The carbon fiber sails were pushing 8 grand each and expected to only last up to 5 years. Strong and light weight, but degrade quickly…don’t leave them out in the sun.
"It is naturally black in color and is essentially unaffected by UV exposure."
Doyle Sailmakers: Fiber Guide
Carbon is great in the sun. No worries. What it doesn't like is bending. Carbon is brittle. It's all a trade off.