That's an interesting question. There is probably a paint guru on here that knows. I would like to know as well. The last car we painted was a PB 5 electric blue. Due to where we live, we had an old Martin paint mixer Jeff Sands from Kentland Napa mix the lacquer paint. (Yes this was a long time ago) Jeff was the resident expert in this small community for matching paint colors for all the local body shops. At that time there was a new ultra-high gloss Urethane that was compatible to topcoat the Martin Lacquer paint. It got incredibly hard and took some work to get the orange peel that my inexperience with this new Urethane created in the final coats. It sure was sharp a week or so later when I finally wet sanded flat all of my orange peel. I never did that again!