Electroless deposition (ED) or electroless plating is a chemical process by which metals and metal alloys are deposited onto a surface. Electroless deposition uses a chemical reaction that causes a metal to precipitate and coat nearby surfaces. It is dubbed "electroless" because prior processes use an electric current which is referred to as electroplating. Electroless deposition thus can occur on non-conducting surfaces, making it possible to coat diverse materials including plastics, ceramics, and glass, etc. ED produced films can decorative, anti-corrosive, and conductive. Common applications of ED include films and mirrors containing nickel and/or silver.
Electroless deposition changes the mechanical, magnetic, internal stress, conductivity, and brightening of the substrate. The first industrial application of electroless deposition by the Leonhardt Plating Company has flourished into metallization of plastics, textiles, prevention of corrosion, and jewelry. The microelectronics industry uses ED in the manufacturing of circuit boards, semi-conductive devices, batteries, and sensors.