JP2021143379A - Manufacturing method of silver plated body - Google Patents

Abstract

To provide a manufacturing method of a silver plated body in which adhesive force between a silver plated layer and a top coat layer is improved.SOLUTION: In a manufacturing method of a silver plated body having at least an undercoat layer, a silver plated layer and a top coat layer in this order on a substrate, the top coat layer is formed, by applying on the substrate and by bridging a coating composition containing at least an acrylic polyol resin, a compound having two or more isocyanate groups and a compound having two or more carbodiimide groups.SELECTED DRAWING: None

Description

The present invention relates to a method for producing a silver-plated coated body having at least a silver-plated layer and a topcoat layer on a base material. More specifically, the present invention relates to a manufacturing method capable of obtaining a silver-plated coated body having an improved adhesive force between the silver-plated layer and the topcoat layer.

A silver-plated coated body having a silver-plated layer on a base material such as metal or plastic is used as a design material, a reflective material, or the like because silver has the highest reflective luster among metals. Further, it is a material that can be effectively used as, for example, an electromagnetic wave shielding material by utilizing the high conductivity of silver.

The silver-plated layer is a useful material that exhibits high reflective luster and high conductivity even if it is a thin film, but its mechanical strength is weak because it is thin and soft. In order to make up for such a defect, a method of providing a top coat layer on the surface using various hard coat materials is known. For example, Japanese Patent Application Laid-Open No. 2000-129448 (Patent Document 1) describes that various resins such as a liquid epoxy resin and an unsaturated polyester resin can be used for the top coat layer. However, even if the top coat layer is provided on the silver plating layer, there is a problem that sufficient adhesive force between the silver plating layer and the top coat layer cannot be obtained, and especially in a high temperature and high humidity environment or an atmosphere containing salt water. , This problem becomes even more prominent.

Various topcoat layers have been proposed in order to solve the problem of adhesive strength between the silver plating layer and the topcoat layer. For example, Japanese Patent Application Laid-Open No. 2003-155580 (Patent Document 2), Japanese Patent Application Laid-Open No. 2004-203014, etc. describe that a silicone acrylic paint having a specific glass transition temperature is used, and Japanese Patent Application Laid-Open No. 2008-106081 The publication describes that a specific ultraviolet curable resin is used for the top coat layer. Further, Japanese Patent Application Laid-Open No. 2015-7672 (Patent Document 3), Japanese Patent Application Laid-Open No. 2015-191180 (Patent Document 4) and the like describe a top coat layer crosslinked with a carbodiimide compound, an isocyanate compound and an epoxy compound. However, even in these methods, the adhesive strength between the silver plating layer and the top coat layer is not sufficient, and further improvement in the adhesive strength has been desired.

Japanese Unexamined Patent Publication No. 2000-129448 Japanese Unexamined Patent Publication No. 2003-155580 Japanese Unexamined Patent Publication No. 2015-7672 JP-A-2015-191180

An object of the present invention is to provide a silver-plated coating body having improved adhesive strength between the silver-plated layer and the top coat layer, and to provide a silver-plated coating body capable of obtaining sufficient adhesive strength even in a particularly harsh environment. The task is to do.

The above object of the present invention is achieved by the invention described below.
In a method for producing a silver-plated coating body having at least an undercoat layer, a silver plating layer and a topcoat layer on a substrate in this order, the topcoat layer is at least an acrylic polyol resin, a compound having two or more isocyanate groups, and a compound having two or more isocyanate groups. A method for producing a silver-plated coating body, which comprises applying a coating composition containing a compound having two or more carbodiimide groups onto a substrate and cross-linking the coating composition.

According to the method for producing a silver-plated coated body of the present invention, it is possible to improve the adhesiveness between the silver-plated layer and the top coat layer and provide a silver-plated coated body having excellent durability.

Hereinafter, the present invention will be described in detail.

The silver-plated coating body obtained by the present invention is a silver-plated coating body having at least an undercoat layer, a silver plating layer, and a topcoat layer on the base material in this order, and the topcoat layers are two acrylic polyol resins. It is obtained by applying and cross-linking a coating composition containing the above compound having an isocyanate group and the compound having two or more carbodiimide groups.

The acrylic polyol resin contained in the coating composition of the top coat layer in the present invention is an acrylic resin having two or more hydroxy groups in one molecule. These acrylic polyol resins are obtained by copolymerizing a (meth) acrylic acid ester containing a hydroxy group with a compound having a polymerizable unsaturated group. Examples of the (meth) acrylic acid ester containing a hydroxy group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate and the like. Can be mentioned. Examples of the compound having a polymerizable unsaturated group include (meth) acrylic acid ester, styrene, α-methylstyrene and the like. These polymerizable compounds can also be copolymerized by combining two or more kinds.

The above acrylic polyol resin is commercially available as an acrylic resin for curing isocyanate. For example, the Acrydic (registered trademark) series of DIC Corporation and the Hitaroid (registered trademark) series of Hitachi Kasei Co., Ltd. can be obtained and used. Can be done. Further, the main agent of a commercially available two-component curable acrylic urethane-based paint can also be used as the acrylic polyol resin of the present invention. For example, Polynal (registered trademark) 800 series commercially available from Ohashi Chemical Industries, Ltd. can be obtained and used. These acrylic polyol resins may be used alone or in combination of a plurality of acrylic polyol resins.

The compound having two or more isocyanate groups (hereinafter, also referred to as a polyisocyanate compound) contained in the coating composition of the top coat layer in the present invention is derived from aromatic diisocyanate, aliphatic or aliphatic diisocyanate, or any of them. Can be exemplified by the polyisocyanate compound. Among them, a polyisocyanate compound composed of an aliphatic or alicyclic diisocyanate is preferable because it is excellent in handleability and weather resistance. These may be any of a biuret type, an isocyanate type, an adduct type, and a bifunctional type. These polyisocyanate compounds are, for example, the Duranate (registered trademark) series marketed by Asahi Kasei Corporation, the Barnock (registered trademark) series marketed by DIC Corporation, and the Coronate (registered trademark) marketed by Tosoh Corporation. The (trademark) series or the Mytec (registered trademark) series commercially available from Mitsubishi Chemical Corporation can be obtained and used. Further, a curing agent of a commercially available two-component curable acrylic urethane-based paint can also be used as the polyisocyanate compound of the present invention. These polyisocyanate compounds may be used alone or in combination of a plurality of compounds.

The suitable content of the polyisocyanate compound contained in the coating composition of the top coat layer in the present invention depends on the amount of hydroxyl groups of the acrylic polyol resin contained in the coating composition of the top coating layer, but the coating composition of the top coating layer It is preferably 5 to 30% by mass based on the total solid content of the above. If the amount of the polyisocyanate compound is too large or too small, the strength of the layer cannot be sufficiently maintained. The total solid content of the coating material referred to here represents the total amount of the total coating composition excluding the solvent component that evaporates to form a layer after coating.

The coating composition of the top coat layer in the present invention further contains a compound having two or more carbodiimide groups (hereinafter, also referred to as a polycarbodiimide compound). Such a carbodiimide compound can be synthesized by a known method, and can be produced, for example, from a diisocyanate compound by a condensation reaction accompanied by decarbonization in the presence of a catalyst that promotes carbodiimide formation of isocyanate. The diisocyanate compound may be any of an aliphatic diisocyanate, an alicyclic diisocyanate, and an aromatic diisocyanate. The polycarbodiimide compound thus synthesized has an isocyanate group remaining at the molecular terminal, but may be completely or partially blocked by a compound that reacts with the isocyanate group. Further, other compounds such as polyalkylene diol may be added or copolymerized as required.

The above polycarbodiimide compound can be used by obtaining the carbodilite (registered trademark) series commercially available from Nisshinbo Chemical Co., Ltd., for example, carbodilite V-03, carbodilite V-04PF, carbodilite V-05, carbodilite V. -07, carbodilite V-09 and the like can be mentioned.

The preferable content of the polycarbodiimide compound contained in the coating composition of the top coat layer in the present invention is preferably 0.5 to 5% by mass with respect to the total solid content of the coating composition of the top coat layer. If the content of the polycarbodiimide compound is too large or too small, the effect of improving the adhesiveness is reduced.

In addition to the acrylic polyol resin described above, the coating composition of the top coat layer in the present invention includes, for example, epoxy resin, vinyl chloride resin, hydrocarbon resin, ketone resin, phenoxy resin, polyamide resin, ethyl cellulose, nitrocellulose, vinyl acetate. , ABS resin, melamine resin, urea resin, benzoguanamine resin, unsaturated polyester resin, alkyd resin, silicon resin and other other resins can be contained. In that case, the content of the resin other than the acrylic polyol resin is preferably 30% by mass or less of the content of the acrylic polyol resin, and further, a curing agent suitable for the above-mentioned various resins can be contained.

As a method for providing the top coat layer, it is common to dissolve or dilute the above-mentioned coating composition in an organic solvent and apply it. Examples of such an organic solvent include toluene, xylene, cyclohexane, hydrocarbons such as T-SOL (registered trademark) 100FLUID (trade name, manufactured by JXTG Energy Co., Ltd.), and alcohols such as methanol, ethanol, isopropyl alcohol, and butyl alcohol. Examples include ethers such as butyl cellosolve, tetrahydrofuran and methyl cellosolve acetate, esters such as ethyl acetate, n-butyl acetate, isobutyl acetate and isobutyl isobutyrate, and ketones such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone. These organic solvents are appropriately selected depending on the solubility of the coating composition, the drying time and temperature, the surface quality improvement of the coated surface, and the like, and may be used alone or in combination of two or more.

As a coating method of the coating composition used for providing the top coat layer, a conventionally known coating method may be used, for example, a gravure roll method, a reverse roll method, a dip roll method, a bar coater method, a knife coater method, and an air spray. Examples include a method, an airless spray method, and a dip method. Among these, the air spray method, which can be applied even to a complicated surface shape, is a particularly preferable method.

In order to dry and crosslink the coating composition used for providing the top coat layer after coating, it can be naturally dried at room temperature, but it is preferable to heat it to promote the crosslinking reaction. A higher heating temperature is preferable because the cross-linking reaction can be promoted, but if the temperature is too high, the base material may be deformed, so it is necessary to heat within a temperature range in which the base material is not deformed. Usually, heating is performed at 60 to 80 ° C. for about 20 to 120 minutes.

The thickness of the top coat layer is preferably in the range of 10 to 50 μm. If the layer is too thin, the function of protecting the silver plating layer cannot be obtained, and a uniform coating film cannot be formed. On the other hand, if it is too thick, the light transmission distance becomes long and the light loss increases, which is not preferable because the reflectance of the silver plating layer is lowered.

Coloring materials such as pigments and dyes and matting agents may be added to the coating composition of the top coat layer in the present invention in order to improve the design. Pigments include organic pigments such as carbon black, quinacridone, naphthol red, cyanine blue, cyanine green, and Hansa yellow, and inorganic pigments such as titanium oxide, aluminum oxide, calcium carbonate, barium sulfate, mica, petals, and composite metal oxides. Fine particles can be mentioned. Examples of dyes include azo-based, anthraquinone-based, indicoid-based, sulfide-based, triphenylmethane-based, xanthene-based, alizarin-based, acridine-based, quinoneimine-based, thiazole-based, methine-based, nitro-based, and nitroso-based dyes. Can be mentioned. Examples of the matting agent include inorganic fine particles such as silica, talc and barium sulfate, and organic fine particles such as acrylic, urethane, melamine, nylon and polyester.

The coating composition of the top coat layer in the present invention may further contain a leveling agent, a metal powder, a glass powder, an antibacterial agent, an antioxidant, an ultraviolet absorber, a light stabilizer and the like as additives.

The undercoat layer of the present invention preferably has high adhesion to the silver-plated layer. For example, in addition to the undercoat layer described in JP-A-10-309774 and JP-A-2002-256455, a polyol. An undercoat layer obtained by applying a urethane-based coating composition in which a resin and a polyisocyanate compound are mixed, an epoxy-based coating composition in which an epoxy resin and an amine compound are mixed, and cross-linking can be used. Among these, an undercoat layer obtained by applying an acrylic urethane-based coating composition in which an acrylic polyol resin and a polyisocyanate compound are mixed and cross-linking is preferable from the viewpoint of handleability and adhesion to a silver plating layer.

As the acrylic polyol resin used in the coating composition of the undercoat layer, the same ones used in the coating composition of the topcoat layer can be used.

Further, as the polyisocyanate compound, an aromatic diisocyanate or a polyisocyanate compound composed of either an aliphatic or an aliphatic diisocyanate can be exemplified, and these are biuret type, isocyanurate type, adduct type, and bifunctional type. It may be any of. These polyisocyanate compounds are, for example, the Duranate series marketed by Asahi Kasei Corporation, the Barnock series marketed by DIC Corporation, the Coronate series marketed by Tosoh Corporation, or Mitsubishi Chemical Corporation. You can obtain and use the more commercially available Mitec series. These polyisocyanate compounds may be used alone or in combination of a plurality of compounds.

The coating composition of the undercoat layer in the present invention may further contain a silane coupling agent, a leveling agent, a curing accelerator, inorganic fine particles and the like as additives.

As a method for providing the undercoat layer, it is common to dissolve or dilute the above-mentioned coating composition in an organic solvent and apply the coating composition. As such an organic solvent, the same type as the organic solvent used when forming the top coat layer can be used. These organic solvents are appropriately selected depending on the solubility of the coating composition, the drying time and temperature, the surface quality improvement of the coated surface, and the like, and may be used alone or in combination of two or more.

As a coating method of the coating composition used for providing the undercoat layer, a conventionally known coating method may be used, for example, a gravure roll method, a reverse roll method, a dip roll method, a bar coater method, a knife coater method, and an air spray. Examples include a method, an airless spray method, and a dip method. Among these, the air spray method, which can be applied even to a complicated surface shape, is a particularly preferable method.

In order to dry and crosslink the coating composition used for providing the undercoat layer after coating, it can be naturally dried at room temperature, but it is preferable to heat it to promote the crosslinking reaction. A higher heating temperature is preferable because the cross-linking reaction can be promoted, but if the temperature is too high, the base material may be deformed, so it is necessary to heat within a temperature range in which the base material is not deformed. Usually, heating is performed at 60 to 80 ° C. for about 20 to 120 minutes. The film thickness of the undercoat layer is preferably 5 to 30 μm, but is not particularly limited.

The silver-plated body obtained by the present invention has a silver-plated layer on the undercoat layer. The method for forming the silver plating layer may be either dry plating such as a vapor deposition method or a sputtering method, or wet plating such as electrolytic plating or electroless plating, but the silver plating layer is formed by electroless plating. The method is simple and preferable.

A preferred method for forming an electroless silver plating layer on the undercoat layer is to treat the surface of the undercoat layer on which the electroless silver plating layer is formed with an active treatment liquid containing tin (II) chloride to tin (II). ) Ions are supported on the surface of the undercoat layer, and an electroless silver plating layer is formed on the activated undercoat layer by a silver mirror reaction.

Examples of the treatment method for treating with an active treatment liquid containing tin (II) chloride include a method of immersing the surface of the undercoat layer in the active treatment liquid and an active treatment containing tin (II) chloride on the surface of the undercoat layer. There is a method of applying a liquid and the like. As a coating method, spray coating regardless of the shape of the base material is preferable. Further, it is preferable to wash the activation treatment liquid excessively attached to the surface with deionized water.

After the step of treating with the activation treatment liquid for silver mirror, it is preferable to provide a step of performing activation treatment with silver ions. Examples of the activation treatment with silver ions include treatment with an aqueous silver nitrate solution. The concentration of the silver nitrate aqueous solution used here is preferably a dilute solution of 0.1 mol or less per liter, and this solution is brought into contact with the tin (II) chloride-treated undercoat layer. Examples of the method of this activation treatment include a method of immersing the undercoat layer treated with tin (II) chloride in the above-mentioned treatment liquid or a method of spray coating.

The electroless silver plating layer is formed by the silver mirror reaction by subjecting two solutions, an ammoniacal silver nitrate solution containing silver nitrate and ammonia, and a reducing agent solution containing a reducing agent and a strong alkaline component, to the surface of the undercoat layer. Apply to mix above. As a result, a redox reaction occurs to precipitate metallic silver, and a silver film is formed to form an electroless silver plating layer.

Examples of the reducing agent solution include an aqueous solution containing an aldehyde compound such as glucose and glyoxal, and an aqueous solution containing a hydrazine compound such as hydrazine sulfate, hydrazine carbonate or hydrazine hydrate.

Some additives can also be added to the aqueous ammoniacal silver nitrate solution to produce good silver. For example, monoethanolamine, tris (hydroxymethyl) aminomethane, 2-amino-2-hydroxymethyl-1,3-propanediol, 1-amino-2-propanol, 2-amino-1-propanol, diethanolamine, diisopropanol. Examples thereof include amino alcohol compounds such as amines, triethanolamines and triisopropanolamines, amino acids such as glycine, alanine and sodium glycine or salts thereof, but are not particularly limited.

As a method of applying the two solutions of the ammoniacal silver nitrate solution and the reducing agent solution so as to be mixed on the surface forming the electroless silver plating layer, the two aqueous solutions are mixed in advance and the mixed solution is sprayed. A method of spraying on the surface of the undercoat layer using a gun or the like, a method of spraying using a concentric spray gun having a structure in which two types of aqueous solutions are mixed in the head of the spray gun and immediately discharged, and two types of aqueous solutions are sprayed. There is a method of discharging and spraying each from a double-headed spray gun having a spray nozzle, a method of spraying two kinds of aqueous solutions at the same time using two separate spray guns, and the like. These can be arbitrarily selected according to the situation.

Subsequently, it is preferable to wash the surface of the silver-plated layer with deionized water or purified distilled water to remove the solution after the silver mirror reaction remaining on the surface. Further, before providing the above-mentioned top coat layer on the silver plating layer, for the purpose of stabilizing the precipitated metallic silver, the solution is immersed in a solution containing a compound having a reaction or affinity with silver, or the solution is applied. Surface treatment can be performed.

As the base material of the silver-plated coated body obtained by the present invention, various plastics, metals, glasses, rubbers and the like are used. Examples of plastics include polycarbonate resin, acrylic resin, ABS resin, vinyl chloride resin, epoxy resin, phenol resin, polyethylene terephthalate (PET) resin, polybutylene terephthalate (PBT) resin and other polyester resins, fluororesin, polypropylene ( Examples thereof include a PP) resin, a resin obtained by combining these, and a fiber-reinforced plastic (FRP) reinforced with organic fibers such as nylon fiber and pulp fiber, but the present invention is not particularly limited. Examples of the metal include iron, aluminum, stainless steel, copper, brass and the like, but the metal is not particularly limited. The glass is also not particularly limited, such as inorganic glass or plastic glass.

Hereinafter, the present invention will be described with reference to examples, but this description does not limit the present invention. In addition,% as a unit in the following description is based on mass unless otherwise specified.

<Example 1>
Acrylic polyol resin (Mirror Shine Undercoat Clear D-1 manufactured by Ohashi Chemical Industries, Ltd.), polyisocyanate compound (hardener N for mirror shine undercoat manufactured by Ohashi Chemical Industries, Ltd.) and thinner (methyl ethyl ketone and butyl cell solve) in mass ratio (Mixed at a ratio of 1: 1) was mixed at a mass ratio of 10: 2:10. Further, 2% of 3-mercaptopropyltrimethoxysilane and 2% of 3-isocyanatepropyltrimethoxysilane were added to this coating composition to obtain an undercoat coating composition. This coating composition was spray-coated on an ABS resin plate whose surface was washed and dried with isopropanol, and then heated and dried at 80 ° C. for 1 hour to form an undercoat layer having a thickness of 20 μm.

0.1 mol of hydrochloric acid and 0.1 mol of stannous chloride were added to water to prepare 1000 g of a silver mirror activation treatment solution, which was sprayed onto the undercoat layer with a spray gun for activation treatment, and then deionized. Washed with water. Subsequently, 0.05 mol of silver nitrate was dissolved in water to make 1000 g, and this liquid was sprayed with a spray gun to perform activation treatment with silver ions, and then washed with deionized water.

The silver mirror plating solution was prepared as follows. A silver nitrate solution prepared by dissolving 20 g of silver nitrate in deionized water to make 1000 g and another ammonia solution prepared by dissolving 100 g of a 28% aqueous ammonia solution and 5 g of monoethanolamine in deionized water to make 1000 g were prepared. Prior to use, these silver nitrate solutions and ammonia solutions were mixed 1: 1 to obtain an ammoniacal silver nitrate solution. Next, a reducing agent solution prepared by dissolving 10 g of hydrazine sulfate, 5 g of monoethanolamine, and 10 g of sodium hydroxide in deionized water to make 1000 g was prepared.

The ammoniacal silver nitrate solution and the reducing agent solution thus obtained are simultaneously sprayed using a double-headed spray gun to form a silver-plated layer, washed with deionized water, and after the surface water is sufficiently removed. , 45 ° C. for 30 minutes.

A top coat layer was provided on the silver plating layer. Acrylic polyol resin (Polynal No. 800 (HN-INP) manufactured by Ohashi Chemical Industries, Ltd .: Main agent of two-component acrylic urethane paint, solid content 50%) 100 parts by mass of polyisocyanate compound (Bernock DN manufactured by DIC Co., Ltd.) −981: Isocyanurate of aliphatic diisocyanate, solid content 75%) is added by 11 parts by mass, thinner (Shinner No. 6820 manufactured by Ohashi Chemical Industries, Ltd.) is added by 40 parts by mass, and a polycarbodiimide compound (manufactured by Nisshinbo Chemical Industries, Ltd.) is added. Carbodilite V-03: solid content 50%, carbodiimide equivalent 217) was added in an amount of 1 part by mass to prepare a topcoat layer coating composition. This topcoat layer coating composition was spray-coated on the silver-plated layer with a spray gun and then heated and dried at 80 ° C. for 30 minutes to form a 20 μm topcoat layer. In this way, the silver-plated body of Example 1 obtained by subjecting the ABS resin to silver mirror plating was obtained.

<Example 2>
In the top coat layer coating composition of Example 1, the amount of the polycarbodiimide compound added was 2 parts by mass, and the silver-plated coating body of Example 2 was obtained in the same manner as in Example 1.

<Example 3>
In the top coat layer coating composition of Example 1, the amount of the polycarbodiimide compound added was 4 parts by mass, and the silver-plated coating body of Example 3 was obtained in the same manner as in Example 1.

<Example 4>
In the top coat layer coating composition of Example 1, the amount of the polycarbodiimide compound added was 8 parts by mass, and the silver-plated coating body of Example 4 was obtained in the same manner as in Example 1.

<Example 5>
In the top coat layer coating composition of Example 1, the polycarbodiimide compound was changed to carbodilite V-05 (solid content 100%, carbodiimide equivalent 262) manufactured by Nisshinbo Chemical Co., Ltd., except that the addition amount was 2 parts by mass. A silver-plated coated body of Example 5 was obtained in the same manner as in Example 1.

<Example 6>
In the top coat layer coating composition of Example 1, the polycarbodiimide compound was changed to carbodilite V-07 (solid content 50%, carbodiimide equivalent 200) manufactured by Nisshinbo Chemical Co., Ltd., except that the addition amount was 2 parts by mass. A silver-plated coated body of Example 6 was obtained in the same manner as in Example 1.

<Example 7>
In the top coat layer coating composition of Example 1, the polycarbodiimide compound was changed to Carbodilite V-04PF (solid content 100%, carbodiimide equivalent 336) manufactured by Nisshinbo Chemical Co., Ltd., but the same as in Example 1 was carried out. A silver-plated coating body of 7 was obtained.

<Comparative example 1>
In the top coat layer coating composition of Example 1, a top coat layer coating composition was obtained without adding a polycarbodiimide compound, and the silver-plated coating body of Comparative Example 1 was obtained in the same manner as in Example 1.

The adhesion of the silver-plated sample was evaluated under the following conditions. After scratching the coated sample with a cutter knife so that it reaches the ABS base material from the top coat layer surface, these samples are subjected to a salt spray tester (model STP-90) of Suga Test Instruments Co., Ltd. 5% saline was sprayed in an environment of 35 ° C. for 10 days. The sample after spraying with salt water is washed with water, dried, and the cellophane tape is strongly attached from the part where the cross is scratched, and then the tape is peeled off. bottom. The results are shown in Table 1.
○ ； The peeling of the top coat layer cannot be confirmed with the naked eye △ ； The width of the widest part of the peeling of the top coat layer is less than 2 mm from the center of the cut line × ； The width of the widest part of the peeling of the top coat layer is cut 2 mm or more from the center of the line

As is clear from Table 1, according to the present invention, it is possible to provide a method for producing a silver-plated coated body in which the adhesive force between the silver-plated layer and the topcoat layer is improved.

Claims (1)

In a method for producing a silver-plated coating body having at least an undercoat layer, a silver plating layer and a topcoat layer on a substrate in this order, the topcoat layer is at least an acrylic polyol resin, a compound having two or more isocyanate groups, and a compound having two or more isocyanate groups. A method for producing a silver-plated coating body, which comprises applying a coating composition containing a compound having two or more carbodiimide groups onto a substrate and cross-linking the coating composition.