KR101583731B1 - Paint composition for steel structure having steel bridge, and method for painting of steel structure using this same - Google Patents

Abstract

The present invention relates to a paint composition for repairing and reinforcing a steel structure comprising a steel bridge, and a painting method of a steel structure using the same. The paint composition for repairing and reinforcing a steel structure comprising a steel bridge according to the present invention is produced by mixing: 100 parts by weight of a main material by mixing 30 to 50 wt% of a vinyl acetate copolymer, 10 to 20 wt% of zinc, 20 to 40 wt% of a diluent, and 10 to 15 wt% of an additive; and 40 to 60 parts by weight of a hardener by mixing 20 to 40 wt% of aliphatic, alicyclic, or aromatic isocyanate and 60 to 80 wt% of a diluent. In addition, the paint composition is used as a primer paint for priming steel so as to increase adhesion of the steel structure.

Description

TECHNICAL FIELD [0001] The present invention relates to a coating composition for repairing and reinforcing steel structures including steel bridges, and a steel structure coating method using the same.

The present invention relates to a coating composition for a steel material, and more particularly, to a coating composition for a steel material, which is coated with a primer coating on the surface of a steel structure such as a steel pipe bridge or a steel bridge overpass to improve the durability of the steel composition, By using the sacrificial anodic action, it is possible to delay the forced corrosion of the substrate and improve the water resistance, light resistance, ozone resistance, weather resistance and durability through the middle and top paint. And a steel material structure coating method using the same.

Steel products such as steel pipes and steel structures using the steel products are not only deteriorated in strength due to salt infiltration or water penetration, but also become durable due to corrosion, resulting in a decrease in service life. Particularly, bridges built on the beach are infiltrated with salt, resulting in serious durability deterioration.

In order to reduce the durability of such a steel structure, it is common to coat the surface of the steel structure.

Inorganic end-of-life paints, chlorinated rubber-based paints, and epoxy-based paints, which are currently widely used, are as follows.

1. Mineral zinc powder paint.

The following are known as anti-corrosive paints using zinc powder as the main rust inhibitor. Called zinc rich paint, which is made by putting a high concentration of zinc powder or zinc fine powder into a small amount of resin.

2. Chlorinated rubber-based paint.

Chlorinated rubber coatings, which are generally used in heavy-duty coatings, have a high drying speed, good interlayer adhesion, and are resistant to contamination and coastal environments. In particular, chlorinated rubber coatings are superior in transparency and oxygen permeability to other paints due to their excellent coating properties, which is advantageous for coating steel structures such as containers and ships.

3. Epoxy-based paint.

Epoxy-based anticorrosive coatings have widely used various polyamine compounds, especially aliphatic polyamine compounds, as curing agents for epoxy resins for room temperature curing.

Patent Document 1 (Patent No. 10-1269132) is a ceramic two-component type anticorrosive coating composition comprising a main component and a curing agent, which is patented by the applicant of the present invention. The main theme of the present invention is a ceramic composition comprising a) 2 to 6 functional groups, 30 to 60 parts by weight of a polymer alloy in which a phenol novolak type epoxy resin having a number average molecular weight of 600 to 600 and a bisphenol F type epoxy resin having 1 to 2 functional groups and an equivalent weight of 150 to 300 is mixed; b) 5 to 20 parts by weight of a multifunctional reactive diluent selected from butyl glycidyl ether, phenyl glycidyl ether, aliphatic glycidyl ether; c) 30 to 60 parts by weight of a ceramic filler selected from the group consisting of hydrofobic silica, aluminum oxide, magnesium oxide and zinc oxide, wherein the curing agent comprises: a) 10 to 25 parts by weight of an amine resin having an equivalent weight of 50 to 400; b) 5 to 15 parts by weight of an amide resin having an equivalent weight of 100 to 400; c) 3 to 10 parts by weight of a bisphenol F type epoxy resin having two functional groups and an equivalent weight of 150 to 300.

Registration No. 10-1269132

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to improve the durability of a steel structure such as a steel pipe by improving its durability and to delay the forced corrosion of the steel material by using a sacrificial anode action of zinc, The present invention provides a coating composition for repairing and reinforcing a steel structure including a steel bridge that improves ozone resistance, weather resistance, and durability, and a steel structure coating method using the same.

A steel structure construction method using a coating composition for repairing and reinforcing steel structures including a steel bridge according to the present invention includes a first step of arranging a surface of a steel structure; A second step of coating the primer layer on the surface of the steel after the first step and then curing the primer layer; A third step of coating the intermediate coating on the surface of the primer layer formed through the second step and then forming the intermediate layer through curing; And a fourth step of applying a phase change coating material to the surface of the intermediate layer formed through the third step and curing the phase change layer to form an upper phase layer, wherein the second step is a step of applying a vinyl acetate copolymer in an amount of 30 to 50 wt% 20 to 40% by weight of an aliphatic, alicyclic or aromatic isocyanate with respect to 100 parts by weight of a mixture of 10 to 20% by weight of zinc, 20 to 40% by weight of a diluent, and 10 to 15% The primer layer is applied by applying a primer coating mixed with 40 to 60 parts by weight of a curing agent consisting of 60 to 80% by weight of a diluent,

The third step may include 10 to 30 wt% of a phenol novolak epoxy resin, 10 to 30 wt% of a bisphenol A type epoxy resin, 5 to 10 wt% of a polyfunctional reactive diluent, 40 to 60% by weight of an amine resin and 20 to 40% by weight of an amide resin, based on 100 parts by weight of a mixture of 30 to 60% by weight of a filler and 5 to 10% by weight of an additive of at least one of an antireflective agent, % Of epoxy resin and 10 to 20% by weight of bisphenol A type epoxy is mixed with 20 to 50 parts by weight of a curing agent to form a middle layer,

In the fourth step, 100 parts by weight of a mixture of 50 to 70% by weight of an acrylic polyol, 15 to 35% by weight of a diluent and 10 to 20% by weight of an additive, And 20 to 50 parts by weight of an alicyclic isocyanate curing agent having a solids content of 50 to 50% by weight and a solid content of 30 to 70% by weight, is applied to the upper layer.

According to the paint composition for repairing and reinforcing steel structure including a steel bridge according to the present invention and the steel structure coating method using the same, a primer paint is applied to the surface of a steel structure such as a steel pipe bridge or a steel bridge overpass, It improves the durability of the structure, delays the forced corrosion of the substrate by using the sacrificial anode action of zinc (Zinc), improves the waterproof, waterproof, light resistance, ozone resistance, weatherability and durability through the middle and top paint It is possible to maintain the initial coating state even when it is cured, thereby extending the life of the steel structure.

A coating composition for repairing and reinforcing steel structures including a steel bridge according to the present invention is characterized by comprising a primer coating which is applied to the surface of a steel material to form a primer layer, a middle road for coating the surface of the primer layer, And an upper paint for coating the upper layer.

The primer coating is a mixture of a base and a curing agent.

The subject is a mixture of 30-50 wt% vinyl chloride-vinyl alcohol-vinyl acetate copolymer, 10-20 wt% zinc, 20-40 wt% diluent, and 10-15 wt% additive .

The vinyl acetate copolymer has a strong adhesive property so that it is not peeled from the surface of the steel and is adhered with a strong adhesive force. Less than 30% by weight of the vinyl acetate copolymer has a weak adhesive force, and if it exceeds 50% by weight,

Zinc (10 ~ 20㎛) delays corrosion of steel structure by sacrificial anodic action. If it is out of the range of 10 ~ 20 weight%, corrosion retardation effect is weak and weakening of adhesion is given.

The diluent may be selected from the group consisting of xylene, toluene, methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), ethylacetate (EA), n-butylacetate (BA) CA (Cellosolve Acetate) Is mixed in the range of 20 to 40% by weight to control the physical properties of the materials, and when two or more are mixed, they are freely adjusted in the above-mentioned range.

The additive is at least one of a quencher having a particle size of 0.5 to 30 μm, a precipitation preventing agent used for preventing precipitation, a pigment, and a defoaming agent used for removing bubbles. The additive can be freely selected according to the characteristics (use) Silica, calcium carbonate, talc, and scorching can be selected, and the powdery material can use the above-mentioned particle size.

The curing agent is a mixture of 20 to 40% by weight of an aliphatic, alicyclic or aromatic isocyanate and 60 to 80% by weight of a diluent.

Isocyanate is excellent in stability and strength enhancement and hardenability due to crosslinking of materials.

The diluent may be the same material used in the subject.

The mixing ratio of the isocyanate and the diluent is for the function of the curing agent, and if the ratio is out of the range, the function of the curing agent is weak or there is not a large difference in effect.

The primer coating is formed by mixing 40 to 60 parts by weight of a curing agent with respect to 100 parts by weight of the above-mentioned composition, which is an optimum ratio for excellent adhesion and corrosion prevention.

The primer coating composition may be prepared by, for example, mixing a vinyl acetate copolymer, zinc, a diluent, and an additive in a stirrer, stirring the mixture at 60 to 70 ° C for 60 to 180 minutes to prepare a subject, and then mixing the isocyanate and the diluent at 60 to 60 ° C The mixture was stirred for 120 minutes and then cooled to a temperature of 75 to 85 ° C to prepare a curing agent. The thus prepared curing agent and the curing agent were stirred at room temperature to prepare a primer coating. The method for producing the primer coating according to the present invention is not limited to the one described above, and the method for producing the intermediate coating material and the top coating material may be the same as the method for producing the primer coating material.

The intermediate coating consists of a mixture of a base and a hardener.

The present invention relates to an epoxy resin composition comprising 10 to 30% by weight of a phenol novolak epoxy resin, 10 to 30% by weight of a bisphenol A type epoxy resin having 1 to 2 functional groups and an equivalent weight of 150 to 300, 5 to 10% by weight of the ash, 30 to 60% by weight of the ceramic filler, and 5 to 10% by weight of the additive.

The phenol novolac epoxy resin is a phenol novolac epoxy resin having 2 to 6 functional groups and an equivalent weight of 200 to 600, and is excellent in heat resistance, chemical resistance and adhesion.

 As the bisphenol A type epoxy resin, it is preferable to use bisphenol A type epoxy resin having 1 to 2 functional groups and 150 to 300 equivalents, and it is an epoxy resin prepared by polymerizing epichlorohydrin and bisphenol A, Of the hydroxyl groups and the hydrophobic hydrocarbon groups are regularly arranged.

The polyfunctional reactive diluent may be at least one of butyl glycidyl ether, phenyl glycidyl ether and aliphatic glycidyl ether, and when two or more thereof are used in combination, It is freely adjustable within the mixing range.

The multifunctional reactive diluent has the function of improving the impact resistance of the anticorrosive coating, controlling the strength thereof, and controlling the viscosity at the time of work. When the content of less than 5% by weight is mixed, the strength after curing becomes too strong. .

The ceramic filler is used as an inorganic material for improving chemical resistance, abrasion resistance, and the like. The ceramic filler may be at least one selected from the group consisting of hydrophobic silica, aluminum oxide, magnesium oxide, zinc oxide, It is possible to substitute other materials having equivalent functions, and when two or more are used, they are mixed in a free mixing ratio.

The ceramic filler preferably has a particle diameter of 10 to 40 mu m. If the particle diameter of the ceramic filler is less than 10 mu m, the flowability during coating is lowered and the workability is lowered. On the contrary, when the filler particle diameter is 40 mu m or more, problems may occur in appearance, flexibility and moisture absorption rate. If the content of the ceramic filler is less than 30% by weight, the coating of the present invention becomes too soft even after being cured to weaken the adhesion performance during crosscutting. On the other hand, if the content of the ceramic filler is more than 60% by weight, There is a problem that adhesion performance is decreased.

The additive is at least one selected from pigments, leveling agents, antifoaming agents, dispersants, and curing accelerators, and it is possible to use materials used in primer coatings such as silica, calcium carbonate, talc,

As the pigment, organic or inorganic pigments such as titanium dioxide (TiO2), carbon black (Carbon Black), phthalocyanine blue, diazo yellow and the like can be used.

As the leveling agent, a silicone type or a wax type may be used, but not limited thereto, and those commonly used in the art can be used.

The antifoaming agent may be anionic, cationic or nonionic. However, the antifoaming agent is not limited thereto, and a kind commonly used in the art may be used.

The dispersing agent may be anionic, cationic or nonionic, but is not limited thereto, and a species conventionally used in the art may be used.

Finally, the curing accelerator may be a tertiary amine system such as BDMA (benzol dimethyl amine), DMP30 {[0031] Tris (dimethyl aminomethyl) phenol}, but is not limited thereto and those commonly used in the art may be used have.

 The curing agent may be at least one of an amine resin having an equivalent weight of 50 to 300, an amide resin having an equivalent weight of 100 to 400, and a bisphenol A type epoxy resin having 1 to 2 functional groups and an equivalent weight of 150 to 300.

The intermediate coating material is obtained by mixing 20 to 50 parts by weight of a curing agent with respect to 100 parts by weight of the subject, which is an optimum ratio for excellent heat resistance and durability.

The top coat consists of a blend of a base and a curing agent.

The subject matter consists of a mixture of 50 to 70% by weight of an acrylic polyol, 15 to 35% by weight of a diluent and 10 to 20% by weight of an additive.

The acrylic polyol has a glass transition temperature (Tg) of -30 to 20 ° C., a solid content of 30 to 80% and an equivalent weight of 500 to 3,000. The diluent is the same as the diluent used in the primer coating, (Methyl ethyl ketone, MIBK), EA (Ethyl Acetate), BA (N-Butyl Acetate), CA (Cellosolve Acetate) ) Is used, and the additive is at least one selected from a fogging material, a leveling material, an anti-settling material, a pigment, a photocatalyst, and a dispersing material. The functional material used as the additive is the same as or similar to the material of the additive described in the primer coating, and all of the products used in the coating field can be used.

The curing agent is an alicyclic isocyanate having two or more functional groups and an isocyanate group content of 10 to 50% and diluted with a diluent to adjust the solid content to 30 to 70%. For example, isophorone diisocyanate (IPDI) Cyclohexylmethane diisocyanate (H12MDI) is used as a diluent (Xylene, Toluene, Methyl ethyl ketone, Methyl Isobutyl Ketone, MIBK) , EA (Ethyl Acetate), BA (N-Butyl Acetate), and CA (Cellosolve Acetate)] (the ratio of the diluent is 50 to 150 parts by weight based on 100 parts by weight).

The top coat paint is prepared by mixing 20 to 50 parts by weight of a curing agent with respect to 100 parts by weight of the subject, which is an optimum ratio for excellent heat resistance and durability.

<Examples>

In order to confirm the characteristics of the primer paint, the intermediate paint and the top paint applied in the present invention, the following samples were prepared and tested.

1. Primer coating.

Diluents of the subject and curing agent were mixed in the same weight ratios of xylene and toluene, respectively.

The additives were the same in the range of 10 wt% for the quencher, the precipitation inhibitor, the pigment and the defoamer.

A primer coating material (material mixture) was prepared with the composition of the above example, and then a sample (steel plate) of the same standard was painted with a predetermined thickness and tested.

※ Adhesion strength: ASTM D4541 - Test according to the test method "Standard Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers".

* Salt water resistance: Confirmation of rust by immersion in 50g / L Nacl solution.

2. Medium-duty paint.

The reactive diluent in the subject is butyl glycidyl ether.

The additive is used in the same ratio of pigment, leveling agent, antifoaming agent, dispersant and curing accelerator.

(Example 2-6) was applied to the surface of the primer coating material of Examples 1-5 after the intermediate coating material was prepared (mixing the materials) in the composition of the above examples, and the remaining primer of Example 2-1 and the like were not applied The test was carried out on a steel plate with a certain thickness.

※ Bending performance: KS F 4292

※ Impact performance: KS D 8502

※ Water Absorption Rate: ASTM D 570

※ Cold repeatability: KS D 8502

3. Upper paint.

The diluent of the base and hardener was mixed in the same ratio of xylene and toluene.

The additive material was a mixture of a fogging material, a leveling material, an anti-settling material, a pigment, a light reducing material and a dispersing material in the same weight ratio.

After the top coat paint was prepared (mixed material) in the composition of the above example, the paint was painted with a certain thickness in Test Example 2-6 in which the intermediate paint was painted.

The test results of the primer coating, the intermediate coating and the top coating paint according to the present invention were found to be excellent in all items.

The steel structure coating method according to the present invention is as follows.

1. Surface preparation of steel structures.

For example, in the case of steel bridges, corrosion occurs due to various causes such as aging and salt corrosion. In order to repair such a repair part, the maintenance part must be arranged first.

For example, in order to prevent the deterioration of adhesion between the coating layer and the steel, the corroded portion, the cracked portion and the peeled portion are removed and the foreign matter is removed.

2. Construction of primer layer.

The primer coating is preferably applied to the surface of the steel structure by coating (spraying, spraying, etc.) at a thickness of preferably 20 to 60 탆, followed by curing (natural curing is possible, The primer layer is applied.

The primer layer is adhered to the steel material and the intermediate layer with strong adhesive force to prevent peeling of the coating layer.

3. Construction of middle floors.

After completion of the primer layer through the previous step, the intermediate coating is applied preferably to a thickness of 100 to 200 탆, followed by curing (for example, 12 to 15 hours).

4. Construction of upper floors.

The coating layer is applied on the surface of the middle layer, and the coating layer is formed on the surface of the steel structure.

Claims (4)

Based on 100 parts by weight of a mixture consisting of 30 to 50% by weight of a vinyl acetate copolymer, 10 to 20% by weight of zinc, 20 to 40% by weight of a diluent and 10 to 15% by weight of an additive, Characterized in that 400 to 60 parts by weight of a curing agent composed of 20 to 40% by weight of an aliphatic, alicyclic or aromatic isocyanate and 60 to 80% by weight of a diluent is mixed and used as a primer coating for the purpose of increasing the adhesion of a steel material Wherein the steel structure comprises a steel bridge. 10 to 30% by weight of a phenol novolak epoxy resin, 10 to 30% by weight of a bisphenol A type epoxy resin, 5 to 10% by weight of a polyfunctional reactive diluent and 30 to 60% by weight of a ceramic filler % Of an amine resin, 20 to 40% by weight of an amine resin, 20 to 40% by weight of an amine resin, and 10 to 40% by weight of a bisphenol A type epoxy resin, based on 100 parts by weight of a mixture of an antioxidant, And 20 to 50 parts by weight of a curing agent consisting of 10 to 20% by weight of a mixture of epoxy and 10 to 20% by weight of a curing agent is mixed with a primer layer of a steel. Based on 100 parts by weight of a mixture of 50 to 70% by weight of an acrylic polyol, 15 to 35% by weight of a diluent and 10 to 20% by weight of an additive, the content of isocyanate groups is 10 to 50% And 20 to 50 parts by weight of a curing agent which is an alicyclic isocyanate controlled to 30 to 70% by weight, is used as an upper coating for forming a top layer on the surface of a steel material. Coating composition. A first step of arranging the surface of the steel structure;
A second step of coating the primer layer on the surface of the steel after the first step and then curing the primer layer;
A third step of coating the intermediate coating on the surface of the primer layer formed through the second step and then forming the intermediate layer through curing;
And a fourth step of forming an upper layer by applying an upper paint on the surface of the intermediate layer formed through the third step and curing the upper layer,
The second step is a step 100 in which a mixture of 30 to 50% by weight of a vinyl acetate copolymer, 10 to 20% by weight of zinc, 20 to 40% by weight of a diluent and 10 to 15% A primer layer is applied by applying a primer coating mixed with 20 to 40% by weight of an aliphatic, alicyclic or aromatic isocyanate and 40 to 60% by weight of a curing agent comprising a mixture of 60 to 80% by weight of a diluent,
The third step may include 10 to 30 wt% of a phenol novolak epoxy resin, 10 to 30 wt% of a bisphenol A type epoxy resin, 5 to 10 wt% of a polyfunctional reactive diluent, 40 to 60% by weight of an amine resin and 20 to 40% by weight of an amide resin, based on 100 parts by weight of a mixture of 30 to 60% by weight of a filler and 5 to 10% by weight of an additive of at least one of an antireflective agent, % Of epoxy resin and 10 to 20% by weight of bisphenol A type epoxy is mixed with 20 to 50 parts by weight of a curing agent to form a middle layer,
In the fourth step, 100 parts by weight of a mixture of 50 to 70% by weight of an acrylic polyol, 15 to 35% by weight of a diluent and 10 to 20% by weight of an additive, And 20 to 50 parts by weight of a curing agent which is alicyclic isocyanate controlled to have a solid content of 50 to 50% and a solid content of 30 to 70% by weight is applied to the top layer to construct a top layer. Coating method of steel structure using paint composition.