Dowa Metaltech Co., Ltd.

Yutaro Hirai

Kentaro Arai

Yosuke Sato

Shunsuke Ashidate

A silver-plated product having a higher hardness and more excellent wear resistance than those of conventional silver-plated products, and a method for producing the same. In a method for producing a silver-plated product by forming a surface layer of silver on a base material by electroplating at a current density in a silver-plating solution which is an aqueous solution containing silver potassium cyanide or silver cyanide, potassium cyanide or sodium cyanide, and a benzimidazole (such as 2-mercaptobenzmimidazole or 2-mercaptobenzimidazole sulfonic acid sodium salt dihydrate), the ratios of the concentrations of silver potassium cyanide or silver cyanide, potassium cyanide or sodium cyanide, and the imidazole to the current density during the silver-plating (or the ratios of the concentrations of silver potassium cyanide or silver cyanide and the imidazole to the current density during the silver plating, and the concentration of potassium cyanide or sodium cyanide) are set to be predetermined ranges, respectively.

Silver-plated product and method for producing same

There are provided a silver-plated product having a more excellent wear resistance than that of conventional silver-plated products, and a method for producing the same. The method comprises the steps of: preparing a silver-plating solution which is an aqueous solution containing silver potassium cyanide or silver cyanide, potassium cyanide or sodium cyanide, and a benzothiazole or a derivative thereof; and forming a surface layer of silver on a base material by electroplating at a liquid temperature and at a current density in the silver-plating solution so as to satisfy (BC/A)/D≥10 (° C.·dm/A) assuming that a concentration of free cyanide in the silver-plating solution is A (g/L), that a concentration of a benzothiazole content of the benzothiazole or derivative thereof in the silver-plating solution is B (g/L), that the liquid temperature of the silver-plating solution is C (° C.) and that the current density during the electroplating is D (A/dm).

A silver-plated product which has more excellent minute sliding abrasion resistance property than that of conventional silver-plated products, and a method for producing the same. The silver-plated product is produced by electroplating a base materialof copper or a copper alloy to form an underlying plating layerof nickel or a nickel alloy, a first silver-plating layer of silver (lower silver-plating layer), a zinc-plating layerof zinc serving as an intermediate plating layer, and a second silver-plating layer of silver (upper silver-plating layer)serving as a surface layer, in this order from the base material

There is provided an inexpensive plated product, which can prevent the increase of the contact resistance of a silver-plating film and the change of the color of the surface thereof after reflow-treating a plated product wherein the silver-plating film is formed on a portion of the surface thereof and wherein a tin-plating film is formed on a portion of the other portion of the surface thereof, and a method for producing the same. The plated product is produced by a method including the steps of: forming a nickel-plating filmon a surface of a base materialof copper or a copper alloy; forming a silver-plating filmon a portion of a surface of the nickel-plating film, and forming a tin-plating filmon a portion of the other portion of the surface of the nickel-plating film, to prepare a plated product which has the silver-plating filmand the tin-plating filmon the surface of the nickel-plating filmformed on the base material; and irradiating the surface of the plated product with infrared rays to heat the surface thereof to reflow-treat the tin-plating filmto cause the tin-plating filmto be a reflowed tin-plating layer

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Tokyo, Japan

Yutaro Hirai