KR20090022787A - Surface coating method of concrete structure - Google Patents

Abstract

The present invention relates to a surface coating method for waterproofing, preventing corrosion and deterioration of a concrete structure, and more specifically, it can be applied where the concrete surface and the concrete surface in the wet state by using the ceramic cross-sectional repair material and ceramic coating material. In addition, the present invention relates to a surface coating method for waterproofing, preventing corrosion and deterioration of a concrete structure to provide an environmentally friendly surface suitable for drinking water standards after application.

Description

Method for coating the surface of concrete structural materials

The present invention relates to a surface coating method for waterproofing, preventing corrosion and deterioration of a concrete structure, and more specifically, it can be applied where the concrete surface and the concrete surface in the wet state by using the ceramic cross-sectional repair material and ceramic coating material. In addition, the present invention relates to a surface coating method for waterproofing, preventing corrosion and deterioration of a concrete structure to provide an environmentally friendly surface suitable for drinking water standards after application.

Recently, a deterioration of a concrete structure, known as a semi-permanent structure, is occurring in a complex manner, and a method of painting is widely adopted as a protective measure. The deterioration of concrete structures is caused by a combination of salt, alkali aggregate reaction, neutralization, and other east seas, resulting in cracking and dropping of concrete. Various coating systems have been applied to protect concrete from such deterioration. However, as it is found that deterioration occurs in a complex manner, paint and coating systems for complex deterioration are indispensable.

The deterioration factors of the concrete structure are as follows.

Chloride attack is a phenomenon in which steel in concrete is corroded by salt, causing cracking and dropping of concrete. As a countermeasure, paint should be applied to prevent deterioration of oxygen, water and salts from the environment that causes corrosion of reinforcing steel, and to follow crack cracking.

Alkali-aggregate reaction is an alkali component contained in cement and silica and water of aggregate reacts to water glass (Na ₂ H ₂ SiO ₄ ), which causes the water glass to expand and cause cracking and collapse of concrete. It is a phenomenon. The countermeasure to prevent this is to apply a paint having a function of blocking the intrusion of water from the external environment and a function of properly dissipating the water present in the concrete, and following the concrete crack.

Carbonation is the production of calcium hydroxide by hydration during the curing of cement used in concrete. Calcium hydroxide is strongly alkaline at pH 12-13 and reacts with carbon dioxide gas, which shows weak acidity in the atmosphere, to produce calcium carbonate. The pH of calcium carbonate is 8.5-10. This decrease in pH of the concrete, which shows strong alkalinity, is called neutralization. As the reinforcing steel in the concrete rusts, the volume expands and leads to cracking and dropping of the concrete. As a countermeasure, paint should be applied to block carbon dioxide, a degrading factor in the external environment.

Another degradation is the East Sea in the cold zone. The East Sea is a deterioration caused by the freezing and thawing of moisture in the pores in the concrete, and when there is no gap enough to absorb the volume expansion caused by the freezing of the water, the concrete cracks or falls off due to the expansion pressure. As a countermeasure, paints should be applied which are capable of blocking deterioration factors in the external environment and following cracks resulting from freezing and thawing.

Salts in sea salt particles or snow spray applied to the winter season adhere to the concrete structures that have already exhibited alkali aggregate reactions, and salts invaded from cracks, etc., promote corrosion of internal reinforcing rods, thereby rapidly deteriorating concrete. This phenomenon occurs easily in construction joints and joints, which are fragile parts in which the composition is unevenly distributed in the concrete structure.

In concrete, composite deterioration is an important factor in the extension of coating, the permeability of deterioration factor, and the release of water, compared to general deterioration. The follow-up to expansion and contraction of cracks also requires more than twice the repeated fatigue resistance than general deterioration. That is, elongation of 0.8 mm and 0.4 mm or more is required at room temperature (20 ° C.) and low temperature (-20 ° C.), respectively.

In general, the neutralizing salt prevention paints of concrete structures are mainly composed of metal powder and adhesives and ceramic anticorrosive paints.

Korean Registered Patent No. 484565 uses FDA-approved epoxy resin and ceramic filler to be coated for water preservation and hygiene safety measures. Non-toxic ceramic anticorrosive coating is disclosed that can contribute to the national hygiene safety. However, the non-toxic ceramic anticorrosive coating agent is deteriorated by ultraviolet rays by using an epoxy resin, which lowers the strength of the coating film and has a weak disadvantage in weather resistance.

In addition, Korean Patent No. 484565 discloses a waterproof and anticorrosion method of a concrete structure using aluminum powder together with a polyurethane resin or an epoxy resin. The aluminum powder used here is an anti-corrosive pigment that causes the passivation of the metal, but has an anticorrosive function, but has a problem in securing long-term durability due to its high price and thin coating thickness.

These conventional paints have good initial adhesiveness with concrete, but the deformation characteristics such as coefficient of thermal expansion, drying, shrinkage, etc. are significantly different from concrete, so that dropping occurs at the interface of concrete in the long run, resulting in lowered adhesive strength and long-term durability. It has a difficult disadvantage. These phenomena shorten the life span of the structure and seriously affect the safety of the structure, causing enormous losses to the national economy by causing environmental problems and transportation problems. have.

Accordingly, studies are being actively conducted on surface coating materials having excellent elongation of coating film, permeability of deterioration factor, and water release property in order to prevent composite deterioration in concrete.

In order to prevent the composite deterioration of concrete, the present inventors have studied the surface coating material having excellent weather resistance while securing the physical properties excellent in the elongation of the coating film, the permeability of the deterioration factor, and the water release property. The present invention has been completed.

Accordingly, an object of the present invention is to provide a surface coating method for waterproofing, anticorrosion and deterioration of a concrete structure which ensures excellent physical properties as well as excellent properties of elongation of the coating film, permeation deterioration of the deterioration factor and water release properties. To provide.

In the present invention

1) the step of filling the ceramic cross-section repair material to a thickness of 100 ~ 200㎛ using an epoxy-based sealer on the wet concrete surface;

2) coating a ceramic anti-corrosive coating material having excellent anti-degradation functions such as concrete salting or neutralization and adhesion between the sealer and the top coating material to 200 to 500 μm; And

3) coating the top coat material to 40 ~ 60㎛ using a variety of colors of silicone acrylic urethane paint;

It includes and provides a surface coating method for waterproofing, anticorrosion and deterioration of the concrete structure.

The cured coating film using polyisocyanate and methyl silicate as a silicone acrylic resin and a hardening agent in the subject of the ceramic cross section repair material, the ceramic anticorrosive coating material and the top coat coating material of the present invention was superior in the anticorrosive performance of the cured coating film of the conventional concrete coating material. In particular, it has excellent weather resistance and pollution prevention function, so maintenance free is possible. In addition, the paint of the present invention prepared using silicone acrylic resin and non-sulfur-modified polyisocyanate and methyl silicate as a curing agent is an environmentally friendly paint suitable for drinking water standards, which satisfies all the above properties and thus enables long-term protection of concrete structures. It could also contribute to protection.

The present invention relates to a surface coating method for waterproofing, anticorrosion and deterioration of a concrete structure having excellent durability by introducing a system coating method for concrete, comprising the following steps:

1) the step of filling the ceramic cross-section repair material to a thickness of 100 ~ 200㎛ using an epoxy-based sealer on the wet concrete surface;

2) coating a ceramic anti-corrosive coating material having excellent anti-degradation functions such as concrete salting or neutralization and adhesion between the sealer and the top coating material to 200 to 500 μm; And

3) coating the top coat material to 40 ~ 60㎛ using a variety of silicone acrylic urethane paint.

The coating method according to the present invention is not only to obtain a smooth concrete surface by sealing the damaged surface or the bent portion of the concrete surface with a ceramic cross-section repair material, but also to prevent the degradation and contamination such as preventing salt damage or neutralization of the ceramic coating material. Coating the surface.

In addition, the ceramic cross-section repairing material of step 1) is an epoxy-based sealer having excellent adhesion to wet concrete surfaces, and has a thickness of 100 to 200 μm. After coating the ceramic anticorrosive coating material having excellent adhesion with the coating material to 200 ~ 500㎛, the top coating material is coated with a silicone acrylic urethane paint of various colors to be 40 ~ 60㎛ gives a weather resistance and pollution prevention function.

The ceramic cross-section repair material uses a low viscosity, amorphous bisphenol F-type epoxy resin and melamine resin as a main material without containing an environmental hormone material, and a curing agent uses a mixture of a modified aromatic amine and aniline.

The ceramic coating material uses bisphenol F-type epoxy resin as the main material, and uses phenalkamine (Phenalkamine) having excellent low-temperature curing properties as a curing agent in winter, and prevents diffusion and permeation of water and water vapor, and improves the strength, abrasion resistance, and curing shrinkage of the coating film. Contains glass flakes with good suppression.

The top coat is made of silicone acrylic resin as the main material, and the sulfur-free polyisocyanate and silicate compound are used as a curing agent to impart weather resistance and antifouling function, and the colorant used herein is characterized by using an inorganic pigment having excellent weather resistance.

The technical configuration of the present invention will be described in detail as follows.

1. Ceramic Sectional Repair

The ceramic cross section repairing material of the present invention is used for smoothing the concrete surface at the same time filling a myriad of holes in the concrete surface layer with a landlocking material (putty material), and using a composition having excellent adhesion even when the concrete surface is somewhat wet. It was. The ceramic single-sided repair material composition can achieve excellent physical properties by using low viscosity, amorphous bisphenol F-type epoxy resin and melamine resin as the main agent, and using a mixture of modified aromatic amine and aniline as a curing agent without containing environmental hormone material. .

Ceramic cross-sectional repair material used in the present invention is (a) 60 to 80 parts by weight of bisphenol F-type epoxy resin (epoxy equivalent 180g / eq: YDF-162), 5 to 20 parts by weight of melamine resin (CYMEL H 216-8) and diluent A subject prepared by mixing 15 to 20 parts by weight; And (b) 10 to 20 parts by weight of modified aromatic amine (active hydrogen equivalent 110 g / eq: TH-452), 60 to 80 parts by weight of a mixture of modified aromatic amine and aniline (ANCAMINE 1482) and 10 to 20 parts by weight of a diluent Prepared curing agent; (a): (b) is prepared by mixing in a ratio of 5: 1 (equivalent ratio of epoxy and amine = 1: 1) by weight.

The bisphenol F-type epoxy resin used for the subject of the ceramic cross-section repair material which concerns on this invention used the epoxy equivalent about 175-185 g / eq (Kukdo Chemical, YDF-162). In addition, bisphenol F-type epoxy resins having an epoxy equivalent of 160 to 185 g / eq and a viscosity of about 700 to 7,000 cps may be used to control the viscosity of the coating composition of the present invention. The bisphenol F type epoxy resin contains 60 to 80 parts by weight of the total weight of the main body. Various components are mixed and used in the ceramic single-sided repair material composition, and it is a proper ratio to contain them, and when introduced in less than 60 parts by weight of the total weight, the absolute amount of the resin is insufficient, so that it can serve as a binder as a matrix. There is no crosslinking density when crosslinking with the curing agent, the physical properties such as acid resistance, alkali resistance is lowered. When it exceeds 80 parts by weight, the flowability is increased and the content of other components is insufficient, resulting in poor physical properties and workability.

Melamine resin (CYTEC Co., Ltd. CYMEL H 216-8) used in the subject of the ceramic cross-section repairing material according to the present invention, even if the impact and plasticity, heat resistance and somewhat wet conditions to give a sense of unity with the structure according to the shrinkage / expansion of the concrete structure 5 to 20 parts by weight of the total weight of the main body was introduced to provide adhesion and prevent cracking of concrete which may occur due to volume expansion by heat during the curing reaction. When it is introduced at less than 5 parts by weight of the total weight, the absolute amount of the resin is insufficient so that the above functions cannot be exhibited, and when it exceeds 20 parts by weight, miscibility and workability are poor.

The diluent used for the subject of the ceramic cross-section repair material by this invention can use reactive diluents, such as butyl glycidyl ether, phenyl glycidyl ether, and aliphatic glycidyl ether (C12-C14), and toluene, xylene, etc. Esters such as aromatic hydrocarbons, normal butyl acetate and ethylene glycol ethyl ether acetate, ketones such as methyl isobutyl ketone and methyl normal amyl ketone, alcohols such as isopropanol, normal butanol and isobutanol; And glycol ethers such as ethylene glycol monomethyl ether and propylene glycol monomethyl ether. The diluent contains 15 to 20 parts by weight of the total weight of the subject. In case of introducing less than 15 parts by weight of the total weight, the dilution effect is low, the viscosity is high and stirring is impossible, and when it exceeds 20 parts by weight, the viscosity of the main composition is excessively reduced, making it difficult to secure the coating film thickness and deterioration of adhesion. do.

As the modified aromatic amine used in the curing agent of the ceramic cross-section repair material according to the present invention, an active hydrogen equivalent of 110 ± 10 g / eq (Kukdo Chemical, TH-452) may be used. For example, TH-426, TH-427U, TH-428D, TH-430, TH-431, TH-432, TH-438, and TH-451 sold by Kukdo Chemical may be used. It is not limited only.

In addition, modified aromatic amines having an active hydrogen equivalent of 75 to 110 g / eq and a viscosity of about 200 to 23,000 cps may be used to control the viscosity of the coating composition of the present invention. The modified aromatic amine contains 10 to 20 parts by weight of the total weight of the curing agent. Various components are mixed and used in the ceramic cross-section repair material composition, and it is contained in such a suitable ratio, and when introduced in less than 10 parts by weight of the total weight, the pot life is short due to poor workability, and when it exceeds 20 parts by weight Pot life increases, but drying time is poor, workability is poor.

ANCAMINE 1482 (AIR PRODUCT) was used as the mixture of the modified aromatic amine and aniline used in the curing agent of the ceramic cross-section repair material according to the present invention. The mixture of the modified aromatic amine and aniline is contained 60 to 80 parts by weight of the total weight of the curing agent. Various components are mixed and used in the ceramic single-sided repair material composition, which is an appropriate ratio. When it is introduced at less than 60 parts by weight of the total weight, the pot life is good but the drying time is slow and when it exceeds 80 parts by weight. Drying time is shortened, but the pot life is short, workability is poor.

The diluent used in the curing agent of the ceramic cross-section repair material according to the present invention adjusts the viscosity to improve workability, adjust the film thickness and contribute to the storage stability of the paint. The diluent may be a reactive diluent such as butylglycidyl ether, phenylglycidyl ether and aliphatic glycidyl ether (C ₁₂ to C ₁₄ ), and aromatic hydrocarbons such as toluene and xylene, normal butyl acetate and ethylene glycol Esters such as ethyl ether acetate; Ketones such as methyl isobutyl ketone and methyl normal amyl ketone, alcohols such as isopropanol, normal butanol and isobutanol; And glycol ethers such as ethylene glycol monomethyl ether and propylene glycol monomethyl ether. The diluent contains 10 to 20 parts by weight of the total weight of the curing agent. When introduced at less than 10 parts by weight of the total weight, the dilution effect is low, the viscosity is high and stirring is impossible, and when it exceeds 20 parts by weight, the viscosity of the main composition is excessively reduced, making it difficult to secure the coating film thickness and the adhesion is lowered. do.

In the ceramic cross-section repair material according to the present invention, the main material and the curing agent are mixed at a weight ratio of 5: 1, and the equivalent ratio of the epoxy resin and the modified aromatic amine is preferably 1: 1. If one component is present in excess, excess unreacted material remains in the composition, resulting in slow drying and low crosslinking density, resulting in poor physical properties such as water resistance and weather resistance. The ceramic cross section repair material is epoxy-based sealer that has excellent adhesion to wet concrete surface and has a thickness of 100 ~ 200㎛.

In addition, in the present invention, the coupling agent used to improve the adhesion between the concrete surface layer and the ceramic cross-section repair material may use an epoxysilane compound having a molecular weight of about 220 to about 250. Examples of the epoxysilanes include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-glycidoxypropylmethyldimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β -(3,4-epoxycyclohexyl) ethyltrimethoxysilane, β- (3,4-epoxycyclohexyl) ethyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethylmethyldiethoxysilane, (gamma) -glycidoxy propyl triisopropenyl silane, (gamma)-glycidoxy propyl triimino oxysilane, etc. are mentioned.

These are used in 0.1 to 1.0% by weight of the total weight of the ceramic cross-section repair material.

2. Ceramic anticorrosive coating material

The ceramic anticorrosive coating material of the present invention is used for anti-degradation function such as preventing concrete salting or neutralization and for adhesion of ceramic cross-section repair material (sealer) and top coating material. Ceramic coating material uses bisphenol F-type epoxy resin as the main material, and uses phenalkamine, which is excellent in curing at low temperature in winter, as a curing agent, prevents the diffusion and permeation of water and water vapor, improves the strength and abrasion resistance of coating, and cures shrinkage. Excellent physical properties can be achieved, including glass flakes with excellent functionality.

Ceramic anticorrosive coating material used in the present invention is (a) bisphenol F-type epoxy resin (epoxy equivalent 180g / eq: YDF-162) 30 to 50 parts by weight, ceramic powder 25 to 35 parts by weight, glass flake (glass flake) 18 to A subject matter prepared by mixing 20 parts by weight, 2 to 5 parts by weight of additives and 5 to 10 parts by weight of a diluent; And (b) 27 to 30 parts by weight of phenalkamine (Cardolite lite-2001), 30 to 42 parts by weight of ceramics, 20 to 25 parts by weight of glass flakes, 10 to 12 parts by weight of additives and diluent 1 To 3 parts by weight of the curing agent; prepared by mixing in a ratio (a): (b) of the volume ratio of 1: 1 (equivalent ratio of epoxy and amine = 1: 1).

The bisphenol F-type epoxy resin used for the subject of the ceramic anticorrosive coating material of the present invention used an epoxy equivalent of about 175 to 185 g / eq (Kukdo Chemical, YDF-162). In addition, bisphenol F-type epoxy resins having an epoxy equivalent of 160 to 185 g / eq and a viscosity of about 700 to 7,000 cps may be used to control the viscosity of the coating composition of the present invention. Bisphenol F-type epoxy resin is contained 30 to 50 parts by weight of the total weight of the subject. Various components are mixed and used in the ceramic anticorrosive coating composition, which is a proper ratio, and when introduced in less than 30 parts by weight of the total weight, the absolute amount of the resin is insufficient, so that it may serve as a binder as a matrix. When crosslinking with the curing agent, the crosslinking density is lowered, and the physical properties such as acid resistance and alkali resistance are lowered. When it exceeds 50 parts by weight, the flowability is increased and the content and other components are insufficient, resulting in poor physical properties and workability. .

Ceramics used in the present invention may be used at least one ceramic powder of titanium oxide, talc, calcium carbonate, silica having a particle size distribution of 0.2 ~ 50㎛. In the present invention, 25 to 35 parts by weight of the total weight of the ceramics, including titanium oxide widely used as a white pigment is introduced. Ceramics are pigments in paints that provide color, hiding power, durability, mechanical strength, workability and gloss adjustment. When it is introduced at less than 25 parts by weight of the total weight, the mechanical strength is lowered. When it is more than 35 parts by weight, it is difficult to manufacture the paint by exceeding the critical pigment volume concentration, and the coating film properties are drastically lowered.

The glass flakes used in the present invention are microplate glass manufactured by Nippon Sheet Glass Co., Ltd., having a scale of 50-100 layers in the shape of scales and having a thickness of 5 ± 2 μm and a particle diameter of 45-300 μm. Microglas Glass Flake RCF-015 was introduced at 18 to 20 parts by weight of the total weight. The glass flakes are stacked in 50 to 100 layers and have anticorrosive function. In addition, since it is arranged in parallel with the base material, it can prevent the diffusion and permeation of water and water vapor, and improve the strength and abrasion resistance of the coating film to reduce the hardening shrinkage to prevent cracking and to be used at high temperatures with low thermal conductivity. When it introduces less than 18 weight part of total weight, the said function cannot be exhibited properly, and when it exceeds 20 weight part, a viscosity rises and workability becomes poor.

The additive used in the present invention is used for forming the coating film, improving the film properties and improving workability, and an antifoaming agent, a dispersant, a plasticizer, a thickener, an antisettling agent, an adhesion promoter, and the like are used. In the present invention, various additives, including antifoaming agents, were introduced at 2 to 5 parts by weight of the total weight. If the amount is less than 2 parts by weight of the total weight, problems occur in the coating and workability, and if it exceeds 5 parts by weight, cratering and deterioration of the coating occur.

The diluent used in the present invention adjusts the viscosity to improve workability, adjust the film thickness and contribute to the storage stability of the paint. Diluents may be reactive diluents such as butylglycidyl ether, phenylglycidyl ether and aliphatic glycidyl ether (C12 to C14), and aromatic hydrocarbons such as toluene and xylene, normal butyl acetate and ethylene glycol ethyl ether. Esters such as acetates; Ketones such as methyl isobutyl ketone and methyl normal amyl ketone, alcohols such as isopropanol, normal butanol and isobutanol; And glycol ethers such as ethylene glycol monomethyl ether and propylene glycol monomethyl ether. The diluent contains 5 to 10 parts by weight of the total weight. If the amount is less than 5 parts by weight of the total weight, the dilution effect is low, the viscosity is high and stirring is impossible. If it exceeds 10 parts by weight, the viscosity of the main composition is excessively reduced, making it difficult to secure the coating film thickness and the adhesion is lowered. do.

In the present invention, the amine used in the curing agent used Cardolite's Cardolite lite-2001 as phenalkamine having excellent low temperature curing properties in winter. Penalcamine contains 27 to 30 parts by weight of the total weight of the curing agent. It is contained in a suitable ratio for the ratio of equivalence ratio 1: 1 with the epoxy resin used in the subject of the ceramic anticorrosive coating composition, and if one component is present in excess, an unreacted excess of substance remains in the composition and dried. It becomes low and crosslinking density is low, and physical properties, such as water resistance and weather resistance, are bad. In addition, 30-42 weight part of ceramics, 20-25 weight part of glass flakes, 10-12 weight part of additives, and 1-3 weight part of diluents are used.

In the ceramic coating material according to the present invention, the main agent and the curing agent are mixed at a ratio of 1: 1 by volume, and in this case, the equivalent ratio of epoxy and phenalkamin is preferably 1: 1. The dry coating thickness of the ceramic coating material is best in the range of 200 to 500 µm. However, since the dry coating thickness that can be raised in one painting operation is about 100 to 250 µm, when the coating thickness is larger than the recommended dry coating thickness, the coating thickness is durable. Is excellent, but the work time is increased due to the increase in the number of painting operations, which causes problems in the field workability and productivity, and when it is smaller than the recommended range, the work time is shortened, but the dry film thickness is thin, so durability and corrosion resistance Falls. That is, because the coating film does not endure for a long time and wears out, there is a problem that the coating should be frequently performed.

3. Top coat coating material

The top coat coating material according to the present invention provides weather resistance and antifouling function by using a silicone acrylic resin as a theme and a non-sulfated polyisocyanate and a silicate compound as a curing agent, and the colorant used here is an inorganic pigment having excellent weather resistance. Excellent physical properties can be achieved.

The top coat material according to the present invention is (a) 10 to 30 parts by weight of a silicone monomer, 60 to 85 parts by weight of an acrylic or methacrylic monomer having an aliphatic group, 5 to 10 parts by weight of a methacryl monomer having a hydroxyl group, and a reaction initiator 1 To 3 parts by weight in a boiling point solvent for 3 to 5 hours, a silicone acrylic resin composition prepared by polymerization at 80 to 100 ℃ for 8 to 12 hours; And (b) a curing agent prepared by mixing a non-sulfur-modified polyisocyanate and methyl silicate in a weight ratio of 2: 1, and mixing (a) :( b) in a ratio of 5: 1 by weight, wherein (a): The equivalent ratio of NCO / OH in (b) is 1: 1.

The equivalent ratio (NCO / OH) of the hydroxyl group (OH) of the main silicone acrylic resin and the isocyanate (NCO) group of the non-sulfated polyisocyanate of the curing agent is 1: 1. The ratio of the content of the sulfurless-modified polyisocyanate and the silicate compound is 4: 1 (the weight ratio is the subject: curing agent = 5: 1).

The silicone acrylic resin composition of the present invention adjusts the glass transition temperature by using an acrylic or methacrylic monomer having an aliphatic group by introducing a silicone monomer to express the gloss and scratch resistance of the coating film and express high weather resistance. By introducing a silicone acrylic resin having a methacrylic monomer to increase the adhesiveness to increase the crosslinking density by crosslinking with a sulfur-free polyisocyanate to improve the drying rate, surface hardness, solvent resistance, etc. It is possible to give excellent weather resistance and smoothness and to impart non-pollution characteristics while maintaining an increase in the contact angle of surface energy and water.

To improve the stain resistance of paints, the surface of the coating is replaced with a hydrophilic component, which weakens the bonding force with lipophilic substances such as automobile exhaust, tire wear and soot, which are the main causes of contamination, and increases the cross-linking of the coating to increase the contamination. Not only are they difficult to penetrate, but they also need to be able to easily remove contaminants attached by rainwater. Therefore, although the alkali silicate compound containing an alkoxy group is widely used as a hydrophilic inorganic ceramic material of a coating film, methyl silicate is preferable.

Synthesis of the silicone acrylic resin of the present invention is 10 to 30 parts by weight of the silicone monomer, 60 to 85 parts by weight of the acrylic or methacrylic monomer having an aliphatic group, 5 to 10 parts by weight of the methacryl monomer having a hydroxyl group, and the reaction initiator 1 to 3 parts by weight was added dropwise to a medium boiling point solvent for 3 to 5 hours, followed by polymerization at a temperature of 80 to 100 ° C. for 8 to 12 hours, and a number average molecular weight of the resin composition of 16,000 to 20,000, a glass transition temperature of + 30 ° C., and a viscosity of 5 to 15 It provides a silicone acrylic resin composition having a cPs range and a solid content concentration of 50%.

The present invention also provides a non-polluting, highly weatherable two-component silicone acrylic / urethane top coat material composition containing the resin composition and a yellowing polyisocyanate as a curing agent and methyl silicate.

Hereinafter, the two-component silicone acrylic / urethane top coat material composition of the present invention will be described in detail.

The silicone acrylic resin composition according to the present invention is prepared by radically polymerizing various types of monomers having a vinyl double bond using a pyrolysis initiator. The radical polymerization is according to the solution polymerization method.

As the raw material used in the silicone acrylic resin composition, both acrylic acid esters and methacrylic acid esters may be used. Monomers having a vinyl double bond are used in the proportion of 10 to 30 parts by weight of the silicone-containing monomer, 60 to 85 parts by weight of the acrylic or methacrylic monomer having an aliphatic group, and 5 to 10 parts by weight of the methacryl monomer having the hydroxyl group.

As the silicone-containing monomer used in the present invention, compounds having the following structural formula may be used:

Examples of the acrylic or methacrylic monomer having an aliphatic group include normal butyl acrylate, 2-ethylhexyl acrylate, ethyl acrylate, normal butyl methacrylate, normal propyl methacrylate, methyl methacrylate, ethyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate, glycidyl methacrylate, lauryl methacrylate and isobornyl methacrylate, and the like. Examples of the methacryl monomer having a hydroxyl group include 2-hydride. Hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, and the like. One or more of these may be selected and used to adjust the glass transition temperature. Glass transition temperature is the range of 0-50 degreeC, Preferably it is 20-40 degreeC, but in this invention, the glass transition temperature was +30 degreeC.

The content of the silicone-containing monomer used in the present invention is preferably used to 10 to 30 parts by weight based on the solid content of the silicone acrylic resin. If the silicon content is too low, the weather resistance is poor, and if the relative high is too high, the price rise, the hardening of the coating film, storage stability may be poor.

Acrylic or methacrylic monomers used in the present invention is to adjust the glass transition temperature by appropriately adjusting the flexible monomer and the hard monomer. Their content is used to 60 to 85 parts by weight based on the solid content of the acrylic resin. These functions adjust the hardness of the coating film and give gloss and smoothness.

The methacryl-based monomer containing a hydroxyl group used in the present invention is used to add 2 to 10 parts by weight based on the solid content of the silicone acrylic resin, since the viscosity increase is severe when used in excess of them, preferably 5 to 10 parts by weight. Their function contributes to the enhancement of the hardness of the coating film and the adhesion with the workpiece.

Reaction initiators used in the present invention are radically polymerizable initiators such as benzoyl peroxide, tertiary butyl peroxy benzoate, tertiary butyl peroxy-2-ethyl hexanoate, tertiary millyl peroxy-2-ethyl hexanoate and Azobisisobutyronitrile etc. are mentioned. Such radically polymerizable initiators may be used alone or in combination of two or more thereof. The amount of the initiator is used to 1 to 3 parts by weight based on the total weight of the monomer composition, preferably 1 to 2 parts by weight. If the content of the radical initiator is too small, the viscosity and molecular weight is increased to generate a slip phenomenon, poor spray workability, if too large can cause a decrease in the coating properties due to excessive molecular weight decrease.

The solvent used in the present invention includes esters such as aromatic hydrocarbons such as toluene and xylene, normal butyl acetate and ethylene glycol ethyl ether acetate; Ketones such as methyl isobutyl ketone and methyl normal amyl ketone; Alcohols such as isopropanol, normal butanol and isobutanol; And glycol ethers such as ethylene glycol monomethyl ether and propylene glycol monomethyl ether; and these solvents may be used alone or in combination in consideration of the influence of the reaction temperature on the molecular weight and the final viscosity of the synthetic resin. In consideration of temperature, solubility parameter, evaporation rate, etc., it is preferable to synthesize | combine using the solvent whose boiling point is 100-160 degreeC, and using a thing whose boiling point is 110-150 degreeC suitably.

Synthesis method of the resin composition is polymerized for 8-12 hours at a temperature of 80 ~ 100 ℃ while adding and dropping the mixed solution containing the monomers and initiators listed above in a solvent solution in the reactor at a uniform rate for 3 to 5 hours. Proceed.

As described above, by inducing the reaction conditions stably, a silicone-containing acrylic resin composition having excellent glossiness, good smoothness and good scratch resistance can be obtained.

The sulfur-free polyisocyanate used as a curing agent in the present invention was used Desmodur N-3300 (NCO = 23%) of Bayer, Germany. As the content of the curing agent, the equivalent ratio of NCO / OH was used as 1/1 in consideration of the hydroxyl group of the silicone acrylic resin. If the hydroxyl group or the isocyanate group of the silicone acrylic resin does not participate in the crosslinking reaction, it does not form a dense crosslinking, resulting in deterioration of coating properties.

Methyl silicate, a hydrophilic inorganic ceramic material used in the curing agent in the present invention, used MS-57 from Mitsubishi chemical. The amount of methyl silicate used is preferably 10 to 25 parts by weight of the total weight of the curing agent, that is, 2 to 5% by weight of the total weight of the top coat material. When introduced to less than 2 parts by weight of the total weight of the top coat material, the anti-fouling function is lowered, and when it exceeds 5 parts by weight, not only the price increases but also the compatibility of the paint is poor, it is difficult to produce a transparent paint.

Hereinafter, the present invention will be described in detail through Examples and Comparative Examples, but the following Examples do not limit the scope of the present invention.

[Example 1-3 and Comparative Example 1]

In a four-necked flask equipped with a thermometer, a condenser, a dropping funnel and a stirrer, 140 g of xylene and 60 g of normal butanol were added thereto, and the temperature was increased to 90 ° C. while being replaced with nitrogen gas and stirring. While keeping the temperature of the solvent constant, a mixed solution of 4 g of azobisisobutyronitrile was added dropwise at a uniform rate over a period of 3 to 5 hours with the monomer and the initiator of the composition shown in Table 1 below. After completion of the dropwise addition, the mixture was further aged for 3 hours, and then 0.5 g of azobisisobutyronitrile was dissolved in 50 g of xylene as a post-initiator, added dropwise over 30 minutes, and stirred for 3 hours to remove unreacted monomers. Then, 86.8 g of xylene and 58.7 g of normal butanol were added thereto to dilute to obtain silicone acrylic resins of Examples 1 to 3 and Comparative Example 1 having a glass transition temperature of 30 ° C. and a solid content of 50%.

Test Example 1 Evaluation of Physical Properties of Coating Film

In order to examine the characteristics of the coating film formed from the composition comprising the silicone acrylic resin of Examples 1 to 3 and Comparative Example 1 Bayer Co. Desmodur N-3300 is a sulfur-free polyisocyanate with a silicone acrylic resin and a curing agent as shown in Table 2 below To prepare a silicone acrylic / urethane white paint was prepared by the equivalent ratio of NCO / OH to 1/1.

Coating performance test specimens were prepared as follows.

First, after arranging the surface of the concrete surface, paint the ceramic cross section repair material (sealer) with a spatula at 150㎛ dry film thickness (DFT) and let it dry naturally for 1 day, and then coat the ceramic coating material with 400 ~ 500㎛ coating twice. Sprayed to a thickness and dried. After 1 day of natural drying, the top coating material prepared by the above formulation was sprayed with DFT 50㎛ for 7 days after the natural drying to obtain a test coating film was investigated the coating performance.

<Evaluation Method>

Coating performance test was evaluated according to the general coating properties evaluation method as follows, the results are shown in Table 3 below.

1. Water permeability, moisture permeability, neutralization depth, chloride permeability, crack responsiveness, adhesion strength test: The above tests were evaluated according to the test method of concrete protective coating material of KS F 4936.

2. Oxygen Permeability Test: Oxygen permeability test evaluated the oxygen permeability according to the gas permeability test method of the plastic film and sheet of KS A 1027.

3. Solvent resistance test: The solvent resistance observed the appearance of the coating film peeling off with the number of times that the methyl ethyl ketone (MEK) was sufficiently immersed in the cloth, and then pressed on the coating film.

4. Accelerated Weathering Test: The accelerated weathering test is conducted in 1,000, 2,000, and 3,000 hours using a SWO (sunshine weather-meter) (atlas electric devices Co., Ci65A type) according to the accelerated weathering test method of paint of KS M 5000-3231. Gloss preservation value and color difference were evaluated.

(1) Gloss Preservation Value Measurement

Gloss retention value was calculated by the following equation (1) using a Glossmeter (Pacific Scientific Co., Glossgard Type II).

(2) color difference measurement

Color difference expresses the difference between two colors from visual to numerical concept. In other words, the geometric distance of two colors from the color space coordinates is displayed numerically. Spectro Color Meter (Dippon Denshoku Kogyo Co., SZ-∑ 80 type), which is a diffuse reflectance measuring device, was measured and the color difference was calculated by Equation 2 below.

Where L = Hunter color indicator

              a, b = chromaticity coefficients of the Hunter colorimeter

5. Accelerated fouling test: Accelerated fouling was sprayed on a specimen of carbon black dispersed in water and a solvent (mineral spirit) at 20%, and then immersed and dried at 80 ± 2 ° C. for 5 hours, and then washed with water and rubbed.

(1) water washability

The state remaining after the carbon-washed surface was naturally washed off by flowing water was judged visually.

(2) rub

When the surface of the coating film was wiped off with gauze or toilet paper, the degree of wiping off the surface was visually determined.

6. Drinking Water Dissolution Test: According to KS D 8502's drinking water dissolution test for liquid epoxy resin coating and coating method, it was suitable for all items as shown in Table 3 below.

Claims (12)

In the system anticorrosive method of ceramic cross section repairing material and ceramic anticorrosive coating and top coat coating material used for surface coating method for waterproofing, anticorrosion and deterioration of concrete structure 1) the step of filling the ceramic cross-section repair material to 100 ~ 200㎛ thickness using an epoxy-based sealer on the wet concrete surface; 2) coating the ceramic coating material to 200 ~ 500㎛; And 3) coating the top coat material to 40 ~ 60㎛ using a silicone acrylic urethane paint; Surface coating method of the concrete structure comprising a. According to claim 1, wherein the ceramic cross-section repair material used in step 1) (a) 60 to 80 parts by weight of bisphenol F type epoxy resin, 5 to 20 parts by weight of melamine resin, and 15 to 20 parts by weight of a diluent; And (b) 10 to 20 parts by weight of modified aromatic amine, 60 to 80 parts by weight of a mixture of modified aromatic amines and aniline, and 10 to 20 parts by weight of a diluent; Method for coating the surface of the concrete structure, characterized in that prepared by mixing so that the ratio of (a): (b) is 5: 1 by weight. The method of claim 2, wherein the ceramic cross-section repairing material is an epoxy resin and a modified aromatic amine in an equivalent ratio of 1: 1. The method of claim 1, wherein the ceramic anticorrosive coating material used in step 2) (a) 30 to 50 parts by weight of bisphenol F-type epoxy resin, 25 to 35 parts by weight of ceramic powder, 18 to 20 parts by weight of glass flake, 2 to 5 parts by weight of additives and 5 to 10 parts by weight of diluent ; And (b) 27 to 30 parts by weight of phenalkamine, 30 to 42 parts by weight of ceramics, 20 to 25 parts by weight of glass flakes, 10 to 12 parts by weight of additives, and 1 to 3 parts by weight of a diluent ; The surface coating method of the concrete structure, characterized in that it was prepared by mixing so that the ratio (a): (b) in the ratio of 1: 1. The method of claim 4, wherein the ceramic anticorrosive coating material is a mixture of an epoxy resin and a penalkamine equivalent ratio of 1: 1. According to claim 1, wherein the top coating material used in step 3) (a) 10 to 30 parts by weight of a silicone monomer, 60 to 85 parts by weight of an acrylic or methacrylic monomer having an aliphatic group, 5 to 10 parts by weight of a methacryl monomer having a hydroxyl group, and 1 to 3 parts by weight of a reaction initiator as a medium boiling point solvent Silicone acrylic resin composition prepared by polymerization for 8 to 12 hours at 80 ~ 100 ℃ while dropping for 3 to 5 hours; And (b) a curing agent prepared by mixing a sulfur-free polyisocyanate and methyl silicate in a weight ratio of 2: 1; (A): (b) is mixed in a ratio of 5: 1 by weight and (a): (b) the surface coating method of the concrete structure, characterized in that the equivalent ratio of NCO / OH of 1: 1. According to claim 6, wherein the silicone acrylic resin composition of (a) has a number average molecular weight of 16,000 ~ 20,000, glass transition temperature of +30 ℃, has a viscosity range of 5 ~ 15 cPs and a solid content of 50% concrete Surface coating method of the structure. The method of claim 6, wherein the silicone monomer used in (a) is

Surface coating method of the concrete structure, characterized in that at least one selected from the group consisting of. The method of claim 6, wherein the acrylic or methacrylic monomer having an aliphatic group used in (a) is normal butyl acrylate, 2-ethylhexyl acrylate, ethyl acrylate, normal butyl methacrylate, normal propyl methacrylate , Methyl methacrylate, ethyl methacrylate, 2-ethylhexyl methacrylate, octyl methacrylate, glycidyl methacrylate, lauryl methacrylate and isobornyl methacrylate Surface coating method of the concrete structure, characterized in that. The group according to claim 6, wherein the methacryl-based monomer having a hydroxyl group used in (a) is a group consisting of 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate and 4-hydroxybutyl methacrylate. Surface coating method of the concrete structure, characterized in that at least one selected from. The reaction initiator according to claim 6, wherein the reaction initiator used in (a) is benzoyl peroxide, tertiary butyl peroxy benzoate, tertiary butyl peroxy-2-ethyl hexanoate, tertiary millyl peroxy-2-ethyl hexa Surface coating method of the concrete structure, characterized in that at least one selected from the group consisting of noate and azobisisobutyronitrile. Concrete structure coated with the surface according to any one of claims 1 to 11.