Animation cels are more fragile than they look. The acetate base can warp and grow brittle, and the hand-applied paint can crack, lift, or stick to whatever it touches. A few habits go a long way toward keeping a cel stable for decades.
Understand the enemies
- Heat and humidity accelerate the breakdown of acetate and can cause paint to soften or adhere to adjacent surfaces.
- Light, especially ultraviolet, fades pigments over time.
- Pressure and direct contact can transfer paint from the cel onto a facing surface (a problem known as ferrotyping or paint transfer).
Storage
- Store cels flat, separated from other cels and from their backgrounds by an acid-free, non-stick interleaving sheet (glassine or a suitable archival tissue).
- Keep them in a cool, stable, dry environment away from radiators, attics, and exterior walls. Avoid swings in temperature and humidity.
- Use acid-free folders or boxes and avoid ordinary PVC sleeves, which can off-gas and damage the cel.
Handling
- Handle by the edges, ideally with clean hands or gloves; skin oils mark both paint and acetate.
- Never flex or roll a cel.
- Keep food, drink, and pens well away from the work surface.
Display
- Frame with UV-filtering glazing and acid-free matting, and never let the glazing press directly against the paint.
- Hang out of direct sunlight and away from heat sources.
- For valuable pieces, consider displaying a high-quality reproduction and keeping the original in proper storage.
When in doubt, do less. Avoid attempting to clean or "repair" paint yourself — consult a conservator experienced with animation art before any intervention.