KR101351184B1 - Modified epoxyester moisture curing urethane coating composition and process for preparing the same - Google Patents

Abstract

The present invention relates to an epoxy ester-modified moisture-curable urethane coating composition and a method for producing the epoxy ester-modified moisture-curable urethane coating composition, a rheological epoxy ester resin having a number average molecular weight of 500 to 20,000; Moisture-curable urethane resin having a number average molecular weight of 500 to 2,000; It is an object of the present invention to provide a coating composition which is excellent in adhesion, workability and storage properties.
According to the present invention, the epoxy ester-modified moisture-curable urethane coating composition according to the present invention forms a coating film on the surface of the material to impart mechanical and chemical properties including corrosion resistance and at the same time, even when coated on an organic coating film, one-component small-type coating By maintaining the excellent adhesion and wear resistance and durability compared to two-component urethane, epoxy paint and has an excellent effect to increase the competitiveness of the product as a coating for the belt coating and marking during drum coating.

Description

Epoxy ester-modified moisture-curable urethane coating composition and manufacturing method thereof

The present invention relates to an epoxy ester-modified moisture-curable urethane coating composition and a method for producing the same.

In general, a drum is a product designed to transport various oils and raw materials in large quantities. The outside of the drum is coated with the company's logo or the name of the filling on the outside of the drum. When the name is coated on the primary coating layer, if the primary coating layer is dark or dark, it is difficult to determine the name, and the aesthetics are not beautiful. Lack of interlayer adhesion can also lead to peeling off. Therefore, coating the logo and the name on the bands such as white and yellow on the middle part of the stop, not only the effect of eye focus but also the aesthetic appearance is good and the risk of peeling of the coating disappears.

At present, the most widely used band coating coating is alkyd melamine, acryl melamine, natural drying type alkyd melamine of one-part high temperature baking type, and other two-component urethane paints may be used. One-component high-temperature baking type paints should be subjected to secondary high-temperature baking after coating. At this time, even though the primary coating layer has already been fully cured, the secondary coating is applied, and even though a coating film is formed, a significant decrease in adhesion force occurs in the adhesive force compared to the coating film coated on the material. Coating film defects frequently occur due to a decrease in adhesion. In addition, the power consumption is doubled by two high temperature burners, and the work time is also doubled because it has to pass through the burners as in the first painting.

Alkyd resins, acrylic resins, modified acrylic resins, epoxy resins, modified epoxy resins and urethane resins are used as coating resins that can be used for secondary decoration coating.

Regarding the conventional alkyd resin, Korean Patent Publication Nos. 10-2005-0063972 and 10-2007-0071312 disclose techniques for alkyd resin compositions having improved workability and adhesion.

However, alkyd resins and modified alkyd resins have disadvantages of poor alkali resistance, resulting in a decrease in physical properties of the coating film itself during storage or after exposure to air. In addition, the ester bond in the alkyd resin not only degrades adhesion, water resistance, and chemical resistance by hydrolysis during storage, but also seriously discolors the coating film depending on the baking temperature.

Acrylic resin can be divided into 1-component acrylic melamine high temperature baking type and 2-component acrylic urethane using a hardening | curing agent. In the acrylic melamine type, the discoloration of the primary coating becomes a problem due to the secondary baking, and the loss of energy and working time due to the secondary baking is enormous. In the case of two-component acrylic urethane, workability is remarkably decreased due to the limitation of pot life, and in case of natural drying, it requires three or more days of drying time to fully cure. Adhesion is also significantly reduced.

General high equivalent low molecular weight epoxy resins are not naturally dried and cannot be used as binders by themselves. In the above-mentioned paints, the adhesion to the alkyd melamine coating film, which is the primary coating surface, is remarkably inferior. In addition, considering the problems such as workability, power consumption, and work time reduction, research on the development of fundamental one-component natural drying type paints to improve adhesion, durability, weather resistance, and chemical properties on various organic coatings and metal materials Is needed.

In addition, in order to solve the problem of weak drying speed as a one-component natural drying paint, it is necessary to introduce a suitable drying accelerator and a reactive component to maintain excellent adhesion as a one-component type, and to dry quickly. There is a need for research on the development of paints that can prevent the gelling (GEL) phenomenon during storage to improve the storage properties and to improve the disadvantages of pigment precipitation problems that may occur due to the high pigment content.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a coating composition excellent in adhesion, workability and shelf life.

In one aspect of the present invention, the epoxy ester-modified moisture-curable urethane coating composition for achieving the above object is a rheological epoxy ester resin having a number average molecular weight of 500 to 20,000; And moisture-curable urethane resin having a number average molecular weight of 500 to 2,000; And a control unit.

Rheological epoxy ester resin is characterized in that the whey is 30% to 45%, the acid value is 5 or less.

Rheological epoxy ester resin is characterized by being obtained from an epoxy resin having an epoxy equivalent of 300 to 3,500 and a solid content of 55% or less and a fatty acid having 8 to 20 carbon atoms.

The fatty acid is at least one member selected from the group consisting of coconut fatty acid, dihydrate castor oil fatty acid, isononanoic fatty acid, soybean oil fatty acid and tall oil fatty acid.

Epoxy ester-modified moisture-curable urethane coating composition is characterized in that it further comprises one or more selected from the group consisting of reaction catalysts, curing accelerators, co-solvents and solvents.

Epoxy ester-modified moisture-curable urethane coating composition is 10 to 40 parts by weight of the modified epoxy ester resin; 3 to 15 parts by weight of the moisture-curable urethane resin; 0.1 to 2 parts by weight of the reaction catalyst; And 0.1 to 5 parts by weight of the curing accelerator; And a control unit.

Epoxy ester-modified moisture-curable urethane coating composition is 10 to 40 parts by weight of the modified epoxy ester resin; 3 to 15 parts by weight of the moisture-curable urethane resin; 0.05 to 10 parts by weight of the polymer dispersant; 10 to 50 parts by weight of pigment; 0.1 to 10 parts by weight of antisettling agent; 0.1 to 2 parts by weight of the reaction catalyst; 0.1 to 5 parts by weight of the curing accelerator; 10 to 40 parts by weight of the co-solvent; And a control unit.

In another aspect of the present invention, a method of preparing an epoxy ester-modified moisture-curable urethane coating composition in order to achieve the above object comprises: adding and mixing a rheology-based epoxy ester resin, a polymer dispersant, and a pigment having a number average molecular weight of 500 to 20,000; Step B for further mixing at least one selected from the group consisting of a reaction catalyst, a curing accelerator, a scavenger and a co-solvent to the mixture prepared from step A; And C step of mixing a moisture-curable urethane resin having a number average molecular weight of 500 to 2,000 to the mixture prepared from step B; And a control unit.

 Method for producing an epoxy ester-modified moisture-curable urethane coating composition is A 'step of grinding the mixture prepared from the step A between the step A and the step B; And further comprising:

As described above, according to the present invention, the epoxy ester-modified moisture-curable urethane coating composition according to the present invention may form a coating film on the surface of the material to provide mechanical and chemically excellent physical properties including corrosion resistance and at the same time be coated on the organic coating film. By maintaining the excellent adhesion, wear and durability compared to the one-component small-type paint, two-component urethane, epoxy paint, there is an excellent effect to increase the competitiveness of the product as a coating for the belt coating and marking during drum coating.

The preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings, in which the technical parts already known will be omitted or compressed for simplicity of explanation.

≪ Description of Coating Composition >

The present invention is a method for producing an epoxy ester-modified moisture-curable urethane paint containing a rheotropic epoxy ester resin having an OH group having a number average molecular weight of 500 to 20,000, a moisture-curable urethane resin having an isocyanate content of 3 to 16%, and a surface and internal drying accelerator. To provide.

According to the present invention, the epoxy ester-modified moisture-curable urethane coating composition reacts with the epoxy-ester resin OH group to the moisture-curable urethane resin NCO group, thereby maintaining the flexibility and anti-corrosive component of the epoxy ester and at the same time, curing and drying resistance of the urethane resin and adhesive weather resistance. As it has reactivity, it shows excellent adhesion on various organic coatings used as top coat, and it can reduce two baking processes to one when drum coating and improve productivity and energy consumption significantly.

In particular, in one preferred embodiment of the invention, the rheological epoxy ester coating composition of the present invention is cured at a designated drying time when only the epoxy ester resin is reacted with a catalyst or only the moisture-curable urethane resin is reacted. On the other hand, the physical properties are inferior because it does not proceed, and by allowing the epoxy ester resin to react with the moisture-curable urethane resin together, it is possible to secure dryness at a low temperature and more effective adhesion.

The epoxy ester-modified moisture-curable urethane coating composition of the present invention includes a rheotropic epoxy ester resin having a number average molecular weight of 500 to 20,000 and a moisture-curable urethane resin having a number average molecular weight of 500 to 2,000.

The rheology-based epoxy ester resin gives flexibility to the epoxy ester-modified moisture-curable urethane coating composition of the present invention, the number average molecular weight is used is 500 to 20,000, preferably 1,000 to 3,000. If the number average molecular weight is less than 500, a problem of brittleness of the final coating composition occurs, and if the number average molecular weight is more than 20,000, roll workability of a pickup roll or the like is deteriorated.

The rheological epoxy ester resin usable in the present invention is esterified by reacting an epoxy resin with a fatty acid, and in particular, the epoxy resin has an epoxy equivalent of 300 to 3,500, preferably 900 to 3,000, and a solid content of 55% or less, preferably It can be less than 50%. For example, epoxy YD 011, YD 014, YD 017, YD 019 resin, etc. may be used in Kukdo Chemical. Depending on the type of epoxy resin, a lot of difference occurs in the final physical properties and the adhesion on the organic coating.

In addition, the fatty acid may be a fatty acid having 8 to 20 carbon atoms, preferably 8 to 18 carbon atoms, more preferably coconut fatty acid, dihydrate caster oil fatty acid, soybean oil fatty acid, tall oil fatty acid, and the like. Can be used as

In a specific example of the invention, the rheological epoxy ester resin may be represented by the following formula (1).

[Chemical Formula 1]

The rheological epoxy ester resin may have a whey of 30% to 45%, preferably 32% to 40%, and an acid value of 5 or less, preferably 3 or less. The whey indicates the content of oil or fatty acid (wt%).

The rheological epoxy ester resin may be included in 10 to 40 parts by weight, preferably 15 to 25 parts by weight, when the epoxy ester resin content is less than 10 parts by weight of the coating film forming performance is insufficient due to poor adhesion. When the content exceeds 40 parts by weight, drying may be delayed and peeling may occur on the organic coating.

Coating composition of the present invention comprises a moisture-curable urethane resin with the rheology epoxy ester resin.

The moisture-curable urethane resin has a number average molecular weight of 500 to 2,000, preferably 600 to 1,800. If the number average molecular weight is less than 500, mechanical properties may be deteriorated. If the number average molecular weight is more than 2,000, it is not preferable in terms of material wettability and roll workability.

The moisture-curable urethane resin is used to improve the reactivity, paint chemical properties, adhesion and rust resistance in the coating composition. These moisture-curable urethane resins are mainly composed of polyurethane prepolymers having isocyanate groups at the chain ends, and they use chain extension or crosslinking reactions by reacting with water molecules.

That is, the isocyanate group reacts with water to turn into carbamic acid, and the carbamic acid is unstable, generating carbon dioxide, and the terminal group is changed to an amine group, and reacted with other isocyanate groups to form urea bonds. Get up. Generally, aromatic isocyanate compounds such as MDI (Methylene diisocyanate) and TDI (Toluene diisocyanate) are used a lot and the isocyanate content is usually used in the range of 3 ~ 16%.

The moisture-curable urethane resin is represented by the following formula (2) to achieve a crosslinking reaction with the chain extension.

(2)

The moisture-curable urethane resin may be included in 3 to 15 parts by weight, preferably 3 to 8 parts by weight. If the content is less than 3 parts by weight, a sufficient curing reaction of the coating may not be achieved, resulting in a decrease in adhesion performance on the organic coating. If the physical properties of the less than 15 parts by weight, the coating film is brittle, adhesion is degraded and adversely affect the paint storage properties. Such moisture-curable urethane resin may be used differently depending on the workability and physical properties required by the demand line, such as compatibility with the main component resin, the type of coating equipment, coating film strength, adhesion, drying properties.

 The coating composition of the present invention dissociates the double bond of the epoxy ester-modified moisture-curable urethane resin, forms a urea bond by the reaction of the isocyanate group with water, and dries quickly, maintains the softness and rust resistance of the epoxy ester resin, and hardens drying by urethane reaction It is possible to form a coating film that maintains excellent adhesion and durability in a short time on the dried organic coating film component through the process.

In a preferred embodiment of the present invention, the rheological epoxy ester coating composition is a moisture-curable urethane resin of 3 to 15 10 to 40 parts by weight of the rheological epoxy ester resin having a number average molecular weight of 500 to 20,000, the number average molecular weight of 500 to 2,000. It may include parts by weight.

In addition, the epoxy ester-modified moisture-curable urethane coating composition of the present invention may further include at least one of a polymer dispersant, a pigment, an antisettling agent, a curing accelerator, a catalyst, a cosolvent, a scavenger, and the like.

The polymer dispersant may be any dispersant known to be usable in the coating composition, and is not particularly limited to the kind thereof.

Since pigments affect color, hiding power and workability, it is important to maintain an appropriate content range in the paint composition. Preferably, in the present invention, the coloring and extender pigments are included in an amount of 10 to 50 parts by weight, preferably 20 to 40 parts by weight. If the content of the pigment is less than the above range, a sufficient concealing effect cannot be obtained, and if it exceeds the above range, the dispersion and storage stability of the coating composition are lowered.

In this case, the pigment should be used for products with low oil absorption and excellent weather resistance, and the use of some organic pigments can reduce the total amount of pigment used.

Meanwhile, the epoxy ester-modified moisture-curable urethane coating composition of the present invention includes a pigment selected from the group consisting of soluble low toxicity pigments, coloring and extender pigments, and mixtures thereof.

In addition, the rheology-based epoxy ester-modified moisture-curable urethane coating composition according to the present invention may further include a sedimentation inhibitor. Since the pigments described above are specific gravity of 2 to 5 and heavy, pigments may precipitate during paint storage, resulting in deterioration of physical properties of the coating composition or poor workability. Antisettling agents are used to prevent the precipitation of pigments, and are typically fume silica, organocray, bentonite, aerogel 300®, aerogels 972®, creton®, benton27®, benton 34® and benton 38® (DAGUSSA). , Cabot corporation, RHEOX) and one selected from the group consisting of a mixture thereof can be used.

The anti-settling agent may be included in an amount of 0.1 to 10 parts by weight, preferably 1 to 3 parts by weight. If the content is less than 0.1 parts by weight it is difficult to suppress the precipitation of the pigment, if it exceeds 10 parts by weight it is preferable to use properly within the above range due to poor appearance due to inadequate roll coat work.

Solvents that can be mixed well with the resin used are used, and affects the coating workability and paint properties such as coating appearance, foaming, paint spreading, drying properties. In particular, it should be used as natural drying, so solvents with high volatilization rate should be used and alcoholic solvents affecting urethane reaction should be excluded. In addition, care should be taken when using solvents with high volatility, since gelation may occur during paint storage. The solvent may be 2 to 3 selected from the group consisting of ether-based and ketone-based mixtures of which the evaporation boiling point belongs to 100 to 300 ℃.

Typical ethylene glycol monomethyl ether (methyl cellosolve), ethylene glycol monoethyl ether acetate (cellosolve acetate), ethylene glycol monobutyl ether (butyl cellosolve), diethylene glycol monobutyl ether, propylene glycol monomethyl ether , One kind selected from the group consisting of diethylene glycol butyl ether acetate, propylene glycol methyl ether acetate, ethylene glycol butyl ether acetate, and mixtures thereof, and a mixed solvent thereof. Preferably, butyl cellosolve, diacetone alcohol, methyl ethyl ketone (MEK), isopropyl acetone (MIBK), or the like may be used as the solvent, and toluene, xylene, or the like may be used as the co-solvent.

The co-solvent includes 10 to 40 parts by weight, preferably 20 to 30 parts by weight. If the content is less than the above range, there is a problem of lack of bubble generation and coating gloss, and if the content exceeds the above range, concealment defects and flow phenomena occur.

In addition, the epoxy ester-modified moisture-curable urethane coating composition according to the present invention may further comprise a curing accelerator.

In order to accelerate the curing by substituting the double bonds of the rheological epoxy ester resins, catalysts such as lead (Pb), cobalt, manganese and calcium are used, and 0.1 to 2 parts by weight. As may be included in an amount of 0.3 to 1 parts by weight. If the content is less than 0.1 parts by weight, it is difficult to substitute the double bond and the reaction does not proceed. If the content is more than 2 parts by weight, a problem occurs in the stability of the paint during storage. Is generated. In addition, one or two selected from the group consisting of dimethylethanol amine, triethylamine or triethanolamine and combinations thereof may be used to promote curing of the moisture-curable urethane resin. The amount of the curing accelerator is used in an amount of 0.1 to 5 parts by weight, and preferably, 0.1 to 2 parts by weight. If the content is less than 0.1 parts by weight, the curing rate of the urea bond is slowed, the initial adhesion failure occurs. If the content exceeds 5 parts by weight it is not possible to guarantee the paint storage properties due to the viscosity increase and gelation during paint production.

 The coating composition may use additives such as an antifoaming agent, a surface control agent and the like. The antifoaming agent prevents air bubbles, adjusts the surface tension of the paint, and removes large and small bubbles that may be generated during the painting operation. If the bubble is not completely removed, the coating performance, such as durability, corrosion resistance and water resistance, as well as damage to the appearance of the coating, is degraded, which significantly affects the coating performance. The surface modifiers and surface spreading aids are those known in the art to prevent spreading, foaming, surface conditioning and cratering.

<Description of Method>

1.Step A

In this step, a polymer dispersant and a pigment are added to the rheological epoxy ester resin having a number average molecular weight of 500 to 20,000, and a process of uniformly mixing by a stirrer is performed.

2. A ' step

The mixture mixed in step A is pulverized to a predetermined particle size or less by a sand mill, and in one embodiment of the present invention, the final particle size of the mixture is maintained to 20 μm or less.

3. Step B

The process of mixing at least one selected from the group consisting of a reaction catalyst, a curing accelerator, a scavenger and a cosolvent is carried out to the mixture prepared from step A.

4. Step C

A moisture-curable urethane resin having a number average molecular weight of 500 to 2,000 is mixed with the mixture prepared from step B to complete the coating composition.

The epoxy ester-modified moisture-curable urethane coating composition prepared according to the embodiment of the present invention has a viscosity of 70 to 110 ku, a gloss of 85 to 90% of the coating film, and particles of 12.5 to 18, measured by a Crebes-stopper viscometer. Have a μm.

The epoxy ester-modified moisture-curable urethane coating composition prepared in this way is excellent in adhesive strength, excellent durability and mechanical properties on the organic coating film is preferably applied for the band coating of the drum.

The coating composition can be applied directly on the baked dry coating film in the production of mass lines, which is an advantage of automatic coating, and thus maintains optimal properties in a natural dry state, thereby reducing the inconvenience and time required for conventional baking twice. Fast transfer and stacking are possible due to the adhesive force.

Furthermore, the composition is excellent in dryness and storage stability, which significantly improves the low storage stability and curing dryness of the conventional moisture-curable paints and the late drying and weakening of adhesive strength of epoxy ester paints, and has all the advantages of each resin. As a paint composition, it has a curing reaction as a natural drying, and can be coated on a metal material and an organic coating film to maintain excellent adhesion.

<Examples 1-3 and Comparative Examples 1-4>

To the coating composition was prepared in a composition as shown in Table 1 below.

First, a rheological epoxy ester resin or an epoxy resin or polyester resin, a polymer dispersant, and a sedimentation inhibitor were added to the reactor, and then stirred at a speed of 1200 rpm for 10 minutes with a stirrer. Stirring was carried out until the particles of the mixture was 50 ~ 60 ㎛, color pigments and sieving pigments were added thereto for 10 minutes high speed stirring at 1,200 rpm and then maintained by using a sand mill to a final particle size of 20 ㎛ or less.

Next, a reaction catalyst, a curing accelerator, a scavenger and a co-solvent were added to the reactor and stirred at a speed of 1000 rpm for 30 minutes. After stirring, moisture-curable urethane resin was added to prepare a composition having a viscosity of 70 to 80 ku.

The content of each composition for the coating compositions of Examples 1 to 3 and Comparative Examples 1 to 4 is as shown in Table 1 below. The unit is parts by weight.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Epoxy Ester ¹ 36 36 36 50 20 - - Epoxy Ester ² - - - - - 36 - Moisture Curing Urethane ³ 5 6 7 - 25 6 - Acrylic resin ⁴ - - - - - - 50 Essence ⁵ 5 5 5 5 5 5 5 Solvents ⁶ 10 10 9 5 7 10 5 Pigment Pigment ⁷ 34 33 32 32 32 33 32 Antisettling agents ⁸ 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Polymer Dispersants ⁹ 1.0 1.0 1.0 1.0 1.0 1.0 1.0 Catalyst ¹⁰ 0.5 0.5 0.5 1.0 0.5 0.5 0.5 Catalyst ¹¹ 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Catalyst ¹² 0.2 0.2 0.2 0.2 0.2 0.2 0.2 Reaction accelerators ¹³ 0.5 0.4 - - 0.5 0.4 - Reaction accelerators ¹⁴ - 0.1 0.5 - 0.1 0.1 - Antifoam ¹⁵ 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Material spreadability preparation ¹⁶ 0.1 0.1 0.1 0.1 0.1 0.1 0.1 Solvents ¹⁷ 5.4 4.4 4.4 3.4 4.3 4.4 3.9 Medicinal Agents ¹⁸ One 2 3 One 3 2 One week)
1: epoxy ester resin: number average molecular weight 500 to 20,000, light synthesis resin
2: epoxy ester resin: number average molecular weight 500 to 20,000, crude synthetic resin
3: Moisture hardening type urethane resin: Number average molecular weight 500 ~ 2000
4: acrylic resin: number average molecular weight 500 to 20,000 synthetic resin
5: Authentic Agent: Butyl Cellulsolve, Organic Ketone (MIBK, MEK)
6: solvent: xylene, toluene
7: Pigmented Pigment: TiO ₂ + Ceramic, Isoindolin Yellow
8: sedimentation inhibitor: Benton products
9: high molecular weight dispersant: high molecular weight block copolymer with pigment affinity functional group
10: catalyst: Cobalt
11: catalyst: 24% pb
12: catalyst: 5% Mn
13: Reaction accelerator: Dimethylethanol amine
14: reaction promoter: triethylamine
15: Defoamer: BYK 065
16: Material spreadability preparation: polyether modified polydimethylsiloxane liquid, acrylic copolymer
17: Solvents: xylene, toluene
18: Authentic Agents: Butyl Cellulsolve, Ethyl Cellulsolve

Experimental Example

In order to measure the physical properties of the coating compositions prepared in Examples 1 to 3 and Comparative Examples 1 to 4, the alkyd melamine, two-component urethane paint, and two-component epoxy paint were sprayed to a thickness of 20 to 30 μm, and then dried. After coating with a bar coating to a thickness of 20 ~ 30 ㎛ to dry for 48 hours, the physical properties were measured in the following manner.

Non-volatile matter (%)

After the sample was taken, the initial sample weight was measured, followed by hot air drying at 105 ° C. for 3 hours, and the weight of volatile matter relative to the initial sample weight was calculated based on Equation 1 below.

[Equation 1]

Nonvolatile matter (%) = ((Initial sample weight-weight of volatile) / Initial sample weight) × 100

Viscosity (Ku)

It measured using the Stormer viscometer at 25 degreeC.

Particle size (㎛)

It was measured with a particle size meter.

Dry state

Measure the tack-free time after applying the specified humidity film thickness of 75㎛

(Circle): No phenomenon which comes out in 10 minutes.

(Triangle | delta): There is no phenomenon which comes out in 20 minutes

×: phenomenon occurs after 30 minutes or more

Painting workability (bar coat & spray coating state)

The dry coating film thickness was coated with a thickness of 30 µm and visually compared to obtain a smooth coating film thickness, and then divided into three stages of good (○), good (△), and bad (×).

Adhesiveness

According to the cross-cut test method of ASTM D 3359, the cut made to the specimen was cut with a sheath and adhered to the cellophane tape so that the scratched part was evenly attached. Next, the peeling state of the coating film of the site | part where the cellophane tape was peeled off and a scratch was compared visually, and it divided and evaluated as follows.

○: No peeling.

(Triangle | delta): 80% or more of coating film remainder.

X: 50% or less coating film remaining.

Impact Resistance (Dupont, 1/2 "* 500g * 30cm)

Dupont impact tester was used to measure the cracks on the specimens produced in the size of 1/2 "× 500g × 30㎝, and according to the crack condition, there were three stages of good (○), good (△) and bad (×). Judgment was made separately.

Salt water spraying

Specimens made according to ASTM B117 were made with X-shaped lines according to method 2 (scraping method) of ASTM D1654. Subsequently, according to KS D 9502, a 5% NaCl aqueous solution was exposed to a salt spray machine sprayed at 35 ° C. to expose the time, and the state of the coating film was examined.

○: 1 mm or less on one side.

(Triangle | delta): 1-2 mm.

X: 2 mm or more.

Zhejiang Province

Each paint composition was stored at 40 ° C. for 1 month, and then the precipitation state of the paint composition was checked to see if a hard precipitate occurred:

○: no sedimentation and viscosity increase within 10ku

(Triangle | delta): There is some sediment and viscosity rises within 30ku.

X: generation of a large amount of precipitate and viscosity measurement is impossible

My alkalinity

According to KSM-5000-3411, the specimen was immersed in 5% aqueous NaOH solution for 48 hours according to the test method of immersion resistance of dry coating film, and then measured by bristering or 60 ° mirror gloss to obtain excellent (○) or good (△) It determined by dividing into three stages of defect (x).

Acid resistance

According to KSM-5000-3411, the specimen was immersed in 5% HCL aqueous solution for 48 hours according to the immersion resistance test method of dry coating film, and then measured by bristering or 60 ° mirror gloss to obtain excellent (○) or good (△) It determined by dividing into three stages of defect (x).

Physical property measurement results for the specimens of Examples 1 to 3 and Comparative Examples 1 to 4 are as shown in Table 2 below.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Non-volatile matter (%) 56 56 56 57 55 56 57 Viscosity (Ku25 ℃, Stormer
Viscometer) 75 72 70 70 80 72 72 Particle size (㎛) 20 20 20 20 20 20 20 Dry state (touch) ○ ○ △ △ ○ △ ○ Painting workability ○ ○ ○ ○ △ ○ ○ Adhesiveness (alkyd melamine position) △ ○ △ × × × × Adhesiveness (on urethane coating) ○ ○ △ × × × × Adhesiveness (on epoxy coating) ○ ○ △ △ × △ △ Acid resistance ○ ○ ○ △ △ ○ ○ My alkalinity ○ ○ ○ ○ ○ ○ ○ Salt spray ○ ○ △ ○ △ △ △ Impact Resistance (Dupont, 1/2 "* 500g * 30) △ ○ △ ○ × × × Hypotability (40 ℃, 30 days) △ ○ ○ ○ × × ○ Epoxy Ester: Urethane 6.5: 1 5.5: 1 4.5: 1 - 1: 1.3 5.5: 1 -

As shown in Table 2, it can be seen that the coating composition of Example 2 according to the present invention is excellent in workability, durability, coating hardness, impact resistance, corrosion resistance, adhesion on the organic coating.

On the other hand, in the case of Comparative Example 1 using only the existing epoxy ester resin, it can be seen that the adhesion on the organic coating film 'poor' significantly reduced and is not suitable because the drying is not fast, and in the case of Comparative Example 2 moisture-curable urethane resin Overuse can cause serious problems in paint storage. In addition, in the case of Comparative Examples 3 and 4 using the epoxy ester resin (2) and acrylic resin instead of the epoxy ester resin (1) of the present invention, the drying is also fast, but the adhesion on the organic coating is not good and the mechanical properties are not good. It can be seen.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. And the scope of the present invention should be understood as the following claims and their equivalents.

Claims (9)

10 to 40 parts by weight of a rheology epoxy ester resin having a number average molecular weight of 500 to 20,000;
3 to 15 parts by weight of a moisture-curable urethane resin having a number average molecular weight of 500 to 2,000;
0.05 to 10 parts by weight of the polymer dispersant;
10 to 50 parts by weight of pigment;
0.1 to 10 parts by weight of antisettling agent;
0.1 to 2 parts by weight of reaction catalyst;
0.1 to 5 parts by weight of a curing accelerator; And
10 to 40 parts by weight of a cosolvent; , &Lt; / RTI &
The rheology epoxy ester resin has a whey of 30% to 45%, an acid value of 5 or less,
The rheological epoxy ester resin is obtained from an epoxy resin having an epoxy equivalent of 300 to 3,500, a solid content of 55% or less, and a fatty acid having 8 to 20 carbon atoms,
The curing accelerator is at least one member selected from the group consisting of dimethylethanol amine, triethylamine, triethanolamine and combinations thereof
Epoxy ester-modified moisture-curable urethane coating composition. delete delete The method of claim 1,
The fatty acid is at least one member selected from the group consisting of coconut fatty acid, dihydrate castor oil fatty acid, isononanoic fatty acid, soybean oil fatty acid and tall oil fatty acid
Epoxy ester-modified moisture-curable urethane coating composition. delete delete delete A step of adding and mixing a rheological epoxy ester resin, a polymer dispersant and a pigment having a number average molecular weight of 500 to 20,000;
Step B of further mixing the reaction catalyst, the curing accelerator and the co-solvent to the mixture prepared from step A;
A 'step of grinding the mixture prepared from step A between step A and step B; And
C step of mixing the moisture-curable urethane resin having a number average molecular weight of 500 to 2,000 to the mixture prepared from step B; , &Lt; / RTI &
In the step A, the rheological epoxy ester resin is 10 to 40 parts by weight, the polymer dispersant is 0.05 to 10 parts by weight, and the pigment is 10 to 50 parts by weight,
In the step B, the reaction catalyst is 0.1 to 2 parts by weight, the curing accelerator is 0.1 to 5 parts by weight, the co-solvent is 10 to 40 parts by weight,
In the step C, the moisture-curable urethane resin is 3 to 15 parts by weight,
The curing accelerator in step B is characterized in that at least one selected from the group consisting of dimethylethanol amine, triethylamine, triethanolamine and combinations thereof
Method for producing an epoxy ester-modified moisture-curable urethane coating composition. delete