Chemical etching is a method of engraving that uses a high-pressure high-temperature chemical spray to remove material and create a permanent etched image in metal¹. Here's how the process works:
1. **Lamination**: The material is cleaned to remove all surface contamination, then laminated with a UV sensitive photoresist film¹.
2. **Exposure**: A photo tool containing the desired artwork is placed on top of the laminated material and exposed to UV light. The UV light hardens the laminated film through the clear areas of the photo tool¹.
3. **Developing**: The resist film on non-UV exposed areas is chemically developed to reveal the desired image. Before etching, the resist coated area is heated to improve acid resistance¹.
4. **Etching**: The material is placed in the etching machine where it is sprayed with a high-pressure temperature regulated chemical spray (most commonly Ferric Chloride). The solution etches away the unprotected portions of the material to reproduce the desired image¹.
5. **Stripping**: The resist is then stripped, either manually or in a stripping machine, ready for any post-etch processes required¹.
This process, sometimes referred to as photochemical etching, is capable of reproducing an exceptional level of detail¹. It's a versatile manufacturing technique that retains hardness, temper, magnetic permeability, and other qualities without causing excessive stress on the material¹. Tooling costs are very low and design changes can easily be incorporated¹. It's an accurate and economical solution for many precision metal applications¹.
Source:
(1) Chemical Etching Process | What is Chemical Etching?.
https://www.masteretching.com/chemical-etching-process.
(2) What is Chemical Etching & How Does It Work? Precision Micro.
https://www.precisionmicro.com/chemical-etching/chemical-etching-process/.
(3) Chemical milling - Wikipedia.
https://en.wikipedia.org/wiki/Chemical_milling.
