Electroless plating bath for forming a nickel alloy coating having a high phosphorus content

摘要

An electroless plating bath for forming a nickel-phosphorus alloy coating having a high phosphorus content contains in water nickel ions, hypophosphite as a reducing agent for nickel ions, a pH adjustor, a pH buffering agent, a small amount of a stress reducing agent and tri(alkali metal) N-(2-hydroxyethyl)ethylenediamine-N, N', N'-triacetate as a first phosphorus deposition promotor. It may further contain at least one sulfate selected from ammonium sulfate, lithium sulfate, potassium sulfate and sodium sulfate as a second phosphorus deposition promotor.