JP6841614B2 - Aqueous dressing - Google Patents

Description

The present invention relates to an aqueous coating material having excellent moisture absorption and desorption properties.

In recent years, there has been increasing interest in comfortable living spaces. For example, in the surface finishing of interior surfaces such as walls and ceilings, there are increasing expectations for moisture-absorbing and desorbing finishing materials having functions such as prevention of dew condensation, prevention of mold generation, and suppression of discomfort by adjusting humidity.

As a finishing material having a moisture absorbing / releasing property, for example, Patent Document 1 describes a coating material to which a moisture absorbing / releasing material granule is added. Specifically, a coating material containing an acrylic resin emulsion, water, and moisture absorbing / releasing material granules is described.

JP-A-2003-155786 (Claim 1, paragraph 0030)

However, the finished appearance of the covering material as in Patent Document 1 is a single color tone, and there is a limit in terms of aesthetics. There is also room for improvement in terms of moisture absorption and desorption.

The present invention has been made in view of such problems, and an object of the present invention is to obtain a water-based coating material having excellent aesthetics, moisture absorption and desorption, and the like.

As a result of diligent studies to solve the above problems, the present inventors have come up with an aqueous coating material containing a synthetic resin emulsion, a moisture-absorbing / releasing powder, a specific powder or granular material and an aggregate as essential components, and the present invention has been made. Has come to be completed.

That is, the present invention has the following features.
1. 1. A water-based coating material that absorbs and desorbs moisture.
Synthetic resin emulsion (A),
Moisture absorbing / releasing powder (B) with an average particle size of 5 μm or more and 200 μm or less,
Containing powder or granular material (C) having an average particle diameter of 0.4 μm or more and less than 80 μm and a refractive index of 1.4 or more and 2.0 or less, and an aggregate (D) having an average particle diameter of 80 μm or more.
The moisture-absorbing and desorbing powder (B) includes boehmite, silica gel, zeolite, sodium sulfate, alumina, allophane, diatomaceous earth, siliceous shale, sepiolite, attabargite, montmorillonite, zonolite, imogolite, Otani stone powder, activated white clay, charcoal, bamboo charcoal, Contains one or more selected from activated carbon, wood flour, shell powder, and porous synthetic resin grains.
The above-mentioned aggregate (D) contains at least two kinds of differently colored aggregates, or colored aggregates and transparent aggregates (excluding siliceous shale) .
An aqueous coating material having a weight ratio [(C) / (D)] of the powder or granular material (C) and the aggregate (D) of 0.1 / 1 to 10/1.
2. 2. With respect to 100 parts by weight of the solid content of the synthetic resin emulsion (A)
5 parts by weight or more and 500 parts by weight or less of the moisture absorbing / releasing powder (B),
1. The powder or granular material (C) and the aggregate (D) are contained in a total amount of 100 parts by weight or more and 3000 parts by weight or less. The water-based dressing described.

The water-based coating material of the present invention exhibits excellent aesthetics, moisture absorption and desorption, etc. in the formed coating film.

Hereinafter, modes for carrying out the present invention will be described.

The aqueous coating material of the present invention contains a synthetic resin emulsion (A), a moisture-absorbing / releasing powder (B), an average particle size of 0.4 μm or more and less than 80 μm, and a refractive index of 1.4 or more and 2.0 or less. It contains a granular material (C) and an aggregate (D) having an average particle diameter of 80 μm or more.

The synthetic resin emulsion (A) (hereinafter, also referred to as “component (A)”) acts as a binder, and is, for example, an acrylic resin emulsion, a urethane resin emulsion, a vinyl acetate resin emulsion, an ethylene resin emulsion, or a silicon resin emulsion. , Epoxy resin emulsion, fluororesin emulsion, acrylic / vinyl acetate resin emulsion, acrylic / urethane resin emulsion, acrylic / silicon resin emulsion, acrylic / fluororesin emulsion, etc., and one or more of these may be used. Can be done.

As the component (A), an emulsion polymer of a group of monomers containing an alkyl (meth) acrylate and / or an aromatic group-containing monomer as a main component is suitable. Known alkyl (meth) acrylates and aromatic group-containing monomers can be used. In the present invention, the acrylic acid alkyl ester and the methacrylic acid alkyl ester are collectively referred to as alkyl (meth) acrylate.

Further, in the present invention, it is preferable to include a hydrophobic monomer in the monomer group constituting the component (A). Examples of the hydrophobic monomer include long-chain alkyl (meth) acrylates and aromatic group-containing monomers.

As the long-chain alkyl (meth) acrylate, an alkyl (meth) acrylate having an alkyl group having 6 or more carbon atoms can be used, and for example, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and octyl (meth). Examples thereof include acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate, octadecyl (meth) acrylate, and cyclohexyl (meth) acrylate. Examples of the aromatic group-containing monomer include styrene-based monomers such as styrene, 2-methylstyrene, vinyltoluene, ethylvinylbenzene, vinylnaphthalene, and chlorostyrene, phenyl (meth) acrylate, benzyl (meth) acrylate, and phenoxyethyl ( Examples thereof include aromatic group-containing (meth) acrylates such as meta) acrylates. These can be used alone or in combination of two or more.

In the present invention, it is particularly preferable that the hydrophobic monomer contains an alkyl (meth) acrylate having an alkyl group having 6 or more carbon atoms (preferably 8 or more carbon atoms).

The content of the hydrophobic monomer in the monomer group is preferably 10% by weight or more, more preferably 30% by weight or more, still more preferably 40% by weight or more in terms of weight ratio. The upper limit is not particularly limited, but is preferably 99.5% by weight or less. In such a case, the compatibility with the hydrophobic substance described later is enhanced, and the effect of the present invention can be enhanced.

The glass transition temperature of the component (A) is not particularly limited, but is preferably −40 ° C. or higher and 80 ° C. or lower, and more preferably −30 ° C. or higher and 50 ° C. or lower. The glass transition temperature is a value obtained by the Fox calculation formula.

The average particle size of the component (A) is not particularly limited, but is preferably 10 nm or more and 500 nm or less, more preferably 50 nm or more and 400 nm or less, and further preferably 100 nm or more and 300 nm or less. Such a component (A) is suitable in terms of improving moisture absorption and desorption. The average particle size of the synthetic resin emulsion is a value measured by a dynamic light scattering method. Specifically, it can be measured using a dynamic light scattering measuring device (“LB-550” manufactured by HORIBA, Ltd.) or the like. (Measurement temperature is 25 ° C.)

The component (A) may be produced by a known emulsion polymerization method. For example, as an emulsification polymerization method, it can be produced by a method such as batch polymerization, monomer dropping polymerization, emulsifying monomer dropping polymerization or the like. Further, during the production of the component (A), for example, anionic emulsifiers, nonionic emulsifiers, cationic emulsifiers, amphoteric emulsifiers and other emulsifiers, azo-based initiators, peroxide-based initiators, persulfate initiators, redox initiators, etc. Initiators such as photopolymerization initiators and reactivity initiators, as well as solvents, dispersants, emulsion stabilizers, polymerization inhibitors, polymerization inhibitors, buffers, cross-linking agents, pH adjusters, chain transfer agents, catalysts, etc. Can be added in a required amount according to the purpose. The solid content of the component (A) is preferably 10% by weight or more and 65% by weight or less, and more preferably 30% by weight or more and 60% by weight or less. As the component (A), a medium containing water may be basically used.

The moisture-absorbing and desorbing powder (B) used in the present invention (hereinafter, also referred to as "component (B)") imparts moisture-absorbing and desorbing properties. Such a component (B) has a hygroscopicity of preferably 5% or more, more preferably 10% or more at a temperature of 20 ° C. and a relative humidity of 90%. The hygroscopicity is defined by drying a sample in a constant temperature and humidity chamber with a temperature of 20 ° C. and a relative humidity of 45% for 24 hours, and then allowing the sample to absorb moisture in a constant temperature and humidity chamber with a temperature of 20 ° C. and a relative humidity of 90% for 24 hours. It is a value obtained from the change in weight at the time. That is,
Hygroscopicity (%) = {(Weight after moisture absorption-Weight after drying) / Weight after drying} x 100

The components (B) include, for example, boehmite, silica gel, zeolite, sodium sulfate, alumina, allophen, diatomaceous earth, siliceous shale, sepiolite, attabargite, montmorillonite, zonolite, imogolite, Otani stone powder, activated clay, charcoal, bamboo charcoal, activated carbon, etc. Examples thereof include charcoal powder, shell powder, porous synthetic resin grains, and the like. In the present invention, one or more selected from boehmite, silica gel, zeolite, diatomaceous earth, siliceous shale, and the like can be preferably used.

The average particle size of the component (B) is not particularly limited, but is preferably 1 μm or more and 1000 μm or less, more preferably 5 μm or more and 500 μm or less, still more preferably 10 μm or more and 200 μm or less, and most preferably 15 μm or more and 150 μm or less. The average particle size of the moisture absorbing / releasing powder can be measured by a laser diffraction type particle size distribution measuring device.

The mixing ratio of the component (B) is preferably 5 parts by weight or more and 500 parts by weight or less, more preferably 8 parts by weight or more and 400 parts by weight or less, and further preferably 10 parts by weight with respect to 100 parts by weight of the solid content of the component (A). More than 300 parts by weight or less. Within such a range, excellent moisture absorption and desorption can be exhibited, and it is also suitable in terms of water resistance, cleaning resistance, strength and the like.

In the aqueous coating material of the present invention, a powder or granular material (C) having an average particle diameter of 0.4 μm or more and less than 80 μm and a refractive index of 1.4 or more and 2.0 or less (hereinafter, also referred to as “component (C)”), and an average particle diameter. An aggregate (D) having a diameter of 80 μm or more (hereinafter, also referred to as “component (D)”) is used. In the present invention, by using these components (C) and (D) in combination, excellent performance in terms of aesthetics, moisture absorption and desorption, and the like can be obtained. Although the mechanism of action is not clear, the component (C) having the above physical characteristics exhibits transparency in the film, so that the component (D) almost inhibits the color development while giving a feeling of depth to the film. It is thought that it will not. Further, the component (C) is considered to contribute to the formation of pores serving as a water vapor passage path in the coating film. It is presumed that the effect of the present invention is exerted by the involvement of such an action mechanism.

The average particle size of the component (C) is 0.4 μm or more and less than 80 μm, preferably 0.5 μm or more and 75 μm or less, more preferably 1 μm or more and 60 μm or less, and further preferably 2 μm or more and 45 μm or less. The average particle size of the component (C) can be measured by a laser diffraction type particle size distribution measuring device.

The refractive index of the component (C) is 1.4 or more and 2.0 or less, preferably 1.45 or more and 1.7 or less. The refractive index can be measured using an Abbe refractometer.

Specific examples of the component (C) include inorganic powders and granules such as aluminum silicate, magnesium silicate, barium sulfate, silicon dioxide and calcium carbonate, and organic powders and granules such as resin particles. Also, these are usually uncolored products. It is also desirable that these are medium entities. As the component (C) in the present invention, inorganic powder or granular material is particularly suitable.

The component (D) in the present invention can impart aesthetic appearance such as multicolored feeling and unevenness depending on its particle characteristics. Examples of the component (D) include various aggregates such as crushed natural stone, crushed ceramic, crushed ceramic, crushed glass, glass beads, crushed resin, resin beads, and metal grains. Among these, examples of crushed natural stones include crushed materials such as marble, granite, serpentinite, granite, fluorite, cold water stone, plagioclase, silica stone, and silica sand. Examples of the component (D) include those in which the surface of such various aggregates is color-coated by surface treatment with, for example, a pigment, a dye, a glaze, or the like (colored aggregate). Such aggregates can be used alone or in combination of two or more. As the component (D), it is desirable that at least a colored aggregate is contained, and it is more desirable that at least two or more kinds of colored aggregates having different colors are contained. Further, as the component (D), a colored aggregate and a transparent aggregate can be combined. Further, as the component (D), a chromatic color component and an achromatic color component may be combined. Such a component (D) is suitable in terms of improving aesthetics.

The average particle size of the component (D) is 80 μm or more, preferably 80 μm or more and 1000 μm or less, and more preferably 90 μm or more and 800 μm or less. The average particle size of the component (D) is a value obtained by sieving using a metal net sieve specified in JIS Z8801-1: 2000 and calculating the average value of the weight distribution thereof.

In the present invention, the weight ratio [(C) / (D)] of the component (C) to the component (D) is 0.1 / 1 to 10/1, preferably 0.2 / 1 to 5/1. It is preferably set to 0.3 / 1-3 / 1. As a result, excellent physical properties can be obtained in terms of aesthetics, moisture absorption and desorption, and the like. If this weight ratio [(C) / (D)] is too small, the aesthetic appearance such as the feeling of depth in the finished appearance becomes insufficient, and it becomes difficult to obtain the effect of improving the moisture absorption / desorption property. If the weight ratio [(C) / (D)] is too large, the color-developing property due to the component (D) tends to be insufficient, which may hinder the painting workability and the like.

The total amount of the component (C) and the component (D) is preferably 100 parts by weight or more and 3000 parts by weight or less, more preferably 500 parts by weight or more and 2500 parts by weight or less, based on 100 parts by weight of the solid content of the component (A). is there. If the total amount of the component (C) and the component (D) is such a mixing ratio, it is more suitable in terms of aesthetics, moisture absorption and desorption, etc., and film-forming property, water resistance, crack resistance, and painting work. It is also advantageous in terms of sex and the like.

In addition to the above components, the aqueous coating material of the present invention contains a hydrophobic substance (E) having a solubility in water (water temperature of 20 ° C.) of 10 g / 100 g or less and a boiling point of 200 ° C. or more (hereinafter, also referred to as “component (E)”). Can include. Such a component (E) is suitable in terms of improving moisture absorption and desorption. The solubility of the component (E) in water is preferably 5 g / 100 g or less, more preferably 1 g / 100 g or less, further preferably 0.1 g / 100 g or less, most preferably 0.08 g / 100 g or less, and the boiling point is It is preferably 240 ° C. or higher, more preferably 260 ° C. or higher.

Examples of the component (E) include ethylene glycol monohexyl ether, ethylene glycol dibutyl ether, diethylene glycol monohexyl ether, diethylene glycol monobutyl ether acetate, diethylene glycol dibutyl ether, propylene glycol phenyl ether, dipropylene glycol monobutyl ether, and dipropylene glycol tertiary. Butyl ether, tripropylene glycol monobutyl ether, octylene glycol, 2-ethylhexylene glycol, 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, 2,2,4-trimethyl-1,3- Examples thereof include pentandiol diisobutyrate and benzyl alcohol. These can be used alone or in combination of two or more. In the present invention, the component (E) preferably contains 2,2,4-trimethyl-1,3-pentanediol diisobutyrate.

Although the mechanism of action of the component (E) is not clear, it is considered that the component (E) is present in the synthetic resin emulsion in the vicinity of the resin particles more than in the water, and the aqueous coating material is stored or stored. It is considered that the resin particles are suppressed from entering the moisture absorbing / releasing powder during the film formation. As a result, it is considered that the original moisture absorbing / releasing property of the moisture absorbing / releasing powder can be sufficiently exhibited. When the component (A) contains a hydrophobic monomer as a constituent component thereof, it is considered that such an action is particularly advantageous.

The mixing ratio of the component (E) is preferably 0.1 parts by weight or more and 40 parts by weight or less, and more preferably 1 part by weight or more and 30 parts by weight or less with respect to 100 parts by weight of the solid content of the component (A). In such a range, it is suitable in terms of improving moisture absorption and desorption.

In the water-based coating material of the present invention, in addition to the above components, powders and granules other than the above components (C) and (D), aggregates and the like can also be used. For example, it is possible to give an accentuated aesthetic appearance by appropriately mixing a large particle size aggregate, a scaly aggregate, or the like.

Further, the aqueous coating material of the present invention may contain, for example, a coloring pigment, a hollow bead, a plasticizing agent, a film-forming auxiliary, an antifreeze agent, a preservative, a fungicide, an antibacterial agent, an antifoaming agent, and a pigment dispersant. , Thickeners, leveling agents, wetting agents, pH regulators, fibers, matting agents, UV absorbers, antioxidants, light stabilizers, adsorbents, catalysts, cross-linking agents, etc. Can be used in combination with appropriate components. Water, a solvent and the like can be mixed with the water-based coating material of the present invention, if necessary.

In the present invention, it is desirable that the mixing ratio of the coloring pigment and the hollow beads is suppressed to such an extent that the aesthetic appearance of the component (D) is not impaired. The total amount of the coloring pigment and the hollow beads is preferably 30 parts by weight or less, more preferably 10 parts by weight or less, still more preferably 5 parts by weight or less, based on 100 parts by weight of the solid content of the component (A). An embodiment that does not contain coloring pigments and hollow beads is also preferable.

The water-based coating material of the present invention exhibits moisture absorption and desorption in the formed film. Moisture absorption and desorption can be measured by the amount of moisture absorption and desorption according to JIS A 6909: 2014 "Building Finishing Coating Material" 7.29. The amount of moisture absorbed and released from the coating material of the present invention is preferably 20 g / m ² or more, more preferably 60 g / m ² or more, still more preferably 70 g / m ² or more, and most preferably 80 g / m ² or more.

The water-based coating material of the present invention can be mainly used as a surface finishing material for interior surfaces such as walls and ceilings. The base material constituting the wall, ceiling, etc. is not particularly limited, but for example, concrete, mortar, slate board, calcium silicate board, ALC board, extruded board, gypsum board, brick, porcelain tile, siding board, metal plate. , Plywood, etc. Further, these base materials may be those to which some surface treatment (sealer, surfacer, filler, putty, etc.) has been applied, or those having an existing coating film or the like.

Coating with the amount of the aqueous coating material, depending on the kind of pattern to be formed, preferably 0.1 kg / ^{m 2} or more 4 kg / ^{m 2} or less, more preferably 0.2 kg / ^{m 2} or more 3 kg / ^{m 2} It is about the following. Within the range of such a coating amount, it is also possible to apply the coating in a plurality of times. The coating tool is not particularly limited, and for example, a spray, a roller, a trowel, a brush, or the like can be used. At the time of application, a diluent such as water may be mixed to appropriately adjust the viscosity. The dilution ratio is preferably 0% by weight or more and 10% by weight or less. Painting and subsequent drying may be preferably performed at 0 ° C. or higher and 40 ° C. or lower (normal temperature).

Examples are shown below to clarify the features of the present invention.

(Example 1)
Using the raw materials shown in Table 1, each raw material was mixed and stirred by a conventional method according to the formulation shown in Table 2 to produce an aqueous coating material.

A water-based coating material (stored for 1 day after production) is coated on a sealer-treated slate plate (base material) with a trowel at a coating rate of 1.5 kg / m ² to prepare a test piece. did. The production and storage of the aqueous coating material and the preparation of the test piece were all carried out in an environment of a temperature of 23 ° C. and a relative humidity of 50%. The following test was carried out on the obtained water-based coating material.

(1) Finished appearance The finished appearance of the above test piece was visually evaluated. The evaluation was carried out on a three-point scale (A>B> C) in which those having a natural stone-like multicolored feeling were designated as "A" and those lacking a multicolored feeling were designated as "C".

(2) Moisture absorption and desorption 1
After sealing the side surface and the back surface of the test piece with an aluminum adhesive tape, the moisture absorption / desorption amount (g / m ² ) was measured according to the procedure of JIS A 6909: 2014 “Building finish coating material” 7.29. The evaluation criteria are as follows. The results are shown in Table 2.
A: Moisture absorption / desorption amount 80g / m ² or more B: Moisture absorption / desorption amount 70g / m ² or more and less than 80g / m ² C: Moisture absorption / desorption amount 60g / m ² or more and ^{less than 70g / m 2} D: Moisture absorption / desorption amount 60g Less than / m ²

(3) Moisture absorption and desorption 2
A test piece was prepared in the same manner as in the above-mentioned moisture absorption / desorption property 1 except that an aqueous coating material stored in an environment of 50 ° C. for 7 days after production was used, and the amount of moisture absorption / desorption was measured. The results are shown in Table 2.

(Examples 2 to 11, Comparative Examples 1 to 2)
An aqueous coating material was produced by the same method as in Example 1 except for the formulations shown in Table 2, and the same test as in Example 1 was carried out. The results are shown in Table 2.

Claims (2)

A water-based coating material that absorbs and desorbs moisture.
Synthetic resin emulsion (A),
Moisture absorbing / releasing powder (B) with an average particle size of 5 μm or more and 200 μm or less,
Containing powder or granular material (C) having an average particle diameter of 0.4 μm or more and less than 80 μm and a refractive index of 1.4 or more and 2.0 or less, and an aggregate (D) having an average particle diameter of 80 μm or more.
The moisture-absorbing and desorbing powder (B) includes boehmite, silica gel, zeolite, sodium sulfate, alumina, allophane, diatomaceous earth, siliceous shale, sepiolite, attabargite, montmorillonite, zonolite, imogolite, Otani stone powder, activated white clay, charcoal, bamboo charcoal, Contains one or more selected from activated carbon, wood flour, shell powder, and porous synthetic resin grains.
The above-mentioned aggregate (D) contains at least two kinds of differently colored aggregates, or colored aggregates and transparent aggregates (excluding siliceous shale) .
An aqueous coating material having a weight ratio [(C) / (D)] of the powder or granular material (C) and the aggregate (D) of 0.1 / 1 to 10/1. With respect to 100 parts by weight of the solid content of the synthetic resin emulsion (A)
5 parts by weight or more and 500 parts by weight or less of the moisture absorbing / releasing powder (B),
The water-based coating material according to claim 1, wherein the powder or granular material (C) and the aggregate (D) are contained in a total amount of 100 parts by weight or more and 3000 parts by weight or less.