I worked for a major chemical company that also made paint and knew that their paint that made the most money and on which they spent the most on research was house paint. Houses are out in the weather all year-no winter cover or inside storage. Their owners expect to repaint them infrequently, such as every ten years or so. They also expect a good paint job will require little preparation before repainting. Back then the only house paints were oil paints, so my yacht was painted with top quality oil-based house paint.
All paints consist of binders or resins, pigments, solvents, and additives.
The binder forms the film that sticks to the boat and holds the pigment there. The pigments color the paint, make it opaque and have a good deal to do with UV resistance. Solvents keep the binder dispersed or dissolved and the pigments dispersed in an easy to apply state. They allow the paint to be applied in the correct thickness and then evaporate from the paint film as it dries. Mineral spirits, a petroleum distillate fraction, is the most common solvent in oil-based paints.