Primer is the initial layer of coating applied to a bare substrate, such as metal or plastic, before the final topcoat. It serves as a binding layer that helps the paint adhere properly and seals porous surfaces. In automotive and industrial manufacturing, primers also contain anti-corrosive agents to protect the underlying material from rust and chemical degradation.
Heard on the job
Make sure the bare steel gets an even coat of primer before it hits the curing oven, or the topcoat will flake off.
Insider tip
Skipping primer to save cycle time usually results in a high scrap rate due to paint delamination during quality checks.