JP2020000992A - Coating method of structure - Google Patents

Abstract

To provide a coating method of a non-aqueous normal temperature-drying structure which is low in odor and is excellent in drying property and coating workability.SOLUTION: A coating method of a structure includes a step of coating a structure or a surface of its member with a coating composition and forming a coating film, in which the coating composition contains an organic solvent (A) and a resin (B), the organic solvent (A) contains 90 mass% or more of the organic solvent (A1) with a vapor pressure at 20°C of 10-120 Pa, and the resin (B) is formed of at least one resin in a resin dispersible in the organic solvent (A) and a resin soluble in the organic solvent (A).SELECTED DRAWING: None

Description

  The present invention relates to a method for coating a structure, and more particularly to a method for coating a non-aqueous room-temperature-dried structure having low odor and excellent drying properties and coating workability.

  Paints for interior and exterior of buildings are widely used from organic solvent-based paints to water-based paints. Although the paint industry has proposed many shifts to water-based paints in order to improve the working environment, etc., for coatings intended for buildings, the use of organic solvents has been considered in terms of coating workability and drying properties. In many cases, system paints are used. Here, one of the problems of the organic solvent-based paint is a problem of odor due to the organic solvent, and an organic solvent-based paint that addresses such a problem is being studied.

  WO 2005/000979 (Patent Document 1) discloses (A) at least one kind of paint resin selected from the group consisting of an epoxy resin, a urethane resin and an acrylic resin, (B) a low-odor organic solvent, C) At least one compound selected from the group consisting of esters and / or lactones having 8 or more carbon atoms and, if necessary, (D) a curing agent for a coating resin (A). It describes a low odor solvent-based coating composition characterized by being substantially free of xylene and toluene, which remarkably suppresses paint odor generated after drying of a coating film. The coating composition described in Patent Document 1 is considered to have achieved a low odor due to the feature that xylene and toluene are not substantially used. However, in place of the solvent causing the odor, butyl acetate and other solvents are used. (B) a low odor organic solvent composed of the organic solvent described above, and a compound (C) having an odor neutralizing property.

  On the other hand, it is desirable to use a room temperature drying type paint for interior and exterior of buildings. For example, Japanese Patent Application Laid-Open No. 2006-188639 (Patent Document 2) discloses that (A) a third type organic solvent and (B) a soluble in the organic solvent (A), a hydroxyl value exceeds 5 mgKOH / g, and It describes a curable fluorine-containing coating composition comprising a hydroxyl-containing fluorine-containing copolymer having a total of a hydroxyl value and an acid value of more than 30 mgKOH / g, and thereby exhibits sufficient dry curability even at room temperature, It is said that a composition for a fluorine-containing coating which is excellent in solvent resistance, water resistance, weather resistance and the like and is environmentally friendly can be provided.

International Publication No. 2005/000979 JP 2006-188639 A

  However, although the coating composition described in Patent Literature 1 suppresses odor in that xylene and toluene are not substantially used, strong odor due to the organic solvent used is recognized, and there is still room for improvement. is there. Further, Patent Document 1 describes only a heat-curable paint, and has not been sufficiently studied as a normal-temperature-dry paint.

  Further, the coating composition described in Patent Document 2 shows sufficient drying curability even at room temperature and uses a third type organic solvent as an environmentally friendly organic solvent. The use of seed organic solvents does not address the problem of odor.

  In addition, in a situation where the temperature of the surface of a structure rises in summer or the like, if the coating material has excellent drying properties at normal temperature, the drying speed is too fast, so that the coating is often difficult. In particular, in the repainting of the curtain wall used for the wall of the building, the paint is less scattered, roller coating is preferred from the viewpoint of reducing paint waste, but roller coating is performed on paint that is too fast drying. Then, there is a problem that gloss unevenness and the like are likely to occur, and coating workability is remarkably reduced.

  Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art, and to provide a method for coating a non-aqueous room-temperature drying type structure having low odor, excellent drying property and excellent coating workability.

  The present inventors have conducted intensive studies to achieve the above object, and as a result, a non-aqueous room-temperature-drying coating composition in which an organic solvent having a specific vapor pressure and a resin dispersible or dissolvable in the organic solvent are combined. However, with a low odor, and excellent in drying properties, even when performing roller coating under a situation where the temperature of the surface of the structure increases in the summer, etc., it is found that the coating workability is excellent, and the present invention is completed. Reached.

That is, the method for coating a structure of the present invention includes a step of coating the surface of the structure or a member thereof with a coating composition to form a coating film,
The coating composition contains an organic solvent (A) and a resin (B), and the organic solvent (A) contains 90% by mass or more of an organic solvent (A1) having a vapor pressure of 10 to 120 Pa at 20 ° C, The resin (B) is characterized by comprising at least one of a resin dispersible in the organic solvent (A) and a resin soluble in the organic solvent (A).

  In a preferred example of the method for coating a structure according to the present invention, the structure is a building.

  In another preferred embodiment of the method for coating a structure according to the present invention, the coating composition is a cold-drying coating composition.

  In another preferred embodiment of the method for coating a structure according to the present invention, the means for coating the coating composition is a roller.

  In another preferred embodiment of the method for coating a structure according to the present invention, the thickness of the coating film is 20 to 50 μm.

  In another preferred embodiment of the method for coating a structure according to the present invention, the amount of water in the coating composition is less than 1.0% by mass.

  In another preferred embodiment of the method for coating a structure according to the present invention, the resin (B) contains 50% by mass or more of the resin (B1) having a weight average molecular weight of 800 to 300,000.

  In another preferred embodiment of the method of coating a structure according to the present invention, the method further comprises, before the step, a step of coating the surface of the structure or a member thereof with an undercoat paint to form an undercoat film.

  Advantageous Effects of Invention According to the present invention, it is possible to provide a method for coating a non-aqueous, room-temperature-dried structure having low odor and excellent drying property and coating workability.

  Hereinafter, the method for coating a structure according to the present invention will be described in detail. The coating method of a structure of the present invention includes a step of coating a surface of a structure or a member thereof with a coating composition to form a coating film, wherein the coating composition comprises an organic solvent (A) and a resin (B). The organic solvent (A) contains 90% by mass or more of an organic solvent (A1) having a vapor pressure of 10 to 120 Pa at 20 ° C., and the resin (B) is dispersible in the organic solvent (A). And at least one of a resin soluble in the organic solvent (A) and a resin soluble in the organic solvent (A). In addition, the said coating composition is also called coating composition (X).

  Since the coating composition (X) contains the organic solvent (A) containing 90% by mass or more of the organic solvent (A1) having a vapor pressure of 10 to 120 Pa at 20 ° C., it is suitable as a room temperature drying type coating composition. After coating on the substrate, it is possible to form a coating film by drying at room temperature. The “normal temperature” here is 5 to 35 ° C., and according to the above-mentioned coating composition (X), drying in a short time of 24 hours or less at 23 ° C. or 48 hours or less even at 5 ° C. Is also possible.

  Further, since the coating composition (X) contains the organic solvent (A) containing 90% by mass or more of the organic solvent (A1) having a vapor pressure of 10 to 120 Pa at 20 ° C., the organic solvent-based (in other words, non- (Aqueous) coating composition. The term "organic solvent-based coating composition" as used herein means a coating composition in which the proportion of the organic solvent in the entire solvent contained in the coating composition is 50% by mass or more. In particular, the coating composition (X) preferably has a water content of less than 1.0% by mass from the viewpoint of ensuring good drying properties. In addition, the water content refers to the content of water in the coating composition.

  Examples of the organic solvent (A) used in the coating composition (X) include alcohols, ethers, ketones, esters (including lactones), nitrogen-containing compounds (amides, lactams, etc.), sulfur-containing compounds, and hydrocarbons. Known paint solvents such as (aliphatic hydrocarbons, alicyclic hydrocarbons, and aromatic hydrocarbons) can be used. In the above-mentioned paint composition (X), the solvent constituting the organic solvent (A) can be used. 90% by mass or more, preferably 93% by mass or more, more preferably 95% by mass or more, and most preferably 100% by mass is an organic solvent (A1) having a vapor pressure of 10 to 120 Pa at 20 ° C. Among these organic solvents, oxygen-containing compounds (eg, alcohols, ethers, ketones, esters, etc.) are particularly preferable from the viewpoint of dispersing or dissolving the resin (B) and a curing agent described below. The organic solvents may be used alone or in combination of two or more. In the coating composition (X), the content of the organic solvent (A) is preferably, for example, 15 to 90% by mass.

  In the coating composition (X), the organic solvent (A1) has a vapor pressure of 10 to 120 Pa at 20 ° C. The present inventor has found that when a substance having a low vapor pressure is used as a solvent for the coating composition, it is difficult to feel the odor generated from the coating composition and its coating film during drying. According to the coating composition (X), since an organic solvent having a vapor pressure at 120C of 120 Pa or less is used, the odor from the coating composition and its coating film can be suppressed, and the surface of the structure in summer or the like can be suppressed. Evaporation does not become too fast even in a situation where the temperature rises. The vapor pressure at 20 ° C. is preferably 120 Pa or less, more preferably 100 Pa or less. On the other hand, the vapor pressure of the organic solvent (A1) at 20 ° C. is 10 Pa or more, preferably 50 Pa or more. If the vapor pressure at 20 ° C. is an organic solvent having a pressure of 10 to 120 Pa, it is possible to evaporate by drying at room temperature, and the evaporation may be too fast even in a situation where the temperature of the surface of the structure increases, such as in summer. No paint workability.

  Specific examples of the organic solvent (A1) having a vapor pressure of 10 to 120 Pa at 20 ° C. include n-octanol, ethylhexyl alcohol, 3-methoxy-3-methylbutanol, 3-methoxy-3-methylbutyl acetate, Methyl-1,3-propanediol, dimethylpropylene glycol, ethylene glycol monobutyl ether, ethylene glycol monobutyl ether acetate, ethylene glycol monoisobutyl ether, ethylene glycol monohexyl ether, ethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol ethyl methyl ether, Diethylene glycol diethyl ether, diethylene glycol butyl methyl ether, diethylene glycol isopropyl Butyl ether, propylene glycol monobutyl ether, diethylene glycol monobutyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol monopropyl ether, dipropylene glycol dimethyl ether, triethylene glycol dimethyl ether, N-methyl-2-pyrrolidone, isoparaffin hydrocarbon, hexyl glycol And the like. These solvents may be used alone or in combination of two or more.

  Since the coating composition (X) contains an organic solvent (A) as a solvent, the coating composition (X) contains, as a resin, a resin dispersible in the organic solvent (A) and the organic solvent (A). ) Includes a resin (B) made of at least one of the resins soluble in the resin. Here, the “resin dispersible in the organic solvent (A)” is a resin that can be distributed in the organic solvent (A) to form a heterogeneous system (for example, an emulsion or a suspension). It is a resin dispersed in the composition (X). The term “resin soluble in the organic solvent (A)” refers to a resin that is soluble in the organic solvent (A), and a mixture with the organic solvent (A) forms a uniform solution, It is a resin dissolved in the coating composition (X). When dispersing or dissolving the resin (B) in the organic solvent (A), additives such as a dispersant and an emulsifier may be used.

  In the coating composition (X), the resin (B) preferably contains the resin (B1) having a weight average molecular weight of 800 to 300,000. If the molecular weight is within the above-specified range, it is necessary to achieve both good dispersibility and solubility in the organic solvent (A) used in the coating composition (X) and good coating film properties (drying property, water resistance, etc.). Can be. Further, the weight average molecular weight of the resin (B1) is more preferably 900 to 100,000. In the present invention, the weight average molecular weight is a value measured by gel permeation chromatography, and polystyrene is used as a standard substance.

  In the coating composition (X), the proportion of the resin (B1) in the resin (B) is preferably 50% by mass or more, and more preferably 80% by mass or more. When the proportion of the resin (B1) in the resin (B) is 50% by mass or more, the effect exerted by the molecular weight in the above specified range can be enhanced.

  Examples of the resin (B) used in the coating composition (X) include resins commonly used in the coatings industry. Specifically, acrylic resins, silicone resins, acrylic silicone resins, and styrene acrylic resins Polymerized resin, polyester resin, fluororesin, rosin resin, petroleum resin, coumarone resin, phenolic resin, urethane resin, melamine resin, urea resin, epoxy resin, cellulose resin, xylene resin, alkyd resin, aliphatic hydrocarbon resin, butyral resin , Maleic acid resin, fumaric acid resin, vinyl resin, amine resin, ketimine resin and the like. Among them, a fluororesin, a urethane resin, a silicone resin, an acrylic resin, an acrylic silicone resin, an epoxy resin and an alkyd resin are preferable, and a fluororesin, a silicone resin, an acrylic resin and an acrylic silicone resin are particularly preferable. These resins may be used alone or in combination of two or more.

  In the coating composition (X), the content of the resin (B) in the nonvolatile components is preferably, for example, 20 to 100% by mass. When the coating composition further contains a pigment or the like, the content is 20 to 98%. It is preferably mass%. Here, the non-volatile content refers to a component excluding volatile components such as water and an organic solvent, and is a component that will eventually form a coating film. Components remaining after drying at 60 ° C. for 60 minutes are treated as nonvolatile components. In the coating composition (X), the nonvolatile content is preferably from 10 to 85% by mass.

  The coating composition (X) can include a pigment. The pigment that can be used in the present invention is not particularly limited, and pigments commonly used in the paint industry can be used. Specific examples include coloring pigments such as titanium dioxide, iron oxide, and carbon black; extender pigments such as silica, talc, mica, calcium carbonate, and barium sulfate; zinc, zinc phosphate, aluminum phosphate, aluminum tripolyphosphate, and molybdic acid. Rust-preventive pigments such as zinc, barium metaborate, and hydrocalumite; and bright pigments such as aluminum, nickel, chromium, tin, copper, silver, platinum, gold, stainless steel, and glass flakes. These pigments may be used alone or in combination of two or more. In the coating composition (X), the content of the pigment in the nonvolatile components is preferably, for example, 1 to 80% by mass.

The coating composition (X) can include a curing agent. The curing agent that can be used in the present invention is appropriately selected according to the type of the resin used, and a curing agent that is commonly used in the paint industry can be used. These curing agents may be used alone or in combination of two or more. The content of the curing agent is appropriately adjusted according to the amount of the reactive group with the curing agent contained in the resin. However, in the coating composition (X), the content of the curing agent in the nonvolatile components Is preferably, for example, 0.5 to 15% by mass.
For example, an isocyanate-based curing agent can be suitably used for a resin containing a hydroxyl group (eg, a hydroxyl group-containing acrylic resin, a hydroxyl group-containing acrylic silicone resin, and a hydroxyl group-containing fluororesin). Specific examples include tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, xylylene diisocyanate, hexamethylene diisocyanate, 4,4′-methylene bis (cyclohexyl isocyanate), methylcyclohexane diisocyanate, bis (isocyanatomethyl) cyclohexane, isophorone diisocyanate, In addition to dimer acid diisocyanate and lysine diisocyanate, modified products of these polyisocyanates can be mentioned. Specific examples of the modified product include a biuret modified product, an isocyanurate modified product, an adduct modified product (for example, an adduct of trimethylolpropane), an allophanate modified product, and a uretdione modified product.
In addition, an amine-based curing agent can be suitably used for the epoxy resin. Specific examples include aliphatic diamines such as ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, triaminopropane, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, isophoronediamine, and 1,3-bisaminomethylcyclohexane. Polyamines; aromatic polyamines such as phenylenediamine, meta-xylylenediamine, para-xylylenediamine, and diaminodiphenylmethane; other polyamines such as polyoxyethylene diamine, polyoxypropylene diamine, triethylene glycol diamine, and tripropylene glycol diamine Compounds and modified polyamine compounds obtained by modifying the amino groups of these amine compounds. Known methods can be used to modify the amine compound. Examples of the modification reaction include amidation of an amino group, Mannich reaction of an amino group and a carbonyl compound, and addition reaction of an amino group and an epoxy group. Can be Here, a modified polyamine compound in which an epoxy group or the like is added to an amino group is referred to as an adduct-type modified polyamine compound, and an epoxy adduct-type modified polyamine compound in which an epoxy group is added to an amino group is preferable.

  The coating composition (X) includes, as other components, other resins, matting agents, surface conditioners, wetting agents, dispersants, emulsifiers, thickeners, anti-settling agents, anti-skinning agents, anti-sagging agents. Agents, antifoaming agents, anti-coloring agents, leveling agents, desiccants, plasticizers, film-forming aids, fungicides, antibacterial agents, insecticides, light stabilizers, ultraviolet absorbers, antistatic agents and conductivity An imparting agent and the like can be appropriately compounded according to the purpose. Commercially available products can be suitably used for these components.

  The coating composition (X) can be prepared by mixing various components appropriately selected as necessary. When the coating composition (X) is a two-pack coating composition, a main agent and a curing agent are prepared in advance by mixing various components appropriately selected as necessary. It is used by mixing the main agent and the curing agent during painting. The curing agent may be the curing agent itself or a mixture with other components.

The coating composition (X) has a viscosity of 0.1 to 10,000 Pa · s at a shear rate of 0.1 s ^{−1 and} a viscosity of 0.05 to 10 Pa · s at a shear rate of 1,000 s ^−1. Preferably, there is. In the present invention, the viscosity is measured after adjusting the liquid temperature to 23 ° C. using a rheometer ARES manufactured by TA Instruments.

  The coating means of the coating composition (X) is not particularly limited, and known coating means, for example, spray coating, roller coating, brush coating, iron coating, spatula coating and the like can be used. Preferably, roller coating is more preferred.

  The coating film formed from the coating composition (X) preferably has a thickness of 20 to 50 μm.

  In the coating method of the present invention, the structure to be coated includes a building, a structure, and the like, and it is preferable that the structure is a structure built and constructed outdoors (outdoor structure). The coating composition (X) is suitable as a coating for interior and exterior of a structure. In the present invention, a building means a structure constructed for the purpose of inhabiting or staying by humans, for example, a house (especially a detached house or an apartment house), a building, a factory, and the like. A structure constructed for a purpose other than human residence or stay, such as a bridge, a tank, a plant plumbing, or a chimney. In particular, the coating method of the present invention is useful for buildings. The surface of the structure may be subjected to a primer treatment such as an anticorrosion treatment, or an old coating film (a coating film already formed when the coating method of the present invention is performed) may be applied to at least a part of the surface. Film) may be present. Examples of the structural member include a roof and a wall (an inner wall, an outer wall, etc., particularly, a curtain wall).

  The method for coating a structure of the present invention may further include a step of coating the surface of the structure or a member thereof with an undercoat before forming the coating with the coating composition (X) to form an undercoat. it can. In this case, coating with the coating composition (X) is performed on the undercoat film. That is, in one embodiment of the method for coating a structure of the present invention, a step of coating the surface of a structure or a member thereof with an undercoat to form an undercoat, and applying the undercoat to the coating composition (X ) To form a top coat.

  Conventionally known various paints such as an organic solvent-based paint using an organic solvent as a main solvent, an aqueous paint using water as a main solvent, a solvent-free paint, and various enamel paints or clear paints of powder paints are used as the undercoat paint. However, from the viewpoint of achieving the object of the present invention, the undercoat paint is preferably the paint composition described as the paint composition (X).

  Specifically, in the method for coating a structure according to the present invention, the undercoat paint contains an organic solvent (A) and a resin (B), and the organic solvent (A) has a vapor pressure at 20 ° C of 10 to 120 Pa. The resin (B) contains at least 90% by mass of an organic solvent (A1), and the resin (B) is made of at least one of a resin dispersible in the organic solvent (A) and a resin soluble in the organic solvent (A). The coating composition is preferably The coating composition for undercoat paint is also referred to as a coating composition (Y).

  Other embodiments of the coating composition (Y) are as described in the description of the coating composition (X). To give a specific example, the coating composition (Y) is preferably a cold-drying coating composition. Further, the coating composition (Y) preferably has a water content of less than 1.0% by mass. In the coating composition (Y), the resin (B) preferably contains 50% by mass or more of the resin (B1) having a weight average molecular weight of 800 to 300,000.

  In the method for coating a structure according to the present invention, the coating composition (X) and the coating composition (Y) are independent of each other, and they may be the same coating composition or different coating compositions. It may be a thing.

  The means for coating the coating composition (Y) is not particularly limited, and known coating means, for example, spray coating, roller coating, brush coating, iron coating, spatula coating and the like can be used. Preferably, roller coating is more preferred.

  The coating film formed from the coating composition (Y) preferably has a thickness of 20 to 50 μm.

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

[Preparation example of resin]
(Preparation example of acrylic resin solution A)
In a reaction vessel equipped with a stirrer, thermometer, cooling pipe and nitrogen gas introduction pipe, 300 parts by mass of Isopar H (manufactured by Ando Parachemie) were charged and maintained at 110 ° C., and 70 parts by mass of isobutyl methacrylate prepared in advance, A mixture of 230 parts by mass of tert-butyl methacrylate, 150 parts by mass of lauryl methacrylate and 2 parts by mass of benzoyl peroxide was uniformly dropped in 3 hours while maintaining 110 ° C. under a nitrogen atmosphere, and 3 parts by mass of benzoyl peroxide was further charged. The temperature was maintained at 110 ° C. for 1 hour, 250 parts by mass of Isopar H was charged, and an acrylic resin solution A having a nonvolatile content of 45.2% by mass, a weight average molecular weight of 140,000 and a colorless and transparent appearance was obtained.

(Preparation Example of Acrylic Resin Dispersion B)
In a reaction vessel equipped with a stirrer, a thermometer, a cooling pipe and a nitrogen gas introducing pipe, 330 parts by mass of the acrylic resin solution A and 150 parts by mass of Isopar H obtained according to the above preparation example were charged and maintained at 110 ° C. A mixture of 110 parts by mass of methyl methacrylate, 40 parts by mass of ethyl acrylate, 70 parts by mass of butyl acrylate, 50 parts by mass of butyl methacrylate, 40 parts by mass of isobutyl methacrylate and 3 parts by mass of benzoyl peroxide was kept at 110 ° C. under a nitrogen atmosphere. While maintaining the temperature at 110 ° C. for 1 hour, 240 parts by weight of Isopar H was charged, the nonvolatile content was 44.9% by weight, and the weight average molecular weight was about 140. Acrylic resin dispersion B having a white appearance was obtained.

(Preparation example of acrylic resin solution C)
225 parts by mass of Solfit AC (manufactured by Kuraray Co., Ltd.) were charged into a reaction vessel equipped with a stirrer, a thermometer, a cooling pipe and a nitrogen gas introduction pipe, and kept at 100 ° C., and 141 parts by weight of cyclohexyl methacrylate prepared in advance, A mixture of 123 parts by mass of methyl methacrylate, 119 parts by mass of isobutyl methacrylate, 125 parts by mass of 2-ethylhexyl acrylate, 53 parts by mass of 2-hydroxyethyl methacrylate and 6 parts by mass of tertiary butyl peroxy-2-ethylhexanoate was mixed in a nitrogen atmosphere. The mixture was dropped uniformly over 3 hours while maintaining the temperature at 100 ° C., and a mixture of 4 parts by mass of tertiary butyl peroxy-2-ethylhexanoate and 52 parts by mass of Solfit AC was charged at 100 ° C. for 1 hour. Charge 152 mass parts of Fit AC, 7.0 mass%, weight average molecular weight of 50,000, appearance to obtain a colorless transparent acrylic resin solution C.

(Preparation example of acrylic resin solution D)
The same operation as in the preparation example of the acrylic resin solution C, except that Solfit AC was replaced with xylene (Maruzen Petrochemical Co., Ltd.), an acrylic resin having a nonvolatile content of 57.0% by mass, a weight average molecular weight of 50,000 and a colorless and transparent appearance. A resin solution D was obtained.

[Example of paint preparation]
According to the formulation shown in Tables 1 and 2, the main agent was prepared and mixed with a curing agent at the time of coating to prepare coating materials (Examples 1 to 8 and Comparative Examples 1 to 8). In addition, about Examples 9-13, since it is a one-pack type coating composition, the coating material was prepared according to the formulation shown in Table 1. In addition, all of the resins used in the prepared paint were dispersed or dissolved in the paint.

(Note 1) "Lumiflon LF200F": manufactured by Asahi Glass Co., Ltd., fluorine resin, nonvolatile content 100% by mass
(Note 2) "JR-806": manufactured by Teica, titanium oxide (Note 3) "Acemat 82": manufactured by Evonik, silica, average particle diameter 7 μm
(Note 4) “Techpolymer MBX-12”: Sekisui Chemical Co., Ltd., resin beads, average particle diameter 12 μm)
(Note 5) “Solfit AC”: manufactured by Kuraray Co., Ltd., 3-methoxy-3-methyl-1-butyl acetate, vapor pressure 53 Pa
(Note 6) “Solfit”: Kuraray Co., Ltd., 3-methoxy-3-methyl-1-butanol, vapor pressure 47 Pa
(Note 7) "DOWANOL PnB": Dow, propylene glycol monobutyl ether, vapor pressure 113 Pa
(Note 8) "Hysolve EDE": manufactured by Toho Chemical Industry Co., Ltd., diethylene glycol diethyl ether, vapor pressure 50 Pa
(Note 9) "Isopar H": ExxonMobil, isoparaffinic hydrocarbon, vapor pressure 100 Pa
(Note 10) "Duranate TSA100": manufactured by Asahi Kasei Chemicals Corporation, modified with hexamethylene diisocyanate, nonvolatile content 100% by mass
(Note 11) "Lumiflon LF800": manufactured by Asahi Glass Co., Ltd., mineral spirit solution of fluororesin, nonvolatile content 60% by mass
(Note 12) “Butyl diglycol acetate”: manufactured by Daicel, diethylene glycol monobutyl ether acetate, vapor pressure 5 Pa
(Note 13) "PE-AC": Kuraray Co., Ltd., propylene glycol monoethyl ether acetate, vapor pressure 227 Pa
(Note 14) "Xylene": Maruzen Petrochemical Co., Ltd., vapor pressure 900 Pa
(Note 15) “PEGASOL AN 45 FLUID”: ExxonMobil, vapor pressure 287 Pa

[test]
The drying property, odor and coating film appearance were evaluated. The results are shown in Tables 3 and 4.

<Evaluation method for dryness>
The prepared coating material was applied to a glass plate (150 mm × 70 mm × 2 mm) using a film applicator with a gap of 150 μm under each temperature and humidity condition, and the coating material was applied to JIS K 5600-1-1, 4.3.5b). Was measured under the conditions described above, and the drying property was evaluated according to the following evaluation criteria.
(Evaluation criteria of 23 ° C 50% RH)
◎: less than 6 hours ○: 6 hours or more, less than 8 hours Δ: 8 hours or more, less than 24 hours ×: 24 hours or more (evaluation criteria of 23 ° C., 85% RH)
◎: less than 6 hours ○: 6 hours or more, less than 8 hours Δ: 8 hours or more, less than 24 hours ×: 24 hours or more (evaluation criteria of 5 ° C., 30% RH)
◎: less than 16 hours ○: 16 hours or more, less than 32 hours Δ: 32 hours or more, less than 48 hours ×: 48 hours or more

<Odor evaluation method>
The odor was evaluated based on the sensory evaluation and the odor sensor value.
(sensory evaluation)
Transfer 25 to 30 g of the prepared paint to a 50-mL capacity glass bottle and cover it. The opened part of the opened bottle was brought close to the subject's nose for 10 seconds, and the odor was evaluated. The test subjects were five men and five women in their twenties to forties. The odor was scored according to the following scoring criteria, and the value obtained by dividing the total score of ten subjects by 10 was evaluated according to the following evaluation criteria.
<Scoring criteria>
0 point: almost no odor 1 point: slight odor 2 points: odor 3 points: strong odor <Evaluation criteria>
：: less than 1.0 ○: 1.0 or more, less than 1.5 points Δ: 1.5 or more, less than 2.5 points ×: 2.5 or more (odor sensor value)
The paint odor was measured according to the indoor odor measurement test method (odor measurement method using an odor measurement tester (COSMOS, XP-329mR)) proposed by the Tokyo Metropolitan Government Construction Bureau (revised version in 2014). The odor was evaluated according to the following evaluation criteria. The lower the measured value, the lower the odor.
◎: less than 120 ：: 120 or more, less than 200 Δ: 200 or more, less than 300 ×: 300 or more

<Method of evaluating coating film appearance>
The prepared paint is applied to a tin plate (300 mm × mm × 300 mm) adjusted to a substrate temperature of 60 ° C. using a hot plate using a roller having a hair length of 8 mm under the conditions of 23 ° C. and 50% relative humidity. did. After coating, the coating film appearance after drying at 60 ° C. for 60 minutes was visually evaluated. The dry film thickness was adjusted to be 25 μm or 50 μm.
：: No coating unevenness was observed, and a good appearance was obtained.
Δ: Painting unevenness is observed on a part of the painted surface.
×: Uneven coating is observed on most of the painted surface, and the appearance is poor.

Claims (8)

Including a step of coating the surface of the structure or its members with a coating composition to form a coating film,
The coating composition contains an organic solvent (A) and a resin (B), and the organic solvent (A) contains 90% by mass or more of an organic solvent (A1) having a vapor pressure of 10 to 120 Pa at 20 ° C, The method for coating a structure, wherein the resin (B) comprises at least one of a resin dispersible in the organic solvent (A) and a resin soluble in the organic solvent (A).   The method for coating a structure according to claim 1, wherein the structure is a building.   The method for coating a structure according to claim 1, wherein the coating composition is a cold-drying coating composition.   The method for coating a structure according to any one of claims 1 to 3, wherein the coating means of the coating composition is a roller.   The method for coating a structure according to any one of claims 1 to 4, wherein the thickness of the coating film is 20 to 50 m.   The method for coating a structure according to any one of claims 1 to 5, wherein the amount of water in the coating composition is less than 1.0% by mass.   The coating of a structure according to any one of claims 1 to 6, wherein the resin (B) contains 50% by mass or more of the resin (B1) having a weight average molecular weight of 800 to 300,000. Method.   The structure according to any one of claims 1 to 7, further comprising, before the step, coating the surface of the structure or a member thereof with an undercoat paint to form an undercoat film. Painting method.