What is chemical etching?

Chemical etching is a method of engraving that uses a high-pressure temperature-regulated chemical spray to remove material to create a permanently etched image or shape in metal. A mask or resist is applied to the surface of the material and is selectively removed, exposing the metal, to create the desired image. The material is then placed in an etching machine, typically a conveyor-ised machine consisting of an etch chamber and a rinse chamber.

An etching machine harnesses the corrosive reaction between the chemical and the material and amplifies the effect by heating the solution and spraying at high pressure. The chemical spray dissolves the unprotected metal areas to etch the material. The depth of the etch is controlled by conveyor speed. A slower pass results in a deeper etch whereas a faster pass produces a shallower etch. After etching, the resist layer is removed. 

-Liam Dullaghan Jr., Masteretch Services