JP2023005811A - Coat formation method - Google Patents

Abstract

To provide a coat formation method for securely applying a homogenous dotted pattern by roller coating on an existing wall surface at a construction site, etc.SOLUTION: The invention is a coat formation method by applying a coating material by roller coating at least after applying an intermediate coating material on a wall surface. Synthetic resin emulsion (m) and light-weight coloring particle (n) having bulk density of 1.0 g/ml or less and average particle diameter of 0.01 to 1 mm are essential components of the coating material. The coating material containing 0.1 to 50 parts by weight of the light-weight coloring particle (n) is used for a solid content of 100 parts by weight of the synthetic resin emulsion (m). Glossiness is different between a coat of the intermediate coating material and a coat of the coating material.SELECTED DRAWING: None

Description

The present invention relates to a novel film forming method.

BACKGROUND ART Conventionally, inorganic building materials such as siding boards and ALC boards have been widely used as materials for constructing walls of buildings. In the coating of such inorganic building materials, a method of applying a speckled pattern to the surface is adopted in order to enhance the design. For example, Patent Literature 1 describes a method of forming a speckled pattern by using a colored coating material adjusted to a specific viscosity and spray coating while controlling the pattern, discharge amount, etc. during coating. Further, Patent Document 2 describes a method of unevenly applying a colored coating material different in color from the base coating material after coating the base coating material.

However, all of these methods relate to coating methods in factories, and spatter coating is applied while mechanically controlling a colored coating material to impart a speckled pattern. Inorganic building materials installed as wall materials at construction sites need to be repainted due to deterioration over time. At present, it is difficult to stably obtain a spotted pattern having a size of 1.5 mm, and the method lacks practicality.

On the other hand, there is also known a method of imparting a speckled pattern to an inorganic building material by applying a topcoat material in which an aggregate such as silica sand or mica is dispersed in a resin liquid. According to such a method, it is possible to obtain a speckled pattern of a desired size by setting the particle size of the aggregate used. For example, Patent Literature 3 describes a method of applying a clear topcoat material containing a flat colored material such as mica onto a laminated multicolored pattern coating film.

JP-A-3-186381 Japanese Utility Model Laid-Open No. 4-77440 Japanese Patent No. 6180678

However, when a roller is used as a coating tool in the coating of topcoat materials containing aggregates such as silica sand and mica as described above, the aggregates tend to gather together on the surface to be coated, and the spot pattern is uneven. It is difficult to obtain a uniform speckled pattern.

In addition, in the above-mentioned Patent Document 3, as a specific example of the topcoat material, a matte type topcoat material containing colored mica, extender pigment, etc. is described. is stated. However, in such a coating method, if there is an uncoated area of the topcoat material (an area where the topcoat material is not coated), it is difficult to identify the area, and subsequent repair may be difficult.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a method of forming a film that reliably imparts a uniform spotted pattern to an existing wall surface at a construction site or the like by roller coating. is.

As a result of intensive studies to achieve the above object, the present inventors have found that after painting at least a specific intermediate coating material on the wall surface, a specific topcoat containing lightweight colored particles having a specific bulk density and particle size as an essential component I came up with a method of roller coating the material and completed the present invention.

That is, the present invention has the following features.
1. A film forming method in which at least an intermediate coating material is applied to a wall surface, and then a top coating material is roller-coated,
As the topcoat material, a synthetic resin emulsion (m) and a lightweight colored particle (n) having a bulk density of 1.0 g / ml or less and an average particle diameter of 0.01 to 1 mm are essential components, and the synthetic resin emulsion ( Using a topcoat material containing 0.1 to 50 parts by weight of the lightweight colored particles (n) per 100 parts by weight of the solid content of m),
A method of forming a coating, wherein the coating of the intermediate coating material and the coating of the top coating material have different degrees of gloss.
2. 1. The lightweight colored particles (n) are granular. The described coating method.
3. 1. A fibrous roller having a hair length of 10 mm or more is used as the roller. or 2. The film forming method according to .

According to the present invention, a uniform spotted pattern can be reliably formed on an existing wall surface at a construction site or the like by roller coating, and a highly aesthetic finish can be easily obtained.

It is a figure which shows an example of a roller.

EMBODIMENT OF THE INVENTION Hereinafter, the form for implementing this invention is demonstrated.

The surface to be coated in the present invention is an existing wall surface that exists as a building, a civil engineering structure, or the like. Examples of the base material that constitutes the wall surface include concrete, mortar, cement board, extruded board, slate board, PC board, ALC board, fiber reinforced cement board, metal siding board, ceramic siding board, ceramic board, and silicic acid. Calcium board, gypsum board, plastic board, hardwood cement board, PVC extruded siding board, plywood, etc., or those having a coating film on the surface thereof. The present invention is particularly preferably applicable to existing wall surfaces made of inorganic building materials such as siding boards and ALC boards. When the wall surface is composed of a plurality of inorganic building materials, the joints between the inorganic building materials may be filled with a joint material such as a sealing material or a dry joint material.

In the present invention, the wall surface as described above can be coated with an undercoat material, if necessary, an intermediate coat material, and then a topcoat material.

Of these, as the undercoat material, those having at least one or more functions selected from, for example, adhesion, water permeation resistance, substrate reinforcement, concealability, base adjustment, and base conformability can be used. Examples of such undercoat materials include fillers, surfacers, sealers, primers, and the like. In the present invention, one or two or more undercoat materials can be used as necessary.

As the intermediate coating material, for example, a material having coloring properties and the like can be used. By using such an intermediate coating material, a desired color can be imparted to the surface to be coated before the top coating material is applied. The intermediate coating material may further have at least one or more functions selected from, for example, weather resistance, durability, heat shielding, hiding properties, and waterproofing. If the intermediate coating material has sufficient performance such as adhesion to the surface to be coated, the coating of the undercoat material is not essential.

As the intermediate coating material, for example, one containing a binder and a color pigment can be used. Examples of binders include acrylic resins, urethane resins, epoxy resins, vinyl acetate resins, silicone resins, fluorine resins, acrylic vinyl acetate resins, acrylic urethane resins, acrylic silicone resins, and various resins such as composite resins thereof. mentioned. These can be used singly or in combination of two or more. As such a binder, for example, a water-dispersible resin (resin emulsion), a water-based resin such as a water-soluble resin can be preferably used. The glass transition temperature of the binder (value obtained from the FOX formula) is preferably 60°C or less, more preferably -50 to 50°C. In the present invention, "α to β" has the same meaning as "more than or equal to α and less than or equal to β".

Examples of coloring pigments include titanium oxide, zinc oxide, alumina, carbon black, graphite, black iron oxide, iron-manganese composite oxide, iron-copper-manganese composite oxide, iron-chromium-cobalt composite oxide, copper -chromium composite oxide, copper-manganese-chromium composite oxide, ferric oxide, molybdate orange, permanent red, permanent carmine, anthraquinone red, perylene red, quinacridone red, yellow iron oxide, titanium yellow, Fast yellow, benzimidazolone yellow, chrome green, cobalt green, phthalocyanine green, ultramarine blue, Prussian blue, cobalt blue, phthalocyanine blue, quinacridone violet, dioxazine violet, aluminum pigment, pearl pigment and the like. These can be used singly or in combination of two or more. By appropriately using one or more of these color pigments, the color tone of the intermediate coating material film can be adjusted. The average particle size of the color pigment is preferably 2 μm or less, more preferably 0.01 to 1 μm. The average particle size of the color pigment is an average value measured using a laser diffraction particle size distribution analyzer (measurement temperature: 25°C).

In addition to the above components, the intermediate coating material includes, for example, extender pigments, dyes, aggregates, color grains, matting agents, thickeners, wetting agents, leveling agents, antifreezing agents, film forming aids, preservatives, Anti-mildew agent, anti-algae agent, antibacterial agent, dispersant, surfactant, antifoaming agent, UV absorber, light stabilizer, antioxidant, adhesion imparting agent, anti-staining agent, hydrophilizing agent, water repellent agents, cross-linking agents, curing agents, curing accelerators, plasticizers, coupling agents, adsorbents, pH adjusters, catalysts, water, solvents and the like. The intermediate coating material can be produced by uniformly mixing such components by a conventional method.

The pigment volume concentration (PVC) of the intermediate coating material is preferably 50% or less, more preferably 30% or less, still more preferably 3 to 25%, and particularly preferably 5 to 20%. The use of such an intermediate coating material is advantageous in terms of substrate conformability (such as conformability to walls with joints filled with sealant, etc.) and the ability to finish using the texture of the surface to be coated. acts on Furthermore, it is also possible to set the glossiness of the intermediate coating material to be high. The pigment volume concentration is the volume percentage of the pigment contained in the dry film, and is a value obtained by calculation from the mixed amount of the resin and the pigment that constitute the intermediate coating material. The specific gravity of the resin is assumed to be 1.

A known method can be adopted for coating the intermediate coating material. Examples of coating methods include spray coating, roller coating, and brush coating. For roller coating, a fibrous roller can be preferably used. The coating amount of the intermediate coating material is preferably 0.05-0.8 kg/m ² , more preferably 0.1-0.6 kg/m ² . At the time of coating, a diluent such as water can be mixed to appropriately adjust the viscosity. Drying of the intermediate coating material is preferably carried out at room temperature (0 to 40° C.). When the intermediate coating material is applied, the top coating material can be applied after the intermediate coating material is dried.

In the painting of the intermediate coating material, the entire wall surface can be coated with one type (one color) of intermediate coating material, or two or more types of intermediate coating materials with different color tones can be used for coating. In the latter case, for example, after the first intermediate coating material is applied to the entire surface to be coated, a second intermediate coating material (different color from the first intermediate coating material) is partially coated, or the first intermediate coating material and the second intermediate coating material are applied. A multicolor pattern in which two or more colors are mixed can be formed by a method of separately applying the intermediate coating material to each predetermined region. In the present invention, by applying such an intermediate coating material, it is possible to finish the surface to be coated while making the most of the texture of the surface to be coated while imparting the desired color to the surface to be coated.

Examples of the intermediate coating material include forms such as glossy and matte (including 70% gloss, 50% gloss, 30% gloss, etc.). Such an intermediate coating material coating is selected according to the relationship with the glossiness of the top coating material coating, which will be described later. The matte intermediate coating material film can be formed of an intermediate coating material containing a matting agent such as an extender pigment, for example, in the same manner as the overcoat material described later.

In the present invention, the topcoat material is roller-coated on the wall surface as described above. The topcoat material in the present invention contains a synthetic resin emulsion (m) and specific lightweight colored particles (n) as essential components. In the present invention, it is possible to form a uniform spotted pattern by roller-coating such a specific topcoat material. The final finished appearance is the background color (the color of the surface to be coated before the topcoat material is applied. If the intermediate coating material is applied, the color of the intermediate coating material film.) with a speckled pattern of lightweight colored particles (n). It becomes a thing that has been made, and excellent designability is expressed.

Among the components constituting the topcoat material, the synthetic resin emulsion (m) (hereinafter also referred to as "(m) component") acts as a binder. As the component (m), those that form a transparent film can be used. Specific examples of component (m) include vinyl acetate resin emulsions, epoxy resin emulsions, acrylic resin emulsions, urethane resin emulsions, acrylic silicone resin emulsions, fluororesin emulsions, and composite resin emulsions thereof. can. Among these, acrylic resin emulsions, urethane resin emulsions, acrylic silicon resin emulsions, fluororesin emulsions, and composite resin emulsions thereof are preferable from the viewpoint of weather resistance. These (m) components can be used singly or in combination of two or more, and two or more (m) components can be mixed. The component (m) may have cross-linking reactivity.

Component (m) can be produced, for example, by a single-stage or multi-stage (two-stage, or three-stage or more) emulsion polymerization method. Among them, when multi-stage emulsion polymerization is employed, for example, a multi-layer structure emulsion (core-shell emulsion, etc.) can be obtained.

The average particle size of component (m) is preferably 30 to 500 nm, more preferably 50 to 300 nm. When the topcoat material contains such an average particle size (m) component, the topcoat material to be applied to painting tends to have a milky appearance, and the topcoat material coating immediately after painting (before drying) also exhibits a milky white color. It acts favorably for suppressing uncoated areas. The average particle size of component (m) can be measured using a dynamic light scattering measurement device (measurement temperature: 25°C). The glass transition temperature of the resin constituting component (m) is preferably -30 to 80°C, more preferably -20 to 60°C. The glass transition temperature can be determined by the Fox formula.

As the lightweight colored particles (n) (hereinafter also referred to as “component (n)”) in the overcoat material, those having a bulk density of 1.0 g/ml or less and an average particle size of 0.01 to 1 mm are used. As the component (n), one or two or more kinds of lightweight colored particles satisfying such conditions can be used.

The bulk density of component (n) is 1.0 g/ml or less, preferably 0.01 to 0.95 g/ml, more preferably 0.1 to 0.9 g/ml, still more preferably 0.2 to 0.9 g/ml. 8 g/ml. When the bulk density of the component (n) is within the above range, it is possible to form a uniform spotted pattern, which is preferable in terms of coating workability and the like. If the bulk density of the component (n) exceeds the above upper limit, the particles tend to gather together on the surface to be coated during roller coating, and the spotted pattern may be uneven. The bulk density in the present invention is a value measured by supplying lightweight colored particles to a cylindrical container and applying vertical vibration (tapping vibration) until the bulk of the lightweight colored particles in the container changes completely.

The average particle size of component (n) is 0.01 to 1 mm, preferably 0.02 to 0.5 mm, more preferably 0.03 to 0.3 mm. When the average particle size of the component (n) is within the above range, it is possible to form a uniform spotted pattern, which is also preferable in terms of coating workability and the like. If the average particle size of the component (n) is smaller than the above lower limit, the speckled pattern will be difficult to recognize on the finished surface after coating. If the average particle size of the component (n) is larger than the above upper limit, clustering of particles and convexity of particles become conspicuous, which is disadvantageous in terms of finish and appearance. Moreover, there is also a possibility that coating workability may deteriorate.

Although the shape of component (n) is not particularly limited, it is preferably in the form of granules in the present invention. The term "granular" as used herein means a shape in which the average particle size and average thickness are approximate values. Specifically, the (n) component preferably has a ratio of average particle size to average thickness (average particle size/average thickness) of 2 or less (preferably 1.5 or less). The use of such a shape is more preferable in terms of homogenization of the spotted pattern, and can improve the aesthetic appearance of the formed film.

The average particle diameter of the component (n) is the average value of the major diameters of particles placed on a horizontal surface in the most stable posture and observed from above. The average thickness is the average value of interplanar distances when particles placed on horizontal surfaces in the most stable posture are sandwiched between horizontal surfaces.

As the (n) component in the topcoat material, it is desirable to include a color different from the background color before coating the topcoat material. As a result, the speckled pattern due to the component (n) can be sufficiently visually recognized on the finished surface after coating. When two or more types of intermediate coating materials are applied separately before coating with the top coating material, the color tone of the component (n) may be different from that of at least one type of intermediate coating material.

In the present invention, the term "different color" refers to a color tone that can be visually recognized as a different color. The color difference (ΔE) is preferably 5 or more, more preferably 10 or more, still more preferably 20 or more. The color difference (ΔE) is a value calculated based on the L ^* value, a ^* value, and b ^* value measured using a color difference meter. For particles such as component (n), particles are placed on a glass plate until the glass surface is covered, and the surface covered with a PE film (colorless and transparent) is measured.

As the component (n), for example, rubber, resin, mineral, wood, plant-based materials can be used, and organic particles based on rubber or resin are particularly preferable. The internal structure of component (n) is not particularly limited as long as the bulk specific gravity, average particle size, etc. satisfy the above conditions, and examples thereof include solid bodies, foamed bodies, porous bodies, and the like. The color tone of the component (n) may be, for example, one that makes use of the original color tone of the base material, or the base material is subjected to coloring treatment (for example, coloring treatment of the inside of the base material, coloring coating of the surface of the base material, etc.). It can also be given by

The amount of component (n) mixed is 0.1 to 50 parts by weight, preferably 0.5 to 30 parts by weight, more preferably 1 to 20 parts by weight, per 100 parts by weight of the solid content of component (m). is. By setting the amount of the component (n) to be mixed within such a range, it is possible to form a highly aesthetically pleasing homogeneous speckled pattern in which the background color is speckled. If the mixing amount of component (n) exceeds the above upper limit, the spotted pattern tends to be uneven, and the background color of the lower layer tends to be hidden, which is disadvantageous in terms of spotted pattern formation. If the amount of component (n) mixed is less than the above lower limit, the speckled pattern will be difficult to recognize on the finished surface after coating.

The overcoat material may contain at least one type (one color) of lightweight colored particles, and may contain two or more types of lightweight colored particles having different color tones.

The topcoat material is, for example, a coloring pigment, an extender pigment, a dye, a matting agent, a thickener, a wetting agent, a leveling agent, an antifreezing agent, a film-forming aid, and an antiseptic within a range that does not impair the effects of the present invention. , anti-mildew agent, anti-algae agent, antibacterial agent, dispersant, surfactant, defoaming agent, UV absorber, light stabilizer, antioxidant, adhesion imparting agent, anti-staining agent, hydrophilizing agent, repellent A liquid agent, a cross-linking agent, a curing agent, a curing accelerator, a plasticizer, a coupling agent, an adsorbent, a pH adjuster, a catalyst, water, a solvent, and the like may be included. The overcoat material can be produced by uniformly mixing such components by a conventional method.

The heat residue of the overcoating material is preferably 10 to 80% by weight, more preferably 20 to 60% by weight, still more preferably 30 to 55% by weight. The heating residue can be measured according to the method of JIS K5601-1-2 “heating residue” (heating temperature 135° C., heating time 60 minutes).

The formed film of the topcoat material has the component (n) scattered in the transparent film, and exhibits a spotted pattern. That is, it has transparency that allows the background color to be visually recognized before the topcoat material is applied. The transparent film formed by the overcoat material may be either colorless and transparent or colored and transparent. Of these, the colored transparent film can be formed, for example, from a topcoat material containing coloring pigments, dyes, and the like, and the degree of coloring may be set within a range in which the background color and spotted pattern can be visually recognized.

Formation coatings of the topcoat material (topcoat material coating) include, for example, glossy, matte (including 7 minutes gloss, 5 minutes gloss, 3 minutes gloss, etc.) and the like. Such a topcoat material coating is selected according to the relationship with the glossiness of the intermediate coating material coating. Among them, the matte topcoat material film can be formed, for example, by a topcoat material containing a matting agent such as an extender. Moreover, it is also possible to obtain a matte topcoat material film by using a topcoat material in which two or more kinds of resins are combined. When the overcoat material contains a matting agent, the glossiness can be set by adjusting the type and ratio of the matting agent.

Examples of matting agents that can be used include extender pigments, and specific examples include heavy calcium carbonate, light calcium carbonate, clay, kaolin, talc, barium carbonate, white carbon, diatomaceous earth, cold water stone, china clay, and china. Clay, barite powder, barium sulfate, precipitated barium sulfate, silica sand, silica stone powder, quartz powder, resin powder, resin beads, glass beads, hollow balloons, zeolite, sodium sulfate, alumina, allophane, vermiculite, perlite, Oya stone powder, activity White clay, shirasu balloon and the like can be mentioned. These can be used singly or in combination of two or more. As the extender pigment, a non-colored product that has not undergone a coloring treatment can be used. In particular, it is preferable to use extender pigments having a refractive index of 1.4 to 1.7. By using such an extender pigment, it is possible to enhance the matting effect while maintaining the transparency of the film. The refractive index can be measured using an Abbe refractometer. The average particle size of the extender pigment is preferably 100 μm or less, more preferably 1 to 60 μm, still more preferably 2 to 40 μm, from the viewpoints of transparency, texture and matting effect of the coating. The average particle size of the extender is an average value measured using a laser diffraction particle size distribution analyzer (measurement temperature: 25°C).

When the topcoat material contains an extender, the amount of the extender mixed depends on the degree of matting, but is preferably 10 to 200 parts by weight with respect to 100 parts by weight of the solid content of the component (m). 20 to 120 parts by weight.

The topcoat material of the present invention is different from materials called multicolored pattern paint (multicolor paint), stone finish topcoat material (stone tone paint), and the like. In general, multicolored pattern paints contain a high proportion of liquid or gel-like colored particles, and these colored particles form multicolored patterns. It contains a high proportion of aggregate, and expresses a stone-like texture due to the coloring of these aggregates. On the other hand, the topcoat material of the present invention forms a speckled pattern in which the lightweight colored particles (n) are scattered due to the structure described above. The main color is represented by the background color.

In the present invention, the intermediate coating material film and the top coating material film are different in glossiness. That is, as the intermediate coating material and the top coating material, materials having coatings with different glossiness are used. In the present invention, by using the intermediate coating material and the top coating material that satisfy these conditions, even if there is an uncoated area of the top coating material, it is possible to identify the area without difficulty and repair the area. is also easier to do. The glossiness difference between the intermediate coating material coating and the top coating coating is preferably 5 or more, more preferably 15 or more, still more preferably 30 or more, particularly preferably 45 or more, and most preferably 60 or more.

The glossiness in the present invention is a value measured according to JIS K5600-4-7 "specular glossiness". Specifically, the sample was applied to a flat substrate (a transparent glass plate for the intermediate coating material and a black acrylic plate for the top coating material) using a film applicator with a gap of 150 μm, and the standard conditions (temperature 23 ° C., relative It is the average value of the 60-degree specular gloss measured using a gloss meter after drying for 48 hours under a humidity of 50%.

As a combination of such an intermediate coating material and a topcoat material, for example, the intermediate coating material coating has a low glossiness and the topcoat material coating has a high glossiness (the topcoat material coating has a higher glossiness than the intermediate coating material coating). In the case, when the intermediate coating material coating has a high glossiness and the top coating material coating has a low glossiness (the glossiness of the top coating material coating is lower than that of the intermediate coating material coating). Of these, the latter case is preferable in that a high-quality and aesthetically pleasing finish can be obtained, and in that the ability to conform to the base is enhanced. In the latter case, for example, the intermediate coating material coating may be in the form of a glossy coating, and the top coating material coating may be in the form of a matte coating.

When two or more kinds of intermediate coating materials are used for separate coating, it is desirable that the intermediate coating material coating and the top coating coating material satisfy the above conditions.

In the present invention, the topcoat material is applied using a roller. In the present invention, by such roller coating, it is possible to suppress the scattering of the topcoat material and improve the adhesion of the topcoat material to the surface to be coated. As the roller, for example, a fibrous roller, a porous roller, or the like can be used. Of these, fibrous rollers are preferred in the present invention.

In the present invention, it is desirable to roll coat the overcoat material using a fibrous roller having a hair length of 10 mm or more. This makes it possible to form a more uniform spotted pattern. It is considered that such an effect is exhibited by the long fibers of the fibrous roller sufficiently promoting the dispersion of these lightweight colored particles (n) during roller coating.

An example of such a roller is shown in FIG. The roller in FIG. 1 is a fibrous roller, and has a fibrous layer on the outer surface of a tubular core. The cylindrical core member is hollow so that a handle with a shaft can be attached, and the hollow can be used with the handle attached. As the cylindrical core material, for example, a core material made of plastic, wood, metal, paper, or the like can be used. A mounting aid or the like can be provided between the shaft and the core material. The outer diameter of the fibrous roller is preferably between 30 and 80 mm. The length of the fibrous roller is preferably 50-300 mm.

The length of the fibrous roller is preferably 10 mm or more, more preferably 12 mm or more, still more preferably 15-40 mm, particularly preferably 18-38 mm, and most preferably 20-36 mm. The hair length is the length of the fibers that constitute the fibrous roller. Specifically, the hair length is obtained by lightly pinching the fibers of the dry fibrous roller with fingers, measuring the length of the fibers when they are stretched outward from the core material, and calculating the average value. be able to. A fibrous roller having such bristles is more advantageous in forming a uniform spotted pattern.

Examples of the material of the fiber constituting the fibrous layer include pig hair, horse hair, goat hair, wool, raccoon hair, human hair, silk, cotton, etc., or acrylic fiber, polyurethane fiber, polyester fiber, polypropylene fiber, etc. and synthetic fibers. The fibrous layer can be formed by weaving or weaving such a fiber assembly (for example, cotton-like pile, thread-like pile, etc.).

When applying the topcoat material using such a fibrous roller, the viscosity of the topcoat material can be appropriately set. The topcoat material to be applied for coating can be diluted with water or the like as necessary. The viscosity of the topcoat material (at the time of coating) is preferably 0.1 to 15 Pa·s, more preferably 0.3 to 13 Pa·s. The thixotropic index (at the time of coating) of the topcoat material is preferably 6 or less, more preferably 1-5. The viscosity is a value determined by measuring the viscosity at 20 rpm with a BH viscometer (guideline value for the fourth rotation). The thixotropy index (TI) is a value determined by the following formula using a BH type viscometer. The measured temperature is 23°C in all cases.
<Formula> TI = η1/η2
(In the formula, η1 is the viscosity at 2 rpm (Pa s: the guideline value for the second rotation), η2 is the viscosity at 20 rpm (Pa s: the guideline value for the 4th rotation))

The topcoat material in the present invention can be applied to the entire wall surface. The coating amount of the topcoat material is preferably 50 g/m ² or more, more preferably 100 to 500 g/m ² , still more preferably 105 to 400 g/m ² . The number of times the topcoat material is applied is preferably 1 to 2 times, more preferably 1 time. By applying the topcoat material under such conditions, a relatively thick film is formed, and the light colored particles (n) are more likely to disperse, which is further advantageous in forming a uniform spotted pattern.

Drying after coating the topcoat material is preferably carried out at room temperature (0 to 40° C.). The drying time is preferably 1 hour or more, preferably about 2 to 24 hours.

In the present invention, the presence or absence of uncoated topcoat material can be easily determined by visually confirming the appearance after drying the topcoat material. If an unpainted area occurs, the area can be repaired. In the repair, the topcoat material from the previous step may be used to apply the topcoat material to the uncoated area. For repairing, for example, a brush, a roller, or the like can be used. As the roller, a fibrous roller similar to that described above can be used.

In the present invention, it is possible to improve the appearance of the existing wall surface at a construction site or the like by the film forming method as described above. The present invention is suitable for repairing (renovating) such wall surfaces. By applying the film forming method of the present invention to a wall surface that has deteriorated over time, it is possible to improve the aesthetic appearance of the wall surface, and it is possible to restore the color of the new building. Coloring is also possible. For wall surfaces composed of inorganic building materials such as siding boards and ALC plates, and having joints filled with a sealant or the like in the joints of the inorganic building materials, the entire surface including the inorganic building materials and the joints is subjected to the method of the present invention. can also be applied.

Examples and comparative examples are shown below to further clarify the features of the present invention. It should be noted that the invention is not limited to the examples herein.

As topcoat materials, the following materials were prepared.
・ Topcoat material 1
Synthetic resin emulsion a (acrylic silicone resin emulsion, solid content 50% by weight, glass transition temperature 32 ° C., average particle diameter 110 nm) is added to 200 parts by weight of lightweight colored particles a (black resin particles, bulk density 0.68 g / ml, 4 parts by weight of film-forming aid, matting agent a (non-colored resin particles, refractive index of 1.5, average particle diameter 15 μm), 1 part by weight of an ultraviolet absorber, 2 parts by weight of a viscosity modifier, 3 parts by weight of an antifoaming agent, and water to prepare a heating residue of 40% by weight. Thus, topcoat material 1 was obtained. The 60-degree specular glossiness of this topcoat material 1 was 3.

・ Topcoat material 2
Synthetic resin emulsion b (acrylic resin emulsion, solid content 50% by weight, glass transition temperature 34 ° C., average particle diameter 150 nm) 200 parts by weight, lightweight colored particles b (black resin particles, bulk density 0.68 g / ml, average Particle diameter 0.08 mm, average particle diameter / average thickness = 1.0) 8 parts by weight, film-forming aid 12 parts by weight, matting agent b (uncolored resin particles, refractive index 1.5, average particle diameter 8 μm), 2 parts by weight of a viscosity modifier, 3 parts by weight of an antifoaming agent, and water to prepare a heating residue of 45% by weight. The 60-degree specular glossiness of this topcoat material 2 was 2.

・ Topcoat material 3
Synthetic resin emulsion c (acrylic silicone resin emulsion, solid content 50% by weight, glass transition temperature 38 ° C., average particle diameter 100 nm) is added to 200 parts by weight of lightweight colored particles c (black resin particles, bulk density 0.69 g / ml, 2 parts by weight of film-forming aid, 47 parts by weight of matting agent a (same as above), 1 part by weight of ultraviolet absorber 2 parts by weight of a viscosity modifier, 3 parts by weight of an antifoaming agent, and further mixed with water to prepare a heating residue of 42% by weight, thereby obtaining a topcoat material 3. The 60-degree specular glossiness of this overcoating material 3 was 4.

・ Topcoat material 4
A topcoat material 4 was obtained in the same manner as the topcoat material 1 except that the amount of the lightweight colored particles a mixed was 12 parts by weight. The 60-degree specular glossiness of this overcoating material 4 was 3.

・ Topcoat material 5
A topcoat material 5 was obtained in the same manner as the topcoat material 1 except that the amount of the lightweight colored particles a mixed was 32 parts by weight. The 60-degree specular glossiness of this overcoating material 5 was 3.

・ Top coat material 6
With respect to 200 parts by weight of synthetic resin emulsion a (same as above), 4 parts by weight of lightweight colored particles a (same as above), 12 parts by weight of film-forming aid, 1 part by weight of ultraviolet absorber, 2 parts by weight of viscosity modifier, A topcoat material 6 was obtained by mixing 3 parts by weight of an antifoaming agent and further mixing water to prepare a heating residue of 40% by weight. The 60-degree specular glossiness of this overcoating material 6 was 85.

・ Top coat material 7
In the topcoat material 6, instead of the lightweight colored particles a, 4 parts by weight of black silica sand (bulk density 1.2 g / ml, average particle diameter 0.12 mm, average particle diameter / average thickness = 1.2) was mixed. obtained topcoat material 7 in the same manner as topcoat material 6. The 60-degree specular glossiness of this overcoating material 7 was 85.

・ Top coat material 8
In the topcoat material 6, instead of the lightweight colored particles a, 4 parts by weight of black mica (bulk density 0.40 g / ml, average particle diameter 0.12 mm, average particle diameter / average thickness = 28) was mixed. Topcoat material 8 was obtained in the same manner as topcoat material 6 . The 60-degree specular glossiness of this overcoating material 8 was 85.

As the intermediate coating material, the following materials were prepared.
・ Intermediate coating material 1 (light gray acrylic resin emulsion paint, pigment volume concentration 13%, 60 degree mirror glossiness 85)
・ Middle coating material 2 (light gray acrylic resin emulsion paint, pigment volume concentration 16%, 60 degree mirror glossiness 50)
・ Intermediate coating material 3 (light gray acrylic resin emulsion paint, pigment volume concentration 19%, 60 degree mirror glossiness 32)

The following rollers were prepared.
・Roller 1 (fiber roller (wool roller), hair length 25 mm)
・Roller 2 (fiber roller (wool roller), hair length 32 mm)
・Roller 3 (fiber roller (wool roller), hair length 21 mm)
・Roller 4 (fiber roller (wool roller), hair length 13 mm)

(Example 1)
A ceramic siding board with a brick-like uneven pattern is spray-painted with a coating amount of 100 g / m ² of undercoat material a (water-based epoxy sealer) over the entire surface, dried for 3 hours, and then coated with intermediate coating material 1. The entire surface was spray-coated at 150 g/m ² and dried for 2 hours. After that, intermediate coating material 1 was again spray-coated over the entire surface at a coating amount of 150 g/m ² and dried for 24 hours. A masking seal having a diameter of 8 mm was attached to the surface of the intermediate coating material, one per 10 cm ³ . Next, topcoat material 1 was applied to the entire surface with a coating amount of 150 g/m ² using roller 1, dried for 24 hours, and then the masking seal was removed. All of the above steps were performed under standard conditions (temperature of 23° C., relative humidity of 50%). The color difference between the black resin particles and the intermediate coating material 1 was 52.

The specimens obtained by the above method were visually evaluated for uncoated discrimination and finish. The evaluation criteria for unpainted discriminability (denoted as “distinguishability” in the table) are “A” when the masking part can be easily discriminated, and “D” when the masking part is difficult to discriminate. It was evaluated in stages (excellent: A>B>C>D: inferior). The evaluation criteria for the finished quality are "A" when a uniform spotted pattern is formed by the colored particles, and "D" when the uneven spotted pattern is conspicuous due to gathering of the colored particles. It was evaluated in four stages (excellent: A>B>C>D: inferior). Table 1 shows the results.

(Examples 2 to 11, Comparative Examples 1 to 3)
Intermediate coating material 1, roller 1, except for using the intermediate coating material, roller, and top coating material listed in Table 1 instead of the top coating material 1. A test specimen was prepared in the same manner as in Example 1, and uncoated discrimination was performed. The properties and finish were evaluated. Table 1 shows the results.

Claims (3)

A film forming method in which at least an intermediate coating material is applied to a wall surface, and then a top coating material is roller-coated,
As the topcoat material, a synthetic resin emulsion (m) and a lightweight colored particle (n) having a bulk density of 1.0 g / ml or less and an average particle diameter of 0.01 to 1 mm are essential components, and the synthetic resin emulsion ( Using a topcoat material containing 0.1 to 50 parts by weight of the lightweight colored particles (n) per 100 parts by weight of the solid content of m),
A method of forming a coating, wherein the coating of the intermediate coating material and the coating of the top coating material have different degrees of gloss. 2. A method according to claim 1, wherein said lightweight colored particles (n) are granular. 3. The method of forming a film according to claim 1, wherein the roller is a fibrous roller having a hair length of 10 mm or more.

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