KR100956841B1 - Paint coating and new paint coating method after removing old paint - Google Patents

Abstract

PURPOSE: A method for painting an old film and a painting film using the same are provided to prevent minute dust from being coated on the old film using rotating discharge nozzle high pressure washing task. CONSTITUTION: A method for painting an old film comprises the following steps: a base preparation step(S101); a base adjustment step including a base adjustment work step(S102) and a base completion step(S103); a primer coating step(S200) including a primer preparation step(S201), a primer work step(S202), and a primer dry step(S203); a finish coating step(S300) including a finish coating preparation step(S301), a finish coating work step(S302), a finish coating dry step(S303), and a finish completion step(S304).

Description

Paint coating and new paint coating method after removing old paint}

The present invention relates to a recoating method of an old coating film and a coating film using the same, and more particularly, a background adjustment step using high pressure washing, a bottom coating step using a modified epoxy resin, and a top coating step using a urethane resin or a modified epoxy resin. The present invention relates to a recoating method of an old coating film having a high lifespan effect of steel structures and a high work efficiency of recoating, and a recoating coating film using the same by recoating the old coating film.

The old film recoating method according to the prior art is composed of a background adjustment step, a coat coating step and a top coat coating step.

In the background adjustment step, scrapers, wire brushes, sandpaper, hammers, and power tools such as electric sanders, electric brushes, Background adjustment work has been carried out using jet boats.

The old film defect part of the above-described background adjustment step is an impurity such as rust, oil, moisture, and dust, and the old film damaged part is a damaged layer and a weak film layer due to external impact and external climate.

In the background adjustment work, contaminants that are invisible to the naked eye, such as fine dust and powdered old coating film, were left on the old coating film and were repainted so that there was a problem of deteriorating the quality of the coating film such as poor adhesion of the paint and peeling phenomenon.

As described above, since the work is performed by applying friction or impact to the surface to be coated by manual work, there is a problem in that the labor cost is increased and the work efficiency is lowered. In addition, due to such problems, there was a problem in that the cost was adjusted by setting the background adjustment area to about 20% to 60% of the total area of the repainting.

As for the coating process, KS standard, anti-corrosive paint, 1 kind light blue combination paint, 1 kind light bright combination paint, 1 kind light bright combination paint, 1 kind light bright combination paint, 2 kind zinc rust paint 1 2, 2 types of zinc chromate paints, 3 types of zinc powder primers, 3 types of zinc powder primers, 3 types of zinc powder primers, 1 type of 4 etching primers, 2 types of 4 etching primers It is defined as the Jong Kwang Myung Dan Chromium Federal Agency Primer and 6 kinds of tar epoxy resin paints.

KS standard products were mainly used for the existing designed and constructed facilities, and Kwang Myung Dan (rust paint) paint was generally applied among the rust-preventive paints of KS standard products listed above.

Gwangmyeongdang, a rust paint, is composed mainly of lead-based pigments and rheological resins. The antirust effect of light list can be divided into corrosion protection method, passivation method and corrosion prevention method using lead.

Corrosion environment blocking method serves to prevent contact with oxygen, water and other corrosive substances by coating on the surface of the coating.

The passivation method increases the anode polarization or the cathode polarization of iron to suppress the reaction between the cathode and the anode.

The corrosion prevention method using lead lowers the corrosion current value and prevents iron from ionizing and reacting with oxygen.

This corrosion prevention method using lead uses a basic pigment to prevent oxidation by making the alkaline atmosphere of iron and serves to prevent corrosion by using lead, which has a tendency to ionize than iron.

However, linseed oil and alkali-based resins used as rheological resins differ greatly in terms of their functions from urethane-based and epoxy-based resins. Especially, iron-based facilities that are exposed to bridges, ship structures, and chemicals that are close to sea level High-performance anti-corrosive paints are required where exposed to plant equipment, chemical equipment and harsh environments.

As described above, excellent anti-rusting and chemical composition is applied to the surface of facilities such as environmental office facilities, waste treatment facilities, railway bridges and bridges that require durability by vibration, shock, and friction. Excellent paint resistance (alkali resistance, acid resistance, chemical resistance), low porosity, strong adhesion, impact resistance, abrasion resistance, friction resistance, weather resistance, moisture resistance, water resistance paint coating is required.

Nevertheless, the coated rosters (rust paints) have been implemented without consideration of the protective measures of the facility by coating them only for corrosion protection and adhesion to tops. Therefore, when the repainting cycle arrives, there is a problem in that the light coating (rust paint) of the same material is used due to the adhesion with the existing paint.

Since the light list (rust paint) is hard to reach the coating thickness (100 μm or more) to be obtained by one coating (30 μm to 40 μm), the coating is usually repeated two or three times to obtain a coating film of a desired thickness. .

In the above repainting, it is common to repaint after a few days on the coating film formed by a single coating depending on the working conditions. Therefore, the light list (rust paint) has a high cost economic process of the process by repeating two or three times as well as the adhesion between the existing coating and the newly painted coating due to the adhesion of impurities during the drying process.

When repainting on the light film (rust paint), which is a high-performance paint, urethane resin or epoxy resin, it is difficult to adhere due to strong solvents, resulting in poor adhesion and bubbles on the coated surface. There was a problem that the construction itself can not do because of the old film.

Along with the above-mentioned problems, there is a problem in that the curing reaction of the urethane-based resin or the epoxy-based resin to be repainted may not be performed even if it is cured.

Top coat is KS standard and oil paint is 1 class paint, 1 class paint, 2 class natural drying enamel 1 class, 2 natural drying enamel 2 class, 2 natural drying It is defined as enamel semigloss, two kinds of natural drying type enamel matte, three kinds of aluminum paint, four kinds of acrylic paints.

KS standard products were mainly used for the existing designed and constructed facilities, and combination paints and enamel paints were generally applied among oil paints of KS standard products listed above.

Combination paints and enamel paints, which are the same resin system as the resin system of the light film (rust paint), have been used as the top coat where the composition film is the light paint (rust paint).

The above-mentioned combination paint and enamel paint is an internal and external finishing paint of steel building, steel, machinery, wood, etc., and has a strong coating, various colors, gloss retention, workability and efficiency.

In addition, due to its low price, it is widely used as an economic top coat. However, the linseed oil and the alkali-based resin, which are the resins of the combined paint and enamel paint, as described above in the coating process, are paints with high functionality.

This prevents facility protection measures due to these finishes, and the repainting cycle is accelerated due to the top coat due to the aesthetic effect only by adhesion and color and gloss with the topcoat, and the aging of the facility is also accelerated.

In case of repainting with the above-mentioned high-performance urethane-based and epoxy-based paints, the coating film damages such as poor adhesion due to the peeling of the old film, bubbles in the coated surface, and swelling due to the strong solvent of the high-performance paint. There was a problem that can not do the construction itself.

As described above, there is a problem in that the strong solvent may affect the curing reaction of the urethane-based resin or the epoxy-based resin to be repainted, and thus, even if the resin is cured, it may not function properly.

Accordingly, the present invention was created to solve the above problems, the object of the present invention is as follows.

First, the purpose is to solve the problem that the construction work on the old film as it is not visible to the naked eye such as fine dust, contaminants, powdered old film, as well as high workability in the background adjustment step when repainting the old film.

Second, the purpose is to reduce the work time and labor costs when repainting the old film.

Third, the purpose is to easily obtain the dry film thickness desired by the operator when repainting the old film.

Fourth, the purpose is to prevent the low-function damage when repainting the old film.

Fifth, the purpose is to increase the efficiency of repainting, such as durability and extension of the repainting cycle.

As described above, technical means for achieving the object of the present invention is as follows.

The background adjustment step is a background preparation step for preparing a high pressure cleaner with a pressurized nozzle, a background adjustment operation step for removing defects and damage parts of the old film from the surface to be coated using the prepared high pressure cleaner, and removal of defect parts and damage parts of the old film. Completion step of drying and cleaning the coated surface; The undercoat coating step includes the undercoat preparation step of preparing the undercoat material of the undercoat, the undercoat work step of painting the coated surface using the prepared undercoat material, and the undercoat drying step of drying the finished undercoat surface; And the top coat painting step, a top coat preparation step of preparing top coat material of top coat coating, a top coat operation step of painting work on the bottom coat surface using the prepared top coat material, a top coat drying step of drying the finished top coat surface and a finished top coat surface Cleaning and finishing the top coat completion step; repainting method comprising a.

In the background adjustment step, the pressure nozzle of the high pressure cleaner rotates; The injection pressure of the pressurizing nozzle in the background adjustment step is 140 to 160 BAR; Rotational speed of the pressurizing nozzle in the background adjustment step is characterized in that 100 ~ 1000rpm.

The order of removing the old film of the surface to be coated in the background adjustment step is removed from the edge to the wide side, left, right, and top to bottom; Drying time in the background adjustment step is characterized in that 4 to 19 hours depending on the outside temperature.

In the coating process, the coating material is a modified epoxy resin; The coating thickness of the undercoating surface in the undercoating step is 90 ~ 110㎛; In the undercoat coating step, the drying time of the undercoat is characterized in that 16 to 96 hours.

The topcoat material in the top coat step is urethane resin or modified epoxy resin; When the urethane resin is used in the top coating step, the coating thickness of the top coating surface is less than 30 ~ 40㎛; When the urethane resin is used in the top coat step, the drying time of the undercoat is characterized in that 6 ~ 72 hours.

When the urethane resin is used in the top coat step, the urethane resin is repeatedly coated on the top coat surface, and the total thickness of the top coat surface is 60 to 80 μm, and the total drying time is 12 to 84 hours.

When the modified epoxy resin is used in the top coat step, the coating thickness of the top coat surface is 90 to 110 μm; When the modified epoxy resin is used in the top coat phase, the drying time of the sewer surface is 16 to 96 hours depending on the outside temperature.

It is characterized by a repainted coating film constructed by the repainting method described above.

As mentioned above, the effect of this invention is as follows.

First, there is an effect of eliminating the problem of being installed on the old film as it is not visible to the naked eye such as fine dust, contaminants, powdered old film as well as high workability during the background adjustment step using the rotating pressure nozzle high pressure washing operation.

Second, by applying pressure nozzle high pressure washing that rotates the entire background adjustment step that could not be done by manual operation due to high cost and low efficiency, it is effective to work on low cost and high efficiency background adjustment step by reducing work time and labor cost. have.

Third, by using the modified epoxy resin in the undercoat coating step, it is possible to easily obtain the thickness of the high-performance paint and dry coating desired by the operator.

Fourth, by coating with a urethane resin or a modified epoxy, which is a high-performance topcoat according to the environment and conditions in the top coat step, there is an effect of preventing the low-functional damage during repainting.

Fifth, by using a high-performance top coat having a function appropriate to the environment and conditions, it has the effect of improving the efficiency of repainting work, such as durability and repainting cycle extension.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

<Method according to the present invention>

1 is a flowchart illustrating a recoating method of an old film according to the present invention. As shown in FIG. 1, the recoating method of the composition film according to the present invention includes a background adjustment step (S100), a bottom coating step (S200), and a top coating step (S300).

Background adjustment step (S100) consists of a background preparation step (S101), a background adjustment operation step (S102) and a background completion step (S103). At this time, the background adjustment step (S100), as shown in Table 1 below, the work through the high-pressure washing operation in the background adjustment step (S100) can see a work effect almost similar to sandblasting.

High pressure cleaning work has no disadvantages such as installation of sand booth, scattering, dust, wide range of use, and is more effective than manual adjustment work by hand.

Background preparation step (S101) is to prepare a high-pressure washing machine having a pressurized nozzle, the defects such as swelling, peeling, cracking, oil, vulnerable layer of the rust-generating coating film of the base surface for repainting completely removed to prevent painting It is to prevent this from happening. At this time, the pressure nozzle rotates.

As described above, the quality of the painted surface is increased, and as shown in Table 2 below, the contribution rate of the surface adjustment to the coating life is large, contributing to the coating quality compared to other processes.

As described above, since the background preparation step (S101) requires careful attention to the background adjustment of the surface to be coated, the background preparation step (S101) is prepared by the high pressure washing method of rotating the pressurized nozzle with high efficiency and low cost.

 Background adjustment work step (S102) is to remove the defects and damaged parts of the old film on the surface of the coating using the prepared high pressure cleaner, the high pressure washer is composed of a high pressure washer and a water supply facility, a rotating pressure nozzle, a high pressure hose, the nozzle Spray nozzles and rotating nozzles shall be prepared.

As described above, the old film defect part is an impurity such as rust, oil, moisture, and dust, and the old film damaged part is a damaged layer and a weak layer of the coating layer due to external impact and external climate.

As described above, the background adjustment operation step (S102) is not to remove all of the old coating film, but to remove defects and damaged portions of the old coating film and repaint the high-performance paint thereon.

As described above, when the repaint is completely removed after the old film is removed, it may be more expensive than the cost of replacing the new product due to the problem of high cost during the background adjustment work.

As a result, the surface to be coated is damaged in order to completely remove the portion that is completely attached to the surface to be coated and forms a complete coating surface. Therefore, sufficient background adjustment effect can be obtained only by removing the defect part and damage part of an old film.

As described above, sufficient background adjustment effect can be obtained only by removing the defective part and damaged part of the old film, so that the defective part and damaged part of the old film are removed by the background adjustment work, and the remaining coated surface is removed from the coated surface. Prevention of damage to the old film, such as poor adhesion due to old film peeling phenomenon, bubble generation and seizure due to the strong solvent on the old film which is completely attached to form a high coating force and complete coating surface; For sake. It is also to coat the top coat of high functional paints.

As described above, the present invention is suitable for maintenance coatings by using a high-performance paint repainting, so that the coating film is soft and permeable and excellent in adhesion even on an unstable ground or a somewhat rusted steel surface which has not been possible until now. , Alkyd, acrylic resin) and excellent adhesion.

In addition, repainting high-performance paint can be obtained excellent anti-rusting power by one coating. At this time, it is possible to paint on almost all metal surfaces, and it is used as a coating material for modified epoxy resin, which is a high-performance paint with a strong coating film, excellent impact resistance and abrasion resistance.

The spray nozzle is a nozzle that is basically provided to a general high pressure cleaner, and sprays water in a fan, cone, and straight line. It is used for cleaning during high pressure washing.

The rotating pressurized nozzle is discharged while the water rotates by a shaft inside the nozzle, unlike a general spray nozzle. At this time, even if the same pressure is ejected, when the water is rotated and discharged, the frictional force with the surface is increased, thereby increasing the cleaning effect by 20% to 30%.

In the background adjustment step (S100), the rotary nozzle mainly removes impurities such as rust, oil, moisture, and dust, and deposits that may interfere with the painting work, and weak coating layers.

Background adjustment by high pressure washing operation using rotating pressurized nozzle is installed by installing high pressure washer with pressure of 140 BAR or more, and using rotating pressurized nozzle, the most suitable pressure is 150 BAR and it is suitable for rust, oil, moisture, dust, etc. Remove impurities and coating weak layer which may interfere with painting work.

Such high pressure cleaning can be carried out on the entire surface to be coated.

The high pressure unit 1BAR of the high pressure washing operation using the rotating pressure nozzle is almost the same as 1kgf / ㎠, so the force of 150BAR or more of the high pressure washing operation using the rotating pressure nozzle is 150cm or more in 1cm2 to remove impurities. As a result, higher efficiency can be obtained than manual adjustment by hand.

The spraying method for high pressure cleaning using the rotating pressure nozzle uses the rotating pressure nozzle to start the work from the upper part to the lower part, starting at the corner where the face meets and moving to the wide face. . That is, it sprays onto the surface to be coated while moving from left to right and right to left.

 Background completion step (S103) is to dry and clean the coated surface from which the defects and damaged parts of the old film are removed, and 4 hours (outside air temperature 30 ° C.) to 19 hours so that the surface of the coated surface can be painted. (Ambient air temperature 5 ℃) to achieve the undercoat coating step (S200).

Where the drying is insufficient, or expected place during the above-described background completion step (S103) is forced to dry using a hot air blower or blower so as not to interfere with the work in the coating step (S200).

At the same time, remove water and foreign substances from the bottom after high pressure cleaning.

The undercoat coating step (S200) is composed of the undercoat preparation step (S201), the undercoat operation step (S202) and the undercoat drying step (S203).

Undercoat preparation step (S201) is to prepare the undercoat material to coat the undercoat on the finished work in the background adjustment step (S100), the undercoat material of the undercoat coating step (S200) uses a modified epoxy resin. At this time, it is preferable to use the modified epoxy resin, which is a paint used for the undercoat material, of Edmatic HB Silver of KCCO.

The use of the above-mentioned Edmatic HB Silver removes defects and damages of the old film by the background adjustment work, and when the strong solvent is used on the old film which is attached to the remaining coated surface and has a high bonding strength and a complete coating surface, the old film is peeled off. This is to prevent damage to the old film, such as poor adhesion due to the phenomenon, bubbles generated on the surface to be coated, and jamming. It is also to coat the top coat of high functional paints.

Edmatic HB silver used in the present invention is excellent in adhesiveness even on the unstable base or somewhat rusted steel surface, which has never been possible because of excellent softness and permeability of the coating film, and is suitable for repair coating and various coating films (epoxy, rubber chloride, alkyd, acrylic resin) Excellent adhesiveness and excellent anti-corrosion power can be obtained by one coating.

As a result, Edmatic HB Silver can be coated on almost all metal surfaces, and the modified epoxy resin, Edmatic HB Silver, which has a strong coating film, excellent impact resistance and abrasion resistance, is used as a coating material.

The modified epoxy resin is a modified polyepoxy resin using aluminum in the modified epoxy resin to modify the defects exhibiting the inherent performance of the epoxy and poor color and weather resistance when exposed outdoors.

At the same time, the modified epoxy resin has a coating thickness of 100 μm, which is excellent in anti-rusting and chemical resistance (alkali resistance, acid resistance, chemical resistance), low porosity, strong adhesion, impact resistance, abrasion resistance, and friction resistance. It forms a soft coating of weather resistance, moisture resistance and water resistance.

The above-mentioned coating film is soft and permeable, so it is excellent in adhesion to unstable ground or somewhat rusted steel surface, which is impossible until now, and is suitable for maintenance coating, and can be painted on various old coating films (epoxy, chloride chloride, alkyd and acrylic resin). Only high antirust and durability can be expected.

As shown in Table 3, the characteristics of the above-described manufacturer Construction Chemicals Co., Ltd. Edmatic HB Silver is as follows.

EdMastic HB Silver is a polyamine cured two-part coating material made of thick film-type modified epoxy resin and aluminum, and has an anti-rust effect. At this time, the Edmatic HB silver is made of a mixture of Edmatic HB silver main material, Edmatic HB silver hardener, diluent in a weight ratio of 4: 6: 1. In other words, if the Edmatic HB silver main body is 40 parts by weight, 80 ml of Edmatic HB silver hardener and 10 g of diluent are used.

Edmas HB silver is suitable for repair coating because it has excellent adhesion even on a somewhat rusted steel surface. It has excellent adhesion with various composition films (epoxy, rubber chloride, alkyd, acrylic resin) and excellent anti-corrosion power with one-time coating. You can get it. At this time, almost all metal surfaces can be painted, and the coating is firm, and it has excellent impact resistance and abrasion resistance.

Undercoat work step (S202) is to paint the surface to be coated using the prepared undercoat material, if the base adjustment step (S100) using high-pressure washing in the undercoat coating step (S200) is made, the undercoat coating after drying is sunny Start with a well-ventilated place that dries quickly.

Undercoat operation step (S202) is coated with a mixture of modified epoxy resin to a thickness of 100㎛ once using a brush, roller, spray on the repainting surface on which the background adjustment is made. At this time, modified epoxy resin takes about 5.7 ~ 8.5㎡ / ℓ.

When using the brush and the roller during the work in the undercoat operation step (S202), it is preferable to paint the corners or corners with a brush first, and then paint a wide area with the roller.

The modified epoxy resin during the work in the work under construction (S202) is mixed with the main component and the hardener with a two-part paint, and after the pot life (12 hours), the gel phenomenon (firmness) is generated and used within the pot life. Therefore, only the necessary amount is mixed and used in the preparation step (S201).

The undercoat drying step (S203) is to dry the finished undercoat surface, and the drying time is 5 hours for dry contact and 24 hours for curing when the outside temperature is 20 ° C.

The undercoat drying step (S203) is completely dried after 16 hours (outside air temperature 30 ° C.) to 96 hours (outside air temperature 5 ° C.) to form the undercoat layer. The repainting interval is 24 hours when the outside temperature is 20 ℃. Therefore, the undercoat drying step (S203) it can be seen that the drying time varies depending on the outside temperature.

Top coat painting step (S300) consists of a top coat preparation step (S301), top coat operation step (S302), top coat drying step (S303) and top coat completion step (S304). At this time, the top coat step (S300) is the same as the top coat step (S300) depending on which of the top coating material, that is, urethane resin or modified epoxy resin used for top coat, but the detailed work process is different.

Hereinafter, the description of the upper coat painting step (S300) will be described separately in the first embodiment using a urethane resin and the second embodiment using a modified epoxy resin.

<First embodiment of the top coat step (S300)>

The top coat painting step using the urethane resin (S300) is an environmental facility facility, a waste treatment facility, which is a steel facility that may be corroded by pollutants, railroad bridges, bridges, plant equipment, etc., which require durability by vibration, impact, and friction. Excellent adhesion to steel structures such as cranes, environmental facilities, steel towers, and sculptures, which are industrial facilities, and excellent durability, chemical resistance, weather resistance, and urethane resins, which are highly functional paints with high gloss and gloss retention rates. It can increase the efficiency of repainting work such as extension.

Top coat preparation step (S301) is to prepare a top coat material of the top coat, urethane resin is preferably used acrylic urethane, which is a paint of the manufacturer Construction Chemical Industry Co., Ltd. In this case, the reason is that acrylic urethane, which is a paint of the same construction company, is being used in consideration of the binding property and reactivity of the paint on the undercoat.

The characteristics of the urethane resin described above are as follows.

There are several types of paints among those called urethane resin paints. Specifically, there are various things such as a urethane bond introduced into the resin in advance, an isocyanate group at the resin terminal, and a polyisocyanate or blocked isocyanate as a curing agent.

As described above, no matter what paint is used, after the film is formed, the coating film has a urethane bond. A hydrogen bond acts between these urethane bonds, which gives the resin a strong bond as a secondary bonding force.

In general, the coating film having a urethane bond is easy to achieve both hardness and flexibility to form an excellent coating film of impact resistance, abrasion resistance, chemical resistance and weather resistance.

The characteristic of the above-mentioned acrylurethane is as follows.

Acrylurethane is an egg-yellowing urethane resin paint mainly composed of acrylic resin and isocyanate. It has excellent adhesion to materials, excellent chemical resistance and weather resistance, and excellent gloss and gloss retention.

Acrylurethane is composed of acrylurethane main material, acrylurethane curing agent, and diluent. The mixing ratio of urethane resin and curing agent is mixed in the ratio of 4: 1 by weight, and the mixing ratio of diluent is mixed from 5% to 10%. That is, after mixing 40 g weight part of acryl urethane main material and 10 g weight part of acryl urethane hardeners, 2.5-5 weight part diluent is mixed.

The top coat operation step (S302) is to paint the undercoat surface using the prepared topcoat material. In the top coat phase using the urethane resin (S300), the urethane resin mixture is poured onto the dried undercoat layer using a brush, roller, and spray. To paint.

Top coat work step (S302) is painted with a thickness of 30㎛ ~ 40㎛ at a time and after the 6 hours (outside air temperature 30 ℃) ~ 12 hours (outside air temperature 5 ℃) 1 time by additional coating 60㎛ ~ 80㎛ Complete drying to a thickness forms a top coat layer. At this time urethane resin takes about 11 ~ 13㎡ / ℓ once paint.

Top coat work step (S302), when using a brush and roller paint the corners or corners with a brush first and a large area should be painted with a roller. Also, urethane resin should be used within pot life because it is impossible to use due to gel development (hardness) after pot life (8 hours) by mixing main component and hardener with two-part paint. Therefore, only the necessary amount in the top preparation step (S301) should be mixed.

The top coat drying step (S303) is to dry the finished top coat surface, and the drying time is 30 minutes for dry touch and 8 hours for curing when the outside temperature is 20 ° C. At this time, after 6 hours (outside temperature 30 ℃) ~ 72 hours (outside temperature 5 ℃) according to the temperature of the outside air is completely dried to form a top coat layer.

The top coat finish step (S304) is to clean and finish the dried top coat surface. After confirming that the top coat layer is completely dried, check whether there are insufficient parts or defects that may cause the defect, and then perform corrective work. .

After all the above-mentioned modifications are completed, materials and tools are cleaned up and withdrawn. At this time, remove the foreign substances and wastes generated after work.

<Second embodiment of the top coat step (S300)>

The top coat painting step using modified epoxy resin (S300) is exposed to the harsh environment such as steel facilities, bridges, ship structures, and steel facilities that are exposed to chemical components, and is exposed to poor environments, and corrosion by water and gas is concerned. We use for facility to become.

As described above, deterioration of chemical components (alkali resistance, acid resistance, chemical resistance), low porosity, strong adhesion, impact resistance, abrasion resistance, friction resistance, weather resistance, moisture resistance, and water resistance By painting epoxy resin, the efficiency of repainting can be improved, such as durability of the material and extension of repainting cycle.

Top coat preparation step (S301) is to prepare a top coat material of the top coat, it is preferable to use a modified epoxy resin, a top coat material of Edmastic HB of KEPCO. At this time, the reason is that Edmas HB, which is a coating material of the same construction company in consideration of the binding property and reactivity of the paint coating surface.

Edmatic HB is a polyamine cured two-component topcoat finish using thick film-type modified epoxy resin and various colors of rust preventive pigments.

In addition, the description of the Edmatic HB is the same as the detailed description of the modified epoxy resin as described above, and the detailed description thereof will be omitted.

The top coat operation step (S302) is to paint the surface of the undercoat using the prepared topcoat material. In the top coat operation step (S302) using the modified epoxy resin, the modified epoxy resin mixture is poured onto the dried undercoat layer, roller, spray The coating is carried out in a thickness of 100 μm once using.

The coated top coat is completely dried after 16 hours (outside air temperature 30 ℃) to 96 hours (outside air temperature 5 ℃) according to the temperature of the outside air to form a top coat layer. At this time, modified epoxy resin takes about 5.7 ~ 8.5㎡ / ℓ.

When using the brush and the roller in the top work step (S302), it is preferable to paint the corner or corner portion first with a brush, and then paint a wide area with the roller.

The modified epoxy resin is a two-component paint mixed with a main agent and a curing agent, and when the pot life (12 hours) elapses, gel development occurs (hardness), so it is not possible to use the pot life. Therefore, it is preferable to mix and use only the necessary amount in the top preparation step (S301).

The top coat drying step (S303) is to dry the finished top coat surface, and the drying time is 5 hours for dry contact and 24 hours for curing when the outside temperature is 20 ° C. At this time, it is preferable to dry completely after 16 hours (outer air temperature 30 degreeC)-96 hours (outer air temperature 5 degreeC) according to the temperature of outside air.

The top coat completion step (S304) is to clean and finish the dried top coat surface, and after confirming that the modified epoxy resin, which is a completely dried top coat, is completely formed on the painted surface, examines whether there is a part that may be insufficient or causes a defect. Afterwards, corrective action is performed. At this time, after all corrective work is finished, materials and tools should be arranged and withdrawn.

When the above-mentioned correction is finished, the surrounding foreign matter and the waste generated after the operation are removed.

In particular, the present invention, as shown in Table 4 below, when the background adjustment operation, cleanliness 1 type (1 keren) high workability, as well as fine dust, contaminants, powdered old film is not visible to the naked eye, such construction on the old film Solve the problem.

At the same time, it is possible to apply the entire base adjustment work, which could not be done by manual operation due to the high cost and low efficiency, to apply the high pressure washing operation to the rotating pressure nozzle, and to reduce the working time and labor cost. can do.

Looking at the performance of various paints as shown in Table 5 below it can be seen that the performance of the coating film of the urethane resin series and epoxy resin series. Therefore, in the present invention, the urethane resin series and the epoxy resin series can be used as the undercoat and top coat materials.

<In accordance with the present invention Repainted Of paint  Structure

The repainted coating film 1 using the above-described old coating film repainting method is formed with a lower coating film 3 on the base surface 2 and an upper coating film 4 on the upper surface thereof.

<In accordance with the present invention Repainted Of paint  My Example 1 >

2 is a sectional view of the main portion according to the first embodiment of the repainted coating film according to the present invention. When the undercoat 3 of the recoating film 1 described above is a modified epoxy resin and the top coating film 4 is a urethane resin, it appears as shown in FIG. 2.

The thickness of the undercoat 3 is 90 to 110 μm, and the top coat 4 has a thickness of 30 to 40 μm in one coating and a thickness of 60 to 80 μm in two coatings.

<In accordance with the present invention Repainted Of paint  2nd Example >

3 is a sectional view of the main portion according to the second embodiment of the repainted coating film according to the present invention. When the undercoat 3 of the recoating film 1 described above is a modified epoxy resin, and the top coat 4 is a modified epoxy resin, it appears as shown in FIG. 3.

The thickness of such undercoat 3 is 90-110 micrometers, and the thickness 4 of an upper coating film is 90-110 micrometers.

As described above, those skilled in the art will understand that the present invention can be implemented in other specific forms without changing the technical spirit or essential features. It is therefore to be understood that the above-described embodiments are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

The following drawings, which are attached in this specification, illustrate the preferred embodiments of the present invention, and together with the detailed description thereof, serve to further understand the technical spirit of the present invention, and therefore, the present invention is limited only to the matters described in the drawings. It should not be interpreted.

1 is a flow chart illustrating a repainting method of the old film according to the invention.

Figure 2 is a main portion side cross-sectional view according to the first embodiment of the repainted coating film according to the present invention.

Figure 3 is a main portion side cross-sectional view according to a second embodiment of the repainted coating film according to the present invention.

<Explanation of symbols for the main parts of the drawings>

1: coating film 2: surface: 3: undercoat 4: top coat

Claims (20)

Environmental office facilities and waste treatment facilities that are concerned about corrosion by pollutants, railway bridges, bridges, plant facilities, industrial facilities, cranes, environmental facilities, steel towers, sculptures, etc. By repainting by removing the old film of the same steel structure, Background preparation step of preparing a high pressure washer having a rotating pressure nozzle (S101), the prepared high pressure washer spray pressure of the pressure nozzle 140 ~ 160BAR and the rotational speed of the pressure nozzle 100 ~ 1000rpm to coat the coating film on the surface The step of adjusting the grounding step (S102) to remove the defects and damaged parts of the wide surface from the corners, from side to side and from the top to the bottom and dry the drying time 4 ~ 19 hours depending on the ambient temperature A background adjustment step including; and a background completion step of cleaning (S103); The undercoat preparation step (S201) for preparing the undercoat material of the undercoat, the undercoat work step (S202) for painting the prepared undercoat material and the undercoating step (S203) for drying the finished underpass surface Undercoat coating step (S200); And A top coat preparation step (S301) of preparing a top coat material of the top coat preparation, a top coat operation step (S302) for painting the prepared top coat material surface, a top coat drying step (S303) for drying the finished top coat surface and the In the repainting method of the old film comprising a; top coat painting step (S300) comprising a top coat completion step (S304) of cleaning and finishing the finished top coat surface, The undercoat material of the undercoat coating step (S200) is a polyamine cured two-component modified epoxy resin using a thick film-type modified epoxy resin and aluminum which is coated with a coating thickness of 90 to 110 μm and dried for 16 to 96 hours, and The topcoat material of the top coat coating step (S300) is a coating film, characterized in that the urethane resin mainly composed of acrylic resin and isocyanate which is coated with a coating thickness of 60 ~ 80㎛ by repeated coating twice, and dried for 12 to 84 hours. How to repaint. delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete Environmental office facilities and waste treatment facilities that are concerned about corrosion by pollutants, railway bridges, bridges, plant facilities, industrial facilities, cranes, environmental facilities, steel towers, sculptures, etc. By repainting by removing the old film of the same steel structure, Background preparation step of preparing a high pressure washer having a rotating pressure nozzle (S101), the prepared high pressure washer spray pressure of the pressure nozzle 140 ~ 160BAR and the rotational speed of the pressure nozzle 100 ~ 1000rpm to coat the coating film on the surface The step of adjusting the grounding step (S102) to remove the defects and damaged parts of the wide surface from the corners, from side to side and from the top to the bottom and dry the drying time 4 ~ 19 hours depending on the ambient temperature And a background adjustment step of cleaning; The undercoat preparation step (S201) for preparing the undercoat material of the undercoat, the undercoat work step (S202) for painting the prepared undercoat material and the undercoating step (S203) for drying the finished underpass surface Undercoat coating step (S200); And A top coat preparation step (S301) of preparing a top coat material of the top coat preparation, a top coat operation step (S302) for painting the prepared top coat material surface, a top coat drying step (S303) for drying the finished top coat surface and the In the repainting method of the old film comprising a; top coat painting step (S300) comprising a top coat completion step (S304) of cleaning and finishing the finished top coat surface, The undercoat material of the undercoat coating step (S200) is a polyamine cured two-component modified epoxy resin using a thick film-type modified epoxy resin and aluminum which is coated with a coating thickness of 90 to 110 μm and dried for 16 to 96 hours, and The top coat material of the top coat step (S300) is a one-time coating, the coating thickness of 30 ~ 40㎛ coating, and is a urethane resin mainly composed of acrylic resin and isocyanate to dry for 6 to 72 hours How to repaint the old film. Repaint by removing the old film used in facilities that are exposed to harsh environments such as steel and steel structures and plant and chemical facilities that are exposed to chemical components. In the old film re-coating method consisting of a background adjustment step, a lower coat painting step and a top coat painting step, Background preparation step of preparing a high pressure washer having a rotating pressure nozzle (S101), the prepared high pressure washer spray pressure of the pressure nozzle 140 ~ 160BAR and the rotational speed of the pressure nozzle 100 ~ 1000rpm to coat the coating film on the surface The step of adjusting the grounding step (S102) to remove the defects and damaged parts of the wide surface from the corners, from side to side and from the top to the bottom and dry the drying time 4 ~ 19 hours depending on the ambient temperature A background adjustment step including; and a background completion step of cleaning (S103); The undercoat preparation step (S201) for preparing the undercoat material of the undercoat, the undercoat work step (S202) for painting the prepared undercoat material and the undercoating step (S203) for drying the finished underpass surface Undercoat coating step (S200); And A top coat preparation step (S301) of preparing a top coat material of the top coat preparation, a top coat operation step (S302) for painting the prepared top coat material surface, a top coat drying step (S303) for drying the finished top coat surface and the In the repainting method of the old film comprising a; top coat painting step (S300) comprising a top coat completion step (S304) of cleaning and finishing the finished top coat surface, The undercoat material of the undercoat coating step (S200) and the topcoat material of the topcoat coating step (S300) are coated with 90 ~ 110 μm coating thickness, and polyamine cured type 2 using thick film-type modified epoxy resin and aluminum dried for 16 to 96 hours. A method of repainting the old film, characterized in that the liquid modified epoxy resin. A recoated paint film, which is constructed by the old film recoating method of any one of claims 1, 18 and 19.

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