Non-cyanogen plate silver plating solution

Abstract

The invention discloses a non-cyanide silver-gilt electroplate liquid, which comprises a cylinder opening agent, an extender and a potassium hydroxide solution. The cylinder opening agent comprises following raw materials by weight: 1 to 5 percent of silver nitrate, 2 to 10 percent of isonicotinic acid, 5 to 20 percent of tri-imidogen di-phosphate ammonium, 2 to 12 percent of potassium acetate and residual quantity of pure water; the extender comprises following raw materials by weight: 0.1 to 5 percent of a compound of propanetriol and epoxy ethane, 0.01 to 9 percent of ammonium polyethylene with low polymerization degree, 10 to 20 percent of potassium acetate, 20 to 40 percent of isonicotinic acid and residual quantity of pure water; consequently, the electroplate liquid produced does not contain harmful substances such as cyanide and heavy metal, etc., and has low cost and good use effect.

Description

technical field [0001] The invention relates to an electroplating solution, in particular to a cyanide-free silver plating electroplating solution. Background technique [0002] The standard potential of silver is +0.799v. For commonly used metal parts, the silver coating is a cathodic coating. Silver has a unique silver-white luster, is chemically stable to organic acids and alkalis, and its price is cheaper than other precious metals, so it is widely used as a decorative coating in the fields of tableware, jewelry, artwork, etc. Excellent electrical conductivity and brazing performance, it is also widely used in electrical contact materials in the electrical and electronic industries; in addition, silver coatings are also used in lubricating coatings and other special-purpose coatings such as lampshades, reflectors, chemical utensils, etc. [0003] The cyanide silver plating process is still adopted by most of the electroplating silver craftsmen at home and abroad because...

AI Technical Summary

Problems solved by technology

[0005] (1). The overall performance of the coating does not meet the commercial requirements, such as insufficient brightness of the coating, poor bonding with the substrate, or inclusion of organic matter in the coating, resulting in low purity and decreased electrical conductivity, etc.;

[0006] (2). The stability of the plating solution is poor. Many cyanide-free silver plating solutions have problems with the stability of the plating solution to varying degrees, that is, they are sensitive to other metal impurities, resulting in short plating cycles, inconvenience to management and operation, and increased application costs. ;

[0007] (3). The process performance cannot meet the production needs, the dispersion ability of the plating solution is poor, the cathode current density is low, and the anode is easily passivated;

[0008] (4). The cost of plating solution is high