JP7668861B2 - Coating material and coating formation method - Google Patents

Description

The present invention relates to a novel coating material.

Conventionally, decorative finishing methods that impart the aesthetic quality of natural stone to buildings and civil engineering structures have been known. In recent years, there has been an increasing demand for decorative finishing that incorporates designs that have the texture and depth characteristic of natural stone. For example, Patent Document 1 describes one such method, which involves spraying granular material made of mica and transparent and/or translucent aggregate onto the surface of a base material after the base material has been applied and before the base material dries.

Japanese Patent Application Publication No. 5-50025

However, as in Patent Document 1, in order to impart a natural sense of depth, it is necessary to apply a decorative material such as mica in a separate process, which can complicate the process. Under these circumstances, there is a demand for a coating material and a coating formation method that can easily create a natural stone-like finish with a sense of depth.

As a result of intensive research into solving the above problems, the inventors came up with the idea of easily achieving a finish with excellent aesthetics, such as a sense of depth, by using a coating material containing a resin component and a specific aggregate in a specific weight ratio, and thus completed the present invention. In other words, the present invention has the following characteristics.

That is, the present invention has the following features.
1. A coating material comprising a resin component (A) and an aggregate (B),
The coating material contains 100 to 2,000 parts by weight of aggregate (B) per 100 parts by weight of solid content of resin component (A),
The aggregate (B) includes a scaly colored aggregate (b1), a granular translucent aggregate (b2), and a granular opaque colored aggregate (b3),
the weight ratio (b2)/(b1) of the scaly colored aggregate (b1) to the granular translucent aggregate (b2) is 5/1 to 180/1;
the weight ratio (b3)/(b1) of the scaly colored aggregate (b1) to the granular opaque colored aggregate (b3) is 10/1 to 200/1;
the weight ratio (b3)/(b2) of the granular translucent aggregate (b2) to the granular opaque colored aggregate (b3) is 0.1/1 to 5/1;
The above-mentioned scaly colored aggregate (b1) is obtained by coloring scaly base particles,
The granular translucent aggregate (b2) has a light transmittance of 3% or more and 50% or less,
The coating material is characterized in that the granular opaque colored aggregate (b3) has a light transmittance of less than 3%.
2. The coating material according to 1. , wherein the granular translucent aggregate (b2) includes a granular translucent aggregate (b2') having an average particle size of 1 μm or more and less than 150 μm.
3. A method for forming a coating, comprising applying the coating material according to any one of 1. to 2. onto a substrate to form a coating.

The present invention can impart design features such as a sense of depth and enhance the aesthetic appearance.

The following describes how to implement the present invention.

<Coating material>
The coating material of the present invention is characterized by containing a resin component (A) and a specific aggregate (B) in a specific weight ratio.

The resin component (A) (hereinafter referred to as "component (A)") is not particularly limited, but is preferably one or more selected from water-soluble resins and water-dispersible resins. Examples of the resin include vinyl acetate resin, polyester resin, alkyd resin, vinyl chloride resin, epoxy resin, acrylic resin, urethane resin, acrylic silicone resin, fluororesin, etc., or composites thereof. These can be used alone or in combination of two or more. In addition, these components (A) may have crosslinking reactivity. When a component (A) having crosslinking reactivity is used, the water resistance, weather resistance, chemical resistance, etc. of the coating can be improved.

The aggregate (B) (hereinafter referred to as "component (B)") contributes to excellent design. There are no particular limitations on the aggregate as long as it is a solid particle having some color effect, and it can be either inorganic or organic, and can be either natural or artificial. Specific examples include ground calcium carbonate, kansui stone, mica, kaolin, clay, china clay, china clay, talc, aluminum hydroxide, magnesium hydroxide, shells, barite powder, marble, granite, serpentine, granite, fluorite, feldspar, silica stone, silica sand, etc., ground ceramics, ground ceramics, glass beads, ground glass, inorganic particles such as metal pieces and metal powder, and organic particles such as resin beads, ground resins, rubbers, plastics, plant fibers, and plant pieces. Colored aggregates can also be used. By using one or more of these in combination, various natural stone-like colors can be expressed.

Component (B) is mixed in a ratio of 100 to 2000 parts by weight (preferably 150 to 1500 parts by weight, more preferably 200 to 1000 parts by weight) per 100 parts by weight of the solid content of component (A). Mixing component (B) in such a ratio makes it easier to form a thick coating, enhances the sense of weight of the formed coating, and also makes it possible to form a coating that has water vapor permeability. In the present invention, "α to β" is synonymous with "α or more and β or less."

The present invention is characterized in that the above component (B) contains a specific ratio of scaly colored aggregate (b1), granular translucent aggregate (b2), and granular colored aggregate (b3). This gives the concrete a sense of depth, luxury, and solidity, and enhances its aesthetic appearance.

The scaly colored aggregate (b1) (hereinafter referred to as "(b1) component") provides an accent design to the formed coating, enhancing its design. The size of the (b1) component is preferably a long diameter of 0.5 mm or more (more preferably 1 mm or more), and the ratio of the short diameter to the long diameter (short diameter/long diameter) is 0.3 to 1. When the size of the (b1) component satisfies the above range, its shape is easily visible, making it suitable as an accent design. Note that the long diameter and short diameter of the (b1) component are measured by placing the (b1) component stably on a horizontal surface and observing it from above using a microscope.

The thickness of component (b1) is preferably 50 to 500 μm (more preferably 60 to 450 μm). In such a case, component (b1) is easily transferred, and even if it is embedded in the coating, it is possible to impart design properties. In the present invention, component (b1) preferably has a ratio of major axis to thickness that satisfies (major axis/thickness)>2 (more preferably 3, and even more preferably 5). The thickness of component (b1) is a value measured with a micrometer.

Examples of such (b1) components include colored flake-like base particles. Specific examples of base particles include inorganic pieces such as mica, sericite, clay, talc, plate-like kaolin, barium sulfate flakes, glass flakes, alumina flakes, shell pieces, and metal pieces, as well as rubber pieces, plastic pieces, and wood pieces. There are no particular limitations on the coloring treatment, but a method in which a colorant containing a pigment is coated on the surface of the base particles is preferred. One or more types of (b1) components (one color or two or more colors) can be used in combination to produce a variety of colors.

The granular translucent aggregate (b2) (hereinafter referred to as "component (b2)") imparts transparency to the formed coating and enhances the design, such as the sense of depth. In particular, in the present invention, the accent design of component (b1) can be seen through component (b2), which further enhances the sense of depth and is preferable in terms of improving aesthetics.

The (b2) component preferably has a light transmittance of 3% or more (more preferably 3% to 50%, and even more preferably 10% to 30%). In such a case, the above-mentioned effects can be sufficiently obtained.
The light transmittance is the total light transmittance measured by a turbidimeter. In this measurement, a sample of component (b2) is filled into a transparent glass cell having an inner thickness of 5 mm, and then water is gradually added thereto. After that, air bubbles in the cell are removed by vibration.

Examples of such (b2) components include silica, calcium carbonate, sappanite, feldspar, quartz, etc., as well as crushed products thereof, crushed glass, glass beads, etc., and either colorless or colored types can be used as long as they satisfy the above-mentioned light transmittance. These can be used alone or in combination of two or more types. Among these, in the present invention, it is particularly preferable to include one type selected from calcium carbonate and sappanite.

The average particle size of component (b2) is preferably 1 μm or more and 1 mm or less (more preferably 2 μm or more and 800 μm or less, and even more preferably 3 μm or more and 600 μm or less). If this range is satisfied, the sense of depth of the formed coating can be enhanced.

The (b2) component is characterized in that the weight ratio (b2)/(b1) to the (b1) component is 5/1 to 180/1 (more preferably 8/1 to 150/1, and even more preferably 10/1 to 100/1). When this range is satisfied, the accent design of the (b1) component can be seen through the (b2) component, which gives a sense of depth and further enhances the aesthetic appeal.

Furthermore, in the present invention, it is preferable that the (b2) component contains granular translucent aggregate (b2') having an average particle size of 1 μm or more and less than 150 μm (more preferably 2 μm or more and 100 μm or less, and even more preferably 3 μm or more and 80 μm or less). This makes the accent design of the formed coating more visible, and enhances the sense of depth. Such (b2') component is preferably 10 to 60% by weight (more preferably 15 to 55% by weight, even more preferably 20 to 50% by weight, and particularly preferably 25 to 45% by weight) in the (b2) component. In such a case, a portion where the (b2') is overlapped on the (b1) component is easily formed near the surface of the coating, which can impart a sense of depth to the accent design, thereby further enhancing the above effect. The average particle size of component (b2) is the average value measured using a laser diffraction particle size distribution analyzer (measurement conditions: distribution standard: volume, refractive index: 1.60-0.10i).

The granular colored aggregate (b3) (hereinafter referred to as "component (b3)") is an opaque granular particle that mainly imparts color to the formed coating. As such component (b3), an opaque one having a light transmittance of less than 3% is preferable, and one having a light transmittance of 2% or less is more preferable.
The light transmittance is the total light transmittance measured by a turbidimeter. In this measurement, a sample of component (b3) is filled into a transparent glass cell having an inner thickness of 5 mm, and then water is gradually added thereto. After that, air bubbles in the cell are removed by vibration.

The (b3) component may be any opaque material, such as marble, granite, serpentine, granite, fluorite, sapphire, feldspar, silica, silica sand, and crushed products thereof, crushed porcelain, crushed ceramic, crushed glass, glass beads, crushed resin, resin beads, metal particles, and the like, as well as those with colored surface coatings. By using one or a combination of two or more of these, it is possible to express a variety of natural stone-like colors.

The average particle size of the (b3) component is preferably 5 μm or more and 1 mm or less (more preferably 8 μm or more and 800 μm or less, and even more preferably 10 μm or more and 600 μm or less). The average particle size of the (b3) component is a value obtained by sieving the material using a metal mesh sieve specified in JIS Z8801-1:2000 and calculating the average weight distribution. Such a (b3) component is recognized as granular and is different from the scaly colored aggregate (b1).

In the present invention, it is preferable that the weight ratio (b3)/(b1) of the (b3) component to the (b1) component is 10/1 to 200/1 (more preferably 12/1 to 150/1, and even more preferably 15/1 to 100/1). When this range is satisfied, the accent design is easily visible in the formed coating, and the aesthetics can be further improved.

Furthermore, in the present invention, it is preferable that the weight ratio (b3)/(b2) of the above-mentioned (b3) component to the above-mentioned (b2) component is 0.1/1 to 15/1 (more preferably 0.2/1 to 10/1, and even more preferably 0.3/1 to 5/1). When such a range is satisfied, the desired color can be imparted to the formed coating, and the hiding power of the entire coating can be ensured. In addition, the visibility of the accent design can be improved.

In the present invention, in addition to the above components (b1), (b2), and (b3), the above component (B) may also contain, for example, granular colored aggregate (b4) having an average particle size of more than 1 mm and not more than 10 mm, uncolored scale-like particles (b5), etc., as long as they do not significantly impair the effects of the present invention.

The coating material of the present invention can be manufactured by uniformly mixing the above-mentioned components by a known method, but if necessary, other components that can be used in coating materials can also be mixed in. Examples of such components include color pigments, extender pigments, fibers, film-forming agents, thickeners, leveling agents, plasticizers, antifreeze agents, pH adjusters, preservatives, antifungal agents, anti-algae agents, antibacterial agents, dispersants, defoamers, UV absorbers, light stabilizers, antioxidants, water, etc.

In the present invention, it is preferable that the thickener contains an associative thickener, and among these, a urethane associative thickener containing a hydrophobic group at the end and a urethane bond in the molecular chain is preferable. This improves the transferability of the (b1) component, enhances the design, and improves workability when the coating material is applied to form a patterned coating. The mixing ratio of the thickener is preferably 0.1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight, calculated as solid content, per 100 parts by weight of the solid content of the (A) component.

The viscosity of the coating material when applied (if diluted, the viscosity after dilution) is preferably adjusted to 20 to 200 Pa·s (more preferably 50 to 150 Pa·s), and the thixotropy index is preferably adjusted to 2.0 to 6.0 (more preferably 3.0 to 5.0). In the present invention, by setting the viscosity characteristics of the coating material under such conditions, the transferability of the above-mentioned component (b1) when applied is improved, which is advantageous in terms of improving coating workability and finish.
In the present invention, the viscosity is a value determined by measuring the viscosity at 2 rpm (the indicator value at the second rotation) using a BH type viscometer. The thixotropy index (TI) is a value determined by the following formula using a BH type viscometer. The measurement temperature in both cases is 23°C.
<Formula>TI=η1/η2
(In the formula, η1 is the viscosity at 2 rpm (Pa·s: indicator value at the second rotation); η2 is the viscosity at 20 rpm (Pa·s: indicator value at the fourth rotation))

<Method of forming coating>
The coating material of the present invention is applied to a substrate to form a coating. The substrate constitutes the surface of a building, civil engineering structure, etc. Examples of such substrates include concrete, mortar, siding board, extrusion molding board, gypsum board, perlite board, plywood, brick, plastic board, metal plate, glass, porcelain tile, etc. These substrates may have a coating already formed on their surface, or may have wallpaper attached thereto, etc.

The coating material can be applied with a brush, trowel, roller, spray, etc. to form a coating. In particular, it is preferable to use a roller or trowel in terms of ease of application. In particular, the coating material of the present invention can form a coating with excellent water vapor permeability by forming an uneven coating with a roller.

The roller to be used is not particularly limited, but a porous roller can be suitably used in the present invention. A porous roller is a roller having a porous layer on the outer surface of a cylindrical core material, and the cylindrical core material is hollow so that a handle with a shaft can be attached, and the roller can be used by attaching a handle shaft to the hollow.
The cylindrical core material is not particularly limited, and for example, a core material made of plastic, wood, paper, metal, etc. can be used. In order to increase the adhesion between the handle shaft and the core material, a reinforcing material made of, for example, plastic, rubber, glass, metal, fiber, etc. can be used between the handle shaft and the core material.

The porous roller used in the present invention is preferably one in which 50% or more of the holes on its surface (the outer surface of the porous layer) are 3 mm or more in size (preferably 50% or more of the holes are 3 mm or more and 8 mm or less, more preferably 60% or more of the holes are 3 mm or more and 8 mm or less, and even more preferably 70% or more of the holes are 3 mm or more and 8 mm or less). In the present invention, the size of the holes can be calculated by multiplying the maximum distance from the center of gravity of each hole by 2. The percentage of holes 3 mm or more in size is calculated by (the number of holes 3 mm or more that appear on the surface of the porous layer) / (the total number of holes that appear on the surface of the porous layer) x 100 (%).

Such a porous layer may be a porous layer having interconnected pores or a porous layer having independent pores, but in the present invention, a porous layer having interconnected pores is preferred. There are no particular limitations on the material, but examples include acrylic resin, urethane resin, ester resin, and ethylene resin, and these resins that have been made porous in a sponge-like form are preferred.

The thickness of the porous layer is preferably 3 mm to 50 mm, more preferably 5 mm to 30 mm. At such a thickness, the coating material is applied efficiently and the workability is excellent. The width (length) of the porous roller is not particularly limited, but is preferably about 80 mm to 250 mm, and the diameter (cylinder diameter) of the porous roller (including the porous layer) is preferably about 30 mm to 100 mm.

The amount of the coating material of the present invention to be applied is not particularly limited, but is preferably 0.5 to 6 kg/m ² , and more preferably 1 to 5 kg/m ² . When applied, the coating material of the present invention can be diluted with water. The dilution ratio is preferably 0 to 10% by weight. In such a case, the effect of the present invention can be fully exhibited.

The dry thickness of the coating material (formed coating) of the present invention is preferably 0.1 to 5 mm (more preferably 0.3 to 3 mm). If the formed coating has irregularities, the thickness of the concave and convex parts should be within the above range.

Furthermore, the coating formed by the coating material of the present invention preferably has a water vapor permeability of 5 g/ ^m2 ·24 h or more (more preferably 10 g/ ^m2 ·24 h or more) at a dry film thickness of 0.8 mm. In this range, water vapor due to moisture in the substrate can be sufficiently diffused, and swelling and peeling of the coating can be suppressed. The water vapor permeability in the present invention is measured in accordance with JIS K 5400-1990 8.17 "Water vapor permeability".

The following examples will clarify the features of the present invention.

(Coating materials 1 to 10)
Based on the formulation shown in Table 1, the raw materials were mixed by a standard method, and water was added so that the viscosity (BH type viscometer, 2 rpm) became 80 Pa·s to produce coating materials 1 to 10. The TI values after dilution are also shown in Table 1.

The following components were used:
(A) Acrylic silicone resin emulsion (solid content 50% by weight, medium: water)
(B) Aggregate (b1) Scaly colored particles (black mica pieces, major axis: 1.4-3.8 mm, minor axis: 1.2-3.1 mm, thickness: 0.1-0.4 mm, minor axis/major axis (average value): 0.92, major axis/thickness (average value): 11.4)
(b2) Granular translucent aggregate (kansui stone, average particle size: 200 μm, light transmittance: 16%)
(b2') Granular translucent aggregate (kansui stone, average particle size: 20 μm, light transmittance: 16%)
(b3-1) Granular colored aggregate (a mixture of white silica sand and beige silica sand, average particle size: 180 μm, light transmittance 1% or less)
(b3-2) Granular colored aggregate (mixture of beige silica sand and brown silica sand, average particle size: 350 μm, light transmittance: 1% or less)
・Thickener 1 (urethane association type thickener)
・Thickener 2 (cellulose-based thickener)
・Additives (defoamers, etc.)

(Examples 1 to 7, Comparative Examples 1 to 3)
The coating material was applied to the substrate (slate board) to which the undercoat material had been applied using a porous roller and the coating material at a coating weight of 2 kg/ ^m2 , and the coating material was dried and cured at 23°C for 24 hours to form a patterned coating.
The porous roller used had a diameter (cylinder diameter) of 70 mm, a roller width of 200 mm, a paper core, and a 15 mm thick porous layer made of urethane resin that had been made porous (with interconnected holes) like a sponge, with 82% of the surface of the porous layer being made up of pores measuring 3 mm or more and 8 mm or less.

<Evaluation>
The following evaluations were carried out, and the results are shown in Table 4.
- Sense of depth Excellent sense of depth was rated as "AA" and poor sense of depth was rated as "D", and the ratings were made on a 5-level scale: AA>A>B>C>D.

In Examples 1 to 7, a beautiful natural stone-like coating was formed having an accent design of black mica pieces in a thin beige coating formed from the granular translucent aggregate and the granular colored aggregate.
Furthermore, in Examples 1 to 3, there were areas on the surface of the black mica pieces where the granular translucent aggregate overlapped, and the black mica pieces could be seen through the granular translucent aggregate, forming a coating with an excellent sense of depth. In particular, in Example 1, the sense of depth of the black mica pieces was even more pronounced.
In addition, in Examples 4 and 5, the accent design by the black mica pieces was somewhat strong, while in Examples 6 and 7, the accent design by the black mica pieces was somewhat lacking, resulting in a coating that was somewhat inferior in the sense of depth compared to Examples 1 to 3.
In Comparative Example 1, the accent design was insufficient, and a coating with poor depth was formed. In Comparative Example 2, the accent design by the black mica pieces was somewhat strong, and a coating with poor depth was formed. In Comparative Example 3, there was no accent design, and a coating with poor design was formed.

Claims (3)

A coating material comprising a resin component (A) and an aggregate (B),
The coating material contains 100 to 2,000 parts by weight of aggregate (B) per 100 parts by weight of solid content of resin component (A),
The aggregate (B) includes a scaly colored aggregate (b1), a granular translucent aggregate (b2), and a granular opaque colored aggregate (b3),
the weight ratio (b2)/(b1) of the scaly colored aggregate (b1) to the granular translucent aggregate (b2) is 5/1 to 180/1;
the weight ratio (b3)/(b1) of the scaly colored aggregate (b1) to the granular opaque colored aggregate (b3) is 10/1 to 200/1;
the weight ratio (b3)/(b2) of the granular translucent aggregate (b2) to the granular opaque colored aggregate (b3) is 0.1/1 to 5/1;
The above-mentioned scaly colored aggregate (b1) is obtained by coloring scaly base particles,
The granular translucent aggregate (b2) has a light transmittance of 3% or more and 50% or less,
The coating material is characterized in that the granular opaque colored aggregate (b3) has a light transmittance of less than 3%. The coating material according to claim 1 , characterized in that the granular translucent aggregate (b2) includes a granular translucent aggregate (b2') having an average particle size of 1 μm or more and less than 150 μm. A method for forming a coating film, comprising applying the coating material according to any one of claims 1 and 2 onto a substrate to form a coating film.