JP2020158791A - Black color plating film - Google Patents

Abstract

To provide the black color plating film and a laminated plating film having the black color plating film, wherein the black color plating film is excellent in blackness and water repellency, and is also excellent in slidability.SOLUTION: The black color plating film containing nickel is characterized by further containing phosphorus and sulfur and also containing fluororesin particles, the laminated plating film has a black color plating film on a surface, and the black color plating film is formed on a nickel plating film containing nickel and phosphorus.SELECTED DRAWING: Figure 1

Description

The present invention relates to a black plating film. More specifically, the present invention has, for example, a black plating film and a method for producing the same, and the black plating film, which can be suitably used for members requiring black color and water repellency in optical members, medical devices, and the like. The present invention relates to a laminated plating film and a method for producing the same.

In recent years, a blackening treatment layer containing nickel, nickel oxide and zinc oxide has been proposed as a blackening film instead of the chromate film which is a black plating film (see, for example, Patent Document 1). The blackening treatment layer is said to have an excellent black appearance and corrosion resistance.

However, since the blackening treatment layer does not have sufficient blackness, improvement in blackness is desired, and improvement in water repellency is desired because it is inferior in water repellency.

Japanese Unexamined Patent Publication No. 2006-28881

The present invention has been made in view of the above-mentioned prior art, and is a black plating film having excellent blackness and water repellency and also excellent slidability, a laminated plating film having the black plating film, and An object of the present invention is to provide a laminated plating film having a black plating film which is excellent in blackness and water repellency and also excellent in slidability, and a method for producing the same.

The present invention
(1) A black plating film containing nickel, which further contains phosphorus and sulfur and also contains fluororesin particles.
(2) The black plating film according to (1) above, wherein the L value of the black plating film is 3 or less.
(3) A method for producing a black plating film, at least one carboxylic acid and fluorine selected from the group consisting of nickel compounds, phosphorus compounds, monocarboxylic acids, polycarboxylic acids, oxycarboxylic acids and salts thereof. After forming a black plating film forming film with a black plating film forming plating solution containing resin particles, the black plating film forming film and a plating film containing thiourea, alkylenediamine and aromatic sulfonate are contained. A method for producing a black plating film, which comprises contacting with a blackening treatment liquid to form a black plating film.
(4) A black plating film produced by the method for producing a black plating film according to (3) above.
(5) A laminated plating film having a black plating film on its surface, characterized in that the black plating film according to (1) or (2) above is formed on a nickel plating film containing nickel and phosphorus. Laminated plating film,
(6) A method for producing a laminated plating film having a black plating film on the surface, which is selected from the group consisting of nickel compounds, phosphorus compounds, monocarboxylic acids, polycarboxylic acids, oxycarboxylic acids and salts thereof. A nickel plating film is formed by forming a nickel plating film with a plating solution for forming a nickel plating film containing one kind of carboxylic acid, and the formed nickel plating film, a nickel compound, a phosphorus compound, a monocarboxylic acid, a polycarboxylic acid, an oxycarboxylic acid, and the like. A black plating film forming film is formed on the nickel plating film by contacting a black plating film forming plating solution containing at least one carboxylic acid selected from the group consisting of these salts and fluororesin particles. Laminate plating, which comprises contacting the black plating film forming film with a plating film blackening treatment solution containing thiourea, alkylenediamine and aromatic sulfonate to form a black plating film. The present invention relates to a method for producing a film, and (7) a laminated plating film produced by the method for producing a black plating film according to (6) above.

According to the present invention, there is provided a black plating film having excellent blackness and water repellency, and also having excellent slidability, and a method for producing the same. Further, according to the present invention, there is provided a laminated plating film having a black plating film which is excellent in blackness and water repellency and also excellent in slidability, and a method for producing the same.

6 is a scanning electron micrograph of a cross section of a laminated plating film having a black plating film obtained in Example 1.

As described above, the black plating film of the present invention is a black plating film containing nickel, and is characterized by further containing phosphorus and sulfur and containing fluororesin particles. Further, the laminated plating film of the present invention is characterized in that the black plating film is formed on the nickel plating film containing nickel and phosphorus as described above.

Since the black plating film of the present invention and the laminated plating film having the black plating film have the above-mentioned constituent requirements, they are excellent in blackness and water repellency, and are also excellent in slidability.

Generally, in order to enhance the water repellency of the black plating film made of nickel oxide, it is conceivable to include water-repellent fluororesin particles in the black plating film. However, when the black plating film contains fluororesin particles, the black plating film turns brown, and the blackness is rather lowered.

On the other hand, the black plating film of the present invention is excellent in blackness and water repellency even though it contains fluororesin particles, and is also excellent in slidability.

The black plating film of the present invention is black after forming a black plating film forming film with a black plating film forming plating solution containing a nickel compound, a phosphorus compound, a specific carboxylic acid (salt), and fluororesin particles. It can be produced by contacting a coating film for forming a plating film with a plating film blackening treatment solution containing thiourea, alkylenediamine and aromatic sulfonate.

Further, the laminated plating film of the present invention is formed by forming a nickel plating film with a plating solution for forming a nickel plating film containing a nickel compound, a phosphorus compound and a specific carboxylic acid (salt), and the nickel plating film and nickel formed. A plating solution for forming a black plating film containing a compound, a phosphorus compound, a specific carboxylic acid (salt), and fluororesin particles is brought into contact with each other to form a black plating film forming film on the nickel plating film. It can be produced by contacting a black plating film forming film with a plating film blackening treatment solution containing thiourea, alkylenediamine and aromatic sulfonate to form a black plating film.

In the following, for convenience of explanation of the present invention, a method of manufacturing the laminated plating film and a black plating film formed on the surface of the laminated plating film will be described along the flow of the manufacturing process of the laminated plating film of the present invention. However, the present invention is not limited to this method.

In the present invention, as described above, the nickel plating film is formed on the base material, and the black plating film is formed on the formed nickel plating film to form a laminated plating film having the black plating film on the surface. Can be manufactured. A resin layer such as an acrylic resin or polyester may be formed on the surface of the black plating film as long as the object of the present invention is not impaired.

Examples of the material used for the base material include steel materials, resins, glass, ceramics, and the like, but the present invention is not limited to these examples.

Examples of the steel material include general structural rolled steel materials such as SS330, SS400, SS490 and SS540 specified in JIS G3101, rolled steel materials such as SM400, SM490 and SM520 specified in JIS G3106, S10C and S12C. Carbon steel materials specified in JIS G4051 such as S15C, carbon tool steel materials specified in JIS G4401 such as SK140, SK120, SK105, and austenite stainless steel specified in JIS G4304 such as SUS301, SUS303, SUS304. Steel, austenite-ferrite-based stainless steel specified in JIS G4304 such as SUS329J1, SUS405, SUS410L, SUS430, SUS434 and other ferrite-based stainless steel specified in JIS G4304, SUS403, SUS410 and other JIS G4304. Examples thereof include martensite-based stainless steels, but the present invention is not limited to these examples.

Examples of the resin include polyester such as polyethylene terephthalate and polybutylene terephthalate, polyamide such as nylon 66, acrylic resin such as polyimide and polymethylmethacrylate, styrene resin such as polycarbonate, polystyrene, AS resin and ABS resin, and vinyl chloride. Examples thereof include resins, but the present invention is not limited to these examples.

The shape of the base material is not particularly limited, and the shape is preferably selected as appropriate according to the use of the black plating film and the laminated plating film of the present invention. Examples of the shape of the base material include a flat plate shape, a corrugated plate shape, a film shape, a wire rod shape, a rod shape, a spherical shape, a cube shape, a rectangular parallelepiped shape, and a shape of a molded body molded into a predetermined shape. Is not limited to such examples.

A base material having a nickel plating film formed on the surface can be produced by bringing the base material into contact with a plating solution for forming a nickel plating film. The contact between the base material and the nickel plating film forming plating solution can be performed, for example, by immersing the base material in the nickel plating film forming plating solution.

In the following, as an embodiment when the base material and the plating solution for forming a nickel plating film are brought into contact with each other, the case where the base material is a metal base material will be mainly described, but the present invention describes the embodiment. It is not limited to the embodiment.

When a nickel plating film is formed with lipids adhering to the surface of the base material, the adhesion of the nickel plating film to the base material is reduced. Therefore, when lipids are attached to the surface of the base material, from the viewpoint of improving the adhesion of the nickel plating film to the base material, the nickel plating film is formed in advance before being formed on the surface of the base material. It is preferable to degrease the base material. The degreasing of the base material can be performed, for example, by immersing the base material in an alkaline degreasing solution. Examples of the alkaline degreasing solution include an aqueous solution of an alkali metal compound such as sodium hydroxide. The alkaline degreasing solution may contain a surfactant, if necessary, from the viewpoint of improving the degreasing efficiency.

When a metal base material is used as the base material, it is preferable that the base material is treated with an acidic treatment liquid from the viewpoint of improving the adhesion of the nickel plating film. The treatment of the base material with the acidic treatment liquid can be performed, for example, by immersing the base material in the acidic treatment liquid. Examples of the acidic treatment liquid include hydrochloric acid, sulfuric acid aqueous solution, nitric acid aqueous solution, and the like, but the present invention is not limited to these examples.

When the base material is a metal base material, it is preferable to attach palladium to the surface of the base material from the viewpoint of firmly adhering the nickel plating film to the surface of the base material. Examples of the method of adhering palladium to the surface of the base material include a method of immersing the base material in an acidic solution of a palladium compound. Examples of the palladium compound include palladium chloride and palladium sulfate, but the present invention is not limited to these examples. Further, as the acidic solution, an acidic aqueous solution is generally used. Examples of the acid used in the acidic solution include hydrochloric acid, sulfuric acid aqueous solution, nitric acid aqueous solution, and the like, but the present invention is not limited to these examples.

When a stainless steel base material is used as the base material, nickel strike plating is applied to the surface of the base material in advance from the viewpoint of improving the adhesion of the nickel plating film used in the present invention to the base material. Is preferable.

When forming a nickel plating film on the surface of a base material, a plating solution for forming a nickel plating film is used. As the nickel plating film forming plating solution, a nickel plating film forming plating solution containing a nickel compound, a phosphorus compound and a specific carboxylic acid (salt) can be used.

Examples of the nickel compound include nickel chloride, nickel sulfate, nickel nitrate, nickel phosphate, nickel acetate, nickel carbonate, nickel sulfamate, nickel formate, nickel citrate, nickel stearate, nickel oxalate and the like. The present invention is not limited to such examples. Each of these nickel compounds may be used alone, or two or more kinds may be used in combination. Among these nickel compounds, nickel sulfate and nickel nitrate are preferable, and nickel sulfate is more preferable, from the viewpoint of enhancing the adhesion between the base material and the black plating film.

The content of the nickel compound in the plating solution for forming the nickel plating film is preferably 3 g / L or more, more preferably 5 g / L or more, still more preferably 10 g / L, from the viewpoint of enhancing the adhesion between the base material and the black plating film. It is L or more, and is preferably 30 g / L or less, more preferably 25 g / L or less, still more preferably 20 g / L or less, from the viewpoint of enhancing the adhesion between the base material and the black plating film.

The phosphorus compound is a component for promoting the precipitation of nickel on the surface of the substrate. Examples of the phosphorus compound include hypophosphorous acid alkali metal salts such as hypophosphorous acid, sodium hypophosphate and potassium hypophosphite, and hypophosphorous acid alkaline earth metal salts such as calcium hypophosphite. Phosphates include, but the present invention is not limited to such embodiments. Each of these phosphorus compounds may be used alone, or two or more kinds may be used in combination. Among the phosphorus compounds, hypophosphorous acid alkali metal salts and hypophosphorous acids are used from the viewpoint of promoting the precipitation of nickel on the surface of the base material and forming a black plating film having excellent blackness, water repellency and slidability. Alkali phosphate earth metal salts are preferred, hypophosphorous acid alkali metal salts are more preferred, and sodium hypophosphate is even more preferred.

The content of the phosphorus compound in the plating solution for forming a nickel plating film is preferably 1 g / L or more, more preferably 3 g / L or more, and further preferably 5 g / L from the viewpoint of efficiently precipitating nickel on the surface of the base material. From the viewpoint of improving the adhesion between the base material and the black plating film and forming a black plating film having excellent blackness, water repellency and slidability, it is preferably 25 g / L or less, more preferably 20 g. / L or less, more preferably 15 g / L or less.

The specific carboxylic acid (salt) is at least one carboxylic acid selected from the group consisting of monocarboxylic acid, polycarboxylic acid, oxycarboxylic acid and salts thereof. The specific carboxylic acid (salt) is a component for homogenizing nickel precipitated on the surface of the base material to form a black plating film having excellent blackness, water repellency and slidability. Examples of the specific carboxylic acid (salt) include oxalic acid, formic acid, acetic acid, propionic acid, butyric acid, malonic acid, gluconic acid, maleic acid, and alkali metal salts or ammonium salts thereof. , It is not limited to such an example. These specific carboxylic acids (salts) may be used alone or in combination of two or more. Among the specific carboxylic acids (salts), oxalic acid, formic acid, and acetic acid are used from the viewpoint of homogenizing the nickel precipitated on the surface of the substrate and forming a black plating film having excellent blackness, water repellency, and slidability. , Propionic acid, butyric acid, malonic acid, maleic acid, and at least one carboxylic acid selected from the group consisting of alkali metal salts or ammonium salts thereof, preferably oxalic acid, propionic acid, malonic acid, malonic acid, maleic acid. , And at least one carboxylic acid selected from the group consisting of alkali metal salts or ammonium salts thereof, and oxalic acid or its alkali metal salt or ammonium salt is even more preferable.

The content of the specific carboxylic acid (salt) in the plating solution for forming the nickel plating film homogenizes the nickel precipitated on the surface of the base material and forms a black plating film having excellent blackness, water repellency and slidability. From the viewpoint, it is preferably 20 g / L or more, more preferably 25 g / L or more, still more preferably 30 g / L or more, and preferably 50 g / L or less from the viewpoint of enhancing the adhesion between the base material and the black plating film. It is more preferably 45 g / L or less, still more preferably 40 g / L or less.

In the plating solution for forming a nickel plating film, for example, a nickel compound, a phosphorus compound, a specific carboxylic acid (salt), and an additive used as necessary are mixed with water so as to have a predetermined concentration, and each component is made uniform. It can be easily prepared by dissolving or dispersing in water so as to have a composition.

Examples of the additive include, for example, a precipitation accelerator, a stabilizer, a surfactant, and the like, but the present invention is not limited to these examples. Since the amount of the additive varies depending on the type of the additive, it cannot be unconditionally determined. Therefore, it is preferable to appropriately determine the amount according to the type of the additive.

The precipitation accelerator is a component that promotes the precipitation of nickel on the surface of the substrate. Examples of the precipitation accelerator include thiols, sulfides, alkylene sulfides, disulfides, thioaldehydes, thioketones, thiocyanates, thiocyanates, thioureas, thiosulfates, thiosulfates, and the like. It is not limited to illustrations only. These precipitation accelerators may be used alone or in combination of two or more. Among these, thiols, sulfides, alkylene thrifides, disulfides, thioaldehydes, thioketones and thiocyanates from the viewpoint of promoting the precipitation of nickel and forming a black plating film having excellent blackness, water repellency and slidability. At least one precipitation accelerator selected from the group consisting of acids is preferable, at least one precipitation accelerator selected from the group consisting of thiols, sulfides, alkyleneslides and disulfides is more preferable, and thiols are even more preferable.

The content of the precipitation accelerator in the plating solution for forming a nickel plating film is preferably 0.001 g / L or more, more preferably 0.003 g / L or more, still more preferably 0.005 g, from the viewpoint of promoting the precipitation of nickel. / L or more, preferably 0.05 g / L or less, more preferably 0.03 g / L or less, still more preferably 0.01 g / L or less, from the viewpoint of homogenizing the nickel precipitated on the surface of the substrate. is there.

The stabilizer is a component for stably precipitating nickel on the surface of the substrate. Examples of the stabilizer include bismuth nitrate and bismuth acetate, but the present invention is not limited to these examples. Each of these stabilizers may be used alone or in combination.

The content of the stabilizer in the plating solution for forming a nickel plating film is preferably 0.01 g / L or more, more preferably 0.03 g / L or more, from the viewpoint of stably precipitating nickel on the surface of the substrate. It is more preferably 0.05 g / L or more, and from the viewpoint of homogenizing the nickel precipitated on the surface of the substrate, it is preferably 0.5 g / L or less, more preferably 0.3 g / L or less, still more preferably 0. .1 g / L or less.

Examples of the surfactant include anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants and the like, but the present invention is not limited to these examples. Each of these surfactants may be used alone or in combination of two or more. The surfactant is used in an appropriate amount in the plating solution for forming a nickel plating film.

As a specific method for forming a nickel plating film on the surface of the base material using the plating solution for forming a nickel plating film, for example, in the plating solution for forming a nickel plating film having a liquid temperature of 30 to 95 ° C. An electroless plating method in which a base material is immersed in a base material can be mentioned.

The thickness of the nickel plating film formed on the surface of the metal base material is preferably 3 μm or more, more preferably 5 μm, from the viewpoint of interposing between the base material and the black plating film to improve the adhesion between the two. As described above, the thickness is preferably 30 μm or less, more preferably 20 μm or less, from the viewpoint of interposing between the base material and the black plating film to enhance the adhesion between the two. The thickness of the nickel plating film can be easily adjusted by adjusting the plating conditions such as the temperature of the plating solution for forming the nickel plating film and the plating time.

As described above, a nickel plating film containing nickel and phosphorus is formed on the surface of the base material.

The content of nickel in the nickel plating film is preferably 60% by mass or more, more preferably 65% by mass or more, from the viewpoint of enhancing the adhesion between the base material and the black plating film. From the viewpoint of enhancing the adhesion, it is preferably 85% by mass or less, more preferably 80% by mass or less, and further preferably 75% by mass or less.

The phosphorus content in the nickel plating film is preferably 0.3% by mass or more, more preferably 0.5% by mass or more, still more preferably 1% by mass, from the viewpoint of enhancing the adhesion between the base material and the black plating film. From the viewpoint of enhancing the adhesion between the base material and the black plating film, the content is preferably 4% by mass or less, more preferably 3% by mass or less.

The balance of the component in the nickel plating film is oxygen, but the nickel plating film may contain impurities. Examples of the impurities include carbon, iron and the like, but the present invention is not limited to these examples. Further, the nickel plating film may contain other elements as long as the object of the present invention is not impaired.

The content of each component in the nickel plating film is contained in the nickel plating film forming plating solution by adjusting the amount of nickel compound, phosphorus compound, precipitation accelerator added as necessary, stabilizer, surfactant, etc. It can be adjusted by adjusting the content of each component to a predetermined value.

As described above, a nickel plating film can be obtained.
Next, a black plating film is formed on the nickel plating film. When forming a black plating film, a plating solution for forming a black plating film is used.

As the plating solution for forming a black plating film, a plating solution for forming a black plating film containing a nickel compound, a phosphorus compound, a specific carboxylic acid (salt) and fluororesin particles is used.

Examples of the nickel compound used in the plating solution for forming a black plating film include the same nickel compounds as those used in the plating solution for forming a nickel plating film. The content of the nickel compound in the plating solution for forming a black plating film is preferably 3 g / L or more, more preferably 5 g / L or more, still more preferably 10 g / L or more, from the viewpoint of improving the adhesion to the nickel plating film. From the viewpoint of improving the adhesion to the nickel plating film, it is preferably 30 g / L or less, more preferably 25 g / L or less, and further preferably 20 g / L or less.

Examples of the phosphorus compound used in the plating solution for forming a black plating film include the same phosphorus compounds as those used in the plating solution for forming a nickel plating film. The content of the phosphorus compound in the plating solution for forming a black plating film is preferably 1 g / L or more, more preferably 3 g / L or more, still more preferably 5 g / L or more, from the viewpoint of improving the adhesion to the nickel plating film. From the viewpoint of improving the adhesion to the nickel plating film, it is preferably 25 g / L or less, more preferably 20 g / L or less, and further preferably 15 g / L or less.

As the specific carboxylic acid (salt) used in the plating solution for forming a black plating film, the same carboxylic acid (salt) as the specific carboxylic acid (salt) used in the plating solution for forming a nickel plating film can be exemplified. The specific carboxylic acid (salt) is a component for homogenizing nickel precipitated on the surface of the base material to form a black plating film having excellent blackness, water repellency and slidability. Examples of the specific carboxylic acid (salt) include oxalic acid, formic acid, acetic acid, propionic acid, butyric acid, malonic acid, gluconic acid, maleic acid, and alkali metal salts or ammonium salts thereof. , It is not limited to such an example. These specific carboxylic acids (salts) may be used alone or in combination of two or more. Among the specific carboxylic acids (salts), oxalic acid, formic acid, and acetic acid are used from the viewpoint of homogenizing the nickel precipitated on the surface of the substrate and forming a black plating film having excellent blackness, water repellency, and slidability. , Propionic acid, butyric acid, malonic acid, maleic acid, and at least one carboxylic acid selected from the group consisting of alkali metal salts or ammonium salts thereof, preferably oxalic acid, propionic acid, malonic acid, malonic acid, maleic acid. , And at least one carboxylic acid selected from the group consisting of alkali metal salts or ammonium salts thereof, and oxalic acid or its alkali metal salt or ammonium salt is even more preferable.

The content of the specific carboxylic acid (salt) in the plating solution for forming the black plating film is preferably 20 g / L or more, more preferably 25 g / L or more, still more preferably 25 g / L or more, from the viewpoint of improving the adhesion to the nickel plating film. It is 30 g / L or more, and is preferably 50 g / L or less, more preferably 45 g / L or less, and further preferably 40 g / L or less from the viewpoint of improving the adhesion to the nickel plating film.

Examples of the fluororesin constituting the fluororesin particles include polytetrafluoroethylene, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and tetrafluoroethylene-perfluoroalkyl vinyl ether. Examples thereof include polymers, tetrafluoroethylene-ethylene copolymers, polyvinylidene fluoride, polychlorotrifluoroethylene, chlorotrifluoroethylene-ethylene copolymers, etc., but the present invention is limited to these examples only. is not. Each of these fluororesins may be used alone, or two or more types may be used in combination. Among these fluororesins, polytetrafluoroethylene is preferable from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability.

The average particle size of the fluororesin particles is preferably 0.1 μm or more, more preferably 0.2 μm, from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. From the viewpoint of improving slidability, it is preferably 3 μm or less, more preferably 2 μm or less, and further preferably 1 μm or less. The average particle size of the fluororesin particles means the particle size when the volume-based particle size distribution is measured by a laser diffraction method and the cumulative volume frequency is 50%.

The surface of the fluororesin particles may be covered with a surfactant, if necessary, from the viewpoint of improving the dispersibility of the fluororesin particles in the plating solution for forming a black plating film. Examples of the surfactant include anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants and the like, but the present invention is not limited to these examples. Each of these surfactants may be used alone or in combination of two or more.

The fluororesin particles are preferably used as a dispersion liquid that has been previously dispersed in a solvent such as water, for example, from the viewpoint of improving the dispersibility of the fluororesin particles in the plating solution for forming a black plating film.

The plating solution for forming a black plating film can be easily prepared by adding a nickel compound, a phosphorus compound, a specific carboxylic acid (salt) and fluororesin particles to water and dispersing them in water so as to have a uniform composition. it can. As the plating solution for forming the black plating film, the plating solution for forming the nickel plating film used for forming the nickel plating film may be used, and the plating solution for forming the nickel plating film after forming the nickel plating film may be used. You may use it.

If necessary, an appropriate amount of a precipitation accelerator, a stabilizer, a surfactant, or the like may be added to the plating solution for forming a black plating film.

As the precipitation accelerator used in the plating solution for forming a black plating film, the same precipitation accelerator used in the plating solution for forming a nickel plating film can be exemplified. Among the precipitation accelerators, thiols, sulfides, alkylene sulfides, disulfides, thioaldehydes, and thioketones are used from the viewpoint of promoting the precipitation of nickel and forming a black plating film having excellent blackness, water repellency, and slidability. And at least one precipitation accelerator selected from the group consisting of thiosian acid is preferred, at least one precipitation accelerator selected from the group consisting of thiols, sulfides, alkyleneslides and disulfides is more preferred, and thiols are even more preferred. preferable.

The content of the precipitation accelerator in the plating solution for forming a black plating film is preferably 0.001 g / L or more, more preferably 0.003 g / L or more, still more preferably 0.005 g, from the viewpoint of promoting the precipitation of nickel. It is preferably 0.05 g / L or less, more preferably 0.03 g / L or less, still more preferably 0. L or more, from the viewpoint of homogenizing the black plating film forming film deposited on the nickel plating film. It is 01 g / L or less.

As the stabilizer used in the plating solution for forming a black plating film, the same ones as the precipitation accelerator used in the plating solution for forming a nickel plating film can be exemplified. The content of the stabilizer in the plating solution for forming the black plating film is preferably 0.01 g / L or more, more preferably 0., from the viewpoint of stably forming the film for forming the black plating film on the nickel plating film. It is 03 g / L or more, more preferably 0.05 g / L or more, and is preferably 0.5 g from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. / L or less, more preferably 0.3 g / L or less, still more preferably 0.1 g / L or less.

Examples of the surfactant used in the plating solution for forming a black plating film include anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, and the like. It is not limited to only. Each of these surfactants may be used alone or in combination of two or more. The surfactant is used in an appropriate amount in the plating solution for forming a black plating film.

As a specific method for forming the black plating film forming film on the surface of the nickel plating film, for example, the nickel plating film is formed in the black plating film forming plating solution having a liquid temperature of 30 to 95 ° C. Examples thereof include an electroless plating method in which an existing base material is immersed.

The thickness of the black plating film forming film formed on the surface of the nickel plating film is preferable from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. Is 3 μm or more, more preferably 5 μm or more, and is preferably 30 μm or less, more preferably 20 μm or less, from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. Is. The thickness of the black plating film forming film can be easily adjusted by adjusting the plating conditions such as the temperature of the black plating film forming plating solution and the plating time.

As described above, a black plating film forming film is formed on the surface of the nickel plating film.

The nickel content in the black plating film forming film is preferably 60% by mass or more, more preferably from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. Is 65% by mass or more, preferably 85% by mass or less, more preferably 80% by mass or less, from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. , More preferably 75% by mass or less.

The phosphorus content in the black plating film forming film is preferably 0.3% by mass or more from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. It is more preferably 0.5% by mass or more, further preferably 1% by mass or more, and preferably 4% by mass or less, more preferably 3% by mass or less, from the viewpoint of enhancing the adhesion between the base material and the black plating film. is there.

The content of fluorine in the black plating film forming film is preferably 0.3% by mass or more from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. It is more preferably 0.5% by mass or more, still more preferably 1% by mass or more, and is preferably from the viewpoint of forming a black plating film which is excellent in blackness and water repellency and also excellent in slidability. It is 3.5% by mass or less, more preferably 3% by mass or less, still more preferably 2.5% by mass or less.

The rest of the component in the black plating film forming film is oxygen, but the black plating film forming film may contain impurities. Examples of the impurities include carbon, iron and the like, but the present invention is not limited to these examples. Further, the coating film for forming a black plating film may contain other elements as long as the object of the present invention is not impaired.

The content of each component in the black plating film forming film is adjusted by adjusting the amount of nickel compound, phosphorus compound, specific carboxylic acid (salt), precipitation accelerator added as necessary, stabilizer, surfactant, etc. It can be adjusted by adjusting the content of each component contained in the plating solution for forming a black plating film to a predetermined value.

Next, the black plating film is formed by blackening the black plating film forming film formed on the surface of the nickel plating film.

When blackening the coating for forming a black plating film, a plating coating blackening treatment liquid is used. Examples of the plating film blackening treatment solution include a plating film blackening treatment solution containing thiourea, alkylenediamine and an aromatic sulfonate. The plating film blackening treatment liquid can be easily prepared, for example, by dissolving thiourea, alkylenediamine and aromatic sulfonate in water.

The content of thiourea in the blackening treatment liquid for the plating film is preferably 2 g / L or more, more preferably 2.5 g / L or more, still more preferably 3 g / L or more, from the viewpoint of increasing the blackness of the black plating film. From the viewpoint of enhancing the corrosion resistance of the black plating film, it is preferably 15 g / L or less, more preferably 10 g / L or less, and further preferably 7 g / L or less.

The alkylene diamine used in the plating film blackening treatment liquid is a component that forms a black plating film that is excellent in blackness and water repellency and also has excellent slidability. Examples of the alkylenediamine include alkylenediamine having an alkylene group having 2 to 6 carbon atoms such as ethylenediamine, propylenediamine, and hexamethylenediamine, but the present invention is not limited to these examples. .. Each of these alkylene diamines may be used alone, or two or more kinds may be used in combination. Among the alkylenediamines, ethylenediamine, propylenediamine and hexamethylenediamine are preferable, and ethylenediamine is more preferable, from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability.

The content of alkylenediamine in the blackening treatment liquid for the plating film is preferably 3 g / L or more, from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. It is preferably 5 g / L or more, more preferably 10 g / L or more, and is preferably 40 g / L from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. Below, it is more preferably 35 g / L or less, still more preferably 30 g / L or less.

The aromatic sulfonate used in the plating film blackening treatment liquid is a component that forms a black plating film that is excellent in blackness and water repellency and also has excellent slidability. Examples of the aromatic sulfonate include toluene sulfonate, alkylbenzene sulfonate, and the like, but the present invention is not limited to these examples. Each of these aromatic sulfonates may be used alone or in combination.

Examples of the toluene sulfonate include, for example, an alkali metal salt of toluene sulfonic acid such as sodium toluene sulfonate and potassium toluene sulfonate, but the present invention is not limited to such examples.

Examples of the alkylbenzene sulfonate include sodium ethylbenzenesulfonate, potassium ethylbenzenesulfonate, sodium propylbenzenesulfonate, potassium propylbenzenesulfonate, sodium butylbenzenesulfonate, potassium butylbenzenesulfonate, sodium hexylbenzenesulfonate, and hexyl. Potassium benzenesulfonate, sodium octylbenzenesulfonate, potassium octylbenzenesulfonate, sodium nonylbenzenesulfonate, potassium nonylbenzenesulfonate, sodium decylbenzenesulfonate, potassium decylbenzenesulfonate, sodium dodecylbenzenesulfonate, dodecylbenzenesulfone Alkyl groups such as potassium acid, sodium tetradecylbenzenesulfonate, potassium tetradecylbenzenesulfonic acid, sodium octadecylbenzenesulfonate, and potassium octadecylbenzenesulfonate have 1 to 24 carbon atoms, preferably 2 to 20, more preferably 2. Examples thereof include alkylbenzene sulfonates of ~ 18, but the present invention is not limited to these examples. These alkylbenzene sulfonates may be used alone or in combination of two or more.

Among aromatic sulfonates, toluene sulfonates and alkylbenzene sulfonates having an alkyl group having 1 to 24 carbon atoms are formed from the viewpoint of forming a black plating film having excellent blackness, water repellency and slidability. The toluene sulfonate and the alkylbenzene sulfonate having an alkyl group having 2 to 20 carbon atoms are more preferable, and the toluene sulfonate and an alkylbenzene sulfonic acid alkali metal salt having an alkyl group having 2 to 18 carbon atoms are more preferable. More preferably, the toluene sulfonate and the alkylbenzene sulfonic acid alkali metal salt having 8 to 18 carbon atoms in the alkyl group are even more preferable. Examples of the salt include alkali metal salts. Examples of the alkali metal include lithium, sodium and potassium, but sodium and potassium are preferable from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. Specific examples of aromatic sulfonates suitable from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability include sodium toluene sulfonate and sodium nonylbenzene sulfonate. Examples thereof include sodium dodecylbenzenesulfonate and potassium dodecylbenzenesulfonate, and these aromatic sulfonates may be used alone or in combination of two or more. All of these aromatic sulfonates can be suitably used from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability.

The content of the aromatic sulfonate in the plating film blackening treatment liquid is preferably 3 g / L from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. As described above, it is more preferably 5 g / L or more, further preferably 10 g / L or more, and it is preferable from the viewpoint of forming a black plating film which is excellent in blackness and water repellency and also excellent in slidability. It is 40 g / L or less, more preferably 35 g / L or less, still more preferably 30 g / L or less.

The black plating film can be obtained, for example, by immersing a base material on which a black plating film forming film is formed in a plating film blackening treatment liquid. At that time, the liquid temperature of the plating film blackening treatment liquid is usually about 20 to 60 ° C. The time for immersing the metal base material on which the black plating film forming film is formed in the plating film blackening treatment liquid varies depending on the thickness of the black plating film to be formed, and therefore cannot be unconditionally determined. , It is preferable to determine appropriately according to the thickness of the black plating film.

As described above, a black plating film is formed in which the black plating film forming film is blackened. The entire black plating film forming film may be blackened to form a black plating film, or only the surface layer of the black plating film forming film may be blackened to form a black plating film.

The content of nickel in the black plating film is preferably 60% by mass or more, more preferably 65% by mass, from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. % Or more, preferably 85% by mass or less, more preferably 80% by mass or less, still more preferably, from the viewpoint of forming a black plating film which is excellent in blackness and water repellency and also excellent in slidability. Is 75% by mass or less.

The phosphorus content in the black plating film is preferably 0.3% by mass or more, more preferably 0.3% by mass or more, from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. It is 0.5% by mass or more, more preferably 1% by mass or more, and is preferably 4% by mass from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. Hereinafter, it is more preferably 3% by mass or less.

The content of fluorine in the black plating film is preferably 0.3% by mass or more, more preferably 0.3% by mass or more, from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. It is 0.5% by mass or more, more preferably 1% by mass or more, and is preferably 3.5 from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. It is mass% or less, more preferably 3 mass% or less, still more preferably 2.5 mass% or less.

The sulfur content in the black plating film is preferably 0.5% by mass or more, more preferably 0.5% by mass or more, from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. It is preferably 1% by mass or more, more preferably 2% by mass or more, and preferably 15% by mass or less from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. It is more preferably 10% by mass or less, still more preferably 8% by mass or less.

The balance of the component in the black plating film is oxygen, but the black plating film may contain impurities. Examples of the impurities include carbon, iron and the like. Further, the black plating film may contain other elements as long as the object of the present invention is not impaired.

The thickness of the black plating film is preferably 0.3 μm or more, more preferably 0.5 μm or more, from the viewpoint of forming a black plating film having excellent blackness and water repellency and also excellent slidability. It is preferably 3 μm or less, more preferably 2 μm or less, from the viewpoint of forming a black plating film which is excellent in blackness and water repellency and also excellent in slidability.

As described above, since the black plating film of the present invention has the above-mentioned structure, the L value indicating the blackness of the black plating film is conventionally at least about 5 to 10, whereas the black plating film of the present invention has the above-mentioned structure. Since the L value indicating the blackness of the black plating film is 3 or less, the blackness is very excellent. The L value is a value measured based on the method described in the following examples. Further, since the black plating film of the present invention has the above-mentioned structure, it is also excellent in water repellency and slidability.

The laminated plating film of the present invention is excellent in blackness, water repellency, and slidability because the black plating film is formed on the nickel plating film containing nickel and phosphorus.

Therefore, the black plating film and the laminated plating film of the present invention can be suitably used for, for example, optical members, medical devices, and the like that require blackness, water repellency, and slidability.

Next, the black plating film and the laminated plating film of the present invention will be described in more detail based on Examples, but the present invention is not limited to such Examples.

Example 1
1. 1. Pretreatment (1) Degreasing treatment A steel plate (SS400 rolled steel plate specified in JIS G3101, length: 10 cm, width: 10 cm square, plate thickness: 1.5 mm) is used as a base material, and contains sodium hydroxide and a surfactant. The steel sheet was degreased by immersing the steel sheet in an alkaline degreasing solution.

(2) Acid Treatment The steel sheet that had been degreased as described above was immersed in an acidic treatment liquid consisting of hydrochloric acid to perform acid treatment on the steel sheet.

(3) Palladium treatment In order to improve the adhesion between the steel sheet and the plating film, the steel sheet subjected to the acid treatment is immersed in a palladium-containing treatment liquid containing hydrochloric acid and palladium chloride to immerse the steel sheet in the steel sheet. It was treated with palladium.

Since the necessity of the above operation differs depending on the type of the base material used, the operation is performed as necessary according to the type of the base material.

2. 2. Formation of nickel-plated film The acid-treated steel sheet was coated with nickel sulfate 15 g / L, oxalic acid 35 g / L, thiol 0.01 g / L, bismuth nitrate 0.1 g / L and sodium hypophosphite 10 g / L. A nickel plating film having a thickness of 10 μm was formed on the steel sheet by immersing it in a plating solution for forming a nickel plating film at 90 ° C.

The elemental analysis of the nickel plating film obtained above was examined by an energy dispersive X-ray analyzer [manufactured by AMETEK, Inc., product number: Element]. As a result, the nickel plating film has 71.6% by mass of nickel, 2.1% by mass of phosphorus, 6.5% by mass of sulfur, 1.8% by mass of carbon, 1.9% by mass of iron and 18.2% by mass of oxygen. Was confirmed to be included.

3. 3. Formation of film for forming black plating film Nickel sulfate 15 g / L, oxalic acid 35 g / L, thiol 0.01 g / L, bismuth nitrate 0.1 g / L, sodium hypophosphite 10 g / L and fluororesin (polytetrafluoro) By immersing the steel sheet on which the nickel plating film is formed in a water dispersion for forming a black plating film at 90 ° C. containing 65 g / L of ethylene) particles (average particle size: 200 nm) for 20 minutes, the thickness is increased on the steel sheet. A film for forming a black plating film having a size of 10 μm was formed.

The elemental analysis of the black plating film forming film obtained above was examined by an energy dispersive X-ray analyzer [manufactured by AMETEK, Inc., product number: Element]. As a result, the film for forming the black plating film had nickel 70.3% by mass, fluorine 2.2% by mass, phosphorus 2.1% by mass, sulfur 5.5% by mass, carbon 1.2% by mass, and iron 2. It was confirmed that 2% by mass and 18.7% by mass of oxygen were contained.

4. Formation of black plating film Next, the steel sheet on which the black plating film forming film obtained above is formed contains 5.5 g / L of thiourea, 20 g / L of ethylenediamine, and 10 g / L of sodium dodecylbenzenesulfonate 40. By immersing the steel sheet on which the black plating film forming film is formed in the plating film blackening treatment liquid at ℃ for 20 minutes, the black plating film forming film is blackened and the black plating film having a thickness of 1.5 μm is formed. Was formed.

By performing the above operation, a steel sheet on which a laminated plating film having a black plating film was formed was obtained. The elemental analysis of the black plating film obtained above was examined by an energy dispersive X-ray analyzer [manufactured by AMETEK, Inc., product number: Element]. As a result, the black plating film had nickel 70.3% by mass, fluorine 2.2% by mass, phosphorus 2.1% by mass, sulfur 5.5% by mass, carbon 1.2% by mass, and iron 2.2% by mass. And it was confirmed that 18.7% by mass of oxygen was contained.

The steel sheet having the laminated plating film obtained above was cut, and the cross section thereof was observed with a scanning electron microscope [manufactured by Hitachi High-Technologies Corporation, product number: SU3500]. The result is shown in FIG. FIG. 1 is a scanning electron micrograph of a cross section of the laminated plating film having the black plating film obtained in Example 1.

In FIG. 1, 1 is a steel plate of a base material, 2 is a nickel plating film, 3 is a black plating film forming film in which a black plating film is not formed, and 4 is a black plating film.

In the laminated plating film having the black plating film obtained above, as shown in FIG. 1, a nickel plating film 2 is formed on the base material 1, and a black plating film forming film 3 is formed on the nickel plating film 2. Is formed, and it can be seen that the black plating film 4 is formed as the outermost surface layer on the black plating film forming film 3.

Next, as the physical properties of the steel sheet having the black plating film, the water repellency, slidability and blackness of the black plating film were investigated based on the following methods. The results are shown in Table 1.

[Water repellency]
1.0 μL of pure water (liquid temperature: 25 ° C.) is dropped on the surface of the black plating film, and the contact angle of water on the surface of the black plating film is measured by a contact angle meter [Kyowa Interface Science Co., Ltd., product number: DM-301. ], And the water repellency was evaluated based on the following evaluation criteria.
(Evaluation criteria)
A: Water contact angle is 100 ° or more B: Water contact angle is 90 ° or more and less than 100 ° C: Water contact angle is 80 ° or more and less than 90 ° D: Water contact angle is 70 ° or more and less than 80 ° E : Water contact angle is less than 70 °

[Sliding]
The slidability was evaluated using a slidability test device (manufactured by CSEM, trade name: TRIBOMETER PIN ON DISK). A chrome steel ball (hardness: 300 HBM) having a diameter of 6 mm was placed on the surface of the black plating film, and the chrome steel ball was moved at a constant speed of 10 mm / sec while applying a load of 1 N in the vertical direction to the chrome steel ball. The dynamic friction coefficient at that time was measured, and the slidability was evaluated based on the following evaluation criteria.
(Evaluation criteria)
A: Dynamic friction coefficient is less than 0.2 μk B: Dynamic friction coefficient is 0.2 μk or more and less than 0.3 μk C: Dynamic friction coefficient is 0.3 μk or more and less than 0.4 μk D: Dynamic friction coefficient is 0.4 μk or more and less than 0.5 μk E: Dynamic friction coefficient is 0.5 μk or more

[Blackness]
The blackness of the black plating film is measured by measuring the L value (brightness) of the cross section of the black plating film at wavelengths of 400 nm, 450 nm and 500 nm using a spectrocolorimeter [manufactured by Nippon Denshoku Kogyo Co., Ltd., product number: SD7000]. The water repellency at each wavelength was evaluated based on the following evaluation criteria.
(Evaluation criteria)
A: L value is less than 2.8 B: L value is 2.8 or more and less than 2.9 C: L value is 2.9 or more and less than 3.0 D: L value is 3.0 or more and less than 3.1 E: L value is 3.1 or more

Example 2
In Example 1, the same operation as in Example 1 is performed except that the composition of the plating solution for forming the black plating film is changed, and the time required for plating and the time for blackening the black plating film forming film are changed. As a result, a nickel plating film having a thickness of 8 μm is formed on the steel plate, a black plating film forming film having a thickness of 15 μm is formed on the nickel plating film, and the black plating film forming film is blackened. A laminated plating film having a black plating film with a thickness of 1.2 μm was obtained on the surface layer. The elemental analysis of the black plating film obtained above was carried out in the same manner as in Example 1. As a result, the black plating film has 68.5% by mass of nickel, 1.2% by mass of fluorine, 2.8% by mass of phosphorus, 6.8% by mass of sulfur, 1.2% by mass of carbon, and 2.2% by mass of iron. And it was confirmed that 18.7% by mass of oxygen was contained.

Next, as the physical properties of the steel sheet having the black plating film, the water repellency, slidability and blackness of the black plating film were examined in the same manner as in Example 1. The results are shown in Table 1.

Example 3
In Example 1, the same operation as in Example 1 is performed except that the composition of the plating solution for forming the black plating film is changed, and the time required for plating and the time for blackening the black plating film forming film are changed. As a result, a nickel plating film having a thickness of 8 μm is formed on the steel plate, a black plating film forming film having a thickness of 15 μm is formed on the nickel plating film, and the black plating film forming film is blackened. A laminated plating film having a black plating film with a thickness of 0.8 μm was obtained on the surface layer. The elemental analysis of the black plating film obtained above was carried out in the same manner as in Example 1. As a result, the black plating film had nickel 72.4% by mass, fluorine 2.3% by mass, phosphorus 1.6% by mass, sulfur 4.2% by mass, carbon 1.2% by mass, and iron 2.2% by mass. And it was confirmed that 18.7% by mass of oxygen was contained.

Next, as the physical properties of the steel sheet having the black plating film, the water repellency, slidability and blackness of the black plating film were examined in the same manner as in Example 1. The results are shown in Table 1.

Example 4
By performing the same operation as in Example 1 except that the composition of the plating solution for forming the nickel plating film was changed in Example 1, a nickel plating film having a thickness of 10 μm was formed on the steel sheet. By forming a black plating film forming film having a thickness of 1.5 μm on the nickel plating film and blackening the black plating film forming film, a black plating film having a thickness of 1.5 μm is formed on the surface layer. A laminated plating film having was obtained. The elemental analysis of the black plating film obtained above was carried out in the same manner as in Example 1. As a result, the nickel-plated coating had nickel 62.3% by mass, phosphorus 1.6% by mass, sulfur 4.5% by mass, carbon 1.8% by mass, iron 1.9% by mass, and oxygen 18.2% by mass. Was confirmed to be included.

Next, as the physical properties of the steel sheet having the black plating film, the water repellency, slidability and blackness of the black plating film were examined in the same manner as in Example 1. The results are shown in Table 1.

Example 5
By performing the same operation as in Example 1 except that the composition of the plating solution for forming the nickel plating film was changed in Example 1, a nickel plating film having a thickness of 10 μm was formed on the steel sheet. By forming a black plating film forming film having a thickness of 1.5 μm on the nickel plating film and blackening the black plating film forming film, a black plating film having a thickness of 1.5 μm is formed on the surface layer. A laminated plating film having was obtained. The elemental analysis of the black plating film obtained above was carried out in the same manner as in Example 1. As a result, the nickel plating film has 73.1% by mass of nickel, 1.3% by mass of phosphorus, 4.8% by mass of sulfur, 1.6% by mass of carbon, 1.5% by mass of iron, and 18.1% by mass of oxygen. Was confirmed to be included.

Next, as the physical properties of the steel sheet having the black plating film, the water repellency, slidability and blackness of the black plating film were examined in the same manner as in Example 1. The results are shown in Table 1.

Example 6
By performing the same operation as in Example 1 except that the composition of the plating solution for forming the black plating film was changed in Example 1, a nickel plating film having a thickness of 10 μm was formed on the steel sheet. By forming a black plating film forming film having a thickness of 1.5 μm on the nickel plating film and blackening the black plating film forming film, a black plating film having a thickness of 1.5 μm is formed on the surface layer. A laminated plating film having was obtained. The elemental analysis of the black plating film obtained above was carried out in the same manner as in Example 1. As a result, the black plating film has 72.3% by mass of nickel, 2.1% by mass of fluorine, 2.0% by mass of phosphorus, 5.2% by mass of sulfur, 1.4% by mass of carbon, and 2.0% by mass of iron. And it was confirmed that 18.7% by mass of oxygen was contained.

Next, as the physical properties of the steel sheet having the black plating film, the water repellency, slidability and blackness of the black plating film were examined in the same manner as in Example 1. The results are shown in Table 1.

Example 7
By performing the same operation as in Example 1 except that the composition of the plating solution for forming the black plating film was changed in Example 1, a nickel plating film having a thickness of 10 μm was formed on the steel sheet. By forming a black plating film forming film having a thickness of 1.5 μm on the nickel plating film and blackening the black plating film forming film, a black plating film having a thickness of 1.5 μm is formed on the surface layer. A laminated plating film having was obtained. The elemental analysis of the black plating film obtained above was carried out in the same manner as in Example 1. As a result, the black plating film had nickel 70.3% by mass, fluorine 2.2% by mass, phosphorus 2.1% by mass, sulfur 5.5% by mass, carbon 1.2% by mass, and iron 2.2% by mass. And it was confirmed that 18.7% by mass of oxygen was contained.

Next, as the physical properties of the steel sheet having the black plating film, the water repellency, slidability and blackness of the black plating film were examined in the same manner as in Example 1. The results are shown in Table 1.

Example 8
By performing the same operation as in Example 1 except that the composition of the plating solution for forming the black plating film was changed in Example 1, a nickel plating film having a thickness of 10 μm was formed on the steel sheet. By forming a black plating film forming film having a thickness of 1.5 μm on the nickel plating film and blackening the black plating film forming film, a black plating film having a thickness of 1.5 μm is formed on the surface layer. A laminated plating film having was obtained. The elemental analysis of the black plating film obtained above was carried out in the same manner as in Example 1. As a result, the black plating film had nickel 70.3% by mass, fluorine 2.2% by mass, phosphorus 2.1% by mass, sulfur 5.5% by mass, carbon 1.2% by mass, and iron 2.2% by mass. And it was confirmed that 18.7% by mass of oxygen was contained.

Next, as the physical properties of the steel sheet having the black plating film, the water repellency, slidability and blackness of the black plating film were examined in the same manner as in Example 1. The results are shown in Table 1.

Example 9
By performing the same operation as in Example 1 except that the composition of the plating solution for forming the black plating film was changed in Example 1, a nickel plating film having a thickness of 10 μm was formed on the steel sheet. By forming a black plating film forming film having a thickness of 1.5 μm on the nickel plating film and blackening the black plating film forming film, a black plating film having a thickness of 1.5 μm is formed on the surface layer. A laminated plating film having was obtained. The elemental analysis of the black plating film obtained above was carried out in the same manner as in Example 1. As a result, the black plating film had nickel 70.3% by mass, fluorine 2.2% by mass, phosphorus 2.1% by mass, sulfur 5.5% by mass, carbon 1.2% by mass, and iron 2.2% by mass. And it was confirmed that 18.7% by mass of oxygen was contained.

Next, as the physical properties of the steel sheet having the black plating film, the water repellency, slidability and blackness of the black plating film were examined in the same manner as in Example 1. The results are shown in Table 1.

Example 10
By performing the same operation as in Example 1 except that the composition of the plating solution for forming the black plating film was changed in Example 1, a nickel plating film having a thickness of 10 μm was formed on the steel sheet. By forming a black plating film forming film having a thickness of 1.5 μm on the nickel plating film and blackening the black plating film forming film, a black plating film having a thickness of 1.5 μm is formed on the surface layer. A laminated plating film having was obtained. The elemental analysis of the black plating film obtained above was carried out in the same manner as in Example 1. As a result, the black plating film had nickel 70.3% by mass, fluorine 2.2% by mass, phosphorus 2.1% by mass, sulfur 5.5% by mass, carbon 1.2% by mass, and iron 2.2% by mass. And it was confirmed that 18.7% by mass of oxygen was contained.

Next, as the physical properties of the steel sheet having the black plating film, the water repellency, slidability and blackness of the black plating film were examined in the same manner as in Example 1. The results are shown in Table 1.

Example 11
By performing the same operation as in Example 1 except that the composition of the plating solution for forming the black plating film was changed in Example 1, a nickel plating film having a thickness of 10 μm was formed on the steel sheet. By forming a black plating film forming film having a thickness of 1.5 μm on the nickel plating film and blackening the black plating film forming film, a black plating film having a thickness of 1.5 μm is formed on the surface layer. A laminated plating film having was obtained. The elemental analysis of the black plating film obtained above was carried out in the same manner as in Example 1. As a result, the black plating film had nickel 70.3% by mass, fluorine 2.2% by mass, phosphorus 2.1% by mass, sulfur 5.5% by mass, carbon 1.2% by mass, and iron 2.2% by mass. And it was confirmed that 18.7% by mass of oxygen was contained.

Next, as the physical properties of the steel sheet having the black plating film, the water repellency, slidability and blackness of the black plating film were examined in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 1
A zinc-nickel plated steel sheet having a nickel content of 12.5% by mass and a plating adhesion amount of 20 g / m ² was prepared in the same type of steel sheet used in Example 1.

The zinc-nickel plated steel sheet is immersed in a 1N nitrate aqueous solution at 50 ° C. for 10 seconds to form a black plating film on the surface of the zinc-nickel plated steel sheet, then washed with water and dried to perform black plating. A steel sheet having a coating was obtained.

As the physical properties of the steel sheet having the black plating film obtained above, the water repellency, slidability and blackness of the black plating film were examined in the same manner as in Example 1. The results are shown in Table 1.

From the results shown in Table 1, the steel sheet having the black plating film obtained in each example is superior in blackness and water repellency to the conventional black plating film, and is also excellent in slidability. You can see that.

1 Base material 2 Nickel plating film 3 Black plating film forming film 4 Black plating film

Claims (7)

A black plating film containing nickel, which further contains phosphorus and sulfur and also contains fluororesin particles. The black plating film according to claim 1, wherein the L value of the black plating film is 3 or less. A method for producing a black plating film, which comprises at least one carboxylic acid and fluororesin particles selected from the group consisting of a nickel compound, a phosphorus compound, a monocarboxylic acid, a polycarboxylic acid, an oxycarboxylic acid, and salts thereof. After forming a black plating film forming film with a black plating film forming plating solution containing, a plating film blackening treatment containing the black plating film forming film and thiourea, alkylenediamine and aromatic sulfonate. A method for producing a black plating film, which comprises contacting with a liquid to form a black plating film. A black plating film produced by the method for producing a black plating film according to claim 3. A laminated plating film having a black plating film on its surface, wherein the black plating film according to claim 1 or 2 is formed on a nickel plating film containing nickel and phosphorus. A method for producing a laminated plating film having a black plating film on the surface, which is at least one selected from the group consisting of nickel compounds, phosphorus compounds, monocarboxylic acids, polycarboxylic acids, oxycarboxylic acids and salts thereof. A nickel plating film is formed with a plating solution for forming a nickel plating film containing a carboxylic acid, and the formed nickel plating film, a nickel compound, a phosphorus compound, a monocarboxylic acid, a polycarboxylic acid, an oxycarboxylic acid and salts thereof. After contacting a black plating film forming plating solution containing at least one carboxylic acid selected from the group consisting of carboxylic acid and fluororesin particles to form a black plating film forming film on the nickel plating film. , Manufacture of a laminated plating film, which comprises contacting the black plating film forming film with a plating film blackening treatment liquid containing thiourea, alkylenediamine and aromatic sulfonate to form a black plating film. Method. A laminated plating film produced by the method for producing a black plating film according to claim 6.