Q: I read some non-technical articles mentioning powder coating on wood. How can this be done? Is it because wood is a non-magnetic material?
A: We use electrostatics and not magnetism to deposit the dry powder onto a substrate, but this is still a good question. Most wood has the surface characteristics that allow electrostatic deposition of powder onto the wood. In some cases, like MDF (medium-density fiberboard), the “wood” has to be preheated to allow moisture to migrate to the surface. This migration provides enough conductivity to deposit the charged powder.
One of the challenges to coat wood is having a powder coating chemistry that cures at low temperatures. If the cure temperature is too high, the wood emits volatiles that ruin the coating appearance. The powder coating industry has developed chemistries and processes that allow MDF to be coated commercially.