KR100949599B1 - Waterproofing method with water reactive polyurethane resin compounds - Google Patents

Abstract

The present invention provides a two-component polyurethane-based resin composition comprising a main component and water having a latent hardener and a latent hardener decomposition catalyst added to a urethane prepolymer as a curing agent, and waterproofing a coating film of a floor or a wall such as a roof of a building using the same. It relates to a construction method, specifically, repairs and repairs damaged parts such as cracks on the surface with an aqueous polyurethane-cement resin mortar adhesive that does not use an organic solvent, and applies an aqueous epoxy resin primer to the base material and the coating layer. To increase the adhesion to the water, and to form a water-curable polyurethane coating film waterproof layer using water as a curing agent, and then to form a top coat layer by coating an aqueous acrylic-urethane paint to decorate the aesthetics, the urethane coating film waterproof Followability to cracks in the lower limbs, which are characteristic only in the process Beam and relates to a coating film waterproofing method eco-friendly polyurethane that can be fundamentally prevented by a sick building syndrome caused by emission of an organic compound after construction.

Description

Two-component urethane resin composition and urethane coating waterproofing method using same {Waterproofing Method with Water Reactive Polyurethane Resin Compounds}

The present invention relates to a method for preparing a hydrocurable polyurethane-based resin composition which can block indoor inflow of volatile organic compounds (VOCs), which has been recently caused by a new house / school syndrome, and a polyurethane coating waterproofing method using the same.

Polyurethane resins containing a polyurethane prepolymer having an isocyanate group at its end as a hardening component are classified into a two-part type which is cured by mixing a one-component type cured by moisture in the air and a curing agent containing a curing component reacting with isocyanates such as polyols. do.

In general, two-component type is mainly used in paints, adhesives, or sealants that foaming does not occur well and that can be cured in a short time regardless of the curing thickness.

However, in the conventional two-component polyurethane resin composition, a large amount of non-reactive diluent such as toluene and xylene is added to adjust the workability after mixing the main body and the curing agent, and it is difficult to balance the working time (housework time) and the curing property. There is a problem that a hazardous metal catalyst such as lead dibutyl octylate (DBTDL) must be used in order to suppress the point and foamability.

On the other hand, roofs, verandas and corridors of buildings are generally waterproofed to prevent intrusion of water by rainwater or groundwater.

Currently, the roof waterproofing method currently used is urethane coating method, FRP coating method, vinyl chloride sheet method, synthetic rubber sheet method, ethylene vinyl acetate sheet method, modified asphalt room temperature method, modified asphalt thermal method, asphalt thermal method. , Modified asphalt torch method, etc., and veranda and corridor waterproof method include urethane coating method, FRP coating method, polymer-cement type coating method, asphalt thermal method, permeability coating, mortar waterproofing, vinyl chloride sheet method, modified asphalt room temperature The process method and the ethylene vinyl acetate type sheet method are used.

Of these waterproofing methods, the waterproofing method using asphalt has been widely used in view of economic aspects until now, but in recent years, a polyurethane-based resin is applied to the treated surface in terms of performance and durability. Urethane coating waterproofing method for forming a waterproof coating is increasing rapidly.

Conventional urethane coating waterproofing method repairs cracks with epoxy resin mortar containing solvents such as BGE and DGE on the surface of concrete on rooftop and porch / corridor, and then contains polysilicon containing large amount of organic solvents such as xylene and toluene. A urethane primer was applied to a thickness of 50 μm, and a solvent-based polyurethane middle coat containing xylene and toluene was applied to a thickness of 2 to 3 mm, and then xylene and toluene were contained. A method of finishing acrylic-urethane top coats with a thickness of 70 to 80 μm has been mainly used.

Therefore, if waterproofing is performed by the above method, if cracks are present on the rooftop and porch / corridor concrete floor, unreacted polyurethane resin or solvent flows into the cracks during the ground treatment and undercoating and intermediate coating. Volatile organic compounds are introduced into the room, causing major social problems such as new home / school syndrome. In particular, it is recognized that most of these volatile organic compounds are released within a week after the construction of waterproofing materials. [Influence of indoor school air quality on elementary school students' cognitive function, Vol. 19, No. 1, 2007 (3, 2007) Monthly), 73–80], when the window is unopened even after one month of construction, it is found to exceed the upper limit of TVOC (400ug / m3).

Therefore, the government recently implemented the new indoor air quality management law, which was newly revised from May 2004, to formaldehyde (HCHO), benzene, toluene, ethylbenzene, xylene, styrene, para- It was announced to measure the release amount of dichlorobenzene over 60 days 3 days before moving in and to announce the results.

The present invention has been proposed to improve the problems of the conventional urethane film waterproofing method, the phenomenon that the curing reaction is delayed in the one-component urethane film waterproofing agent and the two-component urethane film waterproofing agent when the humidity is low and the thickness of the coating film is thick Disclosed the VOCs problem caused by the use of organic solvents and discloses a method for producing a water-curable polyurethane coating film waterproofing agent using water as a curing agent as a polyurethane coating waterproofing agent for construction, excellent mechanical properties and foaming does not occur on the surface of the coating film, and By using this, it is possible to fundamentally prevent the generation of volatile organic compounds during waterproofing of roof and porch / corridor, and to provide eco-friendly urethane coating waterproofing method that can prevent the delay of new construction period due to the amount of emitted organic compounds. Its purpose is to.

In order to solve the above-mentioned problems, a two-component urethane resin composition comprising a main agent to which a latent hardener and a latent hardener decomposition catalyst are added to a urethane prepolymer and a curing agent made of water is provided.

In addition, in the present invention, using a water-based urethane resin mortar adhesive consisting of a polyurethane-cement resin composition to form a surface pulp layer for repairing the cracked and broken portions formed on the concrete surface, and the bottom coat for concrete composed of an aqueous epoxy resin composition An adhesive layer forming step of applying on the surface pulp layer, a water-based urethane waterproofing agent consisting of a water-curable polyurethane-based resin composition using water as a curing agent, a waterproof layer forming step of applying on the adhesive layer, and an aqueous acrylic-urethane-based resin composition There is provided an environmentally friendly urethane coating waterproofing method using a two-component urethane resin composition consisting of a coating layer forming step of applying a coating on the waterproof layer.

The present invention configured as described above can solve the occurrence of volatile organic compounds (VOCs), which is a major problem in urethane resin compositions because water is used as a curing agent, and uses a latent hardener and a latent hardener decomposition catalyst. Thus, the physical properties and the foaming resistance of the cured product produced from the water-curable urethane resin composition can be significantly improved.

In addition, the water-curable urethane resin composition disclosed in the present invention can be used for the production of various polyurethane-based paints, adhesives, sealing agents, using a water-based urethane coating film waterproofing agent, an aqueous urethane resin mortar adhesive, an aqueous epoxy primer, When the urethane coating waterproofing is performed in a system having an aqueous acrylic-urethane top coat, it becomes an environmentally friendly urethane coating waterproofing method that can fundamentally block the release of volatile organic compounds.

Hereinafter, with reference to the configuration illustrated in the drawings to describe the specific configuration and operation of the present invention.

The water-curable polyurethane coating film waterproofing agent of this invention consists of a main body (A) and a hardening | curing agent (B), and is a 2-component polyurethane resin characterized by using water as a hardening | curing agent.

In this two-component polyurethane-based resin composition, the main ingredient (A) is prepared through the urethane prepolymer synthesis step (A) and the urethane resin composition combination step (B).

(A) Synthesis step of urethane prepolymer

The urethane prepolymer is a polyisocyanate compound (a) and a polyol compound (b) using a polyisocyanate compound (a) having two or more isocyanate groups per molecule and a polyol compound (b) having two or more hydroxyl groups per molecule. A compounding ratio is calculated by NCO group / OH group (equivalent ratio), it mix | blends about 1.2-2.5, it is made by making it react at 50-130 degreeC for 5 to 15 hours. The isocyanate group (-NCO group) content of the urethane prepolymer solution thus prepared is adjusted to be 0.5 to 6.0% by weight. Only when the NCO group content is adjusted in this range, physical properties as a paint, an adhesive, and a sealant using the water-curable polyurethane-based resin composition can be secured, and a risk of free isocyanate compound release can be prevented.

Examples of the polyisocyanate compound (a) used in the urethane prepolymer synthesis step of the main ingredient (A) include XDI, TDI, MDI, TMXDI, TMHDI, NDI, H ₆ XDI, H ₁₂ MDI, HDI, IPDI, and NBDI. Or you may mix and use 2 or more types. Of these, tolylene diisocyanate (TDI) and diphenylmethane-diisocyanate (MDI) are preferable, because tolylene diisocyanate (TDI) is used, and the viscosity of the prepared urethane prepolymer is low and easy to handle. This is because the price is lower, and the use of diphenylmethane diisocyanate (MDI) is less expensive and less harmful to the human body.

As the polyol compound (b) used in the urethane prepolymer synthesis step of the main ingredient (A), known polyether polyols, polyester polyols, polycarbonate polyols and the like may be used alone or in combination of two or more thereof. Among them, polyether polyol is excellent for elongation and strength of cured product and less property deterioration after water immersion. Therefore, polyether polyol is good for coating or sealing agent, and polyester polyol and polycarbonate polyol are excellent for adhesive because of excellent adhesive strength of cured product.

(B) urethane resin composition combination step

In the urethane resin composition combining step (b), a latent hardener (c) and a latent hardener decomposition accelerator (d) are used in the urethane prepolymer solution prepared in the urethane prepolymer synthesis step (a).

The latent hardener (c) constituting the subject (A) includes oxazolidine-based, ketamine-based, aldimine-based and enamine-based latent curing agents, among which N-hydroxy having at least one oxazolidine ring in a molecule thereof. The oxyoxazolidine compound is good because it is excellent in foaming resistance and storage stability. Specific examples of N-hydroxyalkyloxazolidine compounds include 2-isopropyl-3- (2-hydroxyethyl) oxazolidine, 3- (2-hydroxyethyl) oxazolidine, 2- (p-methok Ciphenyl) -3- (2-hydroxyethyl) oxazolidine, 2- (2-methylbutyl) -3- (2-hydroxyethyl) -5-methyloxazolidine, etc. are mentioned.

The optimum addition amount of the latent hardener used in the urethane resin composition combining step (b) of the main body (A) is 0.5 to 5.0% by weight of the total weight of the urethane prepolymer (a). When the amount of latent hardener added is in the range of 0.5 to 5.0% by weight, the cured product properties of the urethane resin composition are maintained well, and the reaction of the NCO group and the latent hardener (c) and the hardener (B, water) contained in the main component (A) It is made chemically equivalent and foaming can be suppressed. The reason why foaming is suppressed during curing of the urethane resin composition is that the cleavage reaction of the latent curing agent occurs preferentially by forming the amine group and the hydroxyl group by the moisture present in the system after the main body (A) and the curing agent (B) are mixed. It is considered that foaming due to urea formation reaction of water and isocyanate (-NCO group) is suppressed.

The present invention is also characterized in that the latent curing agent decomposition catalyst (d) is added in the urethane resin composition combining step (b) of the subject (A). As the latent curing agent decomposition catalyst (d), an organic acid or silyl ester is used.

The organic acid is not limited as long as it is an organic acid having an acid property, but an organic carboxylic acid is preferable. Examples of the organic carboxylic acid include octylic acid, 2-ethylnucleic acid, neodecanoic acid, and the like. Examples of the silyl ester catalyst include tris- (trimethylsilyl) phosphate, tris- (triphenylsilyl) phosphate, and mono- (trimethylsilyl). ) Phosphites, monosilyl esters, disyryl esters, and trisyryl esters thereof. These may be used individually by 1 type, and may mix and use 2 or more types. As for the addition amount of an organic acid or a silyl ester, 0.1-3.0 weight% of the total mass of a hardening | curing agent (E) is suitable.

The reason for using the latent curing agent decomposition catalyst (d) in the main body (A) is that the water and the main (A) present in the system when the organic acid or the cyclyl ester are mixed with the main body (A) as a curing agent (B). The latent curing agent (c) contained in the reaction promotes a cleavage reaction to generate an amine group (-NH 2) and a hydroxyl group (-OH), so that the water present in the system is an isocyanate group (-NCO group). This is because it is possible to prevent the formation of urea bonds by reacting with), thereby suppressing foaming and maintaining a balance between pot life and curability.

The urethane resin composition combining step of the subject (A) disclosed in the present invention is functional according to the use (paint, adhesive, sealing agent) of the urethane resin composition in addition to the latent curing agent (c) and the latent curing agent decomposition catalyst (d). In order to reinforce this, generally known fillers, plasticizers, curing catalysts, pigments, thixotropic agents, dispersants, curing catalysts and the like can be used in an appropriate amount.

The curing agent (B) disclosed in the present invention refers to general tap water which can be used as drinking water, and the amount of curing agent is used in terms of the physical properties (modulus, elongation, tensile strength, etc.) and heat stability of the cured product obtained from the urethane resin composition. It is preferable that the equivalent ratio [isocyanate group / active hydrogen group] of the sum total of the active hydrogen groups which an isocyanate group and an active hydrogen compound has is 0.8-1.5. Therefore, the appropriate amount of water as the curing agent (B) is preferably 10 to 30% by weight of the total weight of the main body (A). The optimum compounding amount of the curing agent (B) is determined according to the NCO group content contained in the main agent (A) and the amount of the latent hardener (c) and the latent hardener (d) added, and the amount of water is less than 10% by weight. If the main body is cured in an unreacted state or there is less urethane bond formed by the polyurethane resin composition, there is a risk that the physical properties of the cured product will be lowered. When the water content is 30% by weight or more, free water is excessive in the cured product. Exists and the physical property of a hardened | cured material falls.

On the other hand, the urethane waterproofing method according to the present invention, as shown in [FIG. 1], the surface pulp layer forming step (S100) and the adhesive layer forming step (S300), the waterproof layer forming step (S500) and the coating layer forming step (S700) It consists of.

First, the surface pulp layer forming step (S100) is intended to uniformly apply the thickness of each coating layer to be repaired and cracks on the surface to be treated, using a water-based polyurethane-cement resin mortar adhesive prepared To recover the damaged parts.

The water-based polyurethane-cement-based resin mortar adhesive used in the surface pulp layer forming step of the present invention is an organic solvent as disclosed [eco-friendly polyurethane-cement composition, patent application No. 10-2007-0114081] disclosed by the same applicant of the present invention. Mixed dry mortar (C) mixed with cement and sand / gravel in a mixed solution of water (a) composed of polyisocyanate compounds containing no polyisocyanate and curing agent (B) composed of water and polyol compounds It is preferable that the mixing ratio of the polyurethane-based resin used to prepare the polyurethane-cement resin mortar is 10 to 30% by weight of the total weight of the polyurethane-based resin mortar (polyurethane resin + dry mortar). When the polyurethane-based resin is mixed at less than 10% by weight, the workability and adhesive strength with the substrate are not secured in the polyurethane-based resin mortar. When the content of the resin is 30% by weight or more, the flowability is large and the vertical surface of the damaged part is repaired. Becomes difficult.

The basic combination of dry mortar is composed of cement and sand, but in order to improve the workability of polyurethane-based resin mortar, dry mortar mixed with concrete admixtures, dispersants, thickeners, pigments, functional fillers, and the like may be used. In addition, the mixing of the polyurethane resin mortar disclosed in the present invention can be carried out in a conventional method using a known mortar mixer, concrete mixer, asphalt mixer, etc., the method of construction of the polyurethane resin mortar also by a conventional resin mortar construction method can do.

When the surface pulp layer forming step (S100) is completed, the surface pulp layer curing step (S200) for about 1 to 3 days to form its own maximum strength. The period of the surface pulp layer curing step (S200) may be modified and applied depending on the temperature and humidity and the thickness of the surface pulp layer 100.

When the surface pulp layer curing step (S200) is completed, that is, the adhesive layer forming step (S300) is carried out, the adhesive layer forming step (S300) is a self-waterproof function, as well as the bonding force between the surface pulp layer 100 and the waterproof layer 200. In order to increase the thickness, the surface is applied in a rolling manner so as to have a thickness of about 50 μm. The thickness of the adhesive layer 200 is not limited thereto and may be variously modified according to an application environment.

The adhesive layer 200 is implemented in the form of using an amine curing agent in a water-soluble epoxy resin. The water-based epoxy resin composition used by the present invention uses a water-soluble amine hardener for the water-soluble epoxy resin (Kukdo Chemical Co., Ltd., YD-011 system) currently used in Korea.

처럼 에폭시기를 2개 이상 가진 축합수지로, 밑의 (화학식1)과 같이 에피클로르히드린에 비스페놀A를 알칼리성으로 반응시켜 생성된 주제성분에 아민계나 폴리아민계, 폴리설파이드계, 유기산 무수물 등의 경화제를 첨가하여 반응시킴으로써 에폭시기의 고리가 열려 부가 중합한 형태로 이루어진다.More specifically, general epoxy resin

As a condensation resin having two or more epoxy groups, a curing agent such as an amine, a polyamine, a polysulfide, or an organic anhydride to the main component produced by alkali reaction of bisphenol A to epichlorohydrin as shown in the following formula (1). By adding and reacting, a ring of an epoxy group is opened to form a polymerization product.

Formula 1-

The epoxy resin-based waterproof / anticorrosive material is divided into a solvent type and a water-soluble, since the solvent-type epoxy resin has a problem that the organic solvent is released after construction as described above, the water-soluble epoxy resin is used in the present invention.

The water-soluble epoxy resin is particularly suitable for places where moisture and condensation occur in summer when the humidity is high.

When the adhesive layer forming step S300 is completed, the adhesive layer 200 is stacked on the surface pulp layer 100 as shown in FIG. 2.

Thereafter, through the adhesive layer curing step (S400) for 4 to 24 hours, the time required for the adhesive layer curing step (S400) is to be changed according to the temperature, humidity, adhesive layer 200 thickness as in the surface pulp layer curing step (S200). Can be.

When the adhesive layer curing step (S400) is completed in this way, the waterproof function as a main function is performed, that is, the waterproof layer forming step (S500), the rolling method so that the liquid material to the thickness of about 2 to 3mm on the adhesive layer 200. It is made in the form of applying. In this case, the thickness of the waterproof layer 300 is not limited thereto and may be variously modified according to an application environment.

When the waterproof layer forming step (S500) is completed as shown in FIG. 2, the waterproof layer 300 is laminated on the adhesive layer 200.

On the other hand, the composition constituting the waterproof layer in the present invention is a polyurethane-based using water as a curing agent, unlike the polyurethane resin generally used as the "eco-friendly polyurethane waterproof flooring resin composition" disclosed and disclosed by the same applicant of the present invention It is an eco-friendly waterproof flooring material that does not use organic solvents at all as a waterproofing agent.

In more detail, it basically consists of a two-component form of the main (D) and the curing agent (E), wherein the main (D) is a first polyol compound having two or more hydroxyl groups per molecule and two or more per molecule It is the form which made the aromatic polyisocyanate compound which has an isocyanate group react.

As the first polyol compound, a polyether polyol having a number average molecular weight of 2000 to 5000 and containing two or three hydroxyl groups is used. Among them, an alcohol compound having two or three hydroxyl groups is used as an initiator and propylene oxide is additionally polymerized. Polyether polyols such as polypropylene glycol obtained by use of

For reference, it is preferable to use diphenylmethane-4, 4-diisocyanate (MDI) which is less harmful to the human body as the aromatic polyisocyanate compound.

In addition, the filler included in the subject is added to improve the mechanical properties of the waterproof layer, and selects two kinds of fillers such as calcium oxide, magnesium oxide, and aluminum silicate, which are known to have foam suppression effect.

The amount of the filler added is preferably 5 to 25% by weight based on 100% by weight of the total main composition. This is because if the content is less than 5% by weight, the mechanical properties of the final cured product are lowered, and if the content is more than 25% by weight, the viscosity of the main composition is increased to reduce the defoaming effect as well as to reduce workability and precipitate the filler.

The curing agent (E) of the present invention contains water as a main component, the content of which is contained 50 to 90% by weight relative to 100% by weight of the total curing composition. If the content of water is less than 50% by weight, there is a problem that the curing rate is slow and the final physical properties are lowered, and when the content of water exceeds 90% by weight, there is a concern that the curing agent is frozen during the winter season.

Thereafter, the waterproofing layer curing step (S600) for curing the waterproofing layer 300 is performed, which is also made for 1 to 3 days depending on the temperature and humidity of the waterproofing layer.

When the waterproof layer curing step (S600) is completed, the coating layer forming step (S700) is carried out. The coating layer forming step (S700) is a process of forming a coating layer having a self-waterproof function while protecting the waterproof layer from external factors such as ultraviolet rays. It is made by the rolling method so that a liquid material may be about 70-80 micrometers thick. The thickness of the coating layer 400 is not limited thereto, but may be variously modified and implemented according to an application environment.

The coating layer 400 uses an aqueous acrylic-urethane-based resin composed of a generally used aqueous acrylic base and an isocyanate-based curing agent, which is also environmentally friendly because it can suppress the use of a solvent as much as using aqueous. It was highlighted.

In addition, the top coat used by this invention uses what is commonly used in Korea as an aqueous acryl-urethane type resin comprised from an aqueous acryl-type main material and an isocyanate type hardener.

According to the steps S100, S200, S300, S400, S500, S600, and S700 described above, the surface pulp layer 100 and the adhesive layer on the surface C to be treated as shown in FIG. The entire coating layer is formed in such a manner that the 200, the waterproof layer 300, and the coating layer 400 are sequentially stacked.

When the coating layer forming step (S700) is completed through the coating layer curing step (S800) to cure the coating layer, which takes about one week depending on the climate, temperature, humidity, coating layer thickness.

In the present invention, the surface pulp layer 100 is formed using an aqueous polyurethane-cement resin mortar containing no volatile organic compound, the adhesive layer 200 is formed using an aqueous epoxy resin, and the waterproof layer 300 is a hardener. Forming a polyurethane-based resin composition containing water as a main component, the coating layer 400 is formed of an aqueous acrylic-urethane resin, it is possible to minimize the amount of air emissions of organic components after the construction process and construction.

For reference, the coating waterproofing method is greatly influenced by the lower limbs, causing a large thickness variation and causing anxiety about the waterproof performance. On the other hand, while the sheet waterproofing method has less influence on the underfoot condition, the problem of leakage at the joint part is discussed. Therefore, when the sheet method and the coating method are used together, water leakage at the joint portion can be prevented, thereby ensuring a more reliable waterproof performance. In addition, a method of preventing the swelling of the waterproof layer due to evaporation of moisture contained in concrete frequently used in the urethane coating method by using a urethane coating film method and a ventilation buffer sheet method is widely used. Recently, the roof coating film waterproofing method has been combined with the high reflectivity thermal shielding method and the roofing greening method.

Therefore, the present invention also includes a generally known high reflectivity heat shielding method, a rooftop greening method, and a sheet composite waterproofing method using the above-described resin mortar coating medium coating for base treatment.

1 is an overall process diagram of the present invention.

Figure 2 is a schematic diagram showing a state in which the surface of the surface layer and the adhesive layer, the waterproof layer and the coating layer sequentially laminated on the surface to be treated.

Claims (7)

The urethane prepolymer is added with a latent hardener and a latent hardener decomposition catalyst, A hardener consisting of water, The latent hardener is at least one of oxazolidine latent hardener, ketimine latent hardener, aldimine latent hardener, enamine latent hardener is added 0.5 to 5.0% by weight of the total weight of the urethane prepolymer, The latent hardener decomposition catalyst is a two-component urethane resin composition, characterized in that at least one of the organic acid or the cyryl ester is added 0.1 to 3.0% by weight of the total weight of the urethane prepolymer. delete delete The method according to claim 1, Water applied as the curing agent is a two-component urethane resin composition, characterized in that 10 to 30% by weight based on 100% by weight of the main body. The method according to claim 4, The urethane resin composition is a two-component urethane resin composition, characterized in that applied to at least one of paints, adhesives, sealing agents. Surface pulp for repairing cracked and damaged portions formed on the concrete surface by using an aqueous polyurethane resin mortar adhesive composed of a polyurethane-cement resin composition using a two-component urethane resin composition using water as a curing agent. The layer forming step, An adhesive layer forming step of applying a base material for concrete composed of an aqueous epoxy resin composition on the surface pulp layer, A waterproof layer forming step of applying an aqueous urethane waterproofing agent composed of a water-curable urethane resin composition using water as a curing agent on the adhesive layer; Eco-friendly urethane waterproofing method, characterized in that consisting of a coating layer forming step of applying an aqueous coating consisting of an aqueous acrylic-urethane-based resin composition on the waterproofing layer. The method according to claim 6, The main composition of the waterproof layer is a filler for improving the mechanical properties of the waterproof layer is added, the filler is an environmentally friendly urethane waterproof method, characterized in that two kinds of calcium oxide, magnesium oxide, aluminum silicate is selected and used.

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