Acid etching also called chemical etching, photo etching is a process of milling sheet metal using corrosive chemicals to selectively etch in specified areas. Several manufacturing steps make up the etching process, each requiring precise controls to produce a quality product.
Acid Metal Etching
Chemical etching on metal creates intricate and fine shapes by dissolving it with a chemical solution. At Sac Marquage, we can process from one piece to mass production and provide very small, thin, or complex parts with high processing accuracy.
Example of metals: marking and chemical engraving on stainless steel, aluminum, brass, copper, steel, etc.
The Engraving Process
The process can be broken down into the following key steps:
- A sheet of metal undergoes chemical cleaning to ensure that it is free of potential contaminants
- The foil is coated with a “photoresist” resistant film
- The pattern to be etched is superimposed on the photosensitive resin-coated sheet, which is then exposed to UV light. The area that is not covered by the etched pattern is activated by the UV light, and this will prevent the acid etching of the material in this area.
- The foil undergoes a development step where the unexposed “photoresist” is removed, leaving uncovered areas that will be etched by the acid
- The developed material goes through the etching process where it is sprayed with the chemical etching agent to etch the required pattern into the metal
- The material is cleaned to remove the remaining “photoresist”
It offers several advantages over mechanical machining, including:
- No thermal stress is introduced into the material
- There is no deburring of the material
- The mechanical properties of the material are unchanged
- The complexity of the pattern to be engraved does not affect the production cost
Sac Marquage uses a range of equipment dedicated to storage, cleaning, chemical etching, and printing on metal.