Oil paints don’t dry in the way you’re used to with things like watercolor. There isn’t a liquid part of it that is evaporating into the air. Oils dry through a chemical process when exposed to oxygen. [1]https://www.easy-oil-painting-techniques.org/why-does-it-take-so-long-for-oil-paint-to-dry-on-canvas-days.html
Depending on several factors like the type of oil paint you use, oil paints can dry as little as 24 hours or as long as 12 days.[2]https://www.leannerathart.com/blog/oilpaintingmediums-dryingtimes
What can you do to speed up oil paint to dry on canvas? [3]https://www.wikihow.com/Dry-Oil-Paint-Fast
- Minimize the number of layers you use.
- When you are ready, keep your oil paint close (but not to close) to the radiator as warm dry air is the best.
- Use a dehumidifier if you live in a humid climate.