KR101532201B1 - Anti-corrosive coating composition for metal and articles coated therewith - Google Patents

Abstract

The present invention relates to an anticorrosive coating composition for metal, which is used in metal material-made industrial facilities, machines and parts thereof and accordingly increases anticorrosive property while having good resistance to drugs and harmful gas and having good properties like adhesive property of metal, flexibility, dryness, adhesive property, flexibility, storage stability, salt water resistance spraying property, acid resistance and alkali resistance, and articles coated with the same.

Description

TECHNICAL FIELD [0001] The present invention relates to an anticorrosive coating composition for metals, and to a coated article painted using the same. BACKGROUND ART [0002]

The present invention relates to a corrosion-resistant paint composition for a metal and a painted article painted using the same. More particularly, the present invention relates to industrial equipment made of a metal material, machinery, various parts thereof and the like, Corrosion resistant paint compositions for metals having both excellent resistance to chemicals and harmful gases and having excellent adhesion with metal as well as flexibility, dryness, adhesion, flexibility, storage stability, salt water repellency, acid resistance and alkali resistance, and The present invention relates to a coated article to be painted using the same.

Industrial equipments and machinery applying various metals are exposed to the corrosive environment, and their corrosion damage often affects the service life. Corrosion is a process of damaging metal structures or parts that can not afford a mechanical role due to the formation of oxides, which in turn can cause damage to the structure or structure, resulting in significant economic losses.

More specifically, in industrial facilities, machinery, and various parts made of metallic materials, chloride ions in the aqueous solution and chlorine ions in the sea water atmosphere are mainly influenced by the corrosive atmosphere under the general use conditions. It goes crazy. Even the smallest amount of chloride ion is likely to be dense to the structural design crevice, which can cause corrosion damage of crevice corrosion and stress corrosion cracking (SCC). Sulfur ions in the atmosphere also cause hydrogen corrosion and fatal corrosion damage associated with SCC.

In the case of air conditioners, industrial heat exchangers, etc., aluminum or copper or aluminum-copper alloy alloys or copper having good thermal conductivity in the conventional stainless steel or iron is used for rapid heat release during operation, but rust caused by oxidation occurs.

Particularly, corrosion due to salt and moisture, corrosion due to various chemicals (acid or alkali), corrosive noxious gas (SO _X , NO _{X ,} HCL, NH ₃ Etc.), corrosion due to changes in materials, corrosion caused by screwing or bonding of metal and nonmetal, resulting in an increase in energy consumption due to deterioration of the heat exchanger, an increase in processing cost for maintenance, increase in labor costs, There is an enormous cost loss such as pollution of the environment and soil due to leakage of liquid and gas due to cracks and corrosion of the tube portion, pipe portion and joint portion of the pipe, shortening the life span and increasing the maintenance cost.

Therefore, in the field of industrial facilities and machinery that apply various metals, a paint which protects them due to the deterioration of aesthetic appearance caused by corrosion occurring, reduction of the life of the structure, generation of industrial waste, and deterioration due to corrosion must be applied.

Background Art [0002] Conventional techniques relating to paints that can be applied to various metals to prevent corrosion are as follows.

Korean Patent No. 0367849 discloses a one-pack type high corrosion resistant acrylic cationic electrodeposition coating composition which is applicable to ONE-COAT top coat and has an acrylic-urethane-epoxy structure as a dry coating and has improved corrosion resistance, yellowing resistance and weatherability .

The one-pack type corrosion-resistant acrylic cationic electrodeposition coating composition is characterized in that, based on the total weight of the composition, (a) an epoxy-modified acrylic cationic electrodeposition resin having a primary hydroxyl group and an amino group produced by a graft reaction with an epoxy resin 30 to 50% by weight; (b) 10 to 20% by weight of a polyurethane crosslinking agent prepared by reacting isophorone diisocyanate halved with methylethylketoxime with trimethylolpropane; (c) 10 to 20% by weight of a polyurethane crosslinking agent prepared by reacting? -caprolactam with hexamethylene diisocyanate; (d) 20 to 30% by weight of at least one pigment selected from the group consisting of titanium dioxide, carbon black and aluminum silicate, and (e) a solvent.

Korean Patent No. 1233997 discloses a ceramic coating composition capable of coating the surface of various metallic materials or external facilities with an inorganic ceramic coating agent, a curing composition and a pearl material to enhance corrosion resistance and salt resistance.

The ceramic coating composition is prepared by mixing a mixture of tetraethylorthosilicate (TEOS): zinc acetate: ethanol: H ₂ O: HCl = 1: 0.01 to 5: 1 to 4: 1 to 8: (Glycidol), which is an organic monomer, is added in an amount of 0.01 to 10 wt% based on the total weight of the sol, and the mixture is stirred at a molar ratio of H ₂ SO ₄ in an amount of 0.001 to 5 wt% of the total weight and reacting at 50 to 80 ° C for 2 hours to form a first ceramic coating liquid; Based silane coupling agent 0.5 to 5, silicon carbide 5 to 10, isomerized alumina powder 7 to 15, zinc powder 0.5 to 10, silicon dioxide (SiO 2), silicon dioxide ₂ ) 17.5 to 35, 0.5 to 10 inorganic pigments composed of cobalt oxide (CoO + Co ₃ O ₄ ), water-soluble fluorescent pigment 0.1 to 1 and dispersant 0.1 to 2; And titanium dioxide-coated synthetic or natural mica at a weight ratio of 15 to 45: 5 to 10: 1.

Korean Patent No. 0896913 discloses a polyetheretherketone (PEEK) gas resin having adhesion and abrasion strength to a metal material, and n-methylmethyl 2-pyrrolidone containing a nitrogen element for controlling the viscosity of the gas resin At least one of a polar organic solvent containing at least one of NMP and dimethylformamide and at least one of Methyl Isobutyl Ketone, Methyl Ethyl Ketone, Cyclohexanone, And a fluorocarbon resin exhibiting a releasability function. The coating composition for metal coating according to the present invention is a coating composition for coating a metal.

Although the above-described conventional techniques disclose a coating composition for enhancing corrosion resistance of a metal material, the coating composition has poor adhesion and flexibility with a metal material and has excellent properties such as storage stability, salt water resistance, acid resistance and alkali resistance The coating composition is not disclosed.

In order to solve the problems of the prior art described above, the inventors of the present invention have repeatedly conducted research, and as a result, not only can the corrosion resistance be improved by applying to industrial equipments, machinery and various parts thereof, but also excellent resistance to various chemicals and noxious gases And also has excellent physical properties, and has developed a corrosion-resistant coating composition for metals.

Accordingly, it is an object of the present invention to provide a corrosion-resistant coating composition for metals having excellent resistance to various chemicals and noxious gases as well as being capable of improving corrosion resistance by being applied to industrial facilities, machinery, various parts thereof, And a coated article produced using the same.

Another object of the present invention is to provide a corrosion-resistant coating composition for metals having both good corrosion resistance as well as flexibility, dryness, adhesion, flexibility, storage stability, salt water repellency, acid resistance and alkali resistance, a method for producing the same, Thereby providing a coated article.

In order to achieve the above object, the present invention provides a curable composition comprising 35 to 55 parts by weight of a moisture-curing polyurethane resin, 15 to 25 parts by weight of a polymer-coated aluminum paste, 1 to 10 parts by weight of an additive, 25 to 35 parts by weight of a hydrocarbon solvent and an acetate- Corrosion-resistant coating composition for a metal.

In one embodiment of the present invention, as the aluminum paste coated with the polymer, acrylic coated aluminum may be used as a paste.

The wetting and dispersing agent, the water absorbing agent, the flowability additive, the drying promoting agent and the coloring agent may be used as the additives used in the corrosion-resistant coating composition for metal according to the present invention, but the present invention is not limited thereto.

In one embodiment of the present invention, the hydrocarbon solvent used in the present invention may be an aromatic hydrocarbon solvent, and the acetate solvent may be one of propylene glycol 1-methyl ether 2-acetate and butyl acetate or a mixture thereof .

The method for producing a corrosion-resistant coating composition for a metal according to the present invention comprises the steps of adding a wet dispersant and a flowable additive to a hydrocarbon-based solvent and mixing them (step 1); Adding a water absorbent and a moisture-curing polyurethane resin to the hydrocarbon-based solvent, mixing and then adding a polymer-coated aluminum paste and stirring (Step 2); And a moisture-curing polyurethane resin, a water absorbent, a drying promoter and butyl acetate, and then mixing and mixing the mixture of step 1 and step 2, respectively (step 3).

The present invention also provides a coated article coated with the corrosion-resistant coating composition for a metal.

INDUSTRIAL APPLICABILITY The present invention is applied to industrial equipments, machinery, and various parts thereof made of a metal material and has excellent resistance to corrosion resistance, various chemicals and noxious gases, and has excellent adhesion with metal, bending property, storage stability, It is possible to prevent fatal corrosion caused by a corrosive atmosphere and fatal corrosion damage caused by stress corrosion cracks by providing a corrosion resistant paint for metal which is excellent in both acid resistance and alkali resistance.

Further, by using the corrosion-resistant coating composition for metal according to the present invention, it is possible to prevent deterioration of aesthetic appearance caused by corrosion occurring in industry facilities and machinery fields where metal is applied, shortening the life of the structure, It is possible to increase not only the economic effect but also the environment-friendly effect.

Fig. 1 is a photograph of a specimen after the chemical resistance measurement test in Test Example 2 of the present invention. Fig.
Fig. 2 is a photograph of a specimen taken after the test for measuring the salt spray in Test Example 3 of the present invention. Fig.
Fig. 3 is a photograph of a specimen taken after a cass spray test in Test Example 4 of the present invention. Fig.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary meanings and should be construed in accordance with the technical meanings and concepts of the present invention.

The embodiments described herein are preferred embodiments of the present invention and are not intended to represent all of the technical ideas of the present invention, so that various equivalents and modifications may be substituted for them at the time of application of the present invention.

The corrosion-resistant coating composition for metal according to the present invention comprises 35 to 55 parts by weight of a moisture-curing polyurethane resin, 15 to 25 parts by weight of a polymer-coated aluminum paste, 1 to 10 parts by weight of an additive and 25 to 35 parts by weight of a hydrocarbon solvent and an acetate- Parts by weight.

The moisture-curing polyurethane resin used in the present invention has a structure in which an amine group is generated by reacting with the terminal NCO group of the urethane prepolymer and moisture in the air (water), and the amine group reacts with the NCO group to form an urea bond, Resin, which can be used in the art.

More specifically, the moisture-curing polyurethane resin used in the present invention according to the following reaction scheme reacts with an isocyanate group (NCO) and water to generate an amine group. The amine group reacts with isocyanate to form an urea bond, Curing is carried out.

 [Reaction Scheme 1]

The moisture-curing polyurethane resin used in the present invention may be prepared by mixing MDI-based isocyanates such as methylene diphenyl diisocyanate and modified methylene bisphenyl diisocyanate in order to improve flexibility, dryness, adhesion and storage stability so as to be suitable for a heat exchanger, use.

The moisture-curable polyurethane resin is contained in the corrosion-resistant coating composition for metal according to the present invention in an amount of 35 to 55 parts by weight.

When the moisture-curing polyurethane resin is contained in an amount of less than 35 parts by weight, the corrosion resistance paint composition for a metal according to the present invention may cause problems of adhesion to a material, durability against chemical resistance, If it is contained in an amount exceeding the above range, problems of flexibility, storage stability, salt water repellency (swelling of the coating film, lifting of the coating film) may occur.

In one embodiment of the present invention, the polymer-coated aluminum paste is a paste prepared using acrylic coated aluminum.

The acrylic-coated aluminum paste used in the present invention may be prepared and used, or those commercially available in the art may be used.

When the aluminum-coated aluminum paste containing less than 15 parts by weight of the acrylic-coated aluminum paste in the corrosion-resistant coating composition for metal according to the present invention may cause problems such as discoloration, swelling and peeling of the chemical resistance (acid, alkali) If it is contained in an amount exceeding a part by weight, there may arise a problem that the viscosity of the paint increases and the color becomes dark (luminance declines).

The additives included in the corrosion-resistant coating composition for a metal according to the present invention are a wetting and dispersing agent, a water absorbing agent, a flowable additive, a drying promoting agent and a coloring agent.

The wetting and dispersing agent, the water absorbent, the flowability additive, the drying promoter and the coloring agent may be those generally used in the art to which the present invention pertains. The corrosion inhibiting coating composition for metal according to the present invention may contain 1 to 10 parts by weight of an additive .

By adding the wetting and dispersing agent to the corrosion-resistant coating composition for metal according to the present invention, it is possible to suppress the generation of seeding and dust due to the reaction of the pigment and resin which may occur during coating, Improvement in appearance, prevention of bad appearance, and minimization of fatigue of workers.

The wetting and dispersing agent is preferably included in the corrosion-resistant coating composition for a metal according to the present invention in an amount of 0.5 to 2.0 parts by weight.

By adding a water absorbent to the corrosion-resistant coating composition for metal according to the present invention, gelation due to moisture can be suppressed during storage of the coating.

The waterborne corrosion-inhibiting coating composition for a metal according to the present invention preferably comprises 0.5 to 3.0 parts by weight of the water absorbent.

If the water absorbing agent is contained in an amount of less than 0.5 part by weight in the corrosion-resistant coating composition for metal according to the present invention, the viscosity of the paint may increase and the paint may gel.

By using the flowable additive in the corrosion-resistant coating composition for metal according to the present invention, it is possible to provide an effect of preventing stains, blisters, and appearance degradation due to the flow of the coating liquid during the coating operation.

It is preferable that the flowable additive is included in 1.0 to 4.0 parts by weight in the corrosion-resistant coating composition for a metal according to the present invention.

If the amount of the flowable additive is less than 1.0 part by weight in the corrosion-resistant coating composition for metal according to the present invention, it may cause problems such as stain, swelling, deterioration of appearance and lack of hiding power due to flow- There arises a problem of smoothness and reduced brightness of the painted surface.

By adding a drying promoter to the corrosion-resistant coating composition for metal according to the present invention, the drying time for the coating can be increased.

The drying accelerator is preferably included in the corrosion-resistant coating composition for a metal according to the present invention in an amount of 0.01 to 0.5 parts by weight.

If the drying accelerator is contained in an amount of less than 0.01 part by weight, the effect of improving the drying property of the coating composition may be insufficient. If the coating composition contains more than 0.5 parts by weight of the coating accelerator, It can cause stagnation phenomenon.

The coloring agent used in the present invention is selected according to the color to be colored in the product, and can be easily selected by those skilled in the art.

The additives included in the corrosion-resistant coating composition for a metal according to the present invention may further include leveling agents, anti-cracking agents, and anti-settling agents in order to complement the physical properties of the additives.

As the hydrocarbon solvent contained in the corrosion-resistant coating composition for metal according to the present invention, an aromatic hydrocarbon solvent can be used. As the acetate solvent, propylene glycol 1-methyl ether 2-acetate and butyl acetate Or a mixture thereof may be used, but the present invention is not limited thereto. Examples of the solvent included in the corrosion-resistant coating composition for a metal according to the present invention include aromatic solvents such as toluene and xylene.

In one embodiment of the present invention, it is preferable that the corrosion resistant paint composition for metal contains 25 to 35 parts by weight of a hydrocarbon solvent and an acetate solvent.

Example

The present invention will be described with reference to the following examples, which do not limit the scope of the present invention.

Example  One

As a first step, a wet dispersant is mixed in a hydrocarbon solvent, stirred at 300 to 500 rpm for 10 to 20 minutes, added with a fluidity additive, And homogeneously stirred and dispersed for 30 minutes.

Then, in the second step, a water-absorbing agent A and a moisture-curing polyurethane resin are sequentially blended with the hydrocarbon-based solvent, and the mixture is homogeneously stirred at 300 to 500 rpm for 10 to 20 minutes. Then, the aluminum- rpm for 20 to 30 minutes.

Finally, in the third step, the moisture-curing polyurethane resin is mixed with butyl acetate, water absorbent B and drying promoter in order, and the mixture is homogeneously mixed at 300 to 500 rpm for 20 to 30 minutes. Thereafter, And then the mixture was stirred at 500 to 1000 rpm for 20 to 30 minutes. Thereafter, the mixture prepared in the second step was added thereto and stirred while being uniformly mixed at 500 to 1000 rpm for 20 to 30 minutes. Thus, To prepare a coating composition. When used, it was applied to aluminum material of 99% purity or more with thin plate (0.1 ~ 0.5 mm) by brush painting or spraying and dried at room temperature (20 ~ 25 ℃) for about 24 hours to form dry film of 20 ~ 30 ㎛.

Raw material Amount of blending
(Parts by weight) Step 1 One Hydrocarbon solvent (trade name: KOCOSOL # 100, SK Energy) 12.0 2 Wet dispersant (trade name: EFKA-5044, EFKA) 1.0 3 Fluid additive (trade name: FRGEL, UION CHEMICALS) 2.0 4 Acetate solvent (trade name: DOWNANOL PMA GLYCOL ETHER ACETATE, DOW) 2.7 Step 2 5 Hydrocarbon solvent (trade name: KOCOSOL # 100, SK Energy) 12.8 6 Water absorbent A (trade name: SUPERSORB T1, KPX LIFE SCIENCE) 0.9 7 Polyurethane resin (trade name: KUR-285-100, Samhwa paint) 20.0 8 Aluminum paste (trade name: ALUMINUM PASTE 6255, ECKART) 20.0 Step 3 9 Polyurethane resin (trade name: KUR-285-100, Samhwa paint) 26.0 10 Solvent (butyl acetate) 1.7 11 Water absorbent B (trade name: TRI ETHYLORTHO FORMATE, HULS) 0.8 12 10% of dry promoter (trade name: SONGSTAB TL-100, SOGWON) 0.1

Comparative Example  One

A coating composition was prepared in the same manner as in Example 1, except that the components shown in Table 2 (in particular, a paste made of silver powder not coated with acrylic were used, unlike in Example 1) To prepare a dried coating film.

Raw material Amount of blending
(Parts by weight) Step 1 One Hydrocarbon solvent (trade name: KOCOSOL # 100, SK Energy) 12.0 2 Wet dispersant (trade name: EFKA-5044, EFKA) 1.0 3 Fluid additive (trade name: FRGEL, UION CHEMICALS) 2.0 4 Acetate solvent (trade name: DOWNANOL PMA GLYCOL ETHER ACETATE, DOW) 2.7 Step 2 5 Hydrocarbon solvent (trade name: KOCOSOL # 100, SK Energy) 18.8 6 Water absorbent A (trade name: SUPERSORB T1, KPX LIFE SCIENCE) 0.9 7 Polyurethane resin (trade name: KUR-285-100, Samhwa paint) 20.0 8 Aluminum paste (Product name: ALUMINUM PASTE 3122AR, SILVERLINE) 15.0 Step 3 9 Polyurethane resin (trade name: KUR-285-100, Samhwa paint) 25.0 10 Solvent (butyl acetate) 1.7 11 Water absorbent A (trade name: TRI ETHYL ORTHO FORMATE, HULS) 0.8 12 10% of dry promoter (trade name: SONGSTAB TL-100, SOGWON) 0.1

Comparative Example  2

The coating compositions were prepared in the same manner as in Example 1, except that the ingredients shown in Table 3 (in particular, using a paste made of silver powder not coated with acrylic, unlike Example 1) To prepare a dried coating film.

Raw material Amount of blending
(Parts by weight) Step 1 One Hydrocarbon solvent (trade name: KOCOSOL # 100, SK Energy) 10.0 2 Wet dispersant (trade name: EFKA-5044, EFKA) 1.0 3 Fluid additive (trade name FRGEL, UION CHEMICALS) 2.0 4 Acetate solvent (trade name: DOWNANOL PMA GLYCOL ETHER ACETATE, DOW) 2.7 Step 2 5 Hydrocarbon solvent (trade name: KOCOSOL # 100, SK Energy) 14.8 6 Water absorbent A (trade name: SUPERSORB T1, KPX LIFE SCIENCE) 0.9 7 Polyurethane resin (trade name: KUR-285-100, Samhwa paint) 20.0 8 Aluminum PASTE (trade name: ALUMINUM PASTE 5552ER, SHOWA ALUMINUM) 20.0 Step 3 9 Polyurethane resin (trade name: KUR-285-100, Samhwa paint) 26.0 10 Solvent (butyl acetate) 1.7 11 Water absorbent B (trade name: TRI ETHYL ORTHO FORMATE, HULS) 0.8 12 10% of dry promoter (trade name: SONGSTAB TL-100, SOGWON) 0.1

Test Example  One

(0.15 mm) of a purity of 99% or more of an aluminum thin plate material (0.15 mm) applied to a fin tube for a heat exchanger and a coating film coated with the coating liquid of Example 1, Comparative Example 1 and Comparative Example 2 were subjected to the following physical property tests. Respectively.

How to measure property

* Appearance of coating film: The surface state, swelling and discoloration degree are visually observed in the dried film

* Adhesion: The dried film is scratched with 11 pieces at intervals of 1 mm to make 100 squares. Adhesion is made to the area with 3M transparent tape, then peeled off to reveal the degree of the space where the coating has fallen In the case of good)

* Storage stability: The prepared solution is put into a 0.5 L TIN can, and the upper part is sealed so that it does not come into contact with air, then left at room temperature (20 ° C) for 3 months and then the top is opened to lump, And the occurrence of the coating of

* Flexibility: For coated specimens, it is necessary to orient the coated side upwards at the top of the ream (diameter 1/2 inch) to make the bending test equipment, and then to grasp cracks, peeling, peeling, etc. on the specimens folded 180 degrees downward.

* Salt flushing water: 1) KS D9502 salt water spray test equipment maintaining the temperature of 35 ℃ according to the spray test method, the effective surface of the test piece is set to 25 ± 5 ° with respect to the vertical line, and then 5% After spraying with salt water for a time specified by sodium chloride aqueous solution (pH 6.5 to 7.5), examination of swelling, peeling, and recording phenomenon of the coating film surface is examined

2) In order to compare the degree of corrosion and corrosion diffusion relative to the material, X-CUT was applied to the bottom of 1/3 of the formed film surface with a sharp knife to spray the salt water for a prescribed time, and then the X- ), Swelling, erosion, corrosion, peeling, etc.

* Acid resistance: After dissolving 10% of reagent sulfuric acid (purity: 95% or more) in distilled water and drying it, about 1 g was dropped to the formed film surface by drying, and after standing for 16 hours at room temperature (20 ° C.), discoloration, Etc.

* Alkali resistance: After dissolving 10% of reagent sodium hydroxide (purity: 98% or more) in distilled water and drying it, about 1g is dropped to the formed film surface by drying and left for 16 hours at room temperature (20 ° C) , Peeling, etc.

division Aluminum sheet material Example 1 Comparative Example 1 Comparative Example 2 Surface coating
Appearance condition - Good Good Good Attachment - 100/100 100/100 100/100 Flexibility (1/8 inch) - Good Good Good Storage stability - Good Good Good Salt water silent
(4,100 hours) Overall corrosion of the material Good X-CUT region
Swelling occurs X-CUT region
Swelling occurs Acid resistance
_{(10% H 2 SO 4/} 20 ℃ / 16 hours) Material decolorization Good Good Discoloration occurs Alkali resistance
(10% NAOH / 20 < 0 > C /
16 hours) Material corrosion
And dissolution Good Swelling occurs Good

The results are shown in Table 4. Referring to Table 4, when coated with a corrosion-resistant coating composition for metal made of an aluminum-coated acrylic paste and a moisture-curing polyurethane resin according to the present invention, compared with Comparative Examples 1 and 2, Silicate, acid resistance and alkali resistance.

Test Example  2- Chemical resistance measurement test

(0.15 mm) having a purity of 99% or more, which is applied to a fin tube for a heat exchanger, was coated with the coating composition of Example 1, and the aluminum sheet material itself was coated with H ₂ SO ₄ on the left side at room temperature (20 ° C.) NaOH was dropped on the surface of the film and allowed to stand for 16 hours. Then, the chemical resistance test was conducted under the conditions of recording, discoloration, swelling and peeling of the film, and photographs thereafter were shown in FIG. Fig. 1 (a) is a photograph of an aluminum thin plate material coated with the coating composition of Example 1, and Fig. 1 (b) is a photograph of the aluminum thin plate material itself.

1, recording, discoloration, swelling and exfoliation were observed in the aluminum foil itself. However, the coating film coated with the corrosion-resistant coating composition for a metal of the present invention was not observed in recording, discoloration, swelling and peeling. From this, it can be seen that the corrosion-resistant coating composition for metal of the present invention has excellent chemical resistance.

Test Example  3- Salt water silent  Measurement test

In order to evaluate the degree of corrosion on the aluminum foil material itself coated with the coating composition of Example 1 on the aluminum foil material (0.15 mm) having a purity of 99% or more and applied to the fin tube for the heat exchanger itself, The measurement was carried out over 4,100 hours according to the moisture-inactivity measurement method, and the photographs thereafter were taken and shown in Fig. Fig. 2 (a) is a photograph of an aluminum thin plate material coated with the coating composition of Example 1, and Fig. 2 (b) is a photograph of the aluminum thin plate material itself.

2, after the test according to the present invention, the aluminum foil itself was considerably corroded, but the coated film coated with the corrosion-resistant coating composition for metal of the present invention was not corroded. From this, it can be seen that the corrosion-resistant coating composition for metal of the present invention is excellent in corrosion resistance.

Test Example  4- cass  Spray test (Prompted salt spray test)

In order to determine the degree of corrosion of the aluminum foil material itself with respect to the coating of the aluminum foil material (0.15 mm) having a purity of 99% or more applied to the fin tube for a heat exchanger by the coating composition of Example 1 and the salt foaming agent itself, ASTM B368 CASS spray test (Copper-Accelerated Acetic-Salt Spray Testing) was performed. As the test conditions, distilled water: sodium chloride was dissolved in 95: 5 parts by weight, then 0.25 g / L of cupric chloride was added, and the pH (hydrogen ion concentration index) was adjusted to 3.1 to 3.3 using about 0.6 part by weight of 1 mole of hydrochloric acid Respectively. The temperature in the atomizer was maintained at 50 캜 and spraying test was carried out over 150 hours, and the photographs thereafter were taken and shown in Fig. Fig. 3 (a) is a photograph of an aluminum thin plate material coated with the coating composition of Example 1, and Fig. 3 (b) is photographs of an aluminum thin plate material itself.

Referring to FIG. 3, after the test according to the present invention, the aluminum foil itself was considerably corroded, but the coated film coated with the corrosion-resistant coating composition for metal of the present invention was not corroded. From this, it can be seen that the corrosion-resistant coating composition for metal of the present invention is excellent in corrosion resistance.

Claims (11)

35 to 55 parts by weight of a moisture-curing polyurethane resin, 15 to 25 parts by weight of an aluminum paste coated with a polymer, 1 to 10 parts by weight of an additive, and 25 to 35 parts by weight of a hydrocarbon solvent and an acetate solvent, based on 100 parts by weight of the coating composition ,
The polymer-coated aluminum paste comprises 45 to 65% by weight of an aluminum-coated aluminum powder and 35 to 55% by weight of naphtha having a carbon atom number of 6 to 12 at a boiling point of 90 to 200 ° C,
Wherein the additive comprises 0.5 to 2.0 parts by weight of a wet dispersant, 0.5 to 3.0 parts by weight of a water absorbent, 1.0 to 4.0 parts by weight of a flowable additive, and 0.01 to 0.5 parts by weight of a dry promoter,
Wherein the hydrocarbon solvent is an aromatic hydrocarbon solvent and the acetate solvent is one selected from the group consisting of propylene glycol 1-methyl ether 2-acetate and butyl acetate or a mixture thereof.
The method according to claim 1,
Wherein the moisture-curable polyurethane resin is an MDI-based isocyanate.
delete delete delete delete Adding a wet dispersant and a flowable additive to the hydrocarbon-based solvent and mixing (step 1);
Adding a water absorbent and a moisture-curing polyurethane resin to the hydrocarbon-based solvent, mixing and then adding a polymer-coated aluminum paste and stirring (Step 2); And
(Step 3) mixing and mixing the mixture of step 1 and step 2, respectively, after mixing and mixing a moisture-curing polyurethane resin, a water absorbent, a drying promoter and butyl acetate,
The polymer-coated aluminum paste comprises 45 to 65% by weight of an aluminum-coated aluminum powder and 35 to 55% by weight of naphtha having a carbon atom number of 6 to 12 at a boiling point of 90 to 200 ° C,
Wherein the hydrocarbon solvent is an aromatic hydrocarbon solvent and the acetate solvent is one selected from the group consisting of propylene glycol 1-methyl ether 2-acetate and butyl acetate or a mixture thereof. .
delete 8. The method of claim 7,
Wherein the moisture-curing polyurethane resin is an MDI-based isocyanate.
delete A coated article coated with the corrosion-resistant paint composition for a metal according to claim 1 or 2.

Images