Conformal coatings like Parylene protect a variety of components, including LEDs, sensors, and circuit card assemblies. If a board component needs to be replaced, however, how easily can the Parylene be removed?
Parylene is a thin, optically clear coating, applied in a vacuum chamber at room temperature. The polymer provides moisture barriers, thermal and UV stability, and dry-film lubricity.
In a webinar titled The Use of Parylene as an Advanced Conformal Coating, a Tech Briefs attendee asked Dick Molin from the Indianapolis, IN-based Specialty Coating Systems:
"What is the repair process of the coating if a board component needs to be replaced?"
Dick Molin, Senior Medical Market Specialist, Specialty Coating Systems: Parylene is very difficult to remove, from a chemistry standpoint. It's almost always necessary to remove it in a physical manner. Sometimes that's through the process of micro-abrasion. Sometimes it’s necessary to surgically remove the Parylene with a scalpel, if you will, from specific areas. If, for instance, the component is on a surface-mounted device that needs to be replaced, it may be necessary, after the replacement of the component, to then do a touch-up with an approved liquid coating in that isolated area, or to perhaps recoat the entire board with Parylene after that.
Have you used Parylene? Share your thoughts below.
Watch the full presentation: The Use of Parylene as an Advanced Conformal Coating.