Painted article, method for manufacturing a painted article, and paint composition

Abstract

The present invention provides a coated article having a mirror design and excellent film properties and radio wave permeability, a production method of the coated article, and a coating composition for the coated article. The coated article is characterized by having (a) a primer coating film layer formed of a primer coating material, which is directly or indirectly provided on a coated article, and (b) a metal-containing coating film layer having a pigment weight concentration (PWC) of 70.0% or more, which is directly or indirectly provided on the primer coating film layer, and in which indium thin film fragments are vapor deposited, and the primer coating material is a two-component curable coating material, an acrylic paint, a melamine-based coating material, or a radiation curable coating material.

Description

TECHNICAL FIELD

[0001] The present application relates to a coated article having a coating film with a mirror design and a radio wave permeability, a method for producing a coated article having a mirror design and a radio wave permeability, and a coating composition for forming a coating film with a mirror design and a radio wave permeability. BACKGROUND

[0002] In order to improve the commercial power, by coating of an article, a design imparting a pattern, a color, or a combination thereof, which causes a sense of beauty by vision, is implemented. The designs pursued by consumers are various, however, in recent years, by a mirror design having the same texture as a mirror, the recognition of a product is improved. In particular, a mirror design is implemented to vehicle parts of an automobile or the like, a frame of an electronic machine and an information terminal (a smart phone, a mobile phone, or the like), an OA machine, a household electric appliance, an interior finishing material, or the like.

[0003] As a method for imparting a mirror design, (i) electroplating, (ii) evaporation processing (sputtering, ion plating, or the like, a physical thin film forming technique (PVD) or a chemical thin film forming technique (CVD)), and (iii) silver mirror coating are known.

[0004] However, the methods based on (i) electroplating and (iii) silver mirror coating are high in environmental load in terms of wastewater treatment or the like, and require a special device. Further, the number of processes is large and is disadvantageous in terms of manufacturing efficiency or cost, and the quality or durability of the coating film is unstable and is problematic. The method based on (ii) evaporation processing requires a special device for evaporation processing, and the device becomes large and is disadvantageous in terms of introduction cost or the like. Further, these methods have limitations in terms of the material or shape of an article to which a mirror design is imparted or the like.

[0005] Patent Literature 1 describes a decorative member characterized by providing, on a base layer provided on the surface of a base material, a metal film for electromagnetic wave permeation, which is formed by dry processing to have a metallic luster, and then heating the metal film to form fine cracks. The decorative member is formed by dry processing such as sputtering to form a metal film, and thus the manufacturing device is a large device. In addition, with respect to an article having a three-dimensional shape, it is difficult to uniformly provide a metal film by dry processing.

[0006] Patent Literature 2 describes a silver mirror film forming product characterized by, as necessary, performing an activation treatment on a base material on which a base layer is formed, and simultaneously spraying a silver ammonia aqueous solution and a reducing agent solution, which constitute a silver mirror plating solution, on the activated base material by a double spray gun or the like to form a silver mirror film. The silver mirror film forming product requires a special wastewater treatment process for treating the silver mirror plating solution, and in addition, has a problem in terms of the durability of silver.

[0007] Patent Literature 3 describes a coated article characterized by having a laminated coating film that realizes a metallic appearance possessed by a metal plated surface or the like without plating treatment. The coated article is formed by applying a metallic paint containing an opaque flaky pigment and a lustrous pigment that is a metal flake obtained by pulverizing a vapor-deposited metal film, to an object to be coated, and applying a clear top coat on the resulting metallic paint film layer. The coated article can realize a metallic appearance by a simple method, but is not satisfactory in terms of mirror gloss, and does not have radio wave permeability.

[0008] From these aspects, a mirror design plated-style paint that can be formed using existing coating equipment without the need for special equipment is being developed, but is not satisfactory in terms of mirror design.

[0009] Furthermore, it is also known that a mirror-style design (mirror design) paint that realizes a metallic appearance equivalent to plating without the need for special drainage equipment during silver mirror coating, and by the paint and coating. However, the coating film of this paint does not exhibit radio wave permeability, and further, since it requires a drying process at 100°C for 30 minutes, it is difficult to apply to objects to be coated that have low heat resistance.

[0010] In recent years, for mobile phones, electronic machines, and information terminals, frames, automobile parts (metal mesh covers, bumpers, etc.), and the like, mirror designs are pursued while also pursuing radio wave permeability.

[0011] For example, mobile phones, electronic machines, and information terminals have communication antennas and the like inside the frame, and thus need to have radio wave permeability. Furthermore, near the metal mesh cover or bumper of an automobile, there are antennas of various radar devices for distance measurement and the like, and thus radio wave permeability is required. The frequency band region of the radio waves received by these antennas shifts from millimeter waves to microwaves, and the radio wave permeability around the antennas greatly affects the radio wave reception performance.

[0012] Patent Literature

[0013] Patent Literature 1: Japanese Patent Application Publication No. 2018-154878

[0014] Patent Literature 2: Japanese Patent Application Publication No. 2018-177311

[0015] Patent Literature 3: Japanese Patent Application Publication No. 2004-8931 SUMMARY

[0016] The present application provides a coated article having a mirror design and excellent radio wave permeability, a coated article manufacturing method having a mirror design and excellent radio wave permeability, and a coating composition capable of forming a coated article having a mirror design and excellent radio wave permeability.

[0017] The present application has been achieved as a result of intensive studies by the inventors to solve the above problems.

[0018] (1) a coated article having a primer coating layer directly or indirectly provided on a coated object and a coating layer containing vapor-deposited indium thin film fragments directly or indirectly provided on the primer coating layer,

[0019] (2) a coated article manufacturing method having a process of directly or indirectly providing a primer coating layer on a coated object and a process of directly or indirectly providing a coating layer containing vapor-deposited indium thin film fragments on the primer coating layer,

[0020] (3) a coating composition containing a curable primer and a coating containing vapor-deposited indium thin film fragments.

[0021] That is, the present application provides the following coated article, coated article manufacturing method, and coating composition.

[0022] Item 1: A coated article characterized by having:

[0023] (a) a primer coating layer formed from a primer coating material, directly or indirectly provided on a coated object, and

[0024] (b) a metal-containing coating layer having a pigment weight concentration (PWC) of vapor-deposited indium thin film fragments of 70.0% or more, directly or indirectly provided on the primer coating layer,

[0025] and the primer coating material is a two-component curable coating material, an acrylic paint, a melamine-based coating material, or an active energy ray-curable coating material.

[0026] Item 2: The coated article according to item 1, further characterized by having:

[0027] (c) an upper coating layer formed from a two-component curable coating material or an active energy ray-curable coating material, directly or indirectly provided on the metal-containing coating layer.

[0028] Item 3: The coated article according to item 1 or item 2, characterized by satisfying the following important conditions:

[0029] (d) the radio wave permeability of the coated article is 75% or more in the 24 GHz band and the 78 GHz band, and / or,

[0030] (e) the 20° gloss value of the coated article is 150 or more and the 60° gloss value is 170 or more.

[0031] Item 4: A method for manufacturing a coated article, characterized by comprising:

[0032] (i) a step of directly or indirectly providing a base coating film layer based on a base coating material on a coated object, and

[0033] (ii) a step of directly or indirectly providing a metal-containing coating film layer having a pigment weight concentration (PWC) of 70% or more of vapor-deposited indium film fragments on the base coating film layer,

[0034] and the base coating material is a two-liquid type curable coating material, an acrylic paint, a melamine-based coating material, or an active energy ray-curable coating material.

[0035] Item 5: A coating material set, characterized by comprising at least:

[0036] (I) a base coating material, and

[0037] (II) a metal-containing coating material containing vapor-deposited indium film fragments in an amount such that the pigment weight concentration (PWC) in the dried coating film is 70% or more,

[0038]

[0039] and the base coating material is a two-liquid type curable coating material, an acrylic paint, a melamine-based coating material, or an active energy ray-curable coating material.

[0040] According to the present application, a coated article having a mirror design and excellent wave permeability, a coating film formation temperature of which is low, a method for manufacturing a coated article having a mirror design and excellent wave permeability, a coating film formation temperature of which is low, and a coating material set capable of forming a coated article having a mirror design and excellent wave permeability, a coating film formation temperature of which is low, are provided.

[0041] The coated article of the present application does not require large-scale equipment and can be obtained using general coating equipment, and further, since the coating film formation temperature is low, the material or shape of the coated object on which the coating film is formed is not limited. DETAILED DESCRIPTION

[0042] The following describes in detail the mode for carrying out the present application.

[0043] In addition, the present application is not limited to the following embodiments and various modifications implemented within the scope of the gist of the present application are also included.

[0044] ​In the present specification, "parts" means "mass parts" and "%" means "mass %" unless otherwise specified.

[0045] [Coated article]

[0046] The coated article of the present application is a coated article having: (a) a base coat film layer formed of a base coat material provided directly or indirectly on a coated article and (b) a metal-containing coat film layer having a pigment weight concentration (PWC) of 70.0% or more in which an indium thin film fragment is vapor deposited, provided directly or indirectly on the base coat film layer. Here, the base coat material is a two-liquid type curable coating material, an acrylic paint, a melamine-based coating material, or an active energy ray-curable coating material.

[0047] The coated article of the present application can also have (c) an upper coat film layer formed of a two-liquid type curable coating material or an active energy ray-curable coating material, provided directly or indirectly on the metal-containing coat film layer.

[0048] The coated article of the present application preferably satisfies the following important conditions: (d) the radio wave transmittance of the coated article is 75% or more in the 24 GHz band and the 78 GHz band and / or (e) the 20° gloss value of the coated article is 150 or more and the 60° gloss value is 170 or more.

[0049] <Coated article>

[0050] The coated article is not particularly limited, and an article or the like of an arbitrary shape formed of an arbitrary material can be used as the coated article.

[0051] The material of the coated article is not particularly limited. For example, one or more of a metal (one or more of a metal, an alloy, a metal composite, and the like such as iron, aluminum, magnesium, zinc, copper, silver, gold, stainless steel, brass, galvanized steel, and the like), a plastic (one or more of a resin such as an acrylic resin, a polyester resin, a polycarbonate resin, a polyolefin resin, an acrylonitrile-styrene (AS) resin, an acrylonitrile-butadiene-styrene (ABS) resin, an acrylonitrile-styrene-acrylate (ASA) resin, a polyamide resin, a halogenated polyvinylidene chloride resin, a polyphenylene ether resin, a polyoxymethylene resin, a polyurethane resin, an epoxy resin, a phenolic resin, a halogenated ethylene resin, a fatty acid ethylene resin, a silicon resin, a polystyrene resin, an ethylene ether resin, and the like, one or more of a composition containing these, a composite and a laminate composed of one or more of these, and the like), glass, ceramic, wood, paper, a fiber (woven fabric, nonwoven fabric, woven fabric, thread, and the like) can be exemplified. Furthermore, one or more of a composition containing these, a composite and a laminate composed of one or more of these, and the like can also be used.

[0052] The shape of the coated article is not particularly limited. It can be a planar shape or a three-dimensional shape, and can be formed into a plate shape, a film shape, a rod shape, a long strip shape, a three-dimensional shape, for example.

[0053] There is no particular limitation as to the article to be coated and the like. For example, there can be mentioned a frame or a member of various machines such as a mobile phone, a communication device, an information terminal, a game machine, a household electric appliance, a bumper, a metal mesh cover, a vehicle member such as a lighting fixture, a stationery, a toy, a food container, a building material, a structural member for construction, a resin film, a resin molded body, and the like.

[0054] In the present application, it is preferable to coat a plastic frame of various machines such as a mobile phone, a communication device, an information terminal, a game machine, a household electric appliance, a plastic vehicle member such as a bumper or a metal mesh cover, a plastic toy, a building material, a resin film, a resin molded body, and the like.

[0055] <Undercoat Film Layer>

[0056] The undercoat film layer is a film layer provided directly or indirectly on the article to be coated.

[0057] When provided indirectly on the article to be coated, one or more of desired layers such as a primer layer, a chemical conversion treatment layer, an adhesive layer, a colored film layer, a laminated film layer, and the like can be provided between the article to be coated and the undercoat film layer.

[0058] The undercoat film layer can be provided on the entire surface of the article to be coated or on a desired portion of the surface of the article to be coated.

[0059] The undercoat paint used to form the undercoat film layer is not particularly limited as long as the paint has a mirror design and a radio wave permeability. For example, there can be mentioned a two-component curable paint, a one-component curable paint, a non-curable paint, or an active energy ray curable paint. Among these, a two-component curable paint, an acrylic paint, a melamine-based paint, or an active energy ray curable paint is particularly preferable. These undercoat paints can also contain, as necessary, a solvent, a plasticizer, an adhesion-improving agent, a silane coupling agent, a colorant, and the like.

[0060] The thickness (dry film thickness) of the undercoat film layer is not particularly limited. For example, it can be 1.0 μm or more, preferably 5.0 μm or more, and more preferably 10.0 μm or more. For example, it can be set to 30.0 μm or less, preferably 25.0 μm or less, and more preferably 20.0 μm or less. When the thickness is less than 1.0 μm, there is a risk that unevenness will occur on the mirror surface, and in addition, there is a risk that the mirror surface will whiten. When the thickness exceeds 30.0 μm, there is a risk that a particle feeling will occur on the mirror surface, a risk that the mirror surface will whiten, a risk that the surface smoothness will deteriorate and the mirror design will decrease, and a risk that the amount of the undercoat paint used to form the undercoat film layer will increase and the cost will increase.

[0061] (Two-component curable paint)

[0062] As a two-pack type curable coating material, there is no particular limitation as long as it is a coating material that forms a coating film by mixing two packs at the time of coating. For example, a coating material composed of a main agent having a functional group, and a curing agent (crosslinking agent) that can cause a reaction with the functional group of the main agent to cure can be exemplified.

[0063] As the main agent, for example, one or more selected from a compound having a group containing active hydrogen, a compound having an epoxy group, a compound having a carbon-carbon unsaturated double bond, and the like can be exemplified. As the group containing active hydrogen, for example, a hydroxyl group, a carboxyl group, a primary amino group, a secondary amino group, an amide group, and the like can be exemplified.

[0064] As such a main agent, for example, a polyol compound, a polycarboxylic acid compound, an epoxy compound, an alkenyl-containing compound, and the like can be exemplified. These can be used individually or in combination of two or more.

[0065] It is preferable that the one or more polyol compounds be one or more selected from an acrylic polyol, a polyether polyol, a polyester polyol, and a polyurethane polyol, more preferably one or more acrylic polyols.

[0066] Further, it is preferable that the polyester-based resin and / or the acrylic-based resin be one that can react with the melamine compound.

[0067] The weight average molecular weight of the main agent is not particularly limited, and for example, is 300 or more, preferably 500 or more, more preferably 1,000 or more, and for example, is 100,000 or less, preferably 70,000 or less, more preferably 50,000 or less. When the weight average molecular weight is less than 300, there is a concern that the adhesion of the base coating film layer will be poor. When the weight average molecular weight exceeds 100,000, there is a concern that the surface smoothness of the base coating film layer will be poor, and there is a concern that the mirror design will be poor.

[0068] In the present application, a mixture of two or more different in weight average molecular weight can also be used as the main agent.

[0069] The weight average molecular weight can be calculated from a chromatogram measured by gel permeation chromatography, for example, using polystyrene as a standard. As the gel permeation chromatography, for example, "HLC8120GPC" (manufactured by Tosoh Corporation) or the like can be used. As the column, for example, one or more of "TSKgel G-4000HXL", "TSKgel G-3000HXL", "TSKgel G-2500HXL", "TSKgel G-2000HXL" (all manufactured by Tosoh Corporation, trade name), and the like can be used. As the measurement conditions, for example, tetrahydrofuran can be used as the mobile phase, the measurement temperature can be set to 40°C, the flow rate can be set to 1 cc / minute, and the detector can be set to RI.

[0070] When the polyol compound is used as the main agent, the hydroxyl value thereof can be set to 10 mgKOH / g or more, can be preferably set to 30 mgKOH / g or more, can be more preferably set to 50 mgKOH / g or more, can be set to 500 mgKOH / g or less, can be preferably set to 300 mgKOH / g or less, and can be more preferably set to 200 mgKOH / g or less, for example. When the hydroxyl value is less than 50 mgKOH / g, there is a risk that the mirror design property will deteriorate due to a decrease in crosslinking density. When the hydroxyl value exceeds 500 mgKOH / g, there is a risk that the adhesion between the base coating film layer and the coating film layer containing a metal will deteriorate.

[0071] When the polyol compound is used as the main agent, the glass transition temperature thereof can be set to -40°C or more, can be preferably set to 20°C or more, can be set to 100°C or less, and can be preferably set to 80°C or less, for example. By setting the glass transition temperature to -40°C or more, the surface smoothness of the coating film can be imparted. By setting the glass transition temperature to 100°C or less, the necessary hardness of the coating film can be imparted.

[0072] As the curing agent (crosslinking agent), one or more selected from compounds having a group that reacts with the functional group possessed by the main agent can be exemplified, for example. As the group that reacts with the functional group possessed by the main agent, isocyanate groups, amino groups, imino groups, methylol groups, alkyl ether groups, carboxyl groups, hydroxyl groups, and the like can be exemplified, for example.

[0073] As the curing agent (crosslinking agent) of the present application, polyisocyanate compounds, melamine compounds, polyamine compounds, polycarboxylic acid compounds, polyol compounds, and the like can be exemplified, for example. These can be used individually or two or more can be used in combination. One or more selected from one or more of polyisocyanate compounds, melamine compounds, and polyamine compounds is preferred, and one or more of polyisocyanate compounds is more preferred.

[0074] The polyisocyanate compound is a compound having at least two isocyanate groups in one molecule, and aliphatic polyisocyanates, alicyclic polyisocyanates, aromatic aliphatic polyisocyanates, aromatic polyisocyanates, derivatives of these polyisocyanates, and the like can be exemplified, for example.

[0075] The polyisocyanate compound can be used individually or two or more can be used in combination.

[0076] As the aliphatic polyisocyanate, for example, aliphatic diisocyanates such as trimethylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, pentamethylene diisocyanate, 1,2- propylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, 2,4,4- or 2,2,4-trimethylhexamethylene diisocyanate, dimer acid diisocyanate, 2,6-diisocyanatohexanoic acid methyl ester (common name: lysine diisocyanate), 2,6-diisocyanatohexanoic acid 2-isocyanatoethyl ester, 1,6-diisocyanato-3-isocyanatomethylhexane, 1,4,8-triisocyanatooctane, 1,6,11-triisocyanatoundecane, 1,8-diisocyanato-4-isocyanatomethyloctane, 1,3,6-triisocyanatohexane, 2,5,7-trimethyl-1,8-diisocyanato-5-isocyanatomethyloctane, and the like; and aliphatic triisocyanates such as 2,6-diisocyanatohexanoic acid 2-isocyanatoethyl ester, 1,6-diisocyanato-3-isocyanatomethylhexane, 1,4,8-triisocyanatooctane, 1,6,11-triisocyanatoundecane, 1,8-diisocyanato-4-isocyanatomethyloctane, 1,3,6-triisocyanatohexane, 2,5,7-trimethyl-1,8-diisocyanato-5-isocyanatomethyloctane, and the like. These can be used individually or in combination of two or more.

[0077] As the alicyclic polyisocyanate, for example, alicyclic diisocyanates such as 1,3-cyclopentane diisocyanate, 1,3-cyclopentene diisocyanate, 1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate, 3-isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (common name: isophorone diisocyanate), 4-methyl-1,3-cyclohexylene diisocyanate (common name: hydrogenated TDI), 2-methyl-1,3-cyclohexylene diisocyanate, 1,3- or 1,4-bis(isocyanatomethyl)cyclohexane (common name: hydrogenated xylene diisocyanate), or a mixture thereof, methylenebis(4,1-cyclohexanediyl) diisocyanate (common name: hydrogenated MDI), norbornane diisocyanate, and the like; alicyclic triisocyanates such as 1,3,5-triisocyanatocyclohexane, 1,3,5-trimethylisocyanatocyclohexane, 2-(3-isocyanatopropyl)-2,5-di(isocyanatomethyl)-bicyclo(2.2.1)heptane, 2-(3-isocyanatopropyl)-2,6-di(isocyanatomethyl)-bicyclo(2.2.1)heptane, 3-(3-isocyanatopropyl)-2,5-di(isocyanatomethyl)-bicyclo(2.2.1)heptane, 5-(2-isocyanatoethyl)-2-isocyanatomethyl-3-(3-isocyanatopropyl)-bicyclo(2.2.1)heptane, 6-(2-isocyanatoethyl)-2-isocyanatomethyl-3-(3-isocyanatopropyl)-bicyclo(2.2.1)heptane, 5-(2-isocyanatoethyl)-2-isocyanatomethyl-2-(3-isocyanatopropyl)-bicyclo(2.2.1)-heptane, 6-(2-isocyanatoethyl)-2-isocyanatomethyl-2-(3-isocyanatopropyl)-bicyclo(2.2.1)heptane, and the like; and the like. These can be used individually or in combination of two or more.

[0078] As the aromatic aliphatic polyisocyanate, for example, methylenebis (4, 1-phenylene) diisocyanate (common name: MDI), 1, 3- or 1, 4-xylylene diisocyanate or a mixture thereof, ω, ω'-diisocyanato-l, 4-diethylbenzene, 1, 3- or 1, 4-bis (1-isocyanato-l-methylethyl) benzene (common name: tetramethylxylylene diisocyanate) or a mixture thereof, aromatic aliphatic diisocyanates, 1, 3, 5-triisocyanatomethylbenzene, aromatic aliphatic triisocyanates, and the like can be exemplified. These can be used individually or in combination of two or more.

[0079] As the aromatic polyisocyanate, for example, m-phenylene diisocyanate, p-phenylene diisocyanate, 4, 4'-diphenyl diisocyanate, 1, 5-naphthalene diisocyanate, 2, 4-tolylene diisocyanate (common name: 2, 4-TDI) or 2, 6-tolylene diisocyanate (common name: 2, 6-TDI) or a mixture thereof, 4, 4'-toluidine diisocyanate, 4, 4'-diphenyl ether diisocyanate, aromatic diisocyanates, triphenylmethane-4, 4', 4"-triisocyanate, 1, 3, 5-triisocyanatobenzene, 2, 4, 6-triisocyanatotoluene, aromatic triisocyanates, 4, 4'-diphenylmethane-2, 2', 5, 5'-tetraisocyanate, aromatic tetraisocyanates, and the like can be exemplified. These can be used individually or in combination of two or more.

[0080] As the derivative of the polyisocyanate, for example, the dimer, trimer, biuret, allophanate, uretdione, uretonimine, isocyanurate, oxadiazinetrione, polymethylene polyphenyl polyisocyanate (crude MDI, polymeric MDI), crude TDI, and the like of the above polyisocyanate can be exemplified.

[0081] These can be used individually or in combination of two or more.

[0082] In the present application, one or more selected from the group consisting of hexamethylene diisocyanate or a derivative thereof, 4, 4'-methylenebis (cyclohexyl isocyanate) or a derivative thereof, xylylene diisocyanate or a derivative thereof is preferred. Among them, a derivative of hexamethylene diisocyanate is particularly preferred from the viewpoint of adhesiveness, compatibility, and the like.

[0083] As the polyisocyanate compound, a prepolymer formed by reacting a compound having an active hydrogen group such as a hydroxyl group, an amino group, or the like, which is reactive with the isocyanate group in the above polyisocyanate or derivative thereof, under the condition that the isocyanate group is present in excess, can also be used. As the compound reactive with the polyisocyanate, for example, a polyhydric alcohol, a low-molecular-weight polyester-based resin, an amine, water, a resin containing an active hydrogen group (an acrylic polyol, a polyolefin polyol, a polyurethane polyol, a polyether polyol, a polyester polyol), or the like can be exemplified. These can be used individually or in combination of two or more.

[0084] As the polyisocyanate compound, a blocked polyisocyanate compound, which is a compound obtained by blocking the isocyanate group in the polyisocyanate or derivative thereof with a blocking agent, can be used.

[0085] As the end-capping agent, for example, there can be mentioned phenols such as phenol, cresol, xylenol, nitrophenol, ethylphenol, hydroxydiphenyl, butylphenol, isopropylphenol, nonylphenol, octylphenol, methylhydroxybenzoate, and the like; lactams such as ε-caprolactam, δ-valerolactam, γ-butyrolactam, β-propiolactam, and the like; aliphatic alcohols such as methanol, ethanol, propanol, butanol, pentanol, lauryl alcohol, and the like; ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, methoxy methanol, and the like; alcohols such as benzyl alcohol, glycolic acid, methyl glycolate, ethyl glycolate, butyl glycolate, lactic acid, methyl lactate, ethyl lactate, butyl lactate, hydroxymethyl urea, hydroxymethyl melamine, diacetone alcohol, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, and the like; oximes such as formamidoxime, acetamidoxime, propanedione monoxime, methyl ethyl ketoxime, diacetyl monoxime, benzophenone oxime, cyclohexanone oxime, and the like; active methylene compounds such as malonic acid dimethyl ester, malonic acid diethyl ester, acetoacetic acid ethyl ester, acetoacetic acid methyl ester, acetylacetone, and the like; mercaptans such as butyl mercaptan, t-butyl mercaptan, hexyl mercaptan, t-dodecyl mercaptan, 2-mercaptobenzothiazole, thiophenol, methylthiophenol, ethylthiophenol, and the like; acid amides such as acetanilide, methoxyacetanilide, acetyl-m-toluidine, acrylamide, methacrylamide, acetamide, stearamide, benzamide, and the like; imides such as succinimide, phthalimide, maleimide, and the like; amines such as diphenylamine, phenylnaphthylamine, dimethylaniline, N-phenyldimethylaniline, carbazole, aniline, naphthylamine, butylamine, dibutylamine, butylaniline, and the like; imidazoles such as imidazole, 2-ethylimidazole, and the like; ureas such as urea, thiourea, ethylene urea, ethylene thiourea, diphenyl urea, and the like; carbamates such as N-phenyl phenyl carbamate; imines such as ethylene imine, propylene imine, and the like; sulfites such as sodium bisulfite, potassium bisulfite, and the like; azole compounds, and the like. These can be used individually or in combination of two or more. As the azole compound, there can be mentioned pyrazoles or pyrazole derivatives such as pyrazole, 3,5-dimethylpyrazole, 3-methylpyrazole, 4-benzyl-3,5-dimethylpyrazole, 4-nitro-3,5-dimethylpyrazole, 4-bromo-3,5-dimethylpyrazole, 3-methyl-5-phenylpyrazole, and the like; imidazoles or imidazole derivatives such as imidazole, benzimidazole, 2-methylimidazole, 2-ethylimidazole, 2-phenylimidazole, and the like; imidazoline derivatives such as 2-methylimidazoline, 2-phenylimidazoline, and the like. These can be used individually or in combination of two or more.

[0086] For blocking based on the reaction of a polyisocyanate or a derivative thereof with a blocking agent, a solvent can be added as needed for implementation. As a solvent used in the blocking reaction, a substance that is not reactive with respect to isocyanate groups is preferable, and examples include ketones such as acetone and methyl ethyl ketone, esters such as ethyl acetate, and nitrogen-containing solvents such as N-methyl-2-pyrrolidone (NMP). These can be used individually or in combination with two or more.

[0087] As the combination of the main agent and the curing agent in the two-liquid type curable coating, for example, acrylic polyol compounds / polyisocyanate compounds, polyester polyols / polyisocyanate compounds, polyether polyols / polyisocyanate compounds, polyester-based resins / melamine compounds, acrylic resins / melamine compounds, and epoxy-based resins / polyamine compounds can be cited. Among these, acrylic polyol compounds / polyisocyanate compounds, polyester polyols / polyisocyanate compounds, polyester-based resins / melamine compounds, and acrylic resins / melamine compounds are preferable.

[0088] (acrylic paint)

[0089] As the acrylic paint, an acrylic resin composed of a (meth)acrylate-based copolymer, a coating in which an acrylic resin is modified with other components. As the other components for modification, for example, various cellulose-based resins, vinyl-based resins, polyurethane-based resins, and the like can be cited. These can be used individually or in combination with two or more.

[0090] In the present application, as the acrylic paint, acrylic resin varnish, acrylic resin enamel, NC (nitrocellulose)-modified acrylic paint, CAB (cellulose acetate butyrate)-modified acrylic paint, vinyl-based resin-modified acrylic paint, and the like can be cited. These can be used individually or in combination with two or more. Particularly preferable are NC (nitrocellulose)-modified acrylic paint or CAB (cellulose acetate butyrate)-modified acrylic paint, and the like, which contain an acrylic resin and a cellulose-based compound. As the cellulose-based compound, for example, one or more of nitrocellulose, cellulose acetate butyrate, and the like can be cited. The acrylic paint can also contain, as needed, a solvent, a plasticizer, a pigment, and the like.

[0091] (melamine-based paint)

[0092] The melamine-based paint is a paint containing a melamine-based resin, a polyester-based resin, or an acrylic resin.

[0093] As the melamine-based resin, a melamine resin having one or more melamine nuclei obtained by condensing melamine with formaldehyde can be exemplified. In addition, an alkyl etherified melamine resin obtained by reacting an alcohol compound such as methanol, ethanol, propanol, butanol, isobutanol, or the like with a melamine resin can also be used.

[0094] The melamine-based resin can also use a commercially available product. For example, a product with the trade name "CYMEL" series (e.g., CYMEL 202, CYMEL 204, CYMEL 211, CYMEL 232, CYMEL 235, CYMEL 236, CYMEL 238, CYMEL 250, CYMEL 251, CYMEL 254, CYMEL 266, CYMEL 267, CYMEL 285, etc.) manufactured by Allnex, a product with the trade name "U-van" series (U-van 20N60, U-van 20SE, etc.) manufactured by Mitsui Chemicals, and the like can be exemplified. These can be used individually or in combination of two or more.

[0095] The content of the melamine-based resin in the melamine-based coating is 10 to 60 parts by mass, and preferably 20 to 50 parts by mass, relative to 100 parts by mass of the total amount of the resin solid components.

[0096] (Living energy ray-curable coating)

[0097] The living energy ray-curable coating is a coating containing a resin which undergoes a cross-linking reaction or the like and is cured by irradiation of a living energy ray such as ultraviolet rays (UV), visible rays, infrared rays, electron beams (EB), or the like. As the living energy ray-curable coating, for example, a coating containing one or more living energy ray-curable compounds and a polymerization initiator, and, as necessary, a colorant or the like can be exemplified. In the present application, an ultraviolet ray-curable coating or an electron beam-curable coating is preferred.

[0098] As the living energy ray-curable compound, for example, one or more compounds having an ethylenic unsaturated double bond can be exemplified. As the living energy ray-curable compound, for example, one or more selected from the group consisting of (meth)acrylate compounds, (meth)acrylate oligomers, ultraviolet ray-curable resins, electron beam-curable resins, and the like can be exemplified.

[0099] As the active energy ray-curable coating, a substance containing a (meth)acrylic compound having 2 or more (meth)acryloyl groups in one molecule, which forms a three-dimensional network structure by crosslinking and curing, is preferable. As the (meth)acrylic compound, for example, a diacrylate compound, a triacrylate compound, a tetraacrylate compound, a hexaacrylate compound, a urethane (meth)acrylate, a polyester (meth)acrylate, an epoxy (meth)acrylate, a melamine (meth)acrylate, and the like can be exemplified. These can be used alone or in combination of two or more.

[0100] As the polymerization initiator contained in the active energy ray-curable coating, a compound which generates a radical upon irradiation of an active energy ray such as ultraviolet rays (UV), visible rays, infrared rays, electron beams (EB), and the like can be exemplified.

[0101] For example, an acylphosphine oxide-based polymerization initiator, an α-hydroxyalkylphenone-based polymerization initiator, an acetophenone-based polymerization initiator, a benzoylformate-based polymerization initiator, a thioxanthone-based polymerization initiator, an oxime ester-based polymerization initiator, a hydroxybenzoyl-based polymerization initiator, a benzophenone-based polymerization initiator, an α-aminoalkylphenone-based polymerization initiator, a benzoin-based polymerization initiator, a benzyl acetal-based polymerization initiator, an acid ester-based polymerization initiator, a titanocene-based polymerization initiator, a quinone-based polymerization initiator, an organic peroxide-based polymerization initiator, an azo-based polymerization initiator, and the like can be exemplified. These can be used alone or in combination of two or more.

[0102] As specific examples thereof, for example, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, 2,4,6-trimethylbenzoylphenylethoxyphosphine oxide, 1-hydroxycyclohexyl phenyl ketone, 2-hydroxy-2-methyl-l-phenylpropan-l-one, 2,2-dimethoxy-l,2-diphenylethane-l-one, l-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-l-propane-l-one, 2-hydroxy-l-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propane-l-one, oligomeric (2-hydroxy-2-methyl-l-(4-(l-methylethenyl)phenyl)propanone), l-(4-isopropylphenyl)-2-hydroxy-2-methylpropane-l-one, acetophenone, 3-methylacetophenone, diethoxyacetophenone, benzoin, benzoin benzoate, α-acyloxime ester, isobomyl phenyl ketone, phenyl glyoxylic acid methyl ester, benzophenone, 4-phenylbenzophenone, 4-chlorobenzophenone, 4,4'-diaminobenzophenone, Michler's ketone, benzyl dimethyl acetal, 1,2-octanedione, benzoin alkyl ethers, 2-benzyl-2-dimethylamino-l-(4-morpholinyl-phenyl)-butan-l-one, 2-methyl-l-[4-(methylthio)phenyl]-2-morpholinopropan-l-one, l-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-3-(cyclopentyl)propan-l-one (O-acetyloxime), methylbenzoylformate, 4-benzoyl-4'-methyldiphenyl sulfide, ethyl anthraquinone, phenanthrenequinone, camphorquinone, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, thioxanthone, 2-chlorothioxanthone, isopropyl thioxanthone, l-chloro-4-propylthioxanthone, 3-[3,4-dimethyl-9-oxo-9H-thioxanthen-2-yl-oxy]-2-hydroxypropyl-N,N,N-trimethylammonium chloride, fluorothioxanthone, and the like can be enumerated. These can be used individually or in combination of two or more.

[0103] As the irradiation method of active energy rays at the time of curing the active energy ray-curable coating material, for example, the irradiation of ultraviolet rays having a wavelength of 100 to 400 nm, preferably 200 to 400 nm, emitted from an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc lamp, a metal halide lamp, a UV-LED, or the like, or the irradiation of electron rays having a wavelength of 100 nm or less emitted from a scanning type or a curtain type electron ray accelerator can be cited.

[0104] < Metal-containing coating film layer >

[0105] The metal-containing coating film layer is a coating film layer having a pigment weight concentration (PWC) of 70.0% or more of a vapor-deposited indium film fragment, which is disposed directly or indirectly on the base coating film layer.

[0106] When the metal-containing coating film layer is indirectly provided on the undercoat film layer, one or more of the desired layers such as a primer layer, a chemical conversion treatment layer, an adhesive layer, a colored coating film layer, a laminated film layer, and the like can be provided between the undercoat film layer and the metal-containing coating film layer.

[0107] The metal-containing coating film layer can be provided on the entire surface of the undercoat film layer or on a desired portion of the undercoat film layer.

[0108] The thickness of the metal-containing coating film layer is not particularly limited and is preferably thin. For example, the thickness can be 3.0 μm or less, preferably 2.0 μm or less, more preferably 1.0 μm or less, and for example, the thickness can be 0.01 μm or more, can preferably be 0.05 μm or more, and can more preferably be 0.1 μm or more. When the thickness is 3.0 μm or more, there is a risk that unevenness or a particle feeling will occur on the mirror surface, and in addition, there is a risk that the mirror surface will whiten and become cloudy. When the thickness is less than 0.01 μm, there is a risk that unevenness or a particle feeling will occur on the mirror surface, there is a risk that the mirror surface will become cloudy, there is a risk that the acquisition of the coating film forming material will become difficult, and further, a highly skilled coating technique will be required, which is disadvantageous in terms of cost.

[0109] The pigment weight concentration (PWC) of the evaporation indium thin film fragments in the metal-containing coating film layer is 70.0% or more. The PWC is preferably 73.0% or more, more preferably 81.0% or more, and further preferably 90.0% or more. The upper limit of the PWC is 100% or less. Depending on the case, the PWC can be less than 100%, for example, 99.9% or less or, for example, 99.5% or less.

[0110] The metal-containing coating film layer is formed from a coating material containing evaporation indium thin film fragments.

[0111] (Coating material containing evaporation indium thin film fragments)

[0112] The coating material containing evaporation indium thin film fragments contains evaporation indium thin film fragments and a solvent, and further, as needed, a small amount of a binder such as a resin can also be contained.

[0113] The content of the evaporation indium thin film fragments in the coating material containing evaporation indium thin film fragments is an amount that achieves a pigment weight concentration (PWC) of the evaporation indium thin film fragments in the metal-containing coating film layer of 70.0% or more. The PWC is preferably 73.0% or more, more preferably 81.0% or more, and further preferably 90.0% or more.

[0114] The evaporation indium thin film fragments are composed of indium having a purity of 95% or more and can also contain a small amount of impurities.

[0115] The vapor-deposited indium thin film fragments are flaky particles, and are sometimes referred to as scale-like particles, plate-like particles, and the like. The vapor-deposited indium thin film fragments are particles having a substantially flat face, and a thickness in a direction perpendicular to the substantially flat face is substantially uniform. The thickness is very thin, and the length of the substantially flat face is a very long shape. The length of the substantially flat face is the diameter of a circle having a projection area identical to the projection area of the vapor-deposited indium thin film fragment.

[0116] The shape of the substantially flat face is not particularly limited, and can be appropriately selected according to the purpose. For example, a substantially rectangular shape, a substantially square shape, a substantially circular shape, a substantially elliptical shape, a substantially triangular shape, a substantially quadrangular shape, a substantially pentagonal shape, a substantially hexagonal shape, a substantially heptagonal shape, a substantially octagonal shape, and the like, a random irregular shape, and the like can be mentioned. Among these, a substantially circular shape is preferred.

[0117] The vapor-deposited indium thin film fragments can be one layer (single layer) or two or more layers stacked to become primary particles. In addition, the primary particles of the vapor-deposited indium thin film fragments can also be aggregated to form secondary particles.

[0118] The average thickness of the vapor-deposited indium thin film fragments is, for example, 0.100 μm or less, preferably 0.075 μm or less, and more preferably 0.060 μm or less, and can be set to, for example, 0.001 μm or more, and can be preferably set to 0.010 μm or more, and can be more preferably set to 0.030 μm or more.

[0119] The cumulative 50% volume particle diameter D50 of the vapor-deposited indium thin film fragments is, for example, 1.00 μm or less, and preferably 0.70 μm or less, and can be set to, for example, 0.01 μm or more, and can be preferably set to 0.05 μm or more.

[0120] In the case of the vapor-deposited indium thin film fragments of the present application, in a volume-based standard particle size distribution showing the relationship between the particle diameter and the volume proportion of the vapor-deposited indium thin film fragments having that particle diameter, a first peak and a second peak larger than the first peak are present, and the volume V1 of the vapor-deposited indium thin film fragments of the first peak and the volume V2 of the vapor-deposited indium thin film fragments of the second peak satisfy the condition (V1 / V2) x 100 ≧ 25%,

[0121] The particle diameter PI of the vapor-deposited indium thin film fragments of the first peak and the particle diameter P2 of the indium particles of the second peak satisfy the condition 6.0 ≦ P2 / PI ≦ 12, and preferably satisfy the condition 6.0 ≦ P2 / PI ≦ 10,

[0122] It is preferred that the cumulative 50% volume particle diameter D50 of the vapor-deposited indium thin film fragments satisfy the condition 0.70 μm or less.

[0123] It is further preferred that the particle diameter P2 of the vapor-deposited indium thin film fragments of the second peak satisfy the condition 0.75 μm or less.

[0124] The indium thin film fragments are vapor-deposited, for example, by forming an indium-containing metal layer on a substrate having a peeling property by vacuum vapor deposition and peeling the metal layer.

[0125] As the substrate having a peeling property, a material having a smooth surface can be exemplified, and a substrate formed of a material having a peeling property or a substrate having a peeling layer formed on the surface can be exemplified.

[0126] As the peeling layer, various organic substances that are soluble can be used in the peeling process. Furthermore, as long as the organic substance material constituting the peeling layer can be appropriately selected, the organic substance adhering and remaining on the peeling surface of the island structure film can function as a protective layer of the indium thin film fragments, and thus is preferable.

[0127] The so-called protective layer has a function of inhibiting the aggregation, oxidation, and elution into a solvent of the indium thin film fragments. In particular, by utilizing the organic substance for the peeling layer as the protective layer, it is not necessary to additionally provide a surface treatment process, and thus is preferable.

[0128] As the organic substance constituting the peeling layer that can be utilized as the protective layer, for example, cellulose-based resins such as cellulose acetate butyrate (CAB), polyvinyl alcohol, polyvinyl acetal, polyethylene glycol, polyacrylic acid, polyacrylamide, polyvinyl acetal, acrylic acid copolymers, modified nylon-based resins, polyvinylpyrrolidone, polyurethane-based resins, polyester-based resins, polyether-based resins, alkyd-based resins, and the like can be exemplified. These can be used individually or in combination of two or more. Among them, from the viewpoint of the function as the protective layer, cellulose-based resins such as cellulose acetate butyrate (CAB) are preferable.

[0129] The method of forming the peeling layer is not particularly limited, and can be appropriately selected according to the purpose, and for example, inkjet method, blade coating method, etching coating method, etching flexographic coating method, bar coating method, roll coating method, knife coating method, air knife coating method, doctor blade coating method, U doctor blade coating method, AKKU coating method, smooth coating method, micro-etching coating method, reverse roll coating method, four-roll coating method, five-roll coating method, dip coating method, curtain coating method, inclined plate coating method, die coating method, and the like can be exemplified. These can be used individually or in combination of two or more.

[0130] The vacuum vapor deposition process is a process of vacuum vapor-depositing an indium-containing metal layer on the peeling layer in such a manner that the average vapor deposition thickness reaches 60 nm or less.

[0131] The average vapor deposition thickness of the indium-containing metal layer is 60 nm or less, preferably 55 nm or less, more preferably 50 nm or less, and further preferably 45 nm or less. In addition, the average vapor deposition thickness of the indium-containing metal layer is the same as the average thickness of the indium thin film fragments.

[0132] When the average deposition thickness of the metal layer is 60 nm or less, the surface roughness Ra of the coating film decreases, the gloss value, which is an index of expressing the metallic design property, increases, and the coating film has the advantage of being able to express an excellent metallic design property.

[0133] The average deposition thickness is, for example, measured as an average of the thickness of the metal layer at 5 to 10 points by performing cross-sectional observation of the metal layer using a scanning electron microscope (SEM).

[0134] The metal layer is preferably an island structure film. The island structure film can be formed, for example, by various methods such as vacuum deposition, sputtering, and plating. Among them, vacuum deposition is preferred.

[0135] Vacuum deposition is more preferred than plating in terms of film formation on a resin substrate, non-generation of waste liquid, and the like, and is more preferred than sputtering in terms of improvement in vacuum degree, large film formation speed (deposition rate), and the like.

[0136] The deposition rate in vacuum deposition is preferably 10 nm / sec or more, and more preferably 10 nm / sec or more and 80 nm / sec or less.

[0137] When a thin film of indium is formed on the peeling layer, each indium atom flying from the deposition source reaches the substrate surface, loses energy by interaction with the substrate, and is adsorbed on the substrate, and diffuses on the substrate surface. The indium atoms collide with each other, combine, and form three-dimensional nuclei. When the number of atoms of the formed three-dimensional nuclei exceeds a certain critical value by capturing surface-diffused atoms on the substrate, the three-dimensional nuclei grow into an island shape by merging with adjacent three-dimensional nuclei to form an island structure film. Such an island structure film maintains the film shape on the substrate, but is split into individual islands to become a deposition indium thin film fragment when peeled from the substrate.

[0138] The shape of the finally obtained deposition indium thin film fragment or the volume ratio (V1 / V2) x 100 of the ultrafine particles to the fine particles in the cumulative 50% volume particle diameter can be controlled by changing the average film thickness (hereinafter sometimes referred to simply as "film thickness") of the island structure film. The average film thickness of the island structure film can be measured using interference of the film during film formation, and thus by previously obtaining the relationship with the shape or size of the deposition indium thin film fragment, a deposition indium thin film fragment having a desired shape and size can be easily obtained. In addition, as operation factors that affect the shape of the deposition indium thin film fragment or the volume ratio of the ultrafine particles to the fine particles in the cumulative 50% volume particle diameter, the film formation method, the energy (kinetic energy and temperature, etc.) of indium flying toward the substrate, the surface free energy, the material, and the temperature of the peeling layer, the cooling method and the temperature of the substrate, the film formation speed, and the like can be listed.

[0139] The peeling step is a step of peeling the metal layer by dissolving the peeling layer.

[0140] As the solvent which can dissolve the peeling layer, there is no particular limitation as long as it is a solvent which can dissolve the peeling layer, and it can be appropriately selected according to the purpose, and as the solvent for the film formation of the metal-containing film, a substance which can be directly used is preferred.

[0141] As the solvent which can dissolve the peeling layer, for example, alcohols such as methanol, ethanol, propanol, isopropanol, butanol, octanol, dodecanol, ethylene glycol, propylene glycol, ethers such as tetrahydrofuran, ketones such as acetone, methyl ethyl ketone, acetylacetone, esters such as methyl acetate, ethyl acetate, butyl acetate, phenyl acetate, ethyl cellosolve, butyl cellosolve, ethyl carbitol, butyl carbitol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monohexyl ether, ethylene glycol monophenyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, phenols such as phenol, cresol, aliphatic hydrocarbons or aromatic hydrocarbons such as pentane, hexane, heptane, octane, dodecane, tridecane, tetradecane, pentadecane, hexadecane, octadecane, octadecene, benzene, toluene, xylene, trimesic acid, nitrobenzene, aniline, methoxybenzene, halogenated aliphatic hydrocarbons or halogenated aromatic hydrocarbons such as dichloromethane, chloroform, trichloroethane, chlorobenzene, dichlorobenzene, sulfur-containing compounds such as dimethyl sulfoxide, nitrogen-containing compounds such as dimethylformamide, dimethylacetamide, acetonitrile, propionitrile, benzonitrile, and the like can be exemplified. These can be used alone or in combination of two or more.

[0142] The evaporation indium thin film fragment of the present application can have an organic layer on at least a part of its surface.

[0143] The surface roughness Ra of the metal-containing coating film layer is not particularly limited, and is, for example, 30 nm or less, preferably 25 nm or less, and more preferably 15 nm or less.

[0144] When the surface roughness Ra is 30 nm or less, the gloss value, which is an index of the mirror design property, can be improved, and the mirror design property can be exhibited excellently.

[0145] The surface roughness Ra can be measured, for example, using a scanning probe microscope (AFM) as the arithmetic average surface roughness Ra in a range of 30 μm x 30 μm.

[0146] <Wave transmittance and / or gloss value>

[0147] The coating of the present invention preferably meets the important condition that the radio wave transmittance is 75% or more in both the 24GHz and 78GHz bands.

[0148] Furthermore, the coated object of the present invention preferably meets the important conditions of a gloss value of 150 or higher at 20° and a gloss value of 170 or higher at 60°. This results in a more refined mirror finish.

[0149] Furthermore, the coating of the present invention preferably satisfies the important conditions that the radio wave transmittance in both the 24GHz and 78GHz bands is 75% or more, and the gloss value at 20° is 700 or more and the gloss value at 60° is 300 or more.

[0150] (Radio wave transmittance)

[0151] The radio wave transmittance of the coated material in both the 24GHz and 78GHz bands is preferably 75% or more. More preferably, it is 85% or more, and even more preferably, it is 90% or more.

[0152] When the radio wave transmittance of the coated object is above 75% in both the 24GHz and 78GHz bands, the impact on radio wave transmission and reception is small, even if the coated object is the frame of a mobile phone, electronic device, information terminal or other communication device, or the metal mesh cover or bumper of a car. This can reduce erroneous operation or failure to operate.

[0153] Here, the radio wave transmittance is determined by the method described in the embodiments.

[0154] (Gloss value)

[0155] The 20° and 60° gloss values ​​of the coated object are, for example, measured using a gloss meter with the incident angle of light as 20° and 60° according to the parallel light method of JIS Z 8741 "Specular gloss - Method for determination".

[0156] The gloss value at 20° (gloss value at an incident angle of 20°) of the coated object is preferably 150 or higher, more preferably 300 or higher, and even more preferably 500 or higher. In particular, when the gloss value at 20° is 700 or higher, the mirror finish is high, and an excellent mirror design can be made.

[0157] Here, the gloss value at an incident angle of 20° represents a reflection intensity similar to that of the orthographic component.

[0158] The gloss value at 60° (gloss value at an incident angle of 60°) of the coated object is preferably 170 or higher, more preferably 250 or higher, and even more preferably 300 or higher. In particular, when the gloss value at 60° is 350 or higher, the mirror finish is high, and an excellent mirror design can be made.

[0159] A gloss value at an incident angle of 60° indicates a reflectance intensity similar to that of the diffuse component.

[0160] The 85° gloss value of the coated article (gloss value at an incident angle of 85° of light) is not particularly limited in the present application. It is preferably 90 or greater, more preferably 93 or greater, and further preferably 95 or greater. In particular, when the 85° gloss value is 100 or greater, the specular property is high, and an excellent mirror design can be produced. The 85° gloss value can be measured by the same method as the 20° gloss value.

[0161] The gloss value of the coated article can be easily adjusted by adjusting the shape of the vapor-deposited indium film fragments, etc. (particle diameter, aspect ratio, thickness, surface roughness, etc.) contained in the coating film layer containing the vapor-deposited indium film fragments. Furthermore, it can also be easily adjusted by adjusting the surface roughness of the base coating film layer.

[0162] (upper coating film layer)

[0163] The coated article of the present application can have an upper coating film layer provided directly or indirectly on the metal-containing coating film layer, as needed.

[0164] The upper coating material used to form the upper coating film layer can be exemplified by a two-component curable coating material, a one-component curable coating material, a non-curable coating material, or an active energy ray-curable coating material. Among these, it can be formed of a curable coating material such as a two-component curable coating material, a one-component curable coating material, or an active energy ray-curable coating material, for example.

[0165] The two-component curable coating material, the one-component curable coating material, or the active energy ray-curable coating material used to form the upper coating film layer can use the same components as those described in the two-component curable coating material, the one-component curable coating material, or the active energy ray-curable coating material used to form the base coating film layer.

[0166] In addition, the upper coating film layer is a colorless transparent clear coating material, or is formed of a colored transparent colored clear coating material. Further, these coating materials can be formed of coating materials to which a resin bead, a ground material such as silica, a metallic pigment, a luster material such as a pearl pigment, or the like is added.

[0167] [Method for producing a coated article]

[0168] The method for producing a coated article of the present application is a method for producing a coated article having (i) a step of providing a base coating film layer based on a base coating material directly or indirectly on a coated object and (ii) a step of providing a metal-containing coating film layer having a pigment weight concentration (PWC) of 70% or greater directly or indirectly on the base coating film layer,

[0169] and the base coating material is a two-component curable coating material, an acrylic paint, a melamine-based coating material, or an active energy ray-curable coating material.

[0170] The kind, material, shape, etc. of the coated object in the method for producing the coated object of the present application are not particularly limited. For example, the coated object described in the coated object of the present application can be exemplified.

[0171] The primer coating in the method for producing the coated object of the present application is not particularly limited as long as it is a two-liquid type curable coating, an acrylic paint, a melamine-based coating, or a active energy ray-curable coating. As such a coating, for example, the primer coating described in the coated object of the present application can be exemplified.

[0172] The metal-containing coating in the method for producing the coated object of the present application is not particularly limited as long as it is a metal-containing coating containing an evaporation indium thin film fragment in an amount such that the pigment weight concentration (PWC) in the dried coating film is 70% or more. As the metal-containing coating, for example, the coating described in the coated object of the present application, which forms a metal-containing coating film layer having a pigment weight concentration (PWC) of an evaporation indium thin film fragment of 70.0% or more, can be exemplified.

[0173] The method for forming the primer coating film layer and the metal-containing coating film layer is not particularly limited as long as it is a method in which a coating film of a coating is provided on an object, a substrate, or the like, according to the shape or use of the object, the substrate, or the like. For example, air spraying, vacuum spraying, electrostatic, rotary atomization, brush, roller, hand gun, universal gun, dipping, roll coating, curtain flow coating, roll curtain coating, die coating, air knife coating, blade coating, spin coating, reverse coating, gravure coating, wire bar coating, inkjet, gravure printing, screen printing, and offset printing can be exemplified. These can be used individually or in combination of two or more. One or more selected from air spraying, vacuum spraying, electrostatic, rotary atomization, brush, hand gun, universal gun, and inkjet are preferably exemplified.

[0174] When the coating film formation surface is contaminated with a contaminant such as oil when the primer coating film layer and / or the metal-containing coating film layer is formed, degreasing and cleaning with alcohol or the like are preferably performed. In addition, in order to improve adhesion or corrosion resistance, surface treatment such as roughening treatment, plasma treatment, flame treatment, primer treatment, or the like can be performed on the coating film formation surface.

[0175] When the primer coating film layer and / or the metal-containing coating film layer is formed, after the coating film is formed by applying the corresponding coating, the coating film can be dried to form the coated object by a method such as normal temperature drying or forced drying. When normal temperature drying is performed, standing at normal temperature (for example, 10 to 40°C) is sufficient. When forced drying is performed, drying can be performed using a hair dryer or the like, or baking drying can be performed by placing in a heating furnace or the like at a temperature higher than normal temperature, for example, 50°C or more, for 1 minute or more.

[0176] When the base coat forming the base coat film layer is a two-liquid type curable coating material, it can also be cured by heating as needed. From the aspect of finish, it can also be left (rested) at room temperature before drying or curing.

[0177] When the base coat forming the base coat film layer is a radiation curable coating material, the coating film is cured by irradiating active energy rays. As the active energy rays used at the time of curing, the active energy rays used at the time of curing of the coating material, i.e., the base coat, used when forming the coated article of the present application can be cited.

[0178] As the active energy ray source, a mercury lamp, a metal halide lamp, a xenon lamp, an excimer laser, a dye laser, an ultraviolet ray source such as a UV-LED, an electron beam accelerator, and the like can be cited. These can be used individually or in combination of two or more.

[0179] The irradiation energy (cumulative light amount) of the active energy rays is not particularly limited. For example, it can be 10 mJ / cm 2 Preferably, it is 100 mJ / cm 2 More preferably, it is 200 mJ / cm 2 Further preferably, it is 500 mJ / cm 2 For example, it can be set to 2,500 mJ / cm 2 Preferably, it is set to 2,000 mJ / cm 2 More preferably, it is set to 1,700 mJ / cm 2 Further preferably, it is set to 1,500 mJ / cm 2 Further.

[0180] From the aspect of finish, it can also be left (rested) at room temperature before drying or curing.

[0181] At the time of coating film formation, it can be set by one coating, or it can be set by two or more coatings. When two or more coatings are performed, a drying step can be provided in the middle, or it can be performed without providing a drying step in the middle in a wet-on-wet manner, or these can be combined.

[0182] As the coating film forming method in the present application, for example, the following methods can be used: (i) 3-layer 3-heating method of forming a base coating film layer, a metal-containing coating film layer, and an upper coating film layer respectively and sequentially drying and curing, (ii) 2-layer 2-heating method of forming a base coating film layer and a metal-containing coating film layer respectively and sequentially drying and curing, (iii) 3-layer 1-heating method of sequentially forming a base coating film layer, a metal-containing coating film layer, and an upper coating film layer and then performing 1-time drying and curing treatment to form all the coating film layers, (iv) 3-layer 2-heating method of forming a base coating film layer and a metal-containing coating film layer, or a metal-containing layer and an upper coating film layer, by 1-time drying and curing treatment among a base coating film layer, a metal-containing coating film layer, and an upper coating film layer, (v) 2-layer 1-heating method of forming a base coating film layer and a metal-containing coating film layer respectively and then performing 1-time drying and curing treatment to form all the coating film layers, and the like.

[0183] In the production method of the coated article of the present application, the thickness (dry film thickness) of the base coating film layer and the metal-containing coating film layer is not particularly limited and can be appropriately adjusted depending on the use or the like. For example, the dry film thickness of the base coating film layer and the metal-containing coating film layer described in the coated article of the present application can be made.

[0184] [Coating material group]

[0185] The coating material group of the present application is composed of at least (I) a base coating material and (II) a metal-containing coating material containing an evaporation-in process indium thin film fragment in an amount such that the pigment weight concentration (PWC) in a dried coating film is 70% or more, and the base coating material is a two-liquid type curable coating material, an acrylic paint, a melamine-based coating material, or an active energy ray curable coating material.

[0186] The coating material group of the present application is characterized by having a base coating film layer formed of a base coating material and disposed directly or indirectly on a coated article, and a metal-containing coating film layer disposed directly or indirectly on the base coating film layer, and is not particularly limited as to the form or the like as long as at least a base coating material and a metal-containing coating material are combined.

[0187] In the coating material group of the present application, the kind, material, shape, or the like of the coated article as the object of coating is not particularly limited. For example, the coated article described in the coated article of the present application can be exemplified.

[0188] In the coating material group of the present application, the base coating material is not particularly limited as long as it is a two-liquid type curable coating material, an acrylic paint, a melamine-based coating material, or an active energy ray curable coating material. As such a coating material, for example, the base coating material described in the coated article of the present application can be exemplified.

[0189] In the paint set of the present application, the metal-containing paint is not particularly limited as long as it contains the evaporation-included indium thin film fragments in an amount of 70% or more in terms of pigment weight concentration (PWC) in a dried paint film. As the metal-containing paint, for example, a paint for forming a metal-containing paint film layer having a pigment weight concentration (PWC) of 70.0% or more of evaporation-included indium thin film fragments described in the coated article of the present application can be cited.

[0190] The coating method of each paint constituting the paint set of the present application is not particularly limited. For example, the coating method described in the production method of the coated article of the present application can be cited.

[0191] The paint set of the present application can further contain one or more selected from an upper layer paint, a thinner, a colored paint, and the like, as needed.

[0192] As the upper layer paint, for example, an upper layer paint which is a two-liquid type curable paint or a radiation curable paint described in the coated article of the present application can be cited.

[0193] As the thinner, a substance which can reduce the viscosity by mixing with the base layer paint, the metal-containing paint, the upper layer paint, and the like, and performing dilution can be cited, and the substance is not particularly limited.

[0194] As the colored paint, for example, a substance which can impart a colored design to the coated article can be cited, and the substance is not particularly limited. In addition, the colored paint can be a paint for forming a concealing layer.

[0195] The paint set of the present application can be preferably used in the formation of the coated article of the present application.

[0196] Example

[0197] Hereinafter, the present application will be further described in detail by production examples, examples, and comparative examples, but the present application is not limited thereto. When not particularly described, "parts" means "mass parts", and "%" means "mass %".

[0198] [Preparation of base layer paint]

[0199] < Base layer paint B1 >

[0200] A main agent X1 of a two-liquid curable paint was prepared so as to contain each component in the following proportions: 30.0 parts of an acrylic resin having a molecular weight of 21,000, 5.5 parts of an acrylic resin having a molecular weight of 14,000, 2.5 parts of an acrylic resin having a molecular weight of 26,000, 0.01 parts of a curing catalyst, and 61.9 parts of a mixed solvent. The mixed solvent contained an ester-based solvent and a ketone-based solvent.

[0201] A curing agent Y1 of a two-liquid curable paint was prepared so as to contain each component in the following proportions: 54.0 parts of a hexamethylene diisocyanate prepolymer and 46.0 parts of an ester-based solvent.

[0202] A diluent Zl was prepared so as to contain each component in the following proportions: 60.0 parts of a ketone solvent and 60.0 parts of an ester solvent.

[0203] A base coat B l was prepared by mixing 100 parts of the base Xl, 12 parts of the curing agent Yl and 120 parts of the diluent Zl. The ratio of hydroxyl groups to isocyanate groups, OH / NCO, was 1.2.

[0204] < Base coat B2 >

[0205] The same base Xl and diluent Zl as in the base coat Bl were used as the base and diluent.

[0206] A curing agent Y2 for a two-pack curing type paint was prepared so as to contain each component in the following proportions: 58.0 parts of a hexamethylene diisocyanate prepolymer and 42.0 parts of an ester solvent.

[0207] A base coat B2 was prepared by mixing 100 parts of the base Xl, 12 parts of the curing agent Y2 and 120 parts of the diluent Zl. The ratio of hydroxyl groups to isocyanate groups, OH / NCO, was 1.2.

[0208] < Base coat B3 >

[0209] The same base Xl and diluent Zl as in the base coat B2 were used as the base and diluent.

[0210] A curing agent Y3 for a two-pack curing type paint was prepared so as to contain each component in the following proportions: 47.5 parts of a hexamethylene diisocyanate prepolymer and 52.5 parts of an ester solvent.

[0211] A base coat B3 was prepared by mixing 100 parts of the base Xl, 20 parts of the curing agent Y3 and 120 parts of the diluent Zl. The ratio of hydroxyl groups to isocyanate groups, OH / NCO, was 1.2.

[0212] < Base coat B4 >

[0213] A base X2 for a two-pack curing type paint was prepared so as to contain each component in the following proportions: 37.5 parts of an acrylic resin having a molecular weight of 21,000 and 62.5 parts of a mixed solvent. The mixed solvent contained an ester solvent and a ketone solvent.

[0214] A curing agent Y4 for a two-pack curing type paint was prepared so as to contain each component in the following proportions: 35 parts of a hexamethylene diisocyanate prepolymer and 65 parts of an ester solvent.

[0215] A diluent Z2 was prepared so as to contain each component in the following proportions: 15.0 parts of a ketone solvent and 85.0 parts of an ester solvent.

[0216] A base coat paint B4 was prepared by mixing 4 parts of the main agent X2, 1 part of the curing agent Y4, and 3 parts of the diluent Z2. In addition, the ratio of hydroxyl groups to isocyanate groups (OH / NCO) was 1.2.

[0217] < Base coat paint B5 >

[0218] A two-liquid curing type paint main agent X3 was prepared containing each component in the following proportions: 35.0 parts of an acrylic resin having a molecular weight of 21,000, 3.5 parts of carbon black, and 60.7 parts of a mixed solvent. The mixed solvent contained an ester-based solvent and a ketone-based solvent.

[0219] The same curing agent Y4 and diluent Z2 as those of the base coat paint B4 were used as the curing agent and the diluent.

[0220] A base coat paint B5 was prepared by mixing 4 parts of the main agent X3, 1 part of the curing agent Y4, and 3 parts of the diluent Z2. In addition, the ratio of hydroxyl groups to isocyanate groups (OH / NCO) was 1.2.

[0221] < Base coat paint B6 >

[0222] A one-liquid curing type acrylic paint was prepared containing each component in the following proportions: 24.0 parts of an acrylic resin, 4.0 parts of a cellulose-based resin, 1.0 part of a plasticizer, and 70.9 parts of a mixed solvent. The mixed solvent contained an ester-based solvent and a ketone-based solvent.

[0223] A diluent Z3 was prepared containing each component in the following proportions: 43.0 parts of a ketone-based solvent, 28.0 parts of an alcohol-based solvent, 9.0 parts of an ester-based solvent, and 20.0 parts of an ether-based solvent.

[0224] A base coat paint B6 was prepared by mixing 100 parts of the one-liquid curing type acrylic paint and 110 parts of the diluent Z3.

[0225] < Base coat paint B7 >

[0226] A two-liquid curing type paint main agent X4 was prepared containing each component in the following proportions: 20.0 parts of a polyester resin and 80.0 parts of a mixed solvent. The mixed solvent contained an aromatic hydrocarbon-based solvent and a ketone-based solvent.

[0227] A two-liquid curing type paint curing agent Y5 was prepared containing each component in the following proportions: 20.0 parts of a hexamethylene diisocyanate prepolymer, 0.6 parts of a curing catalyst, and a mixed solvent in an amount such that the total of all components reached 100 parts. The mixed solvent contained an ester-based solvent and a ketone-based solvent.

[0228] A diluent Z4 was prepared containing each component in the following proportions: 30.0 parts of an aromatic hydrocarbon-based solvent, 20.0 parts of an alcohol-based solvent, and 50.0 parts of a ketone-based solvent.

[0229] A base coat paint B7 was prepared by mixing 10 parts of the base agent X4, 1 part of the curing agent Y5 and 8 parts of the diluent Z4. The ratio of the hydroxyl group to the isocyanate group (OH / NCO) was 1.2.

[0230] < Base coat paint B8 >

[0231] A one-pack curing type acrylic melamine paint was prepared so as to contain each component in the following proportions: 26.3 parts of an acrylic resin, 7.8 parts of an amino resin, 2.4 parts of a polyurethane resin and 60.1 parts of a mixed solvent. The mixed solvent contained an ester solvent and an alcohol solvent.

[0232] A diluent Z5 was prepared so as to contain each component in the following proportions: 40.0 parts of a ketone solvent and 60.0 parts of an ester solvent.

[0233] A base coat paint B8 was prepared by mixing 100 parts of the one-pack curing type acrylic melamine paint and 70 parts of the diluent Z5.

[0234] < Base coat paint B9 >

[0235] A one-pack curing type polyester melamine paint was prepared so as to contain each component in the following proportions: 37.6 parts of a polyester resin, 14.8 parts of an amino resin and 46.6 parts of a mixed solvent. The mixed solvent contained an aromatic hydrocarbon solvent and an alcohol solvent.

[0236] A diluent Z6 was prepared so as to contain each component in the following proportions: 40.0 parts of an aromatic hydrocarbon solvent, 20.0 parts of an ester solvent and 30.0 parts of an alcohol solvent.

[0237] A base coat paint B9 was prepared by mixing 100 parts of the one-pack curing type polyester melamine paint and 50 parts of the diluent Z6.

[0238] < Base coat paint B10 >

[0239] A one-pack curing type acrylic silicone paint was prepared so as to contain each component in the following proportions: 18.8 parts of an acrylic resin, 2.0 parts of a cellulose resin and 79.2 parts of a mixed solvent. The mixed solvent contained an aromatic hydrocarbon solvent, an ester solvent, a ketone solvent and an alcohol solvent.

[0240] A diluent Z7 was prepared so as to contain each component in the following proportions: 55.0 parts of a ketone solvent and 45.0 parts of an alcohol solvent.

[0241] A base coat paint B10 was prepared by mixing 100 parts of the one-pack curing type acrylic silicone paint and 100 parts of the diluent Z7.

[0242] < Base coat paint B11 >

[0243] A one-pack curing type epoxy resin paint was prepared so as to contain each component in the following proportions: 15.0 parts of an epoxy resin, 7.5 parts of a polyurethane resin, and 77.5 parts of a mixed solvent. The mixed solvent contained an aromatic hydrocarbon solvent, a ketone solvent, and an alcohol solvent.

[0244] A diluent Z8 was prepared so as to contain each component in the following proportions: 40.0 parts of an aromatic hydrocarbon solvent, 40.0 parts of a ketone solvent, and 20.0 parts of an alcohol solvent.

[0245] A primer paint B11 was prepared by mixing 100 parts of the one-pack curing type epoxy resin paint and 50 parts of the diluent Z8 in the proportions of 100 parts of the one-pack curing type epoxy resin paint and 50 parts of the diluent Z8.

[0246] <Primer paint B12>

[0247] An alkyd resin paint was prepared so as to contain each component in the following proportions: 22.3 parts of an alkyd resin and 77.7 parts of a mixed solvent. The mixed solvent contained an aromatic hydrocarbon solvent.

[0248] A diluent Z9 was prepared so as to consist of an aromatic hydrocarbon solvent.

[0249] A primer paint B12 was prepared so as to contain each component in the following proportions: 100 parts of the alkyd resin paint and 35 parts of the diluent Z9.

[0250] <Primer paint B13>

[0251] An ultraviolet curing type primer paint B13 was prepared so as to contain each component in the following proportions: 30.0 parts of a polyurethane acrylate, 15.0 parts of an acrylate monomer, 2.0 parts of a cellulose resin, and 53.0 parts of a mixed solvent.

[0252] <Primer paint B14>

[0253] A main agent X5 of a two-pack curing type paint was prepared so as to contain each component in the following proportions: 36.0 parts of an acrylic resin, 4.0 parts of a polycarbonate polyol resin, 0.1 part of a curing catalyst, and 59.9 parts of a mixed solvent. The mixed solvent contained an ester solvent and a ketone solvent.

[0254] A primer paint B14 was prepared by mixing 100 parts of the main agent X5, 25 parts of a curing agent Yl, and 110 parts of a diluent Zl in the proportions of 100 parts of the main agent X5, 25 parts of the curing agent Yl, and 110 parts of the diluent Zl. In addition, the ratio of hydroxyl groups to isocyanate groups, OH / NCO, was 1.2.

[0255] [Preparation of a metal-containing paint]

[0256] <Metal-containing paint Ml>

[0257] A metal-containing coating M1 was prepared, which contained the following components in the following proportions: 2.0 parts of vapor-deposited indium film fragments, 27.0 parts of ketone solvents, 7.8 parts of ether solvents and 63.0 parts of ester solvents, and the pigment weight concentration (PWC) of the vapor-deposited indium film fragments was adjusted to 90.9% by mass.

[0258] <Metal-containing coating M2>

[0259] Prepare a metal-containing coating M2, which contains the following components in the following proportions: 24.7 parts silver compound complex, 73.3 parts alcohol solvent and 2.0 parts ether solvent.

[0260] [Preparation of the top coating]

[0261] <Top Coating T1>

[0262] The main agent for preparing a two-component curing coating contains the following components in the following proportions: 18.4 parts acrylic resin with a molecular weight of 21,000, 9.1 parts acrylic resin with a molecular weight of 10,000, 2.0 parts cellulose resin, and 69.4 parts mixed solvent. The mixed solvent contains ester solvents and ketone solvents.

[0263] A curing agent for preparing a two-component curing coating contains the following components in the following proportions: 54.0 parts hexamethylene diisocyanate prepolymer and 46.0 parts ester solvent.

[0264] A two-component curable topcoat T1 was prepared by mixing 100 parts of the main agent, 15 parts of the curing agent, and 60 parts of the ketone solvent. The ratio of hydroxyl to isocyanate groups (OH / NCO) was 1.2.

[0265] <Top Coating T2>

[0266] A UV-curable topcoat T2 is prepared, comprising the following components in the following proportions: 10.0 parts acrylic resin, 30.0 parts acrylate monomer, 10.0 parts polyurethane acrylate, and 45.4 parts mixed solvent. The mixed solvent contains ester solvents, ketone solvents, and aromatic hydrocarbon solvents.

[0267] [Substrate]

[0268] PC: Polycarbonate sheet

[0269] PET: Polyethylene terephthalate sheet

[0270] SUS304: SUS304 stainless steel sheet

[0271] [Preparation of metal-containing ointments]

[0272] <Metal-containing ointment P1>

[0273] A metal-containing paste P1 was prepared so as to contain each component in the following proportions: 20.0 parts of vapor-deposited indium film chips and 78.0 parts of an alcoholic solvent, and the pigment weight concentration (PWC) of the vapor-deposited indium film chips was adjusted to 90.9 mass%.

[0274] < Metal-containing paste P2 >

[0275] A metal-containing paste P2 was prepared so as to contain each component in the following proportions: 73.0 parts of aluminum powder, 26.0 parts of a hydrocarbon solvent, and 1.0 part of a fatty acid.

[0276] < Metal-containing paste P3 >

[0277] A metal-containing paste P3 was prepared so as to contain each component in the following proportions: 9.0 parts of vapor-deposited aluminum powder film chips, 67.5 parts of an alcoholic solvent, 22.5 parts of an ether solvent, and 1.0 part of silicon dioxide.

[0278] [Additive]

[0279] < Additive 1 >

[0280] Additive 1 was prepared so as to contain each component in the following proportions: 20.0 parts of a cellulose-based resin having a butyryl group content of 55.1 mass% and 80.0 parts of an ester solvent.

[0281] < Additive 2 >

[0282] Additive 2 was prepared so as to contain each component in the following proportions: 20.0 parts of a cellulose-based resin having a butyryl group content of 38.1 mass% and 80.0 parts of an ester solvent.

[0283] < Additive 3 >

[0284] A commercially available silicon-based surface conditioner was used. In addition, the non-volatile component in Additive 3 was 100 mass%.

[0285] [Evaluation of the coating film]

[0286] < Evaluation of mirror design >

[0287] (Evaluation of mirror design (appearance))

[0288] With respect to each of the resulting coating films, the state of the mirror was observed visually, and the mirror design was evaluated by the following criteria. The results are shown in Table 1.

[0289] -Evaluation criteria-

[0290] A: There was clear mapping, and beautiful mirror design

[0291] B: There was mirror design with mapping

[0292] C: Although it was metallic, mirror design with mapping could not be confirmed

[0293] (mirror gloss)

[0294] For each of the obtained coating films, the coating film surface and the vapor deposition surface were used as the measurement surface, and the gloss value was measured. The gloss value was measured using a gloss meter (micro-TRI-gloss cat. 4446 manufactured by BYK Co., Ltd.) in accordance with the parallel light method according to Japanese Industrial Standard JIS Z8741 "Mirror Gloss - Measurement Method", and the gloss values at incident angles of 20°, 60°, and 85° were measured. The results are shown in Tables 1.

[0295] <Wave permeability evaluation>

[0296] (attenuation and transmittance)

[0297] The wave permeability was measured by 2-terminal S (Scattering) parameter measurement according to the free space method using a vector network analyzer (ME7838A manufactured by Anritsu Co.) and an antenna corresponding to the angular frequency band, at 18 GHz to 26.5 GHz and 60 GHz to 90 GHz, and the attenuation (db) and the transmittance (%) at 24 GHz and 78 GHz were evaluated.

[0298] [Examples 101 to 128, Comparative Examples 101 to 109]

[0299] As the base coat, the middle coat, the top coat, and the substrate, the substances described in Tables 1 to 4 were used, respectively, and the coating was performed using an airbrush so as to achieve the film thickness described in Tables 1 to 4, and the coating film was dried and cured under the conditions described in Tables 1 to 4 to obtain a coated article.

[0300] The mirror design and the coating film adhesion of the obtained coated article were evaluated, and the results are shown in Tables 1 to 4.

[0301] [Table 1]

[0302]

[0303] [Table 2]

[0304]

[0305] [Table 3]

[0306]

[0307] [Table 4]

[0308]

[0309] As is clear from Tables 1 to 4, the coated article of the present application has large gloss values at incident angles of 20°, 60° and 85° measured by the parallel light method according to Japanese Industrial Standard JIS Z8741 "Gloss of a mirror surface - Method of measurement", and in addition, exhibits excellent mirror design in the evaluation based on visual observation.

[0310] Further, the coated article of the present application can form a coating film having excellent mirror design even when the heating temperature at the time of coating film formation is about 80°C.

[0311] [Example 201, Comparative Example 201]

[0312] As the base coat material, the middle coat material, the top coat material and the substrate, the materials described in Table 5 were used, respectively, and coating was performed by a spray gun in a manner so as to achieve the film thicknesses described in Table 5, and drying and curing were performed under the coating film formation conditions described in Table 5 to obtain a coated article.

[0313] The radio wave permeability of the obtained coated article was evaluated, and the results are shown in Table 5.

[0314] [Table 5]

[0315]

[0316] As is clear from Table 5, the coated article of the present application has excellent radio wave permeability in the 24 GHz band and the 78 GHz band.

[0317] [Examples 301 to 324, Comparative Examples 301 to 308]

[0318] A metal-containing coating material was prepared, and as the metal-containing paste, solvents 1 to 5, additives 1 to 3 and the substrate, the materials described in Tables 6 to 9 were used, respectively, and the pigment weight concentration (PWC) of the metal pigment was adjusted to the values described in Tables 6 to 9, respectively, and coating was performed by a spray gun in a manner so as to achieve a dry film thickness of 1.0 μm and drying was performed to obtain a coated article. Solvent 1 is an aromatic hydrocarbon solvent, solvent 2 is a ketone solvent, solvent 3 is an ester solvent, solvent 4 is an ethylene glycol ether solvent and solvent 5 is an alcohol solvent.

[0319] The mirror design of the obtained coated article was evaluated, and the results are shown in Tables 6 to 9.

[0320] [Table 6]

[0321]

[0322] [Table 7]

[0323]

[0324] [Table 8]

[0325]

[0326] [Table 9]

[0327]

[0328] As is apparent from Tables 6 to 9, when the metal pigment is the vapor-deposited indium film fragment and the PWC (pigment weight concentration) of the metal pigment is 70.0 mass% or more, a coating film having excellent mirror design properties can be formed.

Claims

1. A coated article, characterized by, has: (a) a primer coating film layer formed from a primer coating material disposed directly or indirectly over a coated object, and (b) a metal-containing coating film layer having a pigment weight concentration (PWC) of 72.7% or more of vapor-deposited indium thin film fragments disposed directly or indirectly over the primer coating film layer, and the primer coating material is a two-pack curable coating material, an acrylic paint, a melamine-based coating material, or an active energy ray-curable coating material, the vapor-deposited indium thin film fragments have an average thickness of 0.001 μm or more and 0.100 μm or less and a cumulative 50% volume particle size D50 of 0.01 μm or more and 1.00 μm or less, in a volume-standardized particle size distribution representing the relationship between the particle size of the vapor-deposited indium thin film fragments and the volume proportion of the vapor-deposited indium thin film fragments of that particle size, there are a first peak and a second peak having a particle size larger than the first peak, the volume of the vapor-deposited indium thin film fragments of the first peak V1 and the volume of the vapor-deposited indium thin film fragments of the second peak V2 satisfy (V1 / V2) x 100 ≧ 25%, the particle size of the vapor-deposited indium thin film fragments of the first peak P1 and the particle size of the vapor-deposited indium thin film fragments of the second peak P2 satisfy 6.0 ≦ P2 / P1 ≦ 12, the coated object has a radio wave transmittance of 75% or more in the 24 GHz band and the 78 GHz band.

2. The coated article of claim 1, wherein, has: (c) an upper coating film layer formed from a two-pack curable coating material or an active energy ray-curable coating material disposed directly or indirectly over the metal-containing coating film layer.

3. The coated article according to claim 1 or 2, characterized in that The following important conditions are satisfied: the coated object has a 20° gloss value of 150 or more and a 60° gloss value of 170 or more.

4. A method for producing a coated article, characterized by, has: (i) a step of directly or indirectly disposing a primer coating film layer based on a primer coating material over a coated object, and (ii) a step of directly or indirectly disposing a metal-containing coating film layer having a pigment weight concentration (PWC) of 72.7% or more of vapor-deposited indium thin film fragments over the primer coating film layer, and the primer coating material is a two-pack curable coating material, an acrylic paint, a melamine-based coating material, or an active energy ray-curable coating material, the vapor-deposited indium thin film fragments have an average thickness of 0.001 μm or more and 0.100 μm or less and a cumulative 50% volume particle size D50 of 0.01 μm or more and 1.00 μm or less, in a volume-standardized particle size distribution representing the relationship between the particle size of the vapor-deposited indium thin film fragments and the volume proportion of the vapor-deposited indium thin film fragments of that particle size, there are a first peak and a second peak having a particle size larger than the first peak, the volume of the vapor-deposited indium thin film fragments of the first peak V1 and the volume of the vapor-deposited indium thin film fragments of the second peak V2 satisfy (V1 / V2) x 100 ≧ 25%, the particle size of the vapor-deposited indium thin film fragments of the first peak P1 and the particle size of the vapor-deposited indium thin film fragments of the second peak P2 satisfy 6.0 ≦ P2 / P1 ≦ 12, the coated object has a radio wave transmittance of 75% or more in the 24 GHz band and the 78 GHz band.

5. A coating group, characterized by includes: (I) a primer coating material, and (II) a metal-containing coating material containing vapor-deposited indium thin film fragments in an amount such that the pigment weight concentration (PWC) in the dried coating film is 72.7% or more, and the base coat is a two-pack curable coating material, an acrylic paint, a melamine-based coating material, or a radiation-curable coating material, the average thickness of the evaporation indium film fragments is 0.001 μm or more and 0.100 μm or less, and the cumulative 50% volume particle size D50 is 0.01 μm or more and 1.00 μm or less, in a volume-standardized particle size distribution representing the relationship between the particle size of the evaporation indium film fragments and the volume proportion of the evaporation indium film fragments of that particle size, there are a first peak and a second peak larger than the first peak, the volume V1 of the evaporation indium film fragments of the first peak and the volume V2 of the evaporation indium film fragments of the second peak satisfy (V1 / V2) x 100 ≧ 25%, the particle size P1 of the evaporation indium film fragments of the first peak and the particle size P2 of the evaporation indium film fragments of the second peak satisfy 6.0 ≦ P2 / P1 ≦ 12, the coated article has a base coat film layer formed of the base coat directly or indirectly provided on a coated object, and a metal-containing coat film layer formed of the metal-containing coating material directly or indirectly provided on the base coat film layer, and the radio wave transmittance at 24 GHz and at 78 GHz of the coated article is 75% or more.

Images