Below is a list of Coating Services manufacturers from California. Coating services refer to various processes that are used to apply a thin layer of material onto another material, which is often referred to as the substrate. There are many different purposes that coatings can serve, but the primary two reasons to coat a substrate are to protect the substrate from environmental conditions, corrosion and wear-and-tear. Coating can also give any desired aesthetic characteristics such as color, tint, scent and texture to the substrate that it does not already possess.