KR102353907B1 - Painting method for long life of concrete structures with good neutralization recovery, UV protection and durability - Google Patents

Abstract

The present invention relates to a coating method for preventing neutralization of concrete and prolonging the lifespan of concrete structures with excellent UV resistance and durability. More specifically, the neutralization of concrete is prevented by using a neutralization inhibitor to react with lime components of concrete to form calcium silicate hydrate (C-S-H) crystals. By applying a water-based paint composition with UV-blocking performance to the outer surface of a concrete structure, which is a target, it is possible to improve adhesion and performance such as UV-blocking properties, weather resistance, and durability, and at the same time, improve heat-shielding performance.

Description

Painting method for long life of concrete structures with excellent UV resistance and durability, as well as prevention of neutralization of concrete {Painting method for long life of concrete structures with good neutralization recovery, UV protection and durability}

The present invention relates to a coating method for preventing the neutralization of concrete and increasing the lifespan of a concrete structure having excellent UV resistance and durability. CSH) prevents the neutralization of concrete by forming crystals, and applies a water-based paint composition with UV protection to the outer surface of the target concrete structure to improve performance and adhesion such as UV protection, weather resistance, durability, etc., and heat shielding performance It relates to a painting method of a concrete structure that can achieve a longer lifespan of a concrete structure by improving it.

Reinforced concrete structures deteriorate due to salt damage, neutralization, alkali aggregate reaction, and chemical corrosion, as well as corrosion and expansion of steel materials due to infiltration of water after construction. If the deterioration and cracking of these structures continue, there is a risk of eventually leading to the collapse of the structure, so it is necessary to continuously manage and repair them.

Neutralization, which can be said to be the main cause of concrete deterioration, weakens CSH (calcium silicate hydrate) crystals and loses alkalinity by slowly discharging calcium hydroxide in concrete from the inside of the concrete through the penetration of water or carbon dioxide gas in the air. and neutralization proceeds. When the neutralization of the concrete progresses, the cracks are damaged and the gaps widen, and then corrosion occurs as the reinforcing bars are exposed between the gaps. and new cracks are induced, and the new cracks further accelerate neutralization and rapidly weaken the durability of the concrete structure. Therefore, if cracks or cracks in the concrete structure occur, it is necessary to carry out repair work in order to prevent rapid neutralization in the early stage.

On the other hand, outdoor structures such as the roof of an apartment or building are painted with a colored or colorless paint for the purpose of making the appearance beautiful, waterproofing, etc. These paints can be oil-based or water-based. Recently, many water-based paints are used to prevent environmental and civil complaints. In the case of such water-based paints, they are easily discolored by UV rays and harden and crack over time. Functions and performance as paints this is lowered

Accordingly, the water-based paints currently used do not have a long lifespan, so frequent repainting is required. Therefore, it is an important task to increase the durability and weather resistance of paints painted on outdoor concrete structures to extend their lifespan.

In the past, techniques for extending the lifespan by improving the weather resistance and water resistance of water-based paints have been proposed.

For example, Korean Patent Laid-Open Patent No. 10-2020-0043362 discloses a heat-shielding pigment, a white pigment, an acrylic binder resin, a diluent and other additives dissolved or dispersed in water, a water-based heat-shielding paint and a hollow pigment, a white pigment, an extender pigment, and an elastic binder resin. Disclosed is a two-coat type water-based heat-insulating waterproof paint for a roof or roof made of a water-based insulation paint obtained by dissolving or dispersing a , a diluent and other additives in water. In this technology, it is eco-friendly and excellent in workability by using a two-coat water-based heat-shielding waterproof paint for roof or roof, and it has excellent thermal insulation and insulation properties without deterioration of physical properties and durability in environments directly exposed to sunlight and climate change. indicate that it can be obtained.

In addition, Korean Patent Laid-Open Publication No. 10-2009-0112813 relates to a water-based ceramic paint composition having excellent heat-shielding properties to block heat at extremely high temperatures and excellent fire resistance to suppress ignition or harmful gas emission, and the heat-shielding paint The composition contains a mixture of white titanium oxide, white antimony dichromate, and white antimony trioxide fine particles that function as a heat reflection function, and white chromite (FeCr2O4), SiC as a component to minimize the internal transfer of absorbed heat Including a mixture of , SiO2-Al2O3, Na2·3SiO2/silicon dioxide = 55~95% by weight/5~45% by weight of mixture and tungsten carbide. Disclosed is a coating composition.

In addition, Korean Patent Laid-Open No. 10-2018-0029147 relates to a water-based heat-reflecting thermal insulation paint having excellent UV blocking performance. , acrylic emulsion, thermal insulation material, titanium powder, light calcium carbonate powder and auxiliary agents, and the top coat includes water, water-based fluororesin emulsion, silicone acrylic emulsion, nano oxide insulating particles, titanium powder, light calcium carbonate powder and Doedoe composition as an auxiliary agent, wherein the insulating material is any one selected from vacuum glass grains, borosilicate vacuum glass grains, vacuum glass fibers, or a mixture of one or more thereof, and the nano-oxide insulating particles are, nano silicon dioxide, rutile-based (金紅柯謹) Thermal nano titanium dioxide, nano zinc oxide, nano aluminum oxide, or any one selected from a mixture of one or more thereof, and the auxiliary agent is an antifoaming agent, a dispersing agent, a wetting agent, an oiling agent, a fungicide / disinfectant, a pH adjusting agent Disclosed is a set of water-based heat-reflecting thermal insulation paints with excellent UV blocking performance, characterized in that they are at least one selected from among , a coating film former, a viscosity modifier, and an anti-freeze agent. At the same time, the coating film has excellent stain resistance and long-term weather resistance, so it has excellent overall aesthetic effect, and as an environmentally friendly water-soluble emulsion paint, it is safe and free from contamination.

In addition, Korean Patent Laid-Open No. 10-2012-0032697 relates to a UV and IR blocking coating agent prepared using water as a solvent and a coating film using the same, wherein an organosilane compound containing aminosilane is dispersed in an acidic aqueous solution, hydrolyzed and An organic-inorganic hybrid type polysiloxane binder prepared by polycondensation provides a water-based UV and infrared simultaneous blocking coating agent comprising an infrared blocking agent and water. According to the present invention, by preparing a binder for the coating agent using an amino silane that is hydrophilic and can induce strong bonding of polysiloxane at the same time, the dispersibility of the blocking agent particles is excellent compared to the existing water-soluble polymer resin-based coating binder, while optically Disclosed is a coating film having excellent properties and high film hardness that can block ultraviolet and infrared rays at the same time.

However, the conventional techniques exemplified above are mainly related to techniques for improving heat shielding performance and thermal insulation performance, techniques for improving water resistance and durability to extend lifespan, and the structure itself by preventing and preventing neutralization of concrete structures There is a limitation in not being able to present a technology that can achieve long lifespan of concrete structures by improving performance such as weather resistance and durability and adhesion by improving the technology to strengthen the concrete structure and UV protection.

The present invention is to solve the above problems, and by using a neutralization inhibitor for the concrete structure as a conductor to react with the lime component of the concrete to form calcium silicate hydrate (CSH) crystals to prevent and prevent the neutralization of the concrete structure By applying a water-based paint composition with UV-blocking performance to the outer surface of the concrete structure, which is the target, to improve performance and adhesion such as UV-blocking properties, weather resistance, and durability, and at the same time improve heat-shielding performance, thereby prolonging the lifespan of concrete structures. We want to provide a method that can achieve this.

In order to achieve the above object, the present invention

(1) Treat the surface of the concrete structure with a reactive calcium silicate solution to react with the lime component of the existing concrete and cure it to form CSH (calcium silicate hydrate) crystals and calcium carbonate crystals to prevent neutralization of the existing concrete structure. the first step of strengthening;

(2) a second step of applying a water-based paint composition for blocking UV rays on the surface; includes,

In the first step, the reactive calcium silicate solution is characterized in that it is prepared by dissolving calcium hydroxide and silicate in water,

In the second step, the water-based paint composition for blocking UV rays is 10-25 parts by weight of acrylic resin, 10-30 parts by weight of fluorine-modified resin, 20-35 parts by weight of titanium dioxide, 1-10 parts by weight of mica, 10-25 parts by weight of calcium carbonate 1 to 10 parts by weight of diatomaceous earth, 1 to 10 parts by weight of lime, 1 to 10 parts by weight of butyrate, 1 to 10 parts by weight of diol compound, 0.1 to 5 parts by weight of UV stabilizer, 0.1 to 10 parts by weight of UV absorber and silico Containing 0.1 to 5.0 parts by weight of a nate-based liquid component, and 1 to 20 parts by weight of a ceramic component consisting of one or two or more selected from talc, clay, silica, and acid clay. We provide a coating method for long life.

In one embodiment of the present invention, in the first step, the reactive calcium silicate solution is obtained by dissolving 5 to 20% by weight of a mixture of calcium hydroxide and silicate in 80 to 95% by weight of water, and the calcium hydroxide and silicate The mixture is characterized by using a mixture such that each ratio is 20 to 80: 80 to 20 by weight.

In addition, in one embodiment of the present invention, the acrylic resin included in the aqueous coating composition for blocking ultraviolet rays is selected from methyl acrylate, n-butyl methacrylate, 2-ethylhexyl acrylate polymer and acrylic acid copolymer. It is characterized in that one type or a mixture of two or more types is used.

In addition, in one embodiment of the present invention, the fluorine-modified resin included in the water-based coating composition for blocking ultraviolet rays is a mixture of a fluororesin having a weight average molecular weight of 1000 to 50,000 and an acrylic urethane resin having a weight average molecular weight of 5,000 to 100,000. It is configured and the fluororesin and the acrylic urethane resin are 100: characterized in that using a mixture in a weight ratio of 100 to 150.

In addition, in one embodiment of the present invention, the UV stabilizer included in the aqueous paint composition for blocking UV rays is 10 to 20 parts by weight of SBR (Styrene-Butadiene rubber) rubber, 0.1 to 5 parts by weight of a hydroxyl acrylate monomer, Unsaturated polyester resin 15-30 parts by weight, gallic acid 0.1-5 parts by weight, metal cations 1-10 parts by weight, aluminum chloride 0.1-1.0 parts by weight, dispersant 0.5-5 parts by weight, and water 40-70 parts by weight. characterized in that

In addition, in one embodiment of the present invention, the siliconate-based liquid component included in the aqueous coating composition for blocking ultraviolet rays is potassium methylsiliconate in a weight ratio of 0.1 to 5, 3-iodo-2-propynyl-N-butyl It is characterized in that 0.1 to 5 weight ratio of carbamate, 0.1 to 10 weight ratio of epoxy-based binder resin, and 0.1 to 5 weight ratio of inorganic polymer containing fluorine (F) group are used.

In addition, in one embodiment of the present invention, the water-based paint composition for blocking ultraviolet rays is at least one additive selected from the group consisting of an antifoaming agent, a dispersing agent, an antioxidant, a surface tension reducing agent, a leveling agent, an adhesion promoter, an antibacterial agent, and an inorganic pigment. It is characterized in that it further comprises 0.1 to 5 parts by weight.

In addition, in one embodiment of the present invention, the water-based paint composition for blocking ultraviolet rays is at least one selected from the group consisting of dodecylphenol, benzyl alcohol, propylene glycol monomethylether, and mixtures thereof. 5 to 20 parts by weight of the reactive diluent is further included.

In addition, in one embodiment of the present invention, the water-based paint composition for blocking ultraviolet rays is applied to the construction target surface by using a painting, rolling, or spraying method and is then cured.

In addition, in one embodiment of the present invention, after the first step, the method may further include applying a waterproofing mortar to the surface of the concrete structure according to the state of the structure.

At this time, the waterproof mortar is prepared by mixing 20-50 wt% of fast-hardening cement, 30-60 wt% of Portland cement, 5-30 wt% of alpha-type hemihydrate gypsum, and 0.1-5.0 wt% of nitrite powder, and then added to the binder. The mortar composition prepared by mixing the filler and aggregate may be applied by mixing with water.

In addition, in one embodiment of the present invention, after the second step, it is characterized in that the acrylic urethane-based or siloxane-based water repellent is additionally coated.

According to the present invention, by applying or impregnating the reactive calcium silicate solution on the surface of the concrete structure, the calcium hydroxide solution and the silicate solution in the reactive calcium silicate solution react with the lime component (CaO) of the existing concrete structure to form calcium-silicate hydrate (CSH) ) Forms crystals inside the structure (especially the cracks) and gradually expands to fill the voids caused by cracks. It also acts to densely fill the voids of the cracks, and at the same time blocks water from contacting the regenerated CSH crystals and weakening them again. Therefore, the neutralization problem caused by the weakening of CSH crystals is alkalized due to the CSH crystallization reaction of calcium carbonate due to the regeneration of CSH and the formation of calcium carbonate, thus preventing neutralization. can be strengthened with

In addition, the UV-blocking paint composition used in the present invention has excellent waterproof and anti-corrosive properties for the concrete structure as a conductor, and also has excellent UV-blocking performance, excellent physical performance such as adhesion and durability, water repellency, It has the effect of improving strength, corrosion and acid resistance. In particular, it has excellent durability against ultraviolet rays, so the color of the exterior wall of an apartment or building does not discolor even after a long period of time, so it solves the problem of frequent repainting. Therefore, it is possible to reduce the maintenance cost, so there is an advantage that the economic feasibility can be improved.

Therefore, there is an effect that can dramatically extend the lifespan of concrete structures through the application of water-based paint for UV protection and prevention of neutralization of damaged or expected concrete structures.

Hereinafter, the present invention will be described with reference to preferred embodiments. In the following description of the present invention, if it is determined that a detailed description of a related well-known function or configuration may unnecessarily obscure the gist of the present invention, the detailed description thereof will be omitted.

The painting method for long life of the concrete structure according to the present invention is configured including the following process. in other words,

(1) Treat the surface of the concrete structure with a reactive calcium silicate solution to react with the lime component of the existing concrete and cure it to form CSH (calcium silicate hydrate) crystals and calcium carbonate crystals to prevent neutralization of the existing concrete structure. the first step of strengthening;

(2) a second step of applying a water-based paint composition for blocking UV rays on the surface; is comprised of

Hereinafter, each step will be described in detail.

1. Stage 1 - Concrete Reinforcement Stage (Prevent Neutralization)

Concrete reacts with water and the concrete component (lime component) to dissolve into a calcium hydroxide solution, and when the water evaporates from it, calcium carbonate is formed into hard crystals, which are not easily dissolved by acids or other solvents. Since silver is strongly alkaline, neutralization of the structure can be prevented.

That is, the lime component (CaO) and water in the concrete are eluted into the calcium hydroxide solution and weaken the concrete. structure can be regenerated.

At this time, in the C-S-H crystal, the calcium component is supplied from the lime component in the cement and calcium hydroxide input from the outside, but the S (silicon) component must be supplied separately, so the silicate compound is dissolved in water together with the calcium hydroxide and supplied.

The silicate compound is an anionic material consisting of a silicon atom and an oxygen atom, and is mainly an orthosilicate (SiO ₄ ^4- ), metasilicate (SiO ₃ ^2- ) and pyrosilicate (Si ₂ O ₇ ^6- ), etc. It is composed of a mixture of sodium salts or esters, which form silicate ions when dissolved in water.

In the present invention, in preparing the reactive calcium silicate solution, calcium hydroxide and a silicate compound are dissolved in water, and the ratio for dissolution with water is 80 to 95% by weight of water and 5 to 20% by weight of a mixture of calcium hydroxide and silicate. It is preferable to dissolve in a proportion of %.

The ratio of the mixture of water, calcium hydroxide, and silicate may vary depending on the density of concrete or the number of years of concrete.

For example, if the density of the concrete is high and the cracks are relatively small, the mixture of calcium hydroxide and silicate can be dissolved in 90 to 95% by weight of water at a ratio of 5 to 10% by weight. When the degree is relatively large, a mixture of calcium hydroxide and silicate dissolved in 80 to 90% by weight of water in a ratio of 10 to 20% by weight may be used.

In addition, in preparing the reactive calcium silicate solution in the present invention, in the mixture of calcium hydroxide and silicate, it is preferable to use a mixture such that each ratio is 20 to 80:80 to 20 by weight.

The reactive calcium silicate solution is formed in a transparent liquid phase because calcium hydroxide and silicate are completely dissolved, and it is preferable to dissolve it under sufficient stirring to form such a liquid phase.

In addition, the silicate solution is a component that is additionally added to induce CSH crystals by the reaction of calcium ions and silicate ions by dissolving the calcium carbonate remaining after the formation of CSH crystals in the initial stage, and 85 to 95 wt% of water It can be formed by dissolving silicate in a proportion of 5 to 15 wt%.

In the concrete structure, cracks occur in the concrete due to deterioration, etc. As time passes, the compressive strength of concrete and the tensile strength of rebar gradually decrease. If such a phenomenon occurs or is expected to occur through safety diagnosis and inspection, cracks in the concrete structure must be repaired to maintain the lifespan of the structure for a long time.

The present invention restores the physical properties of concrete to alkalinity by internally forming CSH crystals and calcium carbonate crystals in the pores by applying the reactive calcium silicate solution prepared above to the cracked part (or including the non-cracked part) of the concrete. At the same time, the re-neutralization can be delayed by making the pores dense to prevent the penetration of water and carbon dioxide gas.

The lime component (CaO) in the concrete cement reacts with water _{to form calcium hydroxide (Ca(OH) 2} ) and slowly reacts with the silicate component to form insoluble calcium silicate hydrate (CSH) crystals to make the structure more dense Contributes to strength development and bonding strength enhancement.

The neutralization and deterioration of the concrete structure occurs when external water penetrates into cracks and the like and weakens the pre-formed C-S-H crystals.

The present invention can solve the problem of neutralization caused by the weakening of C-S-H crystals by introducing a material capable of forming C-S-H crystals in reverse.

The reactive calcium silicate penetrates deep into the interior of the concrete along the cracks, and C-S-H crystals are regenerated by the reaction of calcium in the lime component on the concrete surface and calcium hydroxide and silicate injected from the outside. Since the C-S-H crystals are formed with the lime component on the concrete surface, strong crystals can be formed in the pores.

In addition, excess ions remaining without reacting with the lime component on the concrete surface in the penetrating reactive calcium silicate solution naturally form calcium carbonate in the pores according to the evaporation of water.

Therefore, C-S-H crystals and calcium carbonate crystals exist together in the pores to make the pores dense.

Due to this process, CSH crystals and calcium carbonate crystals are generated in the pores, which over time forms a harder and denser structure, prevents the penetration of external carbon dioxide gas and water, and also recovers alkalinity to solve the neutralization problem. be able to

Since the reactive silicate solution used in the present invention is in the same state as water, it can be naturally introduced into microcracks, and therefore, even if there is dust or foreign substances on the concrete surface, it is possible to work without removing them in pretreatment.

In the present invention, a surfactant may be additionally mixed and used for deep penetration into the concrete. The surfactant may be included in an amount of 0.01 to 2.0 parts by weight based on 100 parts by weight of the obtained reactive calcium silicate solution.

In addition, when the crack size is relatively large, it may be applied by mixing fine inorganic materials, for example, silica sand, calcium carbonate, alumina powder, etc. may be additionally included, and some reinforcing fibers, for example, carbon fiber, super micro Fiber, glass fiber, etc. may be mixed and used.

2. Step 2 - Applying water-based paint for UV protection

Then, after the surface of the concrete structure is strengthened through the neutralization prevention process by the first step process, the surface is protected by applying a water-based paint (paint) for blocking UV rays.

In the present invention, a paint that is applied to the outer surface of outdoor concrete structures such as apartments and buildings to improve UV-resistance properties (UV-blocking properties), has excellent performance and adhesion such as weather resistance and durability, and can also improve heat shielding performance. .

In the present invention, the ceramic paint (water-based paint composition for blocking ultraviolet rays) having the above-mentioned UV-blocking properties is 10-25 parts by weight of acrylic resin, 10-30 parts by weight of fluorine-modified resin, 20-35 parts by weight of titanium dioxide, 1-10 parts by weight of mica parts, calcium carbonate 10-25 parts by weight, diatomaceous earth 1-10 parts by weight, lime 1-10 parts by weight, butyrate 1-10 parts by weight, diol compound 1-10 parts by weight, UV stabilizer 0.1-5 parts by weight, UV absorber Containing 0.1 to 10 parts by weight and 0.1 to 5.0 parts by weight of a siliconate-based liquid component, and further comprising 1 to 20 parts by weight of a ceramic component consisting of one or two or more selected from talc, clay, silica, and acid clay characterized in that

In the present invention, the acrylic resin may be prepared by emulsion polymerization, and is preferably an anionic acrylic resin to which anion is imparted. Acrylic monomers that can be used in the preparation of the acrylic resin are methyl acrylate, ethyl acrylate, propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, n-amyl acrylate, isoamyl acrylate , n-hexyl acrylate, 2-ethylhexyl acrylate, hydroxymethyl acrylate, 2-hydroxyethyl acrylate, hydroxypropyl acrylate, lauryl acrylate, methyl methacrylate, ethyl methacrylate, propyl Methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-amyl methacrylate, isoamyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate , hydroxymethyl methacrylate, hydroxypropyl methacrylate, lauryl methacrylate, acrylic acid, methacrylic acid, methyl acrylic acid, ethyl acrylic acid, butyl acrylic acid, 2-ethyl hexyl acrylic acid, decyl acrylic acid, methyl methacrylic acid, Ethyl methacrylic acid, butyl methacrylic acid, 2-ethylhexyl methacrylic acid, decyl methacrylic acid and the like can be used.

Specifically, in the present invention, the acrylic resin is an acrylic acid polymer or copolymer, for example, one or two selected from methyl acrylate, n-butyl methacrylate, 2-ethylhexyl acrylate polymer and acrylic acid copolymer. A mixture of the above may be used.

In the present invention, it is preferable to use a fluoro-modified resin composed of a mixture of a fluororesin and an acrylic urethane resin.

The fluororesin is a vinylidene fluoride resin (PVdF, Poly-Vinyliden di-Fluoride), which is a thermoplastic, crystalline polymer containing two fluorine (F) molecules as shown in the following Chemical Formula 1 in the molecule, and vinylidene fluoride is the resin It has a very large molecular weight and excellent solvent resistance, so it has a stable structure that does not dissolve easily in solvents at room temperature.

Therefore, in the present invention, since the fluororesin is the main resin that determines the basic physical properties of the paint, such as weather resistance, UV protection, ozone resistance, and chemical properties, it can be used without separate changes, and has excellent color stability and durability even after long-term external exposure. It has characteristics that make it excellent.

In the present invention, it is preferable to use the fluororesin having a weight average molecular weight of 1,000 to 50,000.

In addition, the acrylic urethane resin is uniformly stirred at a ratio of 130 parts by weight of ethanol as a solvent and 12 to 13 parts by weight of a polyisocyanate curing agent (acrytan curing agent) based on 100 parts by weight of acrylic urethane based on acrylic polyol as a main ingredient. It is preferable to use an acrylic urethane resin formed by mixing, and more specifically, it is preferable to use an acrylic urethane resin having a weight average molecular weight of 5,000 to 100,000.

In the present invention, the fluororesin and the acrylic urethane resin constituting the fluorine-modified resin are preferably mixed in a weight ratio of 100: 100 to 150, respectively.

In the present invention, the titanium dioxide is used to improve UV protection, weather resistance and durability.

In the present invention, the mica functions to improve thermal insulation, thermal barrier properties and durability.

In the present invention, the calcium carbonate functions to improve heat insulation, thermal barrier properties, abrasion resistance and durability.

In the present invention, the diatomaceous earth functions to improve thermal insulation, anti-condensation properties and adhesion.

In the present invention, the lime functions to improve adhesion performance and durability.

In the present invention, the butyrate serves to stabilize the acrylic resin, and in the present invention, it is preferable to use 2,2,4-trimethyl-1,3-pentanediol diisobutyrate.

In the present invention, the diol compound serves to improve the dispersibility of the composition, and it is preferable to use ethylene glycol or propylene glycol.

In the present invention, the ultraviolet stabilizer serves to prevent or delay the decomposition of polymers constituting paints such as acrylic resins and fluorine-modified resins, and the ultraviolet stabilizer used in the present invention is SBR (Styrene-Butadiene rubber) rubber 10 to 20 parts by weight, hydroxyl acrylate monomer 0.1 to 5 parts by weight, unsaturated polyester resin 15 to 30 parts by weight, gallic acid 0.1 to 5 parts by weight, metal cation 1 to 10 parts by weight, aluminum chloride 0.1 to 1.0 parts by weight, dispersing agent 0.5 to 5 parts by weight and 40 to 70 weight ratio of water may be used.

In the present invention, the SBR rubber preferably uses a resin having a solid content of 50% or more in order to maintain elasticity. This serves to prevent corrosion on the surface and is dispersed in a solvent, and also serves to increase the effect of gallic acid by dispersing and dissolving the gallic acid in a solution state. As the solvent, an ethylene glycol-based dihydric alcohol may be used.

In addition, the hydroxyl acrylate monomer functions to assist in UV blocking performance. As the hydroxyl acrylate monomer, hydroxyl ethyl acrylate, hydroxyl propyl acrylate, hydroxyl ethylmethyl acrylate, and the like may be used.

The unsaturated polyester is formed by condensation polymerization of an acid and a glycol compound, for example, an acid value of 18 to 20 mg/KOH formed by the reaction of fumaric acid and diethylene glycol may be used. The unsaturated polyester serves to enhance the weather resistance of the paint.

The gallic acid is a phenol carboxylic acid obtained by acid or alkali hydrolysis of tannin, and is a compound having a molecular formula of C7H6O5·H2O, and serves to aid in UV blocking performance.

The metal cation serves to strengthen the bondability with the internal primary and secondary paints, and as a specific example, one or two selected from ^{Ca 2+} , Mg ²⁺ , Zn ²⁺ , Cu ²⁺ , Fe ^{2+ .} More than one species can be used.

The aluminum chloride is formed by the reaction of an acid and aluminum hydroxide, and serves to improve the chemical resistance of the paint and strengthen the UV resistance performance.

The dispersing agent is for uniformly dispersing the internal components in the liquid phase to exhibit uniform performance. In the present invention, any one selected from a nonionic polyoxyalkylene surfactant or an anionic polycarboxyl salt surfactant can be used

In the present invention, the ultraviolet absorber absorbs ultraviolet rays harmful to the polymer and releases it in the form of heat to protect the polymer, and the ultraviolet absorber used in the present invention is one selected from hydroxybenzophenone and hydroxybenzotriazole. More than one species can be used.

In the present invention, the ceramic component serves to improve abrasion resistance and weather resistance, and one or two or more types selected from talc, clay, silica, and acid clay may be used.

In addition, in the present invention, the siliconate-based liquid component is potassium methylsiliconate 0.1 to 5 weight ratio, 3-iodo-2-propynyl-N-butyl carbamate 0.1 to 5 weight ratio, epoxy-based binder resin 0.1 to 10 weight ratio, and It is constituted by including a fluorine (F) group-containing inorganic polymer in a ratio of 0.1 to 5 weight ratio.

In the present invention, the potassium methylsiliconate serves to penetrate the surface reinforcing component of the paint composition according to the present invention into the concrete structure and at the same time to increase water repellency. In the present invention, the potassium methylsiliconate is preferably included in the range of 0.1 to 5 weight ratio in the siliconate-based coating composition. When the content of potassium methylsiliconate is less than 0.1 weight ratio, the surface strengthening effect and water repellency effect are insignificant, and when it exceeds 5 weight ratio, compatibility may be a problem. In the present invention, it is more preferable to use the potassium methylsiliconate having a solid content of 30 to 40% by weight and a pH of 12 to 14.

In addition, in the present invention, when the 3-iodo-2-propynyl-N-butyl carbamate is used in the coating composition according to the present invention, various harmful components of concrete are prevented from leaching to the outside, thereby causing environmental pollution. has a preventive effect. In the present invention, the 3-iodo-2-propynyl-N-butyl carbamate is preferably included in the range of 0.1 to 5 weight ratio in the siliconate-based liquid component. If the content of 3-iodo-2-propynyl-N-butyl carbamate is less than 0.1 weight ratio, the effect of preventing external elution of various harmful components of concrete is reduced, and if it exceeds 5 weight ratio, compatibility may be a problem. .

In addition, in the present invention, the epoxy-based binder resin serves to enhance the bonding force between each component of the composition and to increase the mechanical strength and watertightness of the inside of the concrete.

In the present invention, it is preferable to use the epoxy-based resin, and the content thereof is preferably included in the range of 0.1 to 10 weight ratio in the siliconate-based liquid component.

In addition, in the present invention, the inorganic polymer containing the fluorine (F) group serves to prevent corrosion of concrete by acid by enhancing acid resistance when the surface is exposed to acidic conditions after the coating composition according to the present invention is applied. do In the present invention, the inorganic polymer containing the fluorine (F) group is preferably composed of a mixture of aluminosilicate and fluoro alkali silicate in a weight ratio of 50 to 65:35 to 50. When the content of the aluminosilicate is less than the above range, there is a problem of a decrease in strength, and when the content of the aluminosilicate exceeds the above range, cracks may occur due to dryness of the paint.

In the present invention, the inorganic polymer containing the fluorine (F) group is preferably included in the silicone liquid component in a weight ratio of 0.1 to 5. If the content is less than 0.1 weight ratio, the effect of strengthening the acid resistance is insignificant, and if it exceeds 5 weight ratio, compatibility may be a problem.

The water-based paint composition for blocking UV rays according to the present invention may contain 0.1 to 5 parts by weight of at least one additive selected from the group consisting of an antifoaming agent, a dispersing agent, an antioxidant, a surface tension reducing agent, a leveling agent, an adhesion promoter, an antibacterial agent, and an inorganic pigment. may include

In addition, the aqueous paint composition for blocking UV rays according to the present invention is a non-reactive diluent 5 to 20 selected from the group consisting of dodecylphenol, benzyl alcohol, propylene glycol monomethylether, and mixtures thereof. It may be configured to further include parts by weight.

The water-based paint composition for UV protection obtained with the above composition can be used by mixing an appropriate amount of water, and the construction can be completed by applying it to the surface of the target structure using a method such as painting, rolling, or spraying and curing it.

The water-based paint composition for blocking UV rays according to the present invention has excellent effects such as UV resistance properties, durability, weather resistance, surface strength and water resistance reinforcement with only one application. It is preferable to do In the present invention, the water-based paint composition for UV protection* ^{is preferably applied at 20 to 1000 g/m 2} and the curing thickness is preferably 50 μm to 5 mm.

At this time, painting, rolling or spraying can be used to apply the UV-blocking acrylic reel paint composition to the construction target surface. Drying and curing is carried out for 6 hours, usually 24 hours in winter.

In addition, in the present invention, since the paint itself has a certain degree of rust prevention function, it can exhibit rust prevention properties without using a separate primer. it is preferable

As the primer used in the present invention, a rubber latex-based rust converter can be used, and it is preferable to use a rust converter that does not contain an organic solvent.

In addition, in the present invention, a water-repellent coating agent may be additionally coated after applying the water-based paint composition for blocking UV rays, and an acrylic urethane-based or siloxane-based water-repellent agent may be used as the water-repellent coating agent.

Above, a method capable of extending the life of a concrete structure by strengthening the surface of the concrete structure according to the present invention as a method of preventing and preventing neutralization, and then increasing durability by reinforcing UV-resistant performance has been described in detail. Hereinafter, examples will be described in detail with a focus on a method for enhancing UV resistance performance by using an aqueous coating composition for blocking UV rays. However, the scope of the present invention is not limited by the following examples.

[Example]

Example 1

20 parts by weight of the methyl acrylate polymer, 20 parts by weight of a fluoro-modified resin (a 100:100 mixture of a fluororesin (weight average molecular weight about 25,000) and an acrylic urethane resin (about 50,000 weight average molecular weight)), 25 parts by weight of titanium dioxide, mica 5 parts by weight, 15 parts by weight of calcium carbonate, 5 parts by weight of diatomaceous earth, 5 parts by weight of lime, 5 parts by weight of butyrate (2,2,4-trimethyl-1,3-pentanediol diisobutyrate), diol (ethylene glycol) 5 parts by weight, 2.5 parts by weight of a UV stabilizer, 2.5 parts by weight of a UV absorber (hydroxybenzophenone), and 2.5 parts by weight of a siliconate-based liquid component were mixed, and 10 parts by weight of talc was mixed to obtain a coating composition.

At this time, the UV stabilizer is SBR rubber (15 weight ratio), unsaturated polyester resin (20 weight ratio), hydroxyl acrylate monomer (1 weight ratio), metal cation (3 weight ratio), aluminum chloride (0.2 weight ratio) and dispersing agent (1 weight ratio) ) was mixed and water (60 weight ratio) was used, and as the siliconate-based liquid component, 1 weight ratio of potassium methylsiliconate and 2 weight ratio of 3-iodo-2-propynyl-N-butyl carbamate were used. , an epoxy binder resin 5 weight ratio and an inorganic polymer containing a fluorine (F) group (a mixture of aluminosilicate and fluoro alkali silicate in a weight ratio of 60:40) 1 weight ratio of silicanate-based liquid component obtained by mixing Thus, a coating composition was obtained.

Comparative Example 1

35 parts by weight of SBR latex resin, 50 parts by weight of ceramic component, 0.5 parts by weight of ultraviolet absorber (hydroxybenzophenone), and a certain amount of additives such as dispersant, shrinkage reducer, retarder, inorganic pigment, and filler are mixed to make the paint A composition was prepared.

Comparative Example 2

35 parts by weight of an acrylic latex resin, 50 parts by weight of a ceramic component, and 0.5 parts by weight of a UV absorber (hydroxybenzophenone) are mixed, and a certain amount of additives such as a dispersant, a shrinkage reducer, a retarder, an inorganic pigment, and a filler are mixed to make a paint A composition was prepared.

Comparative Example 3

30 parts by weight of a styrene monomer, 5 parts by weight of t-butylperoxybenzoide and 5 parts by weight of glycerin fatty acid ester are mixed, and 50 parts by weight of a ceramic component and 0.5 parts by weight of a UV absorber (hydroxybenzophenone) are mixed thereto, and a dispersant is mixed therein. , a shrinkage reducing agent, a retarder, an inorganic pigment, and a certain amount of additives such as a filler were mixed to prepare a paint composition.

1. Waterproof and anticorrosive performance test

Moisture permeability was measured by the method of ASTM F-1249 using the coating compositions according to Examples and Comparative Examples, and chloride ion penetration resistance and complex cycle corrosion resistance were evaluated according to the method of KSM ISO 11997-1. is shown in Table 1.

Moisture permeability (g/m ² , day) Chloride ion penetration resistance (coulombs) compound cycle
Corrosion resistance (600hr, %) Example 0.56 0.8 1.0 Comparative Example 1 6.9 15.0 6.8 Comparative Example 2 5.7 12.0 5.6 Comparative Example 3 7.5 16.0 7.2

From the results in Table 1, it can be seen that when the surface of a concrete structure is coated using the coating composition according to the present invention, waterproof and corrosion-resistant performance is very excellent, whereas in the case of the paint according to the comparative example, the performance is relatively poor.

2. Mechanical performance evaluation

1) Weatherability evaluation

400 hours were measured according to ASTM G 155.

2) Surface hardness evaluation

Pencil hardness was measured according to KS D 6711.

3) Water resistance evaluation

The time for continuous surface deformation (cracks, blisters, etc.) to occur in hot water at 90°C was measured.

Table 2 shows the evaluation results.

4) Adhesion evaluation

According to the test method of Test Method B of ASTM D3359, scrape the dried coating film 6 at 2 cm intervals with a knife to make 25 squares, adhere to the area with 3M transparent tape, and then proceed to 6 steps according to the degree of separation. Evaluate. The results are shown in Table 2.

5B: No peeling of the coating film at all

4B: Less than 5% of coating film peeling

3B: 5-15% of coating film peeling

2B: 15 to 35% of coating film peeling

1B: coating film peeling 35 to 65%

0B: 65% or more of coating film peeling

Weather resistance (white) surface hardness water resistance adherence Example △E10 4H 860hr 5B Comparative Example 1 △E17 2H 500hr 4B Comparative Example 2 △E15 3H 650hr 3B Comparative Example 3 △E14 3H 720hr 4B

As shown in Table 2, when the surface of the concrete structure was coated using the coating composition according to the present invention, it can be confirmed that the weather resistance, surface hardness, and water resistance are remarkably excellent and the adhesion performance is excellent compared to the case of the comparative example.

3. Coating film uniformity and surface crack evaluation

After 1 month after the formation of the coating film according to the above Examples and Comparative Examples, the uniformity of the coating film and the occurrence of surface cracks were visually evaluated by ◎ in the best case, ○ in the excellent case, △ in the normal case, and X in the case of poor. It was evaluated and the results are shown in Table 3 below.

film uniformity surface cracks Example ◎ ◎ Comparative Example 1 △ ○ Comparative Example 2 × × Comparative Example 3 × ×

From the results in Table 3, when the surface of a concrete structure is painted using the coating composition according to the present invention, the coating film uniformity is excellent and surface cracks do not occur, whereas in the case of the paint according to the comparative example, the coating film uniformity is relatively poor and the surface It was also confirmed that some cracks occurred.

4. UV blocking rate, infrared blocking rate characteristic evaluation

After forming the coating film according to the Examples and Comparative Examples, spectroscopic characteristics in the range of 250 nm to 2500 nm were measured using a UV-VIS-NIR spectrophotometer for the coating film, and the UV blocking rate and the infrared blocking rate were measured, and the results are shown in Table 4 it was

UV protection rate (%) Infrared blocking rate (%) Example 92.9 86.3 Comparative Example 1 85.0 80.1 Comparative Example 2 75.1 75.0 Comparative Example 3 70.5 76.2

From the results in Table 4, it can be seen that the coating composition according to the present invention exhibits superior performance compared to that of Comparative Example in UV blocking performance and IR blocking performance. Accordingly, it can be seen that the coating composition according to the present invention has excellent stability against ultraviolet rays and excellent heat shielding performance.

From the above experimental results, the coating composition according to the present invention has excellent UV blocking properties, heat shielding performance, waterproofing and corrosion resistance properties for the concrete structure as a conductor, as well as excellent adhesion and excellent physical properties such as durability, weather resistance and water resistance In addition, it can be confirmed that the uniformity of the coating film formation and the surface crack prevention performance are also very excellent.

As described above, the present specification has been disclosed with respect to a preferred embodiment of the present invention, and although specific terms are used, these are only used in a general sense to easily explain the technical content of the present invention and help the understanding of the present invention, It is not intended to limit the scope of the invention. It will be apparent to those of ordinary skill in the art to which the present invention pertains that other modifications based on the technical spirit of the present invention can be implemented in addition to the embodiments disclosed herein.

Claims (13)

(1) Treat the surface of the concrete structure with a reactive calcium silicate solution to react with the lime component of the existing concrete and cure it to form CSH (calcium silicate hydrate) crystals and calcium carbonate crystals to prevent neutralization of the existing concrete structure. the first step of strengthening;
(2) a second step of applying an aqueous paint composition for blocking ultraviolet rays to the surface; includes,
In the first step, the reactive calcium silicate solution is characterized in that it is prepared by dissolving calcium hydroxide and silicate in water,
In the second step, the water-based paint composition for UV blocking is 10-25 parts by weight of acrylic resin, 10-30 parts by weight of fluorine-modified resin, 20-35 parts by weight of titanium dioxide, 1-10 parts by weight of mica, 10-25 parts by weight of calcium carbonate 1 to 10 parts by weight of diatomaceous earth, 1 to 10 parts by weight of lime, 1 to 10 parts by weight of butyrate, 1 to 10 parts by weight of diol compound, 0.1 to 5 parts by weight of UV stabilizer, 0.1 to 10 parts by weight of UV absorber and silico Containing 0.1 to 5.0 parts by weight of a nate-based liquid component, and 1 to 20 parts by weight of a ceramic component consisting of one or two or more selected from talc, clay, silica, and acid clay. Painting method for long life.

The method according to claim 1, wherein the reactive calcium silicate solution in the first step uses a mixture of 5 to 20% by weight of calcium hydroxide and silicate dissolved in 80 to 95% by weight of water, and the mixture of calcium hydroxide and silicate is each A painting method for increasing the lifespan of a concrete structure, characterized in that it uses a mixture so that the ratio is 20-80:80-20 by weight.
The method according to claim 1, wherein the acrylic resin included in the water-based paint composition for blocking ultraviolet rays is at least one selected from methyl acrylate, n-butyl methacrylate, 2-ethylhexyl acrylate polymer and acrylic acid copolymer. A painting method for increasing the lifespan of a concrete structure, characterized in that using a mixture.
The method according to claim 1, wherein the fluorine-modified resin included in the water-based coating composition for blocking ultraviolet rays is composed of a mixture of a fluororesin having a weight average molecular weight of 1000 to 50,000 and an acrylic urethane resin having a weight average molecular weight of 5,000 to 100,000, and the fluororesin and The acrylic urethane resin is a coating method for increasing the lifespan of a concrete structure, characterized in that it uses a mixture in a weight ratio of 100: 100 to 150.
The method according to claim 1, wherein the UV stabilizer included in the aqueous paint composition for blocking UV rays is 10 to 20 parts by weight of SBR (Styrene-Butadiene rubber) rubber, 0.1 to 5 parts by weight of a hydroxyl acrylate monomer, 15 to 15 parts by weight of an unsaturated polyester resin Concrete characterized in that it is composed of 30 parts by weight, 0.1 to 5 parts by weight of gallic acid, 1 to 10 parts by weight of metal cations, 0.1 to 1.0 parts by weight of aluminum chloride, 0.5 to 5 parts by weight of dispersant, and 40 to 70 parts by weight of water. Painting method for long life of structures.
The method according to claim 1, wherein the siliconate-based liquid component included in the aqueous coating composition for blocking ultraviolet rays is potassium methylsiliconate 0.1 to 5 weight ratio, 3-iodo-2-propynyl-N-butyl carbamate 0.1 to 5 weight ratio , Epoxy binder resin 0.1 to 10 weight ratio and inorganic polymer containing a fluorine (F) group in a ratio of 0.1 to 5 weight ratio of the coating method for the long life of the crete structure, characterized in that it is used.
The method according to claim 1, wherein the UV absorber included in the aqueous coating composition for blocking UV is at least one selected from hydroxybenzophenone and hydroxybenzotriazole.
The method according to claim 1, wherein the water-based paint composition for blocking ultraviolet rays is added 0.1 to 5 parts by weight of one or more additives selected from the group consisting of an antifoaming agent, a dispersing agent, an antioxidant, a surface tension reducing agent, a leveling agent, an adhesion promoter, an antibacterial agent, and an inorganic pigment A painting method for increasing the lifespan of a concrete structure, comprising:
The method according to claim 1, wherein the water-based paint composition for blocking ultraviolet rays is at least one non-reactive diluent selected from the group consisting of dodecyl phenol, benzyl alcohol, propylene glycol monomethyl ether, and mixtures thereof 5 to 20 weight A painting method for increasing the lifespan of a concrete structure, characterized in that it further comprises a part.
The method according to claim 1, wherein the water-based paint composition for blocking ultraviolet rays is applied to the construction target surface using a painting, rolling, or spraying method and then cured and cured.
The method according to claim 1, wherein after the first step, the method further comprises the step of applying a waterproof mortar to the surface of the concrete structure according to the condition of the structure.
The method according to claim 11, wherein the waterproof mortar is 20-50 wt% of fast cement, 30-60 wt% of Portland cement, 5-30 wt% of alpha-type hemihydrate gypsum, and 0.1-5.0 wt% of nitrite powder After preparing a binder A painting method for increasing the lifespan of a concrete structure, characterized in that the binder is mixed with a mortar composition prepared by mixing a filler and aggregate with water and applied.
The method according to claim 1, wherein, after the second step, an acrylic urethane-based or siloxane-based water repellent is additionally coated.