I’m trying to decide on the best finish for flag I’ve made which is impregnated with water based stain. I can’t quite decide which would be the best choice. I’m trying to avoid any yellowing, so I know urethanes are inherently inferior in that department, but would seem to be the most durable. The flag my be partially outdoors, which made me lean toward the water based spar urethane, but I desperately want to avoid as much of the usually beloved warm glow as possible. Polycrylic tends to appear slightly “plasticy” in my opinion, but I’m not sure about water poly.
Which one would yellow the least, while offering the most protection? Am I missing any options?