KR102721735B1 - Composite Waterproofing Method for Walls Using Polyurea - Google Patents

Abstract

The present invention relates to a composite waterproofing method for a wall, wherein polyurea is applied to one of concrete and mortar surfaces, steel structures, and masonry walls, the method comprising: a pretreatment step of removing foreign substances from a construction base surface and leveling cracked areas; a subcoat forming step of applying a primer to the upper portion of the construction base surface on which the pretreatment has been completed; a first intermediate layer forming step of applying 0.5 to 1 mm of polyurea having a specific gravity of 0.07 to 1.03, a tensile strength of 20 N/mm2 or more, a tear strength of 42 N/mm2 or more, an elongation of 150% or more, and a water vapor permeability of 10 g/㎡*24hr or more on the upper portion of the subcoat layer using a roller or spray equipment; and a second intermediate layer forming step of applying 0.5 to 1 mm of the polyurea on the upper portion of the first intermediate layer. The present invention proposes a wall composite waterproofing method using polyurea, which comprises a step of forming a top coating agent including UV blocking and heat insulating properties on the upper part of the above-mentioned intermediate layer, wherein the polyurea is mixed in a weight ratio of subject matter: curing agent: filler = 1:0.7 to 0.8:0.5 to 0.6.

Description

{Composite Waterproofing Method for Walls Using Polyurea}

The present invention relates to a polyurea composite waterproofing method, and more specifically, to a composite waterproofing method for a wall using polyurea that is resistant to moisture and cracks and has improved antibacterial and durability properties.

In order to prevent corrosion or damage to structures such as concrete, steel structures, and masonry bricks due to moisture, waterproofing or anti-corrosion treatment is required on the surface of the structure. This waterproofing treatment is generally done by applying waterproofing resin to the surface of the structure.

Due to poor adhesion between the concrete and steel surfaces and the exposed waterproofing material, cracks and leaks frequently occur. As a result, the underlying concrete surface deteriorates and the steel surface corrodes. In addition, the lack of heat-insulating function due to rapid temperature changes in summer and winter causes inconvenience to the residents of the building.

In addition, the wall structure of the building may have a structure in which the wall is formed with masonry bricks, internal insulation is optionally applied to the inside, and the interior is finished with interior finish or interior materials, and external insulation is applied to the outside, or the exterior is finished with exterior finish. In the case of the masonry bricks, bricks or tiles are attached to the wall or stacked using mortar as an adhesive on the inside to finish the exterior wall. When stacking the bricks with mortar, the joints between each brick are filled with caulking material so that they can be used as an exterior wall right away. In the case of such masonry bricks, if the masonry bricks are exposed to the outside, they deteriorate or age over time, causing shrinkage in the mortar or caulking material, which causes cracks or peeling in the joint area filled with the caulking material. In addition, there is a problem in which water leakage occurs in the damaged area where the joint is cracked or peeled off. In addition, there is a problem that the appearance of the exterior wall is damaged by the efflorescence phenomenon in which the cement hardener that constitutes the mortar or the components present in the external infiltration water, such as calcium hydroxide (Ca(OH)2), sodium sulfate (Na2SO4), and calcium sulfate (K2SO4), move from the inside of the hardener to the surface in an aqueous solution state, and the precipitated efflorescence material appears after evaporation for only a few minutes. In addition, there is a problem that not only the appearance is damaged due to the efflorescence phenomenon over time, but also the appearance is further damaged by the overall color of the brick becoming blurred or the adsorption of other contaminants due to the external environment or climate.

In the case of conventional technologies, general urethane resin is used as the main material and applied only as a coating, or sheets are overlapped and constructed under the name of composite construction method, but the durability is very short, the adhesive strength and waterproof function are weak, and it is only applied to new construction. Furthermore, in the case of repair, the depth of damage to the existing surface exceeds the thickness of the coating, making repair construction impossible.

Meanwhile, polyurea is widely used as a waterproof coating material for structures because it has very high adhesion, elongation, and water resistance. In addition, it can be easily and quickly worked with a roller or spray gun, and it has the advantage of excellent workability because it hardens quickly. Therefore, polyurea is widely used as a waterproof coating material in the construction industry, and recently, research has begun to use it as a reinforcing material that improves the performance of structures in addition to its waterproof coating function.

The present invention relates to a waterproofing method for a wall using polyurea.

In addition, the present invention proposes a waterproofing method for a wall using polyurea, which can provide the function of a reinforcing material for a wall in addition to waterproofing the wall using polyurea.

In addition, another object of the present invention is to provide a composite waterproofing method for a wall using polyurea that is strong against moisture and cracks and has improved antibacterial and durability.

According to one embodiment of the present invention, in a wall composite waterproofing method for applying polyurea to any one of concrete and mortar surfaces, steel structures, and masonry walls, the method comprises: a pretreatment step of removing foreign substances from the construction base surface and leveling cracked areas;

The present invention proposes a wall composite waterproofing method using polyurea, comprising: a step of forming a lower layer by applying a primer on the upper part of a construction base surface that has completed the above pretreatment; a step of forming a first intermediate layer by applying 0.5 to 1 mm of polyurea on the upper part of the lower layer using a roller or spray equipment; a step of forming a second intermediate layer by applying 0.5 to 1 mm of the polyurea on the upper part of the first intermediate layer; and a polyurea characterized in that the polyurea is an aliphatic isocyanate prepolymer or an aliphatic isocyanate urethane/urea prepolymer resin.

According to one embodiment of the present invention, when the wall is made of high-strength concrete having a density of 260 kg/cm2 or more, blasting and grinding are performed.

In addition, the first and second intermediate layer formation steps are performed at an air temperature of 5 to 35°C, a surface temperature of 40°C or lower, and a relative humidity of 80% or lower.

In addition, the work is performed under the condition that the moisture content of the base surface of the wall is 6% or less.

Additionally, the second intermediate layer formation step is performed within 12 to 24 hours after the first intermediate layer formation step.

In addition, when the above wall is made of concrete and mortar, the above 1st and 2nd intermediate layers are formed when the pH is 7 to 9 (based on 20℃, curing for 30 days or more) and the moisture content is 6% or less.

In addition, the formation of the first and second intermediate layers is performed and cured at a temperature of 10℃ or higher, and the surface temperature is a dew point temperature of 3℃ or higher.

In addition, if the above wall is made of concrete, the first and second intermediate layers are formed when the concrete strength is at least 160 kgf/㎠.

In addition, an additive is added to the polyurea, wherein the additive is

A filler comprising at least one powder form selected from among steel fibers, carbon nanotubes, and graphite, comprising: an immersion step of immersing the filler in an antibacterial substance for 30 to 60 seconds; a drying step of drying at 80 to 100°C for 10 to 15 minutes; and a repeating step of repeating the immersion step and the drying step three times.

In addition, in the case where the wall is a masonry block, the filler includes powdered glass fiber, and the glass fiber is used in a weight ratio of 3 to 5%, and the powdered glass fiber is reinforced by mixing it with liquid polyurea at a speed of 500 rpm or higher, and the glass fiber has an average fiber length of 100 to 200 μm.

In addition, if the above wall is a steel structure, before the sublayer formation step

A polyurea wall composite waterproofing method is provided, which performs waterproofing by using any one of a sodium hydroxide (soda base)-based base treatment agent, a potassium hydroxide-based base treatment agent, a potassium carbonate (lye)-based base treatment agent, and an alkaline silicate-based base treatment agent, and diluting it with water in a ratio of 1:3 to 1:10.

In addition, the antibacterial substance includes a mixture of N,N,N-trimethylchitosan: aminoglucoside = 1.2 to 1.3: 0.8 to 1.1 in a weight ratio.

In addition, the antibacterial material comprises illite particles having an average particle diameter of 1 ㎛ to 15 ㎛, the illite particles are surface-modified with fluorine by a direct fluorination reaction, and the illite particles are present in an amount of 1 to 7 wt%.

In addition, the above intermediate layer formation step uses polyurea having a specific gravity of 0.07 to 1.03, a tensile strength of 20 N/mm2 or more, a tear strength of 42 N/mm2 or more, an elongation of 150% or more, and a water vapor permeability of 10 g/㎡*24hr or more.

According to the present invention as described above, a composite waterproofing method for a wall using polyurea can be provided.

In addition, according to the present invention, a composite waterproofing method for a wall using polyurea that is resistant to moisture and cracks, has an extended lifespan, and has improved antibacterial and durability properties can be provided.

Specific details of other embodiments are included in the detailed description and drawings.

The advantages and features of the present invention, and the methods for achieving them, will become clear with reference to the embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but can be implemented in various different forms, and unless otherwise specified in the following description, all numbers, values, and/or expressions expressing components, reaction conditions, and contents of components in the present invention are to be understood as being modified by the term "about" in all cases, since such numbers are approximations that reflect various uncertainties of measurement that occur in obtaining such values, among other things. In addition, when a numerical range is disclosed in this description, such range is continuous and includes all values from the minimum value to the maximum value inclusive, unless otherwise indicated. Furthermore, when such a range refers to an integer, all integers from the minimum value to the maximum value inclusive, unless otherwise indicated, are included.

Additionally, when a range is described for a variable in the present invention, it will be understood that the variable includes all values within the described range including the described endpoints of the range. For example, a range of "5 to 10" will be understood to include the values 5, 6, 7, 8, 9, and 10, as well as any subranges of 6 to 10, 7 to 10, 6 to 9, 7 to 9, etc., and also any value between the integers that fall within the described range, such as 5.5, 6.5, 7.5, 5.5 to 8.5, and 6.5 to 9. For example, a range of "10% to 30%" would be understood to include not only the values 10%, 11%, 12%, 13%, etc., and all integers up to and including 30%, but also any subranges such as 10% to 15%, 12% to 18%, 20% to 30%, and also any value between reasonable integers within the stated range, such as 10.5%, 15.5%, 25.5%, etc.

[First embodiment]

According to one embodiment of the present invention, a polyurea wall composite waterproofing method is proposed in which polyurea is applied to one wall such as a concrete and mortar surface, a steel structure, or a masonry wall, the wall composite waterproofing method comprising: a pretreatment step of removing foreign substances from a construction base surface and leveling cracked areas; a subcoat forming step of applying a primer to the upper portion of the construction base surface on which the pretreatment has been completed; a first intermediate layer forming step of applying 0.5 to 1 mm of polyurea to the upper portion of the subcoat layer using a roller or spray equipment; a second intermediate layer forming step of applying 0.5 to 1 mm of the polyurea to the upper portion of the first intermediate layer; wherein the polyurea is an aliphatic isocyanate prepolymer or an aliphatic isocyanate urethane/urea prepolymer resin.

In one embodiment of the present invention, the polyurea is a urethane/urea polyurea prepolymer resin, which means a transparent, one-component aliphatic transparent waterproofing material with hard elasticity used for waterproofing, and which has UV stability, non-yellowing, and resistance to alkalis and chemicals. The polyurea can be used for walls of various structures such as masonry bricks, concrete, and steel bars. The aliphatic isocyanate prepolymer is a prepolymer formed by the reaction of aliphatic isocyanate and another reactive compound (e.g., polyol). This prepolymer is used as an important intermediate for producing polyurethane compounds, and polyurethane is a high-performance polymer that can have various physical properties and is used in a wide range of applications. In the case of the aliphatic isocyanate prepolymer, since the aliphatic structure of the aliphatic isocyanate has excellent resistance to UV (ultraviolet rays), and therefore, it is preferred in applications exposed to the external environment, and has high color stability, which has the effect of reducing discoloration over time. In addition, since it is provided in the form of a prepolymer with good processability, the end user can easily manufacture the final polyurethane product by adding a curing agent, catalyst, filler, etc. according to a specific application. In addition, as a high-performance product, polyurethane based on aliphatic isocyanate has excellent mechanical properties, chemical resistance, and wear resistance, and maintains stable performance under various conditions. However, the aliphatic isocyanate prepolymer itself is highly reactive, so care must be taken when handling it, and in particular, contact with moisture must be avoided.

In addition, an aliphatic isocyanate-based urethane/urea prepolymer is used as an intermediate for producing high-performance polyurethane or urethane products, and this prepolymer is produced by the reaction of an aliphatic isocyanate with a polyol (forming a urethane) or an amine (forming a urethane). Aliphatic isocyanate is a preferred product for producing a polymer product having excellent UV resistance, little discoloration, and stable physical and chemical properties over a long period of time. The aliphatic isocyanate-based urethane/urea prepolymer resin of the present invention has excellent UV resistance. That is, the aliphatic structure provides excellent resistance to UV, so that the color and physical properties of the product are well maintained even when exposed to an external environment, and the color stability is good. That is, an aliphatic isocyanate-based prepolymer has little discoloration over time, and is suitable for use as a coating material or a transparent material. It also has excellent mechanical properties, chemical resistance, and wear resistance, so it can be used as a high-performance material in various industrial fields.

Each process will be described in more detail below.

[Preprocessing step]

The above pretreatment step may include cleaning the surface of the construction base to be constructed and removing foreign substances and moisture.

In the above pretreatment step, leveling of the cracked area may include work such as demolition of the area removed by the crack, restoration of the cross-section, application of putty, and application of mortar.

[Substrate formation stage]

In the above-mentioned sublayer formation step, the primer can be used without limitation on type, and can be applied 1 to 2 times as needed to improve adhesion to the intermediate layer.

[Middle class formation stage]

In one embodiment of the present invention, polyurea used in the intermediate layer forming step is described.

In general, polyurea is a polymer compound of the urethane series, and not only can a wide range of physical properties be controlled, but also has excellent interfacial adhesion and mechanical properties, so it is widely used as a binder-type composite material including adhesives and coating agents, and it is a material that can be applied to all types of surfaces that maintain a solid state, such as iron, wood, glass, Styrofoam, concrete, paper, and fiber.

The present invention proposes a polyurea having excellent adhesion, which can enhance adhesion performance while allowing the polyurea to spread into even the smallest gaps and adhere to the surface of a surface-treated wall. The polyurea used in one embodiment of the present invention is a urethane/urea polyurea prepolymer resin, which means a transparent, one-component aliphatic transparent waterproofing material with hard elasticity used for waterproofing, and which has UV stability, non-yellowing, and resistance to alkalis and chemicals.

In general, the types of the subject matter and the curing agent used in the production of polyurea are very diverse, and even if the subject matter and the curing agent are uniformly mixed, it may be very difficult for a uniform reaction to proceed from a microscopic perspective. The polyurea used in the present invention is a one-component aliphatic urethane/urethane resin, and uses an aliphatic isocyanate prepolymer or an aliphatic isocyanate urethane/urea prepolymer resin.

The above polyurea is non-catalytic and, when applied through spray equipment, dries within 20 to 40 seconds. It is resistant to water and temperature, is less affected by climate change, heat, cold, and moisture, and has excellent adhesive performance.

In the present invention, an additive may be added to the polyurea. The additive may include a powder form of at least one selected from among steel fibers, carbon nanotubes, and graphite.

The above additive may include a powder form, and the particle size of the powder may include 5 to 10 μm.

The present invention may include an immersion step of immersing the additive in an antibacterial substance for 30 to 60 seconds; a drying step of drying at 80 to 100°C for 10 to 15 minutes; and a repeating step of repeating the immersion step and the drying step three times.

The reason for repeating the immersion and drying steps of the above antibacterial substance is to enhance the antibacterial power by permeating the antibacterial substance into the filler.

The above antibacterial substance may include a mixture of N,N,N-trimethylchitosan:aminoglucoside = 1.2 to 1.3: 0.8 to 1.1 in a weight ratio.

The above N,N,N-trimethylchitosan may include those having a molecular weight of 2200 to 9300 and a deacetylation degree of 0.54 to 0.51, and has high antibacterial properties. The above aminoglucoside has a high level of safety with an acute toxicity LD50 of 5,000 g/kg or more, very little skin irritation or toxicity, and excellent antibacterial properties.

Meanwhile, the present invention may include illite particles having an average particle diameter of 1 μm to 15 μm. Specifically, the illite particles are surface-modified with fluorine by a direct fluorination reaction, and the illite particles may be present in an amount of 1 to 7 wt%. The illite particles are a type of clay mineral and are an environmentally friendly material. The illite particles are mainly composed of silicon (Si) and aluminum (Al), and have a thin sheet structure with a thickness of about 1 nm, and may be flexible and elastic. The illite particles are mixed with the polypropylene to form a polymer composite material, and may improve physical properties such as thermal and mechanical properties of the polypropylene, and may improve far-infrared radiation or antibacterial properties by the illite particles. If the illite particles are provided in an amount of less than 1 wt%, the effect of the illite particles is not sufficient, and if it exceeds 7 wt%, clogging may occur during the production of the foam layer (300) and the process efficiency of the foam layer (300) may be reduced. In addition, the illite particles are hydrophilic and may not be easily mixed with hydrophobic polypropylene, but the illite particles according to the present invention are surface-modified with fluorine by a direct fluorination reaction, thereby improving the mixing property with the polypropylene and making the physical properties of the foam layer (300) uniform.

The above illite particles can be mixed with the polypropylene after being surface-modified, and the surface-modified illite particles can be provided as follows. The direct fluorination reaction can be performed by placing the illite particles in a nickel boat at room temperature, mounting them in a reactor, and maintaining them in a nitrogen atmosphere for 10 to 30 minutes to stabilize them. Subsequently, the inside of the reactor can be maintained in a vacuum state, and then injecting fluorine gas at room temperature and 1 bar for 7 to 20 minutes to perform the reaction. The illite particles surface-modified by the direct fluorination reaction can be mixed with polypropylene, and then melt-mixed for 1 hour or more using an extruder to produce a pellet-shaped illite particle/polypropylene composite, which can then be molded to produce the foamed layer (300). The above illite particles may have an average particle size of 1 ㎛ to 15 ㎛. If the average particle size is less than 1 ㎛, problems such as the illite particles clumping together may occur, making it difficult to mix uniformly with polypropylene. If the average particle size is greater than 15 ㎛, it is difficult to control the thickness of the foam layer (300) to be thin. Specifically, the illite particles may have a size of 2 ㎛ to 10 ㎛, and more specifically, the illite particles may have a size of 2 ㎛ to 5 ㎛.

The above spray equipment can use a spray gun equipped with a spray nozzle.

The diameter of the above injection nozzle may include 0.3 to 0.5 mm and the injection pressure may include 5 to 20 bar.

When painting using the above spray gun, the excellent ventilation prevents external moisture and allows for the formation of a coating film without any seams even in difficult environments such as corners with complex shapes, uneven surfaces, and simple cracks. In addition, the rapid curing allows for the advantage of being able to proceed with subsequent processes immediately after spray coating work.

Meanwhile, in the present invention, if the painted surface is a masonry brick, polyurea and powdered glass fiber can be mixed and used. It is preferable to use the glass fiber at a weight ratio of 3 to 5%. In the case of masonry brick, in order to further improve the tensile strength of the reinforcing material polyurea, powdered glass fiber is mixed with liquid polyurea at a speed of 500 rpm or more to use polyurea reinforced with glass fiber. In this case, the finer the size of the glass fiber, the better it mixes with the liquid polyurea, and it is also easy to spray, so powdered glass fiber with an average fiber length of 100 to 200 μm can be used.

[Stage of formation of the upper layer]

In the above-mentioned top coating layer forming step, the top coating agent can form a top coating layer by using at least one selected from a general top coating agent and a heat-insulating top coating agent.

The top coating layer using the above top coating agent has excellent ultraviolet ray blocking and heat insulation functions, and thus the average lifespan can be improved.

The polyurea used in one embodiment of the present invention has a light transparent color and a specific gravity of 0.07 to 1.03. It also has the physical properties as shown in Table 1.

tensile strength 20 N/㎟ or more Elongation rate 150% or more Tear strength 42 N/㎜ or more Water vapor permeability 10 g/㎡*24hr or more

In the case of this concrete for the base surface in the present invention, it is preferable to use it after curing for at least 28 days at a temperature of 21℃ and a relative humidity of 50%. In addition, foreign substances such as oil, moisture, sand, dust, and laitance should be completely removed, and flatness should be maintained. In particular, in the case of high-strength concrete (260㎏/㎠ or higher), it is preferable to perform it after performing blasting/grinding treatment.

In addition, in the present invention, polyurea may require sealing in cracks, crevices, and joints in the wall. The substrate where moisture is trapped (e.g., moisture trapped under balcony tiles) needs to be dried before the intermediate layer formation step. If the surface conditions and history are not clear, it is advisable to perform an adhesion test before applying the product.

In one embodiment of the present invention, the intermediate layer forming step is performed at least 2 times and at most 4 times. In the first intermediate layer forming step, the first coating is applied to form a thickness in the range of 0.5 to 1 mm. In addition, a second intermediate layer is formed 12 hours later (at 20° C. and within a maximum of 24 hours). In the second intermediate layer forming step, the film thickness is preferably in the range of 0.5 to 1 mm. When the film thickness of the intermediate layer formation is performed at 0.5 to 1 mm, the optimal effect can be obtained. Depending on the shape or condition of the base surface, it is preferable to form the intermediate layer repeatedly 2 to 4 times. However, in the present invention, sufficient effect can be obtained with only 2 coatings.

In one embodiment of the present invention, both roller and spray can be used. In addition, solvent dilution is possible during roller or spray painting. In the present invention, the painting surface is excellent even when diluted up to 20%, but when painted at 30%, the painting surface becomes dark, so it is preferable to dilute the solvent up to 20%.

In the present invention, a more improved effect can be obtained when primer treatment is performed. In one embodiment of the present invention, a pull-off test using a dolly showed excellent adhesion (destruction of red bricks) regardless of whether tile primer treatment was performed, but in the case of no primer treatment, peel-off test (peeling resistance performance, Peel-off) showed easy peeling. Therefore, when primer treatment is performed, satisfactory results can be obtained in both pull-off and peel-off tests.

In one embodiment of the present invention, an accelerated weathering test result was performed. The accelerated weathering test is a test equipment that evaluates the weathering resistance of a material using a "QUV" ultraviolet (UV) exposure device. This equipment is mainly used to reproduce and predict damage that can occur over a long period of time in an actual environment by controlling ultraviolet light, temperature, and humidity. The QUV test is widely used to test the weathering resistance of various materials such as paints, coatings, plastics, and rubber, and can evaluate how well the material withstands discoloration, cracking, hardening, and strength reduction due to ultraviolet rays. In the embodiment of the present invention, the accelerated weathering test result shows that the gloss change rate does not differ significantly and shows excellent weathering performance.

The waterproofing process for the wall in the present invention will be described in more detail.

In one embodiment of the present invention, it is preferable to avoid working on rainy days, days with high humidity (85% or higher), days with low temperatures (5°C or lower), and days with high temperatures (ground temperature of 40°C or higher) in order to reduce cracks, poor adhesion, bubble generation, whitening, etc. of the coating film.

In addition, it is recommended to completely remove dust, grease, moisture, rust, and other foreign substances from the paint part, and to completely remove the old paint film and chalking materials on the surface of the material when performing maintenance painting. In addition, it is necessary to mix the particles evenly before painting and to stir well so that no bubbles are introduced during stirring. It is preferable to stir for at least 10 minutes. This is necessary to completely prevent the introduction of bubbles during stirring.

In addition, since the coating performance can be achieved only when the coating is applied in the prescribed order and amount during painting, it is desirable to form at least two intermediate layers, i.e., a coating film, as described above.

Meanwhile, if the painting surface is a new concrete or mortar surface, it is recommended to perform the painting when it has been sufficiently cured to a pH of 7~9 (based on 20℃, cured for more than 30 days) and a moisture content of 6% or less. If the moisture content is 6% or more, coating defects such as bubbles, poor adhesion, poor drying, and coating cracking may occur when painting.

In addition, in winter and areas with cement spurts or chalking, areas with severe absorption differences, areas with severe cement leaching, and areas with poor coating conditions (especially areas near salty seashores, areas with strong UV rays, and areas painted with low-grade paint), it is recommended to dilute a suitable substrate treatment agent at the recommended dilution ratio and pre-coat to prevent poor adhesion, discoloration, and adjust the substrate.

In one embodiment of the present invention, the pretreatment agent is used to improve the adhesion of the painted surface and to improve the quality of the paint. In the present invention, the pretreatment agent can remove dust, oil, rust, and other contaminants from the surface and properly adjust the surface so that the paint can adhere well, and this pretreatment process can greatly improve the durability, corrosion resistance, and appearance of the painted surface.

In one embodiment of the present invention, the undercoat treatment has a different purpose from the primer treatment in the above-described undercoat layer forming step. That is, the purpose of the undercoat treatment is to prepare the surface to be painted, and in this process, dust, oil, rust, contaminants, etc. on the surface can be removed to make it clean and suitable for painting. In addition, this is essential to improve the adhesion of the paint and to improve the durability and appearance of the painted surface. The undercoat treatment can be performed through chemical treatment (e.g., hydrochloric acid or phosphoric acid-based treatment agent), physical treatment (e.g., sanding, blasting), or a combination thereof.

Meanwhile, the purpose of primer treatment in the sublayer forming step of the present invention is to form a base coating layer on the surface to be painted. The primer provides an intermediate layer between the painted surface and the final paint to further strengthen the adhesion of the paint, and can play a role in preventing corrosion, correcting surface defects, and improving the durability of the painted surface. The primer is a paint with a specific chemical composition, and is applied thinly using a spray, roller, brush, etc. The type of primer varies depending on the material of the surface to be painted (metal, wood, plastic, etc.) and the final purpose of the painting work.

Therefore, the undercoat treatment can be seen as the first step in the painting process, a process of cleaning and preparing the surface, and the primer treatment is the next step in the undercoat treatment, a process of applying a base coating to the surface prepared for painting. The undercoat treatment focuses on making the surface clean and creating optimal conditions for adhesion of the paint, while the primer treatment improves the quality of the painted surface, strengthens adhesion, and plays a role in protecting the surface, which is the difference. In the present invention, the undercoat treatment can be performed in the undercoat layer formation step, i.e., before the primer treatment, and both a chemical method and a physical method can be used. In one embodiment of the present invention, a sodium hydroxide (soda base)-based undercoat treatment agent and a potassium hydroxide-based undercoat treatment agent

Use either a potassium carbonate (lye)-based primer or an alkaline silicate-based primer, diluted with water in a ratio of 1:3 to 1:10.

The above-mentioned undercoat treatment agent can be selected and used according to the material of the surface to be treated (metal, plastic, etc.), the expected environmental conditions (indoor, outdoor, high temperature, high humidity, etc.), and the final purpose of painting. Meanwhile, some undercoat treatment agents can act as a primer used before painting to further strengthen the adhesion of the paint.

In addition, in the present invention, cracks or fine parts in concrete should be cut into a V shape, filled with putty, and then polished to make them smooth.

In the present invention, the ambient temperature at the time of painting or curing is suitably 10℃ or higher, and the surface temperature is preferably the dew point temperature of 3℃ or higher to avoid moisture condensation. Meanwhile, when the concrete strength of the wall is 260 kgf/㎠ or higher, it is difficult to treat the surface by grinding, which may cause poor adhesion, so it is preferable to form a roughness by treating the surface by blasting/grinding. In the present invention, the concrete strength of the wall must be at least 160 kgf/㎠ or higher when painting. In the present invention, it is preferable to paint the connecting parts of the wall by overlapping them by about 15 cm.

[Second embodiment]

Meanwhile, in another embodiment of the present invention, the intermediate layer forming step may include a mixture of polyurea: subject: curing agent: filler = 1:0.7 to 0.8:0.5 to 0.6 in a weight ratio.

The above filler may include at least one powder type selected from among steel fibers, glass fibers, carbon nanotubes, and graphite.

The above filler may include a powder form, and the particle size of the powder may include 5 to 10 μm.

The above filler may include an immersion step of immersing the filler in an antibacterial substance for 30 to 60 seconds; a drying step of drying at 80 to 100°C for 10 to 15 minutes; and a repeating step of repeating the immersion step and the drying step three times.

The reason for repeating the immersion and drying steps of the above antibacterial substance is to enhance the antibacterial power by permeating the antibacterial substance into the filler.

The above antibacterial substance may include a mixture of N,N,N-trimethylchitosan:aminoglucoside = 1.2 to 1.3: 0.8 to 1.1 in a weight ratio.

The above N,N,N-trimethylchitosan may have a molecular weight of 2200 to 9300 and a deacetylation degree of 0.54 to 0.51, and has high antibacterial properties.

The above aminoglucoside is highly safe with an acute toxicity LD50 of over 5,000 g/kg, has very little skin irritation or toxicity, and has excellent antibacterial properties.

The above subject matter may include at least one selected from Hexamethylene diisocyanate, Isophorone diisocyanate, Methylene biscyclohexyl diisocyanate, Toluene diisocyanate, Naphthalene diisocyanate, Methylene diphenyl diisocyanate, and Bitoluene diisocyanate.

The above curing agent may include at least one selected from butanediol, ethylene diamine, methylene bis chloroaniline, ethylene glycol, and hexanediol.

The above spray equipment can use a spray gun equipped with a spray nozzle.

The diameter of the above injection nozzle may include 0.3 to 0.5 mm and the injection pressure may include 5 to 20 bar.

When painting using the above spray gun, the excellent ventilation prevents external moisture and allows for the formation of a coating film without any seams even in difficult environments such as corners with complex shapes, uneven surfaces, and simple cracks. In addition, the rapid curing allows for the advantage of being able to proceed with subsequent processes immediately after spray coating work.

In the above-mentioned top coating layer forming step, the top coating agent can form a top coating layer by using at least one selected from a general top coating agent and a heat-insulating top coating agent.

The top coating layer using the above top coating agent has excellent ultraviolet ray blocking and heat insulation functions, and thus the average lifespan can be improved.

In this way, the polyurea composite waterproofing method of the present invention includes a filler containing an antibacterial substance in the intermediate layer forming step, so that it has excellent adhesion performance and is resistant to moisture and cracks, thereby extending the average lifespan and providing a polyurea composite waterproofing method with improved antibacterial properties and durability.

In this way, the composite waterproofing method of a wall using polyurea of the present invention includes a filler containing an antibacterial substance in the intermediate layer forming step, so that it has excellent adhesion performance and is strong against moisture and cracks, thereby extending the average lifespan, and can provide a composite waterproofing method of a wall using polyurea with improved antibacterial properties and durability.

Those skilled in the art will appreciate that the present invention can be implemented in other specific forms without changing its technical idea or essential characteristics. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. The scope of the present invention is indicated by the scope of the claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

Claims (11)

In a composite waterproofing method for walls, polyurea is applied to concrete and mortar surfaces, steel structures, and masonry walls.
Pretreatment step to remove foreign substances from the construction surface and level cracked areas;
A step for forming a lower layer by applying a primer on the upper part of the construction base surface that has completed the above pretreatment;
A first intermediate layer forming step of applying 0.5 to 1 mm of polyurea on top of the above-mentioned lower layer using a roller or spray equipment; and
A second intermediate layer forming step of applying 0.5 to 1 mm of the polyurea on top of the first intermediate layer; including,
The above first and second intermediate layer formation steps are performed at an air temperature of 5 to 35°C, a surface temperature of 40°C or lower, and a relative humidity of 80% or lower.
The above 1st and 2nd intermediate layer formation is performed and cured at a temperature of 10℃ or higher and the surface temperature is a dew point temperature of 3℃ or higher.
The above polyurea is an aliphatic isocyanate prepolymer or an aliphatic isocyanate urethane/urea prepolymer resin, and an additive is added to the polyurea, wherein the additive includes at least one powder form selected from among steel fibers, carbon nanotubes, and graphite, and comprises an immersion step of immersing the additive in an antibacterial substance for 30 to 60 seconds; a drying step of drying at 80 to 100°C for 10 to 15 minutes; and a repeating step of repeating the immersion step and the drying step three times.
The above antibacterial substance is,
A wall composite waterproofing method comprising a mixture of N,N,N-trimethylchitosan:aminoglucoside = 1.2 to 1.3: 0.8 to 1.1 in a weight ratio, illite particles having an average particle diameter of 1 ㎛ to 15 ㎛, the illite particles being surface-modified with fluorine by a direct fluorination reaction, and polyurea containing 1 to 7 wt% of the illite particles. In the first paragraph,
A polyurea wall composite waterproofing method that performs blasting and grinding when the above wall is made of high-strength concrete of 260 kg/cm2 or more. In the first paragraph,
The above first and second intermediate layer formation stages are performed at an air temperature of 5 to 35°C, a surface temperature of 40°C or lower, and a relative humidity of 80% or lower. This is a polyurea wall composite waterproofing method. In the third paragraph,
A polyurea composite waterproofing method for walls, which is performed under the condition that the moisture content of the base surface of the wall is 6% or less. In the first paragraph,
A wall composite waterproofing method using polyurea that forms the first and second intermediate layers when the above wall is a concrete and mortar surface, and has a pH of 7 to 9 (based on 20℃, curing for 30 days or more) and a moisture content of 6% or less. In the first paragraph,
A wall composite waterproofing method using polyurea to form the first and second intermediate layers when the above wall is made of concrete and the concrete strength is at least 160 kgf/㎠. delete In the first paragraph,
In the case where the above wall is a masonry block, the additive includes powdered glass fiber,
A wall composite waterproofing method in which glass fiber is used in a weight ratio of 3 to 5%, the powdered glass fiber is mixed with liquid polyurea at a speed of 500 rpm or more for reinforcement, and the glass fiber has an average fiber length of 100 to 200 μm. In the first paragraph,
If the above wall is a steel structure, before the sub-layer formation step
A polyurea wall composite waterproofing method that uses any one of sodium hydroxide (soda base)-based primer, potassium hydroxide-based primer, potassium carbonate (lye)-based primer, and alkaline silicate-based primer, and dilutes it with water in a ratio of 1:3 to 1:10 to perform undercoat removal. delete In the first paragraph,
The above intermediate layer formation step is a wall composite waterproofing method using polyurea with a specific gravity of 0.07 to 1.03, a tensile strength of 20 N/mm2 or more, a tear strength of 42 N/mm2 or more, an elongation of 150% or more, and a water vapor permeability of 10 g/㎡*24hr or more.