epoxy resin of the present invention preferably contains a modified epoxy compound corresponding to 10% to 50% epoxy equivalent, and more preferably a modified epoxy compound of 10% to 30% epoxy equivalent. It may include.

In one embodiment of the present invention, the epoxy compound and the polyether glycol may be prepared by reacting in a molar ratio of 1: 1 to 12: 1. In addition, the aqueous epoxy resin according to an embodiment of the present invention may have an epoxy equivalent of 300 to 2,000.

In one embodiment of the present invention, the aqueous epoxy resin may be prepared by further reacting the silane compound represented by the following Structural Formula 2. The silane compound serves to improve the adhesion of the epoxy resin.

R _1- (CH ₂ ) n-Si (R ₂ ) y (R ₃ ) 3-y ... (2)

In Structural Formula 2, R ₁ represents a vinyl group, a halogen atom, a thiol group, an epoxy group, an acryl group or an amino group, R ₂ represents an alkyl group having 1 to 4 carbon atoms, R ₃ represents an alkoxy group, n is 0 to 3 Is an integer of and y represents 0 or 1.

When the content of the silane compound used to prepare the aqueous epoxy resin according to an embodiment of the present invention is less than 0.01% by weight, the effect of improving the adhesion of the epoxy resin is insignificant. In addition, when the content of the silane compound exceeds 10% by weight, there is a fear that the coating film properties of the epoxy resin such as mechanical strength become poor. Therefore, the content of the silane compound used to prepare the aqueous epoxy resin according to one embodiment of the present invention is 0.01 to 10% by weight, preferably 1 to 5% by weight. In this case, the aqueous epoxy resin may be prepared by reacting 30 to 94.99% by weight of the epoxy compound, 5 to 60% by weight of the polyether glycol compound, and 0.01 to 10% by weight of the silane compound.

Specific examples of the silane compound include vinyltrimethoxy silane, vinyltriethoxy silane, tris (2-methoxyethoxy) (vinyl) silane. ), (3-bromopropyl) trimethoxysilane, (3-chloropropyl) trimethoxysilane, (3-bromopropyl) trie (3-bromopropyl) triethoxysilane), (3-chloroopropyl) triethoxysilane, N- (2-aminoethyl) 3-amino-propyl-dimethoxymethyl silane (( N- (2-aminoethyl) 3-amino-propyl-dimethoxymethylsilane), (3-aminopropyl) triethoxysilane, (3-aminopropyl) trimethoxysilane ((3-aminopropyl ) trimethoxysilane), (3-glycidyl oxypropyl) trimethoxysilane, (3-glycidyl oxypropyl) triethoxysilane ((3-glycidyloxypropyl) tr iethoxysilane), (3-mercaptopropyl) triethoxysilane, (3-mercaptopropyl) trimethoxysilane, 3- (methacryl) propyl Triethoxysilane (3- (methacryl) propyltriethoxysilane), etc. These may be used alone or in combination, and (3-glycidyloxypropyl) trimethoxy for improving the adhesion of epoxy resins. Preference is given to using silane compounds comprising silane, N- (2-aminoethyl) 3-amino-propyl-dimethoxymethylsilane or mixtures thereof.

In the method for producing an aqueous epoxy resin according to the embodiments of the present invention, an epoxy compound and a polyethylene glycol compound are reacted in the presence of a catalyst to prepare an aqueous epoxy resin.

Examples of the catalyst used in the preparation of the aqueous epoxy resin according to the present invention include ammonium salt compounds, boron salt compounds, phosphonium compounds, imidazole compounds, tertiary amine compounds or mixtures thereof. Specific examples of the catalyst include triethylammonium chloride, triethylammonium bromide, triethylammonium iodide, tributylammonium chloride, and tributylammonium bromide Tributylammonium iodide, tetraethylammonium tetrafluoroborate, N, N-dimethyl-1,2-diaminoethane-tetrafluoroboronic acid (N, N-dimethyl-1, 2-diaminoethane- tetrafluroboric acid), ethyltriphenyl phosphonium chloride, ethyltriphenyl phosphonium iodide, imidazole, 1-methyl imidazole, Benzimidazole, trimethylamine, triethylamine, tripropylamine, tributylamine utylamine). These can be used individually or in mixture.

When the reaction temperature of an epoxy compound and a polyethyleneglycol compound is less than 100 degreeC, an epoxy compound may not fully activate and there exists a possibility that reactivity may fall. In addition, when the reaction temperature exceeds 150 ° C, secondary reaction may be accompanied by secondary ring opening reaction, and it is not preferable because it becomes difficult to control the reaction conditions. Therefore, the step of reacting the epoxy compound and the polyethylene glycol compound of the present invention is preferably carried out at a temperature of 100 ℃ to 150 ℃, more preferably may be carried out at 100 ℃ to 130 ℃. In addition, the step of reacting the epoxy compound and the polyethylene glycol compound is carried out with sufficient mixing using a stirrer so that the reaction proceeds smoothly.

Since the aqueous epoxy resin according to the embodiments of the present invention is excellent in solubility and dispersibility in water to form a transparent aqueous solution or emulsion without using an emulsifier, it is useful for the preparation of an aqueous paint having improved coating properties. Can be used.

Water based epoxy coating composition

The aqueous epoxy coating composition according to the embodiments of the present invention is at least 30 to 95% by weight of an epoxy compound including at least a bisphenol epoxy compound and 5 to 70% by weight of a polyether glycol having a number average molecular weight of 200 to 3,000 represented by the following Structural Formula 1 An aqueous epoxy resin prepared by reacting; Water-soluble amine curing agents; Sieving pigments; At least one additive selected from the group consisting of antifoaming agents, leveling agents, viscosity modifiers, plasticizers and antioxidants; And water.

...... (1)

...... (One)

In Formula 1, m is an integer of 2 to 4, x is an integer satisfying the number average molecular weight range.

The type and content of each of the aqueous epoxy resin, the water-soluble amine curing agent, the extender pigment, and the additive included in the aqueous epoxy coating composition of the present invention can be appropriately adjusted according to the use thereof. For example, the aqueous coating composition may include 10 to 50 wt% of the aqueous epoxy resin, 5 to 35 wt% of the water-soluble amine curing agent, 5 to 35 wt% of the extender pigment, 0.1 to 5 wt% of the additive, and the total weight of the composition. May contain excess water.

When the content of the water-based epoxy resin included in the water-based epoxy paint composition according to an embodiment of the present invention is less than 10% by weight, the content of the epoxy resin which acts as a main binder when forming the film is insufficient, so that the coating film properties such as mechanical properties are reduced. There is a concern. Moreover, when content of an epoxy resin exceeds 50 weight%, viscosity control is not easy and there exists a possibility that workability may fall. Therefore, the aqueous epoxy paint composition according to an embodiment of the present invention contains 10 to 50% by weight of the epoxy resin. Here, the description of the aqueous epoxy resin is substantially the same as described above, and further detailed description is omitted.

The water-soluble amine curing agent included in the water-based epoxy coating composition according to an embodiment of the present invention may be used as long as it is a generally known water-soluble amine curing agent regardless of its kind. For example, M2-0080 (Dipia, South Korea) having an active hydrogen equivalent weight (AHEW, 50%) of 220, a solid content (NV%) of 50, and an amine value (mg / KOH) of 310 may be used as a water-soluble amine curing agent.

The extender pigment included in the aqueous epoxy paint composition according to an embodiment of the present invention may be used as long as it is a known extender pigment regardless of its type. For example, extender pigments such as talc, mica, kaolin, sericite, titanium dioxide, zinc oxide and the like can be used.

In addition, the aqueous epoxy coating composition according to an embodiment of the present invention may include various additives in consideration of its use and physical properties. For example, additives such as plasticizers, antifoams, leveling agents, antioxidants, viscosity modifiers can be used.

Examples of the plasticizer that can be used in the aqueous epoxy coating composition according to the embodiments of the present invention include dioctyl phthalate, dibutyl phthalate, dimethyl phthalate, diethyl phthalate ), Dioctyl adipate, dioctyl sebacate, and the like. These can be used individually or in mixture. In addition, examples of the leveling agent that may be used in the aqueous epoxy coating composition according to the embodiments of the present invention include BYK-320 or BYK-331 (trade name of BYK Chemie Co., Germany). Examples of antioxidants include Tinuvin-292 (trade name of Ciba Specialty Chemicals; Switzerland). In addition, examples of the antifoaming agent that may be used in the aqueous epoxy coating composition according to the embodiments of the present invention include BYK-066, BYK-067, BYK-067A or BYK-354 (above, trade name of BYK Chemie; Germany) and the like. Can be.

The aqueous epoxy paint composition according to the embodiments of the present invention may have a viscosity of about 50 to 70 KU in consideration of workability, applicability, and the like.

The aqueous epoxy coating composition according to the embodiments of the present invention described above may be prepared in a transparent solution state or an emulsion state by dissolving and dispersing the epoxy resin evenly and stably in water without adding an emulsifier, a surfactant, an acidic compound, or the like. . Therefore, it is possible to prevent the problem of deterioration of adhesion, water resistance, etc. due to the remaining of the emulsifier in the existing coating composition, and to easily prepare a coating composition excellent in coating properties and workability without special equipment for dispersing epoxy resin at high speed. can do.

Formation method of coating film

In the method for forming a coating film according to embodiments of the present invention, first, at least 30 to 95% by weight of an epoxy compound including a bisphenol epoxy compound and a polyether glycol 5 to 70 having a number average molecular weight of 200 to 3,000 represented by Formula 1 above An aqueous epoxy resin prepared by reacting wt%; Water-soluble amine curing agents; Sieving pigments; At least one additive selected from the group consisting of antifoaming agents, leveling agents, viscosity modifiers, plasticizers and antioxidants; And water is mixed to prepare an aqueous epoxy paint composition. The prepared aqueous epoxy coating composition is then applied onto the object to form a coating film. The description of the aqueous epoxy resin and the aqueous epoxy coating composition is substantially the same as described above, and further detailed description is omitted.

The coating film formed using the aqueous epoxy coating composition may be left to stand at room temperature to naturally dry to enhance the hardness of the coating film. It is preferable that the manufactured coating film has an adhesiveness of 5B or more according to ASTM-D3359 method. Moreover, it is preferable that the manufactured coating film has a gloss characteristic of 97 or more according to ASTM D523 method.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the following examples are provided to illustrate the present invention, and the present invention is not limited to the following examples and may be variously modified and changed.

Preparation of Aqueous Epoxy Resin

<Example 1>

A four-necked flask of 2 L was equipped with a thermometer, condenser, stirrer and heater. Examples of the epoxy compound include about 190 g of bisphenol A (BPA) epoxy oligomer having an epoxy equivalent weight of about 190 and a weight average molecular weight of about 380, about 500 g of polyethylene glycol having a number average molecular weight of about 1,000, and about 250 ppm of triethylammonium chloride used as a catalyst. Was put into the flask, and the temperature was raised to about 130 ° C. under a nitrogen atmosphere. After the reaction was carried out while maintaining the temperature of about 130 ℃, as the reaction proceeds, the epoxy equivalent was measured to reduce the temperature to about 60 ℃ when the epoxy equivalent (g / eq) falls within the range of about 500 to about 530 deionized water The reaction was terminated by adding aliquots of about 690 g for about 10 minutes. As a result, an aqueous epoxy resin in a transparent state having an epoxy equivalent weight of about 870, a viscosity of Z3, and a solid content (NV%) of 60 was obtained.

<Example 2>

To a 2-liter four-necked flask, a thermometer, condenser, stirrer and heater were attached. Examples of the epoxy compound include about 190 g of bisphenol A (BPA) epoxy oligomer having an epoxy equivalent weight of about 190 and a weight average molecular weight of about 380, about 100 g of polyethylene glycol having a number average molecular weight of about 1,000, and about 250 ppm of triethylammonium chloride used as a catalyst. Was put into the flask, and the temperature was raised to about 130 ° C. under a nitrogen atmosphere. After the reaction was carried out while maintaining the temperature of 130 ℃, as the reaction proceeds, the epoxy equivalent was measured and when the epoxy equivalent (g / eq) falls within the range of about 200 to about 230, the temperature is lowered to 60 ℃ and 690 g deionized water The reaction was terminated by adding a liquid for 10 minutes. As a result, an aqueous epoxy resin in an emulsion having an epoxy equivalent weight of about 380, a viscosity of Z2, and a solid content (NV%) of 60 was obtained.

<Example 3>

Example 1 above, except that about 470 g of bisphenol A epoxy oligomer having an epoxy equivalent weight of about 470 and a weight average molecular weight of about 940, about 236 g of polyethylene glycol having a number average molecular weight of about 1,000, and about 897 g of deionized water were used. Substantially the same process was carried out to obtain an emulsion aqueous epoxy resin having a solids (NV%) of 50 and an epoxy equivalent of about 1,900.

<Example 4>

Solid content was carried out in the same manner as in Example 1, except that about 510 g of a bisphenol F-type (BPF) epoxy oligomer having an epoxy equivalent weight of about 170 and a weight average molecular weight of about 340 and about 650 g of deionized water were used. 60, Epoxy Equivalent 830 to give an aqueous epoxy resin in a transparent state.

Example 5

Example described above except that about 760 g of triglycidyl ether type epoxy oligomer having an epoxy equivalent weight of about 137 and a weight average molecular weight of 410, about 346 g of polyethylene glycol having a number average molecular weight of about 1,000, and about 692 g of deionized water. Substantially the same process as 1 was carried out to obtain an aqueous epoxy resin in a transparent state with a solid content of 60% and an epoxy equivalent of 380.

Comparative Example 1

KEM-128-70 (trade name of Kukdo Chemical, Korea) was prepared as an emulsion epoxy resin having an epoxy equivalent weight of 285 and a solid content (NV%) of 70.

Comparative Example 2

EM-101-50 (trade name of Kukdo Chemical, South Korea) was prepared as an emulsion epoxy resin having an epoxy equivalent of 1,000 and a solid content (NV%) of 50.

Preparation of Prepaint Composition

<Manufacture example 1>

Water-soluble amine curing agent M2-0080 (Dipai, South Korea) having an active hydrogen equivalent weight (AHEW, 50%) of 220, solid content (NV%) of 50, and amine number (mg / KOH) 310, about 39g, leveling agent about 0.5g, antifoaming agent 0.5 g, sieving pigment 34g and deionized water about 20g was sufficiently mixed at room temperature for about 60 minutes. The mixture was aged at room temperature for about 24 hours to prepare an aqueous prepaint composition. BYK-348 (trade name of BYK Chemie Co .; Germany) was used as a leveling agent, and R-902 (trade name of DuPont Co .; USA) was used as a sieving pigment. As the antifoaming agent, BYK-011 (trade name of BYK Chemie Co .; Germany) was used. The viscosity of the prepared aqueous curing agent composition was measured and found to be about 85 KU.

Preparation of Aqueous Epoxy Coating Composition

<Example 6>

About 100 g of the aqueous prepaint composition prepared in Preparation Example 1, about 148 g of the epoxy resin composition prepared in Example 1, and about 50 g of deionized water were sufficiently mixed for 5 minutes to obtain an aqueous epoxy coating composition having a viscosity of 56 KU.

<Examples 7 to 10 and Comparative Examples 3 to 4>

An epoxy coating composition was prepared in substantially the same manner as in Example 6 except for the kind and content of the epoxy resin composition and the water content. The components and contents used in the preparation of the epoxy coating composition and the viscosity of the epoxy coating composition obtained are shown in Table 1 below.

Table 1

Evaluation of coating film properties

The physical properties of the coating film formed using the aqueous epoxy coating compositions prepared in Examples 6 to 10 and Comparative Examples 3 to 4 were evaluated.

The aqueous epoxy resin compositions prepared in Examples 6 to 10 and Comparative Examples 3 to 4 were prepared with iron plates polished with sandpaper and degreased as objects to be coated. Each epoxy coating composition prepared in Examples 6 to 10 and Comparative Examples 3 to 4 was applied onto the iron plate to form a coating film. The thickness of the applied coating was measured to be about 70 μm to 75 μm. After the coating film formed on the iron plate was dried at room temperature for about 7 days, the adhesion and gloss of the coating film were evaluated.

Adhesion was evaluated using the method of ASTM-D3359, which is a standard measurement method of adhesion. In addition, gloss was evaluated by the method of ASTM D523 using E4460 of BYK Gardner. The evaluation results are shown in Table 2 below.

TABLE 2

In Table 2, in the ASTM-D3359 method for evaluating adhesion, a total of 100 cells were made by drawing a line with a knife on the formed coating film, and the state of the coating film was confirmed after attaching and removing the standard tape. Adhesion is evaluated as 5B, 4B, 3B, 2B, 1B and 0B, meaning that 5B is the best adhesion.

As shown in Table 2, the coating film formed using the aqueous epoxy coating composition prepared according to the present invention was shown to have excellent adhesion of 5B. In addition, in the evaluation of gloss, the coating film formed by using the water-based epoxy coating composition prepared according to the present invention was not only excellent in full light with a gloss of more than 97, but also was not easily discolored or glossed down even with changes in temperature and humidity. .

The natural dry state of the coating film was confirmed by measuring the time of the dry contact. Also known as tacky free, after drying the coating for a certain time, the hand was not sticky when touching the coating by hand. The drying rate of the coating film can be confirmed by evaluating the time required to be tacky-free. The coating film formed using the epoxy resin composition according to the present invention was found to be excellent in the natural drying characteristics within a twelve hour dry time.

The aqueous epoxy resin according to the embodiments of the present invention described above has excellent adhesiveness, gloss, and natural dryness, and has better physical properties than the emulsion-type aqueous epoxy by forced emulsification which can be produced only by using a conventional emulsifier. It has excellent characteristics in manufacturing method and usability. In addition, the aqueous epoxy resin of the present invention can be produced not only in an emulsion state but also transparently.

Therefore, the water-based epoxy resin and the water-based epoxy resin composition according to the present invention can be usefully applied to various industrial coatings such as modifiers, fibers, automobiles, sports, wood, construction, marine, and the like.

As described above with reference to the preferred embodiment of the present invention, those skilled in the art without departing from the spirit and scope of the present invention described in the claims below various modifications and It will be appreciated that it can be changed.

Claims (11)

30 to 95% by weight of an epoxy compound comprising at least a bisphenol epoxy compound and 5 to 70% by weight of a polyether glycol having a number average molecular weight of 200 to 3,000 represented by the following structural formula 1 and having an epoxy equivalent of 300 to 2,000 Aqueous epoxy resin.

...... (One) (In Formula 1, m is an integer of 2 to 4, x is an integer satisfying the number average molecular weight range) The aqueous epoxy resin of claim 1, wherein the epoxy compound and the polyether glycol are prepared by reacting at a molar ratio of 1: 1 to 12: 1. delete The aqueous epoxy resin of claim 1, wherein the aqueous epoxy resin is prepared by further reacting a silane compound represented by the following Structural Formula 2.

...... (2) (In formula 2, R ₁ represents a vinyl group, a halogen atom, a thiol group, an epoxy group, an acryl group, or an amino group, R ₂ represents an alkyl group having 1 to 4 carbon atoms, R ₃ represents an alkoxy group, n is from 0 to 0 Is an integer of 3 and y represents 0 or 1) The method of claim 4, wherein 30 to 94.99% by weight of the epoxy compound, 5 to 60% by weight of the polyether glycol compound and 0.01 to 10% by weight of the silane compound are reacted with respect to the total weight of the aqueous epoxy resin. Water-based epoxy resin. Reacting 30 to 95% by weight of an epoxy compound comprising at least a bisphenol epoxy compound and 5 to 70% by weight of a polyether glycol having a number average molecular weight of 200 to 3,000 represented by the following Structural Formula 1 and having an epoxy equivalent of 300 to 2,000 Process for producing an aqueous epoxy resin in the range.

...... (One) (In Formula 1, m is an integer of 2 to 4, x is an integer satisfying the number average molecular weight range) The method of claim 6, wherein the step of reacting the epoxy compound and the polyether glycol using at least one catalyst selected from the group consisting of ammonium salt compound, boron compound, phosphonium compound, imidazole compound and tertiary amine compound Process for producing an aqueous epoxy resin, characterized in that carried out. The method of claim 6, wherein the step of reacting the epoxy compound and polyether glycol is carried out at a temperature of 100 ℃ to 150 ℃. 30 to 95% by weight of an epoxy compound comprising at least a bisphenol epoxy compound and 5 to 70% by weight of a polyether glycol having a number average molecular weight of 200 to 3,000 represented by the following structural formula 1 and having an epoxy equivalent of 300 to 2,000 Aqueous epoxy resins; Water-soluble amine curing agents; Sieving pigments; At least one additive selected from the group consisting of antifoaming agents, leveling agents, viscosity modifiers, plasticizers and antioxidants; And An aqueous epoxy paint composition comprising water.

...... (One) (In Formula 1, m is an integer of 2 to 4, x is an integer satisfying the number average molecular weight range) 10 to 10% by weight of the aqueous epoxy resin, 5 to 35% by weight of the water-soluble amine curing agent, 5 to 35% by weight of the extender pigment, 0.1 to 5% by weight of the additive and excess water relative to the total weight of the composition An aqueous epoxy coating composition, comprising: 30 to 95% by weight of an epoxy compound comprising at least a bisphenol epoxy compound and 5 to 70% by weight of a polyether glycol having a number average molecular weight of 200 to 3,000 represented by the following structural formula 1 and having an epoxy equivalent of 300 to 2,000 Aqueous epoxy resins; Water-soluble amine curing agents; Sieving pigments; At least one additive selected from the group consisting of antifoaming agents, leveling agents, viscosity modifiers, plasticizers and antioxidants; And mixing water to prepare an aqueous epoxy paint composition. And A method of forming a coating film comprising applying a water-based epoxy coating composition on the object to form a coating film.

...... (One) (In Formula 1, m is an integer of 2 to 4, x is an integer satisfying the number average molecular weight range)