KR20010060095A - Elastomeric wall coating - Google Patents

Abstract

PURPOSE: An elastic paint composition for constructional materials is provided to make it useable as the finishing material, to have favorable vapour permeability and low water content, to prevent possible cracks and contamination caused by adhesion and to increase washing-resistance of the constructional material. CONSTITUTION: The elastic paint composition comprises 25-55 wt.% of acryl core shell emulsion resin consisting of a seed having a glass transition temperature of -50 to -30 deg.C, 0.03-0.07 micrometers of mean particle diameter; a core having 50-100 of swelling index, another glass transition temperature of -40 to -10 deg.C. and 0.06-0.1 micrometers and gradually increased cross-linkage degree outward from the core; and a shell part having a weight mean molecular weight of 100,000-500,000, the glass transition temperature of -20 to 0 deg.C. and 0.1-0.5 micrometers of mean particle diameter being grafted to the core. The composition further includes 0.5-1.5 wt.% of wax compound, 0.1-0.8 wt.% of organic hollowed filler, 10-30 wt.% of plastic pigment and 1-20 wt.% of commercial additives.

Description

Construction fouling-resistant elastic coating composition {Elastomeric wall coating}

The present invention relates to a fouling-resistant elastic coating composition for construction, and more particularly, by containing an emulsion resin, a wax compound, an organic hollow filler and a plastic pigment of the core shell structure in a conventional elastic coating composition, suitable as a final finish and roll coating It is designed to be able to crack cover even through the coating applied through the film, which not only maintains good water vapor permeability and low moisture moisture content, but also repairs the silk rack of the conventional old film and contaminates it due to the prevention of potential crack and stickiness of new buildings. It relates to a fouling-resistant elastic coating composition for building which minimizes the increase of and improves the wash resistance.

Concrete mortar buildings undergo cracking and transition to coatings over time due to deformation of foundation ground, structural deformation caused by vibration, or surface stress caused by dry shrinkage of building materials. The occurrence of coating cracks causes various problems, and loses the aesthetics and protective functions of the building that can be obtained through the coating. In other words, the crack of the coating film accelerates the aging of the building itself due to the moisture permeation before the appearance problem. However, in the case of the previous elastic coating composition to cope with the problem, there was a problem that it is impossible to use as a finish paint due to the serious contamination caused by the adhesiveness. In particular, the moisture transmitted through the crack during the rainy season is diffused throughout the structure through the capillary to promote the damping of the building and the aging of concrete mortar, reinforcing bars and the like, and lowers the thermal insulation performance. Moistured moisture not only acts as a medium to promote blisters, weathering (Salt Crystalisation), mold propagation, premature aging of building materials, but also enlarges the size of the generated cracks. In addition, the introduction of CO ₂ through cracks promotes the cracking of concrete and the corrosion of rebars.

The most common method of preparing an elastomeric coating composition is to use a plasticizer in the paint formulation. However, in this case, depending on the content of the plasticizer, the tensile elongation variation under a certain temperature condition is severe, and surface elution of the plasticizer becomes a problem when exposed to the long term. In addition, when using a resin with a low glass transition temperature in designing a coating that is resistant to building cracks in an even temperature range, high tensile elongation can be expected, but still suffers from limitations due to low tensile strength and large contamination. . As an alternative to improve the adhesiveness of the elastic coating composition, when the surface UV crosslinking resin is applied, even when exposed to direct sunlight for a long time under the Korean climate, the surface hardening does not proceed sufficiently and the adhesiveness remains undesirably. In another problem, the existing elastic coating composition requires a poor adhesion on the concrete mortar and a work specification that can be obtained only through a separate equipment, and also due to the low water vapor permeability and surface adhesion of the coating film It has been a problem.

As a patent for an elastic coating film for improving such a conventional problem, Japanese Patent Laid-Open Publication No. 4045169 discloses that the glass transition temperature of a polymer emulsion resin composed of a center layer, an intermediate layer and a surface layer is different so that elongation and fouling resistance are low. Although an attempt was made to improve, the technique of resin alone has shown a limit to the improvement of contamination resistance, and Japanese Patent Laid-Open No. 10158545 has not escaped from this context.

As such, resins for general elastic coating compositions are generally synthesized by designing a low glass transition temperature, but in the case of such resins, the elongation at low temperatures can be improved, but the tensile elongation and resilience of the monomers used in the resin are improved. There was a limit to improvement.

Thus, the present invention is to solve the problems as described above, by containing the emulsion resin, the wax compound, the organic hollow filler and the plastic pigment of the core shell structure in a conventional elastic coating composition, it is suitable as a final finish and roll coating By designing the elongation to make crack cover possible through the applied coating film, it not only maintains good water vapor permeability and low moisture content, but also repairs the silk rack of the old coating film and prevents the contamination due to the potential crack prevention and adhesion of new buildings. It is an object of the present invention to provide a fouling-resistant elastic coating composition for construction that minimizes the increase and improves the wash resistance.

The present invention is an elastic coating composition consisting of an emulsion resin, a pigment and a conventional additive,

Seeds having a glass transition temperature of -50 to -30 ° C. and an average particle diameter of 0.03 to 0.07 μm, and a swelling index of 50 to 100 and an average particle of glass transition temperature of -40 to -10 ° C. and 0.06 to 0.1 μm. The core portion having a diameter, the crosslinking degree gradually increasing toward the outside, and the shell portion having a weight average molecular weight of 100,000 to 500,000 and a glass transition temperature of −20 to 0 ° C. and an average particle diameter of 0.1 to 0.15 μm in the core 25 to 55% by weight of grafted and crosslinked acrylic coreshell emulsion resin, 0.5 to 1.5% by weight of wax compound, 0.1 to 0.8% by weight of organic hollow filler, 10 to 30% by weight of plastic pigment and 1 to 20% by weight of conventional additives It is characterized by containing a building antifouling elastic coating composition.

The present invention will be described in more detail as follows.

The present invention is characterized in that the elastic coating composition contains a core shell emulsion resin in which the weight ratio of the core having a constant degree of crosslinking and the shell layer grafted thereon is appropriately controlled. The shell layer may have an appropriate molecular weight in order to improve compatibility with the pigment. It relates to a stain-resistant elastic coating composition for building that can satisfy both the tensile elongation and the restoring force at the same time.

In the present invention, it is characterized by using the emulsion resin of the core shell structure in order to impart excellent adhesion resistance and restoring force to the elastic coating composition, and to improve the wash resistance. The core shell emulsion resin according to the present invention will be described in more detail as follows.

The core-shell acrylic emulsion resin used in the present invention is acrylic acid, methacrylic acid, acrylic acid alkyl ester of 1 to 8 carbon atoms, methacrylic acid alkyl ester of 1 to 4 carbon atoms, based on 100 parts by weight of the resin solid content in the reactor as one step, 5 to 20 parts by weight of at least one or more unsaturated monomers (A) selected from aromatic vinyl compounds and vinyl cyan compounds, 0.1 to 1.5 parts by weight of crosslinking agents, 0.05 to 1.0 parts by weight of grafting agents, 1.0 to 6.0 parts by weight of emulsifiers, and 0.5 to initiators. 2.0 parts by weight and 40 to 60 parts by weight of ion-exchanged water were reacted at 60 to 80 ° C to prepare a seed having a glass transition temperature of -50 to 30 ° C and an average particle diameter of 0.03 to 0.07 μm.

As a second step, in the hydroxy alkyl acrylate and hydroxy alkyl methacrylate of 5 to 8 carbon atoms containing at least 5 to 10 parts by weight of the unsaturated monomer (A) and at least one hydroxyl group based on 100 parts by weight of the resin solid content After adding 2-4 weight part of selected at least 1 type of unsaturated monomer, 0.05-1.0 weight part of crosslinking agents, and 0.05-1.0 weight part of grafting agents to a 1st tank, and mixing it, this mixture is continuously mixed with the said unsaturated monomer (A) 10- 20 parts by weight, 1.0 to 6.0 parts by weight of an emulsifier, 0.5 to 2.0 parts by weight of an initiator and 10 to 20 parts by weight of ion-exchanged water are fed to a second tank to prepare a preemulsion, and 0.1 to 0.8 parts by weight of a reducing agent is added to the reactor. . Thereafter, the pre-emulsion is continuously supplied and reacted at 40 to 60 ° C. to produce a core whose crosslinking degree gradually increases toward the outside.

As a third step, 30 to 85 parts by weight of the unsaturated monomer (A), 1.0 to 6.0 parts by weight of emulsifier, 0.5 to 2.0 parts by weight of initiator, and 15 to 25 parts by weight of ion-exchanged water with respect to 100 parts by weight of a resin solid content of 60 to 80 ° C. And the shell having a glass transition temperature of −20 to 0 ° C. and an average particle diameter of 0.1 to 0.15 μm.

The degree of crosslinking of the core portion is 50 to 100, preferably 65 to 80, and the glass transition temperature is -40 to -10 deg. C and 0.06 to 0.1 m based on the degree of swelling in the solvent. It has an average particle diameter.

In addition, the graft efficiency of the shell grafted to the core portion is 10 to 50% by weight, preferably 20 to 40% by weight relative to the shell monomer used in preparing the core shell emulsion resin is used. At this time, when the graft efficiency is less than 10% by weight, the adhesiveness of the resin is increased to reduce the stain resistance, and when the graft efficiency is higher than 50% by weight, the tensile elongation is deteriorated. In particular, the shell monomer grafted with the reactor of the core portion has a weight average molecular weight of 100,000 to 500,000, preferably 150,000 to 230,000.

In the present invention, 25 to 55% by weight of the emulsion resin of the core shell structure is used with respect to the entire elastic coating composition, preferably 35 to 45% by weight. At this time, if the use content is less than the above range, there is a problem that elongation is sharply dropped, while if the above used range, the adhesiveness increases.

In addition, the pigment volume ratio (volume ratio of the color pigment and the extender pigment) with respect to the total elastic coating composition of the present invention is 15 to 45% by weight, preferably 25 to 35% by weight, the adhesive when the pigment volume ratio is less than 15% by weight There is a problem that is impossible to improve, while the elongation is extremely poor if it exceeds 45% by weight.

Particularly, in the present invention, for the purpose of improving the stain resistance of the elastic coating composition, a mixture with a high polymer having a high glass transition temperature is introduced, and a plastic pigment (for example, H9181) is used for this purpose. Unlike other emulsion resins, the plastic pigments can gently control the sharp drop in elongation due to the increase in the content of the resin component having a high transition temperature, and are effective in improving the adhesiveness. The hard polymer has a glass transition temperature of 90 to 110 ° C. and a weight average molecular weight of 100,000 to 1,000,000, and for example, one selected from 400, 500, 700, and 1,000 nm depending on the particle diameter. Plastic pigments used in the present invention is used in 10 to 30% by weight, preferably 15 to 25% by weight relative to the total elastic coating composition. When the content of the plastic pigment used in the above is out of the above range, the coating film formation is insufficient to reduce the coating film properties.

In addition, in the present invention, in order to maximize the stain resistance, the wax compound is used in an amount of 0.5 to 1.5% by weight, and through the surface orientation of the wax compound, it is possible to improve the adhesiveness and thereby improve the stain resistance. The reason for limiting the use amount of the wax compound in the present invention is because of the ease of paint production.

In addition, in the present invention, there is a feature of using an organic hollow filler in the elastic coating composition, which has a very small specific gravity and isobutane gas is filled therein, the particle size is 30 ~ 90 ㎛. The organic hollow filler serves to increase the glass transition temperature of the surface of the coating film without inducing elongation by inducing the surface orientation of bulky particles having a high glass transition temperature, thereby improving fouling resistance and wash resistance. The organic hollow filler may be selected from polyvinyl chloride, polyvinylidene fluoride, polyvinylidene chloride, polyvinyl fluoride, and polyvinyl n-butylate, and polyvinylidene chloride may be preferably used. In the organic hollow filler used in the present invention, 0.1 to 0.8% by weight may be used with respect to the elastic coating composition. If the content is less than 0.1% by weight, there is a problem that thickening of the coating film and silk racking are impossible during roll coating. On the other hand, rather than 0.8% by weight, a decrease in pollution resistance is found.

In addition, in the elastic coating composition of the present invention, white pigments and sieving pigments as distilled water, wetting agents, dispersing agents, antifoaming agents, solvents, and pigments, and co-solvents, preservatives and thickeners are used in the amounts contained in conventional elastic coating compositions. The solvent used in the present invention includes ethylene glycol, ester alcohol and the like.

On the other hand, the cover of the structure crack is unnecessary in terms of stability of the building, but the cover of the silk rack that can prevent moisture permeation of the fatal to the exterior of the building and aging of the building is essential. Until now, it is difficult to freely control the rheological properties of the paint because it requires the dry film thickness of the thick film for the crack cover in practical use, so that it is not easy to obtain a sufficient film thickness for crack prevention through roll or brush work. That is, the existing bone-type elastic waterproof coating composition was uneconomical because there is a problem that the coating process and the construction cost of several times increase. In contrast, the elastic coating composition according to the present invention is endowed with crack resistance in a state having a practically sufficient finish thickness while having a low coating film thickness.

The elastic coating composition of the present invention as described above can be applied to the building without a separate pretreatment process for the silk rack found during the repair coating of the building, and does not expose the crack when the building cracks after new coating It is an elastic paint that maintains the beautiful appearance of the building and prevents the penetration of moisture, which adversely affects the aging of building materials, thereby extending its durability. It is used as an elastic waterproof primer of and can prevent the occurrence of cracks of general paints applied subsequently.

Hereinafter, the present invention will be described in detail with reference to the following Examples, but the present invention is not limited by the Examples.

Example 1 and Comparative Examples 1-5

Next, an elastic coating composition was prepared in the same composition and content as Table 1 below.

week)

1) Wetting agent, air product company

2) Dispersant, Sannovco Korea

3) Antifoam, BW

4) White Pigment, Tioxide

5) Calcium Carbonate, Woojin Chemical

6) Langer's Wax Compound

7) polyvinylylene chloride, allobel

8) H9181, Korea Chemicals

9) Texanol, Eastman

10) thiazole derivatives, door yarn

11) Urethane Thickener, Rohm and Haas

12) Urethane Thickener, Rohm and Haas Inc. (Effective Thickener in High Shear Velocity)

The physical properties of Example 1 and Comparative Examples 1 to 5 prepared above were measured by the following method, and the results are shown in Table 2 below.

[Test Methods]

1. Tensile Elongation: Measured according to ASTM D 4541 method.

2. Tensile strength: measured according to ASTM D 4541 method.

3. Restoration force: After 3 cycles of 100% tension at a rate of 10 mm / min, the restoration length was measured.

4. Pollution Resistance: Measured using self designed contaminant solution contamination and writing instrument contamination test method.

5. Thickness: measured using DFT measurement method.

6. Wash resistance: measured using KSM 5000-3351 method.

In the results of Table 2, in Comparative Example 1, the coating composition using a resin having a low glass transition temperature alone was insufficient in tensile strength and extremely poor in stain resistance and wash resistance. To this end, when the pigment volume ratio is increased, mechanical properties, in particular, elongation and resilience are drastically reduced. In addition, in Comparative Example 2, in order to overcome the poor fouling resistance found by using the resin having a low glass transition temperature in Comparative Example 1 alone, a high polymer of high glass transition temperature was used. It also brought about a sharp drop in elongation. In comparison, when the plastic pigment of Comparative Example 3 was increased, the elongation was gradually decreased and the tensile strength was maintained. In addition, in the case of Comparative Example 4, since the wax compound and the organic hollow filler were not used, inferior physical properties in fouling resistance, wash resistance, and thick film performance were exhibited.

The elastic coating composition of the present invention is designed with mechanical properties of 180% tensile elongation and 2.1kgf / sq.mm tensile strength to exhibit sufficient crack resistance under domestic climatic conditions, and the crosslinked corel emulsion resin used in the present invention is It has excellent resilience due to local elongation and crack movement in a wide temperature range such as low temperature. In addition, as well as fouling resistance and wash resistance, it has a good water vapor permeability, low moisture content can contribute to the long-term improvement of the building.

As described above, by containing the emulsion resin, the wax compound, the organic hollow filler and the plastic pigment of the core shell structure in the elastic coating composition of the present invention, the paint can be applied to the building without a separate pretreatment process, beautiful building Appearance can be extended and durability can be extended, it can be used as an elastic waterproof primer in the parts that require waterproofing, such as cracks in the apartment floor or the upper and lower parts of the window frame, it is possible to prevent the occurrence of cracks of the general coating applied subsequently, Application can also be extended as a water-soluble top coat of the bone-tile elastic waterproofing coating applied to the solvent two-component urethane.

Claims (4)

In the elastic coating composition consisting of an emulsion resin, a pigment and a conventional additive, Seeds having a glass transition temperature of -50 to -30 ° C. and an average particle diameter of 0.03 to 0.07 μm, and a swelling index of 50 to 100 and an average particle of glass transition temperature of -40 to -10 ° C. and 0.06 to 0.1 μm. The core portion having a diameter, the crosslinking degree gradually increasing toward the outside, and the shell portion having a weight average molecular weight of 100,000 to 500,000 and a glass transition temperature of −20 to 0 ° C. and an average particle diameter of 0.1 to 0.15 μm in the core 25 to 55% by weight of grafted and crosslinked acrylic coreshell emulsion resin, 0.5 to 1.5% by weight of wax compound, 0.1 to 0.8% by weight of organic hollow filler, 10 to 30% by weight of plastic pigment and 1 to 20% by weight of conventional additives Building pollution-resistant elastic coating composition, characterized in that it contains. According to claim 1, wherein the shell portion of the cross-linked core-shell emulsion resin is 10 to 50% by weight in the shell monomer graft cross-linking elastic coating composition, characterized in that the core portion. According to claim 1, wherein the organic hollow filler is an antifouling elastic coating composition for building, characterized in that selected from polyvinyl chloride, polyvinylidene fluoride, polyvinylidene chloride, polyvinyl fluoride and polyvinyl n-butylate. According to claim 1, wherein the elastic coating composition is a stain-resistant elastic coating composition for building, characterized in that the pigment volume ratio of 15 to 45% by weight.